Introduction

This page is a complete reference of Java Flight Recorder (JFR) events for OpenJDK 27 (jdk-27+35, permalink, 20-September-2026). JFR events are the foundation of JVM profiling and observability — they capture runtime data such as garbage collection pauses, CPU load, thread activity, class loading, compilations, and more. The events listed here are collected from the JFR event configuration and the OpenJDK source code. Visit the jfreventcollector repository for more information. This is also where you can contribute additional event descriptions, if you don't want to contribute them directly to the OpenJDK. The site generator lives on GitHub, too.

For each JFR event you'll find its fields, default configuration profiles (continuous / profiling), real-world examples from the Renaissance benchmark, and — where available — source code context to help you understand what each event means during JVM performance analysis.

This page is maintained by Johannes Bechberger of the SapMachine team at SAP and contributors.

Some events have fake end times/durations; these are hidden in the event description here.

Flight Recorder

DumpReason

default profiling startTime 11 17 21 25 27 28

Category: Flight Recorder

Who requested the recording and why

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/recorder/repository/jfrEmergencyDump.cpp:

    if (_jt != nullptr) {
      assert(_jt->thread_state() == _thread_in_vm, "invariant");
      _jt->set_thread_state(_thread_in_native);
    }
  }
};

static void post_events(bool exception_handler, bool oom, Thread * thread) {
  if (exception_handler) {
    EventShutdown e;
    e.set_reason(oom ? "CrashOnOutOfMemoryError" : "VM Error");
    e.commit();
  }
  EventDumpReason event;
  event.set_reason(exception_handler && oom ? "CrashOnOutOfMemoryError" : exception_handler ? "Crash" : "Out of Memory");
  event.set_recordingId(-1);
  event.commit();
}

static volatile traceid _jfr_shutdown_tid = 0;

static bool guard_reentrancy() {
  const traceid shutdown_tid = AtomicAccess::load(&_jfr_shutdown_tid);
  if (shutdown_tid == max_julong) {
    // Someone tried but did not have a proper thread for the purpose.

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
reason string Reason Reason for writing recording data to disk
recordingId int Recording Id Id of the recording that triggered the dump, or -1 if it was not related to a recording

DataLoss

default profiling startTime 11 17 21 25 27 28

Category: Flight Recorder

Data could not be copied out from a buffer, typically because of contention

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/recorder/storage/jfrStorage.cpp:

      assert(!buffer->transient(), "invariant");
      assert(buffer->lease(), "invariant");
      storage_instance.control().increment_leased();
      return buffer;
    }
  }
  return acquire_transient(size, thread);
}

static void write_data_loss_event(JfrBuffer* buffer, u8 unflushed_size, Thread* thread) {
  assert(buffer != nullptr, "invariant");
  assert(buffer->empty(), "invariant");
  const u8 total_data_loss = thread->jfr_thread_local()->add_data_lost(unflushed_size);
  if (EventDataLoss::is_enabled()) {
    JfrNativeEventWriter writer(buffer, thread);
    writer.begin_event_write(false);
    writer.write<u8>(EventDataLoss::eventId);
    writer.write(JfrTicks::now());
    writer.write(unflushed_size);
    writer.write(total_data_loss);
    writer.end_event_write(false);
  }
}

static void write_data_loss(BufferPtr buffer, Thread* thread) {
  assert(buffer != nullptr, "invariant");
  const size_t unflushed_size = buffer->unflushed_size();
  buffer->reinitialize();

src/hotspot/share/jfr/jni/jfrJniMethod.cpp:

JVM_ENTRY_NO_ENV(jlong, jfr_host_memory_usage(JNIEnv* env, jclass jvm))
  physical_memory_size_type memory_usage = 0;
  if (!os::Machine::used_memory(memory_usage)) {
    // Return -1 to signal failure to get memory usage.
    return static_cast<jlong>(-1);
  }
  return static_cast<jlong>(memory_usage);
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_emit_data_loss(JNIEnv* env, jclass jvm, jlong bytes))
  EventDataLoss::commit(bytes, min_jlong);
JVM_END

JVM_ENTRY_NO_ENV(jlong, jfr_register_stack_filter(JNIEnv* env,  jclass jvm, jobjectArray classes, jobjectArray methods))
  return JfrStackFilterRegistry::add(classes, methods, thread);
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_unregister_stack_filter(JNIEnv* env,  jclass jvm, jlong id))
  JfrStackFilterRegistry::remove(id);
JVM_END

NO_TRANSITION(jlong, jfr_nanos_now(JNIEnv* env, jclass jvm))

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
amount ulong: bytes Amount Amount lost data
total ulong: bytes Total Total lost amount for thread

Flush

experimental startTime duration 14 17 21 25 27 28

Category: Flight Recorder

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/recorder/service/jfrRecorderService.cpp:

template <typename Functor>
static u4 invoke(Functor& f) {
  f.process();
  return f.elements();
}

template <typename Functor>
static u4 invoke_with_flush_event(Functor& f) {
  const u4 elements = invoke(f);
  EventFlush e(UNTIMED);
  e.set_starttime(f.start_time());
  e.set_endtime(f.end_time());
  e.set_flushId(flushpoint_id);
  e.set_elements(f.elements());
  e.set_size(f.size());
  e.commit();
  return elements;
}

class StackTraceRepository : public StackObj {
 private:

Event configuration settings across JFR profiles
Configuration enabled threshold
default false 0 ns
profiling false 0 ns

Event fields with their types and descriptions
Field Type Description
flushId ulong Flush Identifier
elements ulong Elements Written
size ulong: bytes Size Written

Examples 3
Example event data values and properties
elements ulong
62
flushId ulong
22
size ulong: bytes
358890
startTime long: millis
22876915390
Example event data values and properties
elements ulong
4547
flushId ulong
201
size ulong: bytes
958879
startTime long: millis
458023471736
Example event data values and properties
elements ulong
1260
flushId ulong
331
size ulong: bytes
321668
startTime long: millis
489853249572

ActiveSetting

default profiling startTime duration stackTrace 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/ActiveSettingEvent.java

Category: Flight Recorder

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

public final class JDKEvents {

    private static final Class<?>[] eventClasses = {
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        // jdk.internal.event.* classes need their mirror
        // event class to be listed in the MirrorEvents class.
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ErrorThrownEvent.class,
        jdk.internal.event.ExceptionStatisticsEvent.class,
        jdk.internal.event.ExceptionThrownEvent.class,
        jdk.internal.event.FileForceEvent.class,
        jdk.internal.event.FileReadEvent.class,
        jdk.internal.event.FileWriteEvent.class,
        jdk.internal.event.ProcessStartEvent.class,

src/jdk.jfr/share/classes/jdk/jfr/internal/PlatformRecorder.java:

                        r.getId(),
                        r.getName(),
                        path == null ? null : path.getRealPathText(),
                        r.isToDisk(),
                        age == null ? Long.MAX_VALUE : age.toMillis(),
                        flush == null ? Long.MAX_VALUE : flush.toMillis(),
                        size == null ? Long.MAX_VALUE : size,
                        rStart == null ? Long.MAX_VALUE : rStart.toEpochMilli(),
                        rDuration == null ? Long.MAX_VALUE : rDuration.toMillis()
                    );
                }
            }
        }
        if (ActiveSettingEvent.enabled()) {
            for (EventControl ec : MetadataRepository.getInstance().getEventControls()) {
                ec.writeActiveSettingEvent(timestamp);
            }
        }
    }

    private void periodicTask() {
        if (!JVMSupport.hasJFR()) {
            return;
        }
        while (true) {

src/jdk.jfr/share/classes/jdk/jfr/internal/EventControl.java:

    void writeActiveSettingEvent(long timestamp) {
        if (!type.isRegistered()) {
            return;
        }
        for (NamedControl nc : namedControls) {
            if (nc.control.isVisible(type.hasEventHook()) && type.isVisible()) {
                String value = nc.control.getLastValue();
                if (value == null) {
                    value = nc.control.getDefaultValue();
                }
                if (ActiveSettingEvent.enabled()) {
                    ActiveSettingEvent.commit(timestamp, type.getId(), nc.name(), value);
                }
            }
        }
    }

    public ArrayList<NamedControl> getNamedControls() {
        return namedControls;
    }

    public PlatformEventType getEventType() {
        return type;

src/jdk.jfr/share/classes/jdk/jfr/events/ActiveSettingEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.RemoveFields;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "ActiveSetting")
@Label("Recording Setting")
@Category("Flight Recorder")
@RemoveFields({"duration", "eventThread", "stackTrace"})
public final class ActiveSettingEvent extends AbstractJDKEvent {

    // The order of these fields must be the same as the parameters in
    // commit(... , long, String, String)

    @Label("Event Id")
    public long id;

    @Label("Setting Name")
    public String name;

    @Label("Setting Value")

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
id long Event Id
name string Setting Name
value string Setting Value

Examples 3
Example event data values and properties
id long
11
name string
threshold
startTime long: millis
447752338153
value string
0 ms
Example event data values and properties
id long
18
name string
enabled
startTime long: millis
361737433
value string
true
Example event data values and properties
id long
1899
name string
enabled
startTime long: millis
453048059860
value string
true

ActiveRecording

default profiling startTime duration stackTrace 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/ActiveRecordingEvent.java

Category: Flight Recorder

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

public final class JDKEvents {

    private static final Class<?>[] eventClasses = {
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        // jdk.internal.event.* classes need their mirror
        // event class to be listed in the MirrorEvents class.
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ErrorThrownEvent.class,
        jdk.internal.event.ExceptionStatisticsEvent.class,
        jdk.internal.event.ExceptionThrownEvent.class,
        jdk.internal.event.FileForceEvent.class,
        jdk.internal.event.FileReadEvent.class,
        jdk.internal.event.FileWriteEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,

src/jdk.jfr/share/classes/jdk/jfr/internal/PlatformRecorder.java:

                // and check for missing files. This will emit more error logs that can be seen in subsequent recordings.
                for (PlatformRecording r : getRecordings()) {
                    r.removeNonExistantPaths();
                }
            }
        }
        // Decrease initial reference count
        chunk.release();
        FilePurger.purge();
    }

    private void writeMetaEvents() {
        long timestamp = JVM.counterTime();
        if (ActiveRecordingEvent.enabled()) {
            for (PlatformRecording r : getRecordings()) {
                if (r.getState() == RecordingState.RUNNING && r.shouldWriteMetadataEvent()) {
                    WriteablePath path = r.getDestination();
                    Duration age = r.getMaxAge();
                    Duration flush = r.getFlushInterval();
                    Long size = r.getMaxSize();
                    Instant rStart = r.getStartTime();
                    Duration rDuration = r.getDuration();
                    ActiveRecordingEvent.commit(
                        timestamp,
                        r.getId(),
                        r.getName(),
                        path == null ? null : path.getRealPathText(),
                        r.isToDisk(),
                        age == null ? Long.MAX_VALUE : age.toMillis(),
                        flush == null ? Long.MAX_VALUE : flush.toMillis(),
                        size == null ? Long.MAX_VALUE : size,
                        rStart == null ? Long.MAX_VALUE : rStart.toEpochMilli(),
                        rDuration == null ? Long.MAX_VALUE : rDuration.toMillis()
                    );

src/jdk.jfr/share/classes/jdk/jfr/events/ActiveRecordingEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "ActiveRecording")
@Label("Flight Recording")
@Category("Flight Recorder")
@RemoveFields({"duration", "eventThread", "stackTrace"})
public final class ActiveRecordingEvent extends AbstractJDKEvent {

    // The order of these fields must be the same as the parameters in
    // commit(... , long, String, String, long, long, long, long, long)

    @Label("Id")
    public long id;

    @Label("Name")
    public String name;

    @Label("Destination")

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
id long Id
name string Name
destination string Destination
disk boolean 21+ To Disk
maxAge long: millis Max Age
flushInterval long: millis 14+ Flush Interval
maxSize long: bytes Max Size
recordingStart long: epochmillis Start Time
recordingDuration long: millis Recording Duration

Examples 3
Example event data values and properties
destination string
/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseG1GC_events.jfr
disk boolean
true
flushInterval long: millis
1000
id long
1
maxAge long: millis
9223372036854775807
maxSize long: bytes
0
name string
1
recordingDuration long: millis
27000
recordingStart long: epochmillis
1788871963460
startTime long: millis
7977570347
Example event data values and properties
destination string
/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseParallelGC.jfr
disk boolean
true
flushInterval long: millis
1000
id long
1
maxAge long: millis
9223372036854775807
maxSize long: bytes
262144000
name string
1
recordingDuration long: millis
9223372036854775807
recordingStart long: epochmillis
1789259151646
startTime long: millis
449443387277
Example event data values and properties
destination string
/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseG1GC.jfr
disk boolean
true
flushInterval long: millis
1000
id long
1
maxAge long: millis
9223372036854775807
maxSize long: bytes
262144000
name string
1
recordingDuration long: millis
9223372036854775807
recordingStart long: epochmillis
1788871449508
startTime long: millis
501868472749

JVM

JVMInformation

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Java Virtual Machine

Description of JVM and the Java application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrRedactedEvents.cpp:

    event.commit();
  }
}

void JfrRedactedEvents::log_jvm_information_redaction(const char* type, const String* redacted) {
  const char* text = String::c_str(redacted);
  if (text != nullptr && strstr(text, REDACTED) != nullptr) {
    log_debug(jfr, redact)("Redacted %s '%s'", type, text);
  }
}

void JfrRedactedEvents::emit_jvm_information(bool log) {
  ensure_initialized();
  EventJVMInformation event;
  event.set_jvmName(VM_Version::vm_name());
  event.set_jvmVersion(VM_Version::internal_vm_info_string());
  event.set_javaArguments(String::c_str(_redacted_java_command_line));
  event.set_jvmArguments(String::c_str(_redacted_jvm_command_line));
  event.set_jvmFlags(String::c_str(_redacted_flags_command_line));
  event.set_jvmStartTime(Management::vm_init_done_time());
  event.set_pid(os::current_process_id());
  event.commit();
  if (log) {
    log_jvm_information_redaction("Java Arguments", _redacted_java_command_line);
    log_jvm_information_redaction("JVM Arguments", _redacted_jvm_command_line);

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
jvmName string JVM Name
jvmVersion string JVM Version
jvmArguments string JVM Command Line Arguments
jvmFlags string JVM Settings File Arguments
javaArguments string Java Application Arguments
jvmStartTime long: epochmillis JVM Start Time
pid long Process Identifier

Examples 3
Example event data values and properties
javaArguments string
/home/runner/work/jfrevents/jfrevents/.cache/renaissance.jar -t 5 -r 1 all
jvmArguments string
-XX:StartFlightRecording=filename=/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseG1GC.jfr,settings=/home/runner/work/jfrevents/jfrevents/.cache/jfc.jfc -XX:+UseG1GC
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1788871449128
jvmVersion string
OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS) for linux-amd64 JRE (25.0.4.1+1-LTS), built on 2026-08-14T07:36:00Z with gcc 14.2.0
pid long
2534
startTime long: millis
501870624384
Example event data values and properties
javaArguments string
/home/runner/work/jfrevents/jfrevents/.cache/renaissance.jar -t 5 -r 1 all
jvmArguments string
-XX:StartFlightRecording=filename=/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseParallelGC.jfr,settings=/home/runner/work/jfrevents/jfrevents/.cache/jfc.jfc -XX:+UseParallelGC
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1789259151398
jvmVersion string
OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS) for linux-amd64 JRE (25.0.4.1+1-LTS), built on 2026-08-14T07:36:00Z with gcc 14.2.0
pid long
2150
startTime long: millis
470826269406
Example event data values and properties
javaArguments string
/home/runner/work/jfrevents/jfrevents/.cache/jfr_sample_app.jar
jvmArguments string
--add-exports=java.base/jdk.internal.vm.annotation=ALL-UNNAMED -Djdk.attach.allowAttachSelf=true -XX:+UnlockDiagnosticVMOptions -XX:DiagnoseSyncOnValueBasedClasses=2 -XX:NativeMemoryTracking=summary -XX:StartFlightRecording=filename=/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseG1GC_even…
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1788871963118
jvmVersion string
OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS) for linux-amd64 JRE (25.0.4.1+1-LTS), built on 2026-08-14T07:36:00Z with gcc 14.2.0
pid long
5013
startTime long: millis
23227602207

InitialSystemProperty

default profiling startTime end of every chunk 11 17 21 25 27 28

Category: Java Virtual Machine

System Property at JVM start

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrRedactedEvents.cpp:

           value = REDACTED;
        }
        if (log && value != nullptr && strstr(value, REDACTED) != nullptr) {
          log_debug(jfr, redact)("Redacted initial system property named '%s'", p->key());
        }
        _initial_system_properties->append(new StringKeyValue(p->key(), value));
      }
    }
  }

  JfrTicks time_stamp = JfrTicks::now();
  for (int i = 0; i < _initial_system_properties->length(); i++) {
    StringKeyValue* pair = _initial_system_properties->at(i);
    EventInitialSystemProperty event(UNTIMED);
    event.set_key(pair->key());
    event.set_value(pair->value());
    event.set_starttime(time_stamp);
    event.set_endtime(time_stamp);
    event.commit();
  }
}

bool JfrRedactedEvents::match_flag(const char* flag_name, const char* arg) {
  if (flag_name == nullptr || arg == nullptr) {
    return false;

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
key string Key
value string Value

Examples 3
Example event data values and properties
key string
jdk.attach.allowAttachSelf
startTime long: millis
364515232
value string
true
Example event data values and properties
key string
java.vm.vendor
startTime long: millis
451440069110
value string
SAP SE
Example event data values and properties
key string
java.vm.specification.name
startTime long: millis
462141525582
value string
Java Virtual Machine Specification

JVM: Class Loading

ClassLoad

startTime duration eventThread stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / Class Loading

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/classfile/systemDictionary.hpp:

//         readers (we must ensure write ordering)
//
// Note that placeholders are deleted at any time, as they are removed
// when a class is completely loaded. Therefore, readers as well as writers
// of placeholders must hold the SystemDictionary_lock.
//

class BootstrapInfo;
class ClassFileStream;
class ClassLoadInfo;
class Dictionary;
class PackageEntry;
class GCTimer;
class EventClassLoad;
class Symbol;

template <class E> class GrowableArray;

class SystemDictionary : AllStatic {
  friend class AOTLinkedClassBulkLoader;
  friend class BootstrapInfo;
  friend class LambdaProxyClassDictionary;
  friend class vmClasses;

 public:

src/hotspot/share/classfile/systemDictionary.hpp:

  static bool add_loader_constraint(Symbol* name, Klass* klass_being_linked,  Handle loader1,
                                    Handle loader2);
  static InstanceKlass* load_shared_class(InstanceKlass* ik,
                                          Handle class_loader,
                                          Handle protection_domain,
                                          const ClassFileStream *cfs,
                                          PackageEntry* pkg_entry,
                                          TRAPS);
  static void preload_class(Handle class_loader, InstanceKlass* ik, TRAPS);
  static Handle get_loader_lock_or_null(Handle class_loader);
  static InstanceKlass* find_or_define_instance_class(Symbol* class_name,
                                                      Handle class_loader,
                                                      InstanceKlass* k, TRAPS);
  JFR_ONLY(static void post_class_load_event(EventClassLoad* event,
                                             const InstanceKlass* k,
                                             const ClassLoaderData* init_cld);)

public:
  static bool is_system_class_loader(oop class_loader);
  static bool is_platform_class_loader(oop class_loader);
  static bool is_boot_class_loader(oop class_loader) { return class_loader == nullptr; }
  static bool is_builtin_class_loader(oop class_loader) {
    return is_boot_class_loader(class_loader)      ||
           is_platform_class_loader(class_loader)  ||
           is_system_class_loader(class_loader);

src/hotspot/share/classfile/systemDictionary.cpp:

// SystemDictionary::resolve_instance_class_or_null is the main function for class name resolution.
// After checking if the InstanceKlass already exists, it checks for ClassCircularityError and
// whether the thread must wait for loading in parallel.  It eventually calls load_instance_class,
// which will load the class via the bootstrap loader or call ClassLoader.loadClass().
// This can return null, an exception or an InstanceKlass.
InstanceKlass* SystemDictionary::resolve_instance_class_or_null(Symbol* name,
                                                                Handle class_loader,
                                                                TRAPS) {
  // name must be in the form of "java/lang/Object" -- cannot be "Ljava/lang/Object;"
  DEBUG_ONLY(ResourceMark rm(THREAD));
  assert(name != nullptr && !Signature::is_array(name) &&
         !Signature::has_envelope(name), "invalid class name: %s", name == nullptr ? "nullptr" : name->as_C_string());

  EventClassLoad class_load_event;

  HandleMark hm(THREAD);

  ClassLoaderData* loader_data = register_loader(class_loader);
  Dictionary* dictionary = loader_data->dictionary();

  // Do lookup to see if class already exists.
  InstanceKlass* probe = dictionary->find_class(THREAD, name);
  if (probe != nullptr) return probe;

  // Non-bootstrap class loaders will call out to class loader and

src/hotspot/share/classfile/systemDictionary.cpp:

// Note: this method is much like resolve_class_from_stream, but
// does not publish the classes in the SystemDictionary.
// Handles Lookup.defineClass hidden.
InstanceKlass* SystemDictionary::resolve_hidden_class_from_stream(
                                                     ClassFileStream* st,
                                                     Symbol* class_name,
                                                     Handle class_loader,
                                                     const ClassLoadInfo& cl_info,
                                                     TRAPS) {

  EventClassLoad class_load_event;
  ClassLoaderData* loader_data;

  // - for hidden classes that are not strong: create a new CLD that has a class holder and
  //                                           whose loader is the Lookup class's loader.
  // - for hidden class: add the class to the Lookup class's loader's CLD.
  assert (cl_info.is_hidden(), "only used for hidden classes");
  bool create_mirror_cld = !cl_info.is_strong_hidden();
  loader_data = register_loader(class_loader, create_mirror_cld);

  assert(st != nullptr, "invariant");

src/hotspot/share/classfile/systemDictionary.cpp:

  // preload_class() must be called in the correct order -- all super types must have
  // already been loaded.
  if (ik->java_super() != nullptr) {
    assert(ik->java_super()->is_loaded(), "must be");
  }

  Array<InstanceKlass*>* interfaces = ik->local_interfaces();
  int num_interfaces = interfaces->length();
  for (int index = 0; index < num_interfaces; index++) {
    assert(interfaces->at(index)->is_loaded(), "must be");
  }
#endif

  EventClassLoad class_load_event;

  ClassLoaderData* loader_data = ClassLoaderData::class_loader_data(class_loader());
  oop java_mirror = ik->archived_java_mirror();
  precond(java_mirror != nullptr);
  assert(java_lang_Class::module(java_mirror) != nullptr, "must have been archived");

  Handle pd(THREAD, java_lang_Class::protection_domain(java_mirror));
  PackageEntry* pkg_entry = ik->package();
  assert(pkg_entry != nullptr || ClassLoader::package_from_class_name(ik->name()) == nullptr,
         "non-empty packages must have been archived");

src/hotspot/share/classfile/systemDictionary.cpp:

    update_dictionary(THREAD, ik, loader_data);
  }

  if (class_load_event.should_commit()) {
    JFR_ONLY(post_class_load_event(&class_load_event, ik, loader_data);)
  }

  assert(ik->is_loaded(), "Must be in at least loaded state");
}

#endif // INCLUDE_CDS

#if INCLUDE_JFR
void SystemDictionary::post_class_load_event(EventClassLoad* event, const InstanceKlass* k, const ClassLoaderData* init_cld) {
  assert(event != nullptr, "invariant");
  assert(k != nullptr, "invariant");
  event->set_loadedClass(k);
  event->set_definingClassLoader(k->class_loader_data());
  event->set_initiatingClassLoader(init_cld);
  event->commit();
}
#endif // INCLUDE_JFR

InstanceKlass* SystemDictionary::load_instance_class_impl(Symbol* class_name, Handle class_loader, TRAPS) {

src/hotspot/share/classfile/vmClasses.cpp:

  InstanceStackChunkKlass::init_offset_of_stack();
}

#if INCLUDE_CDS

void vmClasses::resolve_shared_class(InstanceKlass* klass, ClassLoaderData* loader_data, Handle domain, TRAPS) {
  assert(!Universe::is_fully_initialized(), "We can make short cuts only during VM initialization");
  assert(klass->in_aot_cache(), "Must be shared class");
  if (klass->class_loader_data() != nullptr) {
    return;
  }

  EventClassLoad class_load_event;

  // add super and interfaces first
  InstanceKlass* super = klass->super();
  if (super != nullptr && super->class_loader_data() == nullptr) {
    assert(super->is_instance_klass(), "Super should be instance klass");
    resolve_shared_class(super, loader_data, domain, CHECK);
  }

  Array<InstanceKlass*>* ifs = klass->local_interfaces();
  for (int i = 0; i < ifs->length(); i++) {
    InstanceKlass* ik = ifs->at(i);

src/hotspot/share/cds/lambdaProxyClassDictionary.cpp:

  assert(shared_nest_host->is_same_class_package(lambda_ik),
         "lambda proxy class and its nest host must be in the same package");
  // The lambda proxy class and its nest host have the same class loader and class loader data,
  // as verified in add_lambda_proxy_class()
  assert(shared_nest_host->class_loader() == class_loader(), "mismatched class loader");
  assert(shared_nest_host->class_loader_data() == ClassLoaderData::class_loader_data(class_loader()), "mismatched class loader data");
  lambda_ik->set_nest_host(shared_nest_host);

  // Ensures the nest host is the same as the lambda proxy's
  // nest host recorded at dump time.
  InstanceKlass* nest_host = caller_ik->nest_host(THREAD);
  assert(nest_host == shared_nest_host, "mismatched nest host");

  EventClassLoad class_load_event;

  // Add to class hierarchy, and do possible deoptimizations.
  lambda_ik->add_to_hierarchy(THREAD);
  // But, do not add to dictionary.

  lambda_ik->link_class(CHECK_NULL);
  // notify jvmti
  if (JvmtiExport::should_post_class_load()) {
    JvmtiExport::post_class_load(THREAD, lambda_ik);
  }
  if (class_load_event.should_commit()) {

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default false true 0 ms
profiling false true 0 ms

Event fields with their types and descriptions
Field Type Description
loadedClass Class Loaded Class
definingClassLoader ClassLoader Defining Class Loader
initiatingClassLoader ClassLoader Initiating Class Loader

Examples 3
Example event data values and properties
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
initiatingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
loadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
true
modifiers int
4112
name string
org.apache.spark.executor.ExecutorMetricsPoller$$Lambda/0x000000008dae9000
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/executor
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/Class;Ljava/lang/String;[BIILjava/security/ProtectionDomain;ZILjava/lang/Object;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
458048087323
Example event data values and properties
definingClassLoader ClassLoader
null
initiatingClassLoader ClassLoader
null
loadedClass Class
classLoader ClassLoader
null
hidden boolean
true
modifiers int
16
name string
java.lang.invoke.LambdaForm$MH/0x0000000082ae1800
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang/invoke
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/Class;Ljava/lang/String;[BIILjava/security/ProtectionDomain;ZILjava/lang/Object;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
450529520094
Example event data values and properties
definingClassLoader ClassLoader
name string
bootstrap
type Class
null
initiatingClassLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
loadedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/jar/JarOutputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/jar
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Z)[Ljava/lang/reflect/Method;
hidden boolean
false
modifiers int
258
name string
getDeclaredMethods0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Class
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
386591859

ClassDefine

startTime eventThread stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / Class Loading

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/support/jfrClassDefineEvent.cpp:

static traceid get_source(const InstanceKlass* ik, JavaThread* jt) {
  traceid source_id = 0;
  if (is_jdk_module(ik, jt)) {
    source_id = module_path(ik, jt);
  } else if (ik->class_loader_data()->is_the_null_class_loader_data()) {
    source_id = caller_path(ik, jt);
  } else {
    source_id = class_loader_path(ik, jt);
  }
  return source_id;
}

static inline void send_event(const InstanceKlass* ik, traceid source_id) {
  EventClassDefine event;
  event.set_definedClass(ik);
  event.set_definingClassLoader(ik->class_loader_data());
  event.set_source(source_id);
  event.commit();
}

void JfrClassDefineEvent::on_creation(const InstanceKlass* ik, const ClassFileParser& parser, JavaThread* jt) {
  assert(ik != nullptr, "invariant");
  assert(ik->trace_id() != 0, "invariant");
  assert(!parser.is_internal(), "invariant");
  assert(jt != nullptr, "invariant");

  if (EventClassDefine::is_enabled() && is_not_retransforming(ik, jt)) {
    ResourceMark rm(jt);
    traceid source_id = 0;
    const ClassFileStream& stream = parser.stream();
    if (stream.source() != nullptr) {
      if (stream.from_boot_loader_modules_image()) {
        assert(is_jdk_module(ik, jt), "invariant");
        source_id = module_path(ik, jt);
      } else {
        source_id = JfrSymbolTable::add(stream.source());
      }
    } else {

src/hotspot/share/jfr/support/jfrClassDefineEvent.cpp:

  const char* file_type = cl->file_type_string();
  assert(file_type != nullptr, "invariant");
  len += strlen(file_type) + 3; // ":/" + null
  char* const url = NEW_RESOURCE_ARRAY_IN_THREAD(jt, char, len);
  jio_snprintf(url, len, "%s%s%s", file_type, ":/", path);
  return JfrSymbolTable::add(url);
}

void JfrClassDefineEvent::on_restoration(const InstanceKlass* ik, JavaThread* jt) {
  assert(ik != nullptr, "invariant");
  assert(ik->trace_id() != 0, "invariant");
  assert(jt != nullptr, "invariant");

  if (EventClassDefine::is_enabled()) {
    ResourceMark rm(jt);
    assert(is_not_retransforming(ik, jt), "invariant");
    const int index = ik->shared_classpath_index();
    assert(index >= 0, "invariant");
    const AOTClassLocation* const cl = AOTClassLocationConfig::runtime()->class_location_at(index);
    assert(cl != nullptr, "invariant");
    send_event(ik, cl->is_modules_image() ? module_path(ik, jt) : get_source(cl, jt));
  }
}
#endif

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default false true
profiling false true

Event fields with their types and descriptions
Field Type Description
definedClass Class Defined Class
definingClassLoader ClassLoader Defining Class Loader
source Symbol 26+ Source

Examples 3
Example event data values and properties
definedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/api/python/PythonWorkerFactory
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/api/python
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/String;[BIILjava/security/ProtectionDomain;Ljava/lang/String;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass1
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
480352434300
Example event data values and properties
definedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
org/apache/spark/scheduler/StopCoordinator$
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/scheduler
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/String;[BIILjava/security/ProtectionDomain;Ljava/lang/String;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass1
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
475253934265
Example event data values and properties
definedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/security/Security
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/security
definingClassLoader ClassLoader
name string
bootstrap
type Class
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
8
lineNumber int
340
method Method
descriptor string
()Ljdk/internal/access/JavaSecurityPropertiesAccess;
hidden boolean
false
modifiers int
9
name string
getJavaSecurityPropertiesAccess
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
jdk/internal/access/SharedSecrets
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/access
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
375729010

ClassRedefinition

default profiling startTime 15 17 21 25 27 28

Category: Java Virtual Machine / Class Loading

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/prims/jvmtiRedefineClasses.cpp:

  _timer_rsc_phase1.stop();
  if (log_is_enabled(Info, redefine, class, timer)) {
    _timer_rsc_phase2.start();
  }

  if (the_class->oop_map_cache() != nullptr) {
    // Flush references to any obsolete methods from the oop map cache
    // so that obsolete methods are not pinned.
    the_class->oop_map_cache()->flush_obsolete_entries();
  }

  increment_class_counter(the_class);

  if (EventClassRedefinition::is_enabled()) {
    EventClassRedefinition event;
    event.set_classModificationCount(java_lang_Class::classRedefinedCount(the_class->java_mirror()));
    event.set_redefinedClass(the_class);
    event.set_redefinitionId(_id);
    event.commit();
  }

  {
    ResourceMark rm(current);
    // increment the classRedefinedCount field in the_class and in any
    // direct and indirect subclasses of the_class
    physical_memory_size_type avail_mem = 0;

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
redefinedClass Class Redefined Class
classModificationCount int Class Modification Count The number of times the class has changed
redefinitionId ulong Class Redefinition Id

Examples 3
Example event data values and properties
classModificationCount int
2
redefinedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/ArrayList
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
redefinitionId ulong
2
startTime long: millis
1008236015
Example event data values and properties
classModificationCount int
2
redefinedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/ArrayList
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
redefinitionId ulong
2
startTime long: millis
1412196725
Example event data values and properties
classModificationCount int
2
redefinedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/ArrayList
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
redefinitionId ulong
2
startTime long: millis
1438881361

RedefineClasses

default profiling startTime duration eventThread stackTrace 15 17 21 25 27 28

Category: Java Virtual Machine / Class Loading

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/prims/jvmtiEnv.cpp:

    event.set_classCount(class_count);
    event.set_redefinitionId(op.id());
    event.commit();
  }
  return error;
} /* end RetransformClasses */


// class_count - pre-checked to be greater than or equal to 0
// class_definitions - pre-checked for null
jvmtiError
JvmtiEnv::RedefineClasses(jint class_count, const jvmtiClassDefinition* class_definitions) {
//TODO: add locking
  EventRedefineClasses event;
  VM_RedefineClasses op(class_count, class_definitions, jvmti_class_load_kind_redefine);
  VMThread::execute(&op);
  jvmtiError error = op.check_error();
  if (error == JVMTI_ERROR_NONE) {
    event.set_classCount(class_count);
    event.set_redefinitionId(op.id());
    event.commit();
  }
  return error;
} /* end RedefineClasses */

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 0 ms
profiling true true 0 ms

Event fields with their types and descriptions
Field Type Description
classCount int Class Count
redefinitionId ulong Class Redefinition Id

Examples 3
Example event data values and properties
classCount int
1
redefinitionId ulong
2
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/instrument/ClassDefinition;)V
hidden boolean
false
modifiers int
258
name string
redefineClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.4.1
name string
sun/instrument
type FrameType
Native
…
truncated boolean
false
startTime long: millis
1435979800
Example event data values and properties
classCount int
1
redefinitionId ulong
2
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/instrument/ClassDefinition;)V
hidden boolean
false
modifiers int
258
name string
redefineClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.4.1
name string
sun/instrument
type FrameType
Native
…
truncated boolean
false
startTime long: millis
1005987111
Example event data values and properties
classCount int
1
redefinitionId ulong
2
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/instrument/ClassDefinition;)V
hidden boolean
false
modifiers int
258
name string
redefineClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.4.1
name string
sun/instrument
type FrameType
Native
…
truncated boolean
false
startTime long: millis
1345889791

RetransformClasses

default profiling startTime duration eventThread stackTrace 15 17 21 25 27 28

Category: Java Virtual Machine / Class Loading

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/prims/jvmtiEnv.cpp:

      class_definitions[index].class_byte_count = (jint)reconstituter.class_file_size();
      class_definitions[index].class_bytes      = (unsigned char*)
                                                       reconstituter.class_file_bytes();
    } else {
      // it is cached, get it from the cache
      class_definitions[index].class_byte_count = ik->get_cached_class_file_len();
      class_definitions[index].class_bytes      = ik->get_cached_class_file_bytes();
    }
    class_definitions[index].klass              = jcls;
  }
  EventRetransformClasses event;
  VM_RedefineClasses op(class_count, class_definitions, jvmti_class_load_kind_retransform);
  VMThread::execute(&op);
  jvmtiError error = op.check_error();
  if (error == JVMTI_ERROR_NONE) {
    event.set_classCount(class_count);
    event.set_redefinitionId(op.id());
    event.commit();
  }
  return error;
} /* end RetransformClasses */

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 0 ms
profiling true true 0 ms

Event fields with their types and descriptions
Field Type Description
classCount int Class Count
redefinitionId ulong Class Redefinition Id

Examples 3
Example event data values and properties
classCount int
1
redefinitionId ulong
1
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/Class;)V
hidden boolean
false
modifiers int
258
name string
retransformClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.4.1
name string
sun/instrument
type FrameType
Native
…
truncated boolean
false
startTime long: millis
997679097
Example event data values and properties
classCount int
1
redefinitionId ulong
1
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/Class;)V
hidden boolean
false
modifiers int
258
name string
retransformClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.4.1
name string
sun/instrument
type FrameType
Native
…
truncated boolean
false
startTime long: millis
1331982897
Example event data values and properties
classCount int
1
redefinitionId ulong
1
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/Class;)V
hidden boolean
false
modifiers int
258
name string
retransformClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.4.1
name string
sun/instrument
type FrameType
Native
…
truncated boolean
false
startTime long: millis
1426353273

ClassUnload

startTime eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Class Loading

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/oops/instanceKlass.cpp:

  ClassLoadingService::notify_class_unloaded(ik);

  SystemDictionaryShared::handle_class_unloading(ik);

  if (log_is_enabled(Info, class, unload)) {
    ResourceMark rm;
    log_info(class, unload)("unloading class %s " PTR_FORMAT, ik->external_name(), p2i(ik));
  }

  Events::log_class_unloading(Thread::current(), ik);

#if INCLUDE_JFR
  assert(ik != nullptr, "invariant");
  EventClassUnload event;
  event.set_unloadedClass(ik);
  event.set_definingClassLoader(ik->class_loader_data());
  event.commit();
#endif
}

static void method_release_C_heap_structures(Method* m) {
  m->release_C_heap_structures();
}

// Called also by InstanceKlass::deallocate_contents, with false for release_sub_metadata.

Event configuration settings across JFR profiles
Configuration enabled
default false
profiling false

Event fields with their types and descriptions
Field Type Description
unloadedClass Class Unloaded Class
definingClassLoader ClassLoader Defining Class Loader

Examples 3
Example event data values and properties
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
0
name string
jfr_sample/Main$2
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
startTime long: millis
1732344492
unloadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
0
name string
jfr_sample/Main$2
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
hidden boolean
false
modifiers int
1
name string
jfr_sample/Unloadable2178494533369
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
0
name string
jfr_sample/Main$2
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
location string
null
name string
null
version string
null
name string
jfr_sample
Example event data values and properties
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
startTime long: millis
485542233533
unloadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
true
modifiers int
4112
name string
org.renaissance.jdk.streams.MnemonicsCoderWithStream$$Lambda/0x000000008db11c00
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/renaissance/jdk/streams
Example event data values and properties
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
startTime long: millis
492449335325
unloadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
true
modifiers int
4112
name string
dotty.tools.dotc.config.WarningSettings$WunusedHas$$$Lambda/0x000000008328d000
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
dotty/tools/dotc/config

JVM: Code Cache

CodeCacheFull

default profiling startTime eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Code Cache

A code heap is full, this leads to disabling the compiler

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/code/codeCache.cpp:

    {
      ttyLocker ttyl;
      tty->print("%s", s.freeze());
    }

    if (full_count == 1) {
      if (PrintCodeHeapAnalytics) {
        CompileBroker::print_heapinfo(tty, "all", 4096); // details, may be a lot!
      }
    }
  }

  EventCodeCacheFull event;
  if (event.should_commit()) {
    event.set_codeBlobType((u1)code_blob_type);
    event.set_startAddress((u8)heap->low_boundary());
    event.set_commitedTopAddress((u8)heap->high());
    event.set_reservedTopAddress((u8)heap->high_boundary());
    event.set_entryCount(heap->blob_count());
    event.set_methodCount(heap->nmethod_count());
    event.set_adaptorCount(heap->adapter_count());
    event.set_unallocatedCapacity(heap->unallocated_capacity());
    event.set_fullCount(heap->full_count());
    event.set_codeCacheMaxCapacity(CodeCache::max_capacity());

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
codeBlobType CodeBlobType Code Heap
startAddress ulong: address Start Address
commitedTopAddress ulong: address Commited Top
reservedTopAddress ulong: address Reserved Top
entryCount int Entries
methodCount int Methods
adaptorCount int Adaptors
unallocatedCapacity ulong: bytes Unallocated
fullCount int Full Count
codeCacheMaxCapacity ulong: bytes 17+ Code Cache Maximum Capacity

CodeCacheStatistics

default profiling startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Code Cache

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

TRACE_REQUEST_FUNC(CompilerConfiguration) {
  EventCompilerConfiguration event;
  event.set_threadCount(static_cast<s4>(CICompilerCount));
  event.set_tieredCompilation(TieredCompilation);
  event.set_dynamicCompilerThreadCount(UseDynamicNumberOfCompilerThreads);
  event.commit();
}

TRACE_REQUEST_FUNC(CodeCacheStatistics) {
  // Emit stats for all available code heaps
  for (int bt_index = 0; bt_index < static_cast<int>(CodeBlobType::NumTypes); ++bt_index) {
    const CodeBlobType bt = static_cast<CodeBlobType>(bt_index);
    if (CodeCache::heap_available(bt)) {
      EventCodeCacheStatistics event;
      event.set_codeBlobType((u1)bt);
      event.set_startAddress((u8)CodeCache::low_bound(bt));
      event.set_reservedTopAddress((u8)CodeCache::high_bound(bt));
      event.set_entryCount(CodeCache::blob_count(bt));
      event.set_methodCount(CodeCache::nmethod_count(bt));
      event.set_adaptorCount(CodeCache::adapter_count(bt));
      event.set_unallocatedCapacity(CodeCache::unallocated_capacity(bt));
      event.set_fullCount(CodeCache::get_codemem_full_count(bt));
      event.commit();
    }
  }

Event configuration settings across JFR profiles
Configuration enabled period
default true everyChunk
profiling true everyChunk

Event fields with their types and descriptions
Field Type Description
codeBlobType CodeBlobType Code Heap
startAddress ulong: address Start Address
reservedTopAddress ulong: address Reserved Top
entryCount int Entries
methodCount int Methods
adaptorCount int Adaptors
unallocatedCapacity ulong: bytes Unallocated
fullCount int Full Count

Examples 3
Example event data values and properties
adaptorCount int
2693
codeBlobType CodeBlobType
CodeHeap 'non-nmethods'
entryCount int
2791
fullCount int
0
methodCount int
0
reservedTopAddress ulong: address
140168201764864
startAddress ulong: address
140168195473408
startTime long: millis
489576292619
unallocatedCapacity ulong: bytes
2982400
Example event data values and properties
adaptorCount int
2636
codeBlobType CodeBlobType
CodeHeap 'non-nmethods'
entryCount int
2736
fullCount int
0
methodCount int
0
reservedTopAddress ulong: address
140617965371392
startAddress ulong: address
140617959079936
startTime long: millis
462141739132
unallocatedCapacity ulong: bytes
1955456
Example event data values and properties
adaptorCount int
479
codeBlobType CodeBlobType
CodeHeap 'non-nmethods'
entryCount int
575
fullCount int
0
methodCount int
0
reservedTopAddress ulong: address
140366911111168
startAddress ulong: address
140366904819712
startTime long: millis
15507421778
unallocatedCapacity ulong: bytes
4726528

CodeCacheConfiguration

default profiling startTime end of every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Code Cache

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

      event.set_startAddress((u8)CodeCache::low_bound(bt));
      event.set_reservedTopAddress((u8)CodeCache::high_bound(bt));
      event.set_entryCount(CodeCache::blob_count(bt));
      event.set_methodCount(CodeCache::nmethod_count(bt));
      event.set_adaptorCount(CodeCache::adapter_count(bt));
      event.set_unallocatedCapacity(CodeCache::unallocated_capacity(bt));
      event.set_fullCount(CodeCache::get_codemem_full_count(bt));
      event.commit();
    }
  }
}

TRACE_REQUEST_FUNC(CodeCacheConfiguration) {
  EventCodeCacheConfiguration event;
  event.set_initialSize(InitialCodeCacheSize);
  event.set_reservedSize(ReservedCodeCacheSize);
  event.set_nonNMethodSize(NonNMethodCodeHeapSize);
  event.set_profiledSize(ProfiledCodeHeapSize);
  event.set_nonProfiledSize(NonProfiledCodeHeapSize);
  event.set_expansionSize(CodeCacheExpansionSize);
  event.set_minBlockLength(CodeCacheMinBlockLength);
  event.set_startAddress((u8)CodeCache::low_bound());
  event.set_reservedTopAddress((u8)CodeCache::high_bound());
  event.commit();
}

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
initialSize ulong: bytes Initial Size
reservedSize ulong: bytes Reserved Size
nonNMethodSize ulong: bytes Non-Nmethod Size
profiledSize ulong: bytes Profiled Size
nonProfiledSize ulong: bytes Non-Profiled Size
expansionSize ulong: bytes Expansion Size
minBlockLength ulong: bytes Minimum Block Length
startAddress ulong: address Start Address
reservedTopAddress ulong: address Reserved Top

Examples 3
Example event data values and properties
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
6291456
nonProfiledSize ulong: bytes
123731968
profiledSize ulong: bytes
123731968
reservedSize ulong: bytes
253755392
reservedTopAddress ulong: address
140168325496832
startAddress ulong: address
140168071741440
startTime long: millis
473545103874
Example event data values and properties
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
6291456
nonProfiledSize ulong: bytes
123731968
profiledSize ulong: bytes
123731968
reservedSize ulong: bytes
253755392
reservedTopAddress ulong: address
140367034843136
startAddress ulong: address
140366781087744
startTime long: millis
15623181982
Example event data values and properties
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
6291456
nonProfiledSize ulong: bytes
123731968
profiledSize ulong: bytes
123731968
reservedSize ulong: bytes
253755392
reservedTopAddress ulong: address
140618089103360
startAddress ulong: address
140617835347968
startTime long: millis
496741430432

JVM: Compiler

JITRestart

default profiling startTime eventThread 17 21 25 27 28

Category: Java Virtual Machine / Compiler

Restart of the JIT compilers after they were stopped

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/code/codeCache.cpp:

    delete curr;
    curr = next;
  }
  _exception_cache_purge_list = nullptr;
}

// Restart compiler if possible and required..
void CodeCache::maybe_restart_compiler(size_t freed_memory) {

  // Try to start the compiler again if we freed any memory
  if (!CompileBroker::should_compile_new_jobs() && freed_memory != 0) {
    CompileBroker::set_should_compile_new_jobs(CompileBroker::run_compilation);
    log_info(codecache)("Restarting compiler");
    EventJITRestart event;
    event.set_freedMemory(freed_memory);
    event.set_codeCacheMaxCapacity(CodeCache::max_capacity());
    event.commit();
  }
}

uint8_t CodeCache::_unloading_cycle = 1;

void CodeCache::increment_unloading_cycle() {
  // 2-bit value (see IsUnloadingState in nmethod.cpp for details)
  // 0 is reserved for new methods.

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
freedMemory ulong: bytes Freed Memory
codeCacheMaxCapacity ulong: bytes Code Cache Maximum Capacity

Compilation

default profiling startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Compiler

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Results of method compilation attempts

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/compiler/compilerEvent.cpp:

template <typename EventType>
static inline void commit(EventType& event) {
  JavaThread* thread = JavaThread::current();
  JavaThreadState state = thread->thread_state();
  if (state == _thread_in_native) {
    ThreadInVMfromNative transition(thread);
    event.commit();
  } else {
    assert(state == _thread_in_vm, "coming from wrong thread state %d", state);
    event.commit();
  }
 }

void CompilerEvent::CompilationEvent::post(EventCompilation& event, int compile_id, CompilerType compiler_type, Method* method,
    int compile_level, bool success, bool is_osr, int code_size,
    int inlined_bytecodes, size_t arenaBytes) {
  event.set_compileId(compile_id);
  event.set_compiler(compiler_type);
  event.set_method(method);
  event.set_compileLevel((short)compile_level);
  event.set_succeded(success);
  event.set_isOsr(is_osr);
  event.set_codeSize(code_size);
  event.set_inlinedBytes(inlined_bytecodes);
  event.set_arenaBytes(arenaBytes);

src/hotspot/share/compiler/compileBroker.cpp:

void CompileBroker::handle_compile_error(CompilerThread* thread, CompileTask* task, ciEnv* ci_env,
                                         int compilable, const char* failure_reason) {
  if (!AbortVMOnCompilationFailure) {
    return;
  }
  if (compilable == ciEnv::MethodCompilable_not_at_tier) {
    fatal("Not compilable at tier %d: %s", task->comp_level(), failure_reason);
  }
  if (compilable == ciEnv::MethodCompilable_never) {
    fatal("Never compilable: %s", failure_reason);
  }
}

static void post_compilation_event(EventCompilation& event, CompileTask* task) {
  assert(task != nullptr, "invariant");
  CompilerEvent::CompilationEvent::post(event,
                                        task->compile_id(),
                                        task->compiler()->type(),
                                        task->method(),
                                        task->comp_level(),
                                        task->is_success(),
                                        task->osr_bci() != CompileBroker::standard_entry_bci,
                                        task->nm_total_size(),
                                        task->num_inlined_bytecodes(),
                                        task->arena_bytes());
}

src/hotspot/share/compiler/compileBroker.cpp:

    bool method_is_old = ci_env.cache_jvmti_state();

    // Skip redefined methods
    if (method_is_old) {
      ci_env.record_method_not_compilable("redefined method", true);
    }

    // Cache DTrace flags
    ci_env.cache_dtrace_flags();

    ciMethod* target = ci_env.get_method_from_handle(target_handle);

    TraceTime t1("compilation", &time);
    EventCompilation event;

    if (comp == nullptr) {
      ci_env.record_method_not_compilable("no compiler");
    } else if (!ci_env.failing()) {
      if (WhiteBoxAPI && WhiteBox::compilation_locked) {
        whitebox_lock_compilation();
      }
      comp->compile_method(&ci_env, target, osr_bci, true, directive);

      /* Repeat compilation without installing code for profiling purposes */
      int repeat_compilation_count = directive->RepeatCompilationOption;

src/hotspot/share/compiler/compilerEvent.hpp:

#if INCLUDE_JFR
#include "jfr/utilities/jfrTime.hpp"
#endif

class ciMethod;
template <typename>
class GrowableArray;
class Method;
class EventCompilation;
class EventCompilationFailure;
class EventCompilerInlining;
class EventCompilerPhase;
struct JfrStructCalleeMethod;

class CompilerEvent : AllStatic {
 public:
  static jlong ticksNow() {
    // Using Ticks for consistent usage outside JFR folder.
    JFR_ONLY(return JfrTime::is_ft_enabled() ? Ticks::now().ft_value() : Ticks::now().value();) NOT_JFR_RETURN_(0L);
  }

  class CompilationEvent : AllStatic {
   public:
    static void post(EventCompilation& event, int compile_id, CompilerType type, Method* method,
                     int compile_level, bool success, bool is_osr, int code_size,
                     int inlined_bytecodes, size_t arenaBytes) NOT_JFR_RETURN();
  };

  class CompilationFailureEvent : AllStatic {
   public:
    static void post(EventCompilationFailure& event, int compile_id, const char* reason) NOT_JFR_RETURN();
  };

  class PhaseEvent : AllStatic {
    friend class CompilerPhaseTypeConstant;

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 1000 ms
profiling true 100 ms

Event fields with their types and descriptions
Field Type Description
compileId int Compilation Identifier
compiler CompilerType 14+ Compiler
method Method Method
compileLevel ushort Compilation Level
succeded boolean Succeeded
isOsr boolean On Stack Replacement
codeSize ulong: bytes Compiled Code Size
inlinedBytes ulong: bytes Inlined Code Size
arenaBytes ulong: bytes 23+ Arena Usage

Examples 3
Example event data values and properties
arenaBytes ulong: bytes
0
codeSize ulong: bytes
8136
compileId int
92744
compileLevel ushort
3
compiler CompilerType
c1
inlinedBytes ulong: bytes
96
isOsr boolean
false
method Method
descriptor string
(Lorg/apache/spark/ContextCleaner;Lorg/apache/spark/CleanupTaskWeakReference;)V
hidden boolean
false
modifiers int
4121
name string
$anonfun$keepCleaning$3
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/ContextCleaner
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark
startTime long: millis
447749631965
succeded boolean
true
Example event data values and properties
arenaBytes ulong: bytes
0
codeSize ulong: bytes
2664
compileId int
1373
compileLevel ushort
3
compiler CompilerType
c1
inlinedBytes ulong: bytes
45
isOsr boolean
false
method Method
descriptor string
()Z
hidden boolean
false
modifiers int
1
name string
endEvent
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/jfr/internal/event/EventWriter
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.jfr
name string
jdk.jfr
version string
25.0.4.1
name string
jdk/jfr/internal/event
startTime long: millis
378776958
succeded boolean
true
Example event data values and properties
arenaBytes ulong: bytes
0
codeSize ulong: bytes
560
compileId int
94131
compileLevel ushort
3
compiler CompilerType
c1
inlinedBytes ulong: bytes
15
isOsr boolean
false
method Method
descriptor string
()J
hidden boolean
false
modifiers int
1
name string
resultSerializationTime
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/executor/TaskMetrics
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/executor
startTime long: millis
453479051150
succeded boolean
true

CompilerPhase

default profiling startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Compiler

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Describes various phases of the compilation process like inlining or string optimization related phases

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/compiler/compilerEvent.cpp:

  event.set_isOsr(is_osr);
  event.set_codeSize(code_size);
  event.set_inlinedBytes(inlined_bytecodes);
  event.set_arenaBytes(arenaBytes);
  commit(event);
}

void CompilerEvent::CompilationFailureEvent::post(EventCompilationFailure& event, int compile_id, const char* reason) {
  event.set_compileId(compile_id);
  event.set_failureMessage(reason);
  event.commit();
}

void CompilerEvent::PhaseEvent::post(EventCompilerPhase& event, const Ticks& start_time, int phase, int compile_id, int level) {
  event.set_starttime(start_time);
  event.set_phase((u1) phase);
  event.set_compileId(compile_id);
  event.set_phaseLevel((short)level);
  event.commit();
}

void CompilerEvent::InlineEvent::post(EventCompilerInlining& event, int compile_id, Method* caller, const JfrStructCalleeMethod& callee, bool success, const char* msg, int bci) {
  event.set_compileId(compile_id);
  event.set_caller(caller);
  event.set_callee(callee);

src/hotspot/share/compiler/compilerEvent.hpp:

#if INCLUDE_JFR
#include "jfr/utilities/jfrTime.hpp"
#endif

class ciMethod;
template <typename>
class GrowableArray;
class Method;
class EventCompilation;
class EventCompilationFailure;
class EventCompilerInlining;
class EventCompilerPhase;
struct JfrStructCalleeMethod;

class CompilerEvent : AllStatic {
 public:
  static jlong ticksNow() {
    // Using Ticks for consistent usage outside JFR folder.
    JFR_ONLY(return JfrTime::is_ft_enabled() ? Ticks::now().ft_value() : Ticks::now().value();) NOT_JFR_RETURN_(0L);
  }

  class CompilationEvent : AllStatic {
   public:

src/hotspot/share/compiler/compilerEvent.hpp:

  class PhaseEvent : AllStatic {
    friend class CompilerPhaseTypeConstant;
   public:

    // Gets a unique identifier for `phase_name`, computing and registering it first if necessary.
    // If `may_exist` is true, then current registrations are searched first. If false, then
    // there must not be an existing registration for `phase_name`.
    // If `use_strdup` is true, then `phase_name` is strdup'ed before registration.
    // If `sync` is true, then access to the registration table is synchronized.
    static int get_phase_id(const char* phase_name, bool may_exist, bool use_strdup, bool sync) NOT_JFR_RETURN_(-1);

    static void post(EventCompilerPhase& event, const Ticks& start_time, int phase, int compile_id, int level) NOT_JFR_RETURN();
    static void post(EventCompilerPhase& event, jlong start_time, int phase, int compile_id, int level) {
      JFR_ONLY(post(event, Ticks(start_time), phase, compile_id, level);)
    }
  };

  class InlineEvent : AllStatic {
    static void post(EventCompilerInlining& event, int compile_id, Method* caller, const JfrStructCalleeMethod& callee, bool success, const char* msg, int bci) NOT_JFR_RETURN();
   public:
    static void post(EventCompilerInlining& event, int compile_id, Method* caller, Method* callee, bool success, const char* msg, int bci) NOT_JFR_RETURN();
    static void post(EventCompilerInlining& event, int compile_id, Method* caller, ciMethod* callee, bool success, const char* msg, int bci) NOT_JFR_RETURN();
  };
};

src/hotspot/share/opto/compile.cpp:

    if (n->is_Allocate()) {
      if (i != allocates) {
        Node* tmp = macro_node(allocates);
        _macro_nodes.at_put(allocates, n);
        _macro_nodes.at_put(i, tmp);
      }
      allocates++;
    }
  }
}

void Compile::print_method(CompilerPhaseType compile_phase, int level, Node* n) {
  if (failing_internal()) { return; } // failing_internal to not stress bailouts from printing code.
  EventCompilerPhase event(UNTIMED);
  if (event.should_commit()) {
    CompilerEvent::PhaseEvent::post(event, C->_latest_stage_start_counter, compile_phase, C->_compile_id, level);
  }
#ifndef PRODUCT
  ResourceMark rm;
  stringStream ss;
  ss.print_raw(CompilerPhaseTypeHelper::to_description(compile_phase));
  int iter = ++_igv_phase_iter[compile_phase];
  if (iter > 1) {
    ss.print(" %d", iter);
  }

src/hotspot/share/opto/compile.cpp:

// Only used from CompileWrapper
void Compile::begin_method() {
#ifndef PRODUCT
  if (_method != nullptr && should_print_igv(1)) {
    _igv_printer->begin_method();
  }
#endif
  C->_latest_stage_start_counter.stamp();
}

// Only used from CompileWrapper
void Compile::end_method() {
  EventCompilerPhase event(UNTIMED);
  if (event.should_commit()) {
    CompilerEvent::PhaseEvent::post(event, C->_latest_stage_start_counter, PHASE_END, C->_compile_id, 1);
  }

#ifndef PRODUCT
  if (_method != nullptr && should_print_igv(1)) {
    _igv_printer->end_method();
  }
#endif
}

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 60 s
profiling true 10 s

Event fields with their types and descriptions
Field Type Description
phase CompilerPhaseType Compile Phase
compileId int Compilation Identifier
phaseLevel ushort Phase Level

Examples 3
Example event data values and properties
compileId int
1362
phase CompilerPhaseType
After Loop Optimizations
phaseLevel ushort
2
startTime long: millis
363824114
Example event data values and properties
compileId int
92732
phase CompilerPhaseType
Iter GVN 2
phaseLevel ushort
2
startTime long: millis
447748229152
Example event data values and properties
compileId int
94089
phase CompilerPhaseType
Before Iter GVN
phaseLevel ushort
3
startTime long: millis
453371465997

CompilationFailure

profiling startTime eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Compiler

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

In case a JIT compilation failed, a compilation failure is triggered, reporting the reason

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/compiler/compilerEvent.cpp:

    int inlined_bytecodes, size_t arenaBytes) {
  event.set_compileId(compile_id);
  event.set_compiler(compiler_type);
  event.set_method(method);
  event.set_compileLevel((short)compile_level);
  event.set_succeded(success);
  event.set_isOsr(is_osr);
  event.set_codeSize(code_size);
  event.set_inlinedBytes(inlined_bytecodes);
  event.set_arenaBytes(arenaBytes);
  commit(event);
}

void CompilerEvent::CompilationFailureEvent::post(EventCompilationFailure& event, int compile_id, const char* reason) {
  event.set_compileId(compile_id);
  event.set_failureMessage(reason);
  event.commit();
}

void CompilerEvent::PhaseEvent::post(EventCompilerPhase& event, const Ticks& start_time, int phase, int compile_id, int level) {
  event.set_starttime(start_time);
  event.set_phase((u1) phase);
  event.set_compileId(compile_id);
  event.set_phaseLevel((short)level);
  event.commit();

src/hotspot/share/compiler/compilerEvent.hpp:

#if INCLUDE_JFR
#include "jfr/utilities/jfrTime.hpp"
#endif

class ciMethod;
template <typename>
class GrowableArray;
class Method;
class EventCompilation;
class EventCompilationFailure;
class EventCompilerInlining;
class EventCompilerPhase;
struct JfrStructCalleeMethod;

class CompilerEvent : AllStatic {
 public:
  static jlong ticksNow() {
    // Using Ticks for consistent usage outside JFR folder.
    JFR_ONLY(return JfrTime::is_ft_enabled() ? Ticks::now().ft_value() : Ticks::now().value();) NOT_JFR_RETURN_(0L);
  }

  class CompilationEvent : AllStatic {
   public:
    static void post(EventCompilation& event, int compile_id, CompilerType type, Method* method,
                     int compile_level, bool success, bool is_osr, int code_size,
                     int inlined_bytecodes, size_t arenaBytes) NOT_JFR_RETURN();
  };

  class CompilationFailureEvent : AllStatic {
   public:
    static void post(EventCompilationFailure& event, int compile_id, const char* reason) NOT_JFR_RETURN();
  };

  class PhaseEvent : AllStatic {
    friend class CompilerPhaseTypeConstant;
   public:

    // Gets a unique identifier for `phase_name`, computing and registering it first if necessary.
    // If `may_exist` is true, then current registrations are searched first. If false, then
    // there must not be an existing registration for `phase_name`.
    // If `use_strdup` is true, then `phase_name` is strdup'ed before registration.
    // If `sync` is true, then access to the registration table is synchronized.

src/hotspot/share/ci/ciEnv.cpp:

      CompilerThread* thread = CompilerThread::current();
      CompileTask* task = thread->task();
      CompilationLog::log()->log_failure(thread, task, reason, nullptr);
    }
  }

  if (_failure_reason.get() == nullptr) {
    // Record the first failure reason.
    _failure_reason.set(reason);
  }
}

void ciEnv::report_failure(const char* reason) {
  EventCompilationFailure event;
  if (event.should_commit()) {
    CompilerEvent::CompilationFailureEvent::post(event, compile_id(), reason);
  }
}

// ------------------------------------------------------------------
// ciEnv::record_method_not_compilable()
void ciEnv::record_method_not_compilable(const char* reason, bool all_tiers) {
  int new_compilable =
    all_tiers ? MethodCompilable_never : MethodCompilable_not_at_tier ;

  // Only note transitions to a worse state
  if (new_compilable > _compilable) {

Event configuration settings across JFR profiles
Configuration enabled
default false
profiling true

Event fields with their types and descriptions
Field Type Description
failureMessage string Failure Message
compileId int Compilation Identifier

Examples 3
Example event data values and properties
compileId int
97545
failureMessage string
retry without subsuming loads
startTime long: millis
482996133969
Example event data values and properties
compileId int
2606
failureMessage string
Jvmti state change invalidated dependencies
startTime long: millis
1482637230
Example event data values and properties
compileId int
109312
failureMessage string
retry without subsuming loads
startTime long: millis
497701076143

CompilerInlining

startTime eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Compiler / Optimization

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Describes the result of a method inlining attempt

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/c1/c1_GraphBuilder.cpp:

  append(new MemBar(lir_membar_storestore));
}

void GraphBuilder::print_inlining(ciMethod* callee, const char* msg, bool success) {
  CompileLog* log = compilation()->log();
  if (log != nullptr) {
    assert(msg != nullptr, "inlining msg should not be null!");
    if (success) {
      log->inline_success(msg);
    } else {
      log->inline_fail(msg);
    }
  }
  EventCompilerInlining event;
  if (event.should_commit()) {
    CompilerEvent::InlineEvent::post(event, compilation()->env()->task()->compile_id(), method()->get_Method(), callee, success, msg, bci());
  }

  CompileTask::print_inlining_ul(callee, scope()->level(), bci(), inlining_result_of(success), msg);

  if (!compilation()->directive()->PrintInliningOption) {
    return;
  }
  CompileTask::print_inlining_tty(callee, scope()->level(), bci(), inlining_result_of(success), msg);
  if (success && CIPrintMethodCodes) {

src/hotspot/share/compiler/compilerEvent.cpp:

  event.set_compileId(compile_id);
  event.set_failureMessage(reason);
  event.commit();
}

void CompilerEvent::PhaseEvent::post(EventCompilerPhase& event, const Ticks& start_time, int phase, int compile_id, int level) {
  event.set_starttime(start_time);
  event.set_phase((u1) phase);
  event.set_compileId(compile_id);
  event.set_phaseLevel((short)level);
  event.commit();
}

void CompilerEvent::InlineEvent::post(EventCompilerInlining& event, int compile_id, Method* caller, const JfrStructCalleeMethod& callee, bool success, const char* msg, int bci) {
  event.set_compileId(compile_id);
  event.set_caller(caller);
  event.set_callee(callee);
  event.set_succeeded(success);
  event.set_message(msg);
  event.set_bci(bci);
  commit(event);
}

void CompilerEvent::InlineEvent::post(EventCompilerInlining& event, int compile_id, Method* caller, Method* callee, bool success, const char* msg, int bci) {
  JfrStructCalleeMethod callee_struct;
  callee_struct.set_type(callee->klass_name()->as_utf8());
  callee_struct.set_name(callee->name()->as_utf8());
  callee_struct.set_descriptor(callee->signature()->as_utf8());
  post(event, compile_id, caller, callee_struct, success, msg, bci);
}

void CompilerEvent::InlineEvent::post(EventCompilerInlining& event, int compile_id, Method* caller, ciMethod* callee, bool success, const char* msg, int bci) {
  JfrStructCalleeMethod callee_struct;
  callee_struct.set_type(callee->holder()->name()->as_utf8());
  callee_struct.set_name(callee->name()->as_utf8());
  callee_struct.set_descriptor(callee->signature()->as_symbol()->as_utf8());
  post(event, compile_id, caller, callee_struct, success, msg, bci);
}

src/hotspot/share/compiler/compilerEvent.hpp:

#if INCLUDE_JFR
#include "jfr/utilities/jfrTime.hpp"
#endif

class ciMethod;
template <typename>
class GrowableArray;
class Method;
class EventCompilation;
class EventCompilationFailure;
class EventCompilerInlining;
class EventCompilerPhase;
struct JfrStructCalleeMethod;

class CompilerEvent : AllStatic {
 public:
  static jlong ticksNow() {
    // Using Ticks for consistent usage outside JFR folder.
    JFR_ONLY(return JfrTime::is_ft_enabled() ? Ticks::now().ft_value() : Ticks::now().value();) NOT_JFR_RETURN_(0L);
  }

  class CompilationEvent : AllStatic {

src/hotspot/share/compiler/compilerEvent.hpp:

    friend class CompilerPhaseTypeConstant;
   public:

    // Gets a unique identifier for `phase_name`, computing and registering it first if necessary.
    // If `may_exist` is true, then current registrations are searched first. If false, then
    // there must not be an existing registration for `phase_name`.
    // If `use_strdup` is true, then `phase_name` is strdup'ed before registration.
    // If `sync` is true, then access to the registration table is synchronized.
    static int get_phase_id(const char* phase_name, bool may_exist, bool use_strdup, bool sync) NOT_JFR_RETURN_(-1);

    static void post(EventCompilerPhase& event, const Ticks& start_time, int phase, int compile_id, int level) NOT_JFR_RETURN();
    static void post(EventCompilerPhase& event, jlong start_time, int phase, int compile_id, int level) {
      JFR_ONLY(post(event, Ticks(start_time), phase, compile_id, level);)
    }
  };

  class InlineEvent : AllStatic {
    static void post(EventCompilerInlining& event, int compile_id, Method* caller, const JfrStructCalleeMethod& callee, bool success, const char* msg, int bci) NOT_JFR_RETURN();
   public:
    static void post(EventCompilerInlining& event, int compile_id, Method* caller, Method* callee, bool success, const char* msg, int bci) NOT_JFR_RETURN();
    static void post(EventCompilerInlining& event, int compile_id, Method* caller, ciMethod* callee, bool success, const char* msg, int bci) NOT_JFR_RETURN();
  };
};
#endif // SHARE_COMPILER_COMPILEREVENT_HPP

src/hotspot/share/opto/bytecodeInfo.cpp:

  int caller_bci = jvm->bci();
  ciMethod* caller_method = jvm->method();
  const char* inline_msg = msg();
  assert(inline_msg != nullptr, "just checking");
  if (C->log() != nullptr) {
    if (success) {
      C->log()->inline_success(inline_msg);
    } else {
      C->log()->inline_fail(inline_msg);
    }
  }
  CompileTask::print_inlining_ul(callee_method, inline_level(), caller_bci, inlining_result_of(success), inline_msg);
  C->inline_printer()->record(callee_method, jvm, inlining_result_of(success), inline_msg);
  EventCompilerInlining event;
  if (event.should_commit()) {
    guarantee(callee_method != nullptr, "would crash in CompilerEvent::InlineEvent::post");
    CompilerEvent::InlineEvent::post(event, C->compile_id(), caller_method->get_Method(), callee_method, success, inline_msg, caller_bci);
  }
}

//------------------------------ok_to_inline-----------------------------------
bool InlineTree::ok_to_inline(ciMethod* callee_method, JVMState* jvms, ciCallProfile& profile,
                              bool& should_delay) {
#ifdef ASSERT
  assert(callee_method != nullptr, "caller checks for optimized virtual!");

Event configuration settings across JFR profiles
Configuration enabled
default false
profiling false

Event fields with their types and descriptions
Field Type Description
compileId int Compilation Identifier
caller Method Caller Method
callee CalleeMethod struct Callee Method
succeeded boolean Succeeded
message string Message
bci int Bytecode Index

Examples 3
Example event data values and properties
bci int
2604
callee CalleeMethod
descriptor string
(DDLorg/netlib/util/doubleW;Lorg/netlib/util/doubleW;Lorg/netlib/util/doubleW;)V
name string
dlartg
type string
org/netlib/lapack/Dlartg
caller Method
descriptor string
(Ljava/lang/String;I[DI[DI[DII[DILorg/netlib/util/intW;)V
hidden boolean
false
modifiers int
9
name string
dsteqr
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
org/netlib/lapack/Dsteqr
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/netlib/lapack
compileId int
92746
message string
hot method too big
startTime long: millis
447753522709
succeeded boolean
false
Example event data values and properties
bci int
7
callee CalleeMethod
descriptor string
([BI)C
name string
getChar
type string
java/lang/StringUTF16
caller Method
descriptor string
([BI)C
hidden boolean
false
modifiers int
9
name string
charAt
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
16
name string
java/lang/StringUTF16
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
compileId int
1357
message string
intrinsic
startTime long: millis
363673847
succeeded boolean
true
Example event data values and properties
bci int
26
callee CalleeMethod
descriptor string
()I
name string
length
type string
java/lang/String
caller Method
descriptor string
(ILjava/lang/String;II)Z
hidden boolean
false
modifiers int
1
name string
regionMatches
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/String
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
compileId int
94089
message string
inline (hot)
startTime long: millis
453365282000
succeeded boolean
true

Deoptimization

default profiling startTime eventThread stackTrace 14 17 21 25 27 28

Category: Java Virtual Machine / Compiler

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Describes the detection of an uncommon situation in a compiled method which may lead to deoptimization of the method

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/deoptimization.cpp:

  JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONREASON, true, new DeoptReasonSerializer());
  JfrSerializer::register_serializer(TYPE_DEOPTIMIZATIONACTION, true, new DeoptActionSerializer());
}

static void post_deoptimization_event(nmethod* nm,
                                      const Method* method,
                                      int trap_bci,
                                      int instruction,
                                      Deoptimization::DeoptReason reason,
                                      Deoptimization::DeoptAction action) {
  assert(nm != nullptr, "invariant");
  assert(method != nullptr, "invariant");
  if (EventDeoptimization::is_enabled()) {
    static bool serializers_registered = false;
    if (!serializers_registered) {
      register_serializers();
      serializers_registered = true;
    }
    EventDeoptimization event;
    event.set_compileId(nm->compile_id());
    event.set_compiler(nm->compiler_type());
    event.set_method(method);
    event.set_lineNumber(method->line_number_from_bci(trap_bci));
    event.set_bci(trap_bci);
    event.set_instruction(instruction);
    event.set_reason(reason);
    event.set_action(action);
    event.commit();
  }
}

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default true false
profiling true true

Event fields with their types and descriptions
Field Type Description
compileId int Compilation Identifier
compiler CompilerType Compiler
method Method Method
lineNumber int Line Number
bci int Bytecode Index
instruction Bytecode Instruction
reason DeoptimizationReason Reason
action DeoptimizationAction Action

Examples 3
Example event data values and properties
action DeoptimizationAction
reinterpret
bci int
2
compileId int
1806
compiler CompilerType
c2
instruction Bytecode
tableswitch
lineNumber int
364
method Method
descriptor string
(Ljava/lang/Object;IIII)I
hidden boolean
false
modifiers int
10
name string
vectorizedHashCode
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
jdk/internal/util/ArraysSupport
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/util
reason DeoptimizationReason
unstable_if
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
2
lineNumber int
364
method Method
descriptor string
(Ljava/lang/Object;IIII)I
hidden boolean
false
modifiers int
10
name string
vectorizedHashCode
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
jdk/internal/util/ArraysSupport
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/util
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
886113773
Example event data values and properties
action DeoptimizationAction
maybe_recompile
bci int
11
compileId int
96080
compiler CompilerType
c2
instruction Bytecode
invokeinterface
lineNumber int
477
method Method
descriptor string
()Z
hidden boolean
false
modifiers int
1
name string
hasNext
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
scala/collection/Iterator$$anon$6
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection
reason DeoptimizationReason
bimorphic_or_optimized_type_check
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
11
lineNumber int
477
method Method
descriptor string
()Z
hidden boolean
false
modifiers int
1
name string
hasNext
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
scala/collection/Iterator$$anon$6
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
482413099795
Example event data values and properties
action DeoptimizationAction
maybe_recompile
bci int
93
compileId int
94835
compiler CompilerType
c2
instruction Bytecode
aastore
lineNumber int
979
method Method
descriptor string
(ILjava/util/concurrent/RunnableScheduledFuture;)V
hidden boolean
false
modifiers int
2
name string
siftDown
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
8
name string
java/util/concurrent/ScheduledThreadPoolExecutor$DelayedWorkQueue
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent
reason DeoptimizationReason
array_check
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
93
lineNumber int
979
method Method
descriptor string
(ILjava/util/concurrent/RunnableScheduledFuture;)V
hidden boolean
false
modifiers int
2
name string
siftDown
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
8
name string
java/util/concurrent/ScheduledThreadPoolExecutor$DelayedWorkQueue
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
459257157938

CompilerQueueUtilization

default profiling startTime duration every chunk 22 25 27 28

Category: Java Virtual Machine / Compiler

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrCompilerQueueUtilization.cpp:

    {CompileBroker::c2_compile_queue(), c2_compiler_queue_id, &CompileBroker::get_c2_thread_count, 0, 0}};

  const JfrTicks cur_time = JfrTicks::now();
  static JfrTicks last_sample_instant;
  const JfrTickspan interval = cur_time - last_sample_instant;
  for (int i = 0; i < num_compiler_queues; i ++) {
    CompilerQueueEntry* entry = &compilerQueueEntries[i];
    if (entry->compilerQueue != nullptr) {
      const uint64_t current_added = entry->compilerQueue->get_total_added();
      const uint64_t current_removed = entry->compilerQueue->get_total_removed();
      const uint64_t addedRate = rate_per_second(current_added, entry->added, interval);
      const uint64_t removedRate = rate_per_second(current_removed, entry->removed, interval);

      EventCompilerQueueUtilization event;
      event.set_compiler(entry->compiler_queue_id);
      event.set_addedRate(addedRate);
      event.set_removedRate(removedRate);
      event.set_queueSize(entry->compilerQueue->size());
      event.set_peakQueueSize(entry->compilerQueue->get_peak_size());
      event.set_addedCount(current_added - entry->added);
      event.set_removedCount(current_removed - entry->removed);
      event.set_totalAddedCount(current_added);
      event.set_totalRemovedCount(current_removed);
      event.set_compilerThreadCount(entry->get_compiler_thread_count());
      event.commit();

Event configuration settings across JFR profiles
Configuration enabled period
default true 10 s
profiling true 5 s

Event fields with their types and descriptions
Field Type Description
compiler CompilerType Compiler
addedRate long: hertz Requets Added Rate Requests added per second
removedRate long: hertz Requests Removed Rate Requests removed per second
queueSize long Queue Size
peakQueueSize long Peak Queue Size
addedCount long Requests Added
removedCount long Requests Removed
totalAddedCount long Total Requests Added
totalRemovedCount long Total Requests Removed
compilerThreadCount int Compiler Thread Count

Examples 3
Example event data values and properties
addedCount long
301
addedRate long: hertz
30
compiler CompilerType
c2
compilerThreadCount int
1
peakQueueSize long
173
queueSize long
0
removedCount long
303
removedRate long: hertz
31
startTime long: millis
455798001799
totalAddedCount long
18411
totalRemovedCount long
18411
Example event data values and properties
addedCount long
2366
addedRate long: hertz
434
compiler CompilerType
c1
compilerThreadCount int
1
peakQueueSize long
19
queueSize long
0
removedCount long
2366
removedRate long: hertz
434
startTime long: millis
5447573899
totalAddedCount long
2366
totalRemovedCount long
2366
Example event data values and properties
addedCount long
59
addedRate long: hertz
6
compiler CompilerType
c2
compilerThreadCount int
1
peakQueueSize long
246
queueSize long
0
removedCount long
59
removedRate long: hertz
6
startTime long: millis
482853444080
totalAddedCount long
19029
totalRemovedCount long
19029

CompilerStatistics

default profiling startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Compiler

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

TRACE_REQUEST_FUNC(SymbolTableStatistics) {
  TableStatistics statistics = SymbolTable::get_table_statistics();
  emit_table_statistics<EventSymbolTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(StringTableStatistics) {
  TableStatistics statistics = StringTable::get_table_statistics();
  emit_table_statistics<EventStringTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(CompilerStatistics) {
  EventCompilerStatistics event;
  event.set_compileCount(CompileBroker::get_total_compile_count());
  event.set_bailoutCount(CompileBroker::get_total_bailout_count());
  event.set_invalidatedCount(CompileBroker::get_total_invalidated_count());
  event.set_osrCompileCount(CompileBroker::get_total_osr_compile_count());
  event.set_standardCompileCount(CompileBroker::get_total_standard_compile_count());
  event.set_osrBytesCompiled(CompileBroker::get_sum_osr_bytes_compiled());
  event.set_standardBytesCompiled(CompileBroker::get_sum_standard_bytes_compiled());
  event.set_nmethodsSize(CompileBroker::get_sum_nmethod_size());
  event.set_nmethodCodeSize(CompileBroker::get_sum_nmethod_code_size());
  event.set_peakTimeSpent(CompileBroker::get_peak_compilation_time());
  event.set_totalTimeSpent(CompileBroker::get_total_compilation_time());

Event configuration settings across JFR profiles
Configuration enabled period
default true 1000 ms
profiling true 1000 ms

Event fields with their types and descriptions
Field Type Description
compileCount int Compiled Methods
bailoutCount int Bailouts
invalidatedCount int Invalidated Compilations
osrCompileCount int OSR Compilations
standardCompileCount int Standard Compilations
osrBytesCompiled ulong: bytes OSR Bytes Compiled
standardBytesCompiled ulong: bytes Standard Bytes Compiled
nmethodsSize ulong: bytes Compilation Resulting Size
nmethodCodeSize ulong: bytes Compilation Resulting Code Size
peakTimeSpent long: millis Peak Time
totalTimeSpent long: millis Total Time

Examples 3
Example event data values and properties
bailoutCount int
9
compileCount int
92464
invalidatedCount int
0
nmethodCodeSize ulong: bytes
142779952
nmethodsSize ulong: bytes
201347472
osrBytesCompiled ulong: bytes
0
osrCompileCount int
1037
peakTimeSpent long: millis
8163
standardBytesCompiled ulong: bytes
0
standardCompileCount int
91427
startTime long: millis
453272373897
totalTimeSpent long: millis
426439
Example event data values and properties
bailoutCount int
2
compileCount int
2481
invalidatedCount int
0
nmethodCodeSize ulong: bytes
3393984
nmethodsSize ulong: bytes
4582456
osrBytesCompiled ulong: bytes
0
osrCompileCount int
12
peakTimeSpent long: millis
177
standardBytesCompiled ulong: bytes
0
standardCompileCount int
2469
startTime long: millis
1332754390
totalTimeSpent long: millis
1882
Example event data values and properties
bailoutCount int
7
compileCount int
92731
invalidatedCount int
0
nmethodCodeSize ulong: bytes
132833112
nmethodsSize ulong: bytes
191084168
osrBytesCompiled ulong: bytes
0
osrCompileCount int
1023
peakTimeSpent long: millis
27428
standardBytesCompiled ulong: bytes
0
standardCompileCount int
91708
startTime long: millis
458021021934
totalTimeSpent long: millis
742293

CompilerConfiguration

default profiling startTime end of every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Compiler

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  event.set_invalidatedCount(CompileBroker::get_total_invalidated_count());
  event.set_osrCompileCount(CompileBroker::get_total_osr_compile_count());
  event.set_standardCompileCount(CompileBroker::get_total_standard_compile_count());
  event.set_osrBytesCompiled(CompileBroker::get_sum_osr_bytes_compiled());
  event.set_standardBytesCompiled(CompileBroker::get_sum_standard_bytes_compiled());
  event.set_nmethodsSize(CompileBroker::get_sum_nmethod_size());
  event.set_nmethodCodeSize(CompileBroker::get_sum_nmethod_code_size());
  event.set_peakTimeSpent(CompileBroker::get_peak_compilation_time());
  event.set_totalTimeSpent(CompileBroker::get_total_compilation_time());
  event.commit();
}

TRACE_REQUEST_FUNC(CompilerConfiguration) {
  EventCompilerConfiguration event;
  event.set_threadCount(static_cast<s4>(CICompilerCount));
  event.set_tieredCompilation(TieredCompilation);
  event.set_dynamicCompilerThreadCount(UseDynamicNumberOfCompilerThreads);
  event.commit();
}

TRACE_REQUEST_FUNC(CodeCacheStatistics) {
  // Emit stats for all available code heaps
  for (int bt_index = 0; bt_index < static_cast<int>(CodeBlobType::NumTypes); ++bt_index) {
    const CodeBlobType bt = static_cast<CodeBlobType>(bt_index);
    if (CodeCache::heap_available(bt)) {

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
threadCount int Thread Count
tieredCompilation boolean Tiered Compilation
dynamicCompilerThreadCount boolean 20+ Uses Dynamic Number of Compiler Threads

Examples 3
Example event data values and properties
dynamicCompilerThreadCount boolean
true
startTime long: millis
451440158905
threadCount int
3
tieredCompilation boolean
true
Example event data values and properties
dynamicCompilerThreadCount boolean
true
startTime long: millis
496741379647
threadCount int
3
tieredCompilation boolean
true
Example event data values and properties
dynamicCompilerThreadCount boolean
true
startTime long: millis
15623177304
threadCount int
3
tieredCompilation boolean
true

JVM: Diagnostics

SyncOnValueBasedClass

experimental default profiling startTime eventThread stackTrace 16 17 21 25 27 28

Category: Java Virtual Machine / Diagnostics

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/synchronizer.cpp:

  } else {
    assert(DiagnoseSyncOnValueBasedClasses == LOG_WARNING, "invalid value for DiagnoseSyncOnValueBasedClasses");
    ResourceMark rm;
    Log(valuebasedclasses) vblog;

    vblog.info("Synchronizing on object " INTPTR_FORMAT " of klass %s", p2i(obj()), obj->klass()->external_name());
    if (locking_thread->has_last_Java_frame()) {
      LogStream info_stream(vblog.info());
      locking_thread->print_active_stack_on(&info_stream);
    } else {
      vblog.info("Cannot find the last Java frame");
    }

    EventSyncOnValueBasedClass event;
    if (event.should_commit()) {
      event.set_valueBasedClass(obj->klass());
      event.commit();
    }
  }

  if (bcp_was_adjusted) {
    last_frame.interpreter_frame_set_bcp(last_frame.interpreter_frame_bcp() + 1);
  }
}

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default true true
profiling true true

Event fields with their types and descriptions
Field Type Description
valueBasedClass Class Value Based Class

Examples 3
Example event data values and properties
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
56
lineNumber int
300
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
triggerSyncOnValueBased
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1013868948
valueBasedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Long
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
Example event data values and properties
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
17
lineNumber int
296
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
triggerSyncOnValueBased
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1445639970
valueBasedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Integer
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
Example event data values and properties
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
17
lineNumber int
296
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
triggerSyncOnValueBased
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1419766397
valueBasedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Integer
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang

HeapDump

default profiling startTime duration eventThread stackTrace 15 17 21 25 27 28

Category: Java Virtual Machine / Diagnostics

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Information about a successfully written Java heap dump

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/services/heapDumper.cpp:

    // (DumpWriter buffer, DumperClassCacheTable, GZipCompressor buffers).
    // For the OOM handling we may already be limited in memory.
    // Lets ensure we have at least 20MB per thread.
    physical_memory_size_type free_memory = 0;
    // Return value ignored - defaulting to 0 on failure.
    (void)os::free_memory(free_memory);
    julong max_threads = free_memory / (20 * M);
    if (num_dump_threads > max_threads) {
      num_dump_threads = MAX2<uint>(1, (uint)max_threads);
    }
  }

  // create JFR event
  EventHeapDump event;

  AbstractCompressor* compressor = nullptr;

  if (compression > 0) {
    compressor = new (std::nothrow) GZipCompressor(compression);

    if (compressor == nullptr) {
      set_error("Could not allocate gzip compressor");
      return -1;
    }
  }

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 0 ns
profiling true true 0 ns

Event fields with their types and descriptions
Field Type Description
destination string Destination Path of the Dump
size long Size
gcBeforeDump boolean GC Before Dump
onOutOfMemoryError boolean Heap Dump on Out of Memory Error
overwrite boolean 21+ Overwrite Heap dump overwrites previous file location if it exists
compression int 21+ Compression Level Compression level of the dump, if larger than 0 we use gzip compression with this level

Examples 3
Example event data values and properties
compression int
-1
destination string
/tmp/jfr_sample_heap_566482200317.hprof
gcBeforeDump boolean
true
onOutOfMemoryError boolean
false
overwrite boolean
false
size long
14298384
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/String;Z)V
hidden boolean
false
modifiers int
258
name string
dumpHeap0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
com/sun/management/internal/HotSpotDiagnostic
package Package
exported boolean
false
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.management
name string
jdk.management
version string
25.0.4.1
name string
com/sun/management/internal
type FrameType
Native
…
truncated boolean
false
startTime long: millis
1017913893
Example event data values and properties
compression int
-1
destination string
/tmp/jfr_sample_heap_690776453202.hprof
gcBeforeDump boolean
true
onOutOfMemoryError boolean
false
overwrite boolean
false
size long
15622345
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/String;Z)V
hidden boolean
false
modifiers int
258
name string
dumpHeap0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
com/sun/management/internal/HotSpotDiagnostic
package Package
exported boolean
false
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.management
name string
jdk.management
version string
25.0.4.1
name string
com/sun/management/internal
type FrameType
Native
…
truncated boolean
false
startTime long: millis
1451810903
Example event data values and properties
compression int
-1
destination string
/tmp/jfr_sample_heap_2178218860663.hprof
gcBeforeDump boolean
true
onOutOfMemoryError boolean
false
overwrite boolean
false
size long
14980768
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/String;Z)V
hidden boolean
false
modifiers int
258
name string
dumpHeap0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
com/sun/management/internal/HotSpotDiagnostic
package Package
exported boolean
false
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.management
name string
jdk.management
version string
25.0.4.1
name string
com/sun/management/internal
type FrameType
Native
…
truncated boolean
false
startTime long: millis
1427293221

JavaAgent

default profiling startTime end of every chunk 21 25 27 28

Category: Java Virtual Machine / Diagnostics

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

A Java programming language agent making use of the java.lang.instrument package for instrumenting programs running on the JVM

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  event.set_options(agent->options());
  event.set_dynamic(agent->is_dynamic());
  event.set_initializationTime(agent->initialization_time());
  event.set_initializationDuration(agent->initialization_duration());
  event.commit();
}

TRACE_REQUEST_FUNC(JavaAgent) {
  JvmtiAgentList::Iterator it = JvmtiAgentList::java_agents();
  Ticks ticks = timestamp();
  while (it.has_next()) {
    const JvmtiAgent* agent = it.next();
    assert(agent->is_jplis(), "invariant");
    EventJavaAgent event;
    send_agent_event(event, agent, ticks);
  }
}

static void send_native_agent_events(JvmtiAgentList::Iterator& it, Ticks& timestamp) {
  while (it.has_next()) {
    const JvmtiAgent* agent = it.next();
    assert(!agent->is_jplis(), "invariant");
    EventNativeAgent event;
    event.set_path(agent->os_lib_path());
    send_agent_event(event, agent, timestamp);

Event configuration settings across JFR profiles
Configuration enabled period
default true endChunk
profiling true endChunk

Event fields with their types and descriptions
Field Type Description
name string Name
options string Options
dynamic boolean Dynamic If the agent attached to the JVM dynamically during runtime, i.e. not at startup
initializationTime Ticks Initialization Time The time the JVM initialized the agent
initializationDuration Tickspan Initialization Duration The duration of executing the initialization method, either premain or agentmain

Examples 3
Example event data values and properties
dynamic boolean
true
initializationDuration Tickspan
2634430
initializationTime Ticks
555050476
name string
/tmp/jfr_agent15005275580992799933.jar
options string
null
startTime long: millis
23186427134
Example event data values and properties
dynamic boolean
true
initializationDuration Tickspan
2694249
initializationTime Ticks
520146307
name string
/tmp/jfr_agent11192834965018173758.jar
options string
null
startTime long: millis
25404587438
Example event data values and properties
dynamic boolean
true
initializationDuration Tickspan
2079534
initializationTime Ticks
430729893
name string
/tmp/jfr_agent16064620304536894111.jar
options string
null
startTime long: millis
25323698140

NativeAgent

default profiling startTime end of every chunk 21 25 27 28

Category: Java Virtual Machine / Diagnostics

A native programming language agent making use of the JVMTI interface used by development, profiling and monitoring tools

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  Ticks ticks = timestamp();
  while (it.has_next()) {
    const JvmtiAgent* agent = it.next();
    assert(agent->is_jplis(), "invariant");
    EventJavaAgent event;
    send_agent_event(event, agent, ticks);
  }
}

static void send_native_agent_events(JvmtiAgentList::Iterator& it, Ticks& timestamp) {
  while (it.has_next()) {
    const JvmtiAgent* agent = it.next();
    assert(!agent->is_jplis(), "invariant");
    EventNativeAgent event;
    event.set_path(agent->os_lib_path());
    send_agent_event(event, agent, timestamp);
  }
}

TRACE_REQUEST_FUNC(NativeAgent) {
  Ticks ticks = timestamp();
  JvmtiAgentList::Iterator native_agents_it = JvmtiAgentList::native_agents();
  send_native_agent_events(native_agents_it, ticks);
  JvmtiAgentList::Iterator xrun_agents_it = JvmtiAgentList::xrun_agents();
  send_native_agent_events(xrun_agents_it, ticks);

Event configuration settings across JFR profiles
Configuration enabled period
default true endChunk
profiling true endChunk

Event fields with their types and descriptions
Field Type Description
name string Name
options string Options
dynamic boolean Dynamic If the library attached to the JVM dynamically during runtime, i.e. not at startup
initializationTime Ticks Initialization Time The time the JVM initialized the agent
initializationDuration Tickspan Initialization Duration The duration of executing the JVMTI VMInit event callback. If no VMInit callback is specified, the duration is 0. For a dynamically loaded agent, it is the duration of executing the call to Agent_OnAttach.
path string Path The path of the library

JVM: Flag

IntFlagChanged

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/flags/jvmFlagAccess.cpp:

  virtual void print_range(outputStream* st, const JVMFlagLimit* range) const {
    const JVMTypedFlagLimit<T>* r = (const JVMTypedFlagLimit<T>*)range;
    print_range_impl(st, r->min(), r->max());
  }

  virtual void range_error(const char* name, T value, T min, T max, bool verbose) const = 0;
  virtual void print_range_impl(outputStream* st, T min, T max) const = 0;
};

class FlagAccessImpl_int : public RangedFlagAccessImpl<int, EventIntFlagChanged> {
public:
  void range_error(const char* name, int value, int min, int max, bool verbose) const {
    JVMFlag::printError(verbose,
                        "int %s=%d is outside the allowed range "
                        "[ %d ... %d ]\n",
                        name, value, min, max);
  }
  JVMFlag::Error typed_check_constraint(void* func, int value, bool verbose) const {
    return ((JVMFlagConstraintFunc_int)func)(value, verbose);
  }
  void print_range_impl(outputStream* st, int min, int max) const {

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
name string Name
oldValue int Old Value
newValue int New Value
origin FlagValueOrigin Origin

Examples 3
Example event data values and properties
name string
HeapDumpGzipLevel
newValue int
0
oldValue int
1
origin FlagValueOrigin
Management
startTime long: millis
1402071509
Example event data values and properties
name string
HeapDumpGzipLevel
newValue int
1
oldValue int
0
origin FlagValueOrigin
Management
startTime long: millis
982256368
Example event data values and properties
name string
HeapDumpGzipLevel
newValue int
1
oldValue int
0
origin FlagValueOrigin
Management
startTime long: millis
1312184730

UnsignedIntFlagChanged

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/flags/jvmFlagAccess.cpp:

                        name, value, min, max);
  }
  JVMFlag::Error typed_check_constraint(void* func, int value, bool verbose) const {
    return ((JVMFlagConstraintFunc_int)func)(value, verbose);
  }
  void print_range_impl(outputStream* st, int min, int max) const {
    st->print("[ %-25d ... %25d ]", min, max);
  }
  void print_default_range(outputStream* st) const {
    st->print("[ " INT32_FORMAT_W(-25) " ... " INT32_FORMAT_W(25) " ]", INT_MIN, INT_MAX);
  }
};

class FlagAccessImpl_uint : public RangedFlagAccessImpl<uint, EventUnsignedIntFlagChanged> {
public:
  void range_error(const char* name, uint value, uint min, uint max, bool verbose) const {
    JVMFlag::printError(verbose,
                        "uint %s=%u is outside the allowed range "
                        "[ %u ... %u ]\n",
                        name, value, min, max);
  }
  JVMFlag::Error typed_check_constraint(void* func, uint value, bool verbose) const {
    return ((JVMFlagConstraintFunc_uint)func)(value, verbose);
  }
  void print_range_impl(outputStream* st, uint min, uint max) const {

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
name string Name
oldValue uint Old Value
newValue uint New Value
origin FlagValueOrigin Origin

Examples 3
Example event data values and properties
name string
FullGCHeapDumpLimit
newValue uint
1
oldValue uint
0
origin FlagValueOrigin
Management
startTime long: millis
1402099641
Example event data values and properties
name string
FullGCHeapDumpLimit
newValue uint
1
oldValue uint
0
origin FlagValueOrigin
Management
startTime long: millis
982280334
Example event data values and properties
name string
FullGCHeapDumpLimit
newValue uint
0
oldValue uint
1
origin FlagValueOrigin
Management
startTime long: millis
1312263478

LongFlagChanged

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/flags/jvmFlagAccess.cpp:

                        name, value, min, max);
  }
  JVMFlag::Error typed_check_constraint(void* func, uint value, bool verbose) const {
    return ((JVMFlagConstraintFunc_uint)func)(value, verbose);
  }
  void print_range_impl(outputStream* st, uint min, uint max) const {
    st->print("[ %-25u ... %25u ]", min, max);
  }
  void print_default_range(outputStream* st) const {
    st->print("[ " UINT32_FORMAT_W(-25) " ... " UINT32_FORMAT_W(25) " ]", 0, UINT_MAX);
  }
};

class FlagAccessImpl_intx : public RangedFlagAccessImpl<intx, EventLongFlagChanged> {
public:
  void range_error(const char* name, intx value, intx min, intx max, bool verbose) const {
    JVMFlag::printError(verbose,
                        "intx %s=%zd is outside the allowed range "
                        "[ %zd ... %zd ]\n",
                        name, value, min, max);
  }
  JVMFlag::Error typed_check_constraint(void* func, intx value, bool verbose) const {
    return ((JVMFlagConstraintFunc_intx)func)(value, verbose);
  }
  void print_range_impl(outputStream* st, intx min, intx max) const {

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
name string Name
oldValue long Old Value
newValue long New Value
origin FlagValueOrigin Origin

UnsignedLongFlagChanged

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/flags/jvmFlagAccess.cpp:

                        name, value, min, max);
  }
  JVMFlag::Error typed_check_constraint(void* func, intx value, bool verbose) const {
    return ((JVMFlagConstraintFunc_intx)func)(value, verbose);
  }
  void print_range_impl(outputStream* st, intx min, intx max) const {
    st->print("[ %-25zd ... %25zd ]", min, max);
  }
  void print_default_range(outputStream* st) const {
    st->print("[ %-25zd ... %25zd ]", min_intx, max_intx);
  }
};

class FlagAccessImpl_uintx : public RangedFlagAccessImpl<uintx, EventUnsignedLongFlagChanged> {
public:
  void range_error(const char* name, uintx value, uintx min, uintx max, bool verbose) const {
    JVMFlag::printError(verbose,
                        "uintx %s=%zu is outside the allowed range "
                        "[ %zu ... %zu ]\n",
                        name, value, min, max);
  }
  JVMFlag::Error typed_check_constraint(void* func, uintx value, bool verbose) const {
    return ((JVMFlagConstraintFunc_uintx)func)(value, verbose);
  }
  void print_range_impl(outputStream* st, uintx min, uintx max) const {
    st->print("[ %-25zu ... %25zu ]", min, max);
  }
  void print_default_range(outputStream* st) const {
    st->print("[ %-25zu ... %25zu ]", uintx(0), max_uintx);
  }
};

class FlagAccessImpl_uint64_t : public RangedFlagAccessImpl<uint64_t, EventUnsignedLongFlagChanged> {
public:
  void range_error(const char* name, uint64_t value, uint64_t min, uint64_t max, bool verbose) const {
    JVMFlag::printError(verbose,
                        "uint64_t %s=" UINT64_FORMAT " is outside the allowed range "
                        "[ " UINT64_FORMAT " ... " UINT64_FORMAT " ]\n",
                        name, value, min, max);
  }
  JVMFlag::Error typed_check_constraint(void* func, uint64_t value, bool verbose) const {
    return ((JVMFlagConstraintFunc_uint64_t)func)(value, verbose);
  }
  void print_range_impl(outputStream* st, uint64_t min, uint64_t max) const {
    st->print("[ " UINT64_FORMAT_W(-25) " ... " UINT64_FORMAT_W(25) " ]", min, max);
  }
  void print_default_range(outputStream* st) const {
    st->print("[ " UINT64_FORMAT_W(-25) " ... " UINT64_FORMAT_W(25) " ]", uint64_t(0), uint64_t(max_juint));
  }
};

class FlagAccessImpl_size_t : public RangedFlagAccessImpl<size_t, EventUnsignedLongFlagChanged> {
public:
  void range_error(const char* name, size_t value, size_t min, size_t max, bool verbose) const {
    JVMFlag::printError(verbose,
                        "size_t %s=%zu is outside the allowed range "
                        "[ %zu ... %zu ]\n",
                        name, value, min, max);
  }
  JVMFlag::Error typed_check_constraint(void* func, size_t value, bool verbose) const {
    return ((JVMFlagConstraintFunc_size_t)func)(value, verbose);
  }
  void print_range_impl(outputStream* st, size_t min, size_t max) const {

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
name string Name
oldValue ulong Old Value
newValue ulong New Value
origin FlagValueOrigin Origin

Examples 3
Example event data values and properties
name string
MaxHeapFreeRatio
newValue ulong
75
oldValue ulong
70
origin FlagValueOrigin
Management
startTime long: millis
1401823608
Example event data values and properties
name string
MinHeapFreeRatio
newValue ulong
45
oldValue ulong
0
origin FlagValueOrigin
Management
startTime long: millis
982059912
Example event data values and properties
name string
MaxHeapFreeRatio
newValue ulong
70
oldValue ulong
75
origin FlagValueOrigin
Management
startTime long: millis
1311996757

DoubleFlagChanged

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/flags/jvmFlagAccess.cpp:

                        name, value, min, max);
  }
  JVMFlag::Error typed_check_constraint(void* func, size_t value, bool verbose) const {
    return ((JVMFlagConstraintFunc_size_t)func)(value, verbose);
  }
  void print_range_impl(outputStream* st, size_t min, size_t max) const {
    st->print("[ %-25zu ... %25zu ]", min, max);
  }
  void print_default_range(outputStream* st) const {
    st->print("[ %-25zu ... %25zu ]", size_t(0), size_t(SIZE_MAX));
  }
};

class FlagAccessImpl_double : public RangedFlagAccessImpl<double, EventDoubleFlagChanged> {
public:
  void range_error(const char* name, double value, double min, double max, bool verbose) const {
    JVMFlag::printError(verbose,
                          "double %s=%f is outside the allowed range "
                          "[ %f ... %f ]\n",
                        name, value, min, max);
  }
  JVMFlag::Error typed_check_constraint(void* func, double value, bool verbose) const {
    return ((JVMFlagConstraintFunc_double)func)(value, verbose);
  }
  void print_range_impl(outputStream* st, double min, double max) const {

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
name string Name
oldValue double Old Value
newValue double New Value
origin FlagValueOrigin Origin

Examples 3
Example event data values and properties
name string
G1PeriodicGCSystemLoadThreshold
newValue double
0.5
oldValue double
0.0
origin FlagValueOrigin
Management
startTime long: millis
1401967225
Example event data values and properties
name string
G1PeriodicGCSystemLoadThreshold
newValue double
0.5
oldValue double
0.0
origin FlagValueOrigin
Management
startTime long: millis
982220514
Example event data values and properties
name string
G1PeriodicGCSystemLoadThreshold
newValue double
0.5
oldValue double
0.0
origin FlagValueOrigin
Management
startTime long: millis
1312118105

BooleanFlagChanged

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/flags/jvmFlagAccess.cpp:

    *((T*)value_addr) = old_value;
    flag->set_origin(origin);

    return JVMFlag::SUCCESS;
  }

  JVMFlag::Error check_constraint(const JVMFlag* flag, void * func, bool verbose) const  {
    return typed_check_constraint(func, flag->read<T>(), verbose);
  }

  virtual JVMFlag::Error typed_check_constraint(void * func, T value, bool verbose) const = 0;
};

class FlagAccessImpl_bool : public TypedFlagAccessImpl<bool, EventBooleanFlagChanged> {
public:
  JVMFlag::Error set_impl(JVMFlag* flag, void* value_addr, JVMFlagOrigin origin) const {
    bool verbose = JVMFlagLimit::verbose_checks_needed();
    return TypedFlagAccessImpl<bool, EventBooleanFlagChanged>
               ::check_constraint_and_set(flag, value_addr, origin, verbose);
  }

  JVMFlag::Error typed_check_constraint(void* func, bool value, bool verbose) const {
    return ((JVMFlagConstraintFunc_bool)func)(value, verbose);
  }
};

template <typename T, typename EVENT>
class RangedFlagAccessImpl : public TypedFlagAccessImpl<T, EVENT> {
public:

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
name string Name
oldValue boolean Old Value
newValue boolean New Value
origin FlagValueOrigin Origin

Examples 3
Example event data values and properties
name string
PrintConcurrentLocks
newValue boolean
false
oldValue boolean
true
origin FlagValueOrigin
Management
startTime long: millis
982019791
Example event data values and properties
name string
PrintConcurrentLocks
newValue boolean
true
oldValue boolean
false
origin FlagValueOrigin
Management
startTime long: millis
1401613658
Example event data values and properties
name string
PrintConcurrentLocks
newValue boolean
false
oldValue boolean
true
origin FlagValueOrigin
Management
startTime long: millis
1311830235

StringFlagChanged

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/flags/jvmFlagAccess.cpp:

  if (!flag->is_ccstr()) return JVMFlag::WRONG_FORMAT;
  const JVMTypedFlagLimit<ccstr>* constraint = (const JVMTypedFlagLimit<ccstr>*)JVMFlagLimit::get_constraint(flag);
  if (constraint != nullptr && constraint->phase() <= JVMFlagLimit::validating_phase()) {
    bool verbose = JVMFlagLimit::verbose_checks_needed() | (origin == JVMFlagOrigin::ERGONOMIC);
    JVMFlag::Error err = ((JVMFlagConstraintFunc_ccstr)constraint->constraint_func())(*value, verbose);
    if (err != JVMFlag::SUCCESS) {
      if (origin == JVMFlagOrigin::ERGONOMIC) {
        fatal("FLAG_SET_ERGO cannot be used to set an invalid value for %s", flag->name());
      }
      return err;
    }
  }
  ccstr old_value = flag->get_ccstr();
  trace_flag_changed<ccstr, EventStringFlagChanged>(flag, old_value, *value, origin);
  char* new_value = nullptr;
  if (*value != nullptr) {
    new_value = os::strdup_check_oom(*value);
  }
  flag->set_ccstr(new_value);
  if (!flag->is_default() && old_value != nullptr) {
    // Old value is heap allocated so free it.
    FREE_C_HEAP_ARRAY(old_value);
  }
  // Unlike the other APIs, the old value is NOT returned, so the caller won't need to free it.
  // The callers typically don't care what the old value is.

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
name string Name
oldValue string Old Value
newValue string New Value
origin FlagValueOrigin Origin

Examples 3
Example event data values and properties
name string
HeapDumpPath
newValue string
/tmp/jfr_heap
oldValue string
null
origin FlagValueOrigin
Management
startTime long: millis
982179352
Example event data values and properties
name string
HeapDumpPath
newValue string
/tmp/jfr_heap
oldValue string
null
origin FlagValueOrigin
Management
startTime long: millis
1312044006
Example event data values and properties
name string
HeapDumpPath
newValue string
/tmp/jfr_heap
oldValue string
null
origin FlagValueOrigin
Management
startTime long: millis
1401893799

IntFlag

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
name string Name
value int Value
origin FlagValueOrigin Origin

Examples 3
Example event data values and properties
name string
UseSSE
origin FlagValueOrigin
Default
startTime long: millis
457152258475
value int
4
Example event data values and properties
name string
AVX3Threshold
origin FlagValueOrigin
Default
startTime long: millis
8025077562
value int
4096
Example event data values and properties
name string
ParGCArrayScanChunk
origin FlagValueOrigin
Default
startTime long: millis
449445156573
value int
50

UnsignedIntFlag

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
name string Name
value uint Value
origin FlagValueOrigin Origin

Examples 3
Example event data values and properties
name string
G1RSetUpdatingPauseTimePercent
origin FlagValueOrigin
Default
startTime long: millis
454993849461
value uint
10
Example event data values and properties
name string
MarkSweepAlwaysCompactCount
origin FlagValueOrigin
Default
startTime long: millis
447754328603
value uint
4
Example event data values and properties
name string
G1HeapWastePercent
origin FlagValueOrigin
Default
startTime long: millis
8025100815
value uint
5

LongFlag

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
name string Name
value long Value
origin FlagValueOrigin Origin

Examples 3
Example event data values and properties
name string
Tier3DelayOn
origin FlagValueOrigin
Default
startTime long: millis
447754340250
value long
5
Example event data values and properties
name string
Tier3InvocationThreshold
origin FlagValueOrigin
Default
startTime long: millis
365021932
value long
200
Example event data values and properties
name string
NodeLimitFudgeFactor
origin FlagValueOrigin
Default
startTime long: millis
453049999998
value long
2000

UnsignedLongFlag

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
name string Name
value ulong Value
origin FlagValueOrigin Origin

Examples 3
Example event data values and properties
name string
MinMetaspaceExpansion
origin FlagValueOrigin
Default
startTime long: millis
447754364247
value ulong
327680
Example event data values and properties
name string
G1PeriodicGCInterval
origin FlagValueOrigin
Default
startTime long: millis
365040036
value ulong
0
Example event data values and properties
name string
NewSizeThreadIncrease
origin FlagValueOrigin
Default
startTime long: millis
453050047687
value ulong
5320

DoubleFlag

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
name string Name
value double Value
origin FlagValueOrigin Origin

Examples 3
Example event data values and properties
name string
SelfDestructTimer
origin FlagValueOrigin
Default
startTime long: millis
454119683388
value double
0.0
Example event data values and properties
name string
ZCollectionIntervalMajor
origin FlagValueOrigin
Default
startTime long: millis
464049027407
value double
-1.0
Example event data values and properties
name string
ZFragmentationLimit
origin FlagValueOrigin
Default
startTime long: millis
23251915057
value double
5.0

BooleanFlag

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
name string Name
value boolean Value
origin FlagValueOrigin Origin

Examples 3
Example event data values and properties
name string
UseFastSignatureHandlers
origin FlagValueOrigin
Default
startTime long: millis
447754433030
value boolean
true
Example event data values and properties
name string
PrintLIRWithAssembly
origin FlagValueOrigin
Default
startTime long: millis
365068149
value boolean
false
Example event data values and properties
name string
BailoutOnExceptionHandlers
origin FlagValueOrigin
Default
startTime long: millis
453050069318
value boolean
false

StringFlag

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrRedactedEvents.cpp:

         if (log && redacted) {
           log_debug(jfr, redact)("Redacted string flag '%s'", flag->name());
         }
         _string_flags->append(new StringFlag(flag, value));
      }
      ++flag;
    }
  }
  for (int i = 0; i < _string_flags->length(); i++) {
    StringFlag* sf = _string_flags->at(i);
    const JVMFlag* flag = sf->jvm_flag();
    EventStringFlag event;
    event.set_name(flag->name());
    if (sf->redacted_value() != nullptr) {
      // If a flag is redacted and later changed at runtime,
      // the event will still show the redacted text.
      event.set_value(sf->redacted_value());
    } else {
      // If a flag is not redacted the first time,
      // it will not be redacted later if it's changed at runtime.
      event.set_value(flag->get_ccstr());
    }
    event.set_origin(static_cast<u8>(flag->get_origin()));

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
name string Name
value string Value
origin FlagValueOrigin Origin

Examples 3
Example event data values and properties
name string
MallocTraceUnwindLibName
origin FlagValueOrigin
Default
startTime long: millis
453050152344
value string
libunwind.so.8
Example event data values and properties
name string
PerfDataSaveFile
origin FlagValueOrigin
Default
startTime long: millis
365144542
value string
null
Example event data values and properties
name string
ExtraSharedClassListFile
origin FlagValueOrigin
Default
startTime long: millis
447754449485
value string
null

JVM: GC: Collector

GarbageCollection

default profiling startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Collector

Garbage collection performed by the JVM

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

// All GC dependencies against the trace framework is contained within this file.

typedef uintptr_t TraceAddress;

bool GCTracer::should_send_cpu_time_event() const {
  return EventGCCPUTime::is_enabled();
}

void GCTracer::send_garbage_collection_event() const {
  EventGarbageCollection event(UNTIMED);
  if (event.should_commit()) {
    event.set_gcId(GCId::current());
    event.set_name(_shared_gc_info.name());
    event.set_cause((u2) _shared_gc_info.cause());
    event.set_sumOfPauses(_shared_gc_info.sum_of_pauses());
    event.set_longestPause(_shared_gc_info.longest_pause());
    event.set_starttime(_shared_gc_info.start_timestamp());
    event.set_endtime(_shared_gc_info.end_timestamp());
    event.commit();
  }
}

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
name GCName Name The name of the Garbage Collector
cause GCCause Cause The reason for triggering this Garbage Collection
sumOfPauses Tickspan Sum of Pauses Sum of all the times in which Java execution was paused during the garbage collection
longestPause Tickspan Longest Pause Longest individual pause during the garbage collection

Examples 3
Example event data values and properties
cause GCCause
G1 Humongous Allocation
gcId uint
1099
longestPause Tickspan
7877185
name GCName
G1New
startTime long: millis
462127906693
sumOfPauses Tickspan
7877185
Example event data values and properties
cause GCCause
Heap Inspection Initiated GC
gcId uint
341
longestPause Tickspan
270749183
name GCName
ParallelOld
startTime long: millis
450551909668
sumOfPauses Tickspan
270749183
Example event data values and properties
cause GCCause
System.gc()
gcId uint
65
longestPause Tickspan
22626998
name GCName
G1Full
startTime long: millis
1910407459
sumOfPauses Tickspan
22626998

SystemGC

default profiling startTime duration eventThread stackTrace 17 21 25 27 28

Category: Java Virtual Machine / GC / Collector

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/prims/jvm.cpp:

    event.commit();
  }
JVM_END


JVM_ENTRY_NO_ENV(void, JVM_Halt(jint code))
  before_exit(thread, true);
  vm_exit(code);
JVM_END


JVM_ENTRY_NO_ENV(void, JVM_GC(void))
  if (!DisableExplicitGC) {
    EventSystemGC event;
    event.set_invokedConcurrent(ExplicitGCInvokesConcurrent);
    Universe::heap()->collect(GCCause::_java_lang_system_gc);
    event.commit();
  }
JVM_END


JVM_LEAF(jlong, JVM_MaxObjectInspectionAge(void))
  return Universe::heap()->millis_since_last_whole_heap_examined();
JVM_END

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 0 ms
profiling true true 0 ms

Event fields with their types and descriptions
Field Type Description
invokedConcurrent boolean Invoked Concurrent

Examples 3
Example event data values and properties
invokedConcurrent boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
257
name string
gc
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Runtime
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
2990533549
Example event data values and properties
invokedConcurrent boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
257
name string
gc
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Runtime
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
475284043262
Example event data values and properties
invokedConcurrent boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
257
name string
gc
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Runtime
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
485458450203

ParallelOldGarbageCollection

default profiling startTime duration 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Collector

Appearing in: linux_ParallelGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Extra information specific to Parallel Old Garbage Collections

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

    e.set_smallChunksTotalSize(summary.small_chunks_size_in_bytes());

    e.set_mediumChunks(summary.num_medium_chunks());
    e.set_mediumChunksTotalSize(summary.medium_chunks_size_in_bytes());

    e.set_humongousChunks(summary.num_humongous_chunks());
    e.set_humongousChunksTotalSize(summary.humongous_chunks_size_in_bytes());

    e.commit();
  }
}

void ParallelOldTracer::send_parallel_old_event() const {
  EventParallelOldGarbageCollection e(UNTIMED);
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_densePrefix((TraceAddress)_parallel_old_gc_info.dense_prefix());
    e.set_starttime(_shared_gc_info.start_timestamp());
    e.set_endtime(_shared_gc_info.end_timestamp());
    e.commit();
  }
}

void YoungGCTracer::send_young_gc_event() const {
  EventYoungGarbageCollection e(UNTIMED);

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
densePrefix ulong: address Dense Prefix The address of the dense prefix, used when compacting

Examples 2
Example event data values and properties
densePrefix ulong: address
30423908352
gcId uint
349
startTime long: millis
459231814375
Example event data values and properties
densePrefix ulong: address
30173822976
gcId uint
30
startTime long: millis
1378158575

YoungGarbageCollection

default profiling startTime duration 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Collector

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

Extra information specific to Young Garbage Collections

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

void ParallelOldTracer::send_parallel_old_event() const {
  EventParallelOldGarbageCollection e(UNTIMED);
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_densePrefix((TraceAddress)_parallel_old_gc_info.dense_prefix());
    e.set_starttime(_shared_gc_info.start_timestamp());
    e.set_endtime(_shared_gc_info.end_timestamp());
    e.commit();
  }
}

void YoungGCTracer::send_young_gc_event() const {
  EventYoungGarbageCollection e(UNTIMED);
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_tenuringThreshold(_tenuring_threshold);
    e.set_starttime(_shared_gc_info.start_timestamp());
    e.set_endtime(_shared_gc_info.end_timestamp());
    e.commit();
  }
}

bool YoungGCTracer::should_send_promotion_in_new_plab_event() const {
  return EventPromoteObjectInNewPLAB::is_enabled();

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
tenuringThreshold uint Tenuring Threshold

Examples 3
Example event data values and properties
gcId uint
1167
startTime long: millis
481694804596
tenuringThreshold uint
15
Example event data values and properties
gcId uint
360
startTime long: millis
476310899128
tenuringThreshold uint
1
Example event data values and properties
gcId uint
5
startTime long: millis
574870718
tenuringThreshold uint
2

OldGarbageCollection

default profiling startTime duration 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Collector

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

Extra information specific to Old Garbage Collections

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

  EventPromoteObjectOutsidePLAB event;
  if (event.should_commit()) {
    event.set_gcId(GCId::current());
    event.set_objectClass(klass);
    event.set_objectSize(obj_size);
    event.set_tenured(tenured);
    event.set_tenuringAge(age);
    event.commit();
  }
}

void OldGCTracer::send_old_gc_event() const {
  EventOldGarbageCollection e(UNTIMED);
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_starttime(_shared_gc_info.start_timestamp());
    e.set_endtime(_shared_gc_info.end_timestamp());
    e.commit();
  }
}

static JfrStructCopyFailed to_struct(const CopyFailedInfo& cf_info) {
  JfrStructCopyFailed failed_info;
  failed_info.set_objectCount(cf_info.failed_count());

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier

Examples 3
Example event data values and properties
gcId uint
1176
startTime long: millis
490412816945
Example event data values and properties
gcId uint
22
startTime long: millis
1312956938
Example event data values and properties
gcId uint
373
startTime long: millis
489902538674

G1GarbageCollection

default profiling startTime duration 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Collector

Appearing in: graalvm_linux_G1GC, linux_G1GC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Extra information specific to G1 Young Garbage Collections

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/g1/g1Trace.cpp:

                                additional_buffer_size,
                                non_humongous_allocation,
                                peak_extra_humongous_occupancy,
                                predicted_old_non_hum_alloc_rate,
                                predicted_peak_extra_humongous_occupancy,
                                predicted_marking_length,
                                prediction_active);
}

void G1NewTracer::send_g1_young_gc_event() {
  // Check that the pause type has been updated to something valid for this event.
  G1CollectorState::assert_is_young_pause(_pause);

  EventG1GarbageCollection e(UNTIMED);
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_type(static_cast<uint>(_pause));
    e.set_starttime(_shared_gc_info.start_timestamp());
    e.set_endtime(_shared_gc_info.end_timestamp());
    e.commit();
  }
}

void G1NewTracer::send_evacuation_info_event(G1EvacInfo* info) {
  EventEvacuationInformation e;

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
type G1YCType Type

Examples 3
Example event data values and properties
gcId uint
1233
startTime long: millis
491804472255
type G1YCType
Prepare Mixed
Example event data values and properties
gcId uint
12
startTime long: millis
744243601
type G1YCType
Normal
Example event data values and properties
gcId uint
1149
startTime long: millis
475777403410
type G1YCType
Concurrent Start

ZYoungGarbageCollection

default profiling startTime duration eventThread 21 25 27 28

Category: Java Virtual Machine / GC / Collector

Appearing in: linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Extra information specific to ZGC Young Garbage Collections

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/z/zTracer.cpp:

ZMinorTracer::ZMinorTracer()
  : GCTracer(ZMinor) {}

ZMajorTracer::ZMajorTracer()
  : GCTracer(ZMajor) {}

void ZGenerationTracer::report_start(const Ticks& timestamp) {
  _start = timestamp;
}

void ZYoungTracer::report_end(const Ticks& timestamp) {
  NoSafepointVerifier nsv;

  EventZYoungGarbageCollection e(UNTIMED);
  e.set_gcId(GCId::current());
  e.set_tenuringThreshold(ZGeneration::young()->tenuring_threshold());
  e.set_starttime(_start);
  e.set_endtime(timestamp);
  e.commit();
}

void ZOldTracer::report_end(const Ticks& timestamp) {
  NoSafepointVerifier nsv;

  EventZOldGarbageCollection e(UNTIMED);

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
tenuringThreshold uint Tenuring Threshold

Examples 2
Example event data values and properties
gcId uint
20
startTime long: millis
2146316033
tenuringThreshold uint
0
Example event data values and properties
gcId uint
273
startTime long: millis
666430238553
tenuringThreshold uint
3

ZOldGarbageCollection

default profiling startTime duration eventThread 21 25 27 28

Category: Java Virtual Machine / GC / Collector

Appearing in: linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Extra information specific to ZGC Old Garbage Collections

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/z/zTracer.cpp:

  NoSafepointVerifier nsv;

  EventZYoungGarbageCollection e(UNTIMED);
  e.set_gcId(GCId::current());
  e.set_tenuringThreshold(ZGeneration::young()->tenuring_threshold());
  e.set_starttime(_start);
  e.set_endtime(timestamp);
  e.commit();
}

void ZOldTracer::report_end(const Ticks& timestamp) {
  NoSafepointVerifier nsv;

  EventZOldGarbageCollection e(UNTIMED);
  e.set_gcId(GCId::current());
  e.set_starttime(_start);
  e.set_endtime(timestamp);
  e.commit();
}

void ZTracer::initialize() {
  JFR_ONLY(register_jfr_type_serializers();)
}

void ZTracer::send_stat_counter(const ZStatCounter& counter, uint64_t increment, uint64_t value) {

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier

Examples 2
Example event data values and properties
gcId uint
82
startTime long: millis
3894721625
Example event data values and properties
gcId uint
286
startTime long: millis
678255969085

JVM: GC: Configuration

GCConfiguration

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Configuration

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

The configuration of the garbage collector

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

TRACE_REQUEST_FUNC(G1HeapRegionInformation) {
  G1GC_ONLY(G1HeapRegionEventSender::send_events());
}

// Java Mission Control (JMC) uses (Java) Long.MIN_VALUE to describe that a
// long value is undefined.
static jlong jmc_undefined_long = min_jlong;

TRACE_REQUEST_FUNC(GCConfiguration) {
  GCConfiguration conf;
  jlong pause_target = conf.has_pause_target_default_value() ? jmc_undefined_long : conf.pause_target();
  EventGCConfiguration event;
  event.set_youngCollector(conf.young_collector());
  event.set_oldCollector(conf.old_collector());
  event.set_parallelGCThreads(conf.num_parallel_gc_threads());
  event.set_concurrentGCThreads(conf.num_concurrent_gc_threads());
  event.set_usesDynamicGCThreads(conf.uses_dynamic_gc_threads());
  event.set_isExplicitGCConcurrent(conf.is_explicit_gc_concurrent());
  event.set_isExplicitGCDisabled(conf.is_explicit_gc_disabled());
  event.set_gcTimeRatio(static_cast<unsigned int>(conf.gc_time_ratio()));
  event.set_pauseTarget((s8)pause_target);
  event.commit();
}

Event configuration settings across JFR profiles
Configuration enabled period
default true everyChunk
profiling true everyChunk

Event fields with their types and descriptions
Field Type Description
youngCollector GCName Young Garbage Collector The garbage collector used for the young generation
oldCollector GCName Old Garbage Collector The garbage collector used for the old generation
parallelGCThreads uint Parallel GC Threads Number of parallel threads to use for garbage collection
concurrentGCThreads uint Concurrent GC Threads Number of concurrent threads to use for garbage collection
usesDynamicGCThreads boolean Uses Dynamic GC Threads Whether a dynamic number of GC threads are used or not
isExplicitGCConcurrent boolean Concurrent Explicit GC Whether System.gc() is concurrent or not
isExplicitGCDisabled boolean Disabled Explicit GC Whether System.gc() will cause a garbage collection or not
pauseTarget long: millis Pause Target Target for GC pauses
gcTimeRatio uint GC Time Ratio Target for runtime vs garbage collection time

Examples 3
Example event data values and properties
concurrentGCThreads uint
0
gcTimeRatio uint
99
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
ParallelOld
parallelGCThreads uint
4
pauseTarget long: millis
-9223372036854775808
startTime long: millis
447960954952
usesDynamicGCThreads boolean
true
youngCollector GCName
ParallelScavenge
Example event data values and properties
concurrentGCThreads uint
1
gcTimeRatio uint
12
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
G1Old
parallelGCThreads uint
4
pauseTarget long: millis
-9223372036854775808
startTime long: millis
459248409535
usesDynamicGCThreads boolean
true
youngCollector GCName
G1New
Example event data values and properties
concurrentGCThreads uint
1
gcTimeRatio uint
12
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
G1Old
parallelGCThreads uint
4
pauseTarget long: millis
-9223372036854775808
startTime long: millis
375559512
usesDynamicGCThreads boolean
true
youngCollector GCName
G1New

GCSurvivorConfiguration

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Configuration

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

The configuration of the survivors of garbage collection

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

TRACE_REQUEST_FUNC(GCTLABConfiguration) {
  GCTLABConfiguration conf;
  EventGCTLABConfiguration event;
  event.set_usesTLABs(conf.uses_tlabs());
  event.set_minTLABSize(conf.min_tlab_size());
  event.set_tlabRefillWasteLimit(conf.tlab_refill_waste_limit());
  event.commit();
}

TRACE_REQUEST_FUNC(GCSurvivorConfiguration) {
  GCSurvivorConfiguration conf;
  EventGCSurvivorConfiguration event;
  event.set_maxTenuringThreshold(static_cast<u1>(conf.max_tenuring_threshold()));
  event.set_initialTenuringThreshold(static_cast<u1>(conf.initial_tenuring_threshold()));
  event.commit();
}

TRACE_REQUEST_FUNC(GCHeapConfiguration) {
  GCHeapConfiguration conf;
  EventGCHeapConfiguration event;
  event.set_minSize(conf.min_size());
  event.set_maxSize(conf.max_size());
  event.set_initialSize(conf.initial_size());

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
maxTenuringThreshold ubyte Maximum Tenuring Threshold Upper limit for the age of how old objects to keep in the survivor area
initialTenuringThreshold ubyte Initial Tenuring Threshold Initial age limit for how old objects to keep in survivor area

Examples 3
Example event data values and properties
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
464264412374
Example event data values and properties
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
449656104355
Example event data values and properties
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
15645411058

GCTLABConfiguration

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Configuration

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

The configuration of the Thread Local Allocation Buffers (TLABs)

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  event.set_oldCollector(conf.old_collector());
  event.set_parallelGCThreads(conf.num_parallel_gc_threads());
  event.set_concurrentGCThreads(conf.num_concurrent_gc_threads());
  event.set_usesDynamicGCThreads(conf.uses_dynamic_gc_threads());
  event.set_isExplicitGCConcurrent(conf.is_explicit_gc_concurrent());
  event.set_isExplicitGCDisabled(conf.is_explicit_gc_disabled());
  event.set_gcTimeRatio(static_cast<unsigned int>(conf.gc_time_ratio()));
  event.set_pauseTarget((s8)pause_target);
  event.commit();
}

TRACE_REQUEST_FUNC(GCTLABConfiguration) {
  GCTLABConfiguration conf;
  EventGCTLABConfiguration event;
  event.set_usesTLABs(conf.uses_tlabs());
  event.set_minTLABSize(conf.min_tlab_size());
  event.set_tlabRefillWasteLimit(conf.tlab_refill_waste_limit());
  event.commit();
}

TRACE_REQUEST_FUNC(GCSurvivorConfiguration) {
  GCSurvivorConfiguration conf;
  EventGCSurvivorConfiguration event;
  event.set_maxTenuringThreshold(static_cast<u1>(conf.max_tenuring_threshold()));
  event.set_initialTenuringThreshold(static_cast<u1>(conf.initial_tenuring_threshold()));

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
usesTLABs boolean TLABs Used If Thread Local Allocation Buffers (TLABs) are in use
minTLABSize ulong: bytes Minimum TLAB Size
tlabRefillWasteLimit ulong: bytes TLAB Refill Waste Limit

Examples 3
Example event data values and properties
minTLABSize ulong: bytes
2048
startTime long: millis
487626807791
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
Example event data values and properties
minTLABSize ulong: bytes
2048
startTime long: millis
457363577003
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
Example event data values and properties
minTLABSize ulong: bytes
2048
startTime long: millis
375563028
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true

GCHeapConfiguration

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Configuration

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

The configuration of the garbage collected heap

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  event.commit();
}

TRACE_REQUEST_FUNC(GCSurvivorConfiguration) {
  GCSurvivorConfiguration conf;
  EventGCSurvivorConfiguration event;
  event.set_maxTenuringThreshold(static_cast<u1>(conf.max_tenuring_threshold()));
  event.set_initialTenuringThreshold(static_cast<u1>(conf.initial_tenuring_threshold()));
  event.commit();
}

TRACE_REQUEST_FUNC(GCHeapConfiguration) {
  GCHeapConfiguration conf;
  EventGCHeapConfiguration event;
  event.set_minSize(conf.min_size());
  event.set_maxSize(conf.max_size());
  event.set_initialSize(conf.initial_size());
  event.set_usesCompressedOops(conf.uses_compressed_oops());
  event.set_compressedOopsMode(conf.narrow_oop_mode());
  event.set_objectAlignment(conf.object_alignment_in_bytes());
  event.set_heapAddressBits(static_cast<u1>(conf.heap_address_size_in_bits()));
  event.commit();
}

TRACE_REQUEST_FUNC(YoungGenerationConfiguration) {

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
minSize ulong: bytes Minimum Heap Size
maxSize ulong: bytes Maximum Heap Size
initialSize ulong: bytes Initial Heap Size
usesCompressedOops boolean If Compressed Oops Are Used If compressed Oops (Ordinary Object Pointers) are enabled
compressedOopsMode NarrowOopMode Compressed Oops Mode The kind of compressed oops being used
objectAlignment ulong: bytes Object Alignment Object alignment (in bytes) on the heap
heapAddressBits ubyte Heap Address Size Heap Address Size (in bits)

Examples 3
Example event data values and properties
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
262144000
maxSize ulong: bytes
4192206848
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
455797549797
usesCompressedOops boolean
true
Example event data values and properties
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
262144000
maxSize ulong: bytes
4192206848
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
497004697505
usesCompressedOops boolean
true
Example event data values and properties
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
262144000
maxSize ulong: bytes
4192206848
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
375564080
usesCompressedOops boolean
true

YoungGenerationConfiguration

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Configuration

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

The configuration of the young generation of the garbage collected heap

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  event.set_minSize(conf.min_size());
  event.set_maxSize(conf.max_size());
  event.set_initialSize(conf.initial_size());
  event.set_usesCompressedOops(conf.uses_compressed_oops());
  event.set_compressedOopsMode(conf.narrow_oop_mode());
  event.set_objectAlignment(conf.object_alignment_in_bytes());
  event.set_heapAddressBits(static_cast<u1>(conf.heap_address_size_in_bits()));
  event.commit();
}

TRACE_REQUEST_FUNC(YoungGenerationConfiguration) {
  GCYoungGenerationConfiguration conf;
  jlong max_size = conf.has_max_size_default_value() ? jmc_undefined_long : conf.max_size();
  EventYoungGenerationConfiguration event;
  event.set_maxSize((u8)max_size);
  event.set_minSize(conf.min_size());
  event.set_newRatio(static_cast<unsigned int>(conf.new_ratio()));
  event.commit();
}

TRACE_REQUEST_FUNC(InitialSystemProperty) {
  JfrRedactedEvents::emit_initial_system_properties();
}

TRACE_REQUEST_FUNC(ThreadAllocationStatistics) {

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
minSize ulong: bytes Minimum Young Generation Size
maxSize ulong: bytes Maximum Young Generation Size
newRatio uint New Ratio The size of the young generation relative to the tenured generation

Examples 3
Example event data values and properties
maxSize ulong: bytes
2514485248
minSize ulong: bytes
1363144
newRatio uint
2
startTime long: millis
467380663828
Example event data values and properties
maxSize ulong: bytes
2514485248
minSize ulong: bytes
1363144
newRatio uint
2
startTime long: millis
23271500440
Example event data values and properties
maxSize ulong: bytes
1396703232
minSize ulong: bytes
85983232
newRatio uint
2
startTime long: millis
481011652408

JVM: GC: Detailed

ZThreadDebug

internal startTime duration eventThread 18 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Temporary latency measurements used during development and debugging of ZGC

Only valid for the ZGC.

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/z/zTracer.cpp:

  NoSafepointVerifier nsv;

  EventZThreadPhase e(UNTIMED);
  if (e.should_commit()) {
    e.set_gcId(GCId::current_or_undefined());
    e.set_name(name);
    e.set_starttime(start);
    e.set_endtime(end);
    e.commit();
  }
}

void ZTracer::send_thread_debug(const char* name, const Ticks& start, const Ticks& end) {
  NoSafepointVerifier nsv;

  EventZThreadDebug e(UNTIMED);
  if (e.should_commit()) {
    e.set_gcId(GCId::current_or_undefined());
    e.set_name(name);
    e.set_starttime(start);
    e.set_endtime(end);
    e.commit();
  }
}

src/hotspot/share/gc/z/zTracer.inline.hpp:

inline void ZTracer::report_stat_sampler(const ZStatSampler& sampler, uint64_t value) {
  if (EventZStatisticsSampler::is_enabled()) {
    send_stat_sampler(sampler, value);
  }
}

inline void ZTracer::report_thread_phase(const char* name, const Ticks& start, const Ticks& end) {
  if (EventZThreadPhase::is_enabled()) {
    send_thread_phase(name, start, end);
  }
}

inline void ZTracer::report_thread_debug(const char* name, const Ticks& start, const Ticks& end) {
  if (EventZThreadDebug::is_enabled()) {
    send_thread_debug(name, start, end);
  }
}

inline ZTraceThreadDebug::ZTraceThreadDebug(const char* name)
  : _start(Ticks::now()),
    _name(name) {}

inline ZTraceThreadDebug::~ZTraceThreadDebug() {
  ZTracer::report_thread_debug(_name, _start, Ticks::now());
}

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
name string Name The name of the GC runner

G1MMU

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/g1/g1Trace.cpp:

void G1OldTracer::report_gc_start_impl(GCCause::Cause cause, const Ticks& timestamp) {
  _shared_gc_info.set_start_timestamp(timestamp);
}

void G1OldTracer::set_gc_cause(GCCause::Cause cause) {
  _shared_gc_info.set_cause(cause);
}

void G1MMUTracer::report_mmu(double time_slice_sec, double gc_time_sec, double max_time_sec) {
  send_g1_mmu_event(time_slice_sec * MILLIUNITS,
                    gc_time_sec * MILLIUNITS,
                    max_time_sec * MILLIUNITS);
}

void G1MMUTracer::send_g1_mmu_event(double time_slice_ms, double gc_time_ms, double max_time_ms) {
  EventG1MMU e;
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_timeSlice(time_slice_ms);
    e.set_gcTime(gc_time_ms);
    e.set_pauseTarget(max_time_ms);
    e.commit();
  }
}

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
timeSlice long: millis Time Slice Time slice used to calculate MMU
gcTime long: millis GC Time Time stopped because of GC during last time slice
pauseTarget long: millis Pause Target Max time allowed to be spent on GC during last time slice

Examples 3
Example event data values and properties
gcId uint
1170
gcTime long: millis
8
pauseTarget long: millis
200
startTime long: millis
483938393438
timeSlice long: millis
201
Example event data values and properties
gcId uint
1228
gcTime long: millis
5
pauseTarget long: millis
200
startTime long: millis
490646274366
timeSlice long: millis
201
Example event data values and properties
gcId uint
173
gcTime long: millis
6
pauseTarget long: millis
200
startTime long: millis
3217503449
timeSlice long: millis
201

EvacuationInformation

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/g1/g1Trace.cpp:

  G1CollectorState::assert_is_young_pause(_pause);

  EventG1GarbageCollection e(UNTIMED);
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_type(static_cast<uint>(_pause));
    e.set_starttime(_shared_gc_info.start_timestamp());
    e.set_endtime(_shared_gc_info.end_timestamp());
    e.commit();
  }
}

void G1NewTracer::send_evacuation_info_event(G1EvacInfo* info) {
  EventEvacuationInformation e;
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_cSetRegions(info->collection_set_regions());
    e.set_cSetUsedBefore(info->collection_set_used_before());
    e.set_cSetUsedAfter(info->collection_set_used_after());
    e.set_allocationRegions(info->allocation_regions());
    e.set_allocationRegionsUsedBefore(info->alloc_regions_used_before());
    e.set_allocationRegionsUsedAfter(info->alloc_regions_used_before() + info->bytes_used());
    e.set_bytesCopied(info->bytes_used());
    e.set_regionsFreed(info->regions_freed());
    e.commit();

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
cSetRegions uint Collection Set Regions
cSetUsedBefore ulong: bytes Collection Set Before Memory usage before GC in the collection set regions
cSetUsedAfter ulong: bytes Collection Set After Memory usage after GC in the collection set regions
allocationRegions uint Allocation Regions Regions chosen as allocation regions during evacuation (includes survivors and old space regions)
allocationRegionsUsedBefore ulong: bytes Allocation Regions Before Memory usage before GC in allocation regions
allocationRegionsUsedAfter ulong: bytes Allocation Regions After Memory usage after GC in allocation regions
bytesCopied ulong: bytes Bytes Copied
regionsFreed uint Regions Freed

Examples 3
Example event data values and properties
allocationRegions uint
2
allocationRegionsUsedAfter ulong: bytes
2098064
allocationRegionsUsedBefore ulong: bytes
976592
bytesCopied ulong: bytes
1121472
cSetRegions uint
4
cSetUsedAfter ulong: bytes
0
cSetUsedBefore ulong: bytes
8388608
gcId uint
166
regionsFreed uint
4
startTime long: millis
3129027178
Example event data values and properties
allocationRegions uint
1
allocationRegionsUsedAfter ulong: bytes
1063248
allocationRegionsUsedBefore ulong: bytes
0
bytesCopied ulong: bytes
1063248
cSetRegions uint
11
cSetUsedAfter ulong: bytes
0
cSetUsedBefore ulong: bytes
23068672
gcId uint
1117
regionsFreed uint
11
startTime long: millis
467153731249
Example event data values and properties
allocationRegions uint
1
allocationRegionsUsedAfter ulong: bytes
57184
allocationRegionsUsedBefore ulong: bytes
0
bytesCopied ulong: bytes
57184
cSetRegions uint
5
cSetUsedAfter ulong: bytes
0
cSetUsedBefore ulong: bytes
8518256
gcId uint
1199
regionsFreed uint
5
startTime long: millis
483794403332

ObjectCountAfterGC

startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/objectCountEventSender.cpp:

#if INCLUDE_SERVICES

bool ObjectCountEventSender::should_send_event() {
#if INCLUDE_JFR
  return _should_send_requestable_event || EventObjectCountAfterGC::is_enabled();
#else
  return false;
#endif // INCLUDE_JFR
}

bool ObjectCountEventSender::_should_send_requestable_event = false;

void ObjectCountEventSender::enable_requestable_event() {
  _should_send_requestable_event = true;
}

void ObjectCountEventSender::disable_requestable_event() {

src/hotspot/share/gc/shared/objectCountEventSender.cpp:

template <typename T>
void ObjectCountEventSender::send_event_if_enabled(Klass* klass, jlong count, julong size, const Ticks& timestamp) {
  T event(UNTIMED);
  if (event.should_commit()) {
    event.set_starttime(timestamp);
    event.set_endtime(timestamp);
    event.set_gcId(GCId::current());
    event.set_objectClass(klass);
    event.set_count(count);
    event.set_totalSize(size);
    event.commit();
  }
}

void ObjectCountEventSender::send(const KlassInfoEntry* entry, const Ticks& timestamp) {
  Klass* klass = entry->klass();
  jlong count = entry->count();
  julong total_size = entry->words() * BytesPerWord;

  send_event_if_enabled<EventObjectCount>(klass, count, total_size, timestamp);
  send_event_if_enabled<EventObjectCountAfterGC>(klass, count, total_size, timestamp);
}

#endif // INCLUDE_SERVICES

Event configuration settings across JFR profiles
Configuration enabled
default false
profiling false

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
objectClass Class Object Class
count long Count
totalSize ulong: bytes Total Size

Examples 3
Example event data values and properties
count long
83964
gcId uint
341
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
16
name string
java/lang/invoke/MemberName
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang/invoke
startTime long: millis
450754001835
totalSize ulong: bytes
3358560
Example event data values and properties
count long
468211
gcId uint
1072
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/String
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
startTime long: millis
454808271708
totalSize ulong: bytes
11237064
Example event data values and properties
count long
2435
gcId uint
0
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
24
name string
java/util/ImmutableCollections$List12
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
startTime long: millis
370566773
totalSize ulong: bytes
38960

G1EvacuationYoungStatistics

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Memory related evacuation statistics during GC for the young generation

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/g1/g1Trace.cpp:

  s.set_allocated(summary.allocated() * HeapWordSize);
  s.set_wasted(summary.wasted() * HeapWordSize);
  s.set_used(summary.used() * HeapWordSize);
  s.set_undoWaste(summary.undo_wasted() * HeapWordSize);
  s.set_regionEndWaste(summary.region_end_waste() * HeapWordSize);
  s.set_regionsRefilled(summary.regions_filled());
  s.set_directAllocated(summary.direct_allocated() * HeapWordSize);
  s.set_failureUsed(summary.failure_used() * HeapWordSize);
  s.set_failureWaste(summary.failure_waste() * HeapWordSize);
  return s;
}

void G1NewTracer::send_young_evacuation_statistics(const G1EvacSummary& summary) const {
  EventG1EvacuationYoungStatistics surv_evt;
  if (surv_evt.should_commit()) {
    surv_evt.set_statistics(create_g1_evacstats(GCId::current(), summary));
    surv_evt.commit();
  }
}

void G1NewTracer::send_old_evacuation_statistics(const G1EvacSummary& summary) const {
  EventG1EvacuationOldStatistics old_evt;
  if (old_evt.should_commit()) {
    old_evt.set_statistics(create_g1_evacstats(GCId::current(), summary));
    old_evt.commit();

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
statistics G1EvacuationStatistics struct Evacuation Statistics

Examples 3
Example event data values and properties
startTime long: millis
490646260009
statistics G1EvacuationStatistics
allocated ulong: bytes
668984
directAllocated ulong: bytes
157808
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1228
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
1
undoWaste ulong: bytes
0
used ulong: bytes
569504
wasted ulong: bytes
1352
Example event data values and properties
startTime long: millis
575583795
statistics G1EvacuationStatistics
allocated ulong: bytes
2097152
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
5
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
1
undoWaste ulong: bytes
0
used ulong: bytes
1967224
wasted ulong: bytes
63912
Example event data values and properties
startTime long: millis
457142963013
statistics G1EvacuationStatistics
allocated ulong: bytes
437376
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1083
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
1
undoWaste ulong: bytes
0
used ulong: bytes
261992
wasted ulong: bytes
40

G1EvacuationOldStatistics

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Memory related evacuation statistics during GC for the old generation

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/g1/g1Trace.cpp:

  s.set_failureWaste(summary.failure_waste() * HeapWordSize);
  return s;
}

void G1NewTracer::send_young_evacuation_statistics(const G1EvacSummary& summary) const {
  EventG1EvacuationYoungStatistics surv_evt;
  if (surv_evt.should_commit()) {
    surv_evt.set_statistics(create_g1_evacstats(GCId::current(), summary));
    surv_evt.commit();
  }
}

void G1NewTracer::send_old_evacuation_statistics(const G1EvacSummary& summary) const {
  EventG1EvacuationOldStatistics old_evt;
  if (old_evt.should_commit()) {
    old_evt.set_statistics(create_g1_evacstats(GCId::current(), summary));
    old_evt.commit();
  }
}

void G1NewTracer::send_basic_ihop_statistics(size_t threshold,
                                             size_t target_occupancy,
                                             size_t non_young_occupancy) {
  EventG1BasicIHOP evt;
  if (evt.should_commit()) {

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
statistics G1EvacuationStatistics struct Evacuation Statistics

Examples 3
Example event data values and properties
startTime long: millis
1881001994
statistics G1EvacuationStatistics
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
61
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
0
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0
Example event data values and properties
startTime long: millis
492893100756
statistics G1EvacuationStatistics
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1238
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
0
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0
Example event data values and properties
startTime long: millis
453279126811
statistics G1EvacuationStatistics
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1068
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
0
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0

G1BasicIHOP

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Basic statistics related to current IHOP calculation

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/g1/g1Trace.cpp:

void G1NewTracer::send_old_evacuation_statistics(const G1EvacSummary& summary) const {
  EventG1EvacuationOldStatistics old_evt;
  if (old_evt.should_commit()) {
    old_evt.set_statistics(create_g1_evacstats(GCId::current(), summary));
    old_evt.commit();
  }
}

void G1NewTracer::send_basic_ihop_statistics(size_t threshold,
                                             size_t target_occupancy,
                                             size_t non_young_occupancy) {
  EventG1BasicIHOP evt;
  if (evt.should_commit()) {
    evt.set_gcId(GCId::current());
    evt.set_threshold(threshold);
    evt.set_targetOccupancy(target_occupancy);
    evt.set_thresholdPercentage(target_occupancy > 0 ? ((double)threshold / target_occupancy) : 0.0);
    evt.set_currentOccupancy(non_young_occupancy);
    evt.commit();
  }
}

void G1NewTracer::send_adaptive_ihop_statistics(size_t threshold,

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
threshold ulong: bytes Current IHOP Threshold Current IHOP threshold
thresholdPercentage float: percentage Current IHOP Threshold Current IHOP threshold in percent of old generation
targetOccupancy ulong: bytes Target Occupancy Target old generation occupancy to reach at the start of mixed GC
currentOccupancy ulong: bytes Current Occupancy Current old generation occupancy

Examples 3
Example event data values and properties
currentOccupancy ulong: bytes
468137384
gcId uint
1186
startTime long: millis
480763031921
targetOccupancy ulong: bytes
931135488
threshold ulong: bytes
0
thresholdPercentage float: percentage
0.0
Example event data values and properties
currentOccupancy ulong: bytes
14381856
gcId uint
6
startTime long: millis
612692308
targetOccupancy ulong: bytes
67108864
threshold ulong: bytes
30198988
thresholdPercentage float: percentage
0.45
Example event data values and properties
currentOccupancy ulong: bytes
257730248
gcId uint
1158
startTime long: millis
479548813144
targetOccupancy ulong: bytes
868220928
threshold ulong: bytes
108145660
thresholdPercentage float: percentage
0.12456007

G1AdaptiveIHOP

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Statistics related to current adaptive IHOP calculation

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/g1/g1Trace.cpp:

void G1NewTracer::send_adaptive_ihop_statistics(size_t threshold,
                                                size_t internal_target_occupancy,
                                                size_t current_occupancy,
                                                size_t additional_buffer_size,
                                                size_t non_humongous_allocation,
                                                size_t peak_extra_humongous_occupancy,
                                                double predicted_old_non_hum_alloc_rate,
                                                size_t predicted_peak_extra_humongous_occupancy,
                                                double predicted_marking_length,
                                                bool prediction_active) {
  EventG1AdaptiveIHOP evt;
  if (evt.should_commit()) {
    evt.set_gcId(GCId::current());
    evt.set_threshold(threshold);
    evt.set_thresholdPercentage(internal_target_occupancy > 0 ? ((double)threshold / internal_target_occupancy) : 0.0);
    evt.set_ihopTargetOccupancy(internal_target_occupancy);
    evt.set_currentOccupancy(current_occupancy);
    evt.set_additionalBufferSize(additional_buffer_size);
    evt.set_nonHumongousAllocation(non_humongous_allocation);
    evt.set_peakExtraHumongousOccupancy(peak_extra_humongous_occupancy);
    evt.set_predictedNonHumongousAllocation(predicted_old_non_hum_alloc_rate);
    evt.set_predictedPeakExtraHumongousOccupancy(predicted_peak_extra_humongous_occupancy);

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
threshold ulong: bytes Threshold Current IHOP Threshold
thresholdPercentage float: percentage Threshold Current IHOP threshold in percent of the internal target occupancy
ihopTargetOccupancy ulong: bytes IHOP Target Occupancy Internal target old generation occupancy to reach at the start of mixed GC
currentOccupancy ulong: bytes Current Occupancy Current old generation occupancy
nonHumongousAllocation ulong: bytes 27+ Current Non-Humongous Allocation Current non-humongous allocation accumulated by the concurrent cycle tracker
peakExtraHumongousOccupancy ulong: bytes 27+ Current Peak Extra Humongous Occupancy Current peak increase in humongous occupancy relative to the occupancy at concurrent cycle start
additionalBufferSize ulong: bytes Additional Buffer Additional buffer size
predictedNonHumongousAllocation double: bytes-per-second 27+ Predicted Non-Humongous Allocation Rate Predicted allocation rate of non-humongous objects into the old generation, in bytes per second
predictedPeakExtraHumongousOccupancy ulong: bytes 27+ Predicted Peak Extra Humongous Occupancy Predicted peak increase in humongous occupancy during a concurrent cycle relative to the occupancy at concurrent cycle start
predictedMarkingDuration long: millis Predicted Marking Duration Current predicted time from the end of the last concurrent start to the first mixed GC
predictionActive boolean Prediction Active Indicates whether the adaptive IHOP prediction is active

Examples 3
Example event data values and properties
additionalBufferSize ulong: bytes
383778816
currentOccupancy ulong: bytes
585798808
gcId uint
1140
ihopTargetOccupancy ulong: bytes
2091909120
predictedMarkingDuration long: millis
1507
predictionActive boolean
true
startTime long: millis
473413415317
threshold ulong: bytes
1476848828
thresholdPercentage float: percentage
0.7059814
Example event data values and properties
additionalBufferSize ulong: bytes
65011712
currentOccupancy ulong: bytes
9716008
gcId uint
202
ihopTargetOccupancy ulong: bytes
139460608
predictedMarkingDuration long: millis
100
predictionActive boolean
false
startTime long: millis
3578879670
threshold ulong: bytes
66060288
thresholdPercentage float: percentage
0.47368422
Example event data values and properties
additionalBufferSize ulong: bytes
562036736
currentOccupancy ulong: bytes
276285512
gcId uint
1221
ihopTargetOccupancy ulong: bytes
890555596
predictedMarkingDuration long: millis
1969
predictionActive boolean
true
startTime long: millis
488305530922
threshold ulong: bytes
0
thresholdPercentage float: percentage
0.0

PromoteObjectInNewPLAB

profiling startTime eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC

Missing in: graalvm_linux_native, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Object survived scavenge and was copied to a new Promotion Local Allocation Buffer (PLAB). Supported GCs are Parallel Scavenge, G1 and CMS with Parallel New. Due to promotion being done in parallel an object might be reported multiple times as the GC threads race to copy all objects.

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

void YoungGCTracer::send_young_gc_event() const {
  EventYoungGarbageCollection e(UNTIMED);
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_tenuringThreshold(_tenuring_threshold);
    e.set_starttime(_shared_gc_info.start_timestamp());
    e.set_endtime(_shared_gc_info.end_timestamp());
    e.commit();
  }
}

bool YoungGCTracer::should_send_promotion_in_new_plab_event() const {
  return EventPromoteObjectInNewPLAB::is_enabled();
}

bool YoungGCTracer::should_send_promotion_outside_plab_event() const {
  return EventPromoteObjectOutsidePLAB::is_enabled();
}

void YoungGCTracer::send_promotion_in_new_plab_event(Klass* klass, size_t obj_size,
                                                     uint age, bool tenured,
                                                     size_t plab_size) const {

  EventPromoteObjectInNewPLAB event;
  if (event.should_commit()) {
    event.set_gcId(GCId::current());
    event.set_objectClass(klass);
    event.set_objectSize(obj_size);
    event.set_tenured(tenured);
    event.set_tenuringAge(age);
    event.set_plabSize(plab_size);
    event.commit();
  }
}

Event configuration settings across JFR profiles
Configuration enabled
default false
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier Identifier signifying GC during which the object was promoted
objectClass Class Object Class Class of promoted object
objectSize ulong: bytes Object Size Size of promoted object
tenuringAge uint Object Tenuring Age Tenuring age of a surviving object before being copied. The tenuring age of an object is a value between 0-15 and is incremented each scavenge the object survives. Newly allocated objects have tenuring age 0.
tenured boolean Tenured True if object was promoted to Old space, otherwise the object was aged and copied to a Survivor space
plabSize ulong: bytes PLAB Size Size of the allocated PLAB to which the object was copied

Examples 3
Example event data values and properties
gcId uint
4
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
objectSize ulong: bytes
4112
plabSize ulong: bytes
26456
startTime long: millis
570074376
tenured boolean
false
tenuringAge uint
0
Example event data values and properties
gcId uint
1071
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
24
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionNode
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent/locks
objectSize ulong: bytes
32
plabSize ulong: bytes
2048
startTime long: millis
454585896176
tenured boolean
true
tenuringAge uint
0
Example event data values and properties
gcId uint
352
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
objectSize ulong: bytes
7512
plabSize ulong: bytes
32760
startTime long: millis
465224340730
tenured boolean
false
tenuringAge uint
0

PromoteObjectOutsidePLAB

profiling startTime eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC

Missing in: graalvm_linux_native, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Object survived scavenge and was copied directly to the heap. Supported GCs are Parallel Scavenge, G1 and CMS with Parallel New. Due to promotion being done in parallel an object might be reported multiple times as the GC threads race to copy all objects.

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

    e.set_gcId(GCId::current());
    e.set_tenuringThreshold(_tenuring_threshold);
    e.set_starttime(_shared_gc_info.start_timestamp());
    e.set_endtime(_shared_gc_info.end_timestamp());
    e.commit();
  }
}

bool YoungGCTracer::should_send_promotion_in_new_plab_event() const {
  return EventPromoteObjectInNewPLAB::is_enabled();
}

bool YoungGCTracer::should_send_promotion_outside_plab_event() const {
  return EventPromoteObjectOutsidePLAB::is_enabled();
}

void YoungGCTracer::send_promotion_in_new_plab_event(Klass* klass, size_t obj_size,
                                                     uint age, bool tenured,
                                                     size_t plab_size) const {

  EventPromoteObjectInNewPLAB event;
  if (event.should_commit()) {
    event.set_gcId(GCId::current());
    event.set_objectClass(klass);
    event.set_objectSize(obj_size);
    event.set_tenured(tenured);
    event.set_tenuringAge(age);
    event.set_plabSize(plab_size);
    event.commit();
  }
}

void YoungGCTracer::send_promotion_outside_plab_event(Klass* klass, size_t obj_size,
                                                      uint age, bool tenured) const {

  EventPromoteObjectOutsidePLAB event;
  if (event.should_commit()) {
    event.set_gcId(GCId::current());
    event.set_objectClass(klass);
    event.set_objectSize(obj_size);
    event.set_tenured(tenured);
    event.set_tenuringAge(age);
    event.commit();
  }
}

void OldGCTracer::send_old_gc_event() const {

Event configuration settings across JFR profiles
Configuration enabled
default false
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier Identifier signifying GC during which the object was promoted
objectClass Class Object Class Class of promoted object
objectSize ulong: bytes Object Size Size of promoted object
tenuringAge uint Object Tenuring Age Tenuring age of a surviving object before being copied. The tenuring age of an object is a value between 0-15 and is incremented each scavenge the object survives. Newly allocated objects have tenuring age 0.
tenured boolean Tenured True if object was promoted to Old space, otherwise the object was aged and copied to a Survivor space

Examples 3
Example event data values and properties
gcId uint
353
objectClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1041
name string
[Lorg/apache/spark/unsafe/memory/MemoryBlock;
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/unsafe/memory
objectSize ulong: bytes
32784
startTime long: millis
466147037157
tenured boolean
false
tenuringAge uint
0
Example event data values and properties
gcId uint
1
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
objectSize ulong: bytes
4112
startTime long: millis
564247367
tenured boolean
false
tenuringAge uint
0
Example event data values and properties
gcId uint
1070
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
objectSize ulong: bytes
29384
startTime long: millis
454094508343
tenured boolean
false
tenuringAge uint
0

PromotionFailed

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Promotion of an object failed

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

static JfrStructCopyFailed to_struct(const CopyFailedInfo& cf_info) {
  JfrStructCopyFailed failed_info;
  failed_info.set_objectCount(cf_info.failed_count());
  failed_info.set_firstSize(cf_info.first_size() * HeapWordSize);
  failed_info.set_smallestSize(cf_info.smallest_size() * HeapWordSize);
  failed_info.set_totalSize(cf_info.total_size() * HeapWordSize);
  return failed_info;
}

void YoungGCTracer::send_promotion_failed_event(const PromotionFailedInfo& pf_info) const {
  EventPromotionFailed e;
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_promotionFailed(to_struct(pf_info));
    e.set_thread(pf_info.thread_trace_id());
    e.commit();
  }
}

// G1
void OldGCTracer::send_concurrent_mode_failure_event() {
  EventConcurrentModeFailure e;

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
promotionFailed CopyFailed struct Promotion Failed Data
thread Thread Running Thread

EvacuationFailed

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Evacuation of an object failed

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/g1/g1Trace.cpp:

    e.set_cSetRegions(info->collection_set_regions());
    e.set_cSetUsedBefore(info->collection_set_used_before());
    e.set_cSetUsedAfter(info->collection_set_used_after());
    e.set_allocationRegions(info->allocation_regions());
    e.set_allocationRegionsUsedBefore(info->alloc_regions_used_before());
    e.set_allocationRegionsUsedAfter(info->alloc_regions_used_before() + info->bytes_used());
    e.set_bytesCopied(info->bytes_used());
    e.set_regionsFreed(info->regions_freed());
    e.commit();
  }
}

void G1NewTracer::send_evacuation_failed_event(const EvacuationFailedInfo& ef_info) const {
  EventEvacuationFailed e;
  if (e.should_commit()) {
    // Create JFR structured failure data
    JfrStructCopyFailed evac_failed;
    evac_failed.set_objectCount(ef_info.failed_count());
    evac_failed.set_firstSize(ef_info.first_size() * HeapWordSize);
    evac_failed.set_smallestSize(ef_info.smallest_size() * HeapWordSize);
    evac_failed.set_totalSize(ef_info.total_size() * HeapWordSize);
    // Add to the event
    e.set_gcId(GCId::current());
    e.set_evacuationFailed(evac_failed);
    e.commit();

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
evacuationFailed CopyFailed struct Evacuation Failed Data

ConcurrentModeFailure

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Concurrent Mode failed

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

void YoungGCTracer::send_promotion_failed_event(const PromotionFailedInfo& pf_info) const {
  EventPromotionFailed e;
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_promotionFailed(to_struct(pf_info));
    e.set_thread(pf_info.thread_trace_id());
    e.commit();
  }
}

// G1
void OldGCTracer::send_concurrent_mode_failure_event() {
  EventConcurrentModeFailure e;
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.commit();
  }
}

static JfrStructVirtualSpace to_struct(const VirtualSpaceSummary& summary) {
  JfrStructVirtualSpace space;
  space.set_start((TraceAddress)summary.start());
  space.set_committedEnd((TraceAddress)summary.committed_end());
  space.set_committedSize(summary.committed_size());

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier

Examples 3
Example event data values and properties
gcId uint
1175
startTime long: millis
476967872715
Example event data values and properties
gcId uint
1940
startTime long: millis
25328741359
Example event data values and properties
gcId uint
1135
startTime long: millis
472257027096

GCCPUTime

default profiling startTime 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

GC CPU Time information. Supported: G1GC, ParallelGC and SerialGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

// All GC dependencies against the trace framework is contained within this file.

typedef uintptr_t TraceAddress;

bool GCTracer::should_send_cpu_time_event() const {
  return EventGCCPUTime::is_enabled();
}

void GCTracer::send_garbage_collection_event() const {
  EventGarbageCollection event(UNTIMED);
  if (event.should_commit()) {
    event.set_gcId(GCId::current());
    event.set_name(_shared_gc_info.name());
    event.set_cause((u2) _shared_gc_info.cause());
    event.set_sumOfPauses(_shared_gc_info.sum_of_pauses());
    event.set_longestPause(_shared_gc_info.longest_pause());
    event.set_starttime(_shared_gc_info.start_timestamp());
    event.set_endtime(_shared_gc_info.end_timestamp());
    event.commit();
  }
}

void GCTracer::send_cpu_time_event(double user_time, double system_time, double real_time) const {
  EventGCCPUTime e;
  if (e.should_commit()) {
      e.set_gcId(GCId::current());
      e.set_userTime((size_t)(user_time * NANOUNITS));
      e.set_systemTime((size_t)(system_time * NANOUNITS));
      e.set_realTime((size_t)(real_time * NANOUNITS));
      e.commit();
  }
}

void GCTracer::send_reference_stats_event(ReferenceType type, size_t count) const {
  EventGCReferenceStatistics e;

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
userTime ulong: nanos User Time
systemTime ulong: nanos System Time
realTime ulong: nanos Real Time

Examples 3
Example event data values and properties
gcId uint
1117
realTime ulong: nanos
10000000
startTime long: millis
467153782004
systemTime ulong: nanos
0
userTime ulong: nanos
9999999
Example event data values and properties
gcId uint
346
realTime ulong: nanos
200000000
startTime long: millis
455792514906
systemTime ulong: nanos
0
userTime ulong: nanos
639999999
Example event data values and properties
gcId uint
13
realTime ulong: nanos
0
startTime long: millis
779485113
systemTime ulong: nanos
0
userTime ulong: nanos
9999999

AllocationRequiringGC

startTime eventThread stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/allocTracer.cpp:

    event.set_allocationSize(alloc_size);
    event.commit();
  }
}

void AllocTracer::send_allocation_in_new_tlab(Klass* klass, HeapWord* obj, size_t tlab_size, size_t alloc_size, JavaThread* thread) {
  JFR_ONLY(JfrAllocationTracer tracer(klass, obj, alloc_size, false, thread);)
  EventObjectAllocationInNewTLAB event;
  if (event.should_commit()) {
    event.set_objectClass(klass);
    event.set_allocationSize(alloc_size);
    event.set_tlabSize(tlab_size);
    event.commit();
  }
}

void AllocTracer::send_allocation_requiring_gc_event(size_t size, uint gcId) {
  EventAllocationRequiringGC event;
  if (event.should_commit()) {
    event.set_gcId(gcId);
    event.set_size(size);
    event.commit();
  }
}

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default false true
profiling false true

Event fields with their types and descriptions
Field Type Description
gcId uint Pending GC Identifier
size ulong: bytes Allocation Size

Examples 3
Example event data values and properties
gcId uint
1104
size ulong: bytes
11728
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
15
lineNumber int
3537
method Method
descriptor string
([BI)[B
hidden boolean
false
modifiers int
9
name string
copyOf
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/util/Arrays
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
type FrameType
JIT compiled
…
truncated boolean
true
startTime long: millis
463178195781
Example event data values and properties
gcId uint
71
size ulong: bytes
4112
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
24
lineNumber int
494
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
allocateAndGC
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
2000198202
Example event data values and properties
gcId uint
360
size ulong: bytes
16
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
177
method Method
descriptor string
(ILjava/util/stream/Sink;)Ljava/util/stream/Sink;
hidden boolean
false
modifiers int
0
name string
opWrapSink
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/util/stream/IntPipeline$1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/stream
type FrameType
JIT compiled
…
truncated boolean
true
startTime long: millis
476310842808

TenuringDistribution

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_ShenandoahGC, linux_ZGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/ageTableTracer.cpp:

void AgeTableTracer::send_tenuring_distribution_event(uint age, size_t size) {
  EventTenuringDistribution e;
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_age(age);
    e.set_size(size);
    e.commit();
  }
}

bool AgeTableTracer::is_tenuring_distribution_event_enabled() {
  return EventTenuringDistribution::is_enabled();
}

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
age uint Age
size ulong: bytes Size

Examples 3
Example event data values and properties
age uint
8
gcId uint
1359
size ulong: bytes
0
startTime long: millis
555586444626
Example event data values and properties
age uint
5
gcId uint
1072
size ulong: bytes
0
startTime long: millis
454878079478
Example event data values and properties
age uint
3
gcId uint
7
size ulong: bytes
0
startTime long: millis
624773352

G1HeapRegionTypeChange

startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Information about a G1 heap region type change

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/g1/g1HeapRegionTracer.cpp:

void G1HeapRegionTracer::send_region_type_change(uint index,
                                               G1HeapRegionTraceType::Type from,
                                               G1HeapRegionTraceType::Type to,
                                               uintptr_t start,
                                               size_t used) {
  EventG1HeapRegionTypeChange e;
  if (e.should_commit()) {
    e.set_index(index);
    e.set_from(from);
    e.set_to(to);
    e.set_start(start);
    e.set_used(used);
    e.commit();
  }
}

Event configuration settings across JFR profiles
Configuration enabled
default false
profiling false

Event fields with their types and descriptions
Field Type Description
index uint Index
from G1HeapRegionType From
to G1HeapRegionType To
start ulong: address Start
used ulong: bytes Used

Examples 3
Example event data values and properties
from G1HeapRegionType
Free
index uint
399
start ulong: address
31002198016
startTime long: millis
475422556027
to G1HeapRegionType
Eden
used ulong: bytes
0
Example event data values and properties
from G1HeapRegionType
Free
index uint
100
start ulong: address
30377246720
startTime long: millis
453047488022
to G1HeapRegionType
Starts Humongous
used ulong: bytes
0
Example event data values and properties
from G1HeapRegionType
Eden
index uint
12
start ulong: address
30192697344
startTime long: millis
565522292
to G1HeapRegionType
Free
used ulong: bytes
0

ObjectCount

startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/objectCountEventSender.cpp:

template <typename T>
void ObjectCountEventSender::send_event_if_enabled(Klass* klass, jlong count, julong size, const Ticks& timestamp) {
  T event(UNTIMED);
  if (event.should_commit()) {
    event.set_starttime(timestamp);
    event.set_endtime(timestamp);
    event.set_gcId(GCId::current());
    event.set_objectClass(klass);
    event.set_count(count);
    event.set_totalSize(size);
    event.commit();
  }
}

void ObjectCountEventSender::send(const KlassInfoEntry* entry, const Ticks& timestamp) {
  Klass* klass = entry->klass();
  jlong count = entry->count();
  julong total_size = entry->words() * BytesPerWord;

  send_event_if_enabled<EventObjectCount>(klass, count, total_size, timestamp);
  send_event_if_enabled<EventObjectCountAfterGC>(klass, count, total_size, timestamp);
}

#endif // INCLUDE_SERVICES

Event configuration settings across JFR profiles
Configuration enabled period
default false everyChunk
profiling false everyChunk

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
objectClass Class Object Class
count long Count
totalSize ulong: bytes Total Size

Examples 3
Example event data values and properties
count long
5485
gcId uint
1067
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[C
package Package
null
startTime long: millis
453199618606
totalSize ulong: bytes
6058648
Example event data values and properties
count long
43978
gcId uint
339
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
16
name string
jdk/internal/util/WeakReferenceKey
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/util
startTime long: millis
449182893333
totalSize ulong: bytes
1407296
Example event data values and properties
count long
843
gcId uint
31
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/jfr/ValueDescriptor
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.jfr
name string
jdk.jfr
version string
25.0.4.1
name string
jdk/jfr
startTime long: millis
1547566847
totalSize ulong: bytes
33720

G1HeapRegionInformation

startTime duration every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Information about a specific heap region in the G1 GC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/g1/g1HeapRegionEventSender.cpp:

class DumpEventInfoClosure : public G1HeapRegionClosure {
public:
  bool do_heap_region(G1HeapRegion* r) {
    EventG1HeapRegionInformation evt;
    evt.set_index(r->hrm_index());
    evt.set_type(r->get_trace_type());
    evt.set_start((uintptr_t)r->bottom());
    evt.set_used(r->used());
    evt.commit();
    return false;
  }
};

class VM_G1SendHeapRegionInfoEvents : public VM_Operation {
  virtual void doit() {
    DumpEventInfoClosure c;
    G1CollectedHeap::heap()->heap_region_iterate(&c);

Event configuration settings across JFR profiles
Configuration enabled period
default false everyChunk
profiling false everyChunk

Event fields with their types and descriptions
Field Type Description
index uint Index
type G1HeapRegionType Type
start ulong: address Start
used ulong: bytes Used

Examples 3
Example event data values and properties
index uint
530
start ulong: address
31276924928
startTime long: millis
476970618437
type G1HeapRegionType
Continues Humongous
used ulong: bytes
2097152
Example event data values and properties
index uint
2
start ulong: address
30171725824
startTime long: millis
23271455045
type G1HeapRegionType
Old
used ulong: bytes
2097120
Example event data values and properties
index uint
274
start ulong: address
30742151168
startTime long: millis
453269697636
type G1HeapRegionType
Free
used ulong: bytes
0

ZAllocationStall

default profiling startTime duration eventThread stackTrace 15 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Time spent waiting for memory to become available

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/z/zPageAllocator.cpp:

  if (harvested > 0) {
    ZStatInc(ZCounterMappedCacheHarvest, harvested);
    log_debug(gc, heap)("Mapped Cache Harvested: %zuM (%d)", harvested / M, num_harvested_vmems);
  }

  // Send event for successful allocation
  allocation.send_event(true /* successful */);

  return page;
}

bool ZPageAllocator::alloc_page_stall(ZPageAllocation* allocation) {
  ZStatTimer timer(ZCriticalPhaseAllocationStall);
  EventZAllocationStall event;

  // We can only block if the VM is fully initialized
  check_out_of_memory_during_initialization();

  // Start asynchronous minor GC
  const ZDriverRequest request(GCCause::_z_allocation_stall, ZYoungGCThreads, 0);
  ZDriver::minor()->collect(request);

  // Wait for allocation to complete or fail
  const bool result = allocation->wait();

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 17+ 0 ms
profiling true true 17+ 0 ms

Event fields with their types and descriptions
Field Type Description
type ZPageTypeType Type
size ulong: bytes Size

ZPageAllocation

default profiling startTime duration eventThread stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Allocation of a ZPage

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/z/zPageAllocator.cpp:

          _multi_partition_allocation.sum_num_harvested_vmems(),
          _multi_partition_allocation.sum_harvested(),
          _multi_partition_allocation.sum_committed_increased_capacity());
    } else {
      return ZPageAllocationStats(
          _single_partition_allocation.allocation()->num_harvested(),
          _single_partition_allocation.allocation()->harvested(),
          _single_partition_allocation.allocation()->committed_capacity());
    }
  }

  void send_event(bool successful) {
    if (!EventZPageAllocation::is_enabled()) {
      // Event not enabled, exit early
      return;
    }

    Ticks end_timestamp = Ticks::now();
    const ZPageAllocationStats st = stats();

    EventZPageAllocation::commit(_start_timestamp,
                                 end_timestamp,
                                 (u8)_type,
                                 size(),
                                 st._total_harvested,
                                 st._total_committed_capacity,
                                 (unsigned)st._num_harvested_vmems,
                                 _is_multi_partition,
                                 successful,
                                 _flags.non_blocking());
  }
};

src/hotspot/share/gc/z/zPageAllocator.cpp:

  assert(to->age() == ZPageAge::old,   "must be promotion");

  decrease_used_generation(ZGenerationId::young, to->size());
  increase_used_generation(ZGenerationId::old, to->size());
}

static void check_out_of_memory_during_initialization() {
  if (!is_init_completed()) {
    vm_exit_during_initialization("java.lang.OutOfMemoryError", "Java heap too small");
  }
}

ZPage* ZPageAllocator::alloc_page(ZPageType type, size_t size, ZAllocationFlags flags, ZPageAge age, uint32_t preferred_partition) {
  EventZPageAllocation event;

  ZPageAllocation allocation(type, size, flags, age, preferred_partition);

  // Allocate the page
  ZPage* const page = alloc_page_inner(&allocation);
  if (page == nullptr) {
    return nullptr;
  }

  // Update allocation statistics. Exclude gc relocations to avoid
  // artificial inflation of the allocation rate during relocation.

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 15+ 1 ms
profiling true true 15+ 1 ms

Event fields with their types and descriptions
Field Type Description
type ZPageTypeType 15+ Type
size ulong: bytes 15+ Size
harvested ulong: bytes 25+ Harvested
committed ulong: bytes 15+ Committed
harvestedRanges uint 25+ Harvested Ranges Number of harvested memory ranges
multiPartition boolean 25+ Multi-Partition
successful boolean 25+ Successful
nonBlocking boolean Non-Blocking

Examples 2
Example event data values and properties
committed ulong: bytes
0
harvested ulong: bytes
0
harvestedRanges uint
0
multiPartition boolean
false
nonBlocking boolean
true
size ulong: bytes
33554432
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
15
lineNumber int
3537
method Method
descriptor string
([BI)[B
hidden boolean
false
modifiers int
9
name string
copyOf
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/util/Arrays
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
type FrameType
JIT compiled
…
truncated boolean
true
startTime long: millis
621220828034
successful boolean
true
type ZPageTypeType
Medium
Example event data values and properties
committed ulong: bytes
2097152
harvested ulong: bytes
0
harvestedRanges uint
0
multiPartition boolean
false
nonBlocking boolean
false
size ulong: bytes
2097152
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
24
lineNumber int
494
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
allocateAndGC
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
889005581
successful boolean
true
type ZPageTypeType
Small

ZRelocationSet

default profiling startTime duration eventThread 15 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/z/zRelocationSetSelector.cpp:

ZRelocationSetSelector::ZRelocationSetSelector(double fragmentation_limit)
  : _small("Small", ZPageType::small, ZPageSizeSmall, ZObjectSizeLimitSmall, fragmentation_limit),
    _medium("Medium", ZPageType::medium, ZPageSizeMediumMax, ZObjectSizeLimitMedium, fragmentation_limit),
    _large("Large", ZPageType::large, 0 /* max_page_size */, 0 /* object_size_limit */, fragmentation_limit),
    _empty_pages() {}

void ZRelocationSetSelector::select() {
  // Select pages to relocate. The resulting relocation set will be
  // sorted such that medium pages comes first, followed by small
  // pages. Pages within each page group will be semi-sorted by live
  // bytes in ascending order. Relocating pages in this order allows
  // us to start reclaiming memory more quickly.

  EventZRelocationSet event;

  // Select pages from each group
  _large.select();
  _medium.select();
  _small.select();

  // Send event
  event.commit(total(), empty(), relocate());
}

ZRelocationSetSelectorStats ZRelocationSetSelector::stats() const {

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
total ulong: bytes Total
empty ulong: bytes Empty
relocate ulong: bytes 16+ Relocate

Examples 2
Example event data values and properties
empty ulong: bytes
2426404864
relocate ulong: bytes
3947536
startTime long: millis
644964786499
total ulong: bytes
3172990976
Example event data values and properties
empty ulong: bytes
0
relocate ulong: bytes
0
startTime long: millis
1584797211
total ulong: bytes
44040192

ZRelocationSetGroup

default profiling startTime duration eventThread 15 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/z/zRelocationSetSelector.cpp:

    _stats[i]._relocate = live_bytes_per_age[i] - rejected_live_bytes_per_age[i];
    _stats[i]._npages_selected = npages_per_age[i] - rejected_npages_per_age[i];
  }

  log_debug(gc, reloc)("Relocation Set (%s Pages): %d->%d, %d skipped, %zu forwarding entries",
                       _name, selected_from, selected_to, npages - selected_from, selected_forwarding_entries);
}

void ZRelocationSetSelectorGroup::select() {
  if (is_disabled()) {
    return;
  }

  EventZRelocationSetGroup event;

  if (is_selectable()) {
    select_inner();
  } else {
    // Mark pages as not selected
    const int npages = _live_pages.length();
    for (int from = 1; from <= npages; from++) {
      ZPage* const page = _live_pages.at(from - 1);
      _not_selected_pages.append(page);
    }
  }

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
type ZPageTypeType Type
candidatePages ulong 21+ Candidate Pages
total ulong: bytes Total
empty ulong: bytes Empty
selectedPages ulong 21+ Selected Pages
relocate ulong: bytes 16+ Relocate

Examples 2
Example event data values and properties
candidatePages ulong
0
empty ulong: bytes
0
relocate ulong: bytes
0
selectedPages ulong
0
startTime long: millis
1772281937
total ulong: bytes
0
type ZPageTypeType
Large
Example event data values and properties
candidatePages ulong
2
empty ulong: bytes
12582912
relocate ulong: bytes
0
selectedPages ulong
0
startTime long: millis
645988170534
total ulong: bytes
12582912
type ZPageTypeType
Large

ZStatisticsCounter

experimental startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/z/zTracer.cpp:

  e.set_gcId(GCId::current());
  e.set_starttime(_start);
  e.set_endtime(timestamp);
  e.commit();
}

void ZTracer::initialize() {
  JFR_ONLY(register_jfr_type_serializers();)
}

void ZTracer::send_stat_counter(const ZStatCounter& counter, uint64_t increment, uint64_t value) {
  NoSafepointVerifier nsv;

  JfrNonReentrant<EventZStatisticsCounter> e;
  if (e.should_commit()) {
    e.set_id(counter.id());
    e.set_increment(increment);
    e.set_value(value);
    e.commit();
  }
}

void ZTracer::send_stat_sampler(const ZStatSampler& sampler, uint64_t value) {
  NoSafepointVerifier nsv;

src/hotspot/share/gc/z/zTracer.inline.hpp:

#ifndef SHARE_GC_Z_ZTRACER_INLINE_HPP
#define SHARE_GC_Z_ZTRACER_INLINE_HPP

#include "gc/z/zTracer.hpp"

#include "jfr/jfrEvents.hpp"

inline void ZTracer::report_stat_counter(const ZStatCounter& counter, uint64_t increment, uint64_t value) {
  if (EventZStatisticsCounter::is_enabled()) {
    send_stat_counter(counter, increment, value);
  }
}

inline void ZTracer::report_stat_sampler(const ZStatSampler& sampler, uint64_t value) {
  if (EventZStatisticsSampler::is_enabled()) {
    send_stat_sampler(sampler, value);
  }
}

inline void ZTracer::report_thread_phase(const char* name, const Ticks& start, const Ticks& end) {
  if (EventZThreadPhase::is_enabled()) {
    send_thread_phase(name, start, end);
  }
}

Event configuration settings across JFR profiles
Configuration enabled threshold
default false 0 ms
profiling false 0 ms

Event fields with their types and descriptions
Field Type Description
id ZStatisticsCounterType Id
increment ulong Increment
value ulong Value

Examples 2
Example event data values and properties
id ZStatisticsCounterType
Allocation Rate
increment ulong
2097152
startTime long: millis
757883510
value ulong
85983232
Example event data values and properties
id ZStatisticsCounterType
Allocation Rate
increment ulong
2097152
startTime long: millis
619124365020
value ulong
10485760

ZStatisticsSampler

experimental startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/z/zTracer.cpp:

  JfrNonReentrant<EventZStatisticsCounter> e;
  if (e.should_commit()) {
    e.set_id(counter.id());
    e.set_increment(increment);
    e.set_value(value);
    e.commit();
  }
}

void ZTracer::send_stat_sampler(const ZStatSampler& sampler, uint64_t value) {
  NoSafepointVerifier nsv;

  JfrNonReentrant<EventZStatisticsSampler> e;
  if (e.should_commit()) {
    e.set_id(sampler.id());
    e.set_value(value);
    e.commit();
  }
}

void ZTracer::send_thread_phase(const char* name, const Ticks& start, const Ticks& end) {
  NoSafepointVerifier nsv;

  EventZThreadPhase e(UNTIMED);

src/hotspot/share/gc/z/zTracer.inline.hpp:

#define SHARE_GC_Z_ZTRACER_INLINE_HPP

#include "gc/z/zTracer.hpp"

#include "jfr/jfrEvents.hpp"

inline void ZTracer::report_stat_counter(const ZStatCounter& counter, uint64_t increment, uint64_t value) {
  if (EventZStatisticsCounter::is_enabled()) {
    send_stat_counter(counter, increment, value);
  }
}

inline void ZTracer::report_stat_sampler(const ZStatSampler& sampler, uint64_t value) {
  if (EventZStatisticsSampler::is_enabled()) {
    send_stat_sampler(sampler, value);
  }
}

inline void ZTracer::report_thread_phase(const char* name, const Ticks& start, const Ticks& end) {
  if (EventZThreadPhase::is_enabled()) {
    send_thread_phase(name, start, end);
  }
}

inline void ZTracer::report_thread_debug(const char* name, const Ticks& start, const Ticks& end) {

Event configuration settings across JFR profiles
Configuration enabled threshold
default false 0 ms
profiling false 0 ms

Event fields with their types and descriptions
Field Type Description
id ZStatisticsSamplerType Id
value ulong Value

Examples 2
Example event data values and properties
id ZStatisticsSamplerType
Concurrent Relocate
startTime long: millis
621311934026
value ulong
3383661
Example event data values and properties
id ZStatisticsSamplerType
Uncommit
startTime long: millis
1107375319
value ulong
0

ZThreadPhase

experimental startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/z/zTracer.cpp:

  NoSafepointVerifier nsv;

  JfrNonReentrant<EventZStatisticsSampler> e;
  if (e.should_commit()) {
    e.set_id(sampler.id());
    e.set_value(value);
    e.commit();
  }
}

void ZTracer::send_thread_phase(const char* name, const Ticks& start, const Ticks& end) {
  NoSafepointVerifier nsv;

  EventZThreadPhase e(UNTIMED);
  if (e.should_commit()) {
    e.set_gcId(GCId::current_or_undefined());
    e.set_name(name);
    e.set_starttime(start);
    e.set_endtime(end);
    e.commit();
  }
}

void ZTracer::send_thread_debug(const char* name, const Ticks& start, const Ticks& end) {
  NoSafepointVerifier nsv;

src/hotspot/share/gc/z/zTracer.inline.hpp:

inline void ZTracer::report_stat_counter(const ZStatCounter& counter, uint64_t increment, uint64_t value) {
  if (EventZStatisticsCounter::is_enabled()) {
    send_stat_counter(counter, increment, value);
  }
}

inline void ZTracer::report_stat_sampler(const ZStatSampler& sampler, uint64_t value) {
  if (EventZStatisticsSampler::is_enabled()) {
    send_stat_sampler(sampler, value);
  }
}

inline void ZTracer::report_thread_phase(const char* name, const Ticks& start, const Ticks& end) {
  if (EventZThreadPhase::is_enabled()) {
    send_thread_phase(name, start, end);
  }
}

inline void ZTracer::report_thread_debug(const char* name, const Ticks& start, const Ticks& end) {
  if (EventZThreadDebug::is_enabled()) {
    send_thread_debug(name, start, end);
  }
}

inline ZTraceThreadDebug::ZTraceThreadDebug(const char* name)

Event configuration settings across JFR profiles
Configuration enabled threshold
default false 0 ms
profiling false 0 ms

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
name string Name

Examples 2
Example event data values and properties
gcId uint
0
name string
Concurrent Roots ClassLoaderDataGraph
startTime long: millis
458309088
Example event data values and properties
gcId uint
258
name string
Concurrent Mark Root Colored
startTime long: millis
623982820279

ZUncommit

default profiling startTime duration eventThread 15 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Uncommitting of memory

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/z/zUncommitter.cpp:

bool ZUncommitter::should_continue() const {
  ZLocker<ZConditionLock> locker(&_lock);
  return !_stop;
}

void ZUncommitter::update_statistics(size_t uncommitted, Ticks start, Tickspan* accumulated_time) const {
  // Update counter
  ZStatInc(ZCounterUncommit, uncommitted);

  Ticks end = Ticks::now();

  // Send event
  EventZUncommit::commit(start, end, uncommitted);

  // Track accumulated time
  *accumulated_time += end - start;
}

void ZUncommitter::run_thread() {
  // Initialize first cycle timeout
  _next_cycle_timeout = to_millis(ZUncommitDelay);

  while (wait(_next_cycle_timeout)) {
    // Counters for event and statistics

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
uncommitted ulong: bytes Uncommitted

Examples 1
Example event data values and properties
startTime long: millis
663183551656
uncommitted ulong: bytes
33554432

ShenandoahHeapRegionStateChange

startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ShenandoahGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ZGC

Information about a Shenandoah heap region state change

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shenandoah/shenandoahHeapRegion.cpp:

void ShenandoahHeapRegion::do_uncommit() {
  ShenandoahHeap* heap = ShenandoahHeap::heap();
  if (!heap->is_heap_region_special()) {
    os::uncommit_memory((char *) bottom(), RegionSizeBytes);
  }
  if (!heap->is_bitmap_region_special()) {
    heap->uncommit_bitmap_slice(this);
  }
  heap->decrease_committed(ShenandoahHeapRegion::region_size_bytes());
}

void ShenandoahHeapRegion::set_state(RegionState to) {
  EventShenandoahHeapRegionStateChange evt;
  if (evt.should_commit()){
    evt.set_index((unsigned) index());
    evt.set_start((uintptr_t)bottom());
    evt.set_used(used());
    evt.set_from(state());
    evt.set_to(to);
    evt.commit();
  }
  _state.release_store(to);
}

Event configuration settings across JFR profiles
Configuration enabled
default false
profiling false

Event fields with their types and descriptions
Field Type Description
index uint Index
from ShenandoahHeapRegionState From
to ShenandoahHeapRegionState To
start ulong: address Start
used ulong: bytes Used

Examples 2
Example event data values and properties
from ShenandoahHeapRegionState
Empty Committed
index uint
3245
start ulong: address
33570160640
startTime long: millis
549817381465
to ShenandoahHeapRegionState
Empty Uncommitted
used ulong: bytes
0
Example event data values and properties
from ShenandoahHeapRegionState
Regular
index uint
8
start ulong: address
30175920128
startTime long: millis
379518570
to ShenandoahHeapRegionState
Collection Set
used ulong: bytes
1048576

ShenandoahHeapRegionInformation

startTime duration every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ShenandoahGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ZGC

Information about a specific heap region in the Shenandoah GC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shenandoah/shenandoahJfrSupport.cpp:

void ShenandoahJFRSupport::register_jfr_type_serializers() {
  JfrSerializer::register_serializer(TYPE_SHENANDOAHHEAPREGIONSTATE,
                                     true,
                                     new ShenandoahHeapRegionStateConstant());
}
#endif

class ShenandoahDumpHeapRegionInfoClosure : public ShenandoahHeapRegionClosure {
public:
  virtual void heap_region_do(ShenandoahHeapRegion* r) {
    EventShenandoahHeapRegionInformation evt;
    evt.set_index((unsigned) r->index());
    evt.set_state((u8)r->state());
    evt.set_start((uintptr_t)r->bottom());
    evt.set_used(r->used());
    evt.commit();
  }
};

void VM_ShenandoahSendHeapRegionInfoEvents::doit() {
  ShenandoahDumpHeapRegionInfoClosure c;
  ShenandoahHeap::heap()->heap_region_iterate(&c);

Event configuration settings across JFR profiles
Configuration enabled period
default false everyChunk
profiling false everyChunk

Event fields with their types and descriptions
Field Type Description
index uint Index
state ShenandoahHeapRegionState State
start ulong: address Start
used ulong: bytes Used

Examples 2
Example event data values and properties
index uint
65
start ulong: address
30235688960
startTime long: millis
388501784
state ShenandoahHeapRegionState
Empty Committed
used ulong: bytes
0
Example event data values and properties
index uint
51
start ulong: address
30221008896
startTime long: millis
551404916721
state ShenandoahHeapRegionState
Humongous Continuation
used ulong: bytes
16

ShenandoahEvacuationInformation

startTime 24 25 27 28

Category: Java Virtual Machine / GC / Detailed

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shenandoah/shenandoahTrace.cpp:

void ShenandoahTracer::report_evacuation_info(const ShenandoahCollectionSet* cset,
    size_t free_regions, size_t regions_immediate, size_t immediate_size) {

  EventShenandoahEvacuationInformation e;
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_cSetRegions(cset->count());
    e.set_cSetUsedBefore(cset->used());
    e.set_cSetUsedAfter(cset->live());
    e.set_freeRegions(free_regions);
    e.set_regionsImmediate(regions_immediate);
    e.set_immediateBytes(immediate_size);

    e.commit();
  }
}

void ShenandoahTracer::report_promotion_info(const ShenandoahCollectionSet* cset,
    size_t regions_promoted_humongous, size_t humongous_promoted_garbage, size_t humongous_promoted_free,
    size_t regions_promoted_regular, size_t regular_promoted_garbage, size_t regular_promoted_free) {

Event configuration settings across JFR profiles
Configuration enabled
default false
profiling false

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
cSetRegions ulong Collection Set Regions
cSetUsedBefore ulong: bytes Collection Set Before Memory usage before GC in the collection set regions
cSetUsedAfter ulong: bytes Collection Set After Memory usage after GC in the collection set regions
freeRegions ulong 25+ Free Regions Free regions prior to collection
regionsImmediate ulong Regions Immediate
immediateBytes ulong: bytes Immediate Bytes

ShenandoahPromotionInformation

startTime 27 28

Category: Java Virtual Machine / GC / Detailed

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shenandoah/shenandoahTrace.cpp:

    e.set_cSetUsedAfter(cset->live());
    e.set_freeRegions(free_regions);
    e.set_regionsImmediate(regions_immediate);
    e.set_immediateBytes(immediate_size);

    e.commit();
  }
}

void ShenandoahTracer::report_promotion_info(const ShenandoahCollectionSet* cset,
    size_t regions_promoted_humongous, size_t humongous_promoted_garbage, size_t humongous_promoted_free,
    size_t regions_promoted_regular, size_t regular_promoted_garbage, size_t regular_promoted_free) {

  EventShenandoahPromotionInformation e;
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_collectedOld(cset->get_live_bytes_in_old_regions());
    e.set_collectedPromoted(cset->get_live_bytes_in_tenurable_regions());
    e.set_collectedYoung(cset->get_live_bytes_in_untenurable_regions());
    e.set_regionsPromotedHumongous(regions_promoted_humongous);
    e.set_humongousPromotedGarbage(humongous_promoted_garbage);
    e.set_humongousPromotedFree(humongous_promoted_free);
    e.set_regionsPromotedRegular(regions_promoted_regular);
    e.set_regularPromotedGarbage(regular_promoted_garbage);
    e.set_regularPromotedFree(regular_promoted_free);

Event configuration settings across JFR profiles
Configuration enabled
default false
profiling false

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
collectedOld ulong: bytes Collected Old Memory collected from old generation
collectedPromoted ulong: bytes Collected Promoted Memory collected from generation promotion
collectedYoung ulong: bytes Collection Young Memory collected from young generation
regionsPromotedHumongous ulong Regions Promoted Humongous
humongousPromotedGarbage ulong: bytes Humongous Promoted Garbage Garbage memory of in place promoted humongous regions
humongousPromotedFree ulong: bytes Humongous Promoted Free Free memory of in place promoted humongous regions
regionsPromotedRegular ulong Regions Promoted Regular
regularPromotedGarbage ulong: bytes Regular Promoted Garbage Garbage memory of in place promoted regular regions
regularPromotedFree ulong: bytes Regular Promoted Free Free memory of in place promoted regular regions

StringDeduplication

default profiling startTime duration 26 27 28

Category: Java Virtual Machine / GC / Detailed

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/stringdedup/stringDedupStat.cpp:

void StringDedup::Stat::emit_statistics(bool total) const {
  if (log_is_enabled(Debug, stringdedup)) {
    log_times(total ? "Total" : "Last");
    log_statistics();
  }

  if (total) {
    // Send only JFR events about the last stats
    return;
  }

  EventStringDeduplication e;
  if (e.should_commit()) {
    e.set_starttime(_active_start);
    Ticks active_end = _active_start;
    active_end += _active_elapsed;
    e.set_endtime(active_end);

    e.set_inspected(_inspected);
    e.set_known(_known);
    e.set_shared(_known_shared);
    e.set_newStrings(_new);
    e.set_newSize(_new_bytes);

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
inspected ulong Inspected
known ulong Known
shared ulong Shared
newStrings ulong New Strings New unknown strings
newSize ulong: bytes New Size Size of new unknown strings
replaced ulong Replaced
deleted ulong Deleted
deduplicated ulong Deduplicated
deduplicatedSize ulong: bytes Deduplicated Size
skippedDead ulong Skipped Dead
skippedIncomplete ulong Skipped Incomplete
skippedShared ulong Skipped Shared
processing Tickspan Processing
tableResize Tickspan Table Resize
tableCleanup Tickspan Table Cleanup

JVM: GC: Heap

GCHeapSummary

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Heap

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

  space.set_used(summary.used());
  space.set_size(summary.size());
  return space;
}

class GCHeapSummaryEventSender : public GCHeapSummaryVisitor {
  GCWhen::Type _when;
 public:
  GCHeapSummaryEventSender(GCWhen::Type when) : _when(when) {}

  void visit(const GCHeapSummary* heap_summary) const {
    const VirtualSpaceSummary& heap_space = heap_summary->heap();

    EventGCHeapSummary e;
    if (e.should_commit()) {
      e.set_gcId(GCId::current());
      e.set_when((u1)_when);
      e.set_heapSpace(to_struct(heap_space));
      e.set_heapUsed(heap_summary->used());
      e.commit();
    }
  }

  void visit(const G1HeapSummary* g1_heap_summary) const {
    visit((GCHeapSummary*)g1_heap_summary);

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
when GCWhen When
heapSpace VirtualSpace struct Heap Space
heapUsed ulong: bytes Heap Used Bytes allocated by objects in the heap

Examples 3
Example event data values and properties
gcId uint
364
heapSpace VirtualSpace
committedEnd ulong: address
33439088640
committedSize ulong: bytes
3271557120
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
heapUsed ulong: bytes
1226021000
startTime long: millis
477733473737
when GCWhen
Before GC
Example event data values and properties
gcId uint
9
heapSpace VirtualSpace
committedEnd ulong: address
30234640384
committedSize ulong: bytes
67108864
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
heapUsed ulong: bytes
38049872
startTime long: millis
654406728
when GCWhen
Before GC
Example event data values and properties
gcId uint
1080
heapSpace VirtualSpace
committedEnd ulong: address
31046238208
committedSize ulong: bytes
878706688
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
heapUsed ulong: bytes
544686472
startTime long: millis
456530012984
when GCWhen
After GC

MetaspaceSummary

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Heap

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

  GCHeapSummaryEventSender visitor(when);
  heap_summary.accept(&visitor);
}

static JfrStructMetaspaceSizes to_struct(const MetaspaceStats& sizes) {
  JfrStructMetaspaceSizes meta_sizes;
  meta_sizes.set_committed(sizes.committed());
  meta_sizes.set_used(sizes.used());
  meta_sizes.set_reserved(sizes.reserved());
  return meta_sizes;
}

void GCTracer::send_meta_space_summary_event(GCWhen::Type when, const MetaspaceSummary& meta_space_summary) const {
  EventMetaspaceSummary e;
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_when((u1) when);
    e.set_gcThreshold(meta_space_summary.capacity_until_GC());
    e.set_metaspace(to_struct(meta_space_summary.stats())); // total stats (class + nonclass)
    e.set_dataSpace(to_struct(meta_space_summary.stats().non_class_space_stats())); // "dataspace" aka non-class space
    e.set_classSpace(to_struct(meta_space_summary.stats().class_space_stats()));
    e.commit();
  }
}

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
when GCWhen When
gcThreshold ulong: bytes GC Threshold
metaspace MetaspaceSizes struct Total
dataSpace MetaspaceSizes struct Data
classSpace MetaspaceSizes struct Class

Examples 3
Example event data values and properties
classSpace MetaspaceSizes
committed ulong: bytes
179109888
reserved ulong: bytes
1073741824
used ulong: bytes
177466784
dataSpace MetaspaceSizes
committed ulong: bytes
777715712
reserved ulong: bytes
805306368
used ulong: bytes
775829176
gcId uint
345
gcThreshold ulong: bytes
1594163200
metaspace MetaspaceSizes
committed ulong: bytes
956825600
reserved ulong: bytes
1879048192
used ulong: bytes
953295960
startTime long: millis
455203890148
when GCWhen
Before GC
Example event data values and properties
classSpace MetaspaceSizes
committed ulong: bytes
179175424
reserved ulong: bytes
1073741824
used ulong: bytes
177475112
dataSpace MetaspaceSizes
committed ulong: bytes
778371072
reserved ulong: bytes
805306368
used ulong: bytes
776513512
gcId uint
1092
gcThreshold ulong: bytes
1595932672
metaspace MetaspaceSizes
committed ulong: bytes
957546496
reserved ulong: bytes
1879048192
used ulong: bytes
953988624
startTime long: millis
459244847091
when GCWhen
After GC
Example event data values and properties
classSpace MetaspaceSizes
committed ulong: bytes
3014656
reserved ulong: bytes
1073741824
used ulong: bytes
2863120
dataSpace MetaspaceSizes
committed ulong: bytes
11993088
reserved ulong: bytes
67108864
used ulong: bytes
11893016
gcId uint
48
gcThreshold ulong: bytes
25034752
metaspace MetaspaceSizes
committed ulong: bytes
15007744
reserved ulong: bytes
1140850688
used ulong: bytes
14756136
startTime long: millis
1772712608
when GCWhen
After GC

PSHeapSummary

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Heap

Appearing in: linux_ParallelGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

  void visit(const PSHeapSummary* ps_heap_summary) const {
    visit((GCHeapSummary*)ps_heap_summary);

    const VirtualSpaceSummary& old_summary = ps_heap_summary->old();
    const SpaceSummary& old_space = ps_heap_summary->old_space();
    const VirtualSpaceSummary& young_summary = ps_heap_summary->young();
    const SpaceSummary& eden_space = ps_heap_summary->eden();
    const SpaceSummary& from_space = ps_heap_summary->from();
    const SpaceSummary& to_space = ps_heap_summary->to();

    EventPSHeapSummary e;
    if (e.should_commit()) {
      e.set_gcId(GCId::current());
      e.set_when((u1)_when);

      e.set_oldSpace(to_struct(ps_heap_summary->old()));
      e.set_oldObjectSpace(to_struct(ps_heap_summary->old_space()));
      e.set_youngSpace(to_struct(ps_heap_summary->young()));
      e.set_edenSpace(to_struct(ps_heap_summary->eden()));
      e.set_fromSpace(to_struct(ps_heap_summary->from()));
      e.set_toSpace(to_struct(ps_heap_summary->to()));
      e.commit();

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
when GCWhen When
oldSpace VirtualSpace struct Old Space
oldObjectSpace ObjectSpace struct Old Object Space
youngSpace VirtualSpace struct Young Space
edenSpace ObjectSpace struct Eden Space
fromSpace ObjectSpace struct From Space
toSpace ObjectSpace struct To Space

Examples 2
Example event data values and properties
edenSpace ObjectSpace
end ulong: address
33934016512
size ulong: bytes
970981376
start ulong: address
32963035136
used ulong: bytes
0
fromSpace ObjectSpace
end ulong: address
33996931072
size ulong: bytes
62914560
start ulong: address
33934016512
used ulong: bytes
5308448
gcId uint
364
oldObjectSpace ObjectSpace
end ulong: address
32398901248
size ulong: bytes
2231369728
start ulong: address
30167531520
used ulong: bytes
252581992
oldSpace VirtualSpace
committedEnd ulong: address
32398901248
committedSize ulong: bytes
2231369728
reservedEnd ulong: address
32963035136
reservedSize ulong: bytes
2795503616
start ulong: address
30167531520
startTime long: millis
477740633761
toSpace ObjectSpace
end ulong: address
34250686464
size ulong: bytes
60817408
start ulong: address
34189869056
used ulong: bytes
0
when GCWhen
After GC
youngSpace VirtualSpace
committedEnd ulong: address
34250686464
committedSize ulong: bytes
1287651328
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
1396703232
start ulong: address
32963035136
Example event data values and properties
edenSpace ObjectSpace
end ulong: address
33478934528
size ulong: bytes
515899392
start ulong: address
32963035136
used ulong: bytes
0
fromSpace ObjectSpace
end ulong: address
33491517440
size ulong: bytes
6291456
start ulong: address
33485225984
used ulong: bytes
0
gcId uint
37
oldObjectSpace ObjectSpace
end ulong: address
30343692288
size ulong: bytes
176160768
start ulong: address
30167531520
used ulong: bytes
6550176
oldSpace VirtualSpace
committedEnd ulong: address
30343692288
committedSize ulong: bytes
176160768
reservedEnd ulong: address
32963035136
reservedSize ulong: bytes
2795503616
start ulong: address
30167531520
startTime long: millis
1494593114
toSpace ObjectSpace
end ulong: address
33485225984
size ulong: bytes
6291456
start ulong: address
33478934528
used ulong: bytes
0
when GCWhen
After GC
youngSpace VirtualSpace
committedEnd ulong: address
33491517440
committedSize ulong: bytes
528482304
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
1396703232
start ulong: address
32963035136

G1HeapSummary

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Heap

Appearing in: graalvm_linux_G1GC, linux_G1GC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

    EventGCHeapSummary e;
    if (e.should_commit()) {
      e.set_gcId(GCId::current());
      e.set_when((u1)_when);
      e.set_heapSpace(to_struct(heap_space));
      e.set_heapUsed(heap_summary->used());
      e.commit();
    }
  }

  void visit(const G1HeapSummary* g1_heap_summary) const {
    visit((GCHeapSummary*)g1_heap_summary);

    EventG1HeapSummary e;
    if (e.should_commit()) {
      e.set_gcId(GCId::current());
      e.set_when((u1)_when);
      e.set_edenUsedSize(g1_heap_summary->edenUsed());
      e.set_edenTotalSize(g1_heap_summary->edenCapacity());
      e.set_survivorUsedSize(g1_heap_summary->survivorUsed());
      e.set_oldGenUsedSize(g1_heap_summary->oldGenUsed());
      e.set_numberOfRegions(g1_heap_summary->numberOfRegions());
      e.commit();
    }
  }

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
when GCWhen When
edenUsedSize ulong: bytes Eden Used Size
edenTotalSize ulong: bytes Eden Total Size
survivorUsedSize ulong: bytes Survivor Used Size
oldGenUsedSize ulong: bytes 21+ Old Generation Used Size
numberOfRegions uint Number of Regions

Examples 3
Example event data values and properties
edenTotalSize ulong: bytes
520093696
edenUsedSize ulong: bytes
165675008
gcId uint
1094
numberOfRegions uint
414
oldGenUsedSize ulong: bytes
310982104
startTime long: millis
460290748472
survivorUsedSize ulong: bytes
0
when GCWhen
Before GC
Example event data values and properties
edenTotalSize ulong: bytes
10485760
edenUsedSize ulong: bytes
8388608
gcId uint
36
numberOfRegions uint
14
oldGenUsedSize ulong: bytes
9156976
startTime long: millis
1625605529
survivorUsedSize ulong: bytes
0
when GCWhen
Before GC
Example event data values and properties
edenTotalSize ulong: bytes
561927672
edenUsedSize ulong: bytes
0
gcId uint
1222
numberOfRegions uint
447
oldGenUsedSize ulong: bytes
276176448
startTime long: millis
488305600480
survivorUsedSize ulong: bytes
109064
when GCWhen
Before GC

JVM: GC: Metaspace

MetaspaceGCThreshold

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Metaspace

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/memory/metaspaceTracer.cpp:

void MetaspaceTracer::report_gc_threshold(size_t old_val,
                                          size_t new_val,
                                          MetaspaceGCThresholdUpdater::Type updater) const {
  EventMetaspaceGCThreshold event;
  if (event.should_commit()) {
    event.set_oldValue(old_val);
    event.set_newValue(new_val);
    event.set_updater((u1)updater);
    event.commit();
  }
}

void MetaspaceTracer::report_metaspace_allocation_failure(ClassLoaderData *cld,
                                                          size_t word_size,
                                                          MetaspaceObj::Type objtype,
                                                          Metaspace::MetadataType mdtype) const {
  send_allocation_failure_event<EventMetaspaceAllocationFailure>(cld, word_size, objtype, mdtype);
}

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
oldValue ulong: bytes Old Value
newValue ulong: bytes New Value
updater GCThresholdUpdater Updater

Examples 3
Example event data values and properties
newValue ulong: bytes
1596915712
oldValue ulong: bytes
1596063744
startTime long: millis
475492725765
updater GCThresholdUpdater
compute_new_size
Example event data values and properties
newValue ulong: bytes
1674444800
oldValue ulong: bytes
1662320640
startTime long: millis
496676414596
updater GCThresholdUpdater
compute_new_size
Example event data values and properties
newValue ulong: bytes
25362432
oldValue ulong: bytes
25034752
startTime long: millis
8995617210
updater GCThresholdUpdater
compute_new_size

MetaspaceAllocationFailure

default profiling startTime stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Metaspace

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/memory/metaspaceTracer.cpp:

  EventMetaspaceGCThreshold event;
  if (event.should_commit()) {
    event.set_oldValue(old_val);
    event.set_newValue(new_val);
    event.set_updater((u1)updater);
    event.commit();
  }
}

void MetaspaceTracer::report_metaspace_allocation_failure(ClassLoaderData *cld,
                                                          size_t word_size,
                                                          MetaspaceObj::Type objtype,
                                                          Metaspace::MetadataType mdtype) const {
  send_allocation_failure_event<EventMetaspaceAllocationFailure>(cld, word_size, objtype, mdtype);
}

void MetaspaceTracer::report_metadata_oom(ClassLoaderData *cld,
                                         size_t word_size,
                                         MetaspaceObj::Type objtype,
                                         Metaspace::MetadataType mdtype) const {
  send_allocation_failure_event<EventMetaspaceOOM>(cld, word_size, objtype, mdtype);
}

template <typename E>
void MetaspaceTracer::send_allocation_failure_event(ClassLoaderData *cld,

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default true true
profiling true true

Event fields with their types and descriptions
Field Type Description
classLoader ClassLoader Class Loader
hiddenClassLoader boolean 15+ Hidden Class Loader
size ulong: bytes Size
metadataType MetadataType Metadata Type
metaspaceObjectType MetaspaceObjectType Metaspace Object Type

MetaspaceOOM

default profiling startTime stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Metaspace

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/memory/metaspaceTracer.cpp:

void MetaspaceTracer::report_metaspace_allocation_failure(ClassLoaderData *cld,
                                                          size_t word_size,
                                                          MetaspaceObj::Type objtype,
                                                          Metaspace::MetadataType mdtype) const {
  send_allocation_failure_event<EventMetaspaceAllocationFailure>(cld, word_size, objtype, mdtype);
}

void MetaspaceTracer::report_metadata_oom(ClassLoaderData *cld,
                                         size_t word_size,
                                         MetaspaceObj::Type objtype,
                                         Metaspace::MetadataType mdtype) const {
  send_allocation_failure_event<EventMetaspaceOOM>(cld, word_size, objtype, mdtype);
}

template <typename E>
void MetaspaceTracer::send_allocation_failure_event(ClassLoaderData *cld,
                                                    size_t word_size,
                                                    MetaspaceObj::Type objtype,
                                                    Metaspace::MetadataType mdtype) const {
  E event;
  if (event.should_commit()) {
    event.set_classLoader(cld);
    event.set_hiddenClassLoader(cld->has_class_mirror_holder());

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default true true
profiling true true

Event fields with their types and descriptions
Field Type Description
classLoader ClassLoader Class Loader
hiddenClassLoader boolean 15+ Hidden Class Loader
size ulong: bytes Size
metadataType MetadataType Metadata Type
metaspaceObjectType MetaspaceObjectType Metaspace Object Type

MetaspaceChunkFreeListSummary

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Metaspace

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

void GCTracer::send_reference_stats_event(ReferenceType type, size_t count) const {
  EventGCReferenceStatistics e;
  if (e.should_commit()) {
      e.set_gcId(GCId::current());
      e.set_type((u1)type);
      e.set_count(count);
      e.commit();
  }
}

void GCTracer::send_metaspace_chunk_free_list_summary(GCWhen::Type when, Metaspace::MetadataType mdtype,
                                                      const MetaspaceChunkFreeListSummary& summary) const {
  EventMetaspaceChunkFreeListSummary e;
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_when(when);
    e.set_metadataType(mdtype);

    e.set_specializedChunks(summary.num_specialized_chunks());
    e.set_specializedChunksTotalSize(summary.specialized_chunks_size_in_bytes());

    e.set_smallChunks(summary.num_small_chunks());
    e.set_smallChunksTotalSize(summary.small_chunks_size_in_bytes());

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
when GCWhen When
metadataType MetadataType Metadata Type
specializedChunks ulong Specialized Chunks
specializedChunksTotalSize ulong: bytes Specialized Chunks Total Size
smallChunks ulong Small Chunks
smallChunksTotalSize ulong: bytes Small Chunks Total Size
mediumChunks ulong Medium Chunks
mediumChunksTotalSize ulong: bytes Medium Chunks Total Size
humongousChunks ulong Humongous Chunks
humongousChunksTotalSize ulong: bytes Humongous Chunks Total Size

Examples 3
Example event data values and properties
gcId uint
8
humongousChunks ulong
0
humongousChunksTotalSize ulong: bytes
0
mediumChunks ulong
0
mediumChunksTotalSize ulong: bytes
0
metadataType MetadataType
Class
smallChunks ulong
0
smallChunksTotalSize ulong: bytes
0
specializedChunks ulong
0
specializedChunksTotalSize ulong: bytes
0
startTime long: millis
637025215
when GCWhen
Before GC
Example event data values and properties
gcId uint
341
humongousChunks ulong
0
humongousChunksTotalSize ulong: bytes
0
mediumChunks ulong
0
mediumChunksTotalSize ulong: bytes
0
metadataType MetadataType
Class
smallChunks ulong
0
smallChunksTotalSize ulong: bytes
0
specializedChunks ulong
0
specializedChunksTotalSize ulong: bytes
0
startTime long: millis
450822658631
when GCWhen
After GC
Example event data values and properties
gcId uint
1084
humongousChunks ulong
0
humongousChunksTotalSize ulong: bytes
0
mediumChunks ulong
0
mediumChunksTotalSize ulong: bytes
0
metadataType MetadataType
Class
smallChunks ulong
0
smallChunksTotalSize ulong: bytes
0
specializedChunks ulong
0
specializedChunksTotalSize ulong: bytes
0
startTime long: millis
457145087230
when GCWhen
Before GC

JVM: GC: Phases

GCPhasePause

default profiling startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

    e.set_gcThreshold(meta_space_summary.capacity_until_GC());
    e.set_metaspace(to_struct(meta_space_summary.stats())); // total stats (class + nonclass)
    e.set_dataSpace(to_struct(meta_space_summary.stats().non_class_space_stats())); // "dataspace" aka non-class space
    e.set_classSpace(to_struct(meta_space_summary.stats().class_space_stats()));
    e.commit();
  }
}

class PhaseSender : public PhaseVisitor {
  void visit_pause(GCPhase* phase) {
    assert(phase->level() < PhasesStack::PHASE_LEVELS, "Need more event types for PausePhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhasePause>(phase); break;
      case 1: send_phase<EventGCPhasePauseLevel1>(phase); break;
      case 2: send_phase<EventGCPhasePauseLevel2>(phase); break;
      case 3: send_phase<EventGCPhasePauseLevel3>(phase); break;
      case 4: send_phase<EventGCPhasePauseLevel4>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 3, "There are only three levels for ConcurrentPhase");

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
Example event data values and properties
gcId uint
72
name string
GC Pause
startTime long: millis
2001509579
Example event data values and properties
gcId uint
377
name string
GC Pause
startTime long: millis
498757429533
Example event data values and properties
gcId uint
1142
name string
GC Pause
startTime long: millis
473907816610

GCPhasePauseLevel1

default profiling startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

Appearing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Missing in: linux_ZGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

    e.set_metaspace(to_struct(meta_space_summary.stats())); // total stats (class + nonclass)
    e.set_dataSpace(to_struct(meta_space_summary.stats().non_class_space_stats())); // "dataspace" aka non-class space
    e.set_classSpace(to_struct(meta_space_summary.stats().class_space_stats()));
    e.commit();
  }
}

class PhaseSender : public PhaseVisitor {
  void visit_pause(GCPhase* phase) {
    assert(phase->level() < PhasesStack::PHASE_LEVELS, "Need more event types for PausePhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhasePause>(phase); break;
      case 1: send_phase<EventGCPhasePauseLevel1>(phase); break;
      case 2: send_phase<EventGCPhasePauseLevel2>(phase); break;
      case 3: send_phase<EventGCPhasePauseLevel3>(phase); break;
      case 4: send_phase<EventGCPhasePauseLevel4>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 3, "There are only three levels for ConcurrentPhase");

    switch (phase->level()) {

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
Example event data values and properties
gcId uint
5
name string
Notify PhantomReferences
startTime long: millis
575404007
Example event data values and properties
gcId uint
341
name string
Forward
startTime long: millis
450756620311
Example event data values and properties
gcId uint
1065
name string
Notify and keep alive finalizable
startTime long: millis
453045913412

GCPhasePauseLevel2

default profiling startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

Appearing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: linux_ShenandoahGC, linux_ZGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

    e.set_dataSpace(to_struct(meta_space_summary.stats().non_class_space_stats())); // "dataspace" aka non-class space
    e.set_classSpace(to_struct(meta_space_summary.stats().class_space_stats()));
    e.commit();
  }
}

class PhaseSender : public PhaseVisitor {
  void visit_pause(GCPhase* phase) {
    assert(phase->level() < PhasesStack::PHASE_LEVELS, "Need more event types for PausePhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhasePause>(phase); break;
      case 1: send_phase<EventGCPhasePauseLevel1>(phase); break;
      case 2: send_phase<EventGCPhasePauseLevel2>(phase); break;
      case 3: send_phase<EventGCPhasePauseLevel3>(phase); break;
      case 4: send_phase<EventGCPhasePauseLevel4>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 3, "There are only three levels for ConcurrentPhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhaseConcurrent>(phase); break;

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
Example event data values and properties
gcId uint
1098
name string
Phase 1: Weak Processing
startTime long: millis
461630907471
Example event data values and properties
gcId uint
341
name string
Reference Processing
startTime long: millis
450618275086
Example event data values and properties
gcId uint
34
name string
Phase 2: Determine work lists
startTime long: millis
1597382364

GCPhasePauseLevel3

startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

    e.set_classSpace(to_struct(meta_space_summary.stats().class_space_stats()));
    e.commit();
  }
}

class PhaseSender : public PhaseVisitor {
  void visit_pause(GCPhase* phase) {
    assert(phase->level() < PhasesStack::PHASE_LEVELS, "Need more event types for PausePhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhasePause>(phase); break;
      case 1: send_phase<EventGCPhasePauseLevel1>(phase); break;
      case 2: send_phase<EventGCPhasePauseLevel2>(phase); break;
      case 3: send_phase<EventGCPhasePauseLevel3>(phase); break;
      case 4: send_phase<EventGCPhasePauseLevel4>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 3, "There are only three levels for ConcurrentPhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhaseConcurrent>(phase); break;
      case 1: send_phase<EventGCPhaseConcurrentLevel1>(phase); break;

Event configuration settings across JFR profiles
Configuration enabled threshold
default false 0 ms
profiling false 0 ms

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
Example event data values and properties
gcId uint
1085
name string
Notify PhantomReferences
startTime long: millis
457233210473
Example event data values and properties
gcId uint
0
name string
Free Code Blobs
startTime long: millis
368968406
Example event data values and properties
gcId uint
344
name string
Notify and keep alive finalizable
startTime long: millis
454191804908

GCPhasePauseLevel4

startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC

Missing in: graalvm_linux_native, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

    e.commit();
  }
}

class PhaseSender : public PhaseVisitor {
  void visit_pause(GCPhase* phase) {
    assert(phase->level() < PhasesStack::PHASE_LEVELS, "Need more event types for PausePhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhasePause>(phase); break;
      case 1: send_phase<EventGCPhasePauseLevel1>(phase); break;
      case 2: send_phase<EventGCPhasePauseLevel2>(phase); break;
      case 3: send_phase<EventGCPhasePauseLevel3>(phase); break;
      case 4: send_phase<EventGCPhasePauseLevel4>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 3, "There are only three levels for ConcurrentPhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhaseConcurrent>(phase); break;
      case 1: send_phase<EventGCPhaseConcurrentLevel1>(phase); break;
      case 2: send_phase<EventGCPhaseConcurrentLevel2>(phase); break;

Event configuration settings across JFR profiles
Configuration enabled threshold
default false 0 ms
profiling false 0 ms

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
Example event data values and properties
gcId uint
349
name string
Balance queues
startTime long: millis
459302809308
Example event data values and properties
gcId uint
1133
name string
Balance queues
startTime long: millis
471067372631
Example event data values and properties
gcId uint
1183
name string
Balance queues
startTime long: millis
479644594685

GCPhaseConcurrent

default profiling startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shenandoah/shenandoahUtils.hpp:

class ShenandoahWorkerSession : public StackObj {
protected:
  ShenandoahWorkerSession(uint worker_id);
public:
  static inline uint worker_id() {
    return WorkerThread::worker_id();
  }
};

class ShenandoahConcurrentWorkerSession : public ShenandoahWorkerSession {
private:
  EventGCPhaseConcurrent _event;

public:
  ShenandoahConcurrentWorkerSession(uint worker_id) : ShenandoahWorkerSession(worker_id) { }
  ~ShenandoahConcurrentWorkerSession();
};

class ShenandoahParallelWorkerSession : public ShenandoahWorkerSession {
private:
  EventGCPhaseParallel _event;

public:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

      case 0: send_phase<EventGCPhasePause>(phase); break;
      case 1: send_phase<EventGCPhasePauseLevel1>(phase); break;
      case 2: send_phase<EventGCPhasePauseLevel2>(phase); break;
      case 3: send_phase<EventGCPhasePauseLevel3>(phase); break;
      case 4: send_phase<EventGCPhasePauseLevel4>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 3, "There are only three levels for ConcurrentPhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhaseConcurrent>(phase); break;
      case 1: send_phase<EventGCPhaseConcurrentLevel1>(phase); break;
      case 2: send_phase<EventGCPhaseConcurrentLevel2>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

 public:
  template<typename T>
  void send_phase(GCPhase* phase) {
    T event(UNTIMED);
    if (event.should_commit()) {

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
Example event data values and properties
gcId uint
380
name string
Concurrent Mark From Roots
startTime long: millis
5594470411
Example event data values and properties
gcId uint
280
name string
Concurrent Strong Roots
startTime long: millis
553576769496
Example event data values and properties
gcId uint
1077
name string
Concurrent Clear Claimed Marks
startTime long: millis
455916751714

GCPhaseConcurrentLevel1

default profiling startTime duration eventThread 15 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

      case 1: send_phase<EventGCPhasePauseLevel1>(phase); break;
      case 2: send_phase<EventGCPhasePauseLevel2>(phase); break;
      case 3: send_phase<EventGCPhasePauseLevel3>(phase); break;
      case 4: send_phase<EventGCPhasePauseLevel4>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 3, "There are only three levels for ConcurrentPhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhaseConcurrent>(phase); break;
      case 1: send_phase<EventGCPhaseConcurrentLevel1>(phase); break;
      case 2: send_phase<EventGCPhaseConcurrentLevel2>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

 public:
  template<typename T>
  void send_phase(GCPhase* phase) {
    T event(UNTIMED);
    if (event.should_commit()) {
      event.set_gcId(GCId::current());

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
Example event data values and properties
gcId uint
301
name string
Trigger cleanups
startTime long: millis
588542928616
Example event data values and properties
gcId uint
1095
name string
Preclean WeakReferences
startTime long: millis
460704950578
Example event data values and properties
gcId uint
29
name string
Preclean SoftReferences
startTime long: millis
1520148712

GCPhaseConcurrentLevel2

default profiling startTime duration eventThread 21 25 27 28

Category: Java Virtual Machine / GC / Phases

Appearing in: linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

      case 2: send_phase<EventGCPhasePauseLevel2>(phase); break;
      case 3: send_phase<EventGCPhasePauseLevel3>(phase); break;
      case 4: send_phase<EventGCPhasePauseLevel4>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 3, "There are only three levels for ConcurrentPhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhaseConcurrent>(phase); break;
      case 1: send_phase<EventGCPhaseConcurrentLevel1>(phase); break;
      case 2: send_phase<EventGCPhaseConcurrentLevel2>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

 public:
  template<typename T>
  void send_phase(GCPhase* phase) {
    T event(UNTIMED);
    if (event.should_commit()) {
      event.set_gcId(GCId::current());
      event.set_name(phase->name());

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
name string Name

Examples 2
Example event data values and properties
gcId uint
269
name string
Trigger cleanups
startTime long: millis
661412077410
Example event data values and properties
gcId uint
12
name string
Trigger cleanups
startTime long: millis
1940604246

GCPhaseParallel

default profiling startTime duration eventThread 12 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ShenandoahGC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC, linux_ZGC

GC phases for parallel workers

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/g1/g1YoungCollector.cpp:

  G1CollectedHeap*              _g1h;
  G1ParScanThreadState*         _par_scan_state;
  G1ScannerTasksQueueSet*       _queues;
  TaskTerminator*               _terminator;
  G1GCPhaseTimes::GCParPhases   _phase;

  G1ParScanThreadState*   par_scan_state() { return _par_scan_state; }
  G1ScannerTasksQueueSet* queues()         { return _queues; }
  TaskTerminator*         terminator()     { return _terminator; }

  inline bool offer_termination() {
    EventGCPhaseParallel event;
    G1ParScanThreadState* const pss = par_scan_state();
    start_term_time();
    const bool res = (terminator() == nullptr) ? true : terminator()->offer_termination();
    end_term_time();
    event.commit(GCId::current(), pss->worker_id(), G1GCPhaseTimes::phase_name(G1GCPhaseTimes::Termination));
    return res;
  }

public:
  G1ParEvacuateFollowersClosure(G1CollectedHeap* g1h,
                                G1ParScanThreadState* par_scan_state,
                                G1ScannerTasksQueueSet* queues,
                                TaskTerminator* terminator,
                                G1GCPhaseTimes::GCParPhases phase)
    : _start_term(0.0), _term_time(0.0), _term_attempts(0),
      _g1h(g1h), _par_scan_state(par_scan_state),
      _queues(queues), _terminator(terminator), _phase(phase) {}

  void do_void() {
    EventGCPhaseParallel event;
    G1ParScanThreadState* const pss = par_scan_state();
    pss->trim_queue();
    event.commit(GCId::current(), pss->worker_id(), G1GCPhaseTimes::phase_name(_phase));
    do {
      EventGCPhaseParallel event;
      pss->steal_and_trim_queue(queues());
      event.commit(GCId::current(), pss->worker_id(), G1GCPhaseTimes::phase_name(_phase));
    } while (!offer_termination());
  }

  double term_time() const { return _term_time; }
  size_t term_attempts() const { return _term_attempts; }
};

class G1EvacuateRegionsBaseTask : public WorkerTask {

src/hotspot/share/gc/shenandoah/shenandoahPhaseTimings.hpp:

  void print_cycle_on(outputStream* out) const;
  void print_global_on(outputStream* out) const;
};

class ShenandoahWorkerTimingsTracker : public StackObj {
private:
  ShenandoahPhaseTimings*          const _timings;
  ShenandoahPhaseTimings::Phase    const _phase;
  ShenandoahPhaseTimings::WorkerPhase const _worker_phase;
  uint const _worker_id;

  double _start_time;
  EventGCPhaseParallel _event;
public:
  ShenandoahWorkerTimingsTracker(ShenandoahPhaseTimings::Phase phase,
                                 ShenandoahPhaseTimings::WorkerPhase worker_phase,
                                 uint worker_id,
                                 bool cumulative = false);
  ~ShenandoahWorkerTimingsTracker();
};

#endif // SHARE_GC_SHENANDOAH_SHENANDOAHPHASETIMINGS_HPP

src/hotspot/share/gc/shenandoah/shenandoahUtils.hpp:

class ShenandoahConcurrentWorkerSession : public ShenandoahWorkerSession {
private:
  EventGCPhaseConcurrent _event;

public:
  ShenandoahConcurrentWorkerSession(uint worker_id) : ShenandoahWorkerSession(worker_id) { }
  ~ShenandoahConcurrentWorkerSession();
};

class ShenandoahParallelWorkerSession : public ShenandoahWorkerSession {
private:
  EventGCPhaseParallel _event;

public:
  ShenandoahParallelWorkerSession(uint worker_id) : ShenandoahWorkerSession(worker_id) { }
  ~ShenandoahParallelWorkerSession();
};

// Regions cannot be uncommitted when concurrent reset is zeroing out the bitmaps.
// This CADR class enforces this by forbidding region uncommits while it is in scope.
class ShenandoahNoUncommitMark : public StackObj {
  ShenandoahHeap* const _heap;
public:

src/hotspot/share/gc/g1/g1GCParPhaseTimesTracker.hpp:

#ifndef SHARE_GC_G1_G1GCPARPHASETIMESTRACKER_HPP
#define SHARE_GC_G1_G1GCPARPHASETIMESTRACKER_HPP

#include "gc/g1/g1GCPhaseTimes.hpp"
#include "jfr/jfrEvents.hpp"
#include "utilities/ticks.hpp"

class G1GCParPhaseTimesTracker : public CHeapObj<mtGC> {
protected:
  Ticks _start_time;
  G1GCPhaseTimes::GCParPhases _phase;
  G1GCPhaseTimes* _phase_times;
  uint _worker_id;
  EventGCPhaseParallel _event;
  bool _allow_multiple_record;

public:
  G1GCParPhaseTimesTracker(G1GCPhaseTimes* phase_times, G1GCPhaseTimes::GCParPhases phase, uint worker_id, bool allow_multiple_record = false);
  virtual ~G1GCParPhaseTimesTracker();
};

class G1EvacPhaseTimesTracker : public G1GCParPhaseTimesTracker {
  Tickspan _total_time;
  Tickspan _trim_time;

src/hotspot/share/gc/g1/g1YoungGCPostEvacuateTasks.cpp:

  void account_evacuated_region(G1HeapRegion* r) {
    size_t used = r->used();
    assert(used > 0, "region %u %s zero used", r->hrm_index(), r->get_short_type_str());
    _before_used_bytes += used;
    _regions_freed += 1;
  }
};

// Closure applied to all regions in the collection set.
class FreeCSetClosure : public G1HeapRegionClosure {
  // Helper to send JFR events for regions.
  class JFREventForRegion {
    EventGCPhaseParallel _event;

  public:
    JFREventForRegion(G1HeapRegion* region, uint worker_id) : _event() {
      _event.set_gcId(GCId::current());
      _event.set_gcWorkerId(worker_id);
      if (region->is_young()) {
        _event.set_name(G1GCPhaseTimes::phase_name(G1GCPhaseTimes::YoungFreeCSet));
      } else {
        _event.set_name(G1GCPhaseTimes::phase_name(G1GCPhaseTimes::NonYoungFreeCSet));
      }
    }

src/hotspot/share/gc/g1/g1RemSet.cpp:

  size_t cards_scanned_empty() const { return _cards_empty; }
  size_t cards_scanned() const { return _cards_scanned; }
  size_t blocks_scanned() const { return _blocks_scanned; }
  size_t chunks_claimed() const { return _chunks_claimed; }
  size_t heap_roots_found() const { return _heap_roots_found; }
};

void G1RemSet::scan_heap_roots(G1ParScanThreadState* pss,
                               uint worker_id,
                               G1GCPhaseTimes::GCParPhases scan_phase,
                               G1GCPhaseTimes::GCParPhases objcopy_phase,
                               bool remember_already_scanned_cards) {
  EventGCPhaseParallel event;
  G1ScanHRForRegionClosure cl(_scan_state, pss, worker_id, scan_phase, remember_already_scanned_cards);
  _scan_state->iterate_dirty_regions_from(&cl, worker_id);

  event.commit(GCId::current(), worker_id, G1GCPhaseTimes::phase_name(scan_phase));

  G1GCPhaseTimes* p = _g1p->phase_times();

  p->record_or_add_time_secs(objcopy_phase, worker_id, cl.rem_set_trim_partially_time().seconds());

  p->record_or_add_time_secs(scan_phase, worker_id, cl.rem_set_root_scan_time().seconds());

src/hotspot/share/gc/g1/g1RemSet.cpp:

    r->code_roots_do(&cl);
    _code_roots_scanned += cl.count();
    return false;
  }

  size_t code_roots_scanned() const { return _code_roots_scanned; }
};

void G1RemSet::scan_collection_set_code_roots(G1ParScanThreadState* pss,
                                              uint worker_id,
                                              G1GCPhaseTimes::GCParPhases coderoots_phase,
                                              G1GCPhaseTimes::GCParPhases objcopy_phase) {
  EventGCPhaseParallel event;
  Tickspan code_root_scan_time;
  Tickspan code_root_trim_partially_time;

  G1GCPhaseTimes* p = _g1h->phase_times();
  {
    G1EvacPhaseWithTrimTimeTracker timer(pss, code_root_scan_time, code_root_trim_partially_time);

    G1ScanCodeRootsClosure cl(_scan_state, pss, worker_id);
    // Code roots work distribution occurs inside the iteration method. So scan all collection
    // set regions for all threads.

src/hotspot/share/gc/g1/g1RemSet.cpp:

  size_t opt_roots_scanned() const { return _opt_roots_scanned; }
  size_t opt_refs_scanned() const { return _opt_refs_scanned; }
  size_t opt_refs_memory_used() const { return _opt_refs_memory_used; }
};

void G1RemSet::scan_collection_set_optional_roots(G1ParScanThreadState* pss,
                                                  uint worker_id,
                                                  G1GCPhaseTimes::GCParPhases scan_phase,
                                                  G1GCPhaseTimes::GCParPhases objcopy_phase) {
  assert(scan_phase == G1GCPhaseTimes::OptScanHR, "must be");

  EventGCPhaseParallel event;

  Tickspan rem_set_opt_root_scan_time;
  Tickspan rem_set_opt_trim_partially_time;
  G1EvacPhaseWithTrimTimeTracker timer(pss, rem_set_opt_root_scan_time, rem_set_opt_trim_partially_time);

  G1GCPhaseTimes* p = _g1h->phase_times();

  G1ScanOptionalRemSetRootsClosure cl(pss, worker_id, scan_phase);
  // The individual references for the optional remembered set are per-worker, so every worker
  // always need to scan all regions (no claimer).

src/hotspot/share/gc/g1/g1HeapRegionManager.cpp:

      _worker_freelists[worker].~G1FreeRegionList();
    }
    FREE_C_HEAP_ARRAY(_worker_freelists);
  }

  G1FreeRegionList* worker_freelist(uint worker) {
    return &_worker_freelists[worker];
  }

  // Each worker creates a free list for a chunk of the heap. The chunks won't
  // be overlapping so we don't need to do any claiming.
  void work(uint worker_id) {
    Ticks start_time = Ticks::now();
    EventGCPhaseParallel event;

    uint start = worker_id * _worker_chunk_size;
    uint end = MIN2(start + _worker_chunk_size, _hrm->max_num_regions());

    // If start is outside the heap, this worker has nothing to do.
    if (start > end) {
      return;
    }

    G1FreeRegionList* free_list = worker_freelist(worker_id);
    for (uint i = start; i < end; i++) {

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
gcWorkerId uint GC Worker Identifier
name string Name

Examples 3
Example event data values and properties
gcId uint
2
gcWorkerId uint
1
name string
CLDGRoots
startTime long: millis
566486871
Example event data values and properties
gcId uint
1065
gcWorkerId uint
0
name string
NonJavaThreadFlushLogs
startTime long: millis
453042105488
Example event data values and properties
gcId uint
284
gcWorkerId uint
0
name string
Finish Mark
startTime long: millis
559343622233

JVM: GC: Reference

GCReferenceStatistics

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Reference

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Total count of processed references during GC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/gcTraceSend.cpp:

void GCTracer::send_cpu_time_event(double user_time, double system_time, double real_time) const {
  EventGCCPUTime e;
  if (e.should_commit()) {
      e.set_gcId(GCId::current());
      e.set_userTime((size_t)(user_time * NANOUNITS));
      e.set_systemTime((size_t)(system_time * NANOUNITS));
      e.set_realTime((size_t)(real_time * NANOUNITS));
      e.commit();
  }
}

void GCTracer::send_reference_stats_event(ReferenceType type, size_t count) const {
  EventGCReferenceStatistics e;
  if (e.should_commit()) {
      e.set_gcId(GCId::current());
      e.set_type((u1)type);
      e.set_count(count);
      e.commit();
  }
}

void GCTracer::send_metaspace_chunk_free_list_summary(GCWhen::Type when, Metaspace::MetadataType mdtype,
                                                      const MetaspaceChunkFreeListSummary& summary) const {
  EventMetaspaceChunkFreeListSummary e;

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
type ReferenceType Type
count ulong Total Count

Examples 3
Example event data values and properties
count ulong
316
gcId uint
1085
startTime long: millis
457233222255
type ReferenceType
Final reference
Example event data values and properties
count ulong
302
gcId uint
21
startTime long: millis
1266092935
type ReferenceType
Weak reference
Example event data values and properties
count ulong
0
gcId uint
362
startTime long: millis
477026750914
type ReferenceType
Phantom reference

JVM: Heap

GCHeapMemoryUsage

default profiling startTime every chunk 21 25 27 28

Category: Java Virtual Machine / Heap

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

TRACE_REQUEST_FUNC(JavaThreadStatistics) {
  EventJavaThreadStatistics event;
  event.set_activeCount(ThreadService::get_live_thread_count());
  event.set_daemonCount(ThreadService::get_daemon_thread_count());
  event.set_accumulatedCount(ThreadService::get_total_thread_count());
  event.set_peakCount(ThreadService::get_peak_thread_count());
  event.commit();
}

TRACE_REQUEST_FUNC(GCHeapMemoryUsage) {
  MemoryUsage usage = Universe::heap()->memory_usage();
  EventGCHeapMemoryUsage event(UNTIMED);
  event.set_used(usage.used());
  event.set_committed(usage.committed());
  event.set_max(usage.max_size());
  event.set_starttime(timestamp());
  event.set_endtime(timestamp());
  event.commit();
}

TRACE_REQUEST_FUNC(GCHeapMemoryPoolUsage) {
  ResourceMark mark;
  GrowableArray<MemoryPool*> pools = Universe::heap()->memory_pools();

Event configuration settings across JFR profiles
Configuration enabled period
default true everyChunk
profiling true everyChunk

Event fields with their types and descriptions
Field Type Description
used ulong: bytes Heap Used Bytes allocated for storing objects on the heap
committed ulong: bytes Heap Committed Bytes committed for storing objects on the heap
max ulong: bytes Heap Max Max size for the heap

Examples 3
Example event data values and properties
committed ulong: bytes
3403677696
max ulong: bytes
3726639104
startTime long: millis
462448331960
used ulong: bytes
268542864
Example event data values and properties
committed ulong: bytes
880803840
max ulong: bytes
4192206848
startTime long: millis
461539263349
used ulong: bytes
563699688
Example event data values and properties
committed ulong: bytes
29360128
max ulong: bytes
4192206848
startTime long: millis
23227569076
used ulong: bytes
14805232

GCHeapMemoryPoolUsage

default profiling startTime every chunk 21 25 27 28

Category: Java Virtual Machine / Heap

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  event.set_max(usage.max_size());
  event.set_starttime(timestamp());
  event.set_endtime(timestamp());
  event.commit();
}

TRACE_REQUEST_FUNC(GCHeapMemoryPoolUsage) {
  ResourceMark mark;
  GrowableArray<MemoryPool*> pools = Universe::heap()->memory_pools();
  for (int i = 0; i < pools.length(); i++) {
    MemoryPool* pool = pools.at(i);
    if (pool->is_heap()) {
      MemoryUsage usage = pool->get_memory_usage();
      EventGCHeapMemoryPoolUsage event(UNTIMED);
      event.set_name(pool->name());
      event.set_used(usage.used());
      event.set_committed(usage.committed());
      event.set_max(usage.max_size());
      event.set_starttime(timestamp());
      event.set_endtime(timestamp());
      event.commit();
    }
  }
}

Event configuration settings across JFR profiles
Configuration enabled period
default true everyChunk
profiling true everyChunk

Event fields with their types and descriptions
Field Type Description
name string Name GC Heap Memory Pool Name
used ulong: bytes GC Heap Memory Pool Used Bytes used for storing objects in this memory pool
committed ulong: bytes GC Heap Memory Pool Committed Bytes committed for storing objects in this memory pool
max ulong: bytes GC Heap Memory Pool Max Max size for storing objects in this memory pool

Examples 3
Example event data values and properties
committed ulong: bytes
2097152
max ulong: bytes
-1
name string
G1 Survivor Space
startTime long: millis
479556436232
used ulong: bytes
574552
Example event data values and properties
committed ulong: bytes
20971520
max ulong: bytes
4192206848
name string
G1 Old Gen
startTime long: millis
15622960748
used ulong: bytes
7815952
Example event data values and properties
committed ulong: bytes
2231369728
max ulong: bytes
2795503616
name string
PS Old Gen
startTime long: millis
454119343746
used ulong: bytes
246023208

JVM: Internal

Duration

internal startTime duration eventThread 18 21 25 27 28

Category: Java Virtual Machine / Internal

Instant

internal startTime eventThread 18 21 25 27 28

Category: Java Virtual Machine / Internal

Value

internal startTime eventThread 18 21 25 27 28

Category: Java Virtual Machine / Internal

Event fields with their types and descriptions
Field Type Description
value ulong Value

Text

internal startTime eventThread 18 21 25 27 28

Category: Java Virtual Machine / Internal

Event fields with their types and descriptions
Field Type Description
text string Text

JVM: Memory

ResidentSetSize

default profiling startTime duration every chunk 21 25 27 28

Category: Java Virtual Machine / Memory

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Resident set size of the process

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/os/linux/os_linux.cpp:

  if (!print_model_name_and_flags(st, buf, buflen)) {
    _print_ascii_file_h("/proc/cpuinfo", "/proc/cpuinfo", st, false);
  }
  st->cr();
  print_sys_devices_cpu_info(st);
}

#if INCLUDE_JFR

void os::jfr_report_memory_info() {
  os::Linux::meminfo_t info;
  if (os::Linux::query_process_memory_info(&info)) {
    // Send the RSS JFR event
    EventResidentSetSize event;
    event.set_size(info.vmrss * K);
    event.set_peak(info.vmhwm * K);
    event.commit();
  } else {
    // Log a warning
    static bool first_warning = true;
    if (first_warning) {
      log_warning(jfr)("Error fetching RSS values: query_process_memory_info failed");
      first_warning = false;
    }
  }

src/hotspot/os/windows/os_windows.cpp:

#if INCLUDE_JFR

void os::jfr_report_memory_info() {
  PROCESS_MEMORY_COUNTERS_EX pmex;
  ZeroMemory(&pmex, sizeof(PROCESS_MEMORY_COUNTERS_EX));
  pmex.cb = sizeof(pmex);

  BOOL ret = GetProcessMemoryInfo(GetCurrentProcess(), (PROCESS_MEMORY_COUNTERS*) &pmex, sizeof(pmex));
  if (ret != 0) {
    // Send the RSS JFR event
    EventResidentSetSize event;
    event.set_size(pmex.WorkingSetSize);
    event.set_peak(pmex.PeakWorkingSetSize);
    event.commit();
  } else {
    // Log a warning
    static bool first_warning = true;
    if (first_warning) {
      log_warning(jfr)("Error fetching RSS values: GetProcessMemoryInfo failed");
      first_warning = false;
    }
  }

src/hotspot/os/bsd/os_bsd.cpp:

void os::print_memory_mappings(char* addr, size_t bytes, outputStream* st) {}

#if INCLUDE_JFR

void os::jfr_report_memory_info() {
#ifdef __APPLE__
  mach_task_basic_info info;
  mach_msg_type_number_t count = MACH_TASK_BASIC_INFO_COUNT;

  kern_return_t ret = task_info(mach_task_self(), MACH_TASK_BASIC_INFO, (task_info_t)&info, &count);
  if (ret == KERN_SUCCESS) {
    // Send the RSS JFR event
    EventResidentSetSize event;
    event.set_size(info.resident_size);
    // We've seen that resident_size_max sometimes trails resident_size with one page.
    // Make sure we always report size <= peak
    event.set_peak(MAX2(info.resident_size_max, info.resident_size));
    event.commit();
  } else {
    // Log a warning
    static bool first_warning = true;
    if (first_warning) {
      log_warning(jfr)("Error fetching RSS values: task_info failed");
      first_warning = false;

Event configuration settings across JFR profiles
Configuration enabled period
default true 1000 ms
profiling true 1000 ms

Event fields with their types and descriptions
Field Type Description
size ulong: bytes Resident Set Size Resident set size of the process
peak ulong: bytes Resident Set Size Peak Value Resident set size peak value of the process

Examples 3
Example event data values and properties
peak ulong: bytes
7890067456
size ulong: bytes
6009307136
startTime long: millis
454319274502
Example event data values and properties
peak ulong: bytes
389955584
size ulong: bytes
172646400
startTime long: millis
7451584992
Example event data values and properties
peak ulong: bytes
5194817536
size ulong: bytes
2578329600
startTime long: millis
486869974674

NativeMemoryUsage

default profiling startTime duration every chunk 20 21 25 27 28

Category: Java Virtual Machine / Memory

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Native memory usage for a given memory tag in the JVM

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrNativeMemoryEvent.cpp:

    return;
  }

  NMTUsage* usage = get_usage(timestamp);

  EventNativeMemoryUsageTotal event(UNTIMED);
  event.set_starttime(timestamp);
  event.set_reserved(usage->total_reserved());
  event.set_committed(usage->total_committed());
  event.commit();
}

void JfrNativeMemoryEvent::send_type_event(const Ticks& starttime, MemTag mem_tag, size_t reserved, size_t committed) {
  EventNativeMemoryUsage event(UNTIMED);
  event.set_starttime(starttime);
  event.set_type(NMTUtil::tag_to_index(mem_tag));
  event.set_reserved(reserved);
  event.set_committed(committed);
  event.commit();
}

void JfrNativeMemoryEvent::send_type_events(const Ticks& timestamp) {
  if (!MemTracker::enabled()) {
    return;
  }

Event configuration settings across JFR profiles
Configuration enabled period
default true 1000 ms
profiling true 1000 ms

Event fields with their types and descriptions
Field Type Description
type NMTType Memory Type Type used for the native memory allocation
reserved ulong: bytes Reserved Memory Reserved bytes for this type
committed ulong: bytes Committed Memory Committed bytes for this type

Examples 3
Example event data values and properties
committed ulong: bytes
13733536
reserved ulong: bytes
13733536
startTime long: millis
1229976068
type NMTType
Arena Chunk
Example event data values and properties
committed ulong: bytes
2867167
reserved ulong: bytes
2867167
startTime long: millis
4396431159
type NMTType
Symbol
Example event data values and properties
committed ulong: bytes
0
reserved ulong: bytes
0
startTime long: millis
1332270313
type NMTType
JVMCI

NativeMemoryUsageTotal

default profiling startTime duration every chunk 20 21 25 27 28

Category: Java Virtual Machine / Memory

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Total native memory usage for the JVM. Might not be the exact sum of the NativeMemoryUsage events due to timeing.

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrNativeMemoryEvent.cpp:

    usage->refresh();
    last_timestamp = timestamp;
  }
  return usage;
}

void JfrNativeMemoryEvent::send_total_event(const Ticks& timestamp) {
  if (!MemTracker::enabled()) {
    return;
  }

  NMTUsage* usage = get_usage(timestamp);

  EventNativeMemoryUsageTotal event(UNTIMED);
  event.set_starttime(timestamp);
  event.set_reserved(usage->total_reserved());
  event.set_committed(usage->total_committed());
  event.commit();
}

void JfrNativeMemoryEvent::send_type_event(const Ticks& starttime, MemTag mem_tag, size_t reserved, size_t committed) {
  EventNativeMemoryUsage event(UNTIMED);
  event.set_starttime(starttime);
  event.set_type(NMTUtil::tag_to_index(mem_tag));
  event.set_reserved(reserved);

Event configuration settings across JFR profiles
Configuration enabled period
default true 1000 ms
profiling true 1000 ms

Event fields with their types and descriptions
Field Type Description
reserved ulong: bytes Reserved Memory Total amount of reserved bytes for the JVM
committed ulong: bytes Committed Memory Total amount of committed bytes for the JVM

Examples 3
Example event data values and properties
committed ulong: bytes
352058332
reserved ulong: bytes
5696392156
startTime long: millis
4396431159
Example event data values and properties
committed ulong: bytes
878085849
reserved ulong: bytes
5779695321
startTime long: millis
18458020220
Example event data values and properties
committed ulong: bytes
275951092
reserved ulong: bytes
5803138548
startTime long: millis
22876644493

JVM: Method Tracing

MethodTiming

default profiling startTime duration stackTrace 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/MethodTimingEvent.java

Category: Java Virtual Machine / Method Tracing

Measures the approximate time it takes for a method to execute, including all delays, not just CPU processing time

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void timingObjectInit(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addObjectTiming(duration);
        }
    }

    public static void traceTimingObjectInit(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTraceEvent.shouldCommit(duration) && JVM.getEventWriter() != null) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addObjectTiming(duration);
        }
    }

    public static void trace(long startTime, long methodId) {

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void timing(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addTiming(methodId, duration);
        }
    }

    public static void traceTiming(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addTiming(methodId, duration);
        }
        if (MethodTraceEvent.shouldCommit(duration)) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void timingObjectInit(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addObjectTiming(duration);
        }
    }

    public static void traceTimingObjectInit(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTraceEvent.shouldCommit(duration) && JVM.getEventWriter() != null) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addObjectTiming(duration);
        }
    }

    public static void trace(long startTime, long methodId) {

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void timing(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addTiming(methodId, duration);
        }
    }

    public static void traceTiming(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addTiming(methodId, duration);
        }
        if (MethodTraceEvent.shouldCommit(duration)) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }

src/jdk.jfr/share/classes/jdk/jfr/internal/tracing/PlatformTracer.java:

        s.append(message);
        s.append(" for ");
        s.append(className.replace("/", "."));
        s.append(" in module ");
        s.append(module.getName());
        s.append(" and class loader " + module.getClassLoader());
        Logger.log(LogTag.JFR_METHODTRACE, level, s.toString());
    }

    public static void emitTiming() {
        // Metadata lock prevents rotation/flush while emitting events.
        synchronized (MetadataRepository.getInstance()) {
            removeClasses(JVM.drainStaleMethodTracerIds());
            long timestamp = MethodTimingEvent.timestamp();
            for (var tc : timedClasses.values()) {
                tc.emit(timestamp);
            }
        }
    }

    public static void addObjectTiming(long duration) {
        OBJECT.invocations().getAndIncrement();
        OBJECT.time().addAndGet(duration);
        OBJECT.updateMinMax(duration);
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/tracing/PlatformTracer.java:

        s.append(message);
        s.append(" for ");
        s.append(className.replace("/", "."));
        s.append(" in module ");
        s.append(module.getName());
        s.append(" and class loader " + module.getClassLoader());
        Logger.log(LogTag.JFR_METHODTRACE, level, s.toString());
    }

    public static void emitTiming() {
        // Metadata lock prevents rotation/flush while emitting events.
        synchronized (MetadataRepository.getInstance()) {
            removeClasses(JVM.drainStaleMethodTracerIds());
            long timestamp = MethodTimingEvent.timestamp();
            for (var tc : timedClasses.values()) {
                tc.emit(timestamp);
            }
        }
    }

    public static void addObjectTiming(long duration) {
        OBJECT.invocations().getAndIncrement();
        OBJECT.time().addAndGet(duration);
        OBJECT.updateMinMax(duration);
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/tracing/TimedClass.java:

    public void emit(long timestamp) {
        for (var tm : methods.values()) {
            if (tm.published().get()) {
                long methodId = tm.method().methodId();
                long invocations = tm.invocations().get();
                long time = tm.time().get();
                long min = tm.minimum().get();
                long max = tm.maximum().get();
                if (time == 0 || invocations == 0) {
                    // If time is zero, it's a low resolution clock and more invocations are needed.
                    MethodTimingEvent.commit(timestamp, methodId, invocations, MISSING, MISSING, MISSING);
                } else {
                    long average = (time + invocations / 2) / invocations;
                    if (min == Long.MAX_VALUE) {
                        min = average;
                    }
                    if (max == Long.MIN_VALUE) {
                        max = average;
                    }
                    min = Math.min(min, average);
                    max = Math.max(max, average);
                    MethodTimingEvent.commit(timestamp, methodId, invocations, min, average, max);
                }
                tm.method().log("Emitted event");
            }
        }
    }
}

src/jdk.jfr/share/classes/jdk/jfr/internal/tracing/TimedClass.java:

    public void emit(long timestamp) {
        for (var tm : methods.values()) {
            if (tm.published().get()) {
                long methodId = tm.method().methodId();
                long invocations = tm.invocations().get();
                long time = tm.time().get();
                long min = tm.minimum().get();
                long max = tm.maximum().get();
                if (time == 0 || invocations == 0) {
                    // If time is zero, it's a low resolution clock and more invocations are needed.
                    MethodTimingEvent.commit(timestamp, methodId, invocations, MISSING, MISSING, MISSING);
                } else {
                    long average = (time + invocations / 2) / invocations;
                    if (min == Long.MAX_VALUE) {
                        min = average;
                    }
                    if (max == Long.MIN_VALUE) {
                        max = average;
                    }
                    min = Math.min(min, average);
                    max = Math.max(max, average);
                    MethodTimingEvent.commit(timestamp, methodId, invocations, min, average, max);
                }
                tm.method().log("Emitted event");
            }
        }
    }
}

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        jdk.internal.event.VirtualThreadEndEvent.class,
        jdk.internal.event.VirtualThreadSubmitFailedEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,
        jdk.internal.event.FinalFieldMutationEvent.class,
        DirectBufferStatisticsEvent.class,
        InitialSecurityPropertyEvent.class,
        MethodTraceEvent.class,
        MethodTimingEvent.class,
    };

    private static final Runnable emitExceptionStatistics = JDKEvents::emitExceptionStatistics;
    private static final Runnable emitDirectBufferStatistics = JDKEvents::emitDirectBufferStatistics;
    private static final Runnable emitContainerConfiguration = JDKEvents::emitContainerConfiguration;
    private static final Runnable emitContainerCPUUsage = JDKEvents::emitContainerCPUUsage;
    private static final Runnable emitContainerCPUThrottling = JDKEvents::emitContainerCPUThrottling;

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        try {
            if (initializationTriggered == false) {
                for (Class<?> eventClass : eventClasses) {
                    MetadataRepository.getInstance().register((Class<? extends Event>) eventClass);
                }
                PeriodicEvents.addJavaEvent(jdk.internal.event.ExceptionStatisticsEvent.class, emitExceptionStatistics);
                PeriodicEvents.addJavaEvent(DirectBufferStatisticsEvent.class, emitDirectBufferStatistics);
                PeriodicEvents.addJavaEvent(InitialSecurityPropertyEvent.class, emitInitialSecurityProperties);
                PeriodicEvents.addJavaEvent(MethodTimingEvent.class, emitMethodTiming);

                initializeContainerEvents();
                JFRTracing.enable();
                initializationTriggered = true;
            }
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not initialize JDK events. " + e.getMessage());

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

            for (String key : p.stringPropertyNames()) {
                InitialSecurityPropertyEvent e = new InitialSecurityPropertyEvent();
                e.key = key;
                e.value = p.getProperty(key);
                e.commit();
            }
        }
    }

    private static void emitMethodTiming() {
        if (MethodSetting.isInitialized() && MethodTimingEvent.enabled()) {
            PlatformTracer.emitTiming();
        }
    }
}

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        jdk.internal.event.VirtualThreadEndEvent.class,
        jdk.internal.event.VirtualThreadSubmitFailedEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,
        jdk.internal.event.FinalFieldMutationEvent.class,
        DirectBufferStatisticsEvent.class,
        InitialSecurityPropertyEvent.class,
        MethodTraceEvent.class,
        MethodTimingEvent.class,
    };

    private static final Runnable emitExceptionStatistics = JDKEvents::emitExceptionStatistics;
    private static final Runnable emitDirectBufferStatistics = JDKEvents::emitDirectBufferStatistics;
    private static final Runnable emitContainerConfiguration = JDKEvents::emitContainerConfiguration;
    private static final Runnable emitContainerCPUUsage = JDKEvents::emitContainerCPUUsage;
    private static final Runnable emitContainerCPUThrottling = JDKEvents::emitContainerCPUThrottling;

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        try {
            if (initializationTriggered == false) {
                for (Class<?> eventClass : eventClasses) {
                    MetadataRepository.getInstance().register((Class<? extends Event>) eventClass);
                }
                PeriodicEvents.addJavaEvent(jdk.internal.event.ExceptionStatisticsEvent.class, emitExceptionStatistics);
                PeriodicEvents.addJavaEvent(DirectBufferStatisticsEvent.class, emitDirectBufferStatistics);
                PeriodicEvents.addJavaEvent(InitialSecurityPropertyEvent.class, emitInitialSecurityProperties);
                PeriodicEvents.addJavaEvent(MethodTimingEvent.class, emitMethodTiming);

                initializeContainerEvents();
                JFRTracing.enable();
                initializationTriggered = true;
            }
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not initialize JDK events. " + e.getMessage());

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

            for (String key : p.stringPropertyNames()) {
                InitialSecurityPropertyEvent e = new InitialSecurityPropertyEvent();
                e.key = key;
                e.value = p.getProperty(key);
                e.commit();
            }
        }
    }

    private static void emitMethodTiming() {
        if (MethodSetting.isInitialized() && MethodTimingEvent.enabled()) {
            PlatformTracer.emitTiming();
        }
    }
}

src/jdk.jfr/share/classes/jdk/jfr/events/MethodTimingEvent.java:

@Name("jdk.MethodTiming")
@Label("Method Timing")
@Category({ "Java Virtual Machine", "Method Tracing" })
@RemoveFields({ "duration", "eventThread", "stackTrace" })
@Description("Measures the approximate time it takes for a method to execute, including all delays, not just CPU processing time")
public final class MethodTimingEvent extends AbstractJDKEvent {

    @Label("Method")
    public long method;

    @Label("Invocations")
    public long invocations;

    @Label("Minimum Time")
    @Description("The value may be missing (Long.MIN_VALUE) if the clock-resolution is too low to establish a minimum time")
    @Timespan(Timespan.TICKS)
    public long minimum;

src/jdk.jfr/share/classes/jdk/jfr/events/MethodTimingEvent.java:

@Name("jdk.MethodTiming")
@Label("Method Timing")
@Category({ "Java Virtual Machine", "Method Tracing" })
@RemoveFields({ "duration", "eventThread", "stackTrace" })
@Description("Measures the approximate time it takes for a method to execute, including all delays, not just CPU processing time")
public final class MethodTimingEvent extends AbstractJDKEvent {

    @Label("Method")
    public long method;

    @Label("Invocations")
    public long invocations;

    @Label("Minimum Time")
    @Description("The value may be missing (Long.MIN_VALUE) if the clock-resolution is too low to establish a minimum time")
    @Timespan(Timespan.TICKS)
    public long minimum;

Event configuration settings across JFR profiles
Configuration enabled filter period
default true null endChunk
profiling true null endChunk

Event fields with their types and descriptions
Field Type Description
method long Method
invocations long Invocations
minimum long: tickspan Minimum Time The value may be missing (Long.MIN_VALUE) if the clock-resolution is too low to establish a minimum time
average long: tickspan Average Time The value may be missing (Long.MIN_VALUE) if the clock-resolution is too low to establish an average time
maximum long: tickspan Maximum Time The value may be missing (Long.MIN_VALUE) if the clock-resolution is too low to establish a maximum time

MethodTrace

default profiling startTime duration stackTrace 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/MethodTraceEvent.java

Category: Java Virtual Machine / Method Tracing

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void traceObjectInit(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTraceEvent.shouldCommit(duration) && JVM.getEventWriter() != null) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
    }

    public static void timingObjectInit(long startTime, long methodId) {

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void traceTimingObjectInit(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTraceEvent.shouldCommit(duration) && JVM.getEventWriter() != null) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addObjectTiming(duration);
        }

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void trace(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTraceEvent.shouldCommit(duration)) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
    }

    public static void timing(long startTime, long methodId) {

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addTiming(methodId, duration);
        }
        if (MethodTraceEvent.shouldCommit(duration)) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
    }
}

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void traceObjectInit(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTraceEvent.shouldCommit(duration) && JVM.getEventWriter() != null) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
    }

    public static void timingObjectInit(long startTime, long methodId) {

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void traceTimingObjectInit(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTraceEvent.shouldCommit(duration) && JVM.getEventWriter() != null) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addObjectTiming(duration);
        }

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void trace(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTraceEvent.shouldCommit(duration)) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
    }

    public static void timing(long startTime, long methodId) {

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addTiming(methodId, duration);
        }
        if (MethodTraceEvent.shouldCommit(duration)) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
    }
}

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        jdk.internal.event.SerializationMisdeclarationEvent.class,
        jdk.internal.event.SocketReadEvent.class,
        jdk.internal.event.SocketWriteEvent.class,
        jdk.internal.event.ThreadSleepEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.VirtualThreadStartEvent.class,
        jdk.internal.event.VirtualThreadEndEvent.class,
        jdk.internal.event.VirtualThreadSubmitFailedEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,
        jdk.internal.event.FinalFieldMutationEvent.class,
        DirectBufferStatisticsEvent.class,
        InitialSecurityPropertyEvent.class,
        MethodTraceEvent.class,
        MethodTimingEvent.class,
    };

    private static final Runnable emitExceptionStatistics = JDKEvents::emitExceptionStatistics;
    private static final Runnable emitDirectBufferStatistics = JDKEvents::emitDirectBufferStatistics;
    private static final Runnable emitContainerConfiguration = JDKEvents::emitContainerConfiguration;
    private static final Runnable emitContainerCPUUsage = JDKEvents::emitContainerCPUUsage;
    private static final Runnable emitContainerCPUThrottling = JDKEvents::emitContainerCPUThrottling;
    private static final Runnable emitContainerMemoryUsage = JDKEvents::emitContainerMemoryUsage;
    private static final Runnable emitContainerIOUsage = JDKEvents::emitContainerIOUsage;
    private static final Runnable emitInitialSecurityProperties = JDKEvents::emitInitialSecurityProperties;

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        jdk.internal.event.SerializationMisdeclarationEvent.class,
        jdk.internal.event.SocketReadEvent.class,
        jdk.internal.event.SocketWriteEvent.class,
        jdk.internal.event.ThreadSleepEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.VirtualThreadStartEvent.class,
        jdk.internal.event.VirtualThreadEndEvent.class,
        jdk.internal.event.VirtualThreadSubmitFailedEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,
        jdk.internal.event.FinalFieldMutationEvent.class,
        DirectBufferStatisticsEvent.class,
        InitialSecurityPropertyEvent.class,
        MethodTraceEvent.class,
        MethodTimingEvent.class,
    };

    private static final Runnable emitExceptionStatistics = JDKEvents::emitExceptionStatistics;
    private static final Runnable emitDirectBufferStatistics = JDKEvents::emitDirectBufferStatistics;
    private static final Runnable emitContainerConfiguration = JDKEvents::emitContainerConfiguration;
    private static final Runnable emitContainerCPUUsage = JDKEvents::emitContainerCPUUsage;
    private static final Runnable emitContainerCPUThrottling = JDKEvents::emitContainerCPUThrottling;
    private static final Runnable emitContainerMemoryUsage = JDKEvents::emitContainerMemoryUsage;
    private static final Runnable emitContainerIOUsage = JDKEvents::emitContainerIOUsage;
    private static final Runnable emitInitialSecurityProperties = JDKEvents::emitInitialSecurityProperties;

src/jdk.jfr/share/classes/jdk/jfr/events/MethodTraceEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Contextual;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.StackTrace;

@Name("jdk.MethodTrace")
@Label("Method Trace")
@Category({ "Java Virtual Machine", "Method Tracing" })
@StackTrace(true)
public final class MethodTraceEvent extends AbstractJDKEvent {

    @Contextual
    @Label("Method")
    private long method;

    public static void commit(long start, long duration, long method) {
        // Generated by JFR
    }

    public static long timestamp() {
        // Generated by JFR
        return 0;

src/jdk.jfr/share/classes/jdk/jfr/events/MethodTraceEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Contextual;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.StackTrace;

@Name("jdk.MethodTrace")
@Label("Method Trace")
@Category({ "Java Virtual Machine", "Method Tracing" })
@StackTrace(true)
public final class MethodTraceEvent extends AbstractJDKEvent {

    @Contextual
    @Label("Method")
    private long method;

    public static void commit(long start, long duration, long method) {
        // Generated by JFR
    }

    public static long timestamp() {
        // Generated by JFR
        return 0;

Event configuration settings across JFR profiles
Configuration enabled filter stackTrace threshold
default true null true 0 ms
profiling true null true 0 ms

JVM: Profiling

OldObjectSample

cutoff default profiling startTime eventThread stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / Profiling

Appearing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: linux_ShenandoahGC, linux_ZGC

A potential memory leak

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/leakprofiler/checkpoint/eventEmitter.cpp:

  assert(!sample->is_dead(), "invariant");
  assert(edge_store != nullptr, "invariant");
  assert(_jfr_thread_local != nullptr, "invariant");

  const StoredEdge* const edge = edge_store->get(sample);
  assert(edge != nullptr, "invariant");
  assert(edge->pointee() == sample->object(), "invariant");
  const traceid object_id = edge_store->get_id(edge);
  assert(object_id != 0, "invariant");
  const traceid gc_root_id = edge->gc_root_id();

  Tickspan object_age = Ticks(_start_time.value()) - sample->allocation_time();

  EventOldObjectSample e(UNTIMED);
  e.set_starttime(_start_time);
  e.set_endtime(_end_time);
  e.set_allocationTime(sample->allocation_time());
  e.set_objectSize(sample->allocated());
  e.set_objectAge(object_age);
  e.set_lastKnownHeapUsage(sample->heap_used_at_last_gc());
  e.set_object(object_id);
  e.set_arrayElements(array_size(edge->pointee()));
  e.set_root(gc_root_id);

  // Temporarily assigning both the stack trace id and thread id

src/hotspot/share/jfr/leakprofiler/sampling/objectSampler.cpp:

    // for regular threads, the blob is cached in the thread local data structure
    tl->set_thread_blob(JfrCheckpointManager::create_thread_blob(thread, tid));
    assert(tl->has_thread_blob(), "invariant");
  }
  return tl->thread_blob();
}

class RecordStackTrace {
 private:
  JavaThread* _jt;
  bool _enabled;
 public:
  RecordStackTrace(JavaThread* jt) : _jt(jt),
    _enabled(JfrEventSetting::has_stacktrace(EventOldObjectSample::eventId)) {
    if (_enabled) {
      JfrStackTraceRepository::record_for_leak_profiler(jt);
    }
  }
  ~RecordStackTrace() {
    if (_enabled) {
      _jt->jfr_thread_local()->clear_cached_stack_trace();
    }
  }
};

src/hotspot/share/jfr/recorder/service/jfrRecorderService.cpp:

                                                  bool skip_bfs) {
  JavaThread* const jt = JavaThread::current();
  DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_native(jt);)
  if (exclude_paths_to_gc_roots(cutoff_ticks)) {
    ::emit_leakprofiler_events(emit_all, skip_bfs, jt);
    return;
  }
  emit_leakprofiler_events_paths_to_gc_roots(cutoff_ticks, emit_all, skip_bfs, /* oom */ false, jt);
}

// Leakprofiler serialization request, the report_on_java_out_of_memory VM entry point.
void JfrRecorderService::emit_leakprofiler_events_on_oom() {
  assert(CrashOnOutOfMemoryError, "invariant");
  if (EventOldObjectSample::is_enabled()) {
    JavaThread* const jt = JavaThread::current();
    DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(jt);)
    ThreadToNativeFromVM transition(jt);
    emit_leakprofiler_events_paths_to_gc_roots(max_jlong, false, false, /* oom */ true, jt);
  }
}

// The worker routine for the JFR Recorder Thread when processing MSG_EMIT_LEAKP_REFCHAINS messages.
void JfrRecorderService::emit_leakprofiler_events() {
  JavaThread* const jt = JavaThread::current();
  DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_native(jt));

src/hotspot/share/jfr/jni/jfrJniMethod.cpp:

NO_TRANSITION(jlong, jfr_elapsed_counter(JNIEnv* env, jclass jvm))
  return JfrTicks::now();
NO_TRANSITION_END

NO_TRANSITION(void, jfr_retransform_classes(JNIEnv* env, jclass jvm, jobjectArray classes))
  JfrJvmtiAgent::retransform_classes(env, classes, JavaThread::thread_from_jni_environment(env));
NO_TRANSITION_END

NO_TRANSITION(void, jfr_set_enabled(JNIEnv* env, jclass jvm, jlong event_type_id, jboolean enabled))
  JfrEventSetting::set_enabled(event_type_id, JNI_TRUE == enabled);
  if (EventOldObjectSample::eventId == event_type_id) {
    JavaThread* thread = JavaThread::thread_from_jni_environment(env);
    MACOS_AARCH64_ONLY(ThreadWXEnable __wx(WXWrite, thread));
    ThreadInVMfromNative transition(thread);
    if (JNI_TRUE == enabled) {
      LeakProfiler::start(JfrOptionSet::old_object_queue_size());
    } else {
      LeakProfiler::stop();
    }
  }
NO_TRANSITION_END

Event configuration settings across JFR profiles
Configuration cutoff enabled stackTrace
default 0 ns true false
profiling 0 ns true true

Event fields with their types and descriptions
Field Type Description
allocationTime Ticks Allocation Time
objectSize ulong: bytes 18+ Object Size
objectAge Tickspan 14+ Object Age
lastKnownHeapUsage ulong: bytes Last Known Heap Usage
object OldObject Object
arrayElements int Array Elements If the object is an array, the number of elements, or minimum value for the type int if it is not an array
root OldObjectGcRoot GC Root

Examples 3
Example event data values and properties
allocationTime Ticks
1329760296
arrayElements int
-2147483648
lastKnownHeapUsage ulong: bytes
6531952
object OldObject
address ulong: address
30174075600
description string
Class Name: java.lang.ref.Finalizer$1
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Class
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
objectAge Tickspan
24110980902
objectSize ulong: bytes
112
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
13
lineNumber int
137
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
runFinalization
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
16
name string
java/lang/ref/Finalizer
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang/ref
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
25440741198
Example event data values and properties
allocationTime Ticks
160917278024
arrayElements int
-2147483648
lastKnownHeapUsage ulong: bytes
118468304
object OldObject
address ulong: address
30224175704
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/ConcurrentHashMap
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent
objectAge Tickspan
339260600631
objectSize ulong: bytes
64
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
4
lineNumber int
342
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
<clinit>
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
10
name string
org/apache/spark/util/kvstore/InMemoryStore$InMemoryView
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/util/kvstore
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
500177878655
Example event data values and properties
allocationTime Ticks
86467254786
arrayElements int
70
lastKnownHeapUsage ulong: bytes
85882256
object OldObject
address ulong: address
30207367288
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
objectAge Tickspan
423924215979
objectSize ulong: bytes
88
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
-1
lineNumber int
314
method Method
descriptor string
(Ljava/lang/Object;)Lscala/collection/mutable/Growable;
hidden boolean
false
modifiers int
17
name string
$plus$eq
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1025
name string
scala/collection/mutable/AbstractBuffer
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection/mutable
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
510391470765

ExecutionSample

default profiling startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Profiling

Snapshot of a thread executing Java code. Threads that are not executing Java code, including those waiting or executing native code, are not included.

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/jni/jfrJniMethod.cpp:

JVM_ENTRY_NO_ENV(void, jfr_subscribe_log_level(JNIEnv* env, jclass jvm, jobject log_tag, jint id))
  JfrJavaLog::subscribe_log_level(log_tag, id, thread);
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_set_output(JNIEnv* env, jclass jvm, jstring path))
  JfrRepository::set_chunk_path(path, thread);
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_set_method_sampling_period(JNIEnv* env, jclass jvm, jlong type, jlong periodMillis))
  if (periodMillis < 0) {
    periodMillis = 0;
  }
  JfrEventId typed_event_id = (JfrEventId)type;
  assert(EventExecutionSample::eventId == typed_event_id || EventNativeMethodSample::eventId == typed_event_id, "invariant");
  JfrEventSetting::set_enabled(typed_event_id, periodMillis > 0);
  if (EventExecutionSample::eventId == type) {
    JfrThreadSampler::set_java_sample_period(periodMillis);
  } else {
    JfrThreadSampler::set_native_sample_period(periodMillis);
  }
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_store_metadata_descriptor(JNIEnv* env, jclass jvm, jbyteArray descriptor))
  JfrMetadataEvent::update(descriptor);
JVM_END

// trace thread id for a thread object

src/hotspot/share/jfr/periodic/sampling/jfrThreadSampling.cpp:

  traceid sid;
  {
    ResourceMark rm(current);
    JfrStackTrace stacktrace;
    if (!stacktrace.record(jt, top_frame, in_continuation, request)) {
      // Unable to record stacktrace. Fail.
      return;
    }
    sid = JfrStackTraceRepository::add(stacktrace);
  }
  assert(sid != 0, "invariant");
  const traceid tid = in_continuation ? tl->vthread_id_with_epoch_update(jt) : JfrThreadLocal::jvm_thread_id(jt);
  send_sample_event<EventExecutionSample>(request._sample_ticks, now, sid, tid);
  if (current == jt) {
    send_safepoint_latency_event(request, now, sid, jt);
  }
}

#ifdef LINUX
static void record_cpu_time_thread(const JfrCPUTimeSampleRequest& request, const JfrTicks& now, const JfrThreadLocal* tl, JavaThread* jt, Thread* current) {
  assert(jt != nullptr, "invariant");
  assert(tl != nullptr, "invariant");
  assert(current != nullptr, "invariant");
  frame top_frame;

Event configuration settings across JFR profiles
Configuration enabled period
default true 20 ms
profiling true 10 ms

Event fields with their types and descriptions
Field Type Description
sampledThread Thread Thread
stackTrace StackTrace Stack Trace
state ThreadState Thread State

Examples 3
Example event data values and properties
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
5014
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
117
lineNumber int
2465
method Method
descriptor string
([Ljava/util/concurrent/ConcurrentHashMap$Node;[Ljava/util/concurrent/ConcurrentHashMap$Node;)V
hidden boolean
false
modifiers int
18
name string
transfer
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/ConcurrentHashMap
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
395864291
state ThreadState
STATE_RUNNABLE
Example event data values and properties
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 2.0 in stage 47.0 (TID 184)
javaThreadId long
1733
osName string
Executor task launch worker for task 2.0 in stage 47.0 (TID 184)
osThreadId long
4650
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
17
lineNumber int
124
method Method
descriptor string
(Ljava/lang/Object;)I
hidden boolean
false
modifiers int
9
name string
anyHash
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
scala/runtime/Statics
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/runtime
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
454247606719
state ThreadState
STATE_RUNNABLE
Example event data values and properties
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 0.0 in stage 38.0 (TID 146)
javaThreadId long
1711
osName string
Executor task launch worker for task 0.0 in stage 38.0 (TID 146)
osThreadId long
4234
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
9
lineNumber int
119
method Method
descriptor string
(Ljava/lang/Object;Ljava/lang/Object;)Z
hidden boolean
false
modifiers int
9
name string
equals
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
scala/runtime/BoxesRunTime
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/runtime
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
448553546637
state ThreadState
STATE_RUNNABLE

NativeMethodSample

default profiling startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Profiling

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Snapshot of a thread in native code, executing or waiting. Threads that are executing Java code are not included.

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/jni/jfrJniMethod.cpp:

JVM_ENTRY_NO_ENV(void, jfr_subscribe_log_level(JNIEnv* env, jclass jvm, jobject log_tag, jint id))
  JfrJavaLog::subscribe_log_level(log_tag, id, thread);
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_set_output(JNIEnv* env, jclass jvm, jstring path))
  JfrRepository::set_chunk_path(path, thread);
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_set_method_sampling_period(JNIEnv* env, jclass jvm, jlong type, jlong periodMillis))
  if (periodMillis < 0) {
    periodMillis = 0;
  }
  JfrEventId typed_event_id = (JfrEventId)type;
  assert(EventExecutionSample::eventId == typed_event_id || EventNativeMethodSample::eventId == typed_event_id, "invariant");
  JfrEventSetting::set_enabled(typed_event_id, periodMillis > 0);
  if (EventExecutionSample::eventId == type) {
    JfrThreadSampler::set_java_sample_period(periodMillis);
  } else {
    JfrThreadSampler::set_native_sample_period(periodMillis);
  }
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_store_metadata_descriptor(JNIEnv* env, jclass jvm, jbyteArray descriptor))
  JfrMetadataEvent::update(descriptor);
JVM_END

src/hotspot/share/jfr/periodic/sampling/jfrThreadSampling.cpp:

      const frame top_frame = jt->last_frame();
      if (!stacktrace.record_inner(jt, top_frame, is_in_continuation(top_frame, jt), 0 /* skip level */)) {
        // Unable to record stacktrace. Fail.
        return false;
      }
      sid = JfrStackTraceRepository::add(stacktrace);
    }
    // Read the tid under the monitor to ensure that if its a virtual thread,
    // it is not unmounted until we are done with it.
    tid = JfrThreadLocal::thread_id(jt);
  }

  assert(tl->sample_state() == NO_SAMPLE, "invariant");
  send_sample_event<EventNativeMethodSample>(start_time, start_time, sid, tid);
  return true;
}

// Entry point for a sampled thread that discovered pending Jfr Sample Requests as part of a safepoint poll.
void JfrThreadSampling::process_sample_request(JavaThread* jt) {
  assert(JavaThread::current() == jt, "should be current thread");
  assert(jt->thread_state() == _thread_in_vm || jt->thread_state() == _thread_in_Java, "invariant");

  const JfrTicks now = JfrTicks::now();

  JfrThreadLocal* const tl = jt->jfr_thread_local();

Event configuration settings across JFR profiles
Configuration enabled period
default true 20 ms
profiling true 20 ms

Event fields with their types and descriptions
Field Type Description
sampledThread Thread Thread
stackTrace StackTrace Stack Trace
state ThreadState Thread State

Examples 3
Example event data values and properties
sampledThread Thread
group ThreadGroup
name string
finagle/netty4
parent ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
finagle/netty4-2-1
javaThreadId long
883
osName string
finagle/netty4-2-1
osThreadId long
3325
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(IJII)I
hidden boolean
false
modifiers int
266
name string
epollWait
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
io/netty/channel/epoll/Native
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/channel/epoll
type FrameType
Native
…
truncated boolean
false
startTime long: millis
447643132829
state ThreadState
STATE_RUNNABLE
Example event data values and properties
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
5014
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/io/FileDescriptor;Z)I
hidden boolean
false
modifiers int
264
name string
force0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
sun/nio/ch/UnixFileDispatcherImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
sun/nio/ch
type FrameType
Native
…
truncated boolean
false
startTime long: millis
14274239103
state ThreadState
STATE_RUNNABLE
Example event data values and properties
sampledThread Thread
group ThreadGroup
name string
finagle/netty4/boss
parent ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
finagle/netty4/boss-1
javaThreadId long
887
osName string
finagle/netty4/boss-1
osThreadId long
3701
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(IJII)I
hidden boolean
false
modifiers int
266
name string
epollWait
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
io/netty/channel/epoll/Native
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/channel/epoll
type FrameType
Native
…
truncated boolean
false
startTime long: millis
454580192553
state ThreadState
STATE_RUNNABLE

CPUTimeSample

experimental throttle startTime 25 27 28

Category: Java Virtual Machine / Profiling

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Snapshot of a threads state from the CPU time sampler, both threads executing native and Java code are included. The throttle setting can be either an upper bound for the event emission rate, e.g. 100/s, or the cpu-time period, e.g. 10ms, with s, ms, us and ns supported as time units.

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/sampling/jfrCPUTimeThreadSampler.cpp:

      if (jt->has_last_Java_frame()) {
        JfrThreadSampling::process_cpu_time_request(jt, tl, current, false);
      } else {
        tl->set_do_async_processing_of_cpu_time_jfr_requests(false);
      }
      tl->release_cpu_time_jfr_queue_lock();
    }
  }
}

static volatile size_t count = 0;

void JfrCPUTimeThreadSampling::send_empty_event(const JfrTicks &start_time, traceid tid, Tickspan cpu_time_period) {
  EventCPUTimeSample event(UNTIMED);
  event.set_failed(true);
  event.set_starttime(start_time);
  event.set_eventThread(tid);
  event.set_stackTrace(0);
  event.set_samplingPeriod(cpu_time_period);
  event.set_biased(false);
  event.commit();
}


static volatile size_t biased_count = 0;

void JfrCPUTimeThreadSampling::send_event(const JfrTicks &start_time, traceid sid, traceid tid, Tickspan cpu_time_period, bool biased) {
  EventCPUTimeSample event(UNTIMED);
  event.set_failed(false);
  event.set_starttime(start_time);
  event.set_eventThread(tid);
  event.set_stackTrace(sid);
  event.set_samplingPeriod(cpu_time_period);
  event.set_biased(biased);
  event.commit();
  AtomicAccess::inc(&count);
  if (biased) {
    AtomicAccess::inc(&biased_count);
  }

Event configuration settings across JFR profiles
Configuration enabled stackTrace throttle
default false true 500/s
profiling false true 10ms

Event fields with their types and descriptions
Field Type Description
stackTrace StackTrace Stack Trace
eventThread Thread Thread
failed boolean Failed Failed to obtain the stack trace
samplingPeriod Tickspan CPU Time Sampling Period
biased boolean Biased The sample is safepoint-biased

Examples 3
Example event data values and properties
biased boolean
true
eventThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 2.0 in stage 47.0 (TID 184)
javaThreadId long
1733
osName string
Executor task launch worker for task 2.0 in stage 47.0 (TID 184)
osThreadId long
4650
virtual boolean
false
failed boolean
false
samplingPeriod Tickspan
10000000
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
179
lineNumber int
35
method Method
descriptor string
(Lbreeze/linalg/DenseVector;DLbreeze/linalg/DenseVector;)V
hidden boolean
false
modifiers int
1
name string
apply
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
breeze/linalg/operators/DenseVector_DoubleOps$impl_scaleAdd_InPlace_DV_T_DV_Double$
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg/operators
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
453630400010
Example event data values and properties
biased boolean
false
eventThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 2.0 in stage 38.0 (TID 148)
javaThreadId long
1712
osName string
Executor task launch worker for task 2.0 in stage 38.0 (TID 148)
osThreadId long
4235
virtual boolean
false
failed boolean
false
samplingPeriod Tickspan
10000000
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
234
lineNumber int
3593
method Method
descriptor string
(Lbreeze/linalg/DenseMatrix;Lbreeze/linalg/DenseMatrix;)V
hidden boolean
false
modifiers int
1
name string
apply
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
breeze/linalg/operators/DenseMatrix_SetOps$SetDMDMOp
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg/operators
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
448533435060
Example event data values and properties
biased boolean
true
eventThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
5014
virtual boolean
false
failed boolean
false
samplingPeriod Tickspan
10000000
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
25
lineNumber int
180
method Method
descriptor string
()Ljava/lang/Object;
hidden boolean
false
modifiers int
0
name string
getCarrierThreadLocal
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/ThreadLocal
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
12350404080

CPUTimeSamplesLost

experimental default profiling startTime 25 27 28

Category: Java Virtual Machine / Profiling

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Records that the CPU time sampler lost samples

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/sampling/jfrCPUTimeThreadSampler.cpp:

  event.set_samplingPeriod(cpu_time_period);
  event.set_biased(biased);
  event.commit();
  AtomicAccess::inc(&count);
  if (biased) {
    AtomicAccess::inc(&biased_count);
  }
  if (AtomicAccess::load(&count) % 1000 == 0) {
    log_debug(jfr)("CPU thread sampler sent %zu events, lost %d, biased %zu\n", AtomicAccess::load(&count), AtomicAccess::load(&_lost_samples_sum), AtomicAccess::load(&biased_count));
  }
}

void JfrCPUTimeThreadSampling::send_lost_event(const JfrTicks &time, traceid tid, s4 lost_samples) {
  if (!EventCPUTimeSamplesLost::is_enabled()) {
    return;
  }
  EventCPUTimeSamplesLost event(UNTIMED);
  event.set_starttime(time);
  event.set_lostSamples(lost_samples);
  event.set_eventThread(tid);
  event.commit();
}

void JfrCPUSamplerThread::post_run() {
  this->NonJavaThread::post_run();
  delete this;
}

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
lostSamples int Lost Samples
eventThread Thread Thread

Examples 3
Example event data values and properties
eventThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
5014
virtual boolean
false
lostSamples int
1
startTime long: millis
21363464439
Example event data values and properties
eventThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 3.0 in stage 47.0 (TID 185)
javaThreadId long
1729
osName string
Executor task launch worker for task 3.0 in stage 47.0 (TID 185)
osThreadId long
4645
virtual boolean
false
lostSamples int
3
startTime long: millis
455443451114
Example event data values and properties
eventThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 1.0 in stage 38.0 (TID 147)
javaThreadId long
1713
osName string
Executor task launch worker for task 1.0 in stage 38.0 (TID 147)
osThreadId long
4236
virtual boolean
false
lostSamples int
2
startTime long: millis
448095439615

JVM: Runtime

ContinuationFreeze

experimental startTime duration eventThread stackTrace 19 21 25 27 28

Category: Java Virtual Machine / Runtime

Invocation of Continuation.yield()

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/continuationFreezeThaw.cpp:

  DEBUG_ONLY(log_preempt_after_freeze(cont);)
  return freeze_epilog(cont);
}

template<typename ConfigT, bool preempt>
static inline freeze_result freeze_internal(JavaThread* current, intptr_t* const sp) {
  assert(!current->has_pending_exception(), "");

#ifdef ASSERT
  log_trace(continuations)("~~~~ freeze sp: " INTPTR_FORMAT "JavaThread: " INTPTR_FORMAT, p2i(current->last_continuation()->entry_sp()), p2i(current));
  log_frames(current);
#endif

  CONT_JFR_ONLY(EventContinuationFreeze event;)

  ContinuationEntry* entry = current->last_continuation();

  oop oopCont = entry->cont_oop(current);
  assert(oopCont == current->last_continuation()->cont_oop(current), "");
  assert(ContinuationEntry::assert_entry_frame_laid_out(current), "");

  verify_continuation(oopCont);
  ContinuationWrapper cont(current, oopCont);
  log_develop_debug(continuations)("FREEZE #" INTPTR_FORMAT " " INTPTR_FORMAT, cont.hash(), p2i((oopDesc*)oopCont));

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default false false 0 ms
profiling false false 0 ms

Event fields with their types and descriptions
Field Type Description
carrierThread Thread Carrier Thread Thread enlisted as a carrier
continuationClass Class Continuation Class
interpretedFrames ushort Interpreted Frames
size ushort: bytes Stack Size

ContinuationThaw

experimental startTime duration eventThread stackTrace 19 21 25 27 28

Category: Java Virtual Machine / Runtime

Invocation of Continuation.run() on a started continuation

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/continuationFreezeThaw.cpp:

    " to: " INTPTR_FORMAT " top_address: " INTPTR_FORMAT, p2i(f.sp() - frame::metadata_words), p2i(_top_stack_address));
  ContinuationHelper::Frame::patch_pc(f, f.raw_pc()); // in case we want to deopt the frame in a full transition, this is checked.
  ContinuationHelper::push_pd(f);

  assert(ContinuationHelper::Frame::assert_frame_laid_out(f), "");
}

// returns new top sp
// called after preparations (stack overflow check and making room)
template<typename ConfigT>
static inline intptr_t* thaw_internal(JavaThread* thread, const Continuation::thaw_kind kind) {
  assert(thread == JavaThread::current(), "Must be current thread");

  CONT_JFR_ONLY(EventContinuationThaw event;)

  log_develop_trace(continuations)("~~~~ thaw kind: %d sp: " INTPTR_FORMAT, kind, p2i(thread->last_continuation()->entry_sp()));

  ContinuationEntry* entry = thread->last_continuation();
  assert(entry != nullptr, "");
  oop oopCont = entry->cont_oop(thread);

  assert(!jdk_internal_vm_Continuation::done(oopCont), "");
  assert(oopCont == get_continuation(thread), "");
  verify_continuation(oopCont);

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default false false 0 ms
profiling false false 0 ms

Event fields with their types and descriptions
Field Type Description
carrierThread Thread Carrier Thread Thread enlisted as a carrier
continuationClass Class Continuation Class
interpretedFrames ushort Interpreted Frames
size ushort: bytes Stack Size

ContinuationFreezeFast

experimental startTime eventThread 20 21 25 27 28

Category: Java Virtual Machine / Runtime

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/continuationFreezeThaw.cpp:

  log_develop_trace(continuations)("FREEZE CHUNK #" INTPTR_FORMAT " (young)", _cont.hash());
  LogTarget(Trace, continuations) lt;
  if (lt.develop_is_enabled()) {
    LogStream ls(lt);
    chunk->print_on(true, &ls);
  }

  // Verification
  assert(_cont.chunk_invariant(), "");
  chunk->verify();

#if CONT_JFR
  EventContinuationFreezeFast e;
  if (e.should_commit()) {
    e.set_id(cast_from_oop<u8>(chunk));
    DEBUG_ONLY(e.set_allocate(chunk_is_allocated);)
    e.set_size(cont_size() << LogBytesPerWord);
    e.commit();
  }
#endif
}

NOINLINE freeze_result FreezeBase::freeze_slow() {
#ifdef ASSERT

Event configuration settings across JFR profiles
Configuration enabled
default false
profiling false

Event fields with their types and descriptions
Field Type Description
id ulong Continuation ID
size uint Size
allocate boolean Allocated New

ContinuationFreezeSlow

experimental startTime eventThread 20 21 25 27 28

Category: Java Virtual Machine / Runtime

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/continuationFreezeThaw.cpp:

NOINLINE freeze_result FreezeBase::freeze_slow() {
#ifdef ASSERT
  ResourceMark rm;
#endif

  log_develop_trace(continuations)("freeze_slow  #" INTPTR_FORMAT, _cont.hash());
  assert(_thread->thread_state() == _thread_in_vm || _thread->thread_state() == _thread_blocked, "");

#if CONT_JFR
  EventContinuationFreezeSlow e;
  if (e.should_commit()) {
    e.set_id(cast_from_oop<u8>(_cont.continuation()));
    e.commit();
  }
#endif

  init_rest();

  HandleMark hm(Thread::current());

  frame f = freeze_start_frame();

Event configuration settings across JFR profiles
Configuration enabled
default false
profiling false

Event fields with their types and descriptions
Field Type Description
id ulong Continuation ID

ContinuationThawFast

experimental startTime eventThread 20 21 25 27 28

Category: Java Virtual Machine / Runtime

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/continuationFreezeThaw.cpp:

  log_develop_trace(continuations)("setting entry argsize: %d", _cont.argsize());
  assert(rs.bottom_sp() == _cont.entry()->bottom_sender_sp(), "");

  // install the return barrier if not last frame, or the entry's pc if last
  patch_return(rs.bottom_sp(), is_last);

  // insert the back links from callee to caller frames
  patch_caller_links(rs.top(), rs.top() + rs.total_size());

  assert(is_last == _cont.is_empty(), "");
  assert(_cont.chunk_invariant(), "");

#if CONT_JFR
  EventContinuationThawFast e;
  if (e.should_commit()) {
    e.set_id(cast_from_oop<u8>(chunk));
    e.set_size(thaw_size << LogBytesPerWord);
    e.set_full(!partial);
    e.commit();
  }
#endif

#ifdef ASSERT
  if (LoomDeoptAfterThaw) {
    frame top(rs.sp());

Event configuration settings across JFR profiles
Configuration enabled
default false
profiling false

Event fields with their types and descriptions
Field Type Description
id ulong Continuation ID
full boolean Full
size uint Size

ContinuationThawSlow

experimental startTime eventThread 20 21 25 27 28

Category: Java Virtual Machine / Runtime

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/continuationFreezeThaw.cpp:

  LogTarget(Trace, continuations) lt;
  if (lt.develop_is_enabled()) {
    LogStream ls(lt);
    ls.print_cr("thaw slow return_barrier: %d " INTPTR_FORMAT, kind, p2i(chunk));
    chunk->print_on(true, &ls);
  }

#if CONT_JFR
  EventContinuationThawSlow e;
  if (e.should_commit()) {
    e.set_id(cast_from_oop<u8>(_cont.continuation()));
    e.commit();
  }
#endif

  DEBUG_ONLY(_frames = 0;)
  _align_size = 0;
  int num_frames = kind == Continuation::thaw_top ? 2 : 1;

  _stream = StackChunkFrameStream<ChunkFrames::Mixed>(chunk);

Event configuration settings across JFR profiles
Configuration enabled
default false
profiling false

Event fields with their types and descriptions
Field Type Description
id ulong Continuation ID

ReservedStackActivation

default profiling startTime eventThread stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime

Activation of Reserved Stack Area caused by stack overflow with ReservedStackAccess annotated method in call stack

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/sharedRuntime.cpp:

        for (ScopeDesc *sd = nm->scope_desc_near(fr.pc()); sd != nullptr; sd = sd->sender()) {
          method = sd->method();
          if (method != nullptr && method->has_reserved_stack_access()) {
            found = true;
          }
        }
      }
    }
    if (found) {
      activation = fr;
      warning("Potentially dangerous stack overflow in "
              "ReservedStackAccess annotated method %s [%d]",
              method->name_and_sig_as_C_string(), count++);
      EventReservedStackActivation event;
      if (event.should_commit()) {
        event.set_method(method);
        event.commit();
      }
    }
  }
  return activation;
}

void SharedRuntime::on_slowpath_allocation_exit(JavaThread* current) {
  // After any safepoint, just before going back to compiled code,

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default true true
profiling true true

Event fields with their types and descriptions
Field Type Description
method Method Java Method

SafepointBegin

default profiling startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime / Safepoint

Safepointing begin

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/safepoint.cpp:

static void post_safepoint_begin_event(EventSafepointBegin& event,
                                       uint64_t safepoint_id,
                                       int thread_count,
                                       int critical_thread_count) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.set_totalThreadCount(thread_count);
    event.set_jniCriticalThreadCount(critical_thread_count);
    event.commit();
  }
}

src/hotspot/share/runtime/safepoint.cpp:

    SafepointMechanism::arm_local_poll(cur);
  }
  if (UseSystemMemoryBarrier) {
    SystemMemoryBarrier::emit(); // storestore|storeload, global state -> local state
  } else {
    OrderAccess::fence(); // storestore|storeload, global state -> local state
  }
}

// Roll all threads forward to a safepoint and suspend them all
void SafepointSynchronize::begin() {
  assert(Thread::current()->is_VM_thread(), "Only VM thread may execute a safepoint");

  EventSafepointBegin begin_event;
  SafepointTracing::begin(VMThread::vm_op_type());

  log_trace(safepoint)("Suspending GC threads");
  Universe::heap()->safepoint_synchronize_begin();

  // By getting the Threads_lock, we assure that no threads are about to start or
  // exit. It is released again in SafepointSynchronize::end().
  log_trace(safepoint)("Blocking threads from starting/exiting");
  Threads_lock->lock();

  assert( _state == _not_synchronized, "trying to safepoint synchronize with wrong state");

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 10 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
safepointId ulong Safepoint Identifier
totalThreadCount int Total Threads The total number of threads at the start of safe point
jniCriticalThreadCount int JNI Critical Threads The number of threads in JNI critical sections

Examples 3
Example event data values and properties
jniCriticalThreadCount int
0
safepointId ulong
46
startTime long: millis
1575764084
totalThreadCount int
26
Example event data values and properties
jniCriticalThreadCount int
0
safepointId ulong
548
startTime long: millis
481401371123
totalThreadCount int
51
Example event data values and properties
jniCriticalThreadCount int
0
safepointId ulong
1562
startTime long: millis
454661896219
totalThreadCount int
300

SafepointStateSynchronization

startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime / Safepoint

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Synchronize run state of threads

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/safepoint.cpp:

static void post_safepoint_begin_event(EventSafepointBegin& event,
                                       uint64_t safepoint_id,
                                       int thread_count,
                                       int critical_thread_count) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.set_totalThreadCount(thread_count);
    event.set_jniCriticalThreadCount(critical_thread_count);
    event.commit();
  }
}


static void post_safepoint_synchronize_event(EventSafepointStateSynchronization& event,
                                             uint64_t safepoint_id,
                                             int initial_number_of_threads,
                                             int threads_waiting_to_block,
                                             int iterations) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.set_initialThreadCount(initial_number_of_threads);
    event.set_runningThreadCount(threads_waiting_to_block);
    event.set_iterations(checked_cast<u4>(iterations));
    event.commit();
  }

src/hotspot/share/runtime/safepoint.cpp:

  _current_jni_active_count = 0;

  // Set number of threads to wait for
  _waiting_to_block = nof_threads;

  jlong safepoint_limit_time = 0;
  if (SafepointTimeout) {
    // Set the limit time, so that it can be compared to see if this has taken
    // too long to complete.
    safepoint_limit_time = SafepointTracing::start_of_safepoint() + (jlong)(SafepointTimeoutDelay * NANOSECS_PER_MILLISEC);
    timeout_error_printed = false;
  }

  EventSafepointStateSynchronization sync_event;
  int initial_running = 0;

  // Arms the safepoint, _current_jni_active_count and _waiting_to_block must be set before.
  log_trace(safepoint)("Arming safepoint using %s wait barrier", _wait_barrier->description());
  arm_safepoint();

  // Will spin until all threads are safe.
  int iterations = synchronize_threads(safepoint_limit_time, nof_threads, &initial_running);
  assert(_waiting_to_block == 0, "No thread should be running");

#ifndef PRODUCT

Event configuration settings across JFR profiles
Configuration enabled threshold
default false 10 ms
profiling false 0 ms

Event fields with their types and descriptions
Field Type Description
safepointId ulong Safepoint Identifier
initialThreadCount int Initial Threads The number of threads running at the beginning of state check
runningThreadCount int Running Threads The number of threads still running
iterations int Iterations Number of state check iterations

Examples 3
Example event data values and properties
initialThreadCount int
5
iterations int
5
runningThreadCount int
0
safepointId ulong
531
startTime long: millis
466440989446
Example event data values and properties
initialThreadCount int
0
iterations int
1
runningThreadCount int
0
safepointId ulong
1595
startTime long: millis
460969452042
Example event data values and properties
initialThreadCount int
0
iterations int
1
runningThreadCount int
0
safepointId ulong
73
startTime long: millis
1902582303

SafepointEnd

startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime / Safepoint

Safepointing end

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/safepoint.cpp:

                                             uint64_t safepoint_id,
                                             int initial_number_of_threads,
                                             int threads_waiting_to_block,
                                             int iterations) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.set_initialThreadCount(initial_number_of_threads);
    event.set_runningThreadCount(threads_waiting_to_block);
    event.set_iterations(checked_cast<u4>(iterations));
    event.commit();
  }
}

static void post_safepoint_end_event(EventSafepointEnd& event, uint64_t safepoint_id) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.commit();
  }
}

// SafepointCheck
SafepointStateTracker::SafepointStateTracker(uint64_t safepoint_id, bool at_safepoint)
  : _safepoint_id(safepoint_id), _at_safepoint(at_safepoint) {}

bool SafepointStateTracker::safepoint_state_changed() {

src/hotspot/share/runtime/safepoint.cpp:

  // Release threads lock, so threads can be created/destroyed again.
  Threads_lock->unlock();

  // Wake threads after local state is correctly set.
  _wait_barrier->disarm();
}

// Wake up all threads, so they are ready to resume execution after the safepoint
// operation has been carried out
void SafepointSynchronize::end() {
  assert(Threads_lock->owned_by_self(), "must hold Threads_lock");
  SafepointTracing::leave();

  EventSafepointEnd event;
  assert(Thread::current()->is_VM_thread(), "Only VM thread can execute a safepoint");

  log_trace(safepoint)("Disarming safepoint");
  disarm_safepoint();

  log_trace(safepoint)("Resuming GC threads");
  Universe::heap()->safepoint_synchronize_end();

  SafepointTracing::end();

  post_safepoint_end_event(event, safepoint_id());

Event configuration settings across JFR profiles
Configuration enabled threshold
default false 10 ms
profiling false 0 ms

Event fields with their types and descriptions
Field Type Description
safepointId ulong Safepoint Identifier

Examples 3
Example event data values and properties
safepointId ulong
1555
startTime long: millis
453269713095
Example event data values and properties
safepointId ulong
76
startTime long: millis
1953713263
Example event data values and properties
safepointId ulong
569
startTime long: millis
495962452421

SafepointLatency

throttle startTime duration eventThread stackTrace 25 27 28

Category: Java Virtual Machine / Runtime / Safepoint

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

The delay for a thread to reach its next safepoint poll instruction after receiving an asynchronous sampling interrupt

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/sampling/jfrThreadSampling.cpp:

static inline void send_sample_event(const JfrTicks& start_time, const JfrTicks& end_time, traceid sid, traceid tid) {
  EventType event(UNTIMED);
  event.set_starttime(start_time);
  event.set_endtime(end_time);
  event.set_sampledThread(tid);
  event.set_state(static_cast<u8>(JavaThreadStatus::RUNNABLE));
  event.set_stackTrace(sid);
  event.commit();
}

static inline void send_safepoint_latency_event(const JfrSampleRequest& request, const JfrTicks& end_time, traceid sid, const JavaThread* jt) {
  assert(jt != nullptr, "invariant");
  assert(!jt->jfr_thread_local()->has_cached_stack_trace(), "invariant");
  EventSafepointLatency event(UNTIMED);
  event.set_starttime(request._sample_ticks);
  event.set_endtime(end_time);
  if (event.should_commit()) {
    event.set_threadState(_thread_in_Java);
    jt->jfr_thread_local()->set_cached_stack_trace_id(sid);
    event.commit();
    jt->jfr_thread_local()->clear_cached_stack_trace();
  }
}

static inline bool is_interpreter(const JfrSampleRequest& request) {

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold throttle
default false true 0 ms off
profiling false false 0 ms off

Event fields with their types and descriptions
Field Type Description
threadState VMThreadState VM Thread State

Examples 3
Example event data values and properties
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
82
lineNumber int
331
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
2
name string
putUncheckedLong
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/jfr/internal/event/EventWriter
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.jfr
name string
jdk.jfr
version string
25.0.4.1
name string
jdk/jfr/internal/event
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
453588652371
threadState VMThreadState
_thread_in_Java
Example event data values and properties
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
25
lineNumber int
446
method Method
descriptor string
(I)I
hidden boolean
false
modifiers int
8
name string
hotMethod2
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
1507429694
threadState VMThreadState
_thread_in_Java
Example event data values and properties
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
15
lineNumber int
278
method Method
descriptor string
([D)Lbreeze/linalg/DenseVector;
hidden boolean
false
modifiers int
1
name string
apply$mDc$sp
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
breeze/linalg/DenseVector$
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
448271345882
threadState VMThreadState
_thread_in_Java

ExecuteVMOperation

default profiling startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime

Execution of a VM Operation

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/vmThread.cpp:

  // Wait until VM thread is terminated
  // Note: it should be OK to use Terminator_lock here. But this is called
  // at a very delicate time (VM shutdown) and we are operating in non- VM
  // thread at Safepoint. It's safer to not share lock with other threads.
  {
    MonitorLocker ml(_terminate_lock, Mutex::_no_safepoint_check_flag);
    while (!VMThread::is_terminated()) {
      ml.wait();
    }
  }
}

static void post_vm_operation_event(EventExecuteVMOperation* event, VM_Operation* op) {
  assert(event != nullptr, "invariant");
  assert(op != nullptr, "invariant");
  const bool evaluate_at_safepoint = op->evaluate_at_safepoint();
  event->set_operation(op->type());
  event->set_safepoint(evaluate_at_safepoint);
  event->set_blocking(true);
  event->set_caller(JFR_THREAD_ID(op->calling_thread()));
  event->set_safepointId(evaluate_at_safepoint ? SafepointSynchronize::safepoint_id() : 0);
  event->commit();
}

void VMThread::evaluate_operation(VM_Operation* op) {
  ResourceMark rm;

  {
    PerfTraceTime vm_op_timer(perf_accumulated_vm_operation_time());
    HOTSPOT_VMOPS_BEGIN(
                     (char*) op->name(), strlen(op->name()),
                     op->evaluate_at_safepoint() ? 0 : 1);

    EventExecuteVMOperation event;
    VMThreadCPUTimeScope CPUTimeScope(this, op->is_gc_operation());
    op->evaluate();
    if (event.should_commit()) {
      post_vm_operation_event(&event, op);
    }

    HOTSPOT_VMOPS_END(
                     (char*) op->name(), strlen(op->name()),
                     op->evaluate_at_safepoint() ? 0 : 1);
  }
}

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 10 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
operation VMOperationType Operation
safepoint boolean At Safepoint If the operation occurred at a safepoint
blocking boolean Caller Blocked If the calling thread was blocked until the operation was complete
caller Thread Caller Thread requesting operation. If non-blocking, will be set to 0 indicating thread is unknown
safepointId ulong Safepoint Identifier The safepoint (if any) under which this operation was completed

Examples 3
Example event data values and properties
blocking boolean
true
caller Thread
group ThreadGroup
null
javaName string
null
javaThreadId long
0
osName string
G1 Main Marker
osThreadId long
2537
virtual boolean
false
operation VMOperationType
G1PauseRemark
safepoint boolean
true
safepointId ulong
1608
startTime long: millis
462792322527
Example event data values and properties
blocking boolean
true
caller Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
pool-1-thread-1
javaThreadId long
34
osName string
pool-1-thread-1
osThreadId long
5044
virtual boolean
false
operation VMOperationType
G1CollectForAllocation
safepoint boolean
true
safepointId ulong
69
startTime long: millis
1862393691
Example event data values and properties
blocking boolean
true
caller Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
2151
virtual boolean
false
operation VMOperationType
HandshakeAllThreads
safepoint boolean
false
safepointId ulong
0
startTime long: millis
491496789568

Shutdown

default profiling startTime eventThread stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

JVM shutting down

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/prims/jvm.cpp:

JVM_ENTRY(jstring, JVM_GetTemporaryDirectory(JNIEnv *env))
  HandleMark hm(THREAD);
  const char* temp_dir = os::get_temp_directory();
  Handle h = java_lang_String::create_from_platform_dependent_str(temp_dir, CHECK_NULL);
  return (jstring) JNIHandles::make_local(THREAD, h());
JVM_END


// java.lang.Runtime /////////////////////////////////////////////////////////////////////////

extern volatile jint vm_created;

JVM_ENTRY_NO_ENV(void, JVM_BeforeHalt())
  EventShutdown event;
  if (event.should_commit()) {
    event.set_reason("Shutdown requested from Java");
    event.commit();
  }
JVM_END


JVM_ENTRY_NO_ENV(void, JVM_Halt(jint code))
  before_exit(thread, true);
  vm_exit(code);
JVM_END

src/hotspot/share/runtime/threads.cpp:

  // Wait until we are the last non-daemon thread to execute, or
  // if we are a daemon then wait until the last non-daemon thread has
  // executed.
  bool daemon = java_lang_Thread::is_daemon(thread->threadObj());
  int expected = daemon ? 0 : 1;
  {
    MonitorLocker nu(Threads_lock);
    while (Threads::number_of_non_daemon_threads() > expected)
      // This wait should make safepoint checks, wait without a timeout.
      nu.wait(0);
  }

  EventShutdown e;
  if (e.should_commit()) {
    e.set_reason("No remaining non-daemon Java threads");
    e.commit();
  }

  // Hang forever on exit if we are reporting an error.
  if (ShowMessageBoxOnError && VMError::is_error_reported()) {
    os::infinite_sleep();
  }
  os::wait_for_keypress_at_exit();

src/hotspot/share/jfr/recorder/repository/jfrEmergencyDump.cpp:

  void transition_to_native() {
    if (_jt != nullptr) {
      assert(_jt->thread_state() == _thread_in_vm, "invariant");
      _jt->set_thread_state(_thread_in_native);
    }
  }
};

static void post_events(bool exception_handler, bool oom, Thread * thread) {
  if (exception_handler) {
    EventShutdown e;
    e.set_reason(oom ? "CrashOnOutOfMemoryError" : "VM Error");
    e.commit();
  }
  EventDumpReason event;
  event.set_reason(exception_handler && oom ? "CrashOnOutOfMemoryError" : exception_handler ? "Crash" : "Out of Memory");
  event.set_recordingId(-1);
  event.commit();
}

static volatile traceid _jfr_shutdown_tid = 0;

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default true true
profiling true true

Event fields with their types and descriptions
Field Type Description
reason string Reason Reason for JVM shutdown

Examples 3
Example event data values and properties
reason string
No remaining non-daemon Java threads
stackTrace StackTrace
null
startTime long: millis
500177444641
Example event data values and properties
reason string
No remaining non-daemon Java threads
stackTrace StackTrace
null
startTime long: millis
510390931826
Example event data values and properties
reason string
No remaining non-daemon Java threads
stackTrace StackTrace
null
startTime long: millis
25440309651

SymbolTableStatistics

profiling startTime duration every chunk 13 17 21 25 27 28

Category: Java Virtual Machine / Runtime / Tables

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  event.set_entryCount(statistics._number_of_entries);
  event.set_totalFootprint(statistics._total_footprint);
  event.set_bucketCountMaximum(statistics._maximum_bucket_size);
  event.set_bucketCountAverage(statistics._average_bucket_size);
  event.set_bucketCountVariance(statistics._variance_of_bucket_size);
  event.set_bucketCountStandardDeviation(statistics._stddev_of_bucket_size);
  event.set_insertionRate(statistics._add_rate);
  event.set_removalRate(statistics._remove_rate);
  event.commit();
}

TRACE_REQUEST_FUNC(SymbolTableStatistics) {
  TableStatistics statistics = SymbolTable::get_table_statistics();
  emit_table_statistics<EventSymbolTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(StringTableStatistics) {
  TableStatistics statistics = StringTable::get_table_statistics();
  emit_table_statistics<EventStringTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(CompilerStatistics) {
  EventCompilerStatistics event;
  event.set_compileCount(CompileBroker::get_total_compile_count());
  event.set_bailoutCount(CompileBroker::get_total_bailout_count());

Event configuration settings across JFR profiles
Configuration enabled period
default false 10 s
profiling true 10 s

Event fields with their types and descriptions
Field Type Description
bucketCount ulong Bucket Count Number of buckets
entryCount ulong Entry Count Number of all entries
totalFootprint ulong: bytes Total Footprint Total memory footprint (the table itself plus all of the entries)
bucketCountMaximum ulong Maximum Bucket Count The maximum bucket length (entries in a single bucket)
bucketCountAverage float Average Bucket Count The average bucket length
bucketCountVariance float Bucket Count Variance How far bucket lengths are spread out from their average value
bucketCountStandardDeviation float Bucket Count Standard Deviation How far bucket lengths are spread out from their mean (expected) value
insertionRate float Insertion Rate How many items were added since last event (per second)
removalRate float Removal Rate How many items were removed since last event (per second)

Examples 3
Example event data values and properties
bucketCount ulong
131072
bucketCountAverage float
4.8545
bucketCountMaximum ulong
17
bucketCountStandardDeviation float
2.2083516
bucketCountVariance float
4.876817
entryCount ulong
636289
insertionRate float
22.170702
removalRate float
0.23754323
startTime long: millis
461346238684
totalFootprint ulong: bytes
70741888
Example event data values and properties
bucketCount ulong
32768
bucketCountAverage float
1.1372681
bucketCountMaximum ulong
7
bucketCountStandardDeviation float
1.0591999
bucketCountVariance float
1.1219045
entryCount ulong
37266
insertionRate float
33226.0
removalRate float
2363.0
startTime long: millis
10587411763
totalFootprint ulong: bytes
2451824
Example event data values and properties
bucketCount ulong
131072
bucketCountAverage float
5.2180862
bucketCountMaximum ulong
17
bucketCountStandardDeviation float
2.2896307
bucketCountVariance float
5.2424088
entryCount ulong
683945
insertionRate float
1670.971
removalRate float
4.9770145
startTime long: millis
484191861551
totalFootprint ulong: bytes
74573568

StringTableStatistics

profiling startTime duration every chunk 13 17 21 25 27 28

Category: Java Virtual Machine / Runtime / Tables

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  event.set_bucketCountStandardDeviation(statistics._stddev_of_bucket_size);
  event.set_insertionRate(statistics._add_rate);
  event.set_removalRate(statistics._remove_rate);
  event.commit();
}

TRACE_REQUEST_FUNC(SymbolTableStatistics) {
  TableStatistics statistics = SymbolTable::get_table_statistics();
  emit_table_statistics<EventSymbolTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(StringTableStatistics) {
  TableStatistics statistics = StringTable::get_table_statistics();
  emit_table_statistics<EventStringTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(CompilerStatistics) {
  EventCompilerStatistics event;
  event.set_compileCount(CompileBroker::get_total_compile_count());
  event.set_bailoutCount(CompileBroker::get_total_bailout_count());
  event.set_invalidatedCount(CompileBroker::get_total_invalidated_count());
  event.set_osrCompileCount(CompileBroker::get_total_osr_compile_count());
  event.set_standardCompileCount(CompileBroker::get_total_standard_compile_count());
  event.set_osrBytesCompiled(CompileBroker::get_sum_osr_bytes_compiled());
  event.set_standardBytesCompiled(CompileBroker::get_sum_standard_bytes_compiled());

Event configuration settings across JFR profiles
Configuration enabled period
default false 10 s
profiling true 10 s

Event fields with their types and descriptions
Field Type Description
bucketCount ulong Bucket Count Number of buckets
entryCount ulong Entry Count Number of all entries
totalFootprint ulong: bytes Total Footprint Total memory footprint (the table itself plus all of the entries)
bucketCountMaximum ulong Maximum Bucket Count The maximum bucket length (entries in a single bucket)
bucketCountAverage float Average Bucket Count The average bucket length
bucketCountVariance float Bucket Count Variance How far bucket lengths are spread out from their average value
bucketCountStandardDeviation float Bucket Count Standard Deviation How far bucket lengths are spread out from their mean (expected) value
insertionRate float Insertion Rate How many items were added since last event (per second)
removalRate float Removal Rate How many items were removed since last event (per second)

Examples 3
Example event data values and properties
bucketCount ulong
65536
bucketCountAverage float
1.9975128
bucketCountMaximum ulong
12
bucketCountStandardDeviation float
1.4111167
bucketCountVariance float
1.9912505
entryCount ulong
130909
insertionRate float
517.8247
removalRate float
37.900593
startTime long: millis
499123740200
totalFootprint ulong: bytes
14213368
Example event data values and properties
bucketCount ulong
65536
bucketCountAverage float
0.096191406
bucketCountMaximum ulong
3
bucketCountStandardDeviation float
0.31053114
bucketCountVariance float
0.09642959
entryCount ulong
6304
insertionRate float
5518.0
removalRate float
27.0
startTime long: millis
10588926954
totalFootprint ulong: bytes
1034144
Example event data values and properties
bucketCount ulong
65536
bucketCountAverage float
1.935669
bucketCountMaximum ulong
11
bucketCountStandardDeviation float
1.3895206
bucketCountVariance float
1.9307675
entryCount ulong
126856
insertionRate float
334.16083
removalRate float
7.0579963
startTime long: millis
484226800566
totalFootprint ulong: bytes
13729352

ThreadDump

default profiling startTime duration every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

/*
 * This is left empty on purpose, having ExecutionSample as a requestable
 * is a way of getting the period. The period is passed to ThreadSampling::update_period.
 * Implementation in periodic/sampling/jfrThreadSampler.cpp.
 */
TRACE_REQUEST_FUNC(ExecutionSample) {
}
TRACE_REQUEST_FUNC(NativeMethodSample) {
}

TRACE_REQUEST_FUNC(ThreadDump) {
  ResourceMark rm;
  EventThreadDump event;
  event.set_result(JfrDcmdEvent::thread_dump());
  event.commit();
}

static int _native_library_callback(const char* name, address base, address top, void *param) {
  EventNativeLibrary event(UNTIMED);
  event.set_name(name);
  event.set_baseAddress((u8)base);
  event.set_topAddress((u8)top);
  event.set_starttime(*(JfrTicks*)param);
  event.set_endtime(*(JfrTicks*) param);

Event configuration settings across JFR profiles
Configuration enabled period
default true everyChunk
profiling true 60 s

Event fields with their types and descriptions
Field Type Description
result string Thread Dump

Examples 3
Example event data values and properties
result string
2026-09-13 00:33:27 Full thread dump OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x000055ffac5075e0, length=299, elements={ 0x00007f7b84053be0, 0x00007f7b840ca9b0, 0x00007f7b840cc5a0, 0x00007f7b840ce5e0, 0x00007f7b840d02c0, 0x00007f7b840d…
startTime long: millis
455890153171
Example event data values and properties
result string
2026-09-08 12:52:17 Full thread dump OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x00007fe3e8822930, length=52, elements={ 0x00007fe43c053c00, 0x00007fe43c141b20, 0x00007fe43c143870, 0x00007fe43c1457b0, 0x00007fe43c1474c0, 0x00007fe43c148…
startTime long: millis
488015740168
Example event data values and properties
result string
2026-09-08 12:52:53 Full thread dump OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x00007fa9c94d87d0, length=26, elements={ 0x00007fa9c8055900, 0x00007fa9c8154950, 0x00007fa9c8156810, 0x00007fa9c8158c80, 0x00007fa9c815abc0, 0x00007fa9c815c…
startTime long: millis
10588931653

NativeLibrary

default profiling startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Information about a dynamic library or other native image loaded by the JVM process

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

TRACE_REQUEST_FUNC(ExecutionSample) {
}
TRACE_REQUEST_FUNC(NativeMethodSample) {
}

TRACE_REQUEST_FUNC(ThreadDump) {
  ResourceMark rm;
  EventThreadDump event;
  event.set_result(JfrDcmdEvent::thread_dump());
  event.commit();
}

static int _native_library_callback(const char* name, address base, address top, void *param) {
  EventNativeLibrary event(UNTIMED);
  event.set_name(name);
  event.set_baseAddress((u8)base);
  event.set_topAddress((u8)top);
  event.set_starttime(*(JfrTicks*)param);
  event.set_endtime(*(JfrTicks*) param);
  event.commit();
  return 0;
}

TRACE_REQUEST_FUNC(NativeLibrary) {
  JfrTicks ts= JfrTicks::now();

Event configuration settings across JFR profiles
Configuration enabled period
default true everyChunk
profiling true everyChunk

Event fields with their types and descriptions
Field Type Description
name string Name
baseAddress ulong: address Base Address Starting address of the module
topAddress ulong: address Top Address Ending address of the module, if available

Examples 3
Example event data values and properties
baseAddress ulong: address
140617116024832
name string
/home/runner/.cache/JNA/temp/jna1604022464728405931.tmp
startTime long: millis
453049939224
topAddress ulong: address
140617120219136
Example event data values and properties
baseAddress ulong: address
140168635559936
name string
/lib/x86_64-linux-gnu/librt.so.1
startTime long: millis
448951582556
topAddress ulong: address
140168635580416
Example event data values and properties
baseAddress ulong: address
140367330680832
name string
/lib/x86_64-linux-gnu/librt.so.1
startTime long: millis
15623161134
topAddress ulong: address
140367330701312

NativeLibraryLoad

default profiling startTime duration eventThread stackTrace 22 25 27 28

Category: Java Virtual Machine / Runtime

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Information about a dynamic library or other native image load operation

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/support/jfrNativeLibraryLoadEvent.cpp:

/*
 * The JfrTicks value is heap allocated inside an object of type JfrTicksWrapper.
 * The reason is that a raw value object of type Ticks is not possible at this
 * location because this code runs as part of early VM bootstrap, at a moment
 * where Ticks support is not yet initialized.
 */
template <typename EventType>
static inline JfrTicksWrapper* allocate_start_time() {
  return EventType::is_enabled() ? new JfrTicksWrapper() : nullptr;
}

NativeLibraryLoadEvent::NativeLibraryLoadEvent(const char* name, void** result) : JfrNativeLibraryEventBase(name), _result(result), _fp_env_correction_attempt(false), _fp_env_correction_success(false) {
  assert(_result != nullptr, "invariant");
  _start_time = allocate_start_time<EventNativeLibraryLoad>();
}

bool NativeLibraryLoadEvent::success() const {
  return *_result != nullptr;
}

NativeLibraryUnloadEvent::NativeLibraryUnloadEvent(const char* name) : JfrNativeLibraryEventBase(name), _result(false) {
  _start_time = allocate_start_time<EventNativeLibraryUnload>();
}

bool NativeLibraryUnloadEvent::success() const {
  return _result;
}

void NativeLibraryUnloadEvent::set_result(bool result) {
  _result = result;
}

static void set_additional_data(EventNativeLibraryLoad& event, const NativeLibraryLoadEvent& helper) {
  event.set_fpuCorrectionAttempt(helper.get_fp_env_correction_attempt());
  event.set_fpuCorrectionSuccess(helper.get_fp_env_correction_success());
}

static void set_additional_data(EventNativeLibraryUnload& event, const NativeLibraryUnloadEvent& helper) {
  // no additional entries atm. for the unload event
}

template <typename EventType, typename HelperType>
static void commit(const HelperType& helper) {
  if (!helper.has_start_time()) {

src/hotspot/share/jfr/support/jfrNativeLibraryLoadEvent.cpp:

  assert(thread != nullptr, "invariant");
  if (thread->is_Java_thread()) {
    JavaThread* jt = JavaThread::cast(thread);
    if (jt->thread_state() == _thread_in_native) {
      // For a JavaThread to take a JFR stacktrace, it must be in _thread_in_vm. Can safepoint here.
      MACOS_AARCH64_ONLY(ThreadWXEnable __wx(WXWrite, jt));
      ThreadInVMfromNative transition(jt);
      event.commit();
      return;
    }
    // If a thread comes here still _thread_in_Java, which can happen for example
    // when loading the disassembler library in response to traps in JIT code - all is ok.
    // Since there is no ljf, an event will be committed without a stacktrace.
  }
  event.commit();
}

NativeLibraryLoadEvent::~NativeLibraryLoadEvent() {
  commit<EventNativeLibraryLoad>(*this);
}

NativeLibraryUnloadEvent::~NativeLibraryUnloadEvent() {
  commit<EventNativeLibraryUnload>(*this);
}

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 0 ms
profiling true true 0 ms

Event fields with their types and descriptions
Field Type Description
name string Name
success boolean Success Success or failure of the load operation
errorMessage string Error Message In case of a load error, error description
fpuCorrectionAttempt boolean 23+ FPU Environment Correction In case of IEEE conformance issues we might reset the FP environment
fpuCorrectionSuccess boolean 23+ FPU Environment Correction Result Stores the result in the case of an FP environment correction

Examples 3
Example event data values and properties
errorMessage string
null
fpuCorrectionAttempt boolean
false
fpuCorrectionSuccess boolean
false
name string
/opt/hostedtoolcache/Java_SapMachine_jdk/25.0.4-1/x64/lib/libinstrument.so
stackTrace StackTrace
null
startTime long: millis
554943395
success boolean
true
Example event data values and properties
errorMessage string
null
fpuCorrectionAttempt boolean
false
fpuCorrectionSuccess boolean
false
name string
/tmp/libzstd-jni-1.5.6-74059320827024888928.so
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljdk/internal/loader/NativeLibraries$NativeLibraryImpl;Ljava/lang/String;ZZ)Z
hidden boolean
false
modifiers int
266
name string
load
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/loader/NativeLibraries
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
type FrameType
Native
…
truncated boolean
true
startTime long: millis
492313304537
success boolean
true
Example event data values and properties
errorMessage string
null
fpuCorrectionAttempt boolean
false
fpuCorrectionSuccess boolean
false
name string
/tmp/libzstd-jni-1.5.6-715861439701291658003.so
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljdk/internal/loader/NativeLibraries$NativeLibraryImpl;Ljava/lang/String;ZZ)Z
hidden boolean
false
modifiers int
266
name string
load
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/loader/NativeLibraries
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
type FrameType
Native
…
truncated boolean
true
startTime long: millis
499888190532
success boolean
true

NativeLibraryUnload

default profiling startTime duration eventThread stackTrace 22 25 27 28

Category: Java Virtual Machine / Runtime

Information about a dynamic library or other native image unload operation

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/support/jfrNativeLibraryLoadEvent.cpp:

static inline JfrTicksWrapper* allocate_start_time() {
  return EventType::is_enabled() ? new JfrTicksWrapper() : nullptr;
}

NativeLibraryLoadEvent::NativeLibraryLoadEvent(const char* name, void** result) : JfrNativeLibraryEventBase(name), _result(result), _fp_env_correction_attempt(false), _fp_env_correction_success(false) {
  assert(_result != nullptr, "invariant");
  _start_time = allocate_start_time<EventNativeLibraryLoad>();
}

bool NativeLibraryLoadEvent::success() const {
  return *_result != nullptr;
}

NativeLibraryUnloadEvent::NativeLibraryUnloadEvent(const char* name) : JfrNativeLibraryEventBase(name), _result(false) {
  _start_time = allocate_start_time<EventNativeLibraryUnload>();
}

bool NativeLibraryUnloadEvent::success() const {
  return _result;
}

void NativeLibraryUnloadEvent::set_result(bool result) {
  _result = result;
}

static void set_additional_data(EventNativeLibraryLoad& event, const NativeLibraryLoadEvent& helper) {
  event.set_fpuCorrectionAttempt(helper.get_fp_env_correction_attempt());
  event.set_fpuCorrectionSuccess(helper.get_fp_env_correction_success());
}

static void set_additional_data(EventNativeLibraryUnload& event, const NativeLibraryUnloadEvent& helper) {
  // no additional entries atm. for the unload event
}

template <typename EventType, typename HelperType>
static void commit(const HelperType& helper) {
  if (!helper.has_start_time()) {
    return;
  }
  EventType event(UNTIMED);
  event.set_endtime(JfrTicks::now());
  event.set_starttime(*helper.start_time());

src/hotspot/share/jfr/support/jfrNativeLibraryLoadEvent.cpp:

  assert(thread != nullptr, "invariant");
  if (thread->is_Java_thread()) {
    JavaThread* jt = JavaThread::cast(thread);
    if (jt->thread_state() == _thread_in_native) {
      // For a JavaThread to take a JFR stacktrace, it must be in _thread_in_vm. Can safepoint here.
      MACOS_AARCH64_ONLY(ThreadWXEnable __wx(WXWrite, jt));
      ThreadInVMfromNative transition(jt);
      event.commit();
      return;
    }
    // If a thread comes here still _thread_in_Java, which can happen for example
    // when loading the disassembler library in response to traps in JIT code - all is ok.
    // Since there is no ljf, an event will be committed without a stacktrace.
  }
  event.commit();
}

NativeLibraryLoadEvent::~NativeLibraryLoadEvent() {
  commit<EventNativeLibraryLoad>(*this);
}

NativeLibraryUnloadEvent::~NativeLibraryUnloadEvent() {
  commit<EventNativeLibraryUnload>(*this);
}

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 0 ms
profiling true true 0 ms

Event fields with their types and descriptions
Field Type Description
name string Name
success boolean Success Success or failure of the unload operation
errorMessage string Error Message In case of an unload error, error description

ModuleRequire

default profiling startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime / Modules

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

A directed edge representing a dependency

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrModuleEvent.cpp:

   ModuleDependencyClosure(const ModuleEntry* module, EventFunc ef) : ModuleEventCallbackClosure(ef), _module(module) {}
   void do_module(ModuleEntry* entry);
};

class ModuleExportClosure : public ModuleEventCallbackClosure {
 private:
  const PackageEntry* const _package;
 public:
  ModuleExportClosure(const PackageEntry* pkg, EventFunc ef) : ModuleEventCallbackClosure(ef), _package(pkg) {}
  void do_module(ModuleEntry* entry);
};

static void write_module_dependency_event(const void* from_module, const ModuleEntry* to_module) {
  EventModuleRequire event(UNTIMED);
  event.set_starttime(invocation_time);
  event.set_endtime(invocation_time);
  event.set_source((const ModuleEntry*)from_module);
  event.set_requiredModule(to_module);
  event.commit();
}

static void write_module_export_event(const void* package, const ModuleEntry* qualified_export) {
  EventModuleExport event(UNTIMED);
  event.set_starttime(invocation_time);
  event.set_endtime(invocation_time);

Event configuration settings across JFR profiles
Configuration enabled period
default true endChunk
profiling true endChunk

Event fields with their types and descriptions
Field Type Description
source Module Source Module
requiredModule Module Required Module

Examples 3
Example event data values and properties
requiredModule Module
classLoader ClassLoader
name string
platform
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$PlatformClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
jrt:/java.compiler
name string
java.compiler
version string
25.0.4.1
source Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
jrt:/jdk.jdeps
name string
jdk.jdeps
version string
25.0.4.1
startTime long: millis
454658652535
Example event data values and properties
requiredModule Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
source Module
classLoader ClassLoader
name string
platform
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$PlatformClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
jrt:/jdk.httpserver
name string
jdk.httpserver
version string
25.0.4.1
startTime long: millis
7832187786
Example event data values and properties
requiredModule Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
source Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
jdk.proxy2
version string
null
startTime long: millis
448951600733

ModuleExport

profiling startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime / Modules

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrModuleEvent.cpp:

  void do_module(ModuleEntry* entry);
};

static void write_module_dependency_event(const void* from_module, const ModuleEntry* to_module) {
  EventModuleRequire event(UNTIMED);
  event.set_starttime(invocation_time);
  event.set_endtime(invocation_time);
  event.set_source((const ModuleEntry*)from_module);
  event.set_requiredModule(to_module);
  event.commit();
}

static void write_module_export_event(const void* package, const ModuleEntry* qualified_export) {
  EventModuleExport event(UNTIMED);
  event.set_starttime(invocation_time);
  event.set_endtime(invocation_time);
  event.set_exportedPackage((const PackageEntry*)package);
  event.set_targetModule(qualified_export);
  event.commit();
}

void ModuleDependencyClosure::do_module(ModuleEntry* to_module) {
  assert_locked_or_safepoint(Module_lock);
  assert(to_module != nullptr, "invariant");
  assert(_module != nullptr, "invariant");

Event configuration settings across JFR profiles
Configuration enabled period
default false endChunk
profiling true endChunk

Event fields with their types and descriptions
Field Type Description
exportedPackage Package Exported Package
targetModule Module Target Module Module to which the package is qualifiedly exported. If null or N/A, the package is unqualifiedly exported

Examples 3
Example event data values and properties
exportedPackage Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/hadoop/shaded/org/apache/commons/lang3
startTime long: millis
454658924545
targetModule Module
null
Example event data values and properties
exportedPackage Package
exported boolean
true
module Module
classLoader ClassLoader
name string
platform
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$PlatformClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
jrt:/jdk.sapext
name string
jdk.sapext
version string
25.0.4.1
name string
com/sap/jdk/ext/util
startTime long: millis
448951948567
targetModule Module
null
Example event data values and properties
exportedPackage Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.rmi
name string
java.rmi
version string
25.0.4.1
name string
sun/rmi/server
startTime long: millis
7832224796
targetModule Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
jrt:/jdk.jconsole
name string
jdk.jconsole
version string
25.0.4.1

Java Application

ThreadStart

default profiling startTime eventThread stackTrace 11 17 21 25 27 28

Category: Java Application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/support/jfrThreadLocal.cpp:

  assert(Thread::is_starting_thread(jt), "invariant");
  assert(jt->threadObj() == nullptr, "invariant");
  assert(jt->jfr_thread_local()->_jvm_thread_id == 0, "invariant");
  jt->jfr_thread_local()->_jvm_thread_id = ThreadIdentifier::initial();
}

static void send_java_thread_start_event(JavaThread* jt) {
  assert(jt != nullptr, "invariant");
  assert(Thread::current() == jt, "invariant");
  if (!JfrJavaSupport::on_thread_start(jt)) {
    // thread is excluded
    return;
  }
  EventThreadStart event;
  traceid thread_id = JfrThreadLocal::jvm_thread_id(jt);
  assert(thread_id != 0, "invariant");
  event.set_thread(thread_id);
  event.set_parentThread(jt->jfr_thread_local()->parent_thread_id());
  event.commit();
}

void JfrThreadLocal::on_start(Thread* t) {
  JfrThreadLocal* const tl = t->jfr_thread_local();
  assert(tl != nullptr, "invariant");
  assign_thread_id(t, tl);

src/hotspot/share/jfr/support/jfrThreadLocal.cpp:

// The starter thread ensures that the startee has a valid _vm_thread_id and _contextual_id.
// This is to avoid recursion in thread assignment since accessing the java threadObj can lead
// to events being fired, a situation the starter thread can handle but not the startee.
void JfrThreadLocal::on_java_thread_start(JavaThread* starter, JavaThread* startee) {
  assert(starter != nullptr, "invariant");
  assert(startee != nullptr, "invariant");
  JfrThreadLocal* const tl = startee->jfr_thread_local();
  assign_thread_id(startee, tl);
  assert(vthread_id(startee) != 0, "invariant");
  assert(jvm_thread_id(startee) == vthread_id(startee), "invariant");
  if (JfrRecorder::is_recording() && EventThreadStart::is_enabled() && EventThreadStart::is_stacktrace_enabled()) {
    // skip level 2 to skip frames Thread.start() and Thread.start0()
    startee->jfr_thread_local()->set_cached_stack_trace_id(JfrStackTraceRepository::record(starter, 2));
  }
}

void JfrThreadLocal::release(Thread* t) {
  if (has_java_event_writer()) {
    assert(t->is_Java_thread(), "invariant");
    JfrJavaSupport::destroy_global_jni_handle(java_event_writer());
    _java_event_writer = nullptr;
  }

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default true true
profiling true true

Event fields with their types and descriptions
Field Type Description
thread Thread New Java Thread
parentThread Thread Parent Java Thread

Examples 3
Example event data values and properties
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
5014
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
41
lineNumber int
550
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
socketIO
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
3313833841
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Thread-40
javaThreadId long
97
osName string
Thread-40
osThreadId long
5117
virtual boolean
false
Example event data values and properties
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
DestroyJavaVM
javaThreadId long
1971
osName string
DestroyJavaVM
osThreadId long
2151
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
53
lineNumber int
103
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
runHooks
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/ApplicationShutdownHooks
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
500185235560
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Thread-180
javaThreadId long
808
osName string
Thread-180
osThreadId long
4517
virtual boolean
false
Example event data values and properties
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
2535
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
10
lineNumber int
32
method Method
descriptor string
(Ljava/lang/Runnable;)V
hidden boolean
false
modifiers int
1
name string
execute
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
io/netty/util/concurrent/ThreadPerTaskExecutor
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/util/concurrent
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
499462451717
thread Thread
group ThreadGroup
name string
finagle/netty4/boss
parent ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
finagle/netty4/boss-1
javaThreadId long
1963
osName string
finagle/netty4/boss-1
osThreadId long
4898
virtual boolean
false

ThreadEnd

default profiling startTime eventThread 11 17 21 25 27 28

Category: Java Application

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/support/jfrThreadLocal.cpp:

  assert(t != nullptr, "invariant");
  assert(Thread::current() == t, "invariant");
  assert(!tl->is_dead(), "invariant");
  assert(tl->shelved_buffer() == nullptr, "invariant");
  tl->_dead = true;
  tl->release(t);
}

static void send_java_thread_end_event(JavaThread* jt, traceid tid) {
  assert(jt != nullptr, "invariant");
  assert(Thread::current() == jt, "invariant");
  assert(tid != 0, "invariant");
  if (JfrRecorder::is_recording()) {
    EventThreadEnd event;
    event.set_thread(tid);
    event.commit();
    ObjectSampleCheckpoint::on_thread_exit(tid);
  }
}

void JfrThreadLocal::on_exit(Thread* t) {
  assert(t != nullptr, "invariant");
  JfrThreadLocal * const tl = t->jfr_thread_local();
  assert(!tl->is_dead(), "invariant");
  if (JfrRecorder::is_recording()) {

src/hotspot/share/runtime/java.cpp:

#if INCLUDE_CDS
  ClassListWriter::write_resolved_constants();

  if (CDSConfig::is_dumping_preimage_static_archive()) {
    AOTMetaspace::dump_static_archive(thread);
  }
#endif

  // Hang forever on exit if we're reporting an error.
  if (ShowMessageBoxOnError && VMError::is_error_reported()) {
    os::infinite_sleep();
  }

  EventThreadEnd event;
  if (event.should_commit()) {
    event.set_thread(JFR_JVM_THREAD_ID(thread));
    event.commit();
  }

  JFR_ONLY(Jfr::on_vm_shutdown(false, halt);)

  // Stop the WatcherThread. We do this before disenrolling various
  // PeriodicTasks to reduce the likelihood of races.
  WatcherThread::stop();

Event configuration settings across JFR profiles
Configuration enabled
default true
profiling true

Event fields with their types and descriptions
Field Type Description
thread Thread Java Thread

Examples 3
Example event data values and properties
startTime long: millis
480345323317
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
context-cleaner-periodic-gc
javaThreadId long
1725
osName string
context-cleaner-periodic-gc
osThreadId long
4637
virtual boolean
false
Example event data values and properties
startTime long: millis
5680200883
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Thread-93
javaThreadId long
150
osName string
Thread-93
osThreadId long
5171
virtual boolean
false
Example event data values and properties
startTime long: millis
475252269963
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-storage-async-thread-pool-4
javaThreadId long
1721
osName string
block-manager-storage-async-thread-pool-4
osThreadId long
4244
virtual boolean
false

ThreadPark

default profiling startTime duration eventThread stackTrace 11 17 21 25 27 28

Category: Java Application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/prims/unsafe.cpp:

UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
  oop p = JNIHandles::resolve(obj);
  volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
  return AtomicAccess::cmpxchg(addr, e, x) == e;
} UNSAFE_END

UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
  oop p = JNIHandles::resolve(obj);
  volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
  return AtomicAccess::cmpxchg(addr, e, x) == e;
} UNSAFE_END

static void post_thread_park_event(EventThreadPark* event, const oop obj, jlong timeout_nanos, jlong until_epoch_millis) {
  assert(event != nullptr, "invariant");
  event->set_parkedClass((obj != nullptr) ? obj->klass() : nullptr);
  event->set_timeout(timeout_nanos);
  event->set_until(until_epoch_millis);
  event->set_address((obj != nullptr) ? (u8)cast_from_oop<uintptr_t>(obj) : 0);
  event->commit();
}

UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time)) {
  HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time);
  EventThreadPark event;

  JavaThreadParkedState jtps(thread, time != 0);
  thread->parker()->park(isAbsolute != 0, time);
  if (event.should_commit()) {
    const oop obj = thread->current_park_blocker();
    if (time == 0) {
      post_thread_park_event(&event, obj, min_jlong, min_jlong);
    } else {
      if (isAbsolute != 0) {
        post_thread_park_event(&event, obj, min_jlong, time);
      } else {

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 20 ms
profiling true true 10 ms

Event fields with their types and descriptions
Field Type Description
parkedClass Class Class Parked On
timeout long: nanos Park Timeout
until long: epochmillis Park Until
address ulong: address Address of Object Parked

Examples 3
Example event data values and properties
address ulong: address
30389676024
parkedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
24
name string
java/util/concurrent/locks/ReentrantLock$NonfairSync
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent/locks
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
type FrameType
Native
…
truncated boolean
false
startTime long: millis
447545100357
timeout long: nanos
-9223372036854775808
until long: epochmillis
-9223372036854775808
Example event data values and properties
address ulong: address
30362878480
parkedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionObject
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent/locks
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
type FrameType
Native
…
truncated boolean
false
startTime long: millis
453308905577
timeout long: nanos
-9223372036854775808
until long: epochmillis
-9223372036854775808
Example event data values and properties
address ulong: address
0
parkedClass Class
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
type FrameType
Native
…
truncated boolean
false
startTime long: millis
3621618138
timeout long: nanos
1000000
until long: epochmillis
-9223372036854775808

JavaMonitorEnter

default profiling startTime duration eventThread stackTrace 11 17 21 25 27 28

Category: Java Application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/objectMonitor.cpp:

    // yet appear on any queues that would get it made the successor.
    // This means that the JVMTI_EVENT_MONITOR_CONTENDED_ENTER event
    // handler cannot accidentally consume an unpark() meant for the
    // ParkEvent associated with this ObjectMonitor.
  }
}

void ObjectMonitor::enter_with_contention_mark(JavaThread* current, ObjectMonitorContentionMark &cm, bool post_jvmti_events) {
  assert(current == JavaThread::current(), "must be");
  assert(!has_owner(current), "must be");
  assert(cm._monitor == this, "must be");
  assert(!is_being_async_deflated(), "must be");

  JFR_ONLY(JfrConditionalFlush<EventJavaMonitorEnter> flush(current);)
  EventJavaMonitorEnter enter_event;
  if (enter_event.is_started()) {
    enter_event.set_monitorClass(object()->klass());
    // Set an address that is 'unique enough', such that events close in
    // time and with the same address are likely (but not guaranteed) to
    // belong to the same object.
    enter_event.set_address((uintptr_t)this);
  }
  EventVirtualThreadPinned vthread_pinned_event;

  freeze_result result;

src/hotspot/share/runtime/objectMonitor.cpp:

    assert(false, "Non-balanced monitor enter/exit!");
#endif
    return;
  }

  if (_recursions != 0) {
    _recursions--;        // this is simple recursive enter
    return;
  }

#if INCLUDE_JFR
  // get the owner's thread id for the MonitorEnter event
  // if it is enabled and the thread isn't suspended
  if (not_suspended && EventJavaMonitorEnter::is_enabled()) {
    _previous_owner_tid = JFR_THREAD_ID(current);
  }
#endif

  for (;;) {
    // If there is a successor we should release the lock as soon as
    // possible, so that the successor can acquire the lock. If there is
    // no successor, we might need to wake up a waiting thread.
    if (!has_successor()) {
      ObjectWaiter* w = AtomicAccess::load(&_entry_list);
      if (w != nullptr) {

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 20 ms
profiling true true 10 ms

Event fields with their types and descriptions
Field Type Description
monitorClass Class Monitor Class
previousOwner Thread Previous Monitor Owner
address ulong: address Monitor Address

Examples 3
Example event data values and properties
address ulong: address
140367203438016
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/jfr/internal/PlatformRecorder
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.jfr
name string
jdk.jfr
version string
25.0.4.1
name string
jdk/jfr/internal
previousOwner Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
5014
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
15
lineNumber int
495
method Method
descriptor string
()V
hidden boolean
false
modifiers int
2
name string
periodicTask
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/jfr/internal/PlatformRecorder
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.jfr
name string
jdk.jfr
version string
25.0.4.1
name string
jdk/jfr/internal
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
364639713
Example event data values and properties
address ulong: address
94556810078336
monitorClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/rpc/netty/Dispatcher
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/rpc/netty
previousOwner Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 2.0 in stage 38.0 (TID 148)
javaThreadId long
1712
osName string
Executor task launch worker for task 2.0 in stage 38.0 (TID 148)
osThreadId long
4235
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
4
lineNumber int
173
method Method
descriptor string
(Ljava/lang/String;Lorg/apache/spark/rpc/netty/InboxMessage;Lscala/Function1;)V
hidden boolean
false
modifiers int
2
name string
postMessage
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/rpc/netty/Dispatcher
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/rpc/netty
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
448391542294
Example event data values and properties
address ulong: address
140617523387200
monitorClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/memory/UnifiedMemoryManager
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/memory
previousOwner Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-storage-async-thread-pool-54
javaThreadId long
1827
osName string
block-manager-storage-async-thread-pool-54
osThreadId long
4745
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
320
lineNumber int
260
method Method
descriptor string
(Lorg/apache/spark/storage/BlockId;Lscala/collection/Iterator;Lscala/reflect/ClassTag;Lorg/apache/spark/memory/MemoryMode;Lorg/apache/spark/storage/memory/ValuesHolder;)Lscala/util/Either;
hidden boolean
false
modifiers int
2
name string
putIterator
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/storage/memory/MemoryStore
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/storage/memory
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
454252541925

JavaMonitorWait

default profiling startTime duration eventThread stackTrace 11 17 21 25 27 28

Category: Java Application

Waiting on a Java monitor

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/objectMonitor.cpp:

// Otherwise returns false and throws IllegalMonitorStateException
// (IMSE). If there is a pending exception and the specified thread
// is not the owner, that exception will be replaced by the IMSE.
bool ObjectMonitor::check_owner(TRAPS) {
  JavaThread* current = THREAD;
  int64_t cur = owner_raw();
  if (cur == owner_id_from(current)) {
    return true;
  }
  THROW_MSG_(vmSymbols::java_lang_IllegalMonitorStateException(),
             "current thread is not owner", false);
}

static void post_monitor_wait_event(EventJavaMonitorWait* event,
                                    ObjectMonitor* monitor,
                                    uint64_t notifier_tid,
                                    jlong timeout,
                                    bool timedout) {
  assert(event != nullptr, "invariant");
  assert(monitor != nullptr, "invariant");
  const Klass* monitor_klass = monitor->object()->klass();
  if (ObjectMonitor::is_jfr_excluded(monitor_klass)) {
    return;
  }
  event->set_monitorClass(monitor_klass);
  event->set_timeout(timeout);
  // Set an address that is 'unique enough', such that events close in
  // time and with the same address are likely (but not guaranteed) to
  // belong to the same object.
  event->set_address((uintptr_t)monitor);
  event->set_notifier(notifier_tid);
  event->set_timedOut(timedout);
  event->commit();
}

static void vthread_monitor_waited_event(JavaThread* current, ObjectWaiter* node, ContinuationWrapper& cont, EventJavaMonitorWait* event, jboolean timed_out) {
  // Since we might safepoint set the anchor so that the stack can we walked.
  assert(current->last_continuation() != nullptr, "");
  JavaFrameAnchor* anchor = current->frame_anchor();
  anchor->set_last_Java_sp(current->last_continuation()->entry_sp());
  anchor->set_last_Java_pc(current->last_continuation()->entry_pc());

  ContinuationWrapper::SafepointOp so(current, cont);

  JRT_BLOCK
    if (event->should_commit()) {
      long timeout = java_lang_VirtualThread::timeout(current->vthread());

src/hotspot/share/runtime/objectMonitor.cpp:

// -----------------------------------------------------------------------------
// Wait/Notify/NotifyAll
//
// Note: a subset of changes to ObjectMonitor::wait()
// will need to be replicated in complete_exit
void ObjectMonitor::wait(jlong millis, bool interruptible, TRAPS) {
  JavaThread* current = THREAD;

  assert(InitDone, "Unexpectedly not initialized");

  CHECK_OWNER();  // Throws IMSE if not owner.

  EventJavaMonitorWait wait_event;
  EventVirtualThreadPinned vthread_pinned_event;

  // check for a pending interrupt
  if (interruptible && current->is_interrupted(true) && !HAS_PENDING_EXCEPTION) {
    JavaThreadInObjectWaitState jtiows(current, millis != 0, interruptible);

    if (JvmtiExport::should_post_monitor_wait()) {
      JvmtiExport::post_monitor_wait(current, object(), millis);
    }
    // post monitor waited event. Note that this is past-tense, we are done waiting.
    if (JvmtiExport::should_post_monitor_waited()) {

src/hotspot/share/runtime/objectMonitor.cpp:

  // If this was an interrupted case, set the _interrupted boolean so that
  // once we re-acquire the monitor we know if we need to throw IE or not.
  ObjectWaiter::TStates state = node->TState;
  assert(was_notified || state == ObjectWaiter::TS_RUN,
         "was not notified and is not in the right state: state = %s",
         node->getTStateName(state));
  node->_interrupted = node->_interruptible && !was_notified && current->is_interrupted(false);

  // Post JFR and JVMTI events. If non-interruptible we are in
  // ObjectLocker case so we don't post anything.
  EventJavaMonitorWait wait_event;
  if (node->_interruptible && (wait_event.should_commit() || JvmtiExport::should_post_monitor_waited())) {
    vthread_monitor_waited_event(current, node, cont, &wait_event, !was_notified && !node->_interrupted);
  }

  // Mark that we are at reenter so that we don't call this method again.
  node->_at_reenter = true;

  // We check the state rather than was_notified because, when JVMTI
  // monitor_waited event is enabled, the notifier only unparks the waiter
  // without adding it to the entry_list.
  if (state == ObjectWaiter::TS_RUN) {

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 20 ms
profiling true true 10 ms

Event fields with their types and descriptions
Field Type Description
monitorClass Class Monitor Class Class of object waited on
notifier Thread Notifier Thread Notifying Thread
timeout long: millis Timeout Maximum wait time
timedOut boolean Timed Out Wait has been timed out
address ulong: address Monitor Address Address of object waited on

Examples 3
Example event data values and properties
address ulong: address
140165942958000
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
notifier Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 3.0 in stage 38.0 (TID 149)
javaThreadId long
1709
osName string
Executor task launch worker for task 3.0 in stage 38.0 (TID 149)
osThreadId long
4230
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
274
name string
wait0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
449433004381
timedOut boolean
false
timeout long: millis
0
Example event data values and properties
address ulong: address
94795309480480
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
notifier Thread
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
274
name string
wait0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
2728427963
timedOut boolean
true
timeout long: millis
1
Example event data values and properties
address ulong: address
140616843402656
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
notifier Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 0.0 in stage 47.0 (TID 182)
javaThreadId long
1731
osName string
Executor task launch worker for task 0.0 in stage 47.0 (TID 182)
osThreadId long
4648
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
274
name string
wait0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
454651311049
timedOut boolean
false
timeout long: millis
0

JavaMonitorNotify

startTime duration eventThread stackTrace 25 27 28

Category: Java Application

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Notifying a Java monitor

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/objectMonitor.cpp:

    // _wait_set_lock protects the wait queue, not the entry_list. We could
    // move the add-to-entry_list operation, above, outside the critical section
    // protected by _wait_set_lock. In practice that's not useful. With the
    // exception of wait() timeouts and interrupts the monitor owner
    // is the only thread that grabs _wait_set_lock. There's almost no contention
    // on _wait_set_lock so it's not profitable to reduce the length of the
    // critical section.
  }
  return did_notify;
}

static void post_monitor_notify_event(EventJavaMonitorNotify* event,
                                      ObjectMonitor* monitor,
                                      int notified_count) {
  assert(event != nullptr, "invariant");
  assert(monitor != nullptr, "invariant");
  const Klass* monitor_klass = monitor->object()->klass();
  if (ObjectMonitor::is_jfr_excluded(monitor_klass)) {
    return;
  }
  event->set_monitorClass(monitor_klass);
  // Set an address that is 'unique enough', such that events close in
  // time and with the same address are likely (but not guaranteed) to

src/hotspot/share/runtime/objectMonitor.cpp:

void ObjectMonitor::notify(TRAPS) {
  JavaThread* current = THREAD;
  CHECK_OWNER();  // Throws IMSE if not owner.
  if (_wait_set == nullptr) {
    return;
  }

  quick_notify(current);
}

void ObjectMonitor::quick_notify(JavaThread* current) {
  assert(has_owner(current), "Precondition");

  EventJavaMonitorNotify event;
  DTRACE_MONITOR_PROBE(notify, this, object(), current);
  int tally = notify_internal(current) ? 1 : 0;

  if ((tally > 0) && event.should_commit()) {
    post_monitor_notify_event(&event, this, /* notified_count = */ tally);
  }
}

// notifyAll() transfers the waiters one-at-a-time from the waitset to
// the entry_list. If the waitset is "ABCD" (where A was added first
// and D last) and the entry_list is ->X->Y->Z. After a notifyAll()

src/hotspot/share/runtime/objectMonitor.cpp:

void ObjectMonitor::notifyAll(TRAPS) {
  JavaThread* current = THREAD;
  CHECK_OWNER();  // Throws IMSE if not owner.
  if (_wait_set == nullptr) {
    return;
  }

  quick_notifyAll(current);
}

void ObjectMonitor::quick_notifyAll(JavaThread* current) {
  assert(has_owner(current), "Precondition");

  EventJavaMonitorNotify event;
  DTRACE_MONITOR_PROBE(notifyAll, this, object(), current);
  int tally = 0;
  while (_wait_set != nullptr) {
    if (notify_internal(current)) {
      tally++;
    }
  }

  if ((tally > 0) && event.should_commit()) {
    post_monitor_notify_event(&event, this, /* notified_count = */ tally);
  }

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default false true 0 ms
profiling false true 0 ms

Event fields with their types and descriptions
Field Type Description
monitorClass Class Monitor Class Class of object waited on
notifiedCount uint Notified Threads Number of actually notified threads
address ulong: address Monitor Address Address of object waited on

Examples 3
Example event data values and properties
address ulong: address
94895174441632
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
java/lang/ref/ReferenceQueue$Lock
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang/ref
notifiedCount uint
1
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
273
name string
notifyAll
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
461062597700
Example event data values and properties
address ulong: address
140367200240048
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Thread
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
notifiedCount uint
1
stackTrace StackTrace
null
startTime long: millis
2254675833
Example event data values and properties
address ulong: address
140168510764384
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
notifiedCount uint
1
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
273
name string
notifyAll
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
449679133408

JavaMonitorInflate

startTime duration eventThread stackTrace 11 17 21 25 27 28

Category: Java Application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/synchronizer.cpp:

static void log_inflate(Thread* current, oop object, ObjectSynchronizer::InflateCause cause) {
  if (log_is_enabled(Trace, monitorinflation)) {
    ResourceMark rm(current);
    log_trace(monitorinflation)("inflate: object=" INTPTR_FORMAT ", mark="
                                INTPTR_FORMAT ", type='%s' cause=%s", p2i(object),
                                object->mark().value(), object->klass()->external_name(),
                                ObjectSynchronizer::inflate_cause_name(cause));
  }
}

static void post_monitor_inflate_event(EventJavaMonitorInflate* event,
                                       const oop obj,
                                       ObjectSynchronizer::InflateCause cause) {
  assert(event != nullptr, "invariant");
  const Klass* monitor_klass = obj->klass();
  if (ObjectMonitor::is_jfr_excluded(monitor_klass)) {
    return;
  }
  event->set_monitorClass(monitor_klass);
  event->set_address((uintptr_t)(void*)obj);
  event->set_cause((u1)cause);
  event->commit();
}

ObjectMonitor* ObjectSynchronizer::get_or_insert_monitor(oop object, JavaThread* current, ObjectSynchronizer::InflateCause cause) {
  assert(UseObjectMonitorTable, "must be");

  EventJavaMonitorInflate event;

  bool inserted;
  ObjectMonitor* monitor = get_or_insert_monitor_from_table(object, &inserted);

  if (inserted) {
    log_inflate(current, object, cause);
    if (event.should_commit()) {
      post_monitor_inflate_event(&event, object, cause);
    }

    // The monitor has an anonymous owner so it is safe from async deflation.

src/hotspot/share/runtime/synchronizer.cpp:

ObjectMonitor* ObjectSynchronizer::inflate_into_object_header(oop object, ObjectSynchronizer::InflateCause cause, JavaThread* locking_thread, Thread* current) {

  // The JavaThread* locking parameter requires that the locking_thread == JavaThread::current,
  // or is suspended throughout the call by some other mechanism.
  // Even with fast locking the thread might be nullptr when called from a non
  // JavaThread. (As may still be the case from FastHashCode). However it is only
  // important for the correctness of the fast locking algorithm that the thread
  // is set when called from ObjectSynchronizer::enter from the owning thread,
  // ObjectSynchronizer::enter_for from any thread, or ObjectSynchronizer::exit.
  EventJavaMonitorInflate event;

  for (;;) {
    const markWord mark = object->mark_acquire();

    // The mark can be in one of the following states:
    // *  inflated     - If the ObjectMonitor owner is anonymous and the
    //                   locking_thread owns the object lock, then we make the
    //                   locking_thread the ObjectMonitor owner and remove the
    //                   lock from the locking_thread's lock stack.
    // *  fast-locked  - Coerce it to inflated from fast-locked.
    // *  unlocked     - Aggressively inflate the object.

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default false true 0 ms
profiling false true 0 ms

Event fields with their types and descriptions
Field Type Description
monitorClass Class Monitor Class
address ulong: address Monitor Address
cause InflateCause Monitor Inflation Cause Cause of inflation

Examples 3
Example event data values and properties
address ulong: address
30603428408
cause InflateCause
Monitor Wait
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
274
name string
wait0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
456053234295
Example event data values and properties
address ulong: address
30195388696
cause InflateCause
Monitor Wait
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Thread
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
274
name string
wait0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
1860756171
Example event data values and properties
address ulong: address
33019090264
cause InflateCause
Monitor Wait
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
274
name string
wait0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
457041502824

JavaMonitorDeflate

startTime duration 25 27 28

Category: Java Application

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/objectMonitor.cpp:

    // Interference - the CAS failed because _entry_list changed. Before
    // retrying the CAS retry taking the lock as it may now be free.
    if (try_lock(current) == TryLockResult::Success) {
      assert(has_owner(current), "invariant");
      assert(!has_successor(current), "invariant");
      node->TState = ObjectWaiter::TS_RUN;
      return true;
    }
  }
}

static void post_monitor_deflate_event(EventJavaMonitorDeflate* event,
                                       const oop obj) {
  assert(event != nullptr, "invariant");
  if (obj == nullptr) {
    // Accept the case when obj was already garbage-collected.
    // Emit the event anyway, but without details.
    event->set_monitorClass(nullptr);
    event->set_address(0);
  } else {
    const Klass* monitor_klass = obj->klass();
    if (ObjectMonitor::is_jfr_excluded(monitor_klass)) {
      return;

src/hotspot/share/runtime/objectMonitor.cpp:

// as part of the protocol to make sure that the calling thread has
// not lost the race to a contending thread.
//
// The ObjectMonitor has been successfully async deflated when:
//   (contentions < 0)
// Contending threads that see that condition know to retry their operation.
//
bool ObjectMonitor::deflate_monitor(Thread* current) {
  if (is_busy()) {
    // Easy checks are first - the ObjectMonitor is busy so no deflation.
    return false;
  }

  EventJavaMonitorDeflate event;

  const oop obj = object_peek();

  if (obj == nullptr) {
    // If the object died, we can recycle the monitor without racing with
    // Java threads. The GC already broke the association with the object.
    set_owner_from_raw(NO_OWNER, DEFLATER_MARKER);
    assert(contentions() >= 0, "must be non-negative: contentions=%d", contentions());
    _contentions = INT_MIN; // minimum negative int
  } else {
    // Attempt async deflation protocol.

Event configuration settings across JFR profiles
Configuration enabled threshold
default false 0 ms
profiling false 0 ms

Event fields with their types and descriptions
Field Type Description
monitorClass Class Monitor Class Class of the object deflated. If null or N/A, the object has been garbage collected.
address ulong: address Monitor Address Address of the object deflated. If null or N/A, the object has been garbage collected.

Examples 3
Example event data values and properties
address ulong: address
0
monitorClass Class
null
startTime long: millis
605023674364
Example event data values and properties
address ulong: address
0
monitorClass Class
null
startTime long: millis
481040757678
Example event data values and properties
address ulong: address
30390375712
monitorClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
org/apache/spark/util/EventLoop$$anon$1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/util
startTime long: millis
480714758660

VirtualThreadPinned

default profiling startTime duration eventThread stackTrace 19 21 25 27 28

Category: Java Application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/prims/jvm.cpp:

    assert(!JvmtiExport::can_support_virtual_threads(), "sanity check");
    return;
  }
  assert(thread->is_disable_suspend() != (bool)enter,
         "nested or unbalanced monitor enter/exit is not allowed");
  thread->toggle_is_disable_suspend();
#endif
JVM_END

JVM_ENTRY(void, JVM_VirtualThreadPinnedEvent(JNIEnv* env, jclass ignored, jstring op))
#if INCLUDE_JFR
  freeze_result result = THREAD->last_freeze_fail_result();
  assert(result != freeze_ok, "sanity check");
  EventVirtualThreadPinned event(UNTIMED);
  event.set_starttime(THREAD->last_freeze_fail_time());
  if (event.should_commit()) {
    ResourceMark rm(THREAD);
    const char *str = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(op));
    THREAD->post_vthread_pinned_event(&event, str, result);
  }
#endif
JVM_END

JVM_ENTRY(jobject, JVM_TakeVirtualThreadListToUnblock(JNIEnv* env, jclass ignored))
  ParkEvent* parkEvent = ObjectMonitor::vthread_unparker_ParkEvent();

src/hotspot/share/runtime/javaThread.hpp:

class OSThread;

class ThreadsList;
class ThreadSafepointState;
class ThreadStatistics;

class vframeArray;
class vframe;
class javaVFrame;

class JavaThread;
typedef void (*ThreadFunction)(JavaThread*, TRAPS);

class EventVirtualThreadPinned;
class ThreadWXEnable;

class JavaThread: public Thread {
  friend class VMStructs;
  friend class WhiteBox;
  friend class ThreadsSMRSupport; // to access _threadObj for exiting_threads_oops_do
  friend class HandshakeState;
  friend class Continuation;
  friend class Threads;
  friend class ServiceThread; // for deferred OopHandle release access
 private:

src/hotspot/share/runtime/javaThread.hpp:

  bool sleep(jlong millis);
  bool sleep_nanos(jlong nanos);

  // java.lang.Thread interruption support
  void interrupt();
  bool is_interrupted(bool clear_interrupted);

#if INCLUDE_JFR
  // Support for jdk.VirtualThreadPinned event
  freeze_result last_freeze_fail_result() { return _last_freeze_fail_result; }
  Ticks& last_freeze_fail_time() { return _last_freeze_fail_time; }
  void set_last_freeze_fail_result(freeze_result result);
#endif
  void post_vthread_pinned_event(EventVirtualThreadPinned* event, const char* op, freeze_result result) NOT_JFR_RETURN();


  // This is only for use by JVMTI RawMonitorWait. It emulates the actions of
  // the Java code in Object::wait which are not present in RawMonitorWait.
  bool get_and_clear_interrupted();

private:

#ifdef MACOS_AARCH64
  friend class ThreadWXEnable;
  friend class PosixSignals;

src/hotspot/share/runtime/objectMonitor.cpp:

  assert(!has_owner(current), "must be");
  assert(cm._monitor == this, "must be");
  assert(!is_being_async_deflated(), "must be");

  JFR_ONLY(JfrConditionalFlush<EventJavaMonitorEnter> flush(current);)
  EventJavaMonitorEnter enter_event;
  if (enter_event.is_started()) {
    enter_event.set_monitorClass(object()->klass());
    // Set an address that is 'unique enough', such that events close in
    // time and with the same address are likely (but not guaranteed) to
    // belong to the same object.
    enter_event.set_address((uintptr_t)this);
  }
  EventVirtualThreadPinned vthread_pinned_event;

  freeze_result result;

  assert(current->current_pending_monitor() == nullptr, "invariant");

  ContinuationEntry* ce = current->last_continuation();
  bool is_virtual = ce != nullptr && ce->is_virtual_thread();
  if (is_virtual) {
    notify_contended_enter(current, post_jvmti_events);
    result = Continuation::try_preempt(current, ce->cont_oop(current));
    if (result == freeze_ok) {

src/hotspot/share/runtime/objectMonitor.cpp:

// -----------------------------------------------------------------------------
// Wait/Notify/NotifyAll
//
// Note: a subset of changes to ObjectMonitor::wait()
// will need to be replicated in complete_exit
void ObjectMonitor::wait(jlong millis, bool interruptible, TRAPS) {
  JavaThread* current = THREAD;

  assert(InitDone, "Unexpectedly not initialized");

  CHECK_OWNER();  // Throws IMSE if not owner.

  EventJavaMonitorWait wait_event;
  EventVirtualThreadPinned vthread_pinned_event;

  // check for a pending interrupt
  if (interruptible && current->is_interrupted(true) && !HAS_PENDING_EXCEPTION) {
    JavaThreadInObjectWaitState jtiows(current, millis != 0, interruptible);

    if (JvmtiExport::should_post_monitor_wait()) {
      JvmtiExport::post_monitor_wait(current, object(), millis);
    }
    // post monitor waited event. Note that this is past-tense, we are done waiting.
    if (JvmtiExport::should_post_monitor_waited()) {
      // Note: 'false' parameter is passed here because the

src/hotspot/share/runtime/javaThread.cpp:

  new_head->add(_scopedValueCache);
  _oop_handle_list = new_head;
  Service_lock->notify_all();
}

#if INCLUDE_JFR
void JavaThread::set_last_freeze_fail_result(freeze_result result) {
  assert(result != freeze_ok, "sanity check");
  _last_freeze_fail_result = result;
  _last_freeze_fail_time = Ticks::now();
}

// Post jdk.VirtualThreadPinned event
void JavaThread::post_vthread_pinned_event(EventVirtualThreadPinned* event, const char* op, freeze_result result) {
  assert(result != freeze_ok, "sanity check");
  if (event->should_commit()) {
    char reason[256];
    if (class_to_be_initialized() != nullptr) {
      ResourceMark rm(this);
      jio_snprintf(reason, sizeof reason, "Waited for initialization of %s by another thread",
                   class_to_be_initialized()->external_name());
      event->set_pinnedReason(reason);
    } else if (class_being_initialized() != nullptr) {
      ResourceMark rm(this);
      jio_snprintf(reason, sizeof(reason), "VM call to %s.<clinit> on stack",

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 20 ms
profiling true true 20 ms

Event fields with their types and descriptions
Field Type Description
blockingOperation string 24+ Blocking Operation
pinnedReason string 24+ Pinned Reason
carrierThread Thread 24+ Carrier Thread

ObjectAllocationInNewTLAB

startTime eventThread stackTrace 11 17 21 25 27 28

Category: Java Application

Allocation in new Thread Local Allocation Buffer

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/allocTracer.cpp:

void AllocTracer::send_allocation_outside_tlab(Klass* klass, HeapWord* obj, size_t alloc_size, JavaThread* thread) {
  JFR_ONLY(JfrAllocationTracer tracer(klass, obj, alloc_size, true, thread);)
  EventObjectAllocationOutsideTLAB event;
  if (event.should_commit()) {
    event.set_objectClass(klass);
    event.set_allocationSize(alloc_size);
    event.commit();
  }
}

void AllocTracer::send_allocation_in_new_tlab(Klass* klass, HeapWord* obj, size_t tlab_size, size_t alloc_size, JavaThread* thread) {
  JFR_ONLY(JfrAllocationTracer tracer(klass, obj, alloc_size, false, thread);)
  EventObjectAllocationInNewTLAB event;
  if (event.should_commit()) {
    event.set_objectClass(klass);
    event.set_allocationSize(alloc_size);
    event.set_tlabSize(tlab_size);
    event.commit();
  }
}

void AllocTracer::send_allocation_requiring_gc_event(size_t size, uint gcId) {
  EventAllocationRequiringGC event;
  if (event.should_commit()) {

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default false true
profiling false true

Event fields with their types and descriptions
Field Type Description
objectClass Class Object Class Class of allocated object
allocationSize ulong: bytes Allocation Size
tlabSize ulong: bytes TLAB Size

Examples 3
Example event data values and properties
allocationSize ulong: bytes
80
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[D
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
1
lineNumber int
273
method Method
descriptor string
(I)[D
hidden boolean
false
modifiers int
1
name string
newArray
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
25
name string
scala/reflect/ManifestFactory$DoubleManifest
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/reflect
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
452967990695
tlabSize ulong: bytes
1048576
Example event data values and properties
allocationSize ulong: bytes
32
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
24
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionNode
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent/locks
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
10
lineNumber int
1667
method Method
descriptor string
()Ljava/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionNode;
hidden boolean
false
modifiers int
2
name string
newConditionNode
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionObject
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent/locks
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
447750803240
tlabSize ulong: bytes
159088
Example event data values and properties
allocationSize ulong: bytes
4112
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
24
lineNumber int
494
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
allocateAndGC
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
565795062
tlabSize ulong: bytes
46168

ObjectAllocationOutsideTLAB

startTime eventThread stackTrace 11 17 21 25 27 28

Category: Java Application

Allocation outside Thread Local Allocation Buffers

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/allocTracer.cpp:

#if INCLUDE_JFR
#include "jfr/support/jfrAllocationTracer.hpp"
#endif

void AllocTracer::send_allocation_outside_tlab(Klass* klass, HeapWord* obj, size_t alloc_size, JavaThread* thread) {
  JFR_ONLY(JfrAllocationTracer tracer(klass, obj, alloc_size, true, thread);)
  EventObjectAllocationOutsideTLAB event;
  if (event.should_commit()) {
    event.set_objectClass(klass);
    event.set_allocationSize(alloc_size);
    event.commit();
  }
}

void AllocTracer::send_allocation_in_new_tlab(Klass* klass, HeapWord* obj, size_t tlab_size, size_t alloc_size, JavaThread* thread) {
  JFR_ONLY(JfrAllocationTracer tracer(klass, obj, alloc_size, false, thread);)
  EventObjectAllocationInNewTLAB event;
  if (event.should_commit()) {
    event.set_objectClass(klass);
    event.set_allocationSize(alloc_size);

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default false true
profiling false true

Event fields with their types and descriptions
Field Type Description
objectClass Class Object Class Class of allocated object
allocationSize ulong: bytes Allocation Size

Examples 3
Example event data values and properties
allocationSize ulong: bytes
4112
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
24
lineNumber int
494
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
allocateAndGC
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
560739372
Example event data values and properties
allocationSize ulong: bytes
1048592
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
6
lineNumber int
75
method Method
descriptor string
(IILjava/lang/foreign/MemorySegment;)V
hidden boolean
false
modifiers int
0
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/nio/HeapByteBuffer
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/nio
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
448808625521
Example event data values and properties
allocationSize ulong: bytes
280080
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
15
lineNumber int
3537
method Method
descriptor string
([BI)[B
hidden boolean
false
modifiers int
9
name string
copyOf
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/util/Arrays
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
type FrameType
JIT compiled
…
truncated boolean
true
startTime long: millis
453890313423

ObjectAllocationSample

throttle default profiling startTime eventThread stackTrace 16 17 21 25 27 28

Category: Java Application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/support/jfrAllocationTracer.cpp:

JfrAllocationTracer::JfrAllocationTracer(const Klass* klass, HeapWord* obj, size_t alloc_size, bool outside_tlab, JavaThread* thread) {
  if (LeakProfiler::is_running()) {
    LeakProfiler::sample(obj, alloc_size, thread);
  }
  if (EventObjectAllocationSample::is_enabled()) {
    JfrObjectAllocationSample::send_event(klass, alloc_size, outside_tlab, thread);
  }
}

src/hotspot/share/jfr/support/jfrObjectAllocationSample.cpp:

inline bool send_allocation_sample(const Klass* klass, int64_t allocated_bytes, JfrThreadLocal* tl) {
  EventObjectAllocationSample event;
  if (event.should_commit()) {
    const int64_t weight = allocated_bytes - tl->last_allocated_bytes();
    assert(weight > 0, "invariant");
    event.set_objectClass(klass);
    event.set_weight(weight);
    event.commit();
    tl->set_last_allocated_bytes(allocated_bytes);
    return true;
  }
  return false;
}

inline int64_t estimate_tlab_size_bytes(JavaThread* jt) {
  const size_t desired_tlab_size_bytes = jt->tlab().desired_size() * HeapWordSize;
  const size_t alignment_reserve_bytes = jt->tlab().alignment_reserve_in_bytes();

Event configuration settings across JFR profiles
Configuration enabled stackTrace throttle
default true true 150/s
profiling true true 300/s

Event fields with their types and descriptions
Field Type Description
objectClass Class Object Class Class of allocated object
weight long: bytes Sample Weight The relative weight of the sample. Aggregating the weights for a large number of samples, for a particular class, thread or stack trace, gives a statistically accurate representation of the allocation pressure

Examples 3
Example event data values and properties
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
24
lineNumber int
494
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
allocateAndGC
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
561153168
weight long: bytes
69904
Example event data values and properties
objectClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
breeze/linalg/DenseVector$mcD$sp
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
15
lineNumber int
278
method Method
descriptor string
([D)Lbreeze/linalg/DenseVector;
hidden boolean
false
modifiers int
1
name string
apply$mDc$sp
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
breeze/linalg/DenseVector$
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
448098588621
weight long: bytes
2992016
Example event data values and properties
objectClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
breeze/linalg/DenseVector$mcD$sp
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
35
lineNumber int
134
method Method
descriptor string
()Lbreeze/linalg/DenseVector;
hidden boolean
false
modifiers int
1
name string
copy$mcD$sp
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
breeze/linalg/DenseVector$mcD$sp
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
452967115103
weight long: bytes
1047992

MethodTrace

default profiling startTime duration eventThread stackTrace 25 27 28

Category: Java Application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void traceObjectInit(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTraceEvent.shouldCommit(duration) && JVM.getEventWriter() != null) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
    }

    public static void timingObjectInit(long startTime, long methodId) {

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void traceTimingObjectInit(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTraceEvent.shouldCommit(duration) && JVM.getEventWriter() != null) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addObjectTiming(duration);
        }

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void trace(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTraceEvent.shouldCommit(duration)) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
    }

    public static void timing(long startTime, long methodId) {

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addTiming(methodId, duration);
        }
        if (MethodTraceEvent.shouldCommit(duration)) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
    }
}

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void traceObjectInit(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTraceEvent.shouldCommit(duration) && JVM.getEventWriter() != null) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
    }

    public static void timingObjectInit(long startTime, long methodId) {

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void traceTimingObjectInit(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTraceEvent.shouldCommit(duration) && JVM.getEventWriter() != null) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addObjectTiming(duration);
        }

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void trace(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTraceEvent.shouldCommit(duration)) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
    }

    public static void timing(long startTime, long methodId) {

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addTiming(methodId, duration);
        }
        if (MethodTraceEvent.shouldCommit(duration)) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
    }
}

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        jdk.internal.event.SerializationMisdeclarationEvent.class,
        jdk.internal.event.SocketReadEvent.class,
        jdk.internal.event.SocketWriteEvent.class,
        jdk.internal.event.ThreadSleepEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.VirtualThreadStartEvent.class,
        jdk.internal.event.VirtualThreadEndEvent.class,
        jdk.internal.event.VirtualThreadSubmitFailedEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,
        jdk.internal.event.FinalFieldMutationEvent.class,
        DirectBufferStatisticsEvent.class,
        InitialSecurityPropertyEvent.class,
        MethodTraceEvent.class,
        MethodTimingEvent.class,
    };

    private static final Runnable emitExceptionStatistics = JDKEvents::emitExceptionStatistics;
    private static final Runnable emitDirectBufferStatistics = JDKEvents::emitDirectBufferStatistics;
    private static final Runnable emitContainerConfiguration = JDKEvents::emitContainerConfiguration;
    private static final Runnable emitContainerCPUUsage = JDKEvents::emitContainerCPUUsage;
    private static final Runnable emitContainerCPUThrottling = JDKEvents::emitContainerCPUThrottling;
    private static final Runnable emitContainerMemoryUsage = JDKEvents::emitContainerMemoryUsage;
    private static final Runnable emitContainerIOUsage = JDKEvents::emitContainerIOUsage;
    private static final Runnable emitInitialSecurityProperties = JDKEvents::emitInitialSecurityProperties;

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        jdk.internal.event.SerializationMisdeclarationEvent.class,
        jdk.internal.event.SocketReadEvent.class,
        jdk.internal.event.SocketWriteEvent.class,
        jdk.internal.event.ThreadSleepEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.VirtualThreadStartEvent.class,
        jdk.internal.event.VirtualThreadEndEvent.class,
        jdk.internal.event.VirtualThreadSubmitFailedEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,
        jdk.internal.event.FinalFieldMutationEvent.class,
        DirectBufferStatisticsEvent.class,
        InitialSecurityPropertyEvent.class,
        MethodTraceEvent.class,
        MethodTimingEvent.class,
    };

    private static final Runnable emitExceptionStatistics = JDKEvents::emitExceptionStatistics;
    private static final Runnable emitDirectBufferStatistics = JDKEvents::emitDirectBufferStatistics;
    private static final Runnable emitContainerConfiguration = JDKEvents::emitContainerConfiguration;
    private static final Runnable emitContainerCPUUsage = JDKEvents::emitContainerCPUUsage;
    private static final Runnable emitContainerCPUThrottling = JDKEvents::emitContainerCPUThrottling;
    private static final Runnable emitContainerMemoryUsage = JDKEvents::emitContainerMemoryUsage;
    private static final Runnable emitContainerIOUsage = JDKEvents::emitContainerIOUsage;
    private static final Runnable emitInitialSecurityProperties = JDKEvents::emitInitialSecurityProperties;

src/jdk.jfr/share/classes/jdk/jfr/events/MethodTraceEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Contextual;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.StackTrace;

@Name("jdk.MethodTrace")
@Label("Method Trace")
@Category({ "Java Virtual Machine", "Method Tracing" })
@StackTrace(true)
public final class MethodTraceEvent extends AbstractJDKEvent {

    @Contextual
    @Label("Method")
    private long method;

    public static void commit(long start, long duration, long method) {
        // Generated by JFR
    }

    public static long timestamp() {
        // Generated by JFR
        return 0;

src/jdk.jfr/share/classes/jdk/jfr/events/MethodTraceEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Contextual;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.StackTrace;

@Name("jdk.MethodTrace")
@Label("Method Trace")
@Category({ "Java Virtual Machine", "Method Tracing" })
@StackTrace(true)
public final class MethodTraceEvent extends AbstractJDKEvent {

    @Contextual
    @Label("Method")
    private long method;

    public static void commit(long start, long duration, long method) {
        // Generated by JFR
    }

    public static long timestamp() {
        // Generated by JFR
        return 0;

Event configuration settings across JFR profiles
Configuration enabled filter stackTrace threshold
default true null true 0 ms
profiling true null true 0 ms

Event fields with their types and descriptions
Field Type Description
method Method Method

MethodTiming

default profiling startTime every chunk 25 27 28

Category: Java Application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void timingObjectInit(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addObjectTiming(duration);
        }
    }

    public static void traceTimingObjectInit(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTraceEvent.shouldCommit(duration) && JVM.getEventWriter() != null) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addObjectTiming(duration);
        }
    }

    public static void trace(long startTime, long methodId) {

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void timing(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addTiming(methodId, duration);
        }
    }

    public static void traceTiming(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addTiming(methodId, duration);
        }
        if (MethodTraceEvent.shouldCommit(duration)) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void timingObjectInit(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addObjectTiming(duration);
        }
    }

    public static void traceTimingObjectInit(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTraceEvent.shouldCommit(duration) && JVM.getEventWriter() != null) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addObjectTiming(duration);
        }
    }

    public static void trace(long startTime, long methodId) {

src/jdk.jfr/share/classes/jdk/jfr/tracing/MethodTracer.java:

    public static void timing(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addTiming(methodId, duration);
        }
    }

    public static void traceTiming(long startTime, long methodId) {
        long endTime = JVM.counterTime();
        long duration = endTime - startTime;
        if (MethodTimingEvent.enabled()) {
            PlatformTracer.addTiming(methodId, duration);
        }
        if (MethodTraceEvent.shouldCommit(duration)) {
            MethodTraceEvent.commit(startTime, duration, methodId);
        }

src/jdk.jfr/share/classes/jdk/jfr/internal/tracing/PlatformTracer.java:

        s.append(message);
        s.append(" for ");
        s.append(className.replace("/", "."));
        s.append(" in module ");
        s.append(module.getName());
        s.append(" and class loader " + module.getClassLoader());
        Logger.log(LogTag.JFR_METHODTRACE, level, s.toString());
    }

    public static void emitTiming() {
        // Metadata lock prevents rotation/flush while emitting events.
        synchronized (MetadataRepository.getInstance()) {
            removeClasses(JVM.drainStaleMethodTracerIds());
            long timestamp = MethodTimingEvent.timestamp();
            for (var tc : timedClasses.values()) {
                tc.emit(timestamp);
            }
        }
    }

    public static void addObjectTiming(long duration) {
        OBJECT.invocations().getAndIncrement();
        OBJECT.time().addAndGet(duration);
        OBJECT.updateMinMax(duration);
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/tracing/PlatformTracer.java:

        s.append(message);
        s.append(" for ");
        s.append(className.replace("/", "."));
        s.append(" in module ");
        s.append(module.getName());
        s.append(" and class loader " + module.getClassLoader());
        Logger.log(LogTag.JFR_METHODTRACE, level, s.toString());
    }

    public static void emitTiming() {
        // Metadata lock prevents rotation/flush while emitting events.
        synchronized (MetadataRepository.getInstance()) {
            removeClasses(JVM.drainStaleMethodTracerIds());
            long timestamp = MethodTimingEvent.timestamp();
            for (var tc : timedClasses.values()) {
                tc.emit(timestamp);
            }
        }
    }

    public static void addObjectTiming(long duration) {
        OBJECT.invocations().getAndIncrement();
        OBJECT.time().addAndGet(duration);
        OBJECT.updateMinMax(duration);
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/tracing/TimedClass.java:

    public void emit(long timestamp) {
        for (var tm : methods.values()) {
            if (tm.published().get()) {
                long methodId = tm.method().methodId();
                long invocations = tm.invocations().get();
                long time = tm.time().get();
                long min = tm.minimum().get();
                long max = tm.maximum().get();
                if (time == 0 || invocations == 0) {
                    // If time is zero, it's a low resolution clock and more invocations are needed.
                    MethodTimingEvent.commit(timestamp, methodId, invocations, MISSING, MISSING, MISSING);
                } else {
                    long average = (time + invocations / 2) / invocations;
                    if (min == Long.MAX_VALUE) {
                        min = average;
                    }
                    if (max == Long.MIN_VALUE) {
                        max = average;
                    }
                    min = Math.min(min, average);
                    max = Math.max(max, average);
                    MethodTimingEvent.commit(timestamp, methodId, invocations, min, average, max);
                }
                tm.method().log("Emitted event");
            }
        }
    }
}

src/jdk.jfr/share/classes/jdk/jfr/internal/tracing/TimedClass.java:

    public void emit(long timestamp) {
        for (var tm : methods.values()) {
            if (tm.published().get()) {
                long methodId = tm.method().methodId();
                long invocations = tm.invocations().get();
                long time = tm.time().get();
                long min = tm.minimum().get();
                long max = tm.maximum().get();
                if (time == 0 || invocations == 0) {
                    // If time is zero, it's a low resolution clock and more invocations are needed.
                    MethodTimingEvent.commit(timestamp, methodId, invocations, MISSING, MISSING, MISSING);
                } else {
                    long average = (time + invocations / 2) / invocations;
                    if (min == Long.MAX_VALUE) {
                        min = average;
                    }
                    if (max == Long.MIN_VALUE) {
                        max = average;
                    }
                    min = Math.min(min, average);
                    max = Math.max(max, average);
                    MethodTimingEvent.commit(timestamp, methodId, invocations, min, average, max);
                }
                tm.method().log("Emitted event");
            }
        }
    }
}

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        jdk.internal.event.VirtualThreadEndEvent.class,
        jdk.internal.event.VirtualThreadSubmitFailedEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,
        jdk.internal.event.FinalFieldMutationEvent.class,
        DirectBufferStatisticsEvent.class,
        InitialSecurityPropertyEvent.class,
        MethodTraceEvent.class,
        MethodTimingEvent.class,
    };

    private static final Runnable emitExceptionStatistics = JDKEvents::emitExceptionStatistics;
    private static final Runnable emitDirectBufferStatistics = JDKEvents::emitDirectBufferStatistics;
    private static final Runnable emitContainerConfiguration = JDKEvents::emitContainerConfiguration;
    private static final Runnable emitContainerCPUUsage = JDKEvents::emitContainerCPUUsage;
    private static final Runnable emitContainerCPUThrottling = JDKEvents::emitContainerCPUThrottling;

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        try {
            if (initializationTriggered == false) {
                for (Class<?> eventClass : eventClasses) {
                    MetadataRepository.getInstance().register((Class<? extends Event>) eventClass);
                }
                PeriodicEvents.addJavaEvent(jdk.internal.event.ExceptionStatisticsEvent.class, emitExceptionStatistics);
                PeriodicEvents.addJavaEvent(DirectBufferStatisticsEvent.class, emitDirectBufferStatistics);
                PeriodicEvents.addJavaEvent(InitialSecurityPropertyEvent.class, emitInitialSecurityProperties);
                PeriodicEvents.addJavaEvent(MethodTimingEvent.class, emitMethodTiming);

                initializeContainerEvents();
                JFRTracing.enable();
                initializationTriggered = true;
            }
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not initialize JDK events. " + e.getMessage());

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

            for (String key : p.stringPropertyNames()) {
                InitialSecurityPropertyEvent e = new InitialSecurityPropertyEvent();
                e.key = key;
                e.value = p.getProperty(key);
                e.commit();
            }
        }
    }

    private static void emitMethodTiming() {
        if (MethodSetting.isInitialized() && MethodTimingEvent.enabled()) {
            PlatformTracer.emitTiming();
        }
    }
}

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        jdk.internal.event.VirtualThreadEndEvent.class,
        jdk.internal.event.VirtualThreadSubmitFailedEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,
        jdk.internal.event.FinalFieldMutationEvent.class,
        DirectBufferStatisticsEvent.class,
        InitialSecurityPropertyEvent.class,
        MethodTraceEvent.class,
        MethodTimingEvent.class,
    };

    private static final Runnable emitExceptionStatistics = JDKEvents::emitExceptionStatistics;
    private static final Runnable emitDirectBufferStatistics = JDKEvents::emitDirectBufferStatistics;
    private static final Runnable emitContainerConfiguration = JDKEvents::emitContainerConfiguration;
    private static final Runnable emitContainerCPUUsage = JDKEvents::emitContainerCPUUsage;
    private static final Runnable emitContainerCPUThrottling = JDKEvents::emitContainerCPUThrottling;

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        try {
            if (initializationTriggered == false) {
                for (Class<?> eventClass : eventClasses) {
                    MetadataRepository.getInstance().register((Class<? extends Event>) eventClass);
                }
                PeriodicEvents.addJavaEvent(jdk.internal.event.ExceptionStatisticsEvent.class, emitExceptionStatistics);
                PeriodicEvents.addJavaEvent(DirectBufferStatisticsEvent.class, emitDirectBufferStatistics);
                PeriodicEvents.addJavaEvent(InitialSecurityPropertyEvent.class, emitInitialSecurityProperties);
                PeriodicEvents.addJavaEvent(MethodTimingEvent.class, emitMethodTiming);

                initializeContainerEvents();
                JFRTracing.enable();
                initializationTriggered = true;
            }
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not initialize JDK events. " + e.getMessage());

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

            for (String key : p.stringPropertyNames()) {
                InitialSecurityPropertyEvent e = new InitialSecurityPropertyEvent();
                e.key = key;
                e.value = p.getProperty(key);
                e.commit();
            }
        }
    }

    private static void emitMethodTiming() {
        if (MethodSetting.isInitialized() && MethodTimingEvent.enabled()) {
            PlatformTracer.emitTiming();
        }
    }
}

src/jdk.jfr/share/classes/jdk/jfr/events/MethodTimingEvent.java:

@Name("jdk.MethodTiming")
@Label("Method Timing")
@Category({ "Java Virtual Machine", "Method Tracing" })
@RemoveFields({ "duration", "eventThread", "stackTrace" })
@Description("Measures the approximate time it takes for a method to execute, including all delays, not just CPU processing time")
public final class MethodTimingEvent extends AbstractJDKEvent {

    @Label("Method")
    public long method;

    @Label("Invocations")
    public long invocations;

    @Label("Minimum Time")
    @Description("The value may be missing (Long.MIN_VALUE) if the clock-resolution is too low to establish a minimum time")
    @Timespan(Timespan.TICKS)
    public long minimum;

src/jdk.jfr/share/classes/jdk/jfr/events/MethodTimingEvent.java:

@Name("jdk.MethodTiming")
@Label("Method Timing")
@Category({ "Java Virtual Machine", "Method Tracing" })
@RemoveFields({ "duration", "eventThread", "stackTrace" })
@Description("Measures the approximate time it takes for a method to execute, including all delays, not just CPU processing time")
public final class MethodTimingEvent extends AbstractJDKEvent {

    @Label("Method")
    public long method;

    @Label("Invocations")
    public long invocations;

    @Label("Minimum Time")
    @Description("The value may be missing (Long.MIN_VALUE) if the clock-resolution is too low to establish a minimum time")
    @Timespan(Timespan.TICKS)
    public long minimum;

Event configuration settings across JFR profiles
Configuration enabled filter period
default true null endChunk
profiling true null endChunk

Event fields with their types and descriptions
Field Type Description
method Method Method
invocations long Invocations The number of times the method was invoked
minimum Tickspan Minimum An approximation of the minimum wall-clock time it took for the method to execute
average Tickspan Average An approximation of the average wall-clock time it took for the method to execute
maximum Tickspan Maximum An approximation of the maximum wall-clock time it took for the method to execute

SocketWrite

throttle default profiling startTime duration 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/SocketWriteEvent.java

Category: Java Application

Excludes in stack trace: java.io.OutputStream, java.net.Socket$SocketOutputStream, java.nio.channels.SocketChannel, sun.nio.ch.SocketOutputStream

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Writing data to a socket

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/SocketWriteEvent.java:

/**
 * A JFR event for socket write operations.  This event is mirrored in
 * {@code jdk.jfr.events.SocketWriteEvent } where the metadata for the event is
 * provided with annotations.  Some of the methods are replaced by generated
 * methods when jfr is enabled.  Note that the order of the arguments of the
 * {@link #commit(long, long, String, String, int, long)} method
 * must be the same as the order of the fields.
 */
public class SocketWriteEvent extends Event {

    // THE ORDER OF THE FOLLOWING FIELDS IS IMPORTANT!
    // The order must match the argument order of the generated commit method.
    public String host;
    public String address;
    public int port;
    public long bytesWritten;

    /**
     * Actually commit a socket write event.  This is generated automatically.
     * The order of the fields must be the same as the parameters in this method.

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
        register("jdk.internal.event.FinalFieldMutationEvent", FinalFieldMutationEvent.class);

src/jdk.jfr/share/classes/jdk/jfr/events/SocketWriteEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "SocketWrite")
@Label("Socket Write")
@Category("Java Application")
@Description("Writing data to a socket")
@StackFilter({"java.io.OutputStream",
              "java.net.Socket$SocketOutputStream",
              "java.nio.channels.SocketChannel",
              "sun.nio.ch.SocketOutputStream"})
@Throttle
public final class SocketWriteEvent extends MirrorEvent {

    @Label("Remote Host")
    public String host;

    @Label("Remote Address")
    public String address;

    @Label("Remote Port")
    public int port;

    @Label("Bytes Written")

src/java.base/share/classes/java/net/Socket.java:

        private final Socket parent;
        private final OutputStream out;
        SocketOutputStream(Socket parent, OutputStream out) {
            this.parent = parent;
            this.out = out;
        }
        @Override
        public void write(int b) throws IOException {
            byte[] a = new byte[] { (byte) b };
            write(a, 0, 1);
        }
        @Override
        public void write(byte[] b, int off, int len) throws IOException {
            if (!SocketWriteEvent.enabled()) {
                implWrite(b, off, len);
                return;
            }
            long start = SocketWriteEvent.timestamp();
            implWrite(b, off, len);
            SocketWriteEvent.offer(start, len, parent.getRemoteSocketAddress());
        }

        private void implWrite(byte[] b, int off, int len) throws IOException {
            try {
                out.write(b, off, len);
            } catch (InterruptedIOException e) {
                Thread thread = Thread.currentThread();
                if (thread.isVirtual() && thread.isInterrupted()) {
                    close();
                    throw new SocketException("Closed by interrupt");
                }

src/java.base/share/classes/sun/nio/ch/SocketChannelImpl.java:

        } finally {
            writeLock.unlock();
        }
    }

    @Override
    public int write(ByteBuffer buf) throws IOException {
        if (!SocketWriteEvent.enabled()) {
            return implWrite(buf);
        }
        long start = SocketWriteEvent.timestamp();
        int nbytes = implWrite(buf);
        SocketWriteEvent.offer(start, nbytes, remoteAddress());
        return nbytes;
    }

    @Override
    public long write(ByteBuffer[] srcs, int offset, int length)
        throws IOException
    {
        if (!SocketWriteEvent.enabled()) {
            return implWrite(srcs, offset, length);
        }
        long start = SocketWriteEvent.timestamp();
        long nbytes = implWrite(srcs, offset, length);
        SocketWriteEvent.offer(start, nbytes, remoteAddress());
        return nbytes;
    }

    /**
     * Writes a byte of out of band data.

src/java.base/share/classes/sun/nio/ch/SocketOutputStream.java:

     */
    SocketChannelImpl channel() {
        return sc;
    }

    @Override
    public void write(int b) throws IOException {
        byte[] a = new byte[]{(byte) b};
        write(a, 0, 1);
    }

    @Override
    public void write(byte[] b, int off, int len) throws IOException {
        if (!SocketWriteEvent.enabled()) {
            sc.blockingWriteFully(b, off, len);
            return;
        }
        long start = SocketWriteEvent.timestamp();
        sc.blockingWriteFully(b, off, len);
        SocketWriteEvent.offer(start, len, sc.remoteAddress());
    }

    @Override
    public void close() throws IOException {
        sc.close();
    }
}

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold throttle
default true true 1 ms 100/s 25+
profiling true true 1 ms 300/s 25+

Event fields with their types and descriptions
Field Type Description
host string Remote Host
address string Remote Address
port int Remote Port
bytesWritten long: bytes Bytes Written Number of bytes written to the socket

Examples 3
Example event data values and properties
address string
127.0.0.1
bytesWritten long: bytes
64
host string
127.0.0.1
port int
58232
startTime long: millis
2397524357
Example event data values and properties
address string
127.0.0.1
bytesWritten long: bytes
64
host string
127.0.0.1
port int
40235
startTime long: millis
3771518502
Example event data values and properties
address string
127.0.0.1
bytesWritten long: bytes
64
host string
127.0.0.1
port int
36229
startTime long: millis
2266678847

JavaErrorThrow

default profiling startTime duration 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/ErrorThrownEvent.java

Category: Java Application

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

An object derived from java.lang.Error has been created. OutOfMemoryErrors are ignored

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default true true
profiling true true

Event fields with their types and descriptions
Field Type Description
message string Message
thrownClass Class Class

Examples 3
Example event data values and properties
message string
Native Library /opt/hostedtoolcache/Java_SapMachine_jdk/25.0.4-1/x64/lib/libnet.so already loaded in another classloader
startTime long: millis
1331108367
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/UnsatisfiedLinkError
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
Example event data values and properties
message string
'java.lang.Object java.lang.invoke.DirectMethodHandle$Holder.newInvokeSpecial(java.lang.Object, long, java.lang.Object, java.lang.Object, java.lang.Object)'
startTime long: millis
492358865602
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/NoSuchMethodError
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
Example event data values and properties
message string
'java.lang.Object java.lang.invoke.DirectMethodHandle$Holder.invokeSpecialIFC(java.lang.Object, java.lang.Object, java.lang.Object, java.lang.Object, int, java.lang.Object, java.lang.Object)'
startTime long: millis
487461759357
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/NoSuchMethodError
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang

JavaExceptionThrow

throttle default profiling startTime duration 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/ExceptionThrownEvent.java

Category: Java Application

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

An object derived from java.lang.Exception has been created

Event configuration settings across JFR profiles
Configuration enabled stackTrace throttle
default true true 100/s 25+
profiling true true 300/s 25+

Event fields with their types and descriptions
Field Type Description
message string Message
thrownClass Class Class

Examples 3
Example event data values and properties
message string
'void java.lang.invoke.DirectMethodHandle$Holder.invokeInterface(java.lang.Object, java.lang.Object, java.lang.Object, java.lang.Object)'
startTime long: millis
1309726190
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/NoSuchMethodError
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
Example event data values and properties
message string
null
startTime long: millis
453485439601
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Exception
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
Example event data values and properties
message string
null
startTime long: millis
448558068721
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Exception
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang

VirtualThreadStart

startTime duration 19 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/VirtualThreadStartEvent.java

Category: Java Application

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/VirtualThreadStartEvent.java:

package jdk.internal.event;

/**
 * Event recording that a virtual thread has been started.
 */
public class VirtualThreadStartEvent extends Event {
    private static final VirtualThreadStartEvent EVENT = new VirtualThreadStartEvent();

    /**
     * Returns {@code true} if event is enabled, {@code false} otherwise.
     */
    public static boolean isTurnedOn() {
        return EVENT.isEnabled();
    }

    public long javaThreadId;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
        register("jdk.internal.event.FinalFieldMutationEvent", FinalFieldMutationEvent.class);
    };

    private static void register(String eventClassName, Class<? extends MirrorEvent> mirrorClass) {

src/jdk.jfr/share/classes/jdk/jfr/events/VirtualThreadStartEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.MirrorEvent;
import jdk.jfr.internal.RemoveFields;

@Category("Java Application")
@Label("Virtual Thread Start")
@Name("jdk.VirtualThreadStart")
@RemoveFields("duration")
public final class VirtualThreadStartEvent extends MirrorEvent {

    @Label("Thread Id")
    public long javaThreadId;

}

src/java.base/share/classes/java/lang/VirtualThread.java:

            event.javaThreadId = threadId();
            event.exceptionMessage = ree.getMessage();
            event.commit();
        }
    }

    /**
     * Runs a task in the context of this virtual thread.
     */
    private void run(Runnable task) {
        assert Thread.currentThread() == this && state == RUNNING;

        // emit JFR event if enabled
        if (VirtualThreadStartEvent.isTurnedOn()) {
            var event = new VirtualThreadStartEvent();
            event.javaThreadId = threadId();
            event.commit();
        }

        Object bindings = Thread.scopedValueBindings();
        try {
            runWith(bindings, task);
        } catch (Throwable exc) {
            dispatchUncaughtException(exc);
        } finally {
            // pop any remaining scopes from the stack, this may block

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default false true
profiling false true

Event fields with their types and descriptions
Field Type Description
javaThreadId long Thread Id

Examples 3
Example event data values and properties
javaThreadId long
38
startTime long: millis
533294392
Example event data values and properties
javaThreadId long
46
startTime long: millis
440665184
Example event data values and properties
javaThreadId long
44
startTime long: millis
583498751

ThreadSleep

default profiling startTime duration 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/ThreadSleepEvent.java

Category: Java Application

Excludes in stack trace: java.lang.Thread::afterSleep, java.lang.Thread::sleepNanos, java.lang.Thread::sleep

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/ThreadSleepEvent.java:

package jdk.internal.event;

/**
 * Event recording thread sleeping.
 */

public final class ThreadSleepEvent extends Event {
    public long time;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
        register("jdk.internal.event.FinalFieldMutationEvent", FinalFieldMutationEvent.class);
    };

src/jdk.jfr/share/classes/jdk/jfr/events/ThreadSleepEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.Timespan;
import jdk.jfr.internal.MirrorEvent;

@Category("Java Application")
@Label("Java Thread Sleep")
@Name("jdk.ThreadSleep")
@StackFilter({"java.lang.Thread::afterSleep",
              "java.lang.Thread::sleepNanos",
              "java.lang.Thread::sleep"})
public final class ThreadSleepEvent extends MirrorEvent {
    @Label("Sleep Time")
    @Timespan(Timespan.NANOSECONDS)
    public long time;
}

src/java.base/share/classes/java/lang/Thread.java:

    public static void yield() {
        if (currentThread() instanceof VirtualThread vthread) {
            vthread.tryYield();
        } else {
            yield0();
        }
    }

    private static native void yield0();

    /**
     * Called before sleeping to create a jdk.ThreadSleep event.
     */
    private static ThreadSleepEvent beforeSleep(long nanos) {
        try {
            ThreadSleepEvent event = new ThreadSleepEvent();
            if (event.isEnabled()) {
                event.time = nanos;
                event.begin();
                return event;
            }
        } catch (OutOfMemoryError e) {
            // ignore
        }
        return null;
    }


    /**
     * Called after sleeping to commit the jdk.ThreadSleep event.
     */
    private static void afterSleep(ThreadSleepEvent event) {
        if (event != null) {
            try {
                event.commit();
            } catch (OutOfMemoryError e) {
                // ignore
            }
        }
    }

    /**
     * Sleep for the specified number of nanoseconds, subject to the precision
     * and accuracy of system timers and schedulers.
     */
    private static void sleepNanos(long nanos) throws InterruptedException {
        ThreadSleepEvent event = beforeSleep(nanos);
        try {
            if (currentThread() instanceof VirtualThread vthread) {
                vthread.sleepNanos(nanos);
            } else {
                sleepNanos0(nanos);
            }
        } finally {
            afterSleep(event);
        }
    }

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 20 ms
profiling true true 10 ms

Event fields with their types and descriptions
Field Type Description
time long: nanos Sleep Time

Examples 3
Example event data values and properties
startTime long: millis
671474056
time long: nanos
5000000
Example event data values and properties
startTime long: millis
453442673693
time long: nanos
10000000
Example event data values and properties
startTime long: millis
447479613930
time long: nanos
200000000

FileRead

throttle default profiling startTime duration 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/FileReadEvent.java

Category: Java Application

Excludes in stack trace: java.nio.channels.FileChannel, java.io.DataInputStream, java.io.FileInputStream, java.io.InputStream, java.io.RandomAccessFile, sun.nio.ch.ChannelInputStream, sun.nio.ch.FileChannelImpl

Reading data from a file

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/FileReadEvent.java:

package jdk.internal.event;

/**
 * Event recording file reads.
 */
public final class FileReadEvent extends Event {

    // The order of these fields must be the same as the parameters in
    // commit(..., String, long, boolean)
    public String path;
    public long bytesRead;
    public boolean endOfFile;

    public static boolean enabled() {
        // Generated by JFR
        return false;
    }

    public static long timestamp() {
        // Generated by JFR
        return 0L;
    }

    public static boolean shouldThrottleCommit(long duration, long end) {
        // Generated by JFR

src/java.base/share/classes/java/io/FileInputStream.java:

     * @return     the next byte of data, or {@code -1} if the end of the
     *             file is reached.
     * @throws     IOException {@inheritDoc}
     */
    @Override
    public int read() throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceRead0();
        }
        return read0();
    }

src/java.base/share/classes/java/io/FileInputStream.java:

    private native int read0() throws IOException;

    private int traceRead0() throws IOException {
        int result = 0;
        long bytesRead = 0;
        long start = FileReadEvent.timestamp();
        try {
            result = read0();
            if (result < 0) {
                bytesRead = -1;
            } else {
                bytesRead = 1;
            }
        } finally {
            FileReadEvent.offer(start, path, bytesRead);
        }
        return result;
    }

src/java.base/share/classes/java/io/FileInputStream.java:

     * @throws    IOException If an I/O error has occurred.
     */
    private native int readBytes(byte[] b, int off, int len) throws IOException;

    private int traceReadBytes(byte b[], int off, int len) throws IOException {
        int bytesRead = 0;
        long start = FileReadEvent.timestamp();
        try {
            bytesRead = readBytes(b, off, len);
        } finally {
            FileReadEvent.offer(start, path, bytesRead);
        }
        return bytesRead;
    }

src/java.base/share/classes/java/io/FileInputStream.java:

     *             {@code -1} if there is no more data because the end of
     *             the file has been reached.
     * @throws     IOException  if an I/O error occurs.
     */
    @Override
    public int read(byte[] b) throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceReadBytes(b, 0, b.length);
        }
        return readBytes(b, 0, b.length);
    }

src/java.base/share/classes/java/io/FileInputStream.java:

     * @throws     NullPointerException {@inheritDoc}
     * @throws     IndexOutOfBoundsException {@inheritDoc}
     * @throws     IOException  if an I/O error occurs.
     */
    @Override
    public int read(byte[] b, int off, int len) throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceReadBytes(b, off, len);
        }
        return readBytes(b, off, len);
    }

src/java.base/share/classes/java/io/RandomAccessFile.java:

     *             file has been reached.
     * @throws     IOException  if an I/O error occurs. Not thrown if
     *                          end-of-file has been reached.
     */
    public int read() throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceRead0();
        }
        return read0();

src/java.base/share/classes/java/io/RandomAccessFile.java:

    private native int read0() throws IOException;

    private int traceRead0() throws IOException {
        int result = 0;
        long bytesRead = 0;
        long start = FileReadEvent.timestamp();
        try {
            result = read0();
            if (result < 0) {

src/java.base/share/classes/java/io/RandomAccessFile.java:

                bytesRead = -1;
            } else {
                bytesRead = 1;
            }
        } finally {
            FileReadEvent.offer(start, path, bytesRead);
        }
        return result;
    }

src/java.base/share/classes/java/io/RandomAccessFile.java:

     * @param     off the start offset of the data.
     * @param     len the number of bytes to read.
     * @throws    IOException If an I/O error has occurred.
     */
    private int readBytes(byte[] b, int off, int len) throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceReadBytes0(b, off, len);
        }
        return readBytes0(b, off, len);

src/java.base/share/classes/java/io/RandomAccessFile.java:

    private native int readBytes0(byte[] b, int off, int len) throws IOException;

    private int traceReadBytes0(byte b[], int off, int len) throws IOException {
        int bytesRead = 0;
        long start = FileReadEvent.timestamp();
        try {
            bytesRead = readBytes0(b, off, len);
        } finally {
            FileReadEvent.offer(start, path, bytesRead);
        }
        return bytesRead;
    }

src/java.base/share/classes/java/io/RandomAccessFile.java:

     *             of file is encountered before even one byte is read.
     * @throws     IOException  if an I/O error occurs.
     */

    public final String readLine() throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            long bytesRead = 0;
            long start = FileReadEvent.timestamp();
            try {
                String result = implReadLine();
                bytesRead = result == null ? 0 : result.length();
                return result;
            } finally {
                FileReadEvent.offer(start, path, bytesRead);
            }
        }
        return implReadLine();

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

/**
 * This class registers all mirror events.
 */
final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);

src/jdk.jfr/share/classes/jdk/jfr/events/FileReadEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "FileRead")
@Label("File Read")
@Category("Java Application")
@Description("Reading data from a file")
@StackFilter({"java.nio.channels.FileChannel",
              "java.io.DataInputStream",
              "java.io.FileInputStream",
              "java.io.InputStream",
              "java.io.RandomAccessFile",
              "sun.nio.ch.ChannelInputStream",
              "sun.nio.ch.FileChannelImpl"})
@Throttle
public final class FileReadEvent extends MirrorEvent {

    @Label("Path")
    @Description("Full path of the file, or N/A if a file descriptor was used to create the stream, for example System.in")
    public String path;

    @Label("Bytes Read")
    @Description("Number of bytes read from the file (possibly 0)")
    @DataAmount
    public long bytesRead;

    @Label("End of File")

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

    @Override
    public int read(ByteBuffer dst) throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceImplRead(dst);
        }
        return implRead(dst);

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

    private int traceImplRead(ByteBuffer dst) throws IOException {
        int bytesRead = 0;
        long start = FileReadEvent.timestamp();
        try {
            bytesRead = implRead(dst);
        } finally {
            FileReadEvent.offer(start, path, bytesRead);
        }
        return bytesRead;
    }

    @Override
    public long read(ByteBuffer[] dsts, int offset, int length) throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceImplRead(dsts, offset, length);
        }
        return implRead(dsts, offset, length);

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

    private long traceImplRead(ByteBuffer[] dsts, int offset, int length) throws IOException {
        long bytesRead = 0;
        long start = FileReadEvent.timestamp();
        try {
            bytesRead = implRead(dsts, offset, length);
        } finally {
            FileReadEvent.offer(start, path, bytesRead);
        }
        return bytesRead;
    }

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

    @Override
    public int read(ByteBuffer dst, long position) throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceImplRead(dst, position);
        }
        return implRead(dst, position);

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

    private int traceImplRead(ByteBuffer dst, long position) throws IOException {
        int bytesRead = 0;
        long start = FileReadEvent.timestamp();
        try {
            bytesRead = implRead(dst, position);
        } finally {
            FileReadEvent.offer(start, path, bytesRead);
        }
        return bytesRead;
    }

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

    @Override
    public int write(ByteBuffer src, long position) throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceImplWrite(src, position);
        }
        return implWrite(src, position);

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold throttle
default true true 1 ms 100/s 25+
profiling true true 1 ms 300/s 25+

Event fields with their types and descriptions
Field Type Description
path string Path Full path of the file, or N/A if a file descriptor was used to create the stream, for example System.in
bytesRead long: bytes Bytes Read Number of bytes read from the file (possibly 0)
endOfFile boolean End of File If end of file was reached

Examples 3
Example event data values and properties
bytesRead long: bytes
4
endOfFile boolean
false
path string
/tmp/jfr_agent15005275580992799933.jar
startTime long: millis
642747880
Example event data values and properties
bytesRead long: bytes
8192
endOfFile boolean
false
path string
/tmp/jar_cache12334624613536327917.tmp
startTime long: millis
448119886250
Example event data values and properties
bytesRead long: bytes
8192
endOfFile boolean
false
path string
/tmp/jar_cache3220599901691524981.tmp
startTime long: millis
454314836371

FileForce

default profiling startTime duration 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/FileForceEvent.java

Category: Java Application

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Force updates to be written to file

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/FileForceEvent.java:

package jdk.internal.event;

/**
 * A JFR event for forced updates written to files.  This event is mirrored in
 * {@code jdk.jfr.events.FileForceEvent } where the event annotations are
 * provided.  Some of the methods are replaced by generated
 * methods when jfr is enabled.  Note that the order of the arguments of the
 * {@link #commit(long, long, String, boolean)} method
 * must be the same as the order of the fields.
 */
public class FileForceEvent extends Event {

    // THE ORDER OF THE FOLLOWING FIELDS IS IMPORTANT!
    // The order must match the argument order of the generated commit method.
    public String path;
    public boolean metaData;

    /**
     * Helper method to offer the data needed to potentially commit an event.
     * The duration of the operation is computed using the current
     * timestamp and the given start time.  If the duration is meets
     * or exceeds the configured value (determined by calling the generated method
     * {@link #shouldCommit(long)}), an event will be emitted by calling
     * {@link #commit(long, long, String, boolean)}.

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

/**
 * This class registers all mirror events.
 */
final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);

src/jdk.jfr/share/classes/jdk/jfr/events/FileForceEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.MirrorEvent;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "FileForce")
@Label("File Force")
@Category("Java Application")
@Description("Force updates to be written to file")
public final class FileForceEvent extends MirrorEvent {

    // The order of these fields must be the same as the parameters in
    // commit(..., String, boolean)

    @Label("Path")
    @Description("Full path of the file")
    public String path;

    @Label("Update Metadata")
    @Description("Whether the file metadata is updated")
    public boolean metaData;

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

                } finally {
                    Blocker.end(attempted);
                }
            } while ((rv == IOStatus.INTERRUPTED) && isOpen());
        } finally {
            threads.remove(ti);
            endBlocking(rv > -1);
            assert IOStatus.check(rv);
        }
    }

    @Override
    public void force(boolean metaData) throws IOException {
        if (!FileForceEvent.enabled()) {
            implForce(metaData);
            return;
        }
        long start = FileForceEvent.timestamp();
        implForce(metaData);
        FileForceEvent.offer(start, path, metaData);
    }

    // Assume at first that the underlying kernel supports sendfile/equivalent;
    // set this to true if we find out later that it doesn't
    //
    private static volatile boolean transferToDirectNotSupported;

    // Assume at first that the underlying kernel supports copy_file_range/equivalent;
    // set this to true if we find out later that it doesn't
    //
    private static volatile boolean transferFromDirectNotSupported;

src/java.base/share/classes/sun/nio/ch/SimpleAsynchronousFileChannelImpl.java:

                do {
                    n = nd.force(fdObj, metaData);
                } while ((n == IOStatus.INTERRUPTED) && isOpen());
            } finally {
                end(n >= 0);
            }
        } finally {
            threads.remove(ti);
        }
    }

    @Override
    public void force(boolean metaData) throws IOException {
        if (!FileForceEvent.enabled()) {
            implForce(metaData);
            return;
        }
        long start = FileForceEvent.timestamp();
        implForce(metaData);
        FileForceEvent.offer(start, path, metaData);
    }

    @Override
    <A> Future<FileLock> implLock(final long position,
                                  final long size,
                                  final boolean shared,
                                  final A attachment,
                                  final CompletionHandler<FileLock,? super A> handler)
    {
        if (shared && !reading)
            throw new NonReadableChannelException();

src/java.base/windows/classes/sun/nio/ch/WindowsAsynchronousFileChannelImpl.java:

    private void implForce(boolean metaData) throws IOException {
        try {
            begin();
            nd.force(fdObj, metaData);
        } finally {
            end();
        }
    }

    @Override
    public void force(boolean metaData) throws IOException {
        if (!FileForceEvent.enabled()) {
            implForce(metaData);
            return;
        }
        long start = FileForceEvent.timestamp();
        implForce(metaData);
        FileForceEvent.offer(start, path, metaData);
    }

    // -- file locking --

    /**
     * Task that initiates locking operation and handles completion result.
     */
    private class LockTask<A> implements Runnable, Iocp.ResultHandler {
        private final long position;
        private final FileLockImpl fli;
        private final PendingFuture<FileLock,A> result;

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 20 ms
profiling true true 10 ms

Event fields with their types and descriptions
Field Type Description
path string Path Full path of the file
metaData boolean Update Metadata Whether the file metadata is updated

Examples 3
Example event data values and properties
metaData boolean
true
path string
/tmp/jfr_sample4646412869330140946.tmp
startTime long: millis
5108178301
Example event data values and properties
metaData boolean
true
path string
/tmp/jfr_sample7950200855328356358.tmp
startTime long: millis
1418481245
Example event data values and properties
metaData boolean
true
path string
/tmp/jfr_sample13137898057837233450.tmp
startTime long: millis
5014905945

FinalFieldMutation

default profiling startTime duration 26 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/FinalFieldMutationEvent.java

Category: Java Application

Excludes in stack trace: java.lang.reflect.Field, java.lang.reflect.ReflectAccess, java.lang.invoke.MethodHandles$Lookup

The event only represents a sample.There might be more mutations of the same final field, possibly with different stack traces.

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/FinalFieldMutationEvent.java:

package jdk.internal.event;

import java.lang.reflect.Field;

public class FinalFieldMutationEvent extends Event {

    public Class<?> declaringClass;
    public String fieldName;

    /**
     * We throttle FinalFieldMutation JFR events by generating only one event per field
     * during each JFR epoch.
     *
     * An event is emitted if enabled, the epoch encoded in the root instance differs
     * from the current epoch, and a thread exclusively updates to the current epoch.
     */
    public static void offer(Field root) {
        if (enabled() && tryUpdateEpoch(root)) {
            var event = new FinalFieldMutationEvent();
            event.declaringClass = root.getDeclaringClass();
            event.fieldName = root.getName();
            event.commit();
        }
    }

    private static boolean tryUpdateEpoch(Field root) {
        // Generated by JFR
        return false;
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
        register("jdk.internal.event.FinalFieldMutationEvent", FinalFieldMutationEvent.class);
    };

    private static void register(String eventClassName, Class<? extends MirrorEvent> mirrorClass) {
        mirrorLookup.put(eventClassName, mirrorClass);
    }

    static Class<? extends MirrorEvent> find(Class<? extends jdk.internal.event.Event> eventClass) {
        return find(Utils.isJDKClass(eventClass), eventClass.getName());
    }

    static Class<? extends MirrorEvent> find(boolean bootClassLoader, String name) {

src/jdk.jfr/share/classes/jdk/jfr/events/FinalFieldMutationEvent.java:

@Category("Java Application")
@Label("Final Field Mutation Sample")
@Description("The event only represents a sample." +
        "There might be more mutations of the same final field, possibly with different stack traces.")
@Name(Type.EVENT_NAME_PREFIX + "FinalFieldMutation")
@RemoveFields("duration")
@StackFilter({
        "java.lang.reflect.Field",
        "java.lang.reflect.ReflectAccess",
        "java.lang.invoke.MethodHandles$Lookup"
})
public final class FinalFieldMutationEvent extends MirrorEvent {

    @Label("Declaring Class")
    @Description("Declaring class with final field")
    public Class<?> declaringClass;

    @Label("Field Name")
    @Description("Field name of final field")
    public String fieldName;

}

src/java.base/share/classes/java/lang/reflect/Field.java:

                        WARNING: Mutating final fields will be blocked in a future release unless final field mutation is enabled
                        """, warningMsg, targetModule);
            }
        } else if (mode == ModuleBootstrap.IllegalFinalFieldMutation.DEBUG) {
            // print warning and stack trace
            var sb = new StringBuilder(finalFieldMutationWarning(caller, unreflect));
            StackWalker.getInstance(StackWalker.Option.RETAIN_CLASS_REFERENCE)
                    .forEach(sf -> {
                        sb.append(System.lineSeparator()).append("\tat " + sf);
                    });
            VM.initialErr().println(sb);
        }

        FinalFieldMutationEvent.offer(root);
    }

    /**
     * Returns true if this final field is "deeply accessible" to the caller.
     * The field is deeply accessible if declaring class is in a package that is open
     * to the caller's module, or the field is public in a public class that is exported
     * to the caller's module.
     *
     * Updates to the module of the declaring class at runtime with {@code Module.addExports}
     * or {@code Module.addOpens} have no impact on the result of this method.
     */

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default true true
profiling true true

Event fields with their types and descriptions
Field Type Description
declaringClass Class Declaring Class Declaring class with final field
fieldName string Field Name Field name of final field

FileWrite

throttle default profiling startTime duration 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/FileWriteEvent.java

Category: Java Application

Excludes in stack trace: java.nio.channels.FileChannel, java.io.DataOutputStream, java.io.FileOutputStream, java.io.OutputStream, java.io.RandomAccessFile, sun.nio.ch.ChannelOutputStream, sun.nio.ch.FileChannelImpl

Writing data to a file

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/FileWriteEvent.java:

package jdk.internal.event;

/**
 * Event recording file writes.
 */
public final class FileWriteEvent extends Event {

    // The order of these fields must be the same as the parameters in
    // commit(..., String, long)
    public String path;
    public long bytesWritten;

    public static boolean enabled() {
        // Generated by JFR
        return false;
    }

    public static long timestamp() {
        // Generated by JFR
        return 0L;
    }

    public static boolean shouldThrottleCommit(long duration, long end) {
        // Generated by JFR
        return false;

src/java.base/share/classes/java/io/RandomAccessFile.java:

     * Writes the specified byte to this file. The write starts at
     * the current file pointer.
     *
     * @param      b   the {@code byte} to be written.
     * @throws     IOException  if an I/O error occurs.
     */
    public void write(int b) throws IOException {
        if (jfrTracing && FileWriteEvent.enabled()) {
            traceImplWrite(b);
            return;
        }
        implWrite(b);
    }

src/java.base/share/classes/java/io/RandomAccessFile.java:

        } finally {
            Blocker.end(attempted);
        }
    }

    private void traceImplWrite(int b) throws IOException {
        long bytesWritten = 0;
        long start = FileWriteEvent.timestamp();
        try {
            implWrite(b);
            bytesWritten = 1;
        } finally {
            FileWriteEvent.offer(start, path, bytesWritten);
        }
    }

    private native void write0(int b) throws IOException;

src/java.base/share/classes/java/io/RandomAccessFile.java:

     *
     * @param     b the data to be written
     * @param     off the start offset in the data
     * @param     len the number of bytes that are written
     * @throws    IOException If an I/O error has occurred.
     */
    private void writeBytes(byte[] b, int off, int len) throws IOException {
        if (jfrTracing && FileWriteEvent.enabled()) {
            traceImplWriteBytes(b, off, len);
            return;
        }
        implWriteBytes(b, off, len);
    }

src/java.base/share/classes/java/io/RandomAccessFile.java:

        } finally {
            Blocker.end(attempted);
        }
    }

    private void traceImplWriteBytes(byte b[], int off, int len) throws IOException {
        long bytesWritten = 0;
        long start = FileWriteEvent.timestamp();
        try {
            implWriteBytes(b, off, len);
            bytesWritten = len;
        } finally {
            FileWriteEvent.offer(start, path, bytesWritten);
        }
    }

    private native void writeBytes0(byte[] b, int off, int len) throws IOException;

src/java.base/share/classes/java/io/FileOutputStream.java:

     *     advances the position to the end of file
     */
    private native void write(int b, boolean append) throws IOException;

    private void traceWrite(int b, boolean append) throws IOException {
        long bytesWritten = 0;
        long start = FileWriteEvent.timestamp();
        try {
            write(b, append);
            bytesWritten = 1;
        } finally {
            FileWriteEvent.offer(start, path, bytesWritten);
        }
    }

    /**

src/java.base/share/classes/java/io/FileOutputStream.java:

     * @param      b   the byte to be written.
     * @throws     IOException  if an I/O error occurs.
     */
    @Override
    public void write(int b) throws IOException {
        boolean append = FD_ACCESS.getAppend(fd);
        if (jfrTracing && FileWriteEvent.enabled()) {
            traceWrite(b, append);
            return;
        }
        write(b, append);

src/java.base/share/classes/java/io/FileOutputStream.java:

     */
    private native void writeBytes(byte[] b, int off, int len, boolean append)
        throws IOException;

    private void traceWriteBytes(byte b[], int off, int len, boolean append) throws IOException {
        long bytesWritten = 0;
        long start = FileWriteEvent.timestamp();
        try {
            writeBytes(b, off, len, append);
            bytesWritten = len;
        } finally {
            FileWriteEvent.offer(start, path, bytesWritten);
        }
    }

    /**

src/java.base/share/classes/java/io/FileOutputStream.java:

     * @param      b   {@inheritDoc}
     * @throws     IOException  {@inheritDoc}
     */
    @Override
    public void write(byte[] b) throws IOException {
        boolean append = FD_ACCESS.getAppend(fd);
        if (jfrTracing && FileWriteEvent.enabled()) {
            traceWriteBytes(b, 0, b.length, append);
            return;
        }
        writeBytes(b, 0, b.length, append);

src/java.base/share/classes/java/io/FileOutputStream.java:

     * @throws     IOException  if an I/O error occurs.
     * @throws     IndexOutOfBoundsException {@inheritDoc}
     */
    @Override
    public void write(byte[] b, int off, int len) throws IOException {
        boolean append = FD_ACCESS.getAppend(fd);
        if (jfrTracing && FileWriteEvent.enabled()) {
            traceWriteBytes(b, off, len, append);
            return;
        }
        writeBytes(b, off, len, append);

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

/**
 * This class registers all mirror events.
 */
final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);

src/jdk.jfr/share/classes/jdk/jfr/events/FileWriteEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "FileWrite")
@Label("File Write")
@Category("Java Application")
@Description("Writing data to a file")
@StackFilter({"java.nio.channels.FileChannel",
              "java.io.DataOutputStream",
              "java.io.FileOutputStream",
              "java.io.OutputStream",
              "java.io.RandomAccessFile",
              "sun.nio.ch.ChannelOutputStream",
              "sun.nio.ch.FileChannelImpl"})
@Throttle
public final class FileWriteEvent extends MirrorEvent {

    @Label("Path")
    @Description("Full path of the file, or N/A if a file descriptor was used to create the stream, for example System.out and System.err")
    public String path;

    @Label("Bytes Written")
    @Description("Number of bytes written to the file")
    @DataAmount
    public long bytesWritten;
}

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

    @Override
    public int write(ByteBuffer src) throws IOException {
        if (jfrTracing && FileWriteEvent.enabled()) {
            return traceImplWrite(src);
        }
        return implWrite(src);
    }

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

    private int traceImplWrite(ByteBuffer src) throws IOException {
        int bytesWritten = 0;
        long start = FileWriteEvent.timestamp();
        try {
            bytesWritten = implWrite(src);
        } finally {
            FileWriteEvent.offer(start, path, bytesWritten);
        }
        return bytesWritten;
    }

    @Override
    public long write(ByteBuffer[] srcs, int offset, int length) throws IOException {
        if (jfrTracing && FileWriteEvent.enabled()) {
            return traceImplWrite(srcs, offset, length);
        }
        return implWrite(srcs, offset, length);
    }

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

    private long traceImplWrite(ByteBuffer[] srcs, int offset, int length) throws IOException {
        long bytesWritten = 0;
        long start = FileWriteEvent.timestamp();
        try {
            bytesWritten = implWrite(srcs, offset, length);
        } finally {
            FileWriteEvent.offer(start, path, bytesWritten);
        }
        return bytesWritten;
    }

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

    private int traceImplWrite(ByteBuffer src, long position) throws IOException {
        int bytesWritten = 0;
        long start = FileWriteEvent.timestamp();
        try {
            bytesWritten = implWrite(src, position);
        } finally {
            FileWriteEvent.offer(start, path, bytesWritten);
        }
        return bytesWritten;
    }

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold throttle
default true true 1 ms 100/s 25+
profiling true true 1 ms 300/s 25+

Event fields with their types and descriptions
Field Type Description
path string Path Full path of the file, or N/A if a file descriptor was used to create the stream, for example System.out and System.err
bytesWritten long: bytes Bytes Written Number of bytes written to the file

Examples 3
Example event data values and properties
bytesWritten long: bytes
1
path string
null
startTime long: millis
1330755315
Example event data values and properties
bytesWritten long: bytes
8192
path string
/tmp/jar_cache13473187686794800317.tmp
startTime long: millis
481015371557
Example event data values and properties
bytesWritten long: bytes
8270
path string
/tmp/jar_cache858886477500664727.tmp
startTime long: millis
484996245582

VirtualThreadEnd

startTime duration 19 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/VirtualThreadEndEvent.java

Category: Java Application

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/VirtualThreadEndEvent.java:

package jdk.internal.event;

/**
 * Event recording that a virtual thread has terminated.
 */
public class VirtualThreadEndEvent extends Event {
    private static final VirtualThreadEndEvent EVENT = new VirtualThreadEndEvent();

    /**
     * Returns {@code true} if event is enabled, {@code false} otherwise.
     */
    public static boolean isTurnedOn() {
        return EVENT.isEnabled();
    }

    public long javaThreadId;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
        register("jdk.internal.event.FinalFieldMutationEvent", FinalFieldMutationEvent.class);
    };

    private static void register(String eventClassName, Class<? extends MirrorEvent> mirrorClass) {
        mirrorLookup.put(eventClassName, mirrorClass);

src/jdk.jfr/share/classes/jdk/jfr/events/VirtualThreadEndEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.MirrorEvent;
import jdk.jfr.internal.RemoveFields;

@Category("Java Application")
@Label("Virtual Thread End")
@Name("jdk.VirtualThreadEnd")
@RemoveFields({"duration", "stackTrace"})
public final class VirtualThreadEndEvent extends MirrorEvent {

    @Label("Thread Id")
    public long javaThreadId;

}

src/java.base/share/classes/java/lang/VirtualThread.java:

            event.commit();
        }

        Object bindings = Thread.scopedValueBindings();
        try {
            runWith(bindings, task);
        } catch (Throwable exc) {
            dispatchUncaughtException(exc);
        } finally {
            // pop any remaining scopes from the stack, this may block
            StackableScope.popAll();

            // emit JFR event if enabled
            if (VirtualThreadEndEvent.isTurnedOn()) {
                var event = new VirtualThreadEndEvent();
                event.javaThreadId = threadId();
                event.commit();
            }
        }
    }

    /**
     * Mounts this virtual thread onto the current platform thread. On
     * return, the current thread is the virtual thread.
     */
    @ChangesCurrentThread

Event configuration settings across JFR profiles
Configuration enabled
default false
profiling false

Event fields with their types and descriptions
Field Type Description
javaThreadId long Thread Id

Examples 3
Example event data values and properties
javaThreadId long
48
startTime long: millis
487488445
Example event data values and properties
javaThreadId long
36
startTime long: millis
550081822
Example event data values and properties
javaThreadId long
44
startTime long: millis
603260356

SocketRead

throttle default profiling startTime duration 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/SocketReadEvent.java

Category: Java Application

Excludes in stack trace: java.io.InputStream, java.net.Socket$SocketInputStream, java.nio.channels.SocketChannel, sun.nio.ch.SocketInputStream

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Reading data from a socket

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/SocketReadEvent.java:

/**
 * A JFR event for socket read operations.  This event is mirrored in
 * {@code jdk.jfr.events.SocketReadEvent } where the metadata for the event is
 * provided with annotations.  Some of the methods are replaced by generated
 * methods when jfr is enabled.  Note that the order of the arguments of the
 * {@link #commit(long, long, String, String, int, long, long, boolean)} method
 * must be the same as the order of the fields.
 */
public class SocketReadEvent extends Event {

    // THE ORDER OF THE FOLLOWING FIELDS IS IMPORTANT!
    // The order must match the argument order of the generated commit method.
    public String host;
    public String address;
    public int port;
    public long timeout;
    public long bytesRead;
    public boolean endOfStream;

    /**

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);

src/jdk.jfr/share/classes/jdk/jfr/events/SocketReadEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "SocketRead")
@Label("Socket Read")
@Category("Java Application")
@Description("Reading data from a socket")
@StackFilter({"java.io.InputStream",
              "java.net.Socket$SocketInputStream",
              "java.nio.channels.SocketChannel",
              "sun.nio.ch.SocketInputStream"})
@Throttle
public final class SocketReadEvent extends MirrorEvent {

    @Label("Remote Host")
    public String host;

    @Label("Remote Address")
    public String address;

    @Label("Remote Port")
    public int port;

    @Label("Timeout Value")

src/java.base/share/classes/java/net/Socket.java:

        private final InputStream in;
        SocketInputStream(Socket parent, InputStream in) {
            this.parent = parent;
            this.in = in;
        }
        @Override
        public int read() throws IOException {
            byte[] a = new byte[1];
            int n = read(a, 0, 1);
            return (n > 0) ? (a[0] & 0xff) : -1;
        }
        @Override
        public int read(byte[] b, int off, int len) throws IOException {
            if (!SocketReadEvent.enabled()) {
                return implRead(b, off, len);
            }
            long start = SocketReadEvent.timestamp();
            int nbytes = implRead(b, off, len);
            SocketReadEvent.offer(start, nbytes, parent.getRemoteSocketAddress(), getSoTimeout());
            return nbytes;
        }

        private int implRead(byte[] b, int off, int len) throws IOException {
            try {
                return in.read(b, off, len);
            } catch (SocketTimeoutException e) {
                throw e;
            } catch (InterruptedIOException e) {
                Thread thread = Thread.currentThread();
                if (thread.isVirtual() && thread.isInterrupted()) {

src/java.base/share/classes/sun/nio/ch/SocketChannelImpl.java:

        } finally {
            readLock.unlock();
        }
    }

    @Override
    public int read(ByteBuffer buf) throws IOException {
        if (!SocketReadEvent.enabled()) {
            return implRead(buf);
        }
        long start = SocketReadEvent.timestamp();
        int nbytes = implRead(buf);
        SocketReadEvent.offer(start, nbytes, remoteAddress(), 0);
        return nbytes;
    }


    @Override
    public long read(ByteBuffer[] dsts, int offset, int length)
        throws IOException
    {
        if (!SocketReadEvent.enabled()) {
            return implRead(dsts, offset, length);
        }
        long start = SocketReadEvent.timestamp();
        long nbytes = implRead(dsts, offset, length);
        SocketReadEvent.offer(start, nbytes, remoteAddress(), 0);
        return nbytes;
    }

    /**
     * Marks the beginning of a write operation that might block.

src/java.base/share/classes/sun/nio/ch/SocketInputStream.java:

    private int implRead(byte[] b, int off, int len, int timeout) throws IOException {
        if (timeout > 0) {
            long nanos = MILLISECONDS.toNanos(timeout);
            return sc.blockingRead(b, off, len, nanos);
        } else {
            return sc.blockingRead(b, off, len, 0);
        }
    }

    @Override
    public int read(byte[] b, int off, int len) throws IOException {
        int timeout = timeoutSupplier.getAsInt();
        if (!SocketReadEvent.enabled()) {
            return implRead(b, off, len, timeout);
        }
        long start = SocketReadEvent.timestamp();
        int n = implRead(b, off, len, timeout);
        SocketReadEvent.offer(start, n, sc.remoteAddress(), timeout);
        return n;
    }

    @Override
    public int available() throws IOException {
        return sc.available();
    }

    @Override
    public void close() throws IOException {
        sc.close();

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold throttle
default true true 1 ms 100/s 25+
profiling true true 1 ms 300/s 25+

Event fields with their types and descriptions
Field Type Description
host string Remote Host
address string Remote Address
port int Remote Port
timeout long: millis Timeout Value
bytesRead long: bytes Bytes Read Number of bytes read from the socket
endOfStream boolean End of Stream If end of stream was reached

Examples 3
Example event data values and properties
address string
127.0.0.1
bytesRead long: bytes
64
endOfStream boolean
false
host string
127.0.0.1
port int
58232
startTime long: millis
2397402701
timeout long: millis
0
Example event data values and properties
address string
127.0.0.1
bytesRead long: bytes
64
endOfStream boolean
false
host string
127.0.0.1
port int
45099
startTime long: millis
1940375584
timeout long: millis
0
Example event data values and properties
address string
127.0.0.1
bytesRead long: bytes
64
endOfStream boolean
false
host string
127.0.0.1
port int
38919
startTime long: millis
2405726044
timeout long: millis
0

Java Application Statistics

JavaMonitorStatistics

default profiling startTime duration every chunk 25 27 28

Category: Java Application / Statistics

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

TRACE_REQUEST_FUNC(FinalizerStatistics) {
#if INCLUDE_MANAGEMENT
  JfrFinalizerStatisticsEvent::generate_events();
#else
  log_debug(jfr, system)("Unable to generate requestable event FinalizerStatistics. The required jvm feature 'management' is missing.");
#endif
}

TRACE_REQUEST_FUNC(NativeMemoryUsage) {
  JfrNativeMemoryEvent::send_type_events(timestamp());
}

TRACE_REQUEST_FUNC(NativeMemoryUsageTotal) {
  JfrNativeMemoryEvent::send_total_event(timestamp());
}

TRACE_REQUEST_FUNC(JavaMonitorStatistics) {
  EventJavaMonitorStatistics event;
  event.set_count(ObjectSynchronizer::in_use_list_count());
  event.commit();
}

Event configuration settings across JFR profiles
Configuration enabled period
default true everyChunk
profiling true everyChunk

Event fields with their types and descriptions
Field Type Description
count ulong Monitors in Use Current number of in-use monitors

Examples 3
Example event data values and properties
count ulong
2538
startTime long: millis
459222636115
Example event data values and properties
count ulong
4706
startTime long: millis
466102918278
Example event data values and properties
count ulong
449
startTime long: millis
23227592760

JavaThreadStatistics

default profiling startTime duration every chunk 11 17 21 25 27 28

Category: Java Application / Statistics

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  EventSwapSpace event;
  physical_memory_size_type total_swap_space = 0;
  // Return value ignored - defaulting to 0 on failure.
  (void)os::total_swap_space(total_swap_space);
  event.set_totalSize(static_cast<s8>(total_swap_space));
  physical_memory_size_type free_swap_space = 0;
  // Return value ignored - defaulting to 0 on failure.
  (void)os::free_swap_space(free_swap_space);
  event.set_freeSize(static_cast<s8>(free_swap_space));
  event.commit();
}

TRACE_REQUEST_FUNC(JavaThreadStatistics) {
  EventJavaThreadStatistics event;
  event.set_activeCount(ThreadService::get_live_thread_count());
  event.set_daemonCount(ThreadService::get_daemon_thread_count());
  event.set_accumulatedCount(ThreadService::get_total_thread_count());
  event.set_peakCount(ThreadService::get_peak_thread_count());
  event.commit();
}

TRACE_REQUEST_FUNC(GCHeapMemoryUsage) {
  MemoryUsage usage = Universe::heap()->memory_usage();
  EventGCHeapMemoryUsage event(UNTIMED);
  event.set_used(usage.used());

Event configuration settings across JFR profiles
Configuration enabled period
default true 1000 ms
profiling true 1000 ms

Event fields with their types and descriptions
Field Type Description
activeCount long Active Threads Number of live active threads including both daemon and non-daemon threads
daemonCount long Daemon Threads Number of live daemon threads
accumulatedCount long Accumulated Threads Number of threads created and also started since JVM start
peakCount long Peak Threads Peak live thread count since JVM start or when peak count was reset

Examples 3
Example event data values and properties
accumulatedCount long
1887
activeCount long
295
daemonCount long
294
peakCount long
297
startTime long: millis
471028589961
Example event data values and properties
accumulatedCount long
65
activeCount long
21
daemonCount long
16
peakCount long
22
startTime long: millis
3411950014
Example event data values and properties
accumulatedCount long
1919
activeCount long
65
daemonCount long
64
peakCount long
297
startTime long: millis
481851027813

ClassLoadingStatistics

default profiling startTime duration every chunk 11 17 21 25 27 28

Category: Java Application / Statistics

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

      event.set_used(usage.used());
      event.set_committed(usage.committed());
      event.set_max(usage.max_size());
      event.set_starttime(timestamp());
      event.set_endtime(timestamp());
      event.commit();
    }
  }
}


TRACE_REQUEST_FUNC(ClassLoadingStatistics) {
#if INCLUDE_MANAGEMENT
  EventClassLoadingStatistics event;
  event.set_loadedClassCount(ClassLoadingService::loaded_class_count());
  event.set_unloadedClassCount(ClassLoadingService::unloaded_class_count());
  event.commit();
#else
  log_debug(jfr, system)("Unable to generate requestable event ClassLoadingStatistics. The required jvm feature 'management' is missing.");
#endif
}

class JfrClassLoaderStatsClosure : public ClassLoaderStatsClosure {
public:
  JfrClassLoaderStatsClosure() : ClassLoaderStatsClosure(nullptr) {}

Event configuration settings across JFR profiles
Configuration enabled period
default true 1000 ms
profiling true 1000 ms

Event fields with their types and descriptions
Field Type Description
loadedClassCount long Loaded Class Count Number of classes loaded since JVM start
unloadedClassCount long Unloaded Class Count Number of classes unloaded since JVM start

Examples 3
Example event data values and properties
loadedClassCount long
132419
startTime long: millis
473301349657
unloadedClassCount long
3085
Example event data values and properties
loadedClassCount long
132747
startTime long: millis
476221595783
unloadedClassCount long
3111
Example event data values and properties
loadedClassCount long
4036
startTime long: millis
10583703545
unloadedClassCount long
193

ClassLoaderStatistics

default profiling startTime duration every chunk 11 17 21 25 27 28

Category: Java Application / Statistics

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  log_debug(jfr, system)("Unable to generate requestable event ClassLoadingStatistics. The required jvm feature 'management' is missing.");
#endif
}

class JfrClassLoaderStatsClosure : public ClassLoaderStatsClosure {
public:
  JfrClassLoaderStatsClosure() : ClassLoaderStatsClosure(nullptr) {}

  bool do_entry(oop const& key, ClassLoaderStats const& cls) {
    const ClassLoaderData* this_cld = cls._class_loader != nullptr ?
      java_lang_ClassLoader::loader_data_acquire(cls._class_loader) : nullptr;
    const ClassLoaderData* parent_cld = cls._parent != nullptr ?
      java_lang_ClassLoader::loader_data_acquire(cls._parent) : nullptr;
    EventClassLoaderStatistics event;
    event.set_classLoader(this_cld);
    event.set_parentClassLoader(parent_cld);
    event.set_classLoaderData((intptr_t)cls._cld);
    event.set_classCount(cls._classes_count);
    event.set_chunkSize(cls._chunk_sz);
    event.set_blockSize(cls._block_sz);
    event.set_hiddenClassCount(cls._hidden_classes_count);
    event.set_hiddenChunkSize(cls._hidden_chunk_sz);
    event.set_hiddenBlockSize(cls._hidden_block_sz);
    event.commit();
    return true;

Event configuration settings across JFR profiles
Configuration enabled period
default true everyChunk
profiling true everyChunk

Event fields with their types and descriptions
Field Type Description
classLoader ClassLoader Class Loader
parentClassLoader ClassLoader Parent Class Loader
classLoaderData ulong: address ClassLoaderData Pointer Pointer to the ClassLoaderData structure in the JVM
classCount long Classes Number of loaded classes
chunkSize ulong: bytes Total Chunk Size Total size of all allocated metaspace chunks (each chunk has several blocks)
blockSize ulong: bytes Total Block Size Total size of all allocated metaspace blocks (each chunk has several blocks)
hiddenClassCount long 15+ Hidden Classes Number of hidden classes
hiddenChunkSize ulong: bytes 15+ Total Hidden Classes Chunk Size Total size of all allocated metaspace chunks for hidden classes (each chunk has several blocks)
hiddenBlockSize ulong: bytes 15+ Total Hidden Classes Block Size Total size of all allocated metaspace blocks for hidden classes (each chunk has several blocks)

Examples 3
Example event data values and properties
blockSize ulong: bytes
13600
chunkSize ulong: bytes
16384
classCount long
2
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/codehaus/commons/compiler/util/reflect/ByteArrayClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/codehaus/commons/compiler/util/reflect
classLoaderData ulong: address
94556826867712
hiddenBlockSize ulong: bytes
0
hiddenChunkSize ulong: bytes
0
hiddenClassCount long
0
parentClassLoader ClassLoader
null
startTime long: millis
448951340982
Example event data values and properties
blockSize ulong: bytes
0
chunkSize ulong: bytes
0
classCount long
0
classLoader ClassLoader
null
classLoaderData ulong: address
0
hiddenBlockSize ulong: bytes
0
hiddenChunkSize ulong: bytes
0
hiddenClassCount long
0
parentClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
startTime long: millis
454658373824
Example event data values and properties
blockSize ulong: bytes
322400
chunkSize ulong: bytes
334848
classCount long
79
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
classLoaderData ulong: address
140367183975808
hiddenBlockSize ulong: bytes
0
hiddenChunkSize ulong: bytes
0
hiddenClassCount long
0
parentClassLoader ClassLoader
name string
platform
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$PlatformClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
startTime long: millis
23161971187

ThreadAllocationStatistics

default profiling startTime every chunk 11 17 21 25 27 28

Category: Java Application / Statistics

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  GrowableArray<uint64_t> allocated(initial_size);
  GrowableArray<traceid> thread_ids(initial_size);
  JfrTicks time_stamp = JfrTicks::now();
  JfrJavaThreadIterator iter;
  while (iter.has_next()) {
    JavaThread* const jt = iter.next();
    assert(jt != nullptr, "invariant");
    allocated.append(jt->cooked_allocated_bytes());
    thread_ids.append(JFR_JVM_THREAD_ID(jt));
  }

  // Write allocation statistics to buffer.
  for(int i = 0; i < thread_ids.length(); i++) {
    EventThreadAllocationStatistics event(UNTIMED);
    event.set_allocated(allocated.at(i));
    event.set_thread(thread_ids.at(i));
    event.set_starttime(time_stamp);
    event.set_endtime(time_stamp);
    event.commit();
  }
}

/**
 *  PhysicalMemory event represents:
 *

Event configuration settings across JFR profiles
Configuration enabled period
default true everyChunk
profiling true everyChunk

Event fields with their types and descriptions
Field Type Description
allocated ulong: bytes Allocated Approximate number of bytes allocated since thread start
thread Thread Thread

Examples 3
Example event data values and properties
allocated ulong: bytes
7421832
startTime long: millis
447754205507
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
RxComputationThreadPool-1
javaThreadId long
801
osName string
RxComputationThreadPool-1
osThreadId long
3171
virtual boolean
false
Example event data values and properties
allocated ulong: bytes
32
startTime long: millis
453049846731
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
SparkUI-1712
javaThreadId long
1712
osName string
SparkUI-1712
osThreadId long
4625
virtual boolean
false
Example event data values and properties
allocated ulong: bytes
1020363880
startTime long: millis
8024967526
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
pool-1-thread-3
javaThreadId long
36
osName string
pool-1-thread-3
osThreadId long
5046
virtual boolean
false

FinalizerStatistics

default profiling startTime end of every chunk 18 21 25 27 28

Category: Java Application / Statistics

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Per class statistics about finalizers

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrFinalizerStatisticsEvent.cpp:

static void send_event(const FinalizerEntry* fe, const InstanceKlass* ik, const JfrTicks& timestamp, Thread* thread) {
  assert(ik != nullptr, "invariant");
  assert(ik->has_finalizer(), "invariant");
  assert(thread != nullptr, "invariant");
  const char* const url = fe != nullptr ? fe->codesource() : nullptr;
  const traceid url_symbol_id = url != nullptr ? JfrSymbolTable::add(url) : 0;
  EventFinalizerStatistics event(UNTIMED);
  event.set_starttime(timestamp);
  event.set_endtime(timestamp);
  event.set_finalizableClass(ik);
  event.set_codeSource(url_symbol_id);
  if (fe == nullptr) {
    event.set_objects(0);
    event.set_totalFinalizersRun(0);
  } else {
    assert(fe->klass() == ik, "invariant");
    event.set_objects(fe->objects_on_heap());
    event.set_totalFinalizersRun(fe->total_finalizers_run());
  }
  event.commit();
}

void JfrFinalizerStatisticsEvent::send_unload_event(const InstanceKlass* ik) {
  if (!EventFinalizerStatistics::is_enabled()) {
    return;
  }
  Thread* const thread = Thread::current();
  ResourceMark rm(thread);
  send_event(FinalizerService::lookup(ik, thread), ik, JfrTicks::now(), thread);
}

// Finalizer events generated by the periodic task will all have the same timestamp.

class FinalizerStatisticsEventClosure : public FinalizerEntryClosure {
 private:

Event configuration settings across JFR profiles
Configuration enabled period
default true endChunk
profiling true endChunk

Event fields with their types and descriptions
Field Type Description
finalizableClass Class Class Overriding Finalize
codeSource Symbol Code Source URL from where the class was loaded
objects ulong Finalizable Objects on Heap Number of objects on heap that can be finalized
totalFinalizersRun ulong Finalizers Run Total number of finalizers run since JVM start

Examples 3
Example event data values and properties
codeSource Symbol
resource:///shared/netty-buffer-4.1.114.Final.jar
finalizableClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
24
name string
io/netty/buffer/PoolArena$DirectArena
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/buffer
objects ulong
16
startTime long: millis
452882529495
totalFinalizersRun ulong
0
Example event data values and properties
codeSource Symbol
resource:///unique/database/chronicle-core-2.26ea2.jar
finalizableClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
net/openhft/chronicle/core/io/CleaningRandomAccessFile
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
net/openhft/chronicle/core/io
objects ulong
0
startTime long: millis
456900193774
totalFinalizersRun ulong
2
Example event data values and properties
codeSource Symbol
resource:///shared/netty-buffer-4.1.114.Final.jar
finalizableClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
24
name string
io/netty/buffer/PoolArena$HeapArena
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/buffer
objects ulong
16
startTime long: millis
556760595205
totalFinalizersRun ulong
0

DeprecatedInvocation

default profiling startTime stackTrace 22 25 27 28

Category: Java Application / Statistics

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

A unique invocation of a method that is annotated with @Deprecated. Packages and modules that are deprecated are ignored. At most 10 000 invocation sites and only the first invocation from a class is guaranteed to be included.

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/jni/jfrJniMethod.cpp:

  JfrEventSetting::set_enabled(JfrCPUTimeSampleEvent, rate > 0);
  JfrCPUTimeThreadSampling::set_rate(rate);
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_set_cpu_period(JNIEnv* env, jclass jvm, jlong period_nanos))
  assert(period_nanos >= 0, "invariant");
  JfrEventSetting::set_enabled(JfrCPUTimeSampleEvent, period_nanos > 0);
  JfrCPUTimeThreadSampling::set_period(period_nanos);
JVM_END

NO_TRANSITION(void, jfr_set_miscellaneous(JNIEnv* env, jclass jvm, jlong event_type_id, jlong value))
  JfrEventSetting::set_miscellaneous(event_type_id, value);
  const JfrEventId typed_event_id = (JfrEventId)event_type_id;
  if (EventDeprecatedInvocation::eventId == typed_event_id) {
    JfrDeprecationManager::on_level_setting_update(value);
  }
NO_TRANSITION_END

NO_TRANSITION(jboolean, jfr_should_rotate_disk(JNIEnv* env, jclass jvm))
  return JfrChunkRotation::should_rotate() ? JNI_TRUE : JNI_FALSE;
NO_TRANSITION_END

NO_TRANSITION(jlong, jfr_get_type_id_from_string(JNIEnv * env, jclass jvm, jstring type))
  const char* type_name = env->GetStringUTFChars(type, nullptr);
  jlong id = JfrType::name_to_id(type_name);

Event configuration settings across JFR profiles
Configuration enabled level stackTrace
default true forRemoval true
profiling true forRemoval true

Event fields with their types and descriptions
Field Type Description
method Method Deprecated Method
invocationTime Ticks Invocation Time The time the deprecated method was invoked for the first time
forRemoval boolean For Removal

Examples 3
Example event data values and properties
forRemoval boolean
true
invocationTime Ticks
433754527567
method Method
descriptor string
(Ljava/lang/Object;JLjava/lang/Object;JJ)V
hidden boolean
false
modifiers int
1
name string
copyMemory
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
sun/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.unsupported
name string
jdk.unsupported
version string
25.0.4.1
name string
sun/misc
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
34
lineNumber int
188
method Method
descriptor string
(Ljava/lang/Object;JLjava/lang/Object;JJ)V
hidden boolean
false
modifiers int
9
name string
copyMemory
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
org/apache/spark/unsafe/Platform
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/unsafe
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
449441346061
Example event data values and properties
forRemoval boolean
true
invocationTime Ticks
1329652614
method Method
descriptor string
()V
hidden boolean
false
modifiers int
9
name string
runFinalization
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/System
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
32
lineNumber int
375
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
spawnFinalizable
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
true
startTime long: millis
25528525357
Example event data values and properties
forRemoval boolean
true
invocationTime Ticks
441627297902
method Method
descriptor string
(Ljava/security/PrivilegedAction;)Ljava/lang/Object;
hidden boolean
false
modifiers int
9
name string
doPrivileged
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/security/AccessController
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/security
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
102
lineNumber int
99
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
<clinit>
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
16
name string
io/netty/util/internal/PlatformDependent0
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/util/internal
type FrameType
Interpreted
truncated boolean
true
startTime long: millis
454981288785

ExceptionStatistics

default profiling startTime duration 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/ExceptionStatisticsEvent.java

Category: Java Application / Statistics

Number of objects derived from java.lang.Throwable that have been created

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/ThrowableTracer.java:

                ErrorThrownEvent.commit(timestamp, message, clazz);
            }
            if (ExceptionThrownEvent.shouldThrottleCommit(timestamp)) {
                ExceptionThrownEvent.commit(timestamp, message, clazz);
            }
        }
        numThrowables.incrementAndGet();
    }

    public static void traceThrowable(Class<?> clazz, String message) {
        if (ExceptionThrownEvent.enabled()) {
            long timestamp = ErrorThrownEvent.timestamp();
            if (ExceptionThrownEvent.shouldThrottleCommit(timestamp)) {
                ExceptionThrownEvent.commit(timestamp, message, clazz);
            }
        }
        numThrowables.incrementAndGet();
    }

    public static void emitStatistics() {
        long timestamp = ExceptionStatisticsEvent.timestamp();
        ExceptionStatisticsEvent.commit(timestamp, numThrowables.get());
    }
}

src/java.base/share/classes/jdk/internal/event/ExceptionStatisticsEvent.java:

package jdk.internal.event;

/**
 * Event recording number of exceptions that has been created.
 */
public class ExceptionStatisticsEvent extends Event {

    public long throwables;

    public static void commit(long timestamp, long throwables) {
        // Generated by JFR
    }

    public static boolean enabled() {
        // Generated by JFR
        return false;
    }

    public static long timestamp() {
        // Generated by JFR
        return 0;
    }
}

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
        register("jdk.internal.event.FinalFieldMutationEvent", FinalFieldMutationEvent.class);
    };

    private static void register(String eventClassName, Class<? extends MirrorEvent> mirrorClass) {
        mirrorLookup.put(eventClassName, mirrorClass);
    }

    static Class<? extends MirrorEvent> find(Class<? extends jdk.internal.event.Event> eventClass) {
        return find(Utils.isJDKClass(eventClass), eventClass.getName());
    }

src/jdk.jfr/share/classes/jdk/jfr/events/ExceptionStatisticsEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.MirrorEvent;
import jdk.jfr.internal.RemoveFields;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "ExceptionStatistics")
@Label("Exception Statistics")
@Category({ "Java Application", "Statistics" })
@Description("Number of objects derived from java.lang.Throwable that have been created")
@RemoveFields({"duration", "eventThread", "stackTrace"})
public final class ExceptionStatisticsEvent extends MirrorEvent {

    @Label("Exceptions Created")
    public long throwables;
}

Event configuration settings across JFR profiles
Configuration enabled period
default true 1000 ms
profiling true 1000 ms

Event fields with their types and descriptions
Field Type Description
throwables long Exceptions Created

Examples 3
Example event data values and properties
startTime long: millis
22876845159
throwables long
1451
Example event data values and properties
startTime long: millis
465815224221
throwables long
2355499
Example event data values and properties
startTime long: millis
455797991894
throwables long
2354745

DirectBufferStatistics

default profiling startTime duration stackTrace 15 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/DirectBufferStatisticsEvent.java

Category: Java Application / Statistics

Statistics of direct buffer

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.SecurityProviderServiceEvent.class,
        jdk.internal.event.SerializationMisdeclarationEvent.class,
        jdk.internal.event.SocketReadEvent.class,
        jdk.internal.event.SocketWriteEvent.class,
        jdk.internal.event.ThreadSleepEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.VirtualThreadStartEvent.class,
        jdk.internal.event.VirtualThreadEndEvent.class,
        jdk.internal.event.VirtualThreadSubmitFailedEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,
        jdk.internal.event.FinalFieldMutationEvent.class,
        DirectBufferStatisticsEvent.class,
        InitialSecurityPropertyEvent.class,
        MethodTraceEvent.class,
        MethodTimingEvent.class,
    };

    private static final Runnable emitExceptionStatistics = JDKEvents::emitExceptionStatistics;
    private static final Runnable emitDirectBufferStatistics = JDKEvents::emitDirectBufferStatistics;
    private static final Runnable emitContainerConfiguration = JDKEvents::emitContainerConfiguration;
    private static final Runnable emitContainerCPUUsage = JDKEvents::emitContainerCPUUsage;
    private static final Runnable emitContainerCPUThrottling = JDKEvents::emitContainerCPUThrottling;
    private static final Runnable emitContainerMemoryUsage = JDKEvents::emitContainerMemoryUsage;

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

    private static final Runnable emitInitialSecurityProperties = JDKEvents::emitInitialSecurityProperties;
    private static final Runnable emitMethodTiming = JDKEvents::emitMethodTiming;
    private static Metrics containerMetrics = null;
    private static boolean initializationTriggered;

    @SuppressWarnings("unchecked")
    public static synchronized void initialize() {
        try {
            if (initializationTriggered == false) {
                for (Class<?> eventClass : eventClasses) {
                    MetadataRepository.getInstance().register((Class<? extends Event>) eventClass);
                }
                PeriodicEvents.addJavaEvent(jdk.internal.event.ExceptionStatisticsEvent.class, emitExceptionStatistics);
                PeriodicEvents.addJavaEvent(DirectBufferStatisticsEvent.class, emitDirectBufferStatistics);
                PeriodicEvents.addJavaEvent(InitialSecurityPropertyEvent.class, emitInitialSecurityProperties);
                PeriodicEvents.addJavaEvent(MethodTimingEvent.class, emitMethodTiming);

                initializeContainerEvents();
                JFRTracing.enable();
                initializationTriggered = true;
            }
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not initialize JDK events. " + e.getMessage());
        }
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        PeriodicEvents.removeEvent(emitExceptionStatistics);
        PeriodicEvents.removeEvent(emitDirectBufferStatistics);
        PeriodicEvents.removeEvent(emitInitialSecurityProperties);
        PeriodicEvents.removeEvent(emitMethodTiming);

        PeriodicEvents.removeEvent(emitContainerConfiguration);
        PeriodicEvents.removeEvent(emitContainerCPUUsage);
        PeriodicEvents.removeEvent(emitContainerCPUThrottling);
        PeriodicEvents.removeEvent(emitContainerMemoryUsage);
        PeriodicEvents.removeEvent(emitContainerIOUsage);
    }

    private static void emitDirectBufferStatistics() {
        DirectBufferStatisticsEvent e = new DirectBufferStatisticsEvent();
        e.commit();
    }

    private static void emitInitialSecurityProperties() {
        Properties p = SharedSecrets.getJavaSecurityPropertiesAccess().getInitialProperties();
        if (p != null) {
            for (String key : p.stringPropertyNames()) {
                InitialSecurityPropertyEvent e = new InitialSecurityPropertyEvent();
                e.key = key;
                e.value = p.getProperty(key);
                e.commit();

src/jdk.jfr/share/classes/jdk/jfr/events/DirectBufferStatisticsEvent.java:

package jdk.jfr.events;

import jdk.internal.misc.VM;
import jdk.internal.misc.VM.BufferPool;

import jdk.jfr.*;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "DirectBufferStatistics")
@Label("Direct Buffer Statistics")
@Description("Statistics of direct buffer")
public final class DirectBufferStatisticsEvent extends AbstractBufferStatisticsEvent {

    private static final BufferPool DIRECT_BUFFER_POOL = findPoolByName("direct");

    public DirectBufferStatisticsEvent() {
        super(DIRECT_BUFFER_POOL);
        this.maxCapacity = VM.maxDirectMemory();
    }

    @Label("Maximum Capacity")
    @Description("Maximum direct buffer capacity the process can use")
    @DataAmount
    final long maxCapacity;
}

Event configuration settings across JFR profiles
Configuration enabled period
default true 5 s
profiling true 5 s

Examples 3
Example event data values and properties
startTime long: millis
484104996495
Example event data values and properties
startTime long: millis
15750895233
Example event data values and properties
startTime long: millis
504339492742

Java Development Kit

TLSHandshake

startTime duration 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/TLSHandshakeEvent.java

Category: Java Development Kit / Security

Excludes in stack trace: sun.security.ssl.Finished::recordEvent

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Parameters used in TLS Handshake

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/TLSHandshakeEvent.java:

package jdk.internal.event;

/**
 * Event recording details of successful TLS handshakes.
 */

public final class TLSHandshakeEvent extends Event {
    public String peerHost;
    public int peerPort;
    public String protocolVersion;
    public String cipherSuite;
    public long certificateId;
}

src/java.base/share/classes/sun/security/ssl/Finished.java:

                shc.conContext.finishHandshake();
            }
            recordEvent(shc.conContext.conSession);

            //
            // produce
            if (SSLConfiguration.serverNewSessionTicketCount > 0) {
                NewSessionTicket.t13PosthandshakeProducer.produce(shc);
            }
        }
    }

    private static void recordEvent(SSLSessionImpl session) {
        TLSHandshakeEvent event = new TLSHandshakeEvent();
        if (event.shouldCommit() || EventHelper.isLoggingSecurity()) {
            int hash = 0;
            try {
                // use hash code for Id
                hash = session
                        .getCertificateChain()[0]
                        .hashCode();
            } catch (SSLPeerUnverifiedException e) {
                 // not verified msg
            }
            long peerCertificateId = Integer.toUnsignedLong(hash);

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
        register("jdk.internal.event.FinalFieldMutationEvent", FinalFieldMutationEvent.class);
    };

src/jdk.jfr/share/classes/jdk/jfr/events/TLSHandshakeEvent.java:

@Category({"Java Development Kit", "Security"})
@Label("TLS Handshake")
@Name("jdk.TLSHandshake")
@Description("Parameters used in TLS Handshake")
@RemoveFields("duration")
@StackFilter("sun.security.ssl.Finished::recordEvent")
public final class TLSHandshakeEvent extends MirrorEvent {
    @Label("Peer Host")
    public String peerHost;

    @Label("Peer Port")
    public int peerPort;

    @Label("Protocol Version")
    public String protocolVersion;

    @Label("Cipher Suite")
    public String cipherSuite;

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default false true
profiling false true

Event fields with their types and descriptions
Field Type Description
peerHost string Peer Host
peerPort int Peer Port
protocolVersion string Protocol Version
cipherSuite string Cipher Suite
certificateId ulong: certificateId Certificate Id Peer Certificate Id

Examples 3
Example event data values and properties
certificateId ulong: certificateId
998794918
cipherSuite string
TLS_AES_256_GCM_SHA384
peerHost string
example.com
peerPort int
443
protocolVersion string
TLSv1.3
startTime long: millis
832755528
Example event data values and properties
certificateId ulong: certificateId
998794918
cipherSuite string
TLS_AES_256_GCM_SHA384
peerHost string
example.com
peerPort int
443
protocolVersion string
TLSv1.3
startTime long: millis
1104300297
Example event data values and properties
certificateId ulong: certificateId
998794918
cipherSuite string
TLS_AES_256_GCM_SHA384
peerHost string
example.com
peerPort int
443
protocolVersion string
TLSv1.3
startTime long: millis
1108105596

SecurityProviderService

startTime duration 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/SecurityProviderServiceEvent.java

Category: Java Development Kit / Security

Excludes in stack trace: java.security.Provider::getService

Details of Provider.getInstance(String type, String algorithm) calls

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/SecurityProviderServiceEvent.java:

package jdk.internal.event;

/**
 * Event recording details of Provider.getService(String type, String algorithm) calls
 */

public final class SecurityProviderServiceEvent extends Event {
    private static final SecurityProviderServiceEvent EVENT = new SecurityProviderServiceEvent();

    /**
     * Returns {@code true} if event is enabled, {@code false} otherwise.
     */
    public static boolean isTurnedOn() {
        return EVENT.isEnabled();
    }

    public String type;
    public String algorithm;
    public String provider;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

 * This class registers all mirror events.
 */
final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);

src/jdk.jfr/share/classes/jdk/jfr/events/SecurityProviderServiceEvent.java:

@Category({"Java Development Kit", "Security"})
@Label("Security Provider Instance Request")
@Name("jdk.SecurityProviderService")
@Description("Details of Provider.getInstance(String type, String algorithm) calls")
@RemoveFields("duration")
@StackFilter({"java.security.Provider::getService"})
public final class SecurityProviderServiceEvent extends MirrorEvent {
    @Label("Type of Service")
    public String type;

    @Label("Algorithm Name")
    public String algorithm;

    @Label("Security Provider")
    public String provider;
}

src/java.base/share/classes/java/security/Provider.java:

            key = new ServiceKey(type, algorithm, false);
            previousKey.set(key);
        }

        Service s = serviceMap.get(key);
        if (s == null) {
            s = legacyMap.get(key);
            if (s != null && !s.isValid()) {
                legacyMap.remove(key, s);
                return null;
            }
        }

        if (s != null && SecurityProviderServiceEvent.isTurnedOn()) {
            var e  = new SecurityProviderServiceEvent();
            e.provider = getName();
            e.type = type;
            e.algorithm = algorithm;
            e.commit();
        }

        return s;
    }

    // ServiceKey from previous getService() call
    // by re-using it if possible we avoid allocating a new object

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default false true
profiling false true

Event fields with their types and descriptions
Field Type Description
type string Type of Service
algorithm string Algorithm Name
provider string Security Provider

Examples 3
Example event data values and properties
algorithm string
MD5
provider string
SUN
startTime long: millis
490496135712
type string
MessageDigest
Example event data values and properties
algorithm string
X509
provider string
SUN
startTime long: millis
747426850
type string
CertificateFactory
Example event data values and properties
algorithm string
MD5
provider string
SUN
startTime long: millis
497755251223
type string
MessageDigest

SecurityPropertyModification

startTime duration 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/SecurityPropertyModificationEvent.java

Category: Java Development Kit / Security

Excludes in stack trace: java.security.Security::setProperty

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Modification of Security property

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/SecurityPropertyModificationEvent.java:

package jdk.internal.event;

/**
 * Event details relating to the modification of a Security property.
 */

public final class SecurityPropertyModificationEvent extends Event {
    public String key;
    public String value;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

/**
 * This class registers all mirror events.
 */
final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);

src/jdk.jfr/share/classes/jdk/jfr/events/SecurityPropertyModificationEvent.java:

package jdk.jfr.events;

import jdk.jfr.*;
import jdk.jfr.internal.MirrorEvent;
import jdk.jfr.internal.RemoveFields;

@Category({"Java Development Kit", "Security"})
@Label("Security Property Modification")
@Name("jdk.SecurityPropertyModification")
@Description("Modification of Security property")
@RemoveFields("duration")
@StackFilter({"java.security.Security::setProperty"})
public final class SecurityPropertyModificationEvent extends MirrorEvent {
    @Label("Key")
    public String key;

    @Label("Value")
    public String value;
}

src/java.base/share/classes/java/security/Security.java:

     * @param datum the value of the property to be set.
     *
     * @throws  NullPointerException if key or datum is {@code null}
     * @throws  IllegalArgumentException if key is reserved and cannot be
     *          used as a Security property name. Reserved keys are:
     *          "include".
     *
     * @see #getProperty
     */
    public static void setProperty(String key, String datum) {
        SecPropLoader.checkReservedKey(key);
        props.put(key, datum);

        SecurityPropertyModificationEvent spe = new SecurityPropertyModificationEvent();
        // following is a no-op if event is disabled
        spe.key = key;
        spe.value = datum;
        spe.commit();

        if (EventHelper.isLoggingSecurity()) {
            EventHelper.logSecurityPropertyEvent(key, datum);
        }
    }

    private static class Criteria {

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default false true
profiling false true

Event fields with their types and descriptions
Field Type Description
key string Key
value string Value

Examples 3
Example event data values and properties
key string
jdk.disabled.namedCurves
startTime long: millis
1175633602
value string
secp112r1
Example event data values and properties
key string
jdk.disabled.namedCurves
startTime long: millis
891669707
value string
secp112r1
Example event data values and properties
key string
jdk.disabled.namedCurves
startTime long: millis
1229926713
value string
secp112r1

SerializationMisdeclaration

profiling startTime duration 23 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/SerializationMisdeclarationEvent.java

Category: Java Development Kit / Serialization

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Methods and fields misdeclarations. The checks are usually performed just once per serializable class, the first time it is used by serialization. Under high memory pressure, a class might be re-checked again.

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/SerializationMisdeclarationEvent.java:

package jdk.internal.event;

/**
 * A JFR event for serialization misdeclarations.
 * This event is mirrored in {@code jdk.jfr.events.SerializationMisdeclarationEvent}
 * where the metadata for the event is provided with annotations.
 * Some of the methods are replaced by generated methods when jfr is enabled.
 * Note that the order of the arguments of the {@link #commit(long,Class,String)}
 * method must be the same as the order of the fields.
 */
public class SerializationMisdeclarationEvent extends Event {

    public Class<?> misdeclaredClass;
    public String message;

    /**
     * Commit a serialization misdeclaration event.
     * The implementation of this method is generated automatically if jfr is enabled.
     * The order of the fields must be the same as the parameters in this method.
     * {@code commit(long,Class,String)}
     *
     * @param start             timestamp of the start of the operation
     * @param misdeclaredClass  the affected class
     * @param message           the specific event message

src/java.base/share/classes/java/io/ObjectStreamClass.java:

        if (isRecord && canonicalCtr == null) {
            deserializeEx = new ExceptionInfo(name, "record canonical constructor not found");
        } else {
            for (int i = 0; i < fields.length; i++) {
                if (fields[i].getField() == null) {
                    defaultSerializeEx = new ExceptionInfo(
                        name, "unmatched serializable field(s) declared");
                }
            }
        }
        initialized = true;

        if (SerializationMisdeclarationEvent.enabled() && serializable) {
            SerializationMisdeclarationChecker.checkMisdeclarations(cl);
        }
    }

    /**
     * Creates blank class descriptor which should be initialized via a
     * subsequent call to initProxy(), initNonProxy() or readNonProxy().
     */
    ObjectStreamClass() {
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

 */
final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);

src/jdk.jfr/share/classes/jdk/jfr/events/SerializationMisdeclarationEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "SerializationMisdeclaration")
@Label("Serialization Misdeclaration")
@Category({"Java Development Kit", "Serialization"})
@Description("Methods and fields misdeclarations." +
        " The checks are usually performed just once per serializable class," +
        " the first time it is used by serialization." +
        " Under high memory pressure, a class might be re-checked again.")
@RemoveFields({"duration", "stackTrace", "eventThread"})
public final class SerializationMisdeclarationEvent extends MirrorEvent {

    @Label("Misdeclared Class")
    public Class<?> misdeclaredClass;

    @Label("Message")
    public String message;

}

Event configuration settings across JFR profiles
Configuration enabled
default false
profiling true

Event fields with their types and descriptions
Field Type Description
misdeclaredClass Class Misdeclared Class
message string Message

Examples 3
Example event data values and properties
message string
serialVersionUID should be declared explicitly as a private static final long field
misdeclaredClass Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
0
name string
jfr_sample/Main$4
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
startTime long: millis
1446784137
Example event data values and properties
message string
serialVersionUID should be declared explicitly as a private static final long field
misdeclaredClass Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
0
name string
jfr_sample/Main$4
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
startTime long: millis
1014639539
Example event data values and properties
message string
serialVersionUID should be declared explicitly as a private static final long field
misdeclaredClass Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
0
name string
jfr_sample/Main$4
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
startTime long: millis
1421166683

X509Validation

startTime duration 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/X509ValidationEvent.java

Category: Java Development Kit / Security

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Serial numbers from X.509 Certificates forming chain of trust

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/X509ValidationEvent.java:

package jdk.internal.event;

/**
 * Event recording details of X.509 Certificate serial numbers
 * used in X509 cert path validation.
 */

public final class X509ValidationEvent extends Event {
    public long certificateId;
    public int certificatePosition;
    public long validationCounter;
}

src/java.base/share/classes/sun/security/provider/certpath/PKIXCertPathValidator.java:

        // only add a RevocationChecker if revocation is enabled and
        // a PKIXRevocationChecker has not already been added
        if (params.revocationEnabled() && !revCheckerAdded) {
            certPathCheckers.add(new RevocationChecker(anchor, params));
        }
        // add user-specified checkers
        certPathCheckers.addAll(checkers);

        PKIXMasterCertPathValidator.validate(params.certPath(),
                                             params.certificates(),
                                             certPathCheckers);

        X509ValidationEvent xve = new X509ValidationEvent();
        if (xve.shouldCommit() || EventHelper.isLoggingSecurity()) {
            long[] certIds = params.certificates().stream()
                    .mapToInt(Certificate::hashCode)
                    .mapToLong(Integer::toUnsignedLong)
                    .toArray();
            int hash = (anchorCert != null) ?
                anchorCert.hashCode() : anchor.getCAPublicKey().hashCode();
            long anchorCertId = Integer.toUnsignedLong(hash);
            if (xve.shouldCommit()) {
                xve.certificateId = anchorCertId;
                int certificatePos = 1; // most trusted CA

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
        register("jdk.internal.event.FinalFieldMutationEvent", FinalFieldMutationEvent.class);
    };

    private static void register(String eventClassName, Class<? extends MirrorEvent> mirrorClass) {
        mirrorLookup.put(eventClassName, mirrorClass);
    }

    static Class<? extends MirrorEvent> find(Class<? extends jdk.internal.event.Event> eventClass) {

src/jdk.jfr/share/classes/jdk/jfr/events/X509ValidationEvent.java:

package jdk.jfr.events;

import jdk.jfr.*;
import jdk.jfr.internal.MirrorEvent;
import jdk.jfr.internal.RemoveFields;

@Category({"Java Development Kit", "Security"})
@Label("X509 Validation")
@Name("jdk.X509Validation")
@Description("Serial numbers from X.509 Certificates forming chain of trust")
@RemoveFields("duration")
public final class X509ValidationEvent extends MirrorEvent {
    @CertificateId
    @Label("Certificate Id")
    @Unsigned
    public long certificateId;

    @Label("Certificate Position")
    @Description("Certificate position in chain of trust, 1 = trust anchor")
    public int certificatePosition;

    @Label("Validation Counter")
    public long validationCounter;
}

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default false true
profiling false true

Event fields with their types and descriptions
Field Type Description
certificateId ulong: certificateId Certificate Id
certificatePosition int Certificate Position Certificate position in chain of trust, 1 = trust anchor
validationCounter long Validation Counter

Examples 3
Example event data values and properties
certificateId ulong: certificateId
2389201834
certificatePosition int
2
startTime long: millis
1064360137
validationCounter long
1
Example event data values and properties
certificateId ulong: certificateId
1917811103
certificatePosition int
3
startTime long: millis
802444584
validationCounter long
1
Example event data values and properties
certificateId ulong: certificateId
998794918
certificatePosition int
4
startTime long: millis
1067334992
validationCounter long
1

Deserialization

startTime duration 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/DeserializationEvent.java

Category: Java Development Kit / Serialization

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Results of deserialization and ObjectInputFilter checks

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/DeserializationEvent.java:

package jdk.internal.event;

/**
 * Event details relating to deserialization.
 */

public final class DeserializationEvent extends Event {
    public boolean filterConfigured;
    public String filterStatus;
    public Class<?> type;
    public int arrayLength;
    public long objectReferences;
    public long depth;
    public long bytesRead;
    public Class<?> exceptionType;
    public String exceptionMessage;
}

src/java.base/share/classes/java/io/ObjectInputStream.java:

        ObjectInputFilter next = Config.getSerialFilterFactory()
                .apply(serialFilter, filter);
        if (serialFilter != null && next == null) {
            throw new IllegalStateException("filter can not be replaced with null filter");
        }
        serialFilter = next;
    }

    /**
     * Invokes the deserialization filter if non-null.
     *
     * If the filter rejects or an exception is thrown, throws InvalidClassException.
     *
     * Logs and/or commits a {@code DeserializationEvent}, if configured.
     *
     * @param clazz the class; may be null
     * @param arrayLength the array length requested; use {@code -1} if not creating an array
     * @throws InvalidClassException if it rejected by the filter or
     *        a {@link RuntimeException} is thrown
     */
    private void filterCheck(Class<?> clazz, int arrayLength)
            throws InvalidClassException {
        // Info about the stream is not available if overridden by subclass, return 0
        long bytesRead = (bin == null) ? 0 : bin.getBytesRead();
        RuntimeException ex = null;

src/java.base/share/classes/java/io/ObjectInputStream.java:

                status = ObjectInputFilter.Status.REJECTED;
                ex = e;
            }
            if (Logging.filterLogger != null) {
                // Debug logging of filter checks that fail; Tracing for those that succeed
                Logging.filterLogger.log(status == null || status == ObjectInputFilter.Status.REJECTED
                                ? Logger.Level.DEBUG
                                : Logger.Level.TRACE,
                        "ObjectInputFilter {0}: {1}, array length: {2}, nRefs: {3}, depth: {4}, bytes: {5}, ex: {6}",
                        status, clazz, arrayLength, totalObjectRefs, depth, bytesRead,
                        Objects.toString(ex, "n/a"));
            }
        }
        DeserializationEvent event = new DeserializationEvent();
        if (event.shouldCommit()) {
            event.filterConfigured = serialFilter != null;
            event.filterStatus = status != null ? status.name() : null;
            event.type = clazz;
            event.arrayLength = arrayLength;
            event.objectReferences = totalObjectRefs;
            event.depth = depth;
            event.bytesRead = bytesRead;
            event.exceptionType = ex != null ? ex.getClass() : null;
            event.exceptionMessage = ex != null ? ex.getMessage() : null;
            event.commit();

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

/**
 * This class registers all mirror events.
 */
final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);

src/jdk.jfr/share/classes/jdk/jfr/events/DeserializationEvent.java:

@Category({"Java Development Kit", "Serialization"})
@Label("Deserialization")
@Name("jdk.Deserialization")
@Description("Results of deserialization and ObjectInputFilter checks")
@RemoveFields("duration")
public final class DeserializationEvent extends MirrorEvent {

    @Label("Filter Configured")
    public boolean filterConfigured;

    @Label("Filter Status")
    public String filterStatus;

    @Label ("Type")
    public Class<?> type;

    @Label ("Array Length")

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default false true
profiling false true

Event fields with their types and descriptions
Field Type Description
filterConfigured boolean Filter Configured
filterStatus string Filter Status
type Class Type
arrayLength int Array Length
objectReferences long Object References
depth long Depth
bytesRead long Bytes Read
exceptionType Class Exception Type
exceptionMessage string Exception Message

Examples 3
Example event data values and properties
arrayLength int
-1
bytesRead long
9104
depth long
2
exceptionMessage string
null
exceptionType Class
null
filterConfigured boolean
false
filterStatus string
null
objectReferences long
25
startTime long: millis
447538229999
type Class
null
Example event data values and properties
arrayLength int
64
bytesRead long
15109
depth long
14
exceptionMessage string
null
exceptionType Class
null
filterConfigured boolean
false
filterStatus string
null
objectReferences long
206
startTime long: millis
452974600001
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[D
package Package
null
Example event data values and properties
arrayLength int
-1
bytesRead long
45
depth long
1
exceptionMessage string
null
exceptionType Class
null
filterConfigured boolean
false
filterStatus string
null
objectReferences long
1
startTime long: millis
1141698559
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/ArrayList
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util

X509Certificate

startTime duration 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/X509CertificateEvent.java

Category: Java Development Kit / Security

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Details of X.509 Certificate parsed by JDK

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/X509CertificateEvent.java:

package jdk.internal.event;


/**
 * Event recording details of X.509 Certificate.
 */

public final class X509CertificateEvent extends Event {
    private static final X509CertificateEvent EVENT = new X509CertificateEvent();

    /**
     * Returns {@code true} if event is enabled, {@code false} otherwise.
     */
    public static boolean isTurnedOn() {
        return EVENT.isEnabled();
    }

    public String algorithm;
    public String serialNumber;
    public String subject;
    public String issuer;
    public String keyType;
    public int keyLength;
    public long certificateId;

src/java.base/share/classes/sun/security/jca/JCAUtil.java:

        SecureRandom result = def;
        if (result == null) {
            synchronized (JCAUtil.class) {
                result = def;
                if (result == null) {
                    def = result = new SecureRandom();
                }
            }
        }
        return result;
    }

    public static void tryCommitCertEvent(Certificate cert) {
        if ((X509CertificateEvent.isTurnedOn() || EventHelper.isLoggingSecurity()) &&
                (cert instanceof X509Certificate x509)) {
            PublicKey pKey = x509.getPublicKey();
            String algId = x509.getSigAlgName();
            String serNum = Debug.toString(x509.getSerialNumber());
            String subject = x509.getSubjectX500Principal().toString();
            String issuer = x509.getIssuerX500Principal().toString();
            String keyType = pKey.getAlgorithm();
            int length = KeyUtil.getKeySize(pKey);
            int hashCode = x509.hashCode();
            long certifcateId = Integer.toUnsignedLong(hashCode);
            long beginDate = x509.getNotBefore().getTime();
            long endDate = x509.getNotAfter().getTime();
            if (X509CertificateEvent.isTurnedOn()) {
                X509CertificateEvent xce = new X509CertificateEvent();
                xce.algorithm = algId;
                xce.serialNumber = serNum;
                xce.subject = subject;
                xce.issuer = issuer;
                xce.keyType = keyType;
                xce.keyLength = length;
                xce.certificateId = certifcateId;
                xce.validFrom = beginDate;
                xce.validUntil = endDate;
                xce.commit();
            }

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
        register("jdk.internal.event.FinalFieldMutationEvent", FinalFieldMutationEvent.class);
    };

    private static void register(String eventClassName, Class<? extends MirrorEvent> mirrorClass) {
        mirrorLookup.put(eventClassName, mirrorClass);
    }

src/jdk.jfr/share/classes/jdk/jfr/events/X509CertificateEvent.java:

package jdk.jfr.events;

import jdk.jfr.*;
import jdk.jfr.internal.MirrorEvent;
import jdk.jfr.internal.RemoveFields;

@Category({"Java Development Kit", "Security"})
@Label("X509 Certificate")
@Name("jdk.X509Certificate")
@Description("Details of X.509 Certificate parsed by JDK")
@RemoveFields("duration")
public final class X509CertificateEvent extends MirrorEvent {
    @Label("Signature Algorithm")
    public String algorithm;

    @Label("Serial Number")
    public String serialNumber;

    @Label("Subject")
    public String subject;

    @Label("Issuer")
    public String issuer;

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default false true
profiling false true

Event fields with their types and descriptions
Field Type Description
algorithm string Signature Algorithm
serialNumber string Serial Number
subject string Subject
issuer string Issuer
keyType string Key Type
keyLength int Key Length
certificateId ulong: certificateId Certificate Id
validFrom long: epochmillis Valid From
validUntil long: epochmillis Valid Until

Examples 3
Example event data values and properties
algorithm string
SHA384withECDSA
certificateId ulong: certificateId
792571453
issuer string
CN=Certainly Root E1, O=Certainly, C=US
keyLength int
384
keyType string
EC
serialNumber string
06:25:33:b1:47:03:33:27:5c:f9:8d:9a:b9:bf:cc:f8
startTime long: millis
736209714
subject string
CN=Certainly Root E1, O=Certainly, C=US
validFrom long: epochmillis
1617235200000
validUntil long: epochmillis
2406153600000
Example event data values and properties
algorithm string
SHA1withRSA
certificateId ulong: certificateId
771312514
issuer string
CN=SwissSign Platinum CA - G2, O=SwissSign AG, C=CH
keyLength int
4096
keyType string
RSA
serialNumber string
4e:b2:00:67:0c:03:5d:4f
startTime long: millis
586212326
subject string
CN=SwissSign Platinum CA - G2, O=SwissSign AG, C=CH
validFrom long: epochmillis
1161765360000
validUntil long: epochmillis
2108536560000
Example event data values and properties
algorithm string
SHA256withRSA
certificateId ulong: certificateId
733875591
issuer string
CN=GlobalSign, O=GlobalSign, OU=GlobalSign Root CA - R3
keyLength int
2048
keyType string
RSA
serialNumber string
04:00:00:00:00:01:21:58:53:08:a2
startTime long: millis
694906117
subject string
CN=GlobalSign, O=GlobalSign, OU=GlobalSign Root CA - R3
validFrom long: epochmillis
1237370400000
validUntil long: epochmillis
1868522400000

VirtualThreadSubmitFailed

default profiling startTime duration 19 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/VirtualThreadSubmitFailedEvent.java

Category: Java Development Kit / Threading

Submit of task for virtual thread failed

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/VirtualThreadSubmitFailedEvent.java:

package jdk.internal.event;

/**
 * Event recording when an attempt to submit the task for a virtual thread failed.
 */
public class VirtualThreadSubmitFailedEvent extends Event {
    public long javaThreadId;
    public String exceptionMessage;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
        register("jdk.internal.event.FinalFieldMutationEvent", FinalFieldMutationEvent.class);
    };

    private static void register(String eventClassName, Class<? extends MirrorEvent> mirrorClass) {
        mirrorLookup.put(eventClassName, mirrorClass);
    }

src/jdk.jfr/share/classes/jdk/jfr/events/VirtualThreadSubmitFailedEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.MirrorEvent;
import jdk.jfr.internal.RemoveFields;

@Category({"Java Development Kit", "Threading"})
@Label("Virtual Thread Submit Failed")
@Name("jdk.VirtualThreadSubmitFailed")
@Description("Submit of task for virtual thread failed")
@RemoveFields("duration")
public final class VirtualThreadSubmitFailedEvent extends MirrorEvent {

    @Label("Thread Id")
    public long javaThreadId;

    @Label("Exception Message")
    public String exceptionMessage;

}

src/java.base/share/classes/java/lang/VirtualThread.java:

        if (scheduler == DEFAULT_SCHEDULER && currentCarrierThread() instanceof CarrierThread ct) {
            try {
                ct.getPool().externalSubmit(ForkJoinTask.adapt(runContinuation));
            } catch (RejectedExecutionException ree) {
                submitFailed(ree);
                throw ree;
            }
        } else {
            submitRunContinuation(scheduler, false);
        }
    }

    /**
     * If enabled, emits a JFR VirtualThreadSubmitFailedEvent.
     */
    private void submitFailed(RejectedExecutionException ree) {
        var event = new VirtualThreadSubmitFailedEvent();
        if (event.isEnabled()) {
            event.javaThreadId = threadId();
            event.exceptionMessage = ree.getMessage();
            event.commit();
        }
    }

    /**
     * Runs a task in the context of this virtual thread.
     */
    private void run(Runnable task) {

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default true true
profiling true true

Event fields with their types and descriptions
Field Type Description
javaThreadId long Thread Id
exceptionMessage string Exception Message

InitialSecurityProperty

default profiling startTime duration stackTrace 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/InitialSecurityPropertyEvent.java

Category: Java Development Kit / Security

Initial Security Properties

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        jdk.internal.event.SecurityProviderServiceEvent.class,
        jdk.internal.event.SerializationMisdeclarationEvent.class,
        jdk.internal.event.SocketReadEvent.class,
        jdk.internal.event.SocketWriteEvent.class,
        jdk.internal.event.ThreadSleepEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.VirtualThreadStartEvent.class,
        jdk.internal.event.VirtualThreadEndEvent.class,
        jdk.internal.event.VirtualThreadSubmitFailedEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,
        jdk.internal.event.FinalFieldMutationEvent.class,
        DirectBufferStatisticsEvent.class,
        InitialSecurityPropertyEvent.class,
        MethodTraceEvent.class,
        MethodTimingEvent.class,
    };

    private static final Runnable emitExceptionStatistics = JDKEvents::emitExceptionStatistics;
    private static final Runnable emitDirectBufferStatistics = JDKEvents::emitDirectBufferStatistics;
    private static final Runnable emitContainerConfiguration = JDKEvents::emitContainerConfiguration;
    private static final Runnable emitContainerCPUUsage = JDKEvents::emitContainerCPUUsage;
    private static final Runnable emitContainerCPUThrottling = JDKEvents::emitContainerCPUThrottling;
    private static final Runnable emitContainerMemoryUsage = JDKEvents::emitContainerMemoryUsage;
    private static final Runnable emitContainerIOUsage = JDKEvents::emitContainerIOUsage;

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

    private static final Runnable emitMethodTiming = JDKEvents::emitMethodTiming;
    private static Metrics containerMetrics = null;
    private static boolean initializationTriggered;

    @SuppressWarnings("unchecked")
    public static synchronized void initialize() {
        try {
            if (initializationTriggered == false) {
                for (Class<?> eventClass : eventClasses) {
                    MetadataRepository.getInstance().register((Class<? extends Event>) eventClass);
                }
                PeriodicEvents.addJavaEvent(jdk.internal.event.ExceptionStatisticsEvent.class, emitExceptionStatistics);
                PeriodicEvents.addJavaEvent(DirectBufferStatisticsEvent.class, emitDirectBufferStatistics);
                PeriodicEvents.addJavaEvent(InitialSecurityPropertyEvent.class, emitInitialSecurityProperties);
                PeriodicEvents.addJavaEvent(MethodTimingEvent.class, emitMethodTiming);

                initializeContainerEvents();
                JFRTracing.enable();
                initializationTriggered = true;
            }
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not initialize JDK events. " + e.getMessage());
        }
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        PeriodicEvents.removeEvent(emitContainerMemoryUsage);
        PeriodicEvents.removeEvent(emitContainerIOUsage);
    }

    private static void emitDirectBufferStatistics() {
        DirectBufferStatisticsEvent e = new DirectBufferStatisticsEvent();
        e.commit();
    }

    private static void emitInitialSecurityProperties() {
        Properties p = SharedSecrets.getJavaSecurityPropertiesAccess().getInitialProperties();
        if (p != null) {
            for (String key : p.stringPropertyNames()) {
                InitialSecurityPropertyEvent e = new InitialSecurityPropertyEvent();
                e.key = key;
                e.value = p.getProperty(key);
                e.commit();
            }
        }
    }

    private static void emitMethodTiming() {
        if (MethodSetting.isInitialized() && MethodTimingEvent.enabled()) {
            PlatformTracer.emitTiming();
        }

src/jdk.jfr/share/classes/jdk/jfr/events/InitialSecurityPropertyEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;

@Category({"Java Development Kit", "Security"})
@Label("Initial Security Property")
@Name("jdk.InitialSecurityProperty")
@Description("Initial Security Properties")
public final class InitialSecurityPropertyEvent extends AbstractPeriodicEvent {
    @Label("Key")
    public String key;

    @Label("Value")
    public String value;
}

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
key string Key
value string Value

Examples 3
Example event data values and properties
key string
securerandom.source
startTime long: millis
379421073
value string
file:/dev/random
Example event data values and properties
key string
ssl.KeyManagerFactory.algorithm
startTime long: millis
453272091628
value string
SunX509
Example event data values and properties
key string
com.sun.security.crl.maxSize
startTime long: millis
449656470757
value string
20971520

Operating System

OSInformation

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Operating System

Description of the OS the JVM runs on, for example, a uname-like output

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

TRACE_REQUEST_FUNC(ResidentSetSize) {
  os::jfr_report_memory_info();
}

TRACE_REQUEST_FUNC(JVMInformation) {
  JfrRedactedEvents::emit_jvm_information();
}

TRACE_REQUEST_FUNC(OSInformation) {
  ResourceMark rm;
  char* os_version = nullptr;
  JfrOSInterface::os_version(&os_version);
  EventOSInformation event;
  event.set_osVersion(os_version);
  event.commit();
}

TRACE_REQUEST_FUNC(VirtualizationInformation) {
  EventVirtualizationInformation event;
  event.set_name(JfrOSInterface::virtualization_name());
  event.commit();
}

TRACE_REQUEST_FUNC(ModuleRequire) {

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
osVersion string OS Version

Examples 3
Example event data values and properties
osVersion string
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=24.04 DISTRIB_CODENAME=noble DISTRIB_DESCRIPTION="Ubuntu 24.04.4 LTS" uname: Linux 6.17.0-1022-azure #22-Ubuntu SMP Mon Jul 27 17:24:03 UTC 2026 x86_64 libc: glibc 2.39 NPTL 2.39
startTime long: millis
479556524889
Example event data values and properties
osVersion string
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=24.04 DISTRIB_CODENAME=noble DISTRIB_DESCRIPTION="Ubuntu 24.04.4 LTS" uname: Linux 6.17.0-1022-azure #22-Ubuntu SMP Mon Jul 27 17:24:03 UTC 2026 x86_64 libc: glibc 2.39 NPTL 2.39
startTime long: millis
8024931989
Example event data values and properties
osVersion string
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=24.04 DISTRIB_CODENAME=noble DISTRIB_DESCRIPTION="Ubuntu 24.04.5 LTS" uname: Linux 6.17.0-1022-azure #22-Ubuntu SMP Mon Jul 27 17:24:03 UTC 2026 x86_64 libc: glibc 2.39 NPTL 2.39
startTime long: millis
462448393153

VirtualizationInformation

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Operating System

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Description of the virtualization technology the JVM runs on

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  JfrRedactedEvents::emit_jvm_information();
}

TRACE_REQUEST_FUNC(OSInformation) {
  ResourceMark rm;
  char* os_version = nullptr;
  JfrOSInterface::os_version(&os_version);
  EventOSInformation event;
  event.set_osVersion(os_version);
  event.commit();
}

TRACE_REQUEST_FUNC(VirtualizationInformation) {
  EventVirtualizationInformation event;
  event.set_name(JfrOSInterface::virtualization_name());
  event.commit();
}

TRACE_REQUEST_FUNC(ModuleRequire) {
  JfrModuleEvent::generate_module_dependency_events();
}

TRACE_REQUEST_FUNC(ModuleExport) {
  JfrModuleEvent::generate_module_export_events();
}

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
name string Name

Examples 3
Example event data values and properties
name string
Hyper-V virtualization
startTime long: millis
470826313263
Example event data values and properties
name string
Hyper-V virtualization
startTime long: millis
467163438560
Example event data values and properties
name string
Hyper-V virtualization
startTime long: millis
8024934183

InitialEnvironmentVariable

default profiling startTime end of every chunk 11 17 21 25 27 28

Category: Operating System

Key-value pairs for environment variables at JVM startup

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrRedactedEvents.cpp:

            _initial_environment_variables->append(new StringKeyValue(key, redacted_value->text()));
            delete redacted_value;
            continue;
          }
        }
        _initial_environment_variables->append(new StringKeyValue(key, value));
      }
    }
  }
  JfrTicks time_stamp = JfrTicks::now();
  for (int i = 0; i < _initial_environment_variables->length(); i++) {
    StringKeyValue* pair = _initial_environment_variables->at(i);
    EventInitialEnvironmentVariable event(UNTIMED);
    event.set_starttime(time_stamp);
    event.set_endtime(time_stamp);
    event.set_key(pair->key());
    event.set_value(pair->value());
    event.commit();
  }
  return true;
}

void JfrRedactedEvents::emit_initial_system_properties(bool log) {
  if (_initial_system_properties == nullptr) {

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
key string Key
value string Value

Examples 3
Example event data values and properties
key string
GITHUB_REPOSITORY
startTime long: millis
453049821122
value string
SAP/jfrevents
Example event data values and properties
key string
CHROMEWEBDRIVER
startTime long: millis
447754187781
value string
/usr/local/share/chromedriver-linux64
Example event data values and properties
key string
MEMORY_PRESSURE_WRITE
startTime long: millis
364524139
value string
c29tZSAyMDAwMDAgMjAwMDAwMAA=

SystemProcess

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Operating System

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  if (ret_val == OS_OK) {
    // feature is implemented, write real event
    while (processes != nullptr) {
      SystemProcess* tmp = processes;
      const char* info = processes->path();
      if (info == nullptr) {
         info = processes->name();
      }
      if (info == nullptr) {
         info = "?";
      }
      jio_snprintf(pid_buf, sizeof(pid_buf), "%d", processes->pid());
      EventSystemProcess event(UNTIMED);
      event.set_pid(pid_buf);
      event.set_commandLine(info);
      event.set_starttime(start_time);
      event.set_endtime(end_time);
      event.commit();
      processes = processes->next();
      delete tmp;
    }
  }
}

Event configuration settings across JFR profiles
Configuration enabled period
default true endChunk
profiling true endChunk

Event fields with their types and descriptions
Field Type Description
pid string Process Identifier
commandLine string Command Line

Examples 3
Example event data values and properties
commandLine string
php-fpm: pool www
pid string
1094
startTime long: millis
19479268756
Example event data values and properties
commandLine string
kworker/R-scsi_tmf_1
pid string
79
startTime long: millis
7826905875
Example event data values and properties
commandLine string
kworker/R-kmpathd
pid string
178
startTime long: millis
20528575745

CPUInformation

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Operating System / Processor

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Characteristics and descriptions of the processor(s) the JVM is running on

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

TRACE_REQUEST_FUNC(CPUInformation) {
  CPUInformation cpu_info;
  int ret_val = JfrOSInterface::cpu_information(cpu_info);
  if (ret_val == OS_ERR) {
    log_debug(jfr, system)( "Unable to generate requestable event CPUInformation");
    return;
  }
  if (ret_val == FUNCTIONALITY_NOT_IMPLEMENTED) {
     return;
  }
  if (ret_val == OS_OK) {
    EventCPUInformation event;
    event.set_cpu(cpu_info.cpu_name());
    event.set_description(cpu_info.cpu_description());
    event.set_sockets(cpu_info.number_of_sockets());
    event.set_cores(cpu_info.number_of_cores());
    event.set_hwThreads(cpu_info.number_of_hardware_threads());
    event.commit();
  }
}

TRACE_REQUEST_FUNC(CPULoad) {
  double u = 0; // user time

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
cpu string Type
description string Description
sockets uint Sockets
cores uint Cores Approximation on a hybrid CPU
hwThreads uint Hardware Threads

Examples 3
Example event data values and properties
cores uint
16
cpu string
AMD Unknown x86 (HT) SSE SSE2 SSE3 SSSE3 SSE4.1 SSE4.2 SSE4A AMD64
description string
Brand: AMD EPYC 7763 64-Core Processor , Vendor: AuthenticAMD Family: Unknown x86 (0x19), Model: <unknown> (0x1), Stepping: 0x1 Ext. family: 0xa, Ext. model: 0x0, Type: 0x0, Signature: 0x00a00f11 Features: ebx: 0x02100800, ecx: 0xfeda3203, edx: 0x178bfbff Ext. features: eax: 0x00a00f1…
hwThreads uint
4
sockets uint
1
startTime long: millis
493399334249
Example event data values and properties
cores uint
16
cpu string
AMD Unknown x86 (HT) SSE SSE2 SSE3 SSSE3 SSE4.1 SSE4.2 SSE4A AMD64
description string
Brand: AMD EPYC 7763 64-Core Processor , Vendor: AuthenticAMD Family: Unknown x86 (0x19), Model: <unknown> (0x1), Stepping: 0x1 Ext. family: 0xa, Ext. model: 0x0, Type: 0x0, Signature: 0x00a00f11 Features: ebx: 0x01100800, ecx: 0xfeda3203, edx: 0x178bfbff Ext. features: eax: 0x00a00f1…
hwThreads uint
4
sockets uint
1
startTime long: millis
364564385
Example event data values and properties
cores uint
16
cpu string
AMD Unknown x86 (HT) SSE SSE2 SSE3 SSSE3 SSE4.1 SSE4.2 SSE4A AMD64
description string
Brand: AMD EPYC 9V74 80-Core Processor , Vendor: AuthenticAMD Family: Unknown x86 (0x19), Model: <unknown> (0x11), Stepping: 0x1 Ext. family: 0xa, Ext. model: 0x1, Type: 0x0, Signature: 0x00a10f11 Features: ebx: 0x02100800, ecx: 0xfeda3203, edx: 0x178bfbff Ext. features: eax: 0x00a10f…
hwThreads uint
4
sockets uint
1
startTime long: millis
451440080748

CPUTimeStampCounter

default profiling startTime duration end of every chunk 11 17 21 25 27 28

Category: Operating System / Processor

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Information about the CPU time stamp mechanism / (RD)TSC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

TRACE_REQUEST_FUNC(ThreadCPULoad) {
  JfrThreadCPULoadEvent::send_events();
}

TRACE_REQUEST_FUNC(CompilerQueueUtilization) {
  JfrCompilerQueueUtilization::send_events();
}

TRACE_REQUEST_FUNC(NetworkUtilization) {
  JfrNetworkUtilization::send_events();
}

TRACE_REQUEST_FUNC(CPUTimeStampCounter) {
  EventCPUTimeStampCounter event;
  event.set_fastTimeEnabled(JfrTime::is_ft_enabled());
  event.set_fastTimeAutoEnabled(JfrTime::is_ft_supported());
  event.set_osFrequency(os::elapsed_frequency());
  event.set_fastTimeFrequency(JfrTime::frequency());
  event.commit();
}

TRACE_REQUEST_FUNC(SystemProcess) {
  char pid_buf[16];
  SystemProcess* processes = nullptr;
  int num_of_processes = 0;

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
fastTimeEnabled boolean Fast Time
fastTimeAutoEnabled boolean Trusted Platform
osFrequency long: hertz OS Frequency
fastTimeFrequency long: hertz Fast Time Frequency

Examples 3
Example event data values and properties
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
454119505600
Example event data values and properties
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
364567681
Example event data values and properties
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
467163461684

CPULoad

default profiling startTime duration every chunk 11 17 21 25 27 28

Category: Operating System / Processor

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Information about the recent CPU usage of the JVM process

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  double t = 0; // total time
  int ret_val = OS_ERR;
  {
    // Can take some time on certain platforms, especially under heavy load.
    // Transition to native to avoid unnecessary stalls for pending safepoint synchronizations.
    ThreadToNativeFromVM transition(JavaThread::current());
    ret_val = JfrOSInterface::cpu_loads_process(&u, &s, &t);
  }
  if (ret_val == OS_ERR) {
    log_debug(jfr, system)( "Unable to generate requestable event CPULoad");
    return;
  }
  if (ret_val == OS_OK) {
    EventCPULoad event;
    event.set_jvmUser((float)u);
    event.set_jvmSystem((float)s);
    event.set_machineTotal((float)t);
    event.commit();
  }
}

TRACE_REQUEST_FUNC(ThreadCPULoad) {
  JfrThreadCPULoadEvent::send_events();
}

Event configuration settings across JFR profiles
Configuration enabled period
default true 1000 ms
profiling true 1000 ms

Event fields with their types and descriptions
Field Type Description
jvmUser float: percentage JVM User
jvmSystem float: percentage JVM System
machineTotal float: percentage Machine Total

Examples 3
Example event data values and properties
jvmSystem float: percentage
0.0
jvmUser float: percentage
0.265
machineTotal float: percentage
0.265
startTime long: millis
484857097105
Example event data values and properties
jvmSystem float: percentage
0.10723192
jvmUser float: percentage
0.46882793
machineTotal float: percentage
0.5785536
startTime long: millis
491165624204
Example event data values and properties
jvmSystem float: percentage
0.017902814
jvmUser float: percentage
0.3375959
machineTotal float: percentage
0.35549873
startTime long: millis
22876827195

ThreadCPULoad

default profiling startTime duration eventThread every chunk 11 17 21 25 27 28

Category: Operating System / Processor

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrThreadCPULoadEvent.cpp:

int JfrThreadCPULoadEvent::get_processor_count() {
  int cur_processor_count = os::active_processor_count();
  int last_processor_count = _last_active_processor_count;
  _last_active_processor_count = cur_processor_count;

  // If the number of processors decreases, we don't know at what point during
  // the sample interval this happened, so use the largest number to try
  // to avoid percentages above 100%
  return MAX2(cur_processor_count, last_processor_count);
}

// Returns false if the thread has not been scheduled since the last call to updateEvent
// (i.e. the delta for both system and user time is 0 milliseconds)
bool JfrThreadCPULoadEvent::update_event(EventThreadCPULoad& event, JavaThread* thread, jlong cur_wallclock_time, int processor_count) {
  JfrThreadLocal* const tl = thread->jfr_thread_local();

  jlong cur_cpu_time = os::thread_cpu_time(thread, true);
  jlong prev_cpu_time = tl->get_cpu_time();

  jlong prev_wallclock_time = tl->get_wallclock_time();
  tl->set_wallclock_time(cur_wallclock_time);

  // Threshold of 1 ms
  if (cur_cpu_time - prev_cpu_time < 1 * NANOSECS_PER_MILLISEC) {
    return false;

src/hotspot/share/jfr/periodic/jfrThreadCPULoadEvent.cpp:

void JfrThreadCPULoadEvent::send_events() {
  Thread* periodic_thread = Thread::current();
  traceid periodic_thread_id = JfrThreadLocal::thread_id(periodic_thread);
  const int processor_count = JfrThreadCPULoadEvent::get_processor_count();
  JfrTicks event_time = JfrTicks::now();
  jlong cur_wallclock_time = JfrThreadCPULoadEvent::get_wallclock_time();

  JfrJavaThreadIterator iter;
  int number_of_threads = 0;
  while (iter.has_next()) {
    JavaThread* const jt = iter.next();
    assert(jt != nullptr, "invariant");
    ++number_of_threads;
    EventThreadCPULoad event(UNTIMED);
    if (JfrThreadCPULoadEvent::update_event(event, jt, cur_wallclock_time, processor_count)) {
      event.set_starttime(event_time);
      event.set_endtime(event_time);
      if (jt != periodic_thread) {
        // Commit reads the thread id from this thread's trace data, so put it there temporarily
        JfrThreadLocal::impersonate(periodic_thread, JFR_JVM_THREAD_ID(jt));
      } else {
        JfrThreadLocal::impersonate(periodic_thread, periodic_thread_id);
      }
      event.commit();
    }
  }
  log_trace(jfr)("Measured CPU usage for %d threads in %.3f milliseconds", number_of_threads,
    (double)(JfrTicks::now() - event_time).milliseconds());
  JfrThreadLocal::stop_impersonating(periodic_thread);
}

void JfrThreadCPULoadEvent::send_event_for_thread(JavaThread* jt) {
  EventThreadCPULoad event;
  if (event.should_commit()) {
    if (update_event(event, jt, get_wallclock_time(), get_processor_count())) {
      event.commit();
    }
  }
}

src/hotspot/share/jfr/periodic/jfrThreadCPULoadEvent.hpp:

#ifndef SHARE_JFR_PERIODIC_JFRTHREADCPULOADEVENT_HPP
#define SHARE_JFR_PERIODIC_JFRTHREADCPULOADEVENT_HPP

#include "jni.h"
#include "memory/allStatic.hpp"

class JavaThread;
class EventThreadCPULoad;

class JfrThreadCPULoadEvent : public AllStatic {
  static int _last_active_processor_count;
 public:
  static jlong get_wallclock_time();
  static int get_processor_count();
  static bool update_event(EventThreadCPULoad& event, JavaThread* thread, jlong cur_wallclock_time, int processor_count);
  static void send_events();
  static void send_event_for_thread(JavaThread* jt);
};

#endif // SHARE_JFR_PERIODIC_JFRTHREADCPULOADEVENT_HPP

Event configuration settings across JFR profiles
Configuration enabled period
default true 10 s
profiling true 10 s

Event fields with their types and descriptions
Field Type Description
user float: percentage User Mode CPU Load User mode thread CPU load
system float: percentage System Mode CPU Load System mode thread CPU load

Examples 3
Example event data values and properties
startTime long: millis
461269819977
system float: percentage
2.54129E-5
user float: percentage
0.0
Example event data values and properties
startTime long: millis
455798353258
system float: percentage
2.9331992E-5
user float: percentage
0.0
Example event data values and properties
startTime long: millis
24656856919
system float: percentage
0.20180139
user float: percentage
0.0

ThreadContextSwitchRate

default profiling startTime duration every chunk 11 17 21 25 27 28

Category: Operating System / Processor

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

    // Can take some time on certain platforms, especially under heavy load.
    // Transition to native to avoid unnecessary stalls for pending safepoint synchronizations.
    ThreadToNativeFromVM transition(JavaThread::current());
    ret_val = JfrOSInterface::context_switch_rate(&rate);
  }
  if (ret_val == OS_ERR) {
    log_debug(jfr, system)( "Unable to generate requestable event ThreadContextSwitchRate");
    return;
  }
  if (ret_val == FUNCTIONALITY_NOT_IMPLEMENTED) {
    return;
  }
  if (ret_val == OS_OK) {
    EventThreadContextSwitchRate event;
    event.set_switchRate((float)rate + 0.0f);
    event.commit();
  }
}

#define SEND_FLAGS_OF_TYPE(eventType, flagType)                   \
  do {                                                            \
    JVMFlag *flag = JVMFlag::flags;                               \
    while (flag->name() != nullptr) {                             \
      if (flag->is_ ## flagType()) {                              \
        if (flag->is_unlocked()) {                                \

Event configuration settings across JFR profiles
Configuration enabled period
default true 10 s
profiling true 10 s

Event fields with their types and descriptions
Field Type Description
switchRate float: hertz Switch Rate Number of context switches per second

Examples 3
Example event data values and properties
startTime long: millis
495798945486
switchRate float: hertz
5066.3643
Example event data values and properties
startTime long: millis
487918475002
switchRate float: hertz
3825.5344
Example event data values and properties
startTime long: millis
10584510779
switchRate float: hertz
9365.798

NetworkUtilization

default profiling startTime every chunk 11 17 21 25 27 28

Category: Operating System / Network

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrNetworkUtilization.cpp:

  static JfrTicks last_sample_instant;
  const JfrTicks cur_time = JfrTicks::now();
  if (cur_time > last_sample_instant) {
    const JfrTickspan interval = cur_time - last_sample_instant;
    for (NetworkInterface *cur = network_interfaces; cur != nullptr; cur = cur->next()) {
      InterfaceEntry& entry = get_entry(cur);
      const uint64_t current_bytes_in = cur->get_bytes_in();
      const uint64_t current_bytes_out = cur->get_bytes_out();
      const uint64_t read_rate = rate_per_second(current_bytes_in, entry.bytes_in, interval);
      const uint64_t write_rate = rate_per_second(current_bytes_out, entry.bytes_out, interval);
      if (read_rate > 0 || write_rate > 0) {
        write_interface_constant(entry);
        EventNetworkUtilization event(UNTIMED);
        event.set_starttime(cur_time);
        event.set_endtime(cur_time);
        event.set_networkInterface(entry.id);
        event.set_readRate(8 * read_rate);
        event.set_writeRate(8 * write_rate);
        event.commit();
      }
      // update existing entry with new values
      entry.bytes_in = current_bytes_in;
      entry.bytes_out = current_bytes_out;
    }

Event configuration settings across JFR profiles
Configuration enabled period
default true 5 s
profiling true 5 s

Event fields with their types and descriptions
Field Type Description
networkInterface NetworkInterfaceName Network Interface Network Interface Name
readRate long: bits-per-second Read Rate Number of incoming bits per second
writeRate long: bits-per-second Write Rate Number of outgoing bits per second

Examples 3
Example event data values and properties
networkInterface NetworkInterfaceName
eth0
readRate long: bits-per-second
17544
startTime long: millis
10584053020
writeRate long: bits-per-second
13136
Example event data values and properties
networkInterface NetworkInterfaceName
enP24070s1
readRate long: bits-per-second
4192
startTime long: millis
484104974762
writeRate long: bits-per-second
5568
Example event data values and properties
networkInterface NetworkInterfaceName
lo
readRate long: bits-per-second
7685840
startTime long: millis
509366896707
writeRate long: bits-per-second
7685840

PhysicalMemory

default profiling startTime duration every chunk 11 17 21 25 27 28

Category: Operating System / Memory

OS Physical Memory

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

 *  PhysicalMemory event represents:
 *
 *  @totalSize == The amount of physical memory (hw) installed and reported by the OS, in bytes.
 *  @usedSize  == The amount of physical memory currently in use in the system (reserved/committed), in bytes.
 *
 *  Both fields are systemwide, i.e. represents the entire OS/HW environment.
 *  These fields do not include virtual memory.
 *
 *  If running inside a guest OS on top of a hypervisor in a virtualized environment,
 *  the total memory reported is the amount of memory configured for the guest OS by the hypervisor.
 */
TRACE_REQUEST_FUNC(PhysicalMemory) {
  physical_memory_size_type totalPhysicalMemory = os::physical_memory();
  EventPhysicalMemory event;
  event.set_totalSize(totalPhysicalMemory);
  physical_memory_size_type avail_mem = 0;
  // Return value ignored - defaulting to 0 on failure.
  (void)os::available_memory(avail_mem);
  event.set_usedSize(totalPhysicalMemory - avail_mem);
  event.commit();
}

TRACE_REQUEST_FUNC(SwapSpace) {
  EventSwapSpace event;
  physical_memory_size_type total_swap_space = 0;

Event configuration settings across JFR profiles
Configuration enabled period
default true everyChunk
profiling true everyChunk

Event fields with their types and descriptions
Field Type Description
totalSize ulong: bytes Total Size Total amount of physical memory available to OS
usedSize ulong: bytes Used Size Total amount of physical memory in use

Examples 3
Example event data values and properties
startTime long: millis
449445077314
totalSize ulong: bytes
16766414848
usedSize ulong: bytes
7022059520
Example event data values and properties
startTime long: millis
479556592846
totalSize ulong: bytes
16766414848
usedSize ulong: bytes
4181684224
Example event data values and properties
startTime long: millis
8024973347
totalSize ulong: bytes
16766414848
usedSize ulong: bytes
1226985472

SwapSpace

default profiling startTime duration every chunk 23 25 27 28

Category: Operating System / Memory

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

OS Swap Space

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

 */
TRACE_REQUEST_FUNC(PhysicalMemory) {
  physical_memory_size_type totalPhysicalMemory = os::physical_memory();
  EventPhysicalMemory event;
  event.set_totalSize(totalPhysicalMemory);
  physical_memory_size_type avail_mem = 0;
  // Return value ignored - defaulting to 0 on failure.
  (void)os::available_memory(avail_mem);
  event.set_usedSize(totalPhysicalMemory - avail_mem);
  event.commit();
}

TRACE_REQUEST_FUNC(SwapSpace) {
  EventSwapSpace event;
  physical_memory_size_type total_swap_space = 0;
  // Return value ignored - defaulting to 0 on failure.
  (void)os::total_swap_space(total_swap_space);
  event.set_totalSize(static_cast<s8>(total_swap_space));
  physical_memory_size_type free_swap_space = 0;
  // Return value ignored - defaulting to 0 on failure.
  (void)os::free_swap_space(free_swap_space);
  event.set_freeSize(static_cast<s8>(free_swap_space));
  event.commit();
}

Event configuration settings across JFR profiles
Configuration enabled period
default true everyChunk
profiling true everyChunk

Event fields with their types and descriptions
Field Type Description
totalSize long: bytes Total Size Total swap space available to the OS
freeSize long: bytes Free Size Free swap space

Examples 3
Example event data values and properties
freeSize long: bytes
3221221376
startTime long: millis
487374109588
totalSize long: bytes
3221221376
Example event data values and properties
freeSize long: bytes
3221221376
startTime long: millis
7832168891
totalSize long: bytes
3221221376
Example event data values and properties
freeSize long: bytes
3221221376
startTime long: millis
477043539384
totalSize long: bytes
3221221376

ProcessStart

default profiling startTime duration 15 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/ProcessStartEvent.java

Category: Operating System

Excludes in stack trace: java.lang.ProcessBuilder, java.lang.Runtime::exec

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Operating system process started

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/ProcessStartEvent.java:

package jdk.internal.event;

/**
 * Event for the start of an OS procsss
 */

public final class ProcessStartEvent extends Event {
    public long pid;
    public String directory;
    public String command;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

/**
 * This class registers all mirror events.
 */
final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);

src/jdk.jfr/share/classes/jdk/jfr/events/ProcessStartEvent.java:

@Category({"Operating System"})
@Label("Process Start")
@Name("jdk.ProcessStart")
@Description("Operating system process started")
@RemoveFields("duration")
@StackFilter({"java.lang.ProcessBuilder", "java.lang.Runtime::exec"})
public final class ProcessStartEvent extends MirrorEvent {
    @Label("Process Id")
    public long pid;

    @Label("Directory")
    public String directory;

    @Label("Command")
    public String command;
}

src/java.base/share/classes/java/lang/ProcessBuilder.java:

        for (String s : cmdarray) {
            if (s.indexOf('\u0000') >= 0) {
                throw new IOException("invalid null character in command");
            }
        }

        try {
            Process process = ProcessImpl.start(cmdarray,
                                     environment,
                                     dir,
                                     redirects,
                                     redirectErrorStream);
            ProcessStartEvent event = new ProcessStartEvent();
            if (event.isEnabled()) {
                event.directory = dir;
                event.command = String.join(" ", cmdarray);
                event.pid = process.pid();
                event.commit();
            }
            // Racy initialization for logging; errors in configuration may throw exceptions
            System.Logger logger = LOGGER;
            if (logger == null) {
                LOGGER = logger = System.getLogger("java.lang.ProcessBuilder");
            }

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default true true
profiling true true

Event fields with their types and descriptions
Field Type Description
pid long Process Id
directory string Directory
command string Command

Examples 3
Example event data values and properties
command string
rm -rf /home/runner/work/jfrevents/jfrevents/harness-002552-11024252767585181307/apache-spark/gauss-mix/blockmgr-f7c75636-1699-4af0-941d-65cec3940163
directory string
null
pid long
4462
startTime long: millis
475245775886
Example event data values and properties
command string
rm -rf /home/runner/work/jfrevents/jfrevents/harness-124410-7892773325794487906/apache-spark/gauss-mix/blockmgr-1d14a293-a670-4b80-9780-9c2d77740aa6
directory string
null
pid long
4876
startTime long: millis
480360647728
Example event data values and properties
command string
java -version
directory string
null
pid long
5056
startTime long: millis
1147234961

ContainerCPUThrottling

default profiling startTime duration stackTrace 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/ContainerCPUThrottlingEvent.java

Category: Operating System / Processor

Container CPU throttling related information

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

    private static void initializeContainerEvents() {
        if (JVM.isContainerized() ) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "JVM is containerized");
            containerMetrics = Container.metrics();
            if (containerMetrics != null) {
                Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "Container metrics are available");
            }
        }
        // The registration of events and hooks are needed to provide metadata,
        // even when not running in a container
        registerEvent(ContainerConfigurationEvent.class);
        registerEvent(ContainerCPUUsageEvent.class);
        registerEvent(ContainerCPUThrottlingEvent.class);
        registerEvent(ContainerMemoryUsageEvent.class);
        registerEvent(ContainerIOUsageEvent.class);

        PeriodicEvents.addJavaEvent(ContainerConfigurationEvent.class, emitContainerConfiguration);
        PeriodicEvents.addJavaEvent(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        PeriodicEvents.addJavaEvent(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        PeriodicEvents.addJavaEvent(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        PeriodicEvents.addJavaEvent(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void registerEvent(Class<? extends jdk.internal.event.Event> eventClass) {
        MetadataRepository.getInstance().register(eventClass);
    }

    private static void emitExceptionStatistics() {
        ThrowableTracer.emitStatistics();
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

    private static void emitContainerIOUsage() {
        if (containerMetrics != null) {
            ContainerIOUsageEvent event = new ContainerIOUsageEvent();

            event.serviceRequests = containerMetrics.getBlkIOServiceCount();
            event.dataTransferred = containerMetrics.getBlkIOServiced();
            event.commit();
        }
    }

    private static void emitContainerCPUThrottling() {
        if (containerMetrics != null) {
            ContainerCPUThrottlingEvent event = new ContainerCPUThrottlingEvent();

            event.cpuElapsedSlices = containerMetrics.getCpuNumPeriods();
            event.cpuThrottledSlices = containerMetrics.getCpuNumThrottled();
            event.cpuThrottledTime = containerMetrics.getCpuThrottledTime();
            event.commit();
        }
    }

    public static void remove() {
        PeriodicEvents.removeEvent(emitExceptionStatistics);
        PeriodicEvents.removeEvent(emitDirectBufferStatistics);

src/jdk.jfr/share/classes/jdk/jfr/events/ContainerCPUThrottlingEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.Timespan;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "ContainerCPUThrottling")
@Label("CPU Throttling")
@Category({"Operating System", "Processor"})
@Description("Container CPU throttling related information")
public class ContainerCPUThrottlingEvent extends AbstractPeriodicEvent {
  @Label("CPU Elapsed Slices")
  @Description("Number of time-slice periods that have elapsed if a CPU quota has been setup for the container")
  public long cpuElapsedSlices;

  @Label("CPU Throttled Slices")
  @Description("Number of time-slice periods that the CPU has been throttled or limited due to exceeding CPU quota")
  public long cpuThrottledSlices;

  @Label("CPU Throttled Time")
  @Description("Total time duration, in nanoseconds, that the CPU has been throttled or limited due to exceeding CPU quota")
  @Timespan

Event configuration settings across JFR profiles
Configuration enabled period
default true 30 s
profiling true 30 s

Event fields with their types and descriptions
Field Type Description
cpuElapsedSlices long CPU Elapsed Slices Number of time-slice periods that have elapsed if a CPU quota has been setup for the container
cpuThrottledSlices long CPU Throttled Slices Number of time-slice periods that the CPU has been throttled or limited due to exceeding CPU quota
cpuThrottledTime long: nanos CPU Throttled Time Total time duration, in nanoseconds, that the CPU has been throttled or limited due to exceeding CPU quota

ContainerCPUUsage

default profiling startTime duration stackTrace 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/ContainerCPUUsageEvent.java

Category: Operating System / Processor

Container CPU usage related information

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

    private static void initializeContainerEvents() {
        if (JVM.isContainerized() ) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "JVM is containerized");
            containerMetrics = Container.metrics();
            if (containerMetrics != null) {
                Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "Container metrics are available");
            }
        }
        // The registration of events and hooks are needed to provide metadata,
        // even when not running in a container
        registerEvent(ContainerConfigurationEvent.class);
        registerEvent(ContainerCPUUsageEvent.class);
        registerEvent(ContainerCPUThrottlingEvent.class);
        registerEvent(ContainerMemoryUsageEvent.class);
        registerEvent(ContainerIOUsageEvent.class);

        PeriodicEvents.addJavaEvent(ContainerConfigurationEvent.class, emitContainerConfiguration);
        PeriodicEvents.addJavaEvent(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        PeriodicEvents.addJavaEvent(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        PeriodicEvents.addJavaEvent(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        PeriodicEvents.addJavaEvent(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void registerEvent(Class<? extends jdk.internal.event.Event> eventClass) {
        MetadataRepository.getInstance().register(eventClass);
    }

    private static void emitExceptionStatistics() {
        ThrowableTracer.emitStatistics();

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

            t.cpuShares = containerMetrics.getCpuShares();
            t.effectiveCpuCount = containerMetrics.getEffectiveCpuCount();
            t.memorySoftLimit = containerMetrics.getMemorySoftLimit();
            t.memoryLimit = containerMetrics.getMemoryLimit();
            t.swapMemoryLimit = containerMetrics.getMemoryAndSwapLimit();
            t.hostTotalMemory = JVM.hostTotalMemory();
            t.hostTotalSwapMemory = JVM.hostTotalSwapMemory();
            t.commit();
        }
    }

    private static void emitContainerCPUUsage() {
        if (containerMetrics != null) {
            ContainerCPUUsageEvent event = new ContainerCPUUsageEvent();

            event.cpuTime = containerMetrics.getCpuUsage();
            event.cpuSystemTime = containerMetrics.getCpuSystemUsage();
            event.cpuUserTime = containerMetrics.getCpuUserUsage();
            event.commit();
        }
    }
    private static void emitContainerMemoryUsage() {
        if (containerMetrics != null) {
            ContainerMemoryUsageEvent event = new ContainerMemoryUsageEvent();

src/jdk.jfr/share/classes/jdk/jfr/events/ContainerCPUUsageEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.Timespan;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "ContainerCPUUsage")
@Label("CPU Usage")
@Category({"Operating System", "Processor"})
@Description("Container CPU usage related information")
public class ContainerCPUUsageEvent extends AbstractPeriodicEvent {
  @Label("CPU Time")
  @Description("Aggregate time consumed by all tasks in the container")
  @Timespan
  public long cpuTime;

  @Label("CPU User Time")
  @Description("Aggregate user time consumed by all tasks in the container")
  @Timespan
  public long cpuUserTime;

  @Label("CPU System Time")

Event configuration settings across JFR profiles
Configuration enabled period
default true 30 s
profiling true 30 s

Event fields with their types and descriptions
Field Type Description
cpuTime long: nanos CPU Time Aggregate time consumed by all tasks in the container
cpuUserTime long: nanos CPU User Time Aggregate user time consumed by all tasks in the container
cpuSystemTime long: nanos CPU System Time Aggregate system time consumed by all tasks in the container

ContainerMemoryUsage

default profiling startTime duration stackTrace 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/ContainerMemoryUsageEvent.java

Category: Operating System / Memory

Container memory usage related information

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

    private static void initializeContainerEvents() {
        if (JVM.isContainerized() ) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "JVM is containerized");
            containerMetrics = Container.metrics();
            if (containerMetrics != null) {
                Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "Container metrics are available");
            }
        }
        // The registration of events and hooks are needed to provide metadata,
        // even when not running in a container
        registerEvent(ContainerConfigurationEvent.class);
        registerEvent(ContainerCPUUsageEvent.class);
        registerEvent(ContainerCPUThrottlingEvent.class);
        registerEvent(ContainerMemoryUsageEvent.class);
        registerEvent(ContainerIOUsageEvent.class);

        PeriodicEvents.addJavaEvent(ContainerConfigurationEvent.class, emitContainerConfiguration);
        PeriodicEvents.addJavaEvent(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        PeriodicEvents.addJavaEvent(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        PeriodicEvents.addJavaEvent(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        PeriodicEvents.addJavaEvent(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void registerEvent(Class<? extends jdk.internal.event.Event> eventClass) {
        MetadataRepository.getInstance().register(eventClass);
    }

    private static void emitExceptionStatistics() {
        ThrowableTracer.emitStatistics();
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

    private static void emitContainerCPUUsage() {
        if (containerMetrics != null) {
            ContainerCPUUsageEvent event = new ContainerCPUUsageEvent();

            event.cpuTime = containerMetrics.getCpuUsage();
            event.cpuSystemTime = containerMetrics.getCpuSystemUsage();
            event.cpuUserTime = containerMetrics.getCpuUserUsage();
            event.commit();
        }
    }
    private static void emitContainerMemoryUsage() {
        if (containerMetrics != null) {
            ContainerMemoryUsageEvent event = new ContainerMemoryUsageEvent();

            event.memoryFailCount = containerMetrics.getMemoryFailCount();
            event.memoryUsage = containerMetrics.getMemoryUsage();
            event.swapMemoryUsage = containerMetrics.getMemoryAndSwapUsage();
            event.hostMemoryUsage = JVM.hostMemoryUsage();
            event.commit();
        }
    }

    private static void emitContainerIOUsage() {
        if (containerMetrics != null) {

src/jdk.jfr/share/classes/jdk/jfr/events/ContainerMemoryUsageEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.DataAmount;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "ContainerMemoryUsage")
@Label("Container Memory Usage")
@Category({"Operating System", "Memory"})
@Description("Container memory usage related information")
public final class ContainerMemoryUsageEvent extends AbstractPeriodicEvent {
    @Label("Memory Fail Count")
    @Description("Number of times that user memory requests in the container have exceeded the memory limit")
    public long memoryFailCount;

    @Label("Memory Usage")
    @Description("Amount of physical memory, in bytes, that is currently allocated in the current container")
    @DataAmount
    public long memoryUsage;

    @Label("Memory and Swap Usage")
    @Description("Amount of physical memory and swap space, in bytes, that is currently allocated in the current container")

Event configuration settings across JFR profiles
Configuration enabled period
default true 30 s
profiling true 30 s

Event fields with their types and descriptions
Field Type Description
memoryFailCount long Memory Fail Count Number of times that user memory requests in the container have exceeded the memory limit
memoryUsage long: bytes Memory Usage Amount of physical memory, in bytes, that is currently allocated in the current container
swapMemoryUsage long: bytes Memory and Swap Usage Amount of physical memory and swap space, in bytes, that is currently allocated in the current container
hostMemoryUsage long: bytes 27+ Host Memory Usage Amount of physical memory, in bytes, that is currently allocated in the host system

ContainerConfiguration

default profiling startTime duration stackTrace 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/ContainerConfigurationEvent.java

Category: Operating System

A set of container specific attributes

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

    private static void initializeContainerEvents() {
        if (JVM.isContainerized() ) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "JVM is containerized");
            containerMetrics = Container.metrics();
            if (containerMetrics != null) {
                Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "Container metrics are available");
            }
        }
        // The registration of events and hooks are needed to provide metadata,
        // even when not running in a container
        registerEvent(ContainerConfigurationEvent.class);
        registerEvent(ContainerCPUUsageEvent.class);
        registerEvent(ContainerCPUThrottlingEvent.class);
        registerEvent(ContainerMemoryUsageEvent.class);
        registerEvent(ContainerIOUsageEvent.class);

        PeriodicEvents.addJavaEvent(ContainerConfigurationEvent.class, emitContainerConfiguration);
        PeriodicEvents.addJavaEvent(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        PeriodicEvents.addJavaEvent(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        PeriodicEvents.addJavaEvent(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        PeriodicEvents.addJavaEvent(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void registerEvent(Class<? extends jdk.internal.event.Event> eventClass) {
        MetadataRepository.getInstance().register(eventClass);
    }

    private static void emitExceptionStatistics() {
        ThrowableTracer.emitStatistics();
    }

    private static void emitContainerConfiguration() {
        if (containerMetrics != null) {
            ContainerConfigurationEvent t = new ContainerConfigurationEvent();
            t.containerType = containerMetrics.getProvider();
            t.cpuSlicePeriod = containerMetrics.getCpuPeriod();
            t.cpuQuota = containerMetrics.getCpuQuota();
            t.cpuShares = containerMetrics.getCpuShares();
            t.effectiveCpuCount = containerMetrics.getEffectiveCpuCount();
            t.memorySoftLimit = containerMetrics.getMemorySoftLimit();
            t.memoryLimit = containerMetrics.getMemoryLimit();
            t.swapMemoryLimit = containerMetrics.getMemoryAndSwapLimit();
            t.hostTotalMemory = JVM.hostTotalMemory();
            t.hostTotalSwapMemory = JVM.hostTotalSwapMemory();
            t.commit();

src/jdk.jfr/share/classes/jdk/jfr/events/ContainerConfigurationEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "ContainerConfiguration")
@Label("Container Configuration")
@Category({"Operating System"})
@Description("A set of container specific attributes")
public final class ContainerConfigurationEvent extends AbstractPeriodicEvent {
    @Label("Container Type")
    @Description("Container type information")
    public String containerType;

    @Label("CPU Slice Period")
    @Description("Length of the scheduling period for processes within the container")
    @Timespan(Timespan.MICROSECONDS)
    public long cpuSlicePeriod;

    @Label("CPU Quota")
    @Description("Total available run-time allowed during each scheduling period for all tasks in the container")

Event configuration settings across JFR profiles
Configuration enabled period
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
containerType string Container Type Container type information
cpuSlicePeriod long: microseconds CPU Slice Period Length of the scheduling period for processes within the container
cpuQuota long: microseconds CPU Quota Total available run-time allowed during each scheduling period for all tasks in the container
cpuShares long CPU Shares Relative weighting of processes with the container used for prioritizing the scheduling of processes across all containers running on a host
effectiveCpuCount long Effective CPU Count Number of effective processors that this container has available to it
memorySoftLimit long: bytes Memory Soft Limit Hint to the operating system that allows groups to specify the minimum required amount of physical memory
memoryLimit long: bytes Memory Limit Maximum amount of physical memory that can be allocated in the container
swapMemoryLimit long: bytes Memory and Swap Limit Maximum amount of physical memory and swap space, in bytes, that can be allocated in the container
hostTotalMemory long: bytes 20+ Container Host Total Memory Total memory of the host running the container
hostTotalSwapMemory long: bytes 23+ Container Host Total Swap Memory Total swap memory of the host running the container

ContainerIOUsage

default profiling startTime duration stackTrace 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/ContainerIOUsageEvent.java

Category: Operating System / File System

Container IO usage related information

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        if (JVM.isContainerized() ) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "JVM is containerized");
            containerMetrics = Container.metrics();
            if (containerMetrics != null) {
                Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "Container metrics are available");
            }
        }
        // The registration of events and hooks are needed to provide metadata,
        // even when not running in a container
        registerEvent(ContainerConfigurationEvent.class);
        registerEvent(ContainerCPUUsageEvent.class);
        registerEvent(ContainerCPUThrottlingEvent.class);
        registerEvent(ContainerMemoryUsageEvent.class);
        registerEvent(ContainerIOUsageEvent.class);

        PeriodicEvents.addJavaEvent(ContainerConfigurationEvent.class, emitContainerConfiguration);
        PeriodicEvents.addJavaEvent(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        PeriodicEvents.addJavaEvent(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        PeriodicEvents.addJavaEvent(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        PeriodicEvents.addJavaEvent(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void registerEvent(Class<? extends jdk.internal.event.Event> eventClass) {
        MetadataRepository.getInstance().register(eventClass);
    }

    private static void emitExceptionStatistics() {
        ThrowableTracer.emitStatistics();
    }

    private static void emitContainerConfiguration() {

src/jdk.jfr/share/classes/jdk/jfr/internal/JDKEvents.java:

        if (containerMetrics != null) {
            ContainerMemoryUsageEvent event = new ContainerMemoryUsageEvent();

            event.memoryFailCount = containerMetrics.getMemoryFailCount();
            event.memoryUsage = containerMetrics.getMemoryUsage();
            event.swapMemoryUsage = containerMetrics.getMemoryAndSwapUsage();
            event.hostMemoryUsage = JVM.hostMemoryUsage();
            event.commit();
        }
    }

    private static void emitContainerIOUsage() {
        if (containerMetrics != null) {
            ContainerIOUsageEvent event = new ContainerIOUsageEvent();

            event.serviceRequests = containerMetrics.getBlkIOServiceCount();
            event.dataTransferred = containerMetrics.getBlkIOServiced();
            event.commit();
        }
    }

    private static void emitContainerCPUThrottling() {
        if (containerMetrics != null) {
            ContainerCPUThrottlingEvent event = new ContainerCPUThrottlingEvent();

src/jdk.jfr/share/classes/jdk/jfr/events/ContainerIOUsageEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "ContainerIOUsage")
@Label("Container IO Usage")
@Category({"Operating System", "File System"})
@Description("Container IO usage related information")
public class ContainerIOUsageEvent extends AbstractPeriodicEvent {

  @Label("Block IO Request Count")
  @Description("Number of block IO requests to the disk that have been issued by the container")
  public long serviceRequests;

  @Label("Block IO Transfer")
  @Description("Number of block IO bytes that have been transferred to/from the disk by the container")
  @DataAmount
  public long dataTransferred;
}

Event configuration settings across JFR profiles
Configuration enabled period
default true 30 s
profiling true 30 s

Event fields with their types and descriptions
Field Type Description
serviceRequests long Block IO Request Count Number of block IO requests to the disk that have been issued by the container
dataTransferred long: bytes Block IO Transfer Number of block IO bytes that have been transferred to/from the disk by the container

Types

Bytecode

14+

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Bytecode Instruction

Event fields with their types and descriptions
Field Type Description
bytecode string Instruction

Examples 3
tableswitch
aastore
invokeinterface

CalleeMethod

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Event fields with their types and descriptions
Field Type Description
type string Class
name string Method Name
descriptor string Method Descriptor

Examples 3
Example event data values and properties
descriptor string
(DDLorg/netlib/util/doubleW;Lorg/netlib/util/doubleW;Lorg/netlib/util/doubleW;)V
name string
dlartg
type string
org/netlib/lapack/Dlartg
Example event data values and properties
descriptor string
()I
name string
length
type string
java/lang/String
Example event data values and properties
descriptor string
([BI)C
name string
getChar
type string
java/lang/StringUTF16

ChunkHeader

14+

Chunk Header

Event fields with their types and descriptions
Field Type Description
payload array byte Payload

Class

Java Class

Event fields with their types and descriptions
Field Type Description
classLoader ClassLoader Class Loader
name Symbol Name
package Package Package
modifiers int Access Modifiers
hidden boolean 15+ Hidden

ClassLoader

Java Class Loader

Event fields with their types and descriptions
Field Type Description
type Class Type
name Symbol Name

CodeBlobType

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Code Blob Type

Event fields with their types and descriptions
Field Type Description
type string Type

Examples 3
CodeHeap 'non-nmethods'
CodeHeap 'non-nmethods'
CodeHeap 'non-profiled nmethods'

CompilerPhaseType

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Compiler Phase Type

Event fields with their types and descriptions
Field Type Description
phase string Phase

Examples 3
After Loop Optimizations
Before Iter GVN
Iter GVN 2

CompilerType

14+

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Compiler Type

Event fields with their types and descriptions
Field Type Description
compiler string Compiler

Examples 3

CopyFailed

Event fields with their types and descriptions
Field Type Description
objectCount ulong Object Count
firstSize ulong: bytes First Failed Object Size
smallestSize ulong: bytes Smallest Failed Object Size
totalSize ulong: bytes Total Object Size

DeoptimizationAction

14+

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Deoptimization Action

Event fields with their types and descriptions
Field Type Description
action string Action

Examples 3
maybe_recompile
maybe_recompile
reinterpret

DeoptimizationReason

14+

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Deoptimization Reason

Event fields with their types and descriptions
Field Type Description
reason string Reason

Examples 3
bimorphic_or_optimized_type_check
array_check
unstable_if

FlagValueOrigin

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Flag Value Origin

Event fields with their types and descriptions
Field Type Description
origin string Origin

Examples 3

FrameType

Frame type

Event fields with their types and descriptions
Field Type Description
description string Description

Examples 3

G1EvacuationStatistics

Appearing in: graalvm_linux_G1GC, linux_G1GC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
allocated ulong: bytes Allocated Total memory allocated by PLABs
wasted ulong: bytes Wasted Total memory wasted within PLABs due to alignment or refill
used ulong: bytes Used Total memory occupied by objects within PLABs
undoWaste ulong: bytes Undo Wasted Total memory wasted due to allocation undo within PLABs
regionEndWaste ulong: bytes Region End Wasted Total memory wasted at the end of regions due to refill
regionsRefilled uint Region Refills Number of regions refilled
numPlabsFilled ulong 17+ PLAB Fills Number of PLABs filled
directAllocated ulong: bytes Allocated (Direct) Total memory allocated using direct allocation outside of PLABs
numDirectAllocated ulong 17+ Direct Allocations Number of direct allocations
failureUsed ulong: bytes Used (Failure) Total memory occupied by objects in regions where evacuation failed
failureWaste ulong: bytes Wasted (Failure) Total memory left unused in regions where evacuation failed

Examples 3
Example event data values and properties
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1068
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
0
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0
Example event data values and properties
allocated ulong: bytes
437376
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1083
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
1
undoWaste ulong: bytes
0
used ulong: bytes
261992
wasted ulong: bytes
40
Example event data values and properties
allocated ulong: bytes
2097152
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
5
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
1
undoWaste ulong: bytes
0
used ulong: bytes
1967224
wasted ulong: bytes
63912

G1HeapRegionType

Appearing in: graalvm_linux_G1GC, linux_G1GC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

G1 Heap Region Type

Event fields with their types and descriptions
Field Type Description
type string Type

Examples 3

G1YCType

Appearing in: graalvm_linux_G1GC, linux_G1GC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

G1 YC Type

Event fields with their types and descriptions
Field Type Description
type string Type

Examples 3
Normal
Concurrent Start
Prepare Mixed

GCCause

GC Cause

Event fields with their types and descriptions
Field Type Description
cause string Cause

Examples 3
System.gc()
G1 Humongous Allocation
Heap Inspection Initiated GC

GCName

GC Name

Event fields with their types and descriptions
Field Type Description
name string Name

Examples 3

GCThresholdUpdater

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

GC Threshold Updater

Event fields with their types and descriptions
Field Type Description
updater string Updater

Examples 3
compute_new_size
compute_new_size
compute_new_size

GCWhen

GC When

Event fields with their types and descriptions
Field Type Description
when string When

Examples 3

InflateCause

Inflation Cause

Event fields with their types and descriptions
Field Type Description
cause string Cause

Examples 3
Monitor Wait
Monitor Wait
VM Internal

MetadataType

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Metadata Type

Event fields with their types and descriptions
Field Type Description
type string Type

Examples 3

MetaspaceObjectType

Metaspace Object Type

Event fields with their types and descriptions
Field Type Description
type string Type

MetaspaceSizes

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Event fields with their types and descriptions
Field Type Description
committed ulong: bytes Committed Committed memory for this space
used ulong: bytes Used Bytes allocated by objects in the space
reserved ulong: bytes Reserved Reserved memory for this space

Examples 3
Example event data values and properties
committed ulong: bytes
179175424
reserved ulong: bytes
1073741824
used ulong: bytes
177475112
Example event data values and properties
committed ulong: bytes
957546496
reserved ulong: bytes
1879048192
used ulong: bytes
953988624
Example event data values and properties
committed ulong: bytes
778371072
reserved ulong: bytes
805306368
used ulong: bytes
776513512

Method

Java Method

Event fields with their types and descriptions
Field Type Description
type Class Type
name Symbol Name
descriptor Symbol Descriptor
modifiers int Access Modifiers
hidden boolean Hidden

Module

Module

Event fields with their types and descriptions
Field Type Description
name Symbol Name
version Symbol Version
location Symbol Location
classLoader ClassLoader Class Loader

NMTType

21+

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Native Memory Tracking Type

Event fields with their types and descriptions
Field Type Description
name string Name

Examples 3

NarrowOopMode

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Narrow Oop Mode

Event fields with their types and descriptions
Field Type Description
mode string Mode

Examples 3

NetworkInterfaceName

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Network Interface

Event fields with their types and descriptions
Field Type Description
networkInterface string Network Interface Network Interface Name

Examples 3

ObjectSpace

Appearing in: linux_ParallelGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Event fields with their types and descriptions
Field Type Description
start ulong: address Start Address Start address of the space
end ulong: address End Address End address of the space
used ulong: bytes Used Bytes allocated by objects in the space
size ulong: bytes Size Size of the space

Examples 3
Example event data values and properties
end ulong: address
33996931072
size ulong: bytes
62914560
start ulong: address
33934016512
used ulong: bytes
5308448
Example event data values and properties
end ulong: address
33934016512
size ulong: bytes
970981376
start ulong: address
32963035136
used ulong: bytes
0
Example event data values and properties
end ulong: address
32398901248
size ulong: bytes
2231369728
start ulong: address
30167531520
used ulong: bytes
252581992

OldObject

Appearing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: linux_ShenandoahGC, linux_ZGC

Old Object

Event fields with their types and descriptions
Field Type Description
address ulong: address Memory Address
type Class Java Class
description string Object Description Object description
referrer Reference Referrer Object Object referencing this object

Examples 3
Example event data values and properties
address ulong: address
30224175704
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/ConcurrentHashMap
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent
Example event data values and properties
address ulong: address
30207367288
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
Example event data values and properties
address ulong: address
30174075600
description string
Class Name: java.lang.ref.Finalizer$1
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Class
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang

OldObjectArray

Old Object Array

Event fields with their types and descriptions
Field Type Description
size int Array Size Size of array
index int Index Index in the array

OldObjectField

Old Object Field

Event fields with their types and descriptions
Field Type Description
name string Field Name of field
modifiers short Field Modifiers Field modifiers

OldObjectGcRoot

Appearing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: linux_ShenandoahGC, linux_ZGC

GC Root

Event fields with their types and descriptions
Field Type Description
description string Root Description Root information
system OldObjectRootSystem System The subsystem of origin for the root
type OldObjectRootType Type The root type

Examples 3

OldObjectRootSystem

GC Root System

Event fields with their types and descriptions
Field Type Description
system string System

OldObjectRootType

GC Root Type

Event fields with their types and descriptions
Field Type Description
type string Type

Package

Package

Event fields with their types and descriptions
Field Type Description
name Symbol Name
module Module Module
exported boolean Exported

Reference

Appearing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: linux_ShenandoahGC, linux_ZGC

Reference

Event fields with their types and descriptions
Field Type Description
array OldObjectArray Array Information Array or null if it is not an array
field OldObjectField Field Information Field or null if it is an array
object OldObject Object Object holder for this reference
skip int Skip Value The object is this many hops away

Examples 3

ReferenceType

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Reference Type

Event fields with their types and descriptions
Field Type Description
type string Type

Examples 3
Phantom reference
Weak reference
Final reference

ShenandoahHeapRegionState

Appearing in: linux_ShenandoahGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ZGC

Shenandoah Heap Region State

Event fields with their types and descriptions
Field Type Description
state string State

Examples 3
Empty Uncommitted
Humongous Continuation
Empty Committed

StackFrame

Event fields with their types and descriptions
Field Type Description
method Method Java Method
lineNumber int Line Number
bytecodeIndex int Bytecode Index
type FrameType Frame Type

Examples 3
Example event data values and properties
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
type FrameType
Native
Example event data values and properties
bytecodeIndex int
1
lineNumber int
273
method Method
descriptor string
(I)[D
hidden boolean
false
modifiers int
1
name string
newArray
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
25
name string
scala/reflect/ManifestFactory$DoubleManifest
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/reflect
type FrameType
Inlined
Example event data values and properties
bytecodeIndex int
35
lineNumber int
134
method Method
descriptor string
()Lbreeze/linalg/DenseVector;
hidden boolean
false
modifiers int
1
name string
copy$mcD$sp
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
breeze/linalg/DenseVector$mcD$sp
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg
type FrameType
Inlined

StackTrace

Stacktrace

Event fields with their types and descriptions
Field Type Description
truncated boolean Truncated
frames array StackFrame struct Stack Frames

Symbol

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Symbol

Event fields with their types and descriptions
Field Type Description
string string String

Examples 3
resource:///shared/netty-buffer-4.1.114.Final.jar
resource:///shared/netty-buffer-4.1.114.Final.jar
resource:///unique/database/chronicle-core-2.26ea2.jar

Thread

Thread

Event fields with their types and descriptions
Field Type Description
osName string OS Thread Name
osThreadId long OS Thread Id
javaName string Java Thread Name
javaThreadId long Java Thread Id
group ThreadGroup Java Thread Group
virtual boolean 19+ Virtual Thread

ThreadGroup

Thread Group

Event fields with their types and descriptions
Field Type Description
parent ThreadGroup Parent
name string Name

Examples 3
Example event data values and properties
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
null
Example event data values and properties
name string
system
parent ThreadGroup
null

ThreadState

Java Thread State

Event fields with their types and descriptions
Field Type Description
name string Name

Examples 3
STATE_RUNNABLE
STATE_RUNNABLE
STATE_RUNNABLE

VMOperationType

VM Operation Type

Event fields with their types and descriptions
Field Type Description
type string Type

Examples 3
G1PauseRemark
HandshakeAllThreads
G1CollectForAllocation

VMThreadState

25+

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

JVM Thread State

Event fields with their types and descriptions
Field Type Description
state string State

Examples 3
_thread_in_Java
_thread_in_Java
_thread_in_Java

VirtualSpace

Event fields with their types and descriptions
Field Type Description
start ulong: address Start Address Start address of the virtual space
committedEnd ulong: address Committed End Address End address of the committed memory for the virtual space
committedSize ulong: bytes Committed Size Size of the committed memory for the virtual space
reservedEnd ulong: address Reserved End Address End address of the reserved memory for the virtual space
reservedSize ulong: bytes Reserved Size Size of the reserved memory for the virtual space

Examples 3
Example event data values and properties
committedEnd ulong: address
31046238208
committedSize ulong: bytes
878706688
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
Example event data values and properties
committedEnd ulong: address
30234640384
committedSize ulong: bytes
67108864
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
Example event data values and properties
committedEnd ulong: address
33439088640
committedSize ulong: bytes
3271557120
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520

ZPageTypeType

15+

Appearing in: linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Z Page Type

Event fields with their types and descriptions
Field Type Description
type string Type

Examples 3

ZStatisticsCounterType

Appearing in: linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Z Statistics Counter

Event fields with their types and descriptions
Field Type Description
counter string Counter

Examples 1
Allocation Rate

ZStatisticsSamplerType

Appearing in: linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Z Statistics Sampler

Event fields with their types and descriptions
Field Type Description
sampler string Sampler

Examples 2
Uncommit
Concurrent Relocate

XML Content Types

address

Annotation: jdk.jfr.MemoryAddress

Examples 3
30377246720
30362878480
140616843402656

bits-per-second

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Annotation: jdk.jfr.DataAmount(BITS), jdk.jfr.Frequency

Examples 3

bytes

Annotation: jdk.jfr.DataAmount(BYTES)

Examples 3

bytes-per-second

Annotation: jdk.jfr.DataAmount(BYTES), jdk.jfr.Frequency

certificateId

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Annotation: jdk.jfr.events.CertificateId

Examples 3
998794918
2389201834
792571453

epochmillis

Annotation: jdk.jfr.Timestamp(MILLISECONDS_SINCE_EPOCH)

Examples 3
1788871449128
-9223372036854775808
1788871449508

hertz

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Annotation: jdk.jfr.Frequency

Examples 3

microseconds

17+

Annotation: jdk.jfr.Timespan(MICROSECONDS)

millis

Annotation: jdk.jfr.Timespan(MILLISECONDS)

Examples 3
453308905577
452967115103
452967990695

nanos

Annotation: jdk.jfr.Timespan(NANOSECONDS)

Examples 3
10000000
9999999
-9223372036854775808

percentage

Annotation: jdk.jfr.Percentage

Examples 3

tickspan

Annotation: jdk.jfr.Timespan(TICKS)

Examples 3

tickstamp

Annotation: jdk.jfr.Timestamp(TICKS)

XML Types

Class

Property Value
Parameter Type const Klass*
Field Type const Klass*
Java Type java.lang.Class
Examples 3
null
null
Example event data values and properties
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionObject
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent/locks

ClassLoader

Property Value
Parameter Type const ClassLoaderData*
Field Type const ClassLoaderData*
Examples 3
Example event data values and properties
name string
bootstrap
type Class
null
Example event data values and properties
name string
bootstrap
type Class
null
Example event data values and properties
name string
bootstrap
type Class
null

Method

Property Value
Parameter Type const Method*
Field Type const Method*
Examples 3
Example event data values and properties
descriptor string
(I)[D
hidden boolean
false
modifiers int
1
name string
newArray
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
25
name string
scala/reflect/ManifestFactory$DoubleManifest
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/reflect
Example event data values and properties
descriptor string
()Lbreeze/linalg/DenseVector;
hidden boolean
false
modifiers int
1
name string
copy$mcD$sp
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
breeze/linalg/DenseVector$mcD$sp
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg
Example event data values and properties
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc

Module

Property Value
Parameter Type const ModuleEntry*
Field Type const ModuleEntry*
Examples 3
Example event data values and properties
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
Example event data values and properties
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
Example event data values and properties
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1

Package

Property Value
Parameter Type const PackageEntry*
Field Type const PackageEntry*
Examples 3
Example event data values and properties
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent/locks
Example event data values and properties
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
Example event data values and properties
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net

StackTrace

15+

Property Value
Parameter Type u8
Field Type u8
Java Type jdk.types.StackTrace
Examples 3
Example event data values and properties
frames StackFrame
bytecodeIndex int
35
lineNumber int
134
method Method
descriptor string
()Lbreeze/linalg/DenseVector;
hidden boolean
false
modifiers int
1
name string
copy$mcD$sp
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
breeze/linalg/DenseVector$mcD$sp
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg
type FrameType
Inlined
…
truncated boolean
false
Example event data values and properties
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
type FrameType
Native
…
truncated boolean
false
Example event data values and properties
frames StackFrame
bytecodeIndex int
1
lineNumber int
273
method Method
descriptor string
(I)[D
hidden boolean
false
modifiers int
1
name string
newArray
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
25
name string
scala/reflect/ManifestFactory$DoubleManifest
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/reflect
type FrameType
Inlined
…
truncated boolean
false

Thread

Property Value
Parameter Type u8
Field Type u8
Java Type java.lang.Thread
Examples 3
Example event data values and properties
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 2.0 in stage 47.0 (TID 184)
javaThreadId long
1733
osName string
Executor task launch worker for task 2.0 in stage 47.0 (TID 184)
osThreadId long
4650
virtual boolean
false
Example event data values and properties
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 3.0 in stage 47.0 (TID 185)
javaThreadId long
1729
osName string
Executor task launch worker for task 3.0 in stage 47.0 (TID 185)
osThreadId long
4645
virtual boolean
false
Example event data values and properties
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 0.0 in stage 38.0 (TID 146)
javaThreadId long
1711
osName string
Executor task launch worker for task 0.0 in stage 38.0 (TID 146)
osThreadId long
4234
virtual boolean
false

Ticks

unsigned

Property Value
Parameter Type const Ticks&
Field Type Ticks
Java Type long
Content Type tickstamp
Examples 3
441627297902
86467254786
555050476

Tickspan

unsigned

Property Value
Parameter Type const Tickspan&
Field Type Tickspan
Java Type long
Content Type tickspan

boolean

Property Value
Parameter Type bool
Field Type bool
Java Type boolean
Examples 3

byte

Property Value
Parameter Type s1
Field Type s1
Java Type byte

char

Property Value
Parameter Type char
Field Type char
Java Type char

double

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Property Value
Parameter Type double
Field Type double
Java Type double
Examples 3

float

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Property Value
Parameter Type float
Field Type float
Java Type float
Examples 3

int

Property Value
Parameter Type s4
Field Type s4
Java Type int
Examples 3

long

Property Value
Parameter Type s8
Field Type s8
Java Type long
Examples 3

short

Property Value
Parameter Type s2
Field Type s2
Java Type short

string

Property Value
Parameter Type const char*
Field Type const char*
Java Type java.lang.String
Examples 3
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionObject
bootstrap
java/util/concurrent/locks

ubyte

unsigned

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Property Value
Parameter Type u1
Field Type u1
Java Type byte
Examples 3

uint

unsigned

Property Value
Parameter Type unsigned
Field Type unsigned
Java Type int
Examples 3

ulong

unsigned

Property Value
Parameter Type u8
Field Type u8
Java Type long
Examples 3

ushort

unsigned

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native

Property Value
Parameter Type u2
Field Type u2
Java Type short
Examples 3