Introduction

The following are the events for OpenJDK 20 (jdk-20.0.2+9, permalink, 18-January-2026), and Graal VM 23.0.1 (jdk-20.0.2) . The events are collected from the event configuration and the source code. Visit the jfreventcollector repository for more information. This is also the place 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.

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

profiling default startTime 11 17 21 25 26 27

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:

static void post_events(bool exception_handler, Thread* thread) {
  if (exception_handler) {
    EventShutdown e;
    e.set_reason("VM Error");
    e.commit();
  } else {
    // OOM
    LeakProfiler::emit_events(max_jlong, false, false);
  }
  EventDumpReason event;
  event.set_reason(exception_handler ? "Crash" : "Out of Memory");
  event.set_recordingId(-1);
  event.commit();
}

void JfrEmergencyDump::on_vm_shutdown(bool exception_handler) {
  if (!guard_reentrancy()) {
    return;
  }
  Thread* thread = Thread::current_or_null_safe();
  if (thread == NULL) {

Configuration enabled
profiling true
default true

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

profiling default startTime 11 17 21 25 26 27 graal vm

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 != NULL, "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 != NULL, "invariant");
  const size_t unflushed_size = buffer->unflushed_size();
  buffer->reinitialize();

Configuration enabled
profiling true
default true

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 26 27

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/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:

Configuration enabled threshold
profiling false 0 ns
default false 0 ns

Field Type Description
flushId ulong Flush Identifier
elements ulong Elements Written
size ulong: bytes Size Written

Examples 3
elements ulong
3814
flushId ulong
204
size ulong: bytes
943339
startTime long: millis
404961302690
elements ulong
445
flushId ulong
220
size ulong: bytes
388749
startTime long: millis
476128986689
elements ulong
1499
flushId ulong
243
size ulong: bytes
339567
startTime long: millis
335388006092

ActiveRecording

profiling default startTime duration stackTrace 11 17 21 25 26 27

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/events/ActiveRecordingEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "ActiveRecording")
@Label("Flight Recording")
@Category("Flight Recorder")
@StackTrace(false)
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")

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

    private void finishChunk(RepositoryChunk chunk, Instant time, PlatformRecording ignoreMe) {
        chunk.finish(time);
        for (PlatformRecording r : getRecordings()) {
            if (r != ignoreMe && r.getState() == RecordingState.RUNNING) {
                r.appendChunk(chunk);
            }
        }
        FilePurger.purge();
    }

    private void writeMetaEvents() {
        long timestamp = JVM.counterTime();
        if (ActiveRecordingEvent.enabled()) {
            for (PlatformRecording r : getRecordings()) {
                if (r.getState() == RecordingState.RUNNING && r.shouldWriteMetadataEvent()) {
                    WriteableUserPath 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,
                        0L,
                        r.getId(),
                        r.getName(),
                        path == null ? null : path.getRealPathText(),
                        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/internal/instrument/JDKEvents.java:

        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ExceptionThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ErrorThrownEvent.class,
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.SecurityProviderServiceEvent.class,
        jdk.internal.event.ThreadSleepEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.VirtualThreadStartEvent.class,
        jdk.internal.event.VirtualThreadEndEvent.class,
        jdk.internal.event.VirtualThreadPinnedEvent.class,
        jdk.internal.event.VirtualThreadSubmitFailedEvent.class,
        jdk.internal.event.X509CertificateEvent.class,

Configuration enabled
profiling true
default true

Field Type Description
id long Id
name string Name
destination string Destination
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
destination string
/home/runner/work/jfrevents/jfrevents/jfr/sample_UseParallelGC.jfr
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
1767487168217
stackTrace StackTrace
null
startTime long: millis
467537648213
destination string
/home/runner/work/jfrevents/jfrevents/jfr/sample_UseG1GC.jfr
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
1767487167450
stackTrace StackTrace
null
startTime long: millis
349025952000
destination string
/home/runner/work/jfrevents/jfrevents/jfr/sample_UseSerialGC.jfr
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
1767487156514
stackTrace StackTrace
null
startTime long: millis
477911985385

ActiveSetting

profiling default startTime duration stackTrace 11 17 21 25 26 27

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/events/ActiveSettingEvent.java:

package jdk.jfr.events;

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

@Name(Type.EVENT_NAME_PREFIX + "ActiveSetting")
@Label("Recording Setting")
@Category("Flight Recorder")
@StackTrace(false)
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")

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

    void writeActiveSettingEvent(long timestamp) {
        if (!type.isRegistered()) {
            return;
        }
        for (NamedControl nc : namedControls) {
            if (Utils.isSettingVisible(nc.control, type.hasEventHook()) && type.isVisible()) {
                String value = nc.control.getLastValue();
                if (value == null) {
                    value = nc.control.getDefaultValue();
                }
                if (ActiveSettingEvent.enabled()) {
                    ActiveSettingEvent.commit(timestamp, 0L, type.getId(), nc.name(), value);
                }
            }
        }
    }

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

    public PlatformEventType getEventType() {
        return type;

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

                        0L,
                        r.getId(),
                        r.getName(),
                        path == null ? null : path.getRealPathText(),
                        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 (!jvm.hasNativeJFR()) {
            return;
        }
        while (true) {

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

        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ExceptionThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ErrorThrownEvent.class,
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.SecurityProviderServiceEvent.class,
        jdk.internal.event.ThreadSleepEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.VirtualThreadStartEvent.class,
        jdk.internal.event.VirtualThreadEndEvent.class,
        jdk.internal.event.VirtualThreadPinnedEvent.class,
        jdk.internal.event.VirtualThreadSubmitFailedEvent.class,

Configuration enabled
profiling true
default true

Field Type Description
id long Event Id
name string Setting Name
value string Setting Value

Examples 3
id long
7
name string
period
stackTrace StackTrace
null
startTime long: millis
378896523380
value string
1000 ms
id long
1519
name string
enabled
stackTrace StackTrace
null
startTime long: millis
371338931988
value string
true
id long
45
name string
enabled
stackTrace StackTrace
null
startTime long: millis
278162944220
value string
true

JVM

JVMInformation

profiling default startTime duration end of every chunk 11 17 21 25 26 27 graal vm

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/jfrPeriodic.cpp:

Ticks JfrPeriodicEventSet::_timestamp;
PeriodicType JfrPeriodicEventSet::_type;

Ticks JfrPeriodicEventSet::timestamp(void) {
  return _timestamp;
}

PeriodicType JfrPeriodicEventSet::type(void) {
  return _type;
}

TRACE_REQUEST_FUNC(JVMInformation) {
  ResourceMark rm;
  EventJVMInformation event;
  event.set_jvmName(VM_Version::vm_name());
  event.set_jvmVersion(VM_Version::internal_vm_info_string());
  event.set_javaArguments(Arguments::java_command());
  event.set_jvmArguments(Arguments::jvm_args());
  event.set_jvmFlags(Arguments::jvm_flags());
  event.set_jvmStartTime(Management::vm_init_done_time());
  event.set_pid(os::current_process_id());
  event.commit();
 }

TRACE_REQUEST_FUNC(OSInformation) {

Configuration enabled period
profiling true beginChunk
default true beginChunk

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
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_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
1767487166908
jvmVersion string
OpenJDK 64-Bit Server VM (21.0.9+10-LTS) for linux-amd64 JRE (21.0.9+10-LTS), built on 2025-10-17T14:44:04Z by "jenkinsi" with gcc 11.3.0
pid long
2289
startTime long: millis
293393765459
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_UseSerialGC.jfr,settings=/home/runner/work/jfrevents/jfrevents/.cache/jfc.jfc -XX:+UseSerialGC
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1767487156005
jvmVersion string
OpenJDK 64-Bit Server VM (21.0.9+10-LTS) for linux-amd64 JRE (21.0.9+10-LTS), built on 2025-10-17T14:44:04Z by "jenkinsi" with gcc 11.3.0
pid long
2254
startTime long: millis
455876142949
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_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
1767487167754
jvmVersion string
OpenJDK 64-Bit Server VM (21.0.9+10-LTS) for linux-amd64 JRE (21.0.9+10-LTS), built on 2025-10-17T14:44:04Z by "jenkinsi" with gcc 11.3.0
pid long
2925
startTime long: millis
464312448090

InitialSystemProperty

profiling default startTime end of every chunk 11 17 21 25 26 27 graal vm

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/jfrPeriodic.cpp:

  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(conf.new_ratio());
  event.commit();
}

TRACE_REQUEST_FUNC(InitialSystemProperty) {
  SystemProperty* p = Arguments::system_properties();
  JfrTicks time_stamp = JfrTicks::now();
  while (p !=  NULL) {
    if (!p->internal()) {
      EventInitialSystemProperty event(UNTIMED);
      event.set_key(p->key());
      event.set_value(p->value());
      event.set_starttime(time_stamp);
      event.set_endtime(time_stamp);
      event.commit();
    }
    p = p->next();
  }
}

TRACE_REQUEST_FUNC(ThreadAllocationStatistics) {

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
key string Key
value string Value

Examples 3
key string
java.vm.specification.vendor
startTime long: millis
278169436152
value string
Oracle Corporation
key string
java.class.path
startTime long: millis
398096347192
value string
/home/runner/work/jfrevents/jfrevents/.cache/renaissance.jar
key string
sun.boot.library.path
startTime long: millis
378900891079
value string
/opt/hostedtoolcache/Java_SapMachine_jdk/21.0.9/x64/lib

JVM: Class Loading

ClassLoad

startTime duration eventThread stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / Class Loading

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;

class SystemDictionary : AllStatic {
  friend class BootstrapInfo;
  friend class vmClasses;
  friend class VMStructs;

 public:

  // Returns a class with a given class name and class loader.  Loads the
  // class if needed. If not found a NoClassDefFoundError or a

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

                                           Handle class_loader);
  static bool check_shared_class_super_type(InstanceKlass* klass, InstanceKlass* super,
                                            Handle class_loader,  Handle protection_domain,
                                            bool is_superclass, TRAPS);
  static bool check_shared_class_super_types(InstanceKlass* ik, Handle class_loader,
                                               Handle protection_domain, TRAPS);
  // Second part of load_shared_class
  static void load_shared_class_misc(InstanceKlass* ik, ClassLoaderData* loader_data) NOT_CDS_RETURN;
protected:
  // Used by SystemDictionaryShared

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

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

        InstanceKlass* check = loader_data->dictionary()->find_class(current, name);
        if (check != NULL) {
          // Klass is already loaded, so just return it
          return check;
        }
        // check if other thread failed to load and cleaned up
        oldprobe = PlaceholderTable::get_entry(name, loader_data);
      }
    }
  }
  return NULL;
}

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

// 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,
                                                                Handle protection_domain,
                                                                TRAPS) {
  // name must be in the form of "java/lang/Object" -- cannot be "Ljava/lang/Object;"
  assert(name != NULL && !Signature::is_array(name) &&
         !Signature::has_envelope(name), "invalid class name");

  EventClassLoad class_load_start_event;

  HandleMark hm(THREAD);

  // Fix for 4474172; see evaluation for more details
  class_loader = Handle(THREAD, java_lang_ClassLoader::non_reflection_class_loader(class_loader()));
  ClassLoaderData* loader_data = register_loader(class_loader);
  Dictionary* dictionary = loader_data->dictionary();

  // Do lookup to see if class already exists and the protection domain
  // has the right access.
  // This call uses find which checks protection domain already matches

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_start_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 != NULL, "invariant");
  assert(st->need_verify(), "invariant");

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

  InstanceKlass* loaded_lambda =
    SystemDictionary::load_shared_lambda_proxy_class(lambda_ik, class_loader, protection_domain, pkg_entry, CHECK_NULL);

  if (loaded_lambda == NULL) {
    return NULL;
  }

  // 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_start_event;
  {
    MutexLocker mu_r(THREAD, Compile_lock);

    // Add to class hierarchy, and do possible deoptimizations.
    SystemDictionary::add_to_hierarchy(loaded_lambda);
    // But, do not add to dictionary.
  }
  loaded_lambda->link_class(CHECK_NULL);
  // notify jvmti
  if (JvmtiExport::should_post_class_load()) {
    JvmtiExport::post_class_load(THREAD, loaded_lambda);

Configuration enabled stackTrace threshold
profiling false true 0 ms
default false true 0 ms

Field Type Description
loadedClass Class Loaded Class
definingClassLoader ClassLoader Defining Class Loader
initiatingClassLoader ClassLoader Initiating Class Loader

Examples 3
definingClassLoader ClassLoader
null
initiatingClassLoader ClassLoader
null
loadedClass Class
classLoader ClassLoader
null
hidden boolean
true
modifiers int
16
name string
java.lang.invoke.LambdaForm$MH/0x00007f307527a000
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
java/lang/invoke
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/Class;Ljava/lang/String;[BIILjava/security/ProtectionDomain;ZILjava/lang/Object;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
java/lang
type FrameType
Native
truncated boolean
true
startTime long: millis
387308199586
definingClassLoader ClassLoader
null
initiatingClassLoader ClassLoader
null
loadedClass Class
classLoader ClassLoader
null
hidden boolean
true
modifiers int
16
name string
java.lang.invoke.LambdaForm$MH/0x00007fb961441000
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
21.0.9
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
21.0.9
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
415698396221
definingClassLoader ClassLoader
null
initiatingClassLoader ClassLoader
null
loadedClass Class
classLoader ClassLoader
null
hidden boolean
true
modifiers int
16
name string
java.lang.invoke.LambdaForm$MH/0x00007f58d93f7000
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
21.0.9
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
21.0.9
name string
java/lang
type FrameType
Native
truncated boolean
true
startTime long: millis
280672501017

ClassDefine

startTime eventThread stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / Class Loading

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.cpp:

      // during compilations.
      MutexLocker mu(THREAD, Compile_lock);
      update_dictionary(THREAD, loaded_class, class_loader);
    }

    if (JvmtiExport::should_post_class_load()) {
      JvmtiExport::post_class_load(THREAD, loaded_class);
    }
  }
  return loaded_class;
}

static void post_class_define_event(InstanceKlass* k, const ClassLoaderData* def_cld) {
  EventClassDefine event;
  if (event.should_commit()) {
    event.set_definedClass(k);
    event.set_definingClassLoader(def_cld);
    event.commit();
  }
}

void SystemDictionary::define_instance_class(InstanceKlass* k, Handle class_loader, TRAPS) {

  ClassLoaderData* loader_data = k->class_loader_data();
  assert(loader_data->class_loader() == class_loader(), "they must be the same");

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
definedClass Class Defined Class
definingClassLoader ClassLoader Defining Class Loader

Examples 3
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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
1537
name string
scala/reflect/internal/BaseTypeSeqs
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
scala/reflect/internal
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
21.0.9
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
21.0.9
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
431343463091
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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
1537
name string
scala/reflect/api/StandardNames
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
scala/reflect/api
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
21.0.9
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
21.0.9
name string
java/lang
type FrameType
Native
truncated boolean
true
startTime long: millis
428523996750
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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
17
name string
org/apache/spark/sql/SQLImplicits$$typecreator1$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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/sql
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
21.0.9
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
21.0.9
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
310092042496

ClassRedefinition

profiling default startTime 15 17 21 25 26 27

Category: Java Virtual Machine / Class Loading

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() != NULL) {
    // 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
    log_info(redefine, class, load)

Configuration enabled
profiling true
default true

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

RedefineClasses

profiling default startTime duration eventThread stackTrace 15 17 21 25 26 27

Category: Java Virtual Machine / Class Loading

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 */

Configuration enabled stackTrace threshold
profiling true true 0 ms
default true true 0 ms

Field Type Description
classCount int Class Count
redefinitionId ulong Class Redefinition Id

RetransformClasses

profiling default startTime duration eventThread stackTrace 15 17 21 25 26 27

Category: Java Virtual Machine / Class Loading

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 */

Configuration enabled stackTrace threshold
profiling true true 0 ms
default true true 0 ms

Field Type Description
classCount int Class Count
redefinitionId ulong Class Redefinition Id

ClassUnload

startTime eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Class Loading

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 != NULL, "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.

Configuration enabled
profiling false
default false

Field Type Description
unloadedClass Class Unloaded Class
definingClassLoader ClassLoader Defining Class Loader

Examples 3
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
21.0.9
name string
java/net
startTime long: millis
448432463124
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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
17
name string
scala/collection/Seq$
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection
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
21.0.9
name string
java/net
startTime long: millis
437555893356
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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
1537
name string
scala/collection/StrictOptimizedMapOps
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection
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
21.0.9
name string
java/net
startTime long: millis
315473634351
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
21.0.9
name string
java/net
hidden boolean
true
modifiers int
4112
name string
org.renaissance.jdk.streams.MnemonicsCoderWithStream$$Lambda/0x00007f58d95a6480
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
org/renaissance/jdk/streams

JVM: Code Cache

CodeCacheFull

profiling default startTime eventThread 11 17 21 25 26 27

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());

Configuration enabled
profiling true
default true

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

profiling default startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Code Cache

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(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();
    }
  }

Configuration enabled period
profiling true everyChunk
default true everyChunk

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
adaptorCount int
2310
codeBlobType CodeBlobType
CodeHeap 'non-nmethods'
entryCount int
2407
fullCount int
0
methodCount int
0
reservedTopAddress ulong: address
140435300057088
startAddress ulong: address
140435294220288
startTime long: millis
388177885297
unallocatedCapacity ulong: bytes
2866176
adaptorCount int
2458
codeBlobType CodeBlobType
CodeHeap 'non-nmethods'
entryCount int
2557
fullCount int
0
methodCount int
0
reservedTopAddress ulong: address
140021238366208
startAddress ulong: address
140021232529408
startTime long: millis
351915548864
unallocatedCapacity ulong: bytes
1676032
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'profiled nmethods'
entryCount int
5301
fullCount int
0
methodCount int
5301
reservedTopAddress ulong: address
139847420571648
startAddress ulong: address
139847297662976
startTime long: millis
443486820863
unallocatedCapacity ulong: bytes
106757632

CodeCacheConfiguration

profiling default startTime end of every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Code Cache

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();
}

Configuration enabled period
profiling true beginChunk
default true beginChunk

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
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
5832780
nonProfiledSize ulong: bytes
122912730
profiledSize ulong: bytes
122912730
reservedSize ulong: bytes
251658240
reservedTopAddress ulong: address
140021361278976
startAddress ulong: address
140021109620736
startTime long: millis
293412527411
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
5832780
nonProfiledSize ulong: bytes
122912730
profiledSize ulong: bytes
122912730
reservedSize ulong: bytes
251658240
reservedTopAddress ulong: address
139847549321216
startAddress ulong: address
139847297662976
startTime long: millis
383182307150
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
5832780
nonProfiledSize ulong: bytes
122912730
profiledSize ulong: bytes
122912730
reservedSize ulong: bytes
251658240
reservedTopAddress ulong: address
140435422969856
startAddress ulong: address
140435171311616
startTime long: millis
455890101967

JVM: Compiler

JITRestart

profiling default startTime eventThread 17 21 25 26 27

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:

    freed_memory += nm->total_size();
    nm->flush();
    if (next == nm) {
      // Self looped means end of list
      break;
    }
    nm = next;
  }

  // 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;
nmethod* volatile CodeCache::_unlinked_head = NULL;

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

Configuration enabled
profiling true
default true

Field Type Description
freedMemory ulong: bytes Freed Memory
codeCacheMaxCapacity ulong: bytes Code Cache Maximum Capacity

Compilation

profiling default startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Compiler

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/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 != NULL, "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());
}

int DirectivesStack::_depth = 0;

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

  // Allocate a new set of JNI handles.
  JNIHandleMark jhm(thread);
  Method* target_handle = task->method();
  int compilable = ciEnv::MethodCompilable;
  const char* failure_reason = NULL;
  bool failure_reason_on_C_heap = false;
  const char* retry_message = NULL;

#if INCLUDE_JVMCI
  if (UseJVMCICompiler && comp != NULL && comp->is_jvmci()) {
    JVMCICompiler* jvmci = (JVMCICompiler*) comp;

    TraceTime t1("compilation", &time);
    EventCompilation event;
    JVMCICompileState compile_state(task, jvmci);
    JVMCIRuntime *runtime = NULL;

    if (JVMCI::in_shutdown()) {
      failure_reason = "in JVMCI shutdown";
      retry_message = "not retryable";
      compilable = ciEnv::MethodCompilable_never;
    } else if (compile_state.target_method_is_old()) {
      // Skip redefined methods
      failure_reason = "redefined method";
      retry_message = "not retryable";

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 == NULL) {
      ci_env.record_method_not_compilable("no compiler");
    } else if (!ci_env.failing()) {
      if (WhiteBoxAPI && WhiteBox::compilation_locked) {
        MonitorLocker locker(Compilation_lock, Mutex::_no_safepoint_check_flag);
        while (WhiteBox::compilation_locked) {
          locker.wait();
        }
      }
      comp->compile_method(&ci_env, target, osr_bci, true, directive);

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) 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:

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

// As part of event commit, a Method* is tagged as a function of an epoch.
// Epochs evolve during safepoints. To ensure the event is tagged in the correct epoch,
// that is, to avoid a race, the thread will participate in the safepoint protocol
// by transitioning from _thread_in_native to _thread_in_vm.
template <typename EventType>
static inline void commit(EventType& event) {
  ThreadInVMfromNative transition(JavaThread::current());
  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) {
  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);
  commit(event);
}

src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/EmptyEventProvider.java:

package jdk.vm.ci.hotspot;

/**
 * An empty implementation for {@link EventProvider}. This implementation is used when no logging is
 * requested.
 */
final class EmptyEventProvider implements EventProvider {

    static InternalError shouldNotReachHere() {
        throw new InternalError("should not reach here");
    }

    @Override
    public CompilationEvent newCompilationEvent() {
        return new EmptyCompilationEvent();
    }

    static class EmptyCompilationEvent implements CompilationEvent {
        @Override
        public void commit() {
            throw shouldNotReachHere();
        }

        @Override
        public boolean shouldWrite() {
            // Events of this class should never been written.
            return false;
        }

src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/EventProvider.java:

     * Creates and returns an empty implementation for {@link EventProvider}. This implementation
     * can be used when no logging is requested.
     */
    static EventProvider createEmptyEventProvider() {
        return new EmptyEventProvider();
    }

    /**
     * Creates and returns an empty implementation for {@link CompilationEvent}.
     */
    static CompilationEvent createEmptyCompilationEvent() {
        return new EmptyCompilationEvent();
    }

    /**
     * Creates and returns an empty implementation for {@link CompilationEvent}.
     */
    static CompilerFailureEvent createEmptyCompilerFailureEvent() {
        return new EmptyCompilerFailureEvent();
    }

    /**
     * An instant event is an event that is not considered to have taken any time.

src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/EventProvider.java:

        /**
         * Ends the timing period for this event.
         */
        void end();
    }

    /**
     * Creates a new {@link CompilationEvent}.
     *
     * @return a compilation event
     */
    CompilationEvent newCompilationEvent();

    /**
     * A compilation event.
     */
    public interface CompilationEvent extends TimedEvent {
        void setMethod(String method);

        void setCompileId(int compileId);

        void setCompileLevel(int compileLevel);

        void setSucceeded(boolean succeeded);

Configuration enabled threshold
profiling true 100 ms
default true 1000 ms

Field Type Description
compileId uint 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

Examples 3
codeSize ulong: bytes
4848
compileId uint
74151
compileLevel ushort
4
compiler CompilerType
c2
inlinedBytes ulong: bytes
276
isOsr boolean
false
method Method
descriptor string
(IDLscala/reflect/ClassTag;)V
hidden boolean
false
modifiers int
1
name string
<init>
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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/util/collection/OpenHashSet
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/util/collection
startTime long: millis
291347586511
succeded boolean
true
codeSize ulong: bytes
42024
compileId uint
85908
compileLevel ushort
4
compiler CompilerType
c2
inlinedBytes ulong: bytes
5161
isOsr boolean
false
method Method
descriptor string
()Ljava/lang/Object;
hidden boolean
false
modifiers int
4161
name string
run
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/net/URLClassLoader$1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
java/net
startTime long: millis
468714963000
succeded boolean
true
codeSize ulong: bytes
38672
compileId uint
93211
compileLevel ushort
4
compiler CompilerType
c2
inlinedBytes ulong: bytes
8607
isOsr boolean
false
method Method
descriptor string
(Ldotty/tools/dotc/core/Types$Type;ZLdotty/tools/dotc/core/Contexts$Context;Ldotty/tools/dotc/core/Denotations$Denotation;Ldotty/tools/dotc/core/Denotations$SingleDenotation;)Ldotty/tools/dotc/core/Denotations$Denotation;
hidden boolean
false
modifiers int
18
name string
mergeDenot$1
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
java/net
hidden boolean
false
modifiers int
1033
name string
dotty/tools/dotc/core/Denotations$Denotation
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
dotty/tools/dotc/core
startTime long: millis
463625263246
succeded boolean
true

CompilerPhase

profiling default startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Compiler

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/opto/compile.cpp:

    Node* n = macro_node(i);
    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 cpt, int level, Node* n) {
  EventCompilerPhase event;
  if (event.should_commit()) {
    CompilerEvent::PhaseEvent::post(event, C->_latest_stage_start_counter, cpt, C->_compile_id, level);
  }
#ifndef PRODUCT
  ResourceMark rm;
  stringStream ss;
  ss.print_raw(CompilerPhaseTypeHelper::to_description(cpt));
  if (n != nullptr) {
    ss.print(": %d %s ", n->_idx, NodeClassNames[n->Opcode()]);
  }

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

// Only used from CompileWrapper
void Compile::begin_method() {
#ifndef PRODUCT
  if (_method != NULL && 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;
  if (event.should_commit()) {
    CompilerEvent::PhaseEvent::post(event, C->_latest_stage_start_counter, PHASE_END, C->_compile_id, 1);
  }

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

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/compiler/compilerEvent.cpp:

  event.set_succeded(success);
  event.set_isOsr(is_osr);
  event.set_codeSize(code_size);
  event.set_inlinedBytes(inlined_bytecodes);
  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/jvmci/jvmciCompilerToVM.cpp:

C2V_VMENTRY_0(jint, registerCompilerPhase, (JNIEnv* env, jobject, jstring jphase_name))
#if INCLUDE_JFR
  JVMCIObject phase_name = JVMCIENV->wrap(jphase_name);
  const char *name = JVMCIENV->as_utf8_string(phase_name);
  return CompilerEvent::PhaseEvent::get_phase_id(name, true, true, true);
#else
  return -1;
#endif // !INCLUDE_JFR
}

C2V_VMENTRY(void, notifyCompilerPhaseEvent, (JNIEnv* env, jobject, jlong startTime, jint phase, jint compileId, jint level))
  EventCompilerPhase event;
  if (event.should_commit()) {
    CompilerEvent::PhaseEvent::post(event, startTime, phase, compileId, level);
  }
}

C2V_VMENTRY(void, notifyCompilerInliningEvent, (JNIEnv* env, jobject, jint compileId, ARGUMENT_PAIR(caller), ARGUMENT_PAIR(callee), jboolean succeeded, jstring jmessage, jint bci))
  EventCompilerInlining event;
  if (event.should_commit()) {
    Method* caller = UNPACK_PAIR(Method, caller);
    Method* callee = UNPACK_PAIR(Method, callee);
    JVMCIObject message = JVMCIENV->wrap(jmessage);

src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/JFR.java:

        /**
         * @return current JFR time stamp
         */
        public static long now() {
            return compilerToVM().ticksNow();
        }
    }

    /**
     * Helper methods for managing JFR CompilerPhase events. The events are defined in {see @code
     * src/share/jfr/metadata/metadata.xml}.
     */
    public static final class CompilerPhaseEvent {

        private static final ConcurrentHashMap<String, Integer> phaseToId = new ConcurrentHashMap<>();

        private static int getPhaseToId(String phaseName) {
            return phaseToId.computeIfAbsent(phaseName, k -> compilerToVM().registerCompilerPhase(phaseName));
        }

        /**
         * Commits a CompilerPhase event.
         *
         * @param startTime time captured at the start of compiler phase

Configuration enabled threshold
profiling true 10 s
default true 60 s

Field Type Description
phase CompilerPhaseType Compile Phase
compileId uint Compilation Identifier
phaseLevel ushort Phase Level

CompilationFailure

profiling startTime eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Compiler

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.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) 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/compiler/compilerEvent.cpp:

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) {
  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);
  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/ci/ciEnv.cpp:

// ------------------------------------------------------------------
// ciEnv::record_failure()
void ciEnv::record_failure(const char* reason) {
  if (_failure_reason == NULL) {
    // Record the first failure reason.
    _failure_reason = 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) {

Configuration enabled
profiling true
default false

Field Type Description
failureMessage string Failure Message
compileId uint Compilation Identifier

Examples 3
compileId uint
90527
failureMessage string
retry without subsuming loads
startTime long: millis
346001800628
compileId uint
100876
failureMessage string
retry without subsuming loads
startTime long: millis
483731592329
compileId uint
93911
failureMessage string
retry without subsuming loads
startTime long: millis
464803784880

CompilerInlining

startTime eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Compiler / Optimization

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/opto/bytecodeInfo.cpp:

  CompileTask::print_inlining_ul(callee_method, inline_level(),
                                               caller_bci, inline_msg);
  if (C->print_inlining()) {
    C->print_inlining(callee_method, inline_level(), caller_bci, inline_msg);
    guarantee(callee_method != NULL, "would crash in CompilerEvent::InlineEvent::post");
    if (Verbose) {
      const InlineTree *top = this;
      while (top->caller_tree() != NULL) { top = top->caller_tree(); }
      //tty->print("  bcs: %d+%d  invoked: %d", top->count_inline_bcs(), callee_method->code_size(), callee_method->interpreter_invocation_count());
    }
  }
  EventCompilerInlining event;
  if (event.should_commit()) {
    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 != NULL, "caller checks for optimized virtual!");
  // Make sure the incoming jvms has the same information content as me.

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

void GraphBuilder::print_inlining(ciMethod* callee, const char* msg, bool success) {
  CompileLog* log = compilation()->log();
  if (log != NULL) {
    assert(msg != NULL, "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(), msg);

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

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);
  }

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

    // 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/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/jvmci/jvmciCompilerToVM.cpp:

#else
  return -1;
#endif // !INCLUDE_JFR
}

C2V_VMENTRY(void, notifyCompilerPhaseEvent, (JNIEnv* env, jobject, jlong startTime, jint phase, jint compileId, jint level))
  EventCompilerPhase event;
  if (event.should_commit()) {
    CompilerEvent::PhaseEvent::post(event, startTime, phase, compileId, level);
  }
}

C2V_VMENTRY(void, notifyCompilerInliningEvent, (JNIEnv* env, jobject, jint compileId, ARGUMENT_PAIR(caller), ARGUMENT_PAIR(callee), jboolean succeeded, jstring jmessage, jint bci))
  EventCompilerInlining event;
  if (event.should_commit()) {
    Method* caller = UNPACK_PAIR(Method, caller);
    Method* callee = UNPACK_PAIR(Method, callee);
    JVMCIObject message = JVMCIENV->wrap(jmessage);
    CompilerEvent::InlineEvent::post(event, compileId, caller, callee, succeeded, JVMCIENV->as_utf8_string(message), bci);
  }
}

C2V_VMENTRY(void, setThreadLocalObject, (JNIEnv* env, jobject, jint id, jobject value))
  requireInHotSpot("setThreadLocalObject", JVMCI_CHECK);
  if (id == 0) {

src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/JFR.java:

         * @param phaseName compiler phase name
         * @param compileId current compilation unit id
         * @param phaseLevel compiler phase nesting level
         */
        public static void write(long startTime, String phaseName, int compileId, int phaseLevel) {
            compilerToVM().notifyCompilerPhaseEvent(startTime, getPhaseToId(phaseName), compileId, phaseLevel);
        }
    }

    /**
     * Helper methods for managing JFR CompilerInlining events. The events are defined in {see @code
     * src/share/jfr/metadata/metadata.xml}.
     */
    public static final class CompilerInliningEvent {

        /**
         * Commits a CompilerInlining event.
         *
         * @param compileId current compilation unit id
         * @param caller caller method
         * @param callee callee method
         * @param succeeded inlining succeeded or not
         * @param message extra information on inlining
         * @param bci invocation byte code index
         */

Configuration enabled
profiling false
default false

Field Type Description
compileId uint Compilation Identifier
caller Method Caller Method
callee CalleeMethod struct Callee Method
succeeded boolean Succeeded
message string Message
bci int Bytecode Index

Examples 3
bci int
1
callee CalleeMethod
descriptor string
()V
name string
<init>
type string
scala/collection/mutable/AbstractSeq
caller Method
descriptor string
()V
hidden boolean
false
modifiers int
1
name string
<init>
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
21.0.9
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection/mutable
compileId uint
72189
message string
inline (hot)
startTime long: millis
374323549944
succeeded boolean
true
bci int
1
callee CalleeMethod
descriptor string
()V
name string
<init>
type string
java/lang/Object
caller Method
descriptor string
(II)V
hidden boolean
true
modifiers int
2
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
true
modifiers int
4112
name string
java.util.regex.Pattern$$Lambda/0x00007f30726e0468
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
21.0.9
name string
java/util/regex
compileId uint
73536
message string
inline (hot)
startTime long: millis
366724608114
succeeded boolean
true
bci int
10
callee CalleeMethod
descriptor string
(Z)Lscala/runtime/BooleanRef;
name string
create
type string
scala/runtime/BooleanRef
caller Method
descriptor string
(Lorg/apache/spark/scheduler/TaskSetManager;Lscala/Enumeration$Value;Lscala/collection/immutable/Seq;[I[Lscala/collection/immutable/Map;Lscala/collection/immutable/IndexedSeq;)Lscala/Tuple2;
hidden boolean
false
modifiers int
2
name string
resourceOfferSingleTaskSet
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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/scheduler/TaskSchedulerImpl
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/scheduler
compileId uint
73380
message string
inline
startTime long: millis
278182638450
succeeded boolean
true

Deoptimization

profiling default startTime eventThread stackTrace 14 17 21 25 26 27

Category: Java Virtual Machine / Compiler

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(CompiledMethod* nm,
                                      const Method* method,
                                      int trap_bci,
                                      int instruction,
                                      Deoptimization::DeoptReason reason,
                                      Deoptimization::DeoptAction action) {
  assert(nm != NULL, "invariant");
  assert(method != NULL, "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();
  }
}

Configuration enabled stackTrace
profiling true true
default true false

Field Type Description
compileId uint 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
action DeoptimizationAction
maybe_recompile
bci int
248
compileId uint
77042
compiler CompilerType
c2
instruction Bytecode
if_icmpge
lineNumber int
4588
method Method
descriptor string
(Ljava/util/Formatter;Ljava/lang/StringBuilder;Ljava/lang/CharSequence;IIILjava/util/Locale;)Ljava/lang/StringBuilder;
hidden boolean
false
modifiers int
2
name string
localizedMagnitude
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
8
name string
java/util/Formatter$FormatSpecifier
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
java/util
reason DeoptimizationReason
profile_predicate
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
248
lineNumber int
4588
method Method
descriptor string
(Ljava/util/Formatter;Ljava/lang/StringBuilder;Ljava/lang/CharSequence;IIILjava/util/Locale;)Ljava/lang/StringBuilder;
hidden boolean
false
modifiers int
2
name string
localizedMagnitude
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
8
name string
java/util/Formatter$FormatSpecifier
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
21.0.9
name string
java/util
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
439110844611
action DeoptimizationAction
reinterpret
bci int
108
compileId uint
76996
compiler CompilerType
c2
instruction Bytecode
ifne
lineNumber int
187
method Method
descriptor string
(Lscala/concurrent/stm/ccstm/TxnLevelImpl;Ljava/lang/Object;)V
hidden boolean
false
modifiers int
1
name string
awaitCompleted
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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
1
name string
scala/concurrent/stm/ccstm/TxnLevelImpl
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
scala/concurrent/stm/ccstm
reason DeoptimizationReason
unstable_if
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
108
lineNumber int
187
method Method
descriptor string
(Lscala/concurrent/stm/ccstm/TxnLevelImpl;Ljava/lang/Object;)V
hidden boolean
false
modifiers int
1
name string
awaitCompleted
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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
1
name string
scala/concurrent/stm/ccstm/TxnLevelImpl
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
scala/concurrent/stm/ccstm
type FrameType
Inlined
truncated boolean
false
startTime long: millis
320492874594
action DeoptimizationAction
maybe_recompile
bci int
6
compileId uint
72842
compiler CompilerType
c2
instruction Bytecode
instanceof
lineNumber int
618
method Method
descriptor string
(Ljava/lang/Object;)Z
hidden boolean
false
modifiers int
1
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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
17
name string
scala/Some
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
scala
reason DeoptimizationReason
class_check
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
6
lineNumber int
618
method Method
descriptor string
(Ljava/lang/Object;)Z
hidden boolean
false
modifiers int
1
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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
17
name string
scala/Some
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
scala
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
431956992491

CompilerStatistics

profiling default startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / 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/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());

Configuration enabled period
profiling true 1000 ms
default true 1000 ms

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
bailoutCount int
12
compileCount int
72486
invalidatedCount int
0
nmethodCodeSize ulong: bytes
102578944
nmethodsSize ulong: bytes
149051072
osrBytesCompiled ulong: bytes
0
osrCompileCount int
869
peakTimeSpent long: millis
5268
standardBytesCompiled ulong: bytes
0
standardCompileCount int
71617
startTime long: millis
286626940987
totalTimeSpent long: millis
298504
bailoutCount int
14
compileCount int
105368
invalidatedCount int
0
nmethodCodeSize ulong: bytes
145215088
nmethodsSize ulong: bytes
215397496
osrBytesCompiled ulong: bytes
0
osrCompileCount int
1053
peakTimeSpent long: millis
12707
standardBytesCompiled ulong: bytes
0
standardCompileCount int
104315
startTime long: millis
476030718739
totalTimeSpent long: millis
791587
bailoutCount int
16
compileCount int
104886
invalidatedCount int
0
nmethodCodeSize ulong: bytes
147092072
nmethodsSize ulong: bytes
219116432
osrBytesCompiled ulong: bytes
0
osrCompileCount int
994
peakTimeSpent long: millis
10482
standardBytesCompiled ulong: bytes
0
standardCompileCount int
103892
startTime long: millis
492629230066
totalTimeSpent long: millis
702045

CompilerConfiguration

profiling default startTime end of every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / 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/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(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)) {

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
threadCount int Thread Count
tieredCompilation boolean Tiered Compilation
dynamicCompilerThreadCount boolean 20+ Uses Dynamic Number of Compiler Threads

Examples 3
dynamicCompilerThreadCount boolean
true
startTime long: millis
398111942325
threadCount int
3
tieredCompilation boolean
true
dynamicCompilerThreadCount boolean
true
startTime long: millis
392343878619
threadCount int
3
tieredCompilation boolean
true
dynamicCompilerThreadCount boolean
true
startTime long: millis
299777030010
threadCount int
3
tieredCompilation boolean
true

JVM: Diagnostics

SyncOnValueBasedClass

experimental profiling default startTime eventThread stackTrace 16 17 21 25 26 27

Category: Java Virtual Machine / Diagnostics

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(current);
    Log(valuebasedclasses) vblog;

    vblog.info("Synchronizing on object " INTPTR_FORMAT " of klass %s", p2i(obj()), obj->klass()->external_name());
    if (current->has_last_Java_frame()) {
      LogStream info_stream(vblog.info());
      current->print_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);
  }
}

Configuration enabled stackTrace
profiling true true
default true true

Field Type Description
valueBasedClass Class Value Based Class

HeapDump

profiling default startTime duration eventThread stackTrace 15 17 21 25 26 27

Category: Java Virtual Machine / Diagnostics

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:

  _large_object_list->drain(cl);
}

// dump the heap to given path.
int HeapDumper::dump(const char* path, outputStream* out, int compression, bool overwrite, uint num_dump_threads) {
  assert(path != NULL && strlen(path) > 0, "path missing");

  // print message in interactive case
  if (out != NULL) {
    out->print_cr("Dumping heap to %s ...", path);
    timer()->start();
  }
  // create JFR event
  EventHeapDump event;

  AbstractCompressor* compressor = NULL;

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

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

Configuration enabled stackTrace threshold
profiling true true 0 ns
default true true 0 ns

Field Type Description
destination string Destination
size long Size
gcBeforeDump boolean GC Before Dump
onOutOfMemoryError boolean On Out of Memory Error

JVM: Flag

IntFlagChanged

profiling default startTime 11 17 21 25 26 27

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:

  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 {

Configuration enabled
profiling true
default true

Field Type Description
name string Name
oldValue int Old Value
newValue int New Value
origin FlagValueOrigin Origin

UnsignedIntFlagChanged

profiling default startTime 11 17 21 25 26 27

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, 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 {

Configuration enabled
profiling true
default true

Field Type Description
name string Name
oldValue uint Old Value
newValue uint New Value
origin FlagValueOrigin Origin

LongFlagChanged

profiling default startTime 11 17 21 25 26 27

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=" INTX_FORMAT " is outside the allowed range "
                        "[ " INTX_FORMAT " ... " INTX_FORMAT " ]\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 {

Configuration enabled
profiling true
default true

Field Type Description
name string Name
oldValue long Old Value
newValue long New Value
origin FlagValueOrigin Origin

UnsignedLongFlagChanged

profiling default startTime 11 17 21 25 26 27

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, intx value, bool verbose) const {
    return ((JVMFlagConstraintFunc_intx)func)(value, verbose);
  }
  void print_range_impl(outputStream* st, intx min, intx max) const {
    st->print("[ " INTX_FORMAT_W(-25) " ... " INTX_FORMAT_W(25) " ]", min, max);
  }
  void print_default_range(outputStream* st) const {
    st->print("[ " INTX_FORMAT_W(-25) " ... " INTX_FORMAT_W(25) " ]", 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=" UINTX_FORMAT " is outside the allowed range "
                        "[ " UINTX_FORMAT " ... " UINTX_FORMAT " ]\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("[ " UINTX_FORMAT_W(-25) " ... " UINTX_FORMAT_W(25) " ]", min, max);
  }
  void print_default_range(outputStream* st) const {
    st->print("[ " UINTX_FORMAT_W(-25) " ... " UINTX_FORMAT_W(25) " ]", 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=" SIZE_FORMAT " is outside the allowed range "
                        "[ " SIZE_FORMAT " ... " SIZE_FORMAT " ]\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 {

Configuration enabled
profiling true
default true

Field Type Description
name string Name
oldValue ulong Old Value
newValue ulong New Value
origin FlagValueOrigin Origin

DoubleFlagChanged

profiling default startTime 11 17 21 25 26 27

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, 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("[ " SIZE_FORMAT_W(-25) " ... " SIZE_FORMAT_W(25) " ]", min, max);
  }
  void print_default_range(outputStream* st) const {
    st->print("[ " SIZE_FORMAT_W(-25) " ... " SIZE_FORMAT_W(25) " ]", 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 {

Configuration enabled
profiling true
default true

Field Type Description
name string Name
oldValue double Old Value
newValue double New Value
origin FlagValueOrigin Origin

BooleanFlagChanged

profiling default startTime 11 17 21 25 26 27

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:

    *((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:

Configuration enabled
profiling true
default true

Field Type Description
name string Name
oldValue boolean Old Value
newValue boolean New Value
origin FlagValueOrigin Origin

StringFlagChanged

profiling default startTime 11 17 21 25 26 27

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:

JVMFlag::Error JVMFlagAccess::set_impl(JVMFlag* flag, void* value, JVMFlagOrigin origin) {
  if (flag->is_ccstr()) {
    return set_ccstr(flag, (ccstr*)value, origin);
  } else {
    return access_impl(flag)->set(flag, value, origin);
  }
}

JVMFlag::Error JVMFlagAccess::set_ccstr(JVMFlag* flag, ccstr* value, JVMFlagOrigin origin) {
  if (flag == NULL) return JVMFlag::INVALID_FLAG;
  if (!flag->is_ccstr()) return JVMFlag::WRONG_FORMAT;
  ccstr old_value = flag->get_ccstr();
  trace_flag_changed<ccstr, EventStringFlagChanged>(flag, old_value, *value, origin);
  char* new_value = NULL;
  if (*value != NULL) {
    new_value = os::strdup_check_oom(*value);
  }
  flag->set_ccstr(new_value);
  if (!flag->is_default() && old_value != NULL) {
    // Old value is heap allocated so free it.
    FREE_C_HEAP_ARRAY(char, old_value);
  }
  // Unlike the other APIs, the old vale is NOT returned, so the caller won't need to free it.
  // The callers typically don't care what the old value is.

Configuration enabled
profiling true
default true

Field Type Description
name string Name
oldValue string Old Value
newValue string New Value
origin FlagValueOrigin Origin

IntFlag

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
name string Name
value int Value
origin FlagValueOrigin Origin

Examples 3
name string
DeoptimizeObjectsALotThreadCountSingle
origin FlagValueOrigin
Default
startTime long: millis
280663475659
value int
1
name string
JavaPriority9_To_OSPriority
origin FlagValueOrigin
Default
startTime long: millis
380799189202
value int
-1
name string
UseAVX
origin FlagValueOrigin
Default
startTime long: millis
388177888333
value int
2

UnsignedIntFlag

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
name string Name
value uint Value
origin FlagValueOrigin Origin

Examples 3
name string
TrimNativeHeapInterval
origin FlagValueOrigin
Default
startTime long: millis
293412538582
value uint
0
name string
SharedSymbolTableBucketSize
origin FlagValueOrigin
Default
startTime long: millis
398111957222
value uint
4
name string
ConcGCThreads
origin FlagValueOrigin
Default
startTime long: millis
378913110630
value uint
0

LongFlag

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
name string Name
value long Value
origin FlagValueOrigin Origin

Examples 3
name string
OptoPeepholeAt
origin FlagValueOrigin
Default
startTime long: millis
371363181226
value long
-1
name string
ValueMapInitialSize
origin FlagValueOrigin
Default
startTime long: millis
378913112142
value long
11
name string
PrintIdealGraphPort
origin FlagValueOrigin
Default
startTime long: millis
278185500453
value long
4444

UnsignedLongFlag

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
name string Name
value ulong Value
origin FlagValueOrigin Origin

Examples 3
name string
MaxGCPauseMillis
origin FlagValueOrigin
Default
startTime long: millis
371363219957
value ulong
-2
name string
GCOverheadLimitThreshold
origin FlagValueOrigin
Default
startTime long: millis
378913155503
value ulong
5
name string
AdaptiveSizeMajorGCDecayTimeScale
origin FlagValueOrigin
Default
startTime long: millis
278185538033
value ulong
10

DoubleFlag

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
name string Name
value double Value
origin FlagValueOrigin Origin

Examples 3
name string
EscapeAnalysisTimeout
origin FlagValueOrigin
Default
startTime long: millis
388177974373
value double
20.0
name string
InitialRAMPercentage
origin FlagValueOrigin
Default
startTime long: millis
386025281820
value double
1.5625
name string
G1PeriodicGCSystemLoadThreshold
origin FlagValueOrigin
Default
startTime long: millis
299777117904
value double
0.0

BooleanFlag

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
name string Name
value boolean Value
origin FlagValueOrigin Origin

Examples 3
name string
StressLinearScan
origin FlagValueOrigin
Default
startTime long: millis
378913183405
value boolean
false
name string
VerifyActivationFrameSize
origin FlagValueOrigin
Default
startTime long: millis
371363297702
value boolean
false
name string
UseGCOverheadLimit
origin FlagValueOrigin
Default
startTime long: millis
278185631016
value boolean
true

StringFlag

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
name string Name
value string Value
origin FlagValueOrigin Origin

Examples 3
name string
MallocTraceDumpFilter
origin FlagValueOrigin
Default
startTime long: millis
280663623555
value string
name string
ShenandoahGCMode
origin FlagValueOrigin
Default
startTime long: millis
371363322417
value string
satb
name string
CompileOnly
origin FlagValueOrigin
Default
startTime long: millis
388178057208
value string

JVM: GC: Collector

GarbageCollection

profiling default startTime duration 11 17 21 25 26 27 graal vm

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();
  }
}

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

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
cause GCCause
Allocation Failure
gcId uint
468
longestPause Tickspan
6934342
name GCName
ParallelScavenge
startTime long: millis
457789064234
sumOfPauses Tickspan
6934342
cause GCCause
Heap Inspection Initiated GC
gcId uint
985
longestPause Tickspan
153515175
name GCName
G1Full
startTime long: millis
299777344055
sumOfPauses Tickspan
153515175
cause GCCause
Heap Inspection Initiated GC
gcId uint
879
longestPause Tickspan
323520819
name GCName
SerialOld
startTime long: millis
389981907751
sumOfPauses Tickspan
323520819

SystemGC

profiling default startTime duration eventThread stackTrace 17 21 25 26 27

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

Configuration enabled stackTrace threshold
profiling true true 0 ms
default true true 0 ms

Field Type Description
invokedConcurrent boolean Invoked Concurrent

Examples 3
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
1
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
21.0.9
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
315399538043
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
1
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
21.0.9
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
433417538322
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
1
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
21.0.9
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
442870947343

ParallelOldGarbageCollection

profiling default startTime duration 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Collector

Appearing in: ParallelGC

Missing in: G1GC, SerialGC, ShenandoahGC, 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);

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
densePrefix ulong: address Dense Prefix The address of the dense prefix, used when compacting

Examples 1
densePrefix ulong: address
30368333824
gcId uint
429
startTime long: millis
429098138607

YoungGarbageCollection

profiling default startTime duration 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Collector

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, 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();

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
tenuringThreshold uint Tenuring Threshold

Examples 3
gcId uint
1038
startTime long: millis
326306289318
tenuringThreshold uint
15
gcId uint
896
startTime long: millis
439618977178
tenuringThreshold uint
15
gcId uint
444
startTime long: millis
442193751858
tenuringThreshold uint
15

OldGarbageCollection

profiling default startTime duration 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Collector

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, 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());

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier

Examples 3
gcId uint
995
startTime long: millis
477931538675
gcId uint
423
startTime long: millis
416744016974
gcId uint
976
startTime long: millis
293382302263

G1GarbageCollection

profiling default startTime duration 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Collector

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, 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:

  send_adaptive_ihop_statistics(threshold,
                                internal_target_occupancy,
                                current_occupancy,
                                additional_buffer_size,
                                predicted_allocation_rate,
                                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.
  G1GCPauseTypeHelper::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;

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
type G1YCType Type

Examples 1
gcId uint
1065
startTime long: millis
337760548735
type G1YCType
Concurrent Start

JVM: GC: Configuration

GCConfiguration

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Configuration

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(conf.gc_time_ratio());
  event.set_pauseTarget((s8)pause_target);
  event.commit();
}

Configuration enabled period
profiling true everyChunk
default true everyChunk

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
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
345781239468
usesDynamicGCThreads boolean
true
youngCollector GCName
G1New
concurrentGCThreads uint
0
gcTimeRatio uint
99
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
SerialOld
parallelGCThreads uint
0
pauseTarget long: millis
-9223372036854775808
startTime long: millis
379226110289
usesDynamicGCThreads boolean
true
youngCollector GCName
DefNew
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
467801451074
usesDynamicGCThreads boolean
true
youngCollector GCName
ParallelScavenge

GCSurvivorConfiguration

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Configuration

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(conf.max_tenuring_threshold());
  event.set_initialTenuringThreshold(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());

Configuration enabled period
profiling true beginChunk
default true beginChunk

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
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
461369522245
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
478394377386
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
334950417661

GCTLABConfiguration

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Configuration

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(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(conf.max_tenuring_threshold());
  event.set_initialTenuringThreshold(conf.initial_tenuring_threshold());

Configuration enabled period
profiling true beginChunk
default true beginChunk

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
minTLABSize ulong: bytes
2048
startTime long: millis
349262823719
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
minTLABSize ulong: bytes
2048
startTime long: millis
428614576850
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
minTLABSize ulong: bytes
2048
startTime long: millis
390507144523
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true

GCHeapConfiguration

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Configuration

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(conf.max_tenuring_threshold());
  event.set_initialTenuringThreshold(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(conf.heap_address_size_in_bits());
  event.commit();
}

TRACE_REQUEST_FUNC(YoungGenerationConfiguration) {

Configuration enabled period
profiling true beginChunk
default true beginChunk

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
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
262144000
maxSize ulong: bytes
4194304000
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
293582193700
usesCompressedOops boolean
true
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
262144000
maxSize ulong: bytes
4194304000
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
390507145224
usesCompressedOops boolean
true
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
262144000
maxSize ulong: bytes
4194304000
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
483479824311
usesCompressedOops boolean
true

YoungGenerationConfiguration

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Configuration

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(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(conf.new_ratio());
  event.commit();
}

TRACE_REQUEST_FUNC(InitialSystemProperty) {
  SystemProperty* p = Arguments::system_properties();
  JfrTicks time_stamp = JfrTicks::now();
  while (p !=  NULL) {
    if (!p->internal()) {

Configuration enabled period
profiling true beginChunk
default true beginChunk

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
maxSize ulong: bytes
1398079488
minSize ulong: bytes
87359488
newRatio uint
2
startTime long: millis
461105560481
maxSize ulong: bytes
2516582400
minSize ulong: bytes
1363144
newRatio uint
2
startTime long: millis
286626497451
maxSize ulong: bytes
1397751808
minSize ulong: bytes
87031808
newRatio uint
2
startTime long: millis
443487068032

JVM: GC: Detailed

ZThreadDebug

internal startTime duration eventThread 18 21 25 26 27

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.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::tracer()->report_thread_debug(_name, _start, Ticks::now());
}

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();
  }
}

Field Type Description
gcId uint GC Identifier
name string Name The name of the GC runner

G1MMU

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, 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();
  }
}

Configuration enabled
profiling true
default true

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 1
gcId uint
945
gcTime long: millis
47
pauseTarget long: millis
200
startTime long: millis
278997695746
timeSlice long: millis
201

EvacuationInformation

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, 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:

  G1GCPauseTypeHelper::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->collectionset_regions());
    e.set_cSetUsedBefore(info->collectionset_used_before());
    e.set_cSetUsedAfter(info->collectionset_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();

Configuration enabled
profiling true
default true

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 1
allocationRegions uint
16
allocationRegionsUsedAfter ulong: bytes
31868352
allocationRegionsUsedBefore ulong: bytes
424216
bytesCopied ulong: bytes
31444136
cSetRegions uint
26
cSetUsedAfter ulong: bytes
0
cSetUsedBefore ulong: bytes
53372616
gcId uint
1047
regionsFreed uint
26
startTime long: millis
329919329301

ObjectCountAfterGC

startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, 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;
}

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

Configuration enabled
profiling false
default false

Field Type Description
gcId uint GC Identifier
objectClass Class Object Class
count long Count
totalSize ulong: bytes Total Size

Examples 3
count long
379165
gcId uint
403
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
21.0.9
name string
java/lang
startTime long: millis
383295230229
totalSize ulong: bytes
9099960
count long
398769
gcId uint
943
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
startTime long: millis
278294395695
totalSize ulong: bytes
65283048
count long
45443
gcId uint
880
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
8
name string
java/util/LinkedHashMap$Entry
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
21.0.9
name string
java/util
startTime long: millis
392550854199
totalSize ulong: bytes
1817720

G1EvacuationYoungStatistics

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, 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();

Configuration enabled
profiling true
default true

Field Type Description
statistics G1EvacuationStatistics struct Evacuation Statistics

Examples 1
startTime long: millis
361741855407
statistics G1EvacuationStatistics
allocated ulong: bytes
3251312
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1096
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
2
undoWaste ulong: bytes
0
used ulong: bytes
2147904
wasted ulong: bytes
96

G1EvacuationOldStatistics

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, 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 current_occupancy,
                                             size_t last_allocation_size,
                                             double last_allocation_duration,

Configuration enabled
profiling true
default true

Field Type Description
statistics G1EvacuationStatistics struct Evacuation Statistics

Examples 1
startTime long: millis
293585977954
statistics G1EvacuationStatistics
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
978
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

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, 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:

  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 current_occupancy,
                                             size_t last_allocation_size,
                                             double last_allocation_duration,
                                             double last_marking_length) {
  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(current_occupancy);
    evt.set_recentMutatorAllocationSize(last_allocation_size);
    evt.set_recentMutatorDuration(last_allocation_duration * MILLIUNITS);
    evt.set_recentAllocationRate(last_allocation_duration != 0.0 ? last_allocation_size / last_allocation_duration : 0.0);
    evt.set_lastMarkingDuration(last_marking_length * MILLIUNITS);
    evt.commit();

Configuration enabled
profiling true
default true

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
recentMutatorAllocationSize ulong: bytes Recent Mutator Allocation Size Mutator allocation during mutator operation in the most recent interval
recentMutatorDuration long: millis Recent Mutator Duration Time the mutator ran in the most recent interval
recentAllocationRate double: bytes-per-second Recent Allocation Rate Allocation rate of the mutator in the most recent interval in bytes/second
lastMarkingDuration long: millis Last Marking Duration Last time from the end of the last concurrent start to the first mixed GC

Examples 1
currentOccupancy ulong: bytes
265935408
gcId uint
1074
lastMarkingDuration long: millis
737
recentAllocationRate double: bytes-per-second
0.0
recentMutatorAllocationSize ulong: bytes
0
recentMutatorDuration long: millis
235
startTime long: millis
339988641045
targetOccupancy ulong: bytes
859832320
threshold ulong: bytes
0
thresholdPercentage float: percentage
0.0

G1AdaptiveIHOP

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, 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:

    evt.set_recentAllocationRate(last_allocation_duration != 0.0 ? last_allocation_size / last_allocation_duration : 0.0);
    evt.set_lastMarkingDuration(last_marking_length * MILLIUNITS);
    evt.commit();
  }
}

void G1NewTracer::send_adaptive_ihop_statistics(size_t threshold,
                                                size_t internal_target_occupancy,
                                                size_t current_occupancy,
                                                size_t additional_buffer_size,
                                                double predicted_allocation_rate,
                                                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_predictedAllocationRate(predicted_allocation_rate);
    evt.set_predictedMarkingDuration(predicted_marking_length * MILLIUNITS);
    evt.set_predictionActive(prediction_active);
    evt.commit();

Configuration enabled
profiling true
default true

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
additionalBufferSize ulong: bytes Additional Buffer Additional buffer size
predictedAllocationRate double: bytes-per-second Predicted Allocation Rate Current predicted allocation rate for the mutator in bytes/second
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 1
additionalBufferSize ulong: bytes
471859200
currentOccupancy ulong: bytes
289797144
gcId uint
983
ihopTargetOccupancy ulong: bytes
936378368
predictedAllocationRate double: bytes-per-second
3.461737356160282E8
predictedMarkingDuration long: millis
1379
predictionActive boolean
true
startTime long: millis
299750113367
threshold ulong: bytes
0
thresholdPercentage float: percentage
0.0

PromoteObjectInNewPLAB

profiling startTime eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC

Missing in: SerialGC, ShenandoahGC, 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();
  }
}

Configuration enabled
profiling true
default false

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 2
gcId uint
941
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1040
name string
[Ljava/lang/ThreadLocal$ThreadLocalMap$Entry;
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
21.0.9
name string
java/lang
objectSize ulong: bytes
272
plabSize ulong: bytes
38096
startTime long: millis
278158348759
tenured boolean
false
tenuringAge uint
0
gcId uint
394
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[F
package Package
null
objectSize ulong: bytes
56
plabSize ulong: bytes
32752
startTime long: millis
371365220983
tenured boolean
false
tenuringAge uint
0

PromoteObjectOutsidePLAB

profiling startTime eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC

Missing in: SerialGC, ShenandoahGC, 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 {

Configuration enabled
profiling true
default false

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 2
gcId uint
954
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
21.0.9
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
21.0.9
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
282310506745
tenured boolean
false
tenuringAge uint
0
gcId uint
412
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
32784
startTime long: millis
393081029430
tenured boolean
false
tenuringAge uint
0

PromotionFailed

profiling default startTime 11 17 21 25 26 27

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;

Configuration enabled
profiling true
default true

Field Type Description
gcId uint GC Identifier
promotionFailed CopyFailed struct Promotion Failed Data
thread Thread Running thread

EvacuationFailed

profiling default startTime 11 17 21 25 26 27

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->collectionset_regions());
    e.set_cSetUsedBefore(info->collectionset_used_before());
    e.set_cSetUsedAfter(info->collectionset_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();

Configuration enabled
profiling true
default true

Field Type Description
gcId uint GC Identifier
evacuationFailed CopyFailed struct Evacuation Failed Data

ConcurrentModeFailure

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, 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());

Configuration enabled
profiling true
default true

Field Type Description
gcId uint GC Identifier

Examples 1
gcId uint
1052
startTime long: millis
331300549971

GCCPUTime

profiling default startTime 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, 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;

Configuration enabled
profiling true
default true

Field Type Description
gcId uint GC Identifier
userTime ulong: nanos User Time
systemTime ulong: nanos System Time
realTime ulong: nanos Real Time

Examples 3
gcId uint
489
realTime ulong: nanos
190000000
startTime long: millis
472862858924
systemTime ulong: nanos
0
userTime ulong: nanos
690000000
gcId uint
950
realTime ulong: nanos
9999999
startTime long: millis
282050566136
systemTime ulong: nanos
0
userTime ulong: nanos
9999999
gcId uint
932
realTime ulong: nanos
0
startTime long: millis
451447161068
systemTime ulong: nanos
0
userTime ulong: nanos
9999999

AllocationRequiringGC

startTime eventThread stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, 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();
  }
}

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
gcId uint Pending GC Identifier
size ulong: bytes Allocation Size

Examples 3
gcId uint
937
size ulong: bytes
32
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
778
lineNumber int
2052
method Method
descriptor string
(Ljava/lang/String;)Ljdk/internal/math/FloatingDecimal$ASCIIToBinaryConverter;
hidden boolean
false
modifiers int
8
name string
readJavaFormatString
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
jdk/internal/math/FloatingDecimal
package Package
exported boolean
false
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
jdk/internal/math
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
451792878201
gcId uint
435
size ulong: bytes
24
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
10
lineNumber int
3863
method Method
descriptor string
([BII)[B
hidden boolean
false
modifiers int
10
name string
copyOfRangeByte
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
21.0.9
name string
java/util
type FrameType
Inlined
truncated boolean
true
startTime long: millis
434403190683
gcId uint
1098
size ulong: bytes
1048576
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
155
lineNumber int
243
method Method
descriptor string
(Lio/netty/channel/ChannelHandlerContext;Ljava/lang/Object;)V
hidden boolean
false
modifiers int
1
name string
userEventTriggered
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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
17
name string
io/netty/handler/codec/http2/Http2MultiplexHandler
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/handler/codec/http2
type FrameType
Inlined
truncated boolean
false
startTime long: millis
364403895933

TenuringDistribution

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, SerialGC

Missing in: ParallelGC, ShenandoahGC, 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();
}

Configuration enabled
profiling true
default true

Field Type Description
gcId uint GC Identifier
age uint Age
size ulong: bytes Size

Examples 2
age uint
10
gcId uint
896
size ulong: bytes
0
startTime long: millis
439624775571
age uint
10
gcId uint
941
size ulong: bytes
0
startTime long: millis
278162115827

G1HeapRegionTypeChange

startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, 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/heapRegionTracer.cpp:

void HeapRegionTracer::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();
  }
}

Configuration enabled
profiling false
default false

Field Type Description
index uint Index
from G1HeapRegionType From
to G1HeapRegionType To
start ulong: address Start
used ulong: bytes Used

Examples 1
from G1HeapRegionType
Free
index uint
146
start ulong: address
30471618560
startTime long: millis
278331333837
to G1HeapRegionType
Free
used ulong: bytes
0

ObjectCount

startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, 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

Configuration enabled period
profiling false everyChunk
default false everyChunk

Field Type Description
gcId uint GC Identifier
objectClass Class Object Class
count long Count
totalSize ulong: bytes Total Size

Examples 3
count long
399079
gcId uint
949
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
startTime long: millis
280780051500
totalSize ulong: bytes
65300312
count long
390476
gcId uint
403
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
startTime long: millis
383295230229
totalSize ulong: bytes
64822496
count long
81601
gcId uint
877
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
8
name string
java/util/HashMap$Node
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
21.0.9
name string
java/util
startTime long: millis
382574691462
totalSize ulong: bytes
2611232

G1HeapRegionInformation

startTime duration every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, 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 HeapRegionClosure {
public:
  bool do_heap_region(HeapRegion* 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;

Configuration enabled period
profiling false everyChunk
default false everyChunk

Field Type Description
index uint Index
type G1HeapRegionType Type
start ulong: address Start
used ulong: bytes Used

Examples 1
index uint
441
start ulong: address
31090278400
startTime long: millis
278345517355
type G1HeapRegionType
Free
used ulong: bytes
0

ZAllocationStall

profiling default startTime duration eventThread 15 17 21 25 26 27

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:

  // Success
  return true;
}

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

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

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

  // Increment stalled counter
  Atomic::inc(&_nstalled);

  do {
    // Start asynchronous GC
    ZCollectedHeap::heap()->collect(GCCause::_z_allocation_stall);

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
type ZPageTypeType Type
size ulong: bytes Size

ZPageAllocation

profiling default startTime duration eventThread stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, 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:

    free_page_inner(page, false /* reclaimed */);
  }

  // Adjust capacity and used to reflect the failed capacity increase
  const size_t remaining = allocation->size() - freed;
  decrease_used(remaining, false /* reclaimed */);
  decrease_capacity(remaining, true /* set_max_capacity */);

  // Try satisfy stalled allocations
  satisfy_stalled();
}

ZPage* ZPageAllocator::alloc_page(uint8_t type, size_t size, ZAllocationFlags flags) {
  EventZPageAllocation event;

retry:
  ZPageAllocation allocation(type, size, flags);

  // Allocate one or more pages from the page cache. If the allocation
  // succeeds but the returned pages don't cover the complete allocation,
  // then finalize phase is allowed to allocate the remaining memory
  // directly from the physical memory manager. Note that this call might
  // block in a safepoint if the non-blocking flag is not set.
  if (!alloc_page_or_stall(&allocation)) {
    // Out of memory

Configuration enabled stackTrace threshold
profiling true true 15+ 1 ms
default true true 15+ 1 ms

Field Type Description
type ZPageTypeType 15+ Type
size ulong: bytes 15+ Size
flushed ulong: bytes 17 21 until JDK 25 Flushed
committed ulong: bytes 15+ Committed
segments uint 17 21 until JDK 25 Segments
nonBlocking boolean Non-blocking

Examples 1
committed ulong: bytes
0
flushed ulong: bytes
0
nonBlocking boolean
false
segments uint
1
size ulong: bytes
2097152
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
175
lineNumber int
1425
method Method
descriptor string
(Ljava/lang/Class;I)V
hidden boolean
false
modifiers int
2
name string
filterCheck
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/ObjectInputStream
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
21.0.9
name string
java/io
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
417811131089
type ZPageTypeType
Small

ZRelocationSet

profiling default startTime duration eventThread 15 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, 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() :
    _small("Small", ZPageTypeSmall, ZPageSizeSmall, ZObjectSizeLimitSmall),
    _medium("Medium", ZPageTypeMedium, ZPageSizeMedium, ZObjectSizeLimitMedium),
    _large("Large", ZPageTypeLarge, 0 /* page_size */, 0 /* object_size_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 {

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
total ulong: bytes Total
empty ulong: bytes Empty
relocate ulong: bytes 16+ Relocate

Examples 1
empty ulong: bytes
52428800
relocate ulong: bytes
2982648
startTime long: millis
444956349624
total ulong: bytes
589299712

ZRelocationSetGroup

profiling default startTime duration eventThread 15 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, 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:

  // Update statistics
  _stats._relocate = selected_live_bytes;

  log_trace(gc, reloc)("Relocation Set (%s Pages): %d->%d, %d skipped, " SIZE_FORMAT " 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();
  }

  // Send event
  event.commit(_page_type, _stats.npages(), _stats.total(), _stats.empty(), _stats.relocate());
}

ZRelocationSetSelector::ZRelocationSetSelector() :
    _small("Small", ZPageTypeSmall, ZPageSizeSmall, ZObjectSizeLimitSmall),

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
type ZPageTypeType Type
pages ulong 17 until JDK 21 Pages
total ulong: bytes Total
empty ulong: bytes Empty
relocate ulong: bytes 16+ Relocate

Examples 1
empty ulong: bytes
0
relocate ulong: bytes
11657216
startTime long: millis
453675497693
total ulong: bytes
67108864
type ZPageTypeType
Medium

ZStatisticsCounter

experimental startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, 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.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 ZTracer* ZTracer::tracer() {
  return _tracer;
}

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) {

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

ZTracer::ZTracer() :
    GCTracer(Z) {}

void ZTracer::initialize() {
  assert(_tracer == NULL, "Already initialized");
  _tracer = new ZTracer();
  JFR_ONLY(register_jfr_type_serializers());
}

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

  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;

Configuration enabled threshold
profiling false 0 ms
default false 0 ms

Field Type Description
id ZStatisticsCounterType Id
increment ulong Increment
value ulong Value

Examples 1
id ZStatisticsCounterType
Page Cache Hit L1
increment ulong
1
startTime long: millis
377399311642
value ulong
4

ZStatisticsSampler

experimental startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, 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.inline.hpp:

inline ZTracer* ZTracer::tracer() {
  return _tracer;
}

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) {

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

  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;

  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);

Configuration enabled threshold
profiling false 0 ms
default false 0 ms

Field Type Description
id ZStatisticsSamplerType Id
value ulong Value

Examples 1
id ZStatisticsSamplerType
Page Cache Flush
startTime long: millis
373096062331
value ulong
0

ZThreadPhase

experimental startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, 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.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) :

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

  NoSafepointVerifier nsv;

  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;

Configuration enabled threshold
profiling false 0 ms
default false 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 1
gcId uint
230
name string
Concurrent Classes Purge
startTime long: millis
403416457326

ZUncommit

profiling default startTime duration eventThread 15 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

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::run_service() {
  uint64_t timeout = 0;

  while (wait(timeout)) {
    EventZUncommit event;
    size_t uncommitted = 0;

    while (should_continue()) {
      // Uncommit chunk
      const size_t flushed = _page_allocator->uncommit(&timeout);
      if (flushed == 0) {
        // Done
        break;
      }

      uncommitted += flushed;

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
uncommitted ulong: bytes Uncommitted

ZUnmap

profiling default startTime duration eventThread 17 21 until JDK 25

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Unmapping 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/zUnmapper.cpp:

    ZPage* const page = _queue.remove_first();
    if (page != NULL) {
      return page;
    }

    _lock.wait();
  }
}

void ZUnmapper::do_unmap_and_destroy_page(ZPage* page) const {
  EventZUnmap event;
  const size_t unmapped = page->size();

  // Unmap and destroy
  _page_allocator->unmap_page(page);
  _page_allocator->destroy_page(page);

  // Send event
  event.commit(unmapped);
}

void ZUnmapper::unmap_and_destroy_page(ZPage* page) {

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
unmapped ulong: bytes Unmapped

Examples 1
startTime long: millis
454373953921
unmapped ulong: bytes
2097152

ShenandoahHeapRegionStateChange

startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: ShenandoahGC

Missing in: G1GC, ParallelGC, SerialGC, 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)) {
    report_java_out_of_memory("Unable to uncommit region");
  }
  if (!heap->uncommit_bitmap_slice(this)) {
    report_java_out_of_memory("Unable to uncommit bitmaps for region");
  }
  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 = to;
}

Configuration enabled
profiling false
default false

Field Type Description
index uint Index
from ShenandoahHeapRegionState From
to ShenandoahHeapRegionState To
start ulong: address Start
used ulong: bytes Used

Examples 1
from ShenandoahHeapRegionState
Regular
index uint
13
start ulong: address
30180114432
startTime long: millis
294669009207
to ShenandoahHeapRegionState
Trash
used ulong: bytes
1048576

ShenandoahHeapRegionInformation

startTime duration every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: ShenandoahGC

Missing in: G1GC, ParallelGC, SerialGC, 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);

Configuration enabled period
profiling false everyChunk
default false everyChunk

Field Type Description
index uint Index
state ShenandoahHeapRegionState State
start ulong: address Start
used ulong: bytes Used

Examples 1
index uint
3904
start ulong: address
34260123648
startTime long: millis
294908968758
state ShenandoahHeapRegionState
Regular
used ulong: bytes
1048576

GCLocker

profiling default startTime eventThread stackTrace 17 21 until JDK 25

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/gcTraceSend.cpp:

Ticks GCLockerTracer::_needs_gc_start_timestamp;
volatile jint GCLockerTracer::_jni_lock_count = 0;
volatile jint GCLockerTracer::_stall_count = 0;

bool GCLockerTracer::is_started() {
  return _needs_gc_start_timestamp != Ticks();
}

void GCLockerTracer::start_gc_locker(const jint jni_lock_count) {
  assert(SafepointSynchronize::is_at_safepoint(), "sanity");
  assert(!is_started(), "sanity");
  assert(_jni_lock_count == 0, "sanity");
  assert(_stall_count == 0, "sanity");
  if (EventGCLocker::is_enabled()) {
    _needs_gc_start_timestamp.stamp();
    _jni_lock_count = jni_lock_count;
  }
}

void GCLockerTracer::inc_stall_count() {
  if (is_started()) {
    _stall_count++;
  }
}

void GCLockerTracer::report_gc_locker() {
  if (is_started()) {
    EventGCLocker event(UNTIMED);
    if (event.should_commit()) {
      event.set_starttime(_needs_gc_start_timestamp);
      event.set_endtime(_needs_gc_start_timestamp);
      event.set_lockCount(_jni_lock_count);
      event.set_stallCount(_stall_count);
      event.commit();
    }
    // reset
    _needs_gc_start_timestamp = Ticks();
    _jni_lock_count = 0;
    _stall_count = 0;

Configuration enabled stackTrace threshold
profiling true true 100 ms
default true true 1 s

Field Type Description
lockCount uint Lock Count The number of Java threads in a critical section when the GC locker is started
stallCount uint Stall Count The number of Java threads stalled by the GC locker

JVM: GC: Heap

GCHeapSummary

profiling default startTime 11 17 21 25 26 27

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);

Configuration enabled
profiling true
default true

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
gcId uint
436
heapSpace VirtualSpace
committedEnd ulong: address
33038008320
committedSize ulong: bytes
2872573952
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4194304000
start ulong: address
30165434368
heapUsed ulong: bytes
209603232
startTime long: millis
434845161599
when GCWhen
After GC
gcId uint
876
heapSpace VirtualSpace
committedEnd ulong: address
31159918592
committedSize ulong: bytes
994484224
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4194304000
start ulong: address
30165434368
heapUsed ulong: bytes
308699808
startTime long: millis
378913407092
when GCWhen
Before GC
gcId uint
984
heapSpace VirtualSpace
committedEnd ulong: address
31151095808
committedSize ulong: bytes
985661440
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4194304000
start ulong: address
30165434368
heapUsed ulong: bytes
289797144
startTime long: millis
299750162476
when GCWhen
Before GC

MetaspaceSummary

profiling default startTime 11 17 21 25 26 27

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:

  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();
  }
}

Configuration enabled
profiling true
default true

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
classSpace MetaspaceSizes
committed ulong: bytes
88080384
reserved ulong: bytes
1073741824
used ulong: bytes
86220248
dataSpace MetaspaceSizes
committed ulong: bytes
570949632
reserved ulong: bytes
603979776
used ulong: bytes
569028544
gcId uint
970
gcThreshold ulong: bytes
1098383360
metaspace MetaspaceSizes
committed ulong: bytes
659030016
reserved ulong: bytes
1677721600
used ulong: bytes
655248792
startTime long: millis
289456761815
when GCWhen
After GC
classSpace MetaspaceSizes
committed ulong: bytes
86507520
reserved ulong: bytes
1073741824
used ulong: bytes
84670096
dataSpace MetaspaceSizes
committed ulong: bytes
560136192
reserved ulong: bytes
603979776
used ulong: bytes
558296096
gcId uint
419
gcThreshold ulong: bytes
1077739520
metaspace MetaspaceSizes
committed ulong: bytes
646643712
reserved ulong: bytes
1677721600
used ulong: bytes
642966192
startTime long: millis
407001863903
when GCWhen
Before GC
classSpace MetaspaceSizes
committed ulong: bytes
90112000
reserved ulong: bytes
1073741824
used ulong: bytes
88177368
dataSpace MetaspaceSizes
committed ulong: bytes
583729152
reserved ulong: bytes
603979776
used ulong: bytes
581802360
gcId uint
892
gcThreshold ulong: bytes
1099956224
metaspace MetaspaceSizes
committed ulong: bytes
673841152
reserved ulong: bytes
1677721600
used ulong: bytes
669979728
startTime long: millis
432433411389
when GCWhen
After GC

PSHeapSummary

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Heap

Appearing in: ParallelGC

Missing in: G1GC, SerialGC, ShenandoahGC, 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();

Configuration enabled
profiling true
default true

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 1
edenSpace ObjectSpace
end ulong: address
34230239232
size ulong: bytes
1268252672
start ulong: address
32961986560
used ulong: bytes
0
fromSpace ObjectSpace
end ulong: address
34270085120
size ulong: bytes
18350080
start ulong: address
34251735040
used ulong: bytes
0
gcId uint
427
oldObjectSpace ObjectSpace
end ulong: address
31729909760
size ulong: bytes
1564475392
start ulong: address
30165434368
used ulong: bytes
223452200
oldSpace VirtualSpace
committedEnd ulong: address
31729909760
committedSize ulong: bytes
1564475392
reservedEnd ulong: address
32961986560
reservedSize ulong: bytes
2796552192
start ulong: address
30165434368
startTime long: millis
426755847889
toSpace ObjectSpace
end ulong: address
34250162176
size ulong: bytes
19922944
start ulong: address
34230239232
used ulong: bytes
0
when GCWhen
After GC
youngSpace VirtualSpace
committedEnd ulong: address
34270085120
committedSize ulong: bytes
1308098560
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
1397751808
start ulong: address
32961986560

G1HeapSummary

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Heap

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, 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_numberOfRegions(g1_heap_summary->numberOfRegions());
      e.commit();
    }
  }

Configuration enabled
profiling true
default true

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
numberOfRegions uint Number of Regions

Examples 1
edenTotalSize ulong: bytes
492394816
edenUsedSize ulong: bytes
69206016
gcId uint
988
numberOfRegions uint
470
startTime long: millis
301807126388
survivorUsedSize ulong: bytes
435904
when GCWhen
Before GC

JVM: GC: Metaspace

MetaspaceGCThreshold

profiling default startTime 11 17 21 25 26 27

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_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);
}

Configuration enabled
profiling true
default true

Field Type Description
oldValue ulong: bytes Old Value
newValue ulong: bytes New Value
updater GCThresholdUpdater Updater

Examples 3
newValue ulong: bytes
1128136704
oldValue ulong: bytes
1122304000
startTime long: millis
315605077601
updater GCThresholdUpdater
compute_new_size
newValue ulong: bytes
1098973184
oldValue ulong: bytes
1078329344
startTime long: millis
429260631754
updater GCThresholdUpdater
compute_new_size
newValue ulong: bytes
1471217664
oldValue ulong: bytes
1432616960
startTime long: millis
463656292362
updater GCThresholdUpdater
compute_new_size

MetaspaceAllocationFailure

profiling default startTime stackTrace 11 17 21 25 26 27

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,

Configuration enabled stackTrace
profiling true true
default true true

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

profiling default startTime stackTrace 11 17 21 25 26 27

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());

Configuration enabled stackTrace
profiling true true
default true true

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

profiling default startTime 11 17 21 25 26 27

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/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());

Configuration enabled
profiling true
default true

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
gcId uint
409
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
387704493047
when GCWhen
Before GC
gcId uint
885
humongousChunks ulong
0
humongousChunksTotalSize ulong: bytes
0
mediumChunks ulong
0
mediumChunksTotalSize ulong: bytes
0
metadataType MetadataType
Metadata
smallChunks ulong
0
smallChunksTotalSize ulong: bytes
0
specializedChunks ulong
0
specializedChunksTotalSize ulong: bytes
0
startTime long: millis
409662285604
when GCWhen
Before GC
gcId uint
946
humongousChunks ulong
0
humongousChunksTotalSize ulong: bytes
0
mediumChunks ulong
0
mediumChunksTotalSize ulong: bytes
0
metadataType MetadataType
Metadata
smallChunks ulong
0
smallChunksTotalSize ulong: bytes
0
specializedChunks ulong
0
specializedChunksTotalSize ulong: bytes
0
startTime long: millis
279634503120
when GCWhen
Before GC

JVM: GC: Phases

GCPhasePause

profiling default startTime duration eventThread 11 17 21 25 26 27 graal vm

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() < 2, "There is only two levels for ConcurrentPhase");

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
989
name string
GC Pause
startTime long: millis
303893344929
gcId uint
940
name string
GC Pause
startTime long: millis
451979970577
gcId uint
451
name string
GC Pause
startTime long: millis
447848352329

GCPhasePauseLevel1

profiling default startTime duration eventThread 11 17 21 25 26 27 graal vm

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Missing in: 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() < 2, "There is only two levels for ConcurrentPhase");

    switch (phase->level()) {

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
961
name string
Update Remembered Set Tracking Before Rebuild
startTime long: millis
285690584906
gcId uint
408
name string
Scavenge
startTime long: millis
387702208034
gcId uint
896
name string
Notify Soft/WeakReferences
startTime long: millis
439623372236

GCPhasePauseLevel2

profiling default startTime duration eventThread 11 17 21 25 26 27 graal vm

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, 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() < 2, "There is only two levels for ConcurrentPhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhaseConcurrent>(phase); break;

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
882
name string
Class Unloading
startTime long: millis
404765294890
gcId uint
956
name string
Phase 1: Class Unloading and Cleanup
startTime long: millis
282905476736
gcId uint
395
name string
Weak Processing
startTime long: millis
371423363519

GCPhasePauseLevel3

startTime duration eventThread 11 17 21 25 26 27 graal vm

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, 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() < 2, "There is only two levels for ConcurrentPhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhaseConcurrent>(phase); break;
      case 1: send_phase<EventGCPhaseConcurrentLevel1>(phase); break;

Configuration enabled threshold
profiling false 0 ms
default false 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
946
name string
Notify PhantomReferences
startTime long: millis
279699079728
gcId uint
403
name string
Notify Soft/WeakReferences
startTime long: millis
383239784020
gcId uint
878
name string
Unregister NMethods
startTime long: millis
388328336259

GCPhasePauseLevel4

startTime duration eventThread 11 17 21 25 26 27 graal vm

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ParallelGC

Missing in: SerialGC, ShenandoahGC, 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() < 2, "There is only two levels for ConcurrentPhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhaseConcurrent>(phase); break;
      case 1: send_phase<EventGCPhaseConcurrentLevel1>(phase); break;
      default: /* Ignore sending this phase */ break;

Configuration enabled threshold
profiling false 0 ms
default false 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 2
gcId uint
994
name string
Balance queues
startTime long: millis
304966915198
gcId uint
415
name string
Balance queues
startTime long: millis
398178833512

GCPhaseConcurrent

profiling default startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ShenandoahGC, ZGC

Missing in: ParallelGC, 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() < 2, "There is only two levels for ConcurrentPhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhaseConcurrent>(phase); break;
      case 1: send_phase<EventGCPhaseConcurrentLevel1>(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());

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
970
name string
Concurrent Scan Root Regions
startTime long: millis
289278736059
gcId uint
234
name string
Concurrent Reset Relocation Set
startTime long: millis
431679800957
gcId uint
228
name string
Concurrent Marking
startTime long: millis
305245268513

GCPhaseConcurrentLevel1

profiling default startTime duration eventThread 15 17 21 25 26 27

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ShenandoahGC, ZGC

Missing in: ParallelGC, 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() < 2, "There is only two levels for ConcurrentPhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhaseConcurrent>(phase); break;
      case 1: send_phase<EventGCPhaseConcurrentLevel1>(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());

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
226
name string
ClassLoaderData
startTime long: millis
377366272618
gcId uint
260
name string
Trigger cleanups
startTime long: millis
367844513852
gcId uint
1013
name string
Preclean FinalReferences
startTime long: millis
312375261055

GCPhaseParallel

profiling default startTime duration eventThread 12 17 21 25 26 27

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ShenandoahGC

Missing in: ParallelGC, SerialGC, 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/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();
};

class ShenandoahSuspendibleThreadSetJoiner {
private:
  SuspendibleThreadSetJoiner _joiner;
public:
  ShenandoahSuspendibleThreadSetJoiner(bool active = true) : _joiner(active) {

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/g1/g1RemSet.cpp:

  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:

    _opt_refs_memory_used(0),
    _code_root_scan_time(),
    _code_trim_partially_time(),
    _rem_set_opt_root_scan_time(),
    _rem_set_opt_trim_partially_time() { }

  bool do_heap_region(HeapRegion* r) {
    uint const region_idx = r->hrm_index();

    // The individual references for the optional remembered set are per-worker, so we
    // always need to scan them.
    if (r->has_index_in_opt_cset()) {
      EventGCPhaseParallel event;
      G1EvacPhaseWithTrimTimeTracker timer(_pss, _rem_set_opt_root_scan_time, _rem_set_opt_trim_partially_time);
      scan_opt_rem_set_roots(r);

      event.commit(GCId::current(), _worker_id, G1GCPhaseTimes::phase_name(_scan_phase));
    }

    if (_scan_state->claim_collection_set_region(region_idx)) {
      EventGCPhaseParallel event;
      G1EvacPhaseWithTrimTimeTracker timer(_pss, _code_root_scan_time, _code_trim_partially_time);
      // Scan the code root list attached to the current region
      r->code_roots_do(_pss->closures()->weak_codeblobs());

      event.commit(GCId::current(), _worker_id, G1GCPhaseTimes::phase_name(_code_roots_phase));
    }

    return false;
  }

src/hotspot/share/gc/g1/g1YoungGCPostEvacuateTasks.cpp:

    _before_used_bytes += used;
    _regions_freed += 1;
  }

  void account_rs_length(HeapRegion* r) {
    _rs_length += r->rem_set()->occupied();
  }
};

// Closure applied to all regions in the collection set.
class FreeCSetClosure : public HeapRegionClosure {
  // Helper to send JFR events for regions.
  class JFREventForRegion {
    EventGCPhaseParallel _event;

  public:
    JFREventForRegion(HeapRegion* 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/heapRegionManager.cpp:

      _worker_freelists[worker].~FreeRegionList();
    }
    FREE_C_HEAP_ARRAY(FreeRegionList, _worker_freelists);
  }

  FreeRegionList* 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->reserved_length());

    // If start is outside the heap, this worker has nothing to do.
    if (start > end) {
      return;
    }

    FreeRegionList *free_list = worker_freelist(worker_id);
    for (uint i = start; i < end; i++) {

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/shenandoah/shenandoahPhaseTimings.hpp:

  static const char* phase_name(Phase phase) {
    assert(phase >= 0 && phase < _num_phases, "Out of bound");
    return _phase_names[phase];
  }

  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::ParPhase const _par_phase;
  uint const _worker_id;

  double _start_time;
  EventGCPhaseParallel _event;
public:
  ShenandoahWorkerTimingsTracker(ShenandoahPhaseTimings::Phase phase, ShenandoahPhaseTimings::ParPhase par_phase, uint worker_id);
  ~ShenandoahWorkerTimingsTracker();
};

#endif // SHARE_GC_SHENANDOAH_SHENANDOAHPHASETIMINGS_HPP

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
gcWorkerId uint GC Worker Identifier
name string Name

Examples 2
gcId uint
941
gcWorkerId uint
0
name string
FreeCSet
startTime long: millis
278162007523
gcId uint
235
gcWorkerId uint
0
name string
Finish Mark
startTime long: millis
336443525171

JVM: GC: Reference

GCReferenceStatistics

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Reference

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;

Configuration enabled
profiling true
default true

Field Type Description
gcId uint GC Identifier
type ReferenceType Type
count ulong Total Count

Examples 3
count ulong
2911
gcId uint
884
startTime long: millis
407025133915
type ReferenceType
Weak reference
count ulong
0
gcId uint
966
startTime long: millis
287021259755
type ReferenceType
Phantom reference
count ulong
12564
gcId uint
417
startTime long: millis
400677694159
type ReferenceType
Weak reference

JVM: Internal

Duration

internal startTime duration eventThread 18 21 25 26 27

Category: Java Virtual Machine / Internal

Instant

internal startTime eventThread 18 21 25 26 27

Category: Java Virtual Machine / Internal

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.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/EventProvider.java:

    /**
     * Creates and returns an empty implementation for {@link CompilationEvent}.
     */
    static CompilerFailureEvent createEmptyCompilerFailureEvent() {
        return new EmptyCompilerFailureEvent();
    }

    /**
     * An instant event is an event that is not considered to have taken any time.
     */
    public interface InstantEvent {
        /**
         * Commits the event.
         */
        void commit();

        /**
         * Determines if this particular event instance would be committed to the data stream right
         * now if application called {@link #commit()}. This in turn depends on whether the event is
         * enabled and possible other factors.
         *
         * @return if this event would be committed on a call to {@link #commit()}.
         */
        boolean shouldWrite();
    }

    /**
     * Timed events describe an operation that somehow consumes time.
     */
    public interface TimedEvent extends InstantEvent {
        /**
         * Starts the timing for this event.
         */
        void begin();

        /**
         * Ends the timing period for this event.
         */
        void end();
    }

src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/EventProvider.java:

        void setIsOsr(boolean isOsr);

        void setCodeSize(int codeSize);

        void setInlinedBytes(int inlinedBytes);
    }

    /**
     * Creates a new {@link CompilerFailureEvent}.
     *
     * @return a compiler failure event
     */
    CompilerFailureEvent newCompilerFailureEvent();

    /**
     * A compiler failure event.
     */
    public interface CompilerFailureEvent extends InstantEvent {
        void setCompileId(int compileId);

        void setMessage(String message);
    }
}

Value

internal startTime eventThread 18 21 25 26 27

Category: Java Virtual Machine / Internal

Field Type Description
value ulong Value

Text

internal startTime eventThread 18 21 25 26 27

Category: Java Virtual Machine / Internal

Field Type Description
text string Text

JVM: Memory

NativeMemoryUsage

profiling default startTime duration every chunk 20 21 25 26 27

Category: Java Virtual Machine / Memory

Native memory usage for a given memory type 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/services/memJfrReporter.cpp:

  NMTUsage* usage = MemJFRCurrentUsage::get_usage();
  Ticks timestamp = MemJFRCurrentUsage::get_timestamp();

  EventNativeMemoryUsageTotal event(UNTIMED);
  event.set_starttime(timestamp);
  event.set_reserved(usage->total_reserved());
  event.set_committed(usage->total_committed());
  event.commit();
}

void MemJFRReporter::send_type_event(const Ticks& starttime, const char* type, size_t reserved, size_t committed) {
  EventNativeMemoryUsage event(UNTIMED);
  event.set_starttime(starttime);
  event.set_type(type);
  event.set_reserved(reserved);
  event.set_committed(committed);
  event.commit();
}

void MemJFRReporter::send_type_events() {
  if (!MemTracker::enabled()) {
    return;
  }

Configuration enabled period
profiling true 1000 ms
default true 1000 ms

Field Type Description
type string 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

NativeMemoryUsageTotal

profiling default startTime duration every chunk 20 21 25 26 27

Category: Java Virtual Machine / Memory

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/services/memJfrReporter.cpp:

Ticks MemJFRCurrentUsage::get_timestamp() {
  return _timestamp;
}

void MemJFRReporter::send_total_event() {
  if (!MemTracker::enabled()) {
    return;
  }

  NMTUsage* usage = MemJFRCurrentUsage::get_usage();
  Ticks timestamp = MemJFRCurrentUsage::get_timestamp();

  EventNativeMemoryUsageTotal event(UNTIMED);
  event.set_starttime(timestamp);
  event.set_reserved(usage->total_reserved());
  event.set_committed(usage->total_committed());
  event.commit();
}

void MemJFRReporter::send_type_event(const Ticks& starttime, const char* type, size_t reserved, size_t committed) {
  EventNativeMemoryUsage event(UNTIMED);
  event.set_starttime(starttime);
  event.set_type(type);
  event.set_reserved(reserved);

Configuration enabled period
profiling true 1000 ms
default true 1000 ms

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

JVM: Profiling

OldObjectSample

cutoff profiling default startTime eventThread stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / Profiling

Appearing in: G1GC, ParallelGC, SerialGC, ZGC

Missing in: ShenandoahGC

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/jni/jfrJniMethod.cpp:

NO_TRANSITION(jlong, jfr_elapsed_counter(JNIEnv* env, jobject jvm))
  return JfrTicks::now();
NO_TRANSITION_END

NO_TRANSITION(void, jfr_retransform_classes(JNIEnv* env, jobject 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, jobject jvm, jlong event_type_id, jboolean enabled))
  JfrEventSetting::set_enabled(event_type_id, JNI_TRUE == enabled);
  if (EventOldObjectSample::eventId == event_type_id) {
    ThreadInVMfromNative transition(JavaThread::thread_from_jni_environment(env));
    if (JNI_TRUE == enabled) {
      LeakProfiler::start(JfrOptionSet::old_object_queue_size());
    } else {
      LeakProfiler::stop();
    }
  }
NO_TRANSITION_END

NO_TRANSITION(void, jfr_set_file_notification(JNIEnv* env, jobject jvm, jlong threshold))
  JfrChunkRotation::set_threshold(threshold);

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/leakprofiler/checkpoint/eventEmitter.cpp:

  assert(!sample->is_dead(), "invariant");
  assert(edge_store != NULL, "invariant");
  assert(_jfr_thread_local != NULL, "invariant");

  const StoredEdge* const edge = edge_store->get(sample);
  assert(edge != NULL, "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

Configuration cutoff enabled stackTrace
profiling 0 ns true true
default 0 ns true false

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 -1 if it is not an array
root OldObjectGcRoot GC Root

Examples 3
allocationTime Ticks
298975048632
arrayElements int
32768
lastKnownHeapUsage ulong: bytes
138204656
object OldObject
address ulong: address
31702930736
description string
null
referrer Reference
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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
1041
name string
[Lscala/reflect/internal/Names$TypeName;
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
scala/reflect/internal
objectAge Tickspan
194426656926
objectSize ulong: bytes
131088
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
44
lineNumber int
52
method Method
descriptor string
(Lscala/reflect/internal/Names;)V
hidden boolean
false
modifiers int
9
name string
$init$
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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
1537
name string
scala/reflect/internal/Names
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
scala/reflect/internal
type FrameType
Interpreted
truncated boolean
true
startTime long: millis
493401705558
allocationTime Ticks
343014264425
arrayElements int
519781
lastKnownHeapUsage ulong: bytes
340615552
object OldObject
address ulong: address
30379343872
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
24322427049
objectSize ulong: bytes
519800
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
128
lineNumber int
1678
method Method
descriptor string
(I)V
hidden boolean
false
modifiers int
2
name string
initCEN
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
java/util/zip/ZipFile$Source
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
java/util/zip
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
367336691474
allocationTime Ticks
458059993979
arrayElements int
-2147483648
lastKnownHeapUsage ulong: bytes
233864880
object OldObject
address ulong: address
30399065944
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
8
name string
java/util/concurrent/LinkedBlockingQueue$Node
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
21.0.9
name string
java/util/concurrent
objectAge Tickspan
24384874580
objectSize ulong: bytes
24
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
30
lineNumber int
409
method Method
descriptor string
(Ljava/lang/Object;)Z
hidden boolean
false
modifiers int
1
name string
offer
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/LinkedBlockingQueue
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
21.0.9
name string
java/util/concurrent
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
482444868559

ExecutionSample

profiling default startTime every chunk 11 17 21 25 26 27 graal vm

Category: Java Virtual Machine / Profiling

Snapshot of a threads state

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/jfrThreadSampler.cpp:

    case _thread_in_native_trans:
      break;
    case _thread_in_native:
      return true;
    default:
      ShouldNotReachHere();
      break;
  }
  return false;
}

class JfrThreadSampleClosure {
 public:
  JfrThreadSampleClosure(EventExecutionSample* events, EventNativeMethodSample* events_native);
  ~JfrThreadSampleClosure() {}
  EventExecutionSample* next_event() { return &_events[_added_java++]; }
  EventNativeMethodSample* next_event_native() { return &_events_native[_added_native++]; }
  void commit_events(JfrSampleType type);
  bool do_sample_thread(JavaThread* thread, JfrStackFrame* frames, u4 max_frames, JfrSampleType type);
  uint java_entries() { return _added_java; }
  uint native_entries() { return _added_native; }

 private:
  bool sample_thread_in_java(JavaThread* thread, JfrStackFrame* frames, u4 max_frames);
  bool sample_thread_in_native(JavaThread* thread, JfrStackFrame* frames, u4 max_frames);
  EventExecutionSample* _events;
  EventNativeMethodSample* _events_native;
  Thread* _self;
  uint _added_java;
  uint _added_native;
};

class OSThreadSampler : public SuspendedThreadTask {
 public:
  OSThreadSampler(JavaThread* thread,
                  JfrThreadSampleClosure& closure,
                  JfrStackFrame *frames,

src/hotspot/share/jfr/periodic/sampling/jfrThreadSampler.cpp:

  // Skip sample if we signaled a thread that moved to other state
  if (!thread_state_in_java(jt)) {
    return;
  }
  JfrGetCallTrace trace(true, jt);
  frame topframe;
  if (trace.get_topframe(context.ucontext(), topframe)) {
    if (_stacktrace.record_async(jt, topframe)) {
      /* If we managed to get a topframe and a stacktrace, create an event
      * and put it into our array. We can't call Jfr::_stacktraces.add()
      * here since it would allocate memory using malloc. Doing so while
      * the stopped thread is inside malloc would deadlock. */
      _success = true;
      EventExecutionSample *ev = _closure.next_event();
      ev->set_starttime(_suspend_time);
      ev->set_endtime(_suspend_time); // fake to not take an end time
      ev->set_sampledThread(JfrThreadLocal::thread_id(jt));
      ev->set_state(static_cast<u8>(java_lang_Thread::get_thread_status(_thread_oop)));
    }
  }
}

void OSThreadSampler::take_sample() {
  run();
}

src/hotspot/share/jfr/periodic/sampling/jfrThreadSampler.cpp:

  // skip frames in stack chunks on the Java heap.
  StackWatermarkSet::start_processing(thread, StackWatermarkKind::gc);

  OSThreadSampler sampler(thread, *this, frames, max_frames);
  sampler.take_sample();
  /* We don't want to allocate any memory using malloc/etc while the thread
  * is stopped, so everything is stored in stack allocated memory until this
  * point where the thread has been resumed again, if the sampling was a success
  * we need to store the stacktrace in the stacktrace repository and update
  * the event with the id that was returned. */
  if (!sampler.success()) {
    return false;
  }
  EventExecutionSample *event = &_events[_added_java - 1];
  traceid id = JfrStackTraceRepository::add(sampler.stacktrace());
  assert(id != 0, "Stacktrace id should not be 0");
  event->set_stackTrace(id);
  return true;
}

bool JfrThreadSampleClosure::sample_thread_in_native(JavaThread* thread, JfrStackFrame* frames, u4 max_frames) {
  // Process the oops in the thread head before calling into code that wants to
  // stack walk over Loom continuations. The stack walking code will otherwise
  // skip frames in stack chunks on the Java heap.
  StackWatermarkSet::start_processing(thread, StackWatermarkKind::gc);

src/hotspot/share/jfr/periodic/sampling/jfrThreadSampler.cpp:

  EventNativeMethodSample *event = &_events_native[_added_native - 1];
  traceid id = JfrStackTraceRepository::add(cb.stacktrace());
  assert(id != 0, "Stacktrace id should not be 0");
  event->set_stackTrace(id);
  return true;
}

static const uint MAX_NR_OF_JAVA_SAMPLES = 5;
static const uint MAX_NR_OF_NATIVE_SAMPLES = 1;

void JfrThreadSampleClosure::commit_events(JfrSampleType type) {
  if (JAVA_SAMPLE == type) {
    assert(_added_java > 0 && _added_java <= MAX_NR_OF_JAVA_SAMPLES, "invariant");
    if (EventExecutionSample::is_enabled()) {
      for (uint i = 0; i < _added_java; ++i) {
        _events[i].commit();
      }
    }
  } else {
    assert(NATIVE_SAMPLE == type, "invariant");
    assert(_added_native > 0 && _added_native <= MAX_NR_OF_NATIVE_SAMPLES, "invariant");
    if (EventNativeMethodSample::is_enabled()) {
      for (uint i = 0; i < _added_native; ++i) {
        _events_native[i].commit();
      }
    }
  }
}

JfrThreadSampleClosure::JfrThreadSampleClosure(EventExecutionSample* events, EventNativeMethodSample* events_native) :
  _events(events),
  _events_native(events_native),
  _self(Thread::current()),
  _added_java(0),
  _added_native(0) {
}

class JfrThreadSampler : public NonJavaThread {
  friend class JfrThreadSampling;
 private:
  Semaphore _sample;

src/hotspot/share/jfr/periodic/sampling/jfrThreadSampler.cpp:

const JfrBuffer* JfrThreadSampler::get_enqueue_buffer() {
  const JfrBuffer* buffer = JfrTraceIdLoadBarrier::get_sampler_enqueue_buffer(this);
  return buffer != nullptr ? renew_if_full(buffer) : JfrTraceIdLoadBarrier::renew_sampler_enqueue_buffer(this);
}

const JfrBuffer* JfrThreadSampler::renew_if_full(const JfrBuffer* enqueue_buffer) {
  assert(enqueue_buffer != nullptr, "invariant");
  return enqueue_buffer->free_size() < _min_size ? JfrTraceIdLoadBarrier::renew_sampler_enqueue_buffer(this) : enqueue_buffer;
}

void JfrThreadSampler::task_stacktrace(JfrSampleType type, JavaThread** last_thread) {
  ResourceMark rm;
  EventExecutionSample samples[MAX_NR_OF_JAVA_SAMPLES];
  EventNativeMethodSample samples_native[MAX_NR_OF_NATIVE_SAMPLES];
  JfrThreadSampleClosure sample_task(samples, samples_native);

  const uint sample_limit = JAVA_SAMPLE == type ? MAX_NR_OF_JAVA_SAMPLES : MAX_NR_OF_NATIVE_SAMPLES;
  uint num_samples = 0;
  JavaThread* start = NULL;
  {
    elapsedTimer sample_time;
    sample_time.start();
    {
      MutexLocker tlock(Threads_lock);

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

JVM_ENTRY_NO_ENV(void, jfr_subscribe_log_level(JNIEnv* env, jobject 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, jobject jvm, jstring path))
  JfrRepository::set_chunk_path(path, thread);
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_set_method_sampling_period(JNIEnv* env, jobject 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) {
    JfrThreadSampling::set_java_sample_period(periodMillis);
  } else {
    JfrThreadSampling::set_native_sample_period(periodMillis);
  }
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_store_metadata_descriptor(JNIEnv* env, jobject jvm, jbyteArray descriptor))
  JfrMetadataEvent::update(descriptor);
JVM_END

// trace thread id for a thread object

Configuration enabled period
profiling true 10 ms
default true 20 ms

Field Type Description
sampledThread Thread Thread
stackTrace StackTrace Stack Trace
state ThreadState Thread State

Examples 3
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 18.0 (TID 107)
javaThreadId long
1184
osName string
Executor task launch worker for task 0.0 in stage 18.0 (TID 107)
osThreadId long
3743
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
31
lineNumber int
1019
method Method
descriptor string
()Ljava/lang/Object;
hidden boolean
false
modifiers int
0
name string
newInstance
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/io/ObjectStreamClass
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
21.0.9
name string
java/io
type FrameType
Inlined
truncated boolean
true
startTime long: millis
282050788922
state ThreadState
STATE_RUNNABLE
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 4.0 in stage 18.0 (TID 111)
javaThreadId long
1179
osName string
Executor task launch worker for task 4.0 in stage 18.0 (TID 111)
osThreadId long
4413
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
62
lineNumber int
182
method Method
descriptor string
(I)I
hidden boolean
false
modifiers int
1
name string
getPos$mcI$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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/util/collection/OpenHashSet$mcI$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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/util/collection
type FrameType
Inlined
truncated boolean
true
startTime long: millis
381686892010
state ThreadState
STATE_RUNNABLE
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 5.0 in stage 18.0 (TID 112)
javaThreadId long
1166
osName string
Executor task launch worker for task 5.0 in stage 18.0 (TID 112)
osThreadId long
3757
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
357
lineNumber int
1745
method Method
descriptor string
(IIZLscala/Option;Lorg/apache/spark/ml/recommendation/ALS$LocalIndexEncoder;ZDLorg/apache/spark/ml/recommendation/ALS$LeastSquaresNESolver;DLscala/Tuple2;)[[F
hidden boolean
false
modifiers int
4121
name string
$anonfun$computeFactors$4
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
java/net
hidden boolean
false
modifiers int
17
name string
org/apache/spark/ml/recommendation/ALS$
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/ml/recommendation
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
374986082715
state ThreadState
STATE_RUNNABLE

NativeMethodSample

profiling default startTime every chunk 11 17 21 25 26 27 graal vm

Category: Java Virtual Machine / Profiling

Snapshot of a threads state when in 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/sampling/jfrThreadSampler.cpp:

    case _thread_in_native_trans:
      break;
    case _thread_in_native:
      return true;
    default:
      ShouldNotReachHere();
      break;
  }
  return false;
}

class JfrThreadSampleClosure {
 public:
  JfrThreadSampleClosure(EventExecutionSample* events, EventNativeMethodSample* events_native);
  ~JfrThreadSampleClosure() {}
  EventExecutionSample* next_event() { return &_events[_added_java++]; }
  EventNativeMethodSample* next_event_native() { return &_events_native[_added_native++]; }
  void commit_events(JfrSampleType type);
  bool do_sample_thread(JavaThread* thread, JfrStackFrame* frames, u4 max_frames, JfrSampleType type);
  uint java_entries() { return _added_java; }
  uint native_entries() { return _added_native; }

 private:
  bool sample_thread_in_java(JavaThread* thread, JfrStackFrame* frames, u4 max_frames);
  bool sample_thread_in_native(JavaThread* thread, JfrStackFrame* frames, u4 max_frames);
  EventExecutionSample* _events;
  EventNativeMethodSample* _events_native;
  Thread* _self;
  uint _added_java;
  uint _added_native;
};

class OSThreadSampler : public SuspendedThreadTask {
 public:
  OSThreadSampler(JavaThread* thread,
                  JfrThreadSampleClosure& closure,
                  JfrStackFrame *frames,
                  u4 max_frames) : SuspendedThreadTask((Thread*)thread),

src/hotspot/share/jfr/periodic/sampling/jfrThreadSampler.cpp:

  virtual void call();
  bool success() { return _success; }
  JfrStackTrace& stacktrace() { return _stacktrace; }

 private:
  JfrThreadSampleClosure& _closure;
  JavaThread* _jt;
  oop _thread_oop;
  JfrStackTrace _stacktrace;
  bool _success;
};

static void write_native_event(JfrThreadSampleClosure& closure, JavaThread* jt, oop thread_oop) {
  EventNativeMethodSample *ev = closure.next_event_native();
  ev->set_starttime(JfrTicks::now());
  ev->set_sampledThread(JfrThreadLocal::thread_id(jt));
  ev->set_state(static_cast<u8>(java_lang_Thread::get_thread_status(thread_oop)));
}

void JfrNativeSamplerCallback::call() {
  // When a thread is only attach it will be native without a last java frame
  if (!_jt->has_last_Java_frame()) {
    return;
  }

src/hotspot/share/jfr/periodic/sampling/jfrThreadSampler.cpp:

  JfrNativeSamplerCallback cb(*this, thread, frames, max_frames);
  if (JfrOptionSet::sample_protection()) {
    ThreadCrashProtection crash_protection;
    if (!crash_protection.call(cb)) {
      log_error(jfr)("Thread method sampler crashed for native");
    }
  } else {
    cb.call();
  }
  if (!cb.success()) {
    return false;
  }
  EventNativeMethodSample *event = &_events_native[_added_native - 1];
  traceid id = JfrStackTraceRepository::add(cb.stacktrace());
  assert(id != 0, "Stacktrace id should not be 0");
  event->set_stackTrace(id);
  return true;
}

static const uint MAX_NR_OF_JAVA_SAMPLES = 5;
static const uint MAX_NR_OF_NATIVE_SAMPLES = 1;

void JfrThreadSampleClosure::commit_events(JfrSampleType type) {
  if (JAVA_SAMPLE == type) {
    assert(_added_java > 0 && _added_java <= MAX_NR_OF_JAVA_SAMPLES, "invariant");
    if (EventExecutionSample::is_enabled()) {
      for (uint i = 0; i < _added_java; ++i) {
        _events[i].commit();
      }
    }
  } else {
    assert(NATIVE_SAMPLE == type, "invariant");
    assert(_added_native > 0 && _added_native <= MAX_NR_OF_NATIVE_SAMPLES, "invariant");
    if (EventNativeMethodSample::is_enabled()) {
      for (uint i = 0; i < _added_native; ++i) {
        _events_native[i].commit();
      }
    }
  }
}

JfrThreadSampleClosure::JfrThreadSampleClosure(EventExecutionSample* events, EventNativeMethodSample* events_native) :
  _events(events),
  _events_native(events_native),
  _self(Thread::current()),
  _added_java(0),
  _added_native(0) {
}

class JfrThreadSampler : public NonJavaThread {
  friend class JfrThreadSampling;
 private:
  Semaphore _sample;

src/hotspot/share/jfr/periodic/sampling/jfrThreadSampler.cpp:

const JfrBuffer* JfrThreadSampler::get_enqueue_buffer() {
  const JfrBuffer* buffer = JfrTraceIdLoadBarrier::get_sampler_enqueue_buffer(this);
  return buffer != nullptr ? renew_if_full(buffer) : JfrTraceIdLoadBarrier::renew_sampler_enqueue_buffer(this);
}

const JfrBuffer* JfrThreadSampler::renew_if_full(const JfrBuffer* enqueue_buffer) {
  assert(enqueue_buffer != nullptr, "invariant");
  return enqueue_buffer->free_size() < _min_size ? JfrTraceIdLoadBarrier::renew_sampler_enqueue_buffer(this) : enqueue_buffer;
}

void JfrThreadSampler::task_stacktrace(JfrSampleType type, JavaThread** last_thread) {
  ResourceMark rm;
  EventExecutionSample samples[MAX_NR_OF_JAVA_SAMPLES];
  EventNativeMethodSample samples_native[MAX_NR_OF_NATIVE_SAMPLES];
  JfrThreadSampleClosure sample_task(samples, samples_native);

  const uint sample_limit = JAVA_SAMPLE == type ? MAX_NR_OF_JAVA_SAMPLES : MAX_NR_OF_NATIVE_SAMPLES;
  uint num_samples = 0;
  JavaThread* start = NULL;
  {
    elapsedTimer sample_time;
    sample_time.start();
    {
      MutexLocker tlock(Threads_lock);
      ThreadsListHandle tlh;

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

JVM_ENTRY_NO_ENV(void, jfr_subscribe_log_level(JNIEnv* env, jobject 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, jobject jvm, jstring path))
  JfrRepository::set_chunk_path(path, thread);
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_set_method_sampling_period(JNIEnv* env, jobject 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) {
    JfrThreadSampling::set_java_sample_period(periodMillis);
  } else {
    JfrThreadSampling::set_native_sample_period(periodMillis);
  }
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_store_metadata_descriptor(JNIEnv* env, jobject jvm, jbyteArray descriptor))
  JfrMetadataEvent::update(descriptor);
JVM_END

Configuration enabled period
profiling true 20 ms
default true 20 ms

Field Type Description
sampledThread Thread Thread
stackTrace StackTrace Stack Trace
state ThreadState Thread State

Examples 3
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
shuffle-boss-6-1
javaThreadId long
1153
osName string
shuffle-boss-6-1
osThreadId long
3739
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(IJII)I
hidden boolean
false
modifiers int
264
name string
wait
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
sun/nio/ch/EPoll
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
21.0.9
name string
sun/nio/ch
type FrameType
Native
truncated boolean
false
startTime long: millis
380111937849
state ThreadState
STATE_RUNNABLE
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
SparkUI-1150
javaThreadId long
1150
osName string
SparkUI-1150
osThreadId long
4380
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(IJII)I
hidden boolean
false
modifiers int
264
name string
wait
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
sun/nio/ch/EPoll
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
21.0.9
name string
sun/nio/ch
type FrameType
Native
truncated boolean
false
startTime long: millis
367155848775
state ThreadState
STATE_RUNNABLE
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
SparkUI-1153
javaThreadId long
1153
osName string
SparkUI-1153
osThreadId long
3707
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(IJII)I
hidden boolean
false
modifiers int
264
name string
wait
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
sun/nio/ch/EPoll
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
21.0.9
name string
sun/nio/ch
type FrameType
Native
truncated boolean
false
startTime long: millis
278779400379
state ThreadState
STATE_RUNNABLE

JVM: Runtime

ContinuationFreeze

experimental startTime duration eventThread stackTrace 19 21 25 26 27

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:

  JVMTI_ONLY(jvmti_yield_cleanup(thread, cont)); // can safepoint
  return freeze_epilog(thread, cont);
}

template<typename ConfigT>
static inline int freeze_internal(JavaThread* current, intptr_t* const sp) {
  assert(!current->has_pending_exception(), "");

#ifdef ASSERT
  log_trace(continuations)("~~~~ freeze sp: " INTPTR_FORMAT, p2i(current->last_continuation()->entry_sp()));
  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));

Configuration enabled stackTrace threshold
profiling false false 0 ms
default false false 0 ms

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 26 27

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);

Configuration enabled stackTrace threshold
profiling false false 0 ms
default false false 0 ms

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 26 27

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

Configuration enabled
profiling false
default false

Field Type Description
id ulong Continuation ID
size uint Size
allocate boolean Allocated New

ContinuationFreezeSlow

experimental startTime eventThread 20 21 25 26 27

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();

Configuration enabled
profiling false
default false

Field Type Description
id ulong Continuation ID

ContinuationThawFast

experimental startTime eventThread 20 21 25 26 27

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
  set_anchor(_thread, rs.sp());
  log_frames(_thread);

Configuration enabled
profiling false
default false

Field Type Description
id ulong Continuation ID
full boolean Full
size uint Size

ContinuationThawSlow

experimental startTime eventThread 20 21 25 26 27

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:

inline bool ThawBase::seen_by_gc() {
  return _barriers || _cont.tail()->is_gc_mode();
}

NOINLINE intptr_t* ThawBase::thaw_slow(stackChunkOop chunk, bool return_barrier) {
  LogTarget(Trace, continuations) lt;
  if (lt.develop_is_enabled()) {
    LogStream ls(lt);
    ls.print_cr("thaw slow return_barrier: %d " INTPTR_FORMAT, return_barrier, 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 = (return_barrier ? 1 : 2);

  _stream = StackChunkFrameStream<ChunkFrames::Mixed>(chunk);

Configuration enabled
profiling false
default false

Field Type Description
id ulong Continuation ID

ReservedStackActivation

profiling default startTime eventThread stackTrace 11 17 21 25 26 27

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 != NULL; sd = sd->sender()) {
          method = sd->method();
          if (method != NULL && 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,

Configuration enabled stackTrace
profiling true true
default true true

Field Type Description
method Method Java Method

SafepointBegin

profiling default startTime duration eventThread 11 17 21 25 26 27 graal vm

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());

  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().
  Threads_lock->lock();

  assert( _state == _not_synchronized, "trying to safepoint synchronize with wrong state");

  int nof_threads = Threads::number_of_threads();

Configuration enabled threshold
profiling true 0 ms
default true 10 ms

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
jniCriticalThreadCount int
0
safepointId ulong
1511
startTime long: millis
285681986551
totalThreadCount int
185
jniCriticalThreadCount int
0
safepointId ulong
755
startTime long: millis
443225661577
totalThreadCount int
89
jniCriticalThreadCount int
0
safepointId ulong
1253
startTime long: millis
440563305461
totalThreadCount int
44

SafepointStateSynchronization

startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime / Safepoint

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:

    event.set_totalThreadCount(thread_count);
    event.set_jniCriticalThreadCount(critical_thread_count);
    event.commit();
  }
}

static void post_safepoint_cleanup_event(EventSafepointCleanup& event, uint64_t safepoint_id) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.commit();
  }
}

static void post_safepoint_synchronize_event(EventSafepointStateSynchronization& event,
                                             uint64_t safepoint_id,
                                             int initial_number_of_threads,
                                             int threads_waiting_to_block,
                                             uint64_t 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(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 * (NANOUNITS / MILLIUNITS);
    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.
  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
  // Mark all threads

Configuration enabled threshold
profiling false 0 ms
default false 10 ms

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
initialThreadCount int
2
iterations int
3
runningThreadCount int
0
safepointId ulong
1215
startTime long: millis
413436424922
initialThreadCount int
2
iterations int
3
runningThreadCount int
0
safepointId ulong
1546
startTime long: millis
295877413475
initialThreadCount int
3
iterations int
3
runningThreadCount int
0
safepointId ulong
715
startTime long: millis
409615943916

SafepointCleanup

startTime duration eventThread 11 17 21 until JDK 23

Category: Java Virtual Machine / Runtime / Safepoint

Safepointing begin running cleanup tasks

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_cleanup_event(EventSafepointCleanup& event, uint64_t safepoint_id) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.commit();
  }
}

static void post_safepoint_synchronize_event(EventSafepointStateSynchronization& event,
                                             uint64_t safepoint_id,
                                             int initial_number_of_threads,
                                             int threads_waiting_to_block,
                                             uint64_t iterations) {

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

  // Update the count of active JNI critical regions
  GCLocker::set_jni_lock_count(_current_jni_active_count);

  post_safepoint_synchronize_event(sync_event,
                                   _safepoint_id,
                                   initial_running,
                                   _waiting_to_block, iterations);

  SafepointTracing::synchronized(nof_threads, initial_running, _nof_threads_hit_polling_page);

  // We do the safepoint cleanup first since a GC related safepoint
  // needs cleanup to be completed before running the GC op.
  EventSafepointCleanup cleanup_event;
  do_cleanup_tasks();
  post_safepoint_cleanup_event(cleanup_event, _safepoint_id);

  post_safepoint_begin_event(begin_event, _safepoint_id, nof_threads, _current_jni_active_count);
  SafepointTracing::cleanup();
}

void SafepointSynchronize::disarm_safepoint() {
  uint64_t active_safepoint_counter = _safepoint_counter;
  {
    JavaThreadIteratorWithHandle jtiwh;

Configuration enabled threshold
profiling false 0 ms
default false 10 ms

Field Type Description
safepointId ulong Safepoint Identifier

Examples 3
safepointId ulong
1563
startTime long: millis
303912329218
safepointId ulong
716
startTime long: millis
409632610398
safepointId ulong
1243
startTime long: millis
439692620336

SafepointCleanupTask

startTime duration eventThread 11 17 21 until JDK 23

Category: Java Virtual Machine / Runtime / Safepoint

Safepointing begin running cleanup tasks

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,
                                             uint64_t 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(iterations);
    event.commit();
  }
}

static void post_safepoint_cleanup_task_event(EventSafepointCleanupTask& event,
                                              uint64_t safepoint_id,
                                              const char* name) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.set_name(name);
    event.commit();
  }
}

static void post_safepoint_end_event(EventSafepointEnd& event, uint64_t safepoint_id) {
  if (event.should_commit()) {

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

  if (StringTable::needs_rehashing()) return true;
  if (SymbolTable::needs_rehashing()) return true;
  return false;
}

class ParallelCleanupTask : public WorkerTask {
private:
  SubTasksDone _subtasks;
  bool _do_lazy_roots;

  class Tracer {
  private:
    const char*               _name;
    EventSafepointCleanupTask _event;
    TraceTime                 _timer;

  public:
    Tracer(const char* name) :
        _name(name),
        _event(),
        _timer(name, TRACETIME_LOG(Info, safepoint, cleanup)) {}
    ~Tracer() {
      post_safepoint_cleanup_task_event(_event, SafepointSynchronize::safepoint_id(), _name);
    }
  };

Configuration enabled threshold
profiling false 0 ms
default false 10 ms

Field Type Description
safepointId ulong Safepoint Identifier
name string Task Name The task name

Examples 3
name string
updating inline caches
safepointId ulong
1505
startTime long: millis
282994636553
name string
updating inline caches
safepointId ulong
710
startTime long: millis
400780411521
name string
updating inline caches
safepointId ulong
1254
startTime long: millis
440687058892

SafepointEnd

startTime duration eventThread 11 17 21 25 26 27 graal vm

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:

static void post_safepoint_cleanup_task_event(EventSafepointCleanupTask& event,
                                              uint64_t safepoint_id,
                                              const char* name) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.set_name(name);
    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:

  } // ~JavaThreadIteratorWithHandle

  // 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");
  EventSafepointEnd event;
  assert(Thread::current()->is_VM_thread(), "Only VM thread can execute a safepoint");

  disarm_safepoint();

  Universe::heap()->safepoint_synchronize_end();

  SafepointTracing::end();

  post_safepoint_end_event(event, safepoint_id());
}

Configuration enabled threshold
profiling false 0 ms
default false 10 ms

Field Type Description
safepointId ulong Safepoint Identifier

Examples 3
safepointId ulong
1235
startTime long: millis
432434584524
safepointId ulong
725
startTime long: millis
426572327996
safepointId ulong
1512
startTime long: millis
285820577028

ExecuteVMOperation

profiling default startTime duration eventThread 11 17 21 25 26 27 graal vm

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 != NULL, "invariant");
  assert(op != NULL, "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;
    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);
  }

}

Configuration enabled threshold
profiling true 0 ms
default true 10 ms

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
blocking boolean
true
caller Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
1
osName string
main
osThreadId long
2255
virtual boolean
false
operation VMOperationType
ICBufferFull
safepoint boolean
true
safepointId ulong
1232
startTime long: millis
431711628841
blocking boolean
true
caller Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
1
osName string
main
osThreadId long
2926
virtual boolean
false
operation VMOperationType
ParallelGCFailedAllocation
safepoint boolean
true
safepointId ulong
741
startTime long: millis
434837481051
blocking boolean
true
caller Thread
group ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
JFR Recorder Thread
javaThreadId long
18
osName string
JFR Recorder Thread
osThreadId long
2307
virtual boolean
false
operation VMOperationType
JFRSafepointWrite
safepoint boolean
true
safepointId ulong
1492
startTime long: millis
279789345284

Shutdown

profiling default startTime eventThread stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime

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/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/prims/jvm.cpp:

// java.lang.Runtime /////////////////////////////////////////////////////////////////////////

extern volatile jint vm_created;

JVM_ENTRY_NO_ENV(void, JVM_BeforeHalt())
#if INCLUDE_CDS
  // Link all classes for dynamic CDS dumping before vm exit.
  if (DynamicArchive::should_dump_at_vm_exit()) {
    DynamicArchive::prepare_for_dump_at_exit();
  }
#endif
  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/jfr/recorder/repository/jfrEmergencyDump.cpp:

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

static void post_events(bool exception_handler, Thread* thread) {
  if (exception_handler) {
    EventShutdown e;
    e.set_reason("VM Error");
    e.commit();
  } else {
    // OOM
    LeakProfiler::emit_events(max_jlong, false, false);
  }
  EventDumpReason event;
  event.set_reason(exception_handler ? "Crash" : "Out of Memory");
  event.set_recordingId(-1);
  event.commit();
}

Configuration enabled stackTrace
profiling true true
default true true

Field Type Description
reason string Reason Reason for JVM shutdown

Examples 3
reason string
No remaining non-daemon Java threads
stackTrace StackTrace
null
startTime long: millis
367335947087
reason string
No remaining non-daemon Java threads
stackTrace StackTrace
null
startTime long: millis
482443717902
reason string
No remaining non-daemon Java threads
stackTrace StackTrace
null
startTime long: millis
493401214751

SymbolTableStatistics

profiling default startTime duration every chunk 13 17 21 25 26 27

Category: Java Virtual Machine / Runtime / Tables

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());

Configuration enabled period
profiling true 10 s
default true 10 s

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
bucketCount ulong
131072
bucketCountAverage float
4.257683
bucketCountMaximum ulong
17
bucketCountStandardDeviation float
2.0666494
bucketCountVariance float
4.27104
entryCount ulong
558063
insertionRate float
4175.612
removalRate float
56.05631
startTime long: millis
461135988081
totalFootprint ulong: bytes
63244656
bucketCount ulong
65536
bucketCountAverage float
7.622528
bucketCountMaximum ulong
20
bucketCountStandardDeviation float
2.7644002
bucketCountVariance float
7.641908
entryCount ulong
499550
insertionRate float
22.696087
removalRate float
0.32451954
startTime long: millis
381017363759
totalFootprint ulong: bytes
54106528
bucketCount ulong
131072
bucketCountAverage float
4.242546
bucketCountMaximum ulong
17
bucketCountStandardDeviation float
2.062593
bucketCountVariance float
4.254289
entryCount ulong
556079
insertionRate float
4675.343
removalRate float
212.15857
startTime long: millis
332335425574
totalFootprint ulong: bytes
63054904

StringTableStatistics

profiling default startTime duration every chunk 13 17 21 25 26 27

Category: Java Virtual Machine / Runtime / Tables

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());

Configuration enabled period
profiling true 10 s
default true 10 s

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
bucketCount ulong
65536
bucketCountAverage float
1.8048859
bucketCountMaximum ulong
10
bucketCountStandardDeviation float
1.3388131
bucketCountVariance float
1.7924206
entryCount ulong
118285
insertionRate float
419.1846
removalRate float
12.165391
startTime long: millis
483701102080
totalFootprint ulong: bytes
12129992
bucketCount ulong
65536
bucketCountAverage float
1.5897064
bucketCountMaximum ulong
10
bucketCountStandardDeviation float
1.2600222
bucketCountVariance float
1.5876559
entryCount ulong
104183
insertionRate float
282.06146
removalRate float
45.843613
startTime long: millis
342490724557
totalFootprint ulong: bytes
11732096
bucketCount ulong
65536
bucketCountAverage float
1.4304657
bucketCountMaximum ulong
9
bucketCountStandardDeviation float
1.1916248
bucketCountVariance float
1.4199697
entryCount ulong
93747
insertionRate float
10.4909935
removalRate float
2.3701193
startTime long: millis
435465742490
totalFootprint ulong: bytes
10463904

ThreadDump

profiling default startTime duration every chunk 11 17 21 25 26 27

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/jfr/periodic/jfrThreadDumpEvent.cpp:

  JavaThread* THREAD = JavaThread::current(); // For exception macros.
  assert(!HAS_PENDING_EXCEPTION, "dcmd does not expect pending exceptions on entry!");
  // delegate to DCmd execution
  DCmd::parse_and_execute(DCmd_Source_Internal, &st, cmd, ' ', THREAD);
  if (HAS_PENDING_EXCEPTION) {
    log_debug(jfr, system)("unable to create jfr event for DCMD %s", cmd);
    log_debug(jfr, system)("exception type: %s", PENDING_EXCEPTION->klass()->external_name());
    // don't unwind this exception
    CLEAR_PENDING_EXCEPTION;
    // if exception occurred,
    // reset stream.
    st.reset();
    return false;
  }
  return true;
}

// caller needs ResourceMark
const char* JfrDcmdEvent::thread_dump() {
  assert(EventThreadDump::is_enabled(), "invariant");
  bufferedStream st;
  execute_dcmd(st, "Thread.print");
  return st.as_string();
}

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 jfrSamples.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);

Configuration enabled period
profiling true 60 s
default true everyChunk

Field Type Description
result string Thread Dump

Examples 3
result string
2026-01-04 00:46:43 Full thread dump OpenJDK 64-Bit Server VM (21.0.9+10-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x00007f303c3b0e00, length=45, elements={ 0x00007f30d4057c80, 0x00007f30d41320c0, 0x00007f30d41335f0, 0x00007f30d4134d40, 0x00007f30d4136340, 0x00007f30d41378
startTime long: millis
435465753170
result string
2026-01-04 00:44:59 Full thread dump OpenJDK 64-Bit Server VM (21.0.9+10-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x00007f58c0689570, length=68, elements={ 0x00007f594c057cc0, 0x00007f594c196b80, 0x00007f594c1980e0, 0x00007f594c199860, 0x00007f594c19ae90, 0x00007f594c19c4
startTime long: millis
332347553041
result string
2026-01-04 00:47:08 Full thread dump OpenJDK 64-Bit Server VM (21.0.9+10-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x00007fb93401c0d0, length=51, elements={ 0x00007fb9b4057c60, 0x00007fb9b40ac860, 0x00007fb9b40add90, 0x00007fb9b40af4e0, 0x00007fb9b40b0ae0, 0x00007fb9b40b20
startTime long: millis
472193057213

NativeLibrary

profiling default startTime every chunk 11 17 21 25 26 27

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/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();

Configuration enabled period
profiling true everyChunk
default true everyChunk

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

Examples 3
baseAddress ulong: address
139847843053568
name string
/lib/x86_64-linux-gnu/libdl.so.2
startTime long: millis
371363139548
topAddress ulong: address
139847843074048
baseAddress ulong: address
140019387858944
name string
/tmp/libnetty_transport_native_epoll_x86_6410710955449224643303.so
startTime long: millis
278185459316
topAddress ulong: address
140019392053248
baseAddress ulong: address
140435720839168
name string
/opt/hostedtoolcache/Java_SapMachine_jdk/21.0.9/x64/lib/libmanagement.so
startTime long: millis
378913078991
topAddress ulong: address
140435720863744

ModuleRequire

profiling default startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime / Modules

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* const)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);

Configuration enabled period
profiling true endChunk
default true endChunk

Field Type Description
source Module Source Module
requiredModule Module Required Module

Examples 3
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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
jdk/internal/loader
location string
jrt:/jdk.compiler
name string
jdk.compiler
version string
21.0.9
source Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
21.0.9
name string
jdk/internal/loader
location string
jrt:/jdk.jshell
name string
jdk.jshell
version string
21.0.9
startTime long: millis
382361859327
requiredModule 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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
source 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
21.0.9
name string
java/net
location string
null
name string
jdk.proxy8
version string
null
startTime long: millis
374646122291
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$PlatformClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
jdk/internal/loader
location string
jrt:/java.compiler
name string
java.compiler
version string
21.0.9
source Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
21.0.9
name string
jdk/internal/loader
location string
jrt:/jdk.jdeps
name string
jdk.jdeps
version string
21.0.9
startTime long: millis
279631473390

ModuleExport

profiling default startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime / Modules

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* const)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 != NULL, "invariant");
  assert(_module != NULL, "invariant");

Configuration enabled period
profiling true endChunk
default true endChunk

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
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/logging/log4j/core/appender/mom
startTime long: millis
279631749684
targetModule Module
null
exportedPackage Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.xml
name string
java.xml
version string
21.0.9
name string
org/w3c/dom/ls
startTime long: millis
382362306931
targetModule Module
null
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/paths
startTime long: millis
374646561997
targetModule Module
null

Java Application

ThreadStart

profiling default startTime eventThread stackTrace 11 17 21 25 26 27 graal vm

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:

const JfrBlobHandle& JfrThreadLocal::thread_blob() const {
  return _thread;
}

static void send_java_thread_start_event(JavaThread* jt) {
  assert(jt != NULL, "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) {
  assign_thread_id(t, t->jfr_thread_local());
  if (JfrRecorder::is_recording()) {
    JfrCheckpointManager::write_checkpoint(t);

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 = NULL;
  }

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

#if INCLUDE_JNI_CHECK
  if (CheckJNICalls) return jni_functions_check();
#endif // INCLUDE_JNI_CHECK
  return &jni_NativeInterface;
}

// Returns the function structure
struct JNINativeInterface_* jni_functions_nocheck() {
  return &jni_NativeInterface;
}

static void post_thread_start_event(const JavaThread* jt) {
  assert(jt != NULL, "invariant");
  EventThreadStart event;
  if (event.should_commit()) {
    event.set_thread(JFR_JVM_THREAD_ID(jt));
    event.set_parentThread((traceid)0);
#if INCLUDE_JFR
    if (EventThreadStart::is_stacktrace_enabled()) {
      jt->jfr_thread_local()->set_cached_stack_trace_id((traceid)0);
      event.commit();
      jt->jfr_thread_local()->clear_cached_stack_trace();
    } else
#endif
    {
      event.commit();
    }
  }
}

Configuration enabled stackTrace
profiling true true
default true true

Field Type Description
thread Thread New Java Thread
parentThread Thread Parent Java Thread

Examples 3
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
dispatcher-BlockManagerEndpoint1
javaThreadId long
1150
osName string
dispatcher-BlockManagerEndpoint1
osThreadId long
3704
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
2
lineNumber int
2577
method Method
descriptor string
(Ljava/lang/Thread;Ljdk/internal/vm/ThreadContainer;)V
hidden boolean
false
modifiers int
1
name string
start
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/System$2
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
21.0.9
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
291247493123
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-storage-async-thread-pool-63
javaThreadId long
1299
osName string
block-manager-storage-async-thread-pool-63
osThreadId long
3901
virtual boolean
false
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-storage-async-thread-pool-86
javaThreadId long
1333
osName string
block-manager-storage-async-thread-pool-86
osThreadId long
4594
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
2
lineNumber int
2577
method Method
descriptor string
(Ljava/lang/Thread;Ljdk/internal/vm/ThreadContainer;)V
hidden boolean
false
modifiers int
1
name string
start
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/System$2
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
21.0.9
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
420314961376
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-ask-thread-pool-56
javaThreadId long
1334
osName string
block-manager-ask-thread-pool-56
osThreadId long
4595
virtual boolean
false
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-storage-async-thread-pool-71
javaThreadId long
1295
osName string
block-manager-storage-async-thread-pool-71
osThreadId long
3912
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
2
lineNumber int
2577
method Method
descriptor string
(Ljava/lang/Thread;Ljdk/internal/vm/ThreadContainer;)V
hidden boolean
false
modifiers int
1
name string
start
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/System$2
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
21.0.9
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
413788880469
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-storage-async-thread-pool-73
javaThreadId long
1297
osName string
block-manager-storage-async-thread-pool-73
osThreadId long
3914
virtual boolean
false

ThreadEnd

profiling default startTime eventThread 11 17 21 25 26 27 graal vm

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(t != NULL, "invariant");
  assert(Thread::current() == t, "invariant");
  assert(!tl->is_dead(), "invariant");
  assert(tl->shelved_buffer() == NULL, "invariant");
  tl->_dead = true;
  tl->release(t);
}

static void send_java_thread_end_event(JavaThread* jt, traceid tid) {
  assert(jt != NULL, "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 != NULL, "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_JVMCI
  if (EnableJVMCI) {
    JVMCI::shutdown(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.
  if (PeriodicTask::num_tasks() > 0) {
    WatcherThread::stop();

Configuration enabled
profiling true
default true

Field Type Description
thread Thread Java Thread

Examples 3
startTime long: millis
424991229702
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-storage-async-thread-pool-33
javaThreadId long
1231
osName string
block-manager-storage-async-thread-pool-33
osThreadId long
3840
virtual boolean
false
startTime long: millis
310957695435
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
map-output-dispatcher-4
javaThreadId long
1144
osName string
map-output-dispatcher-4
osThreadId long
3699
virtual boolean
false
startTime long: millis
386008685596
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
QueryStageCreator-2
javaThreadId long
1114
osName string
QueryStageCreator-2
osThreadId long
4341
virtual boolean
false

ThreadPark

profiling default startTime duration eventThread stackTrace 11 17 21 25 26 27 graal vm

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 Atomic::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 Atomic::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 != NULL, "invariant");
  event->set_parkedClass((obj != NULL) ? obj->klass() : NULL);
  event->set_timeout(timeout_nanos);
  event->set_until(until_epoch_millis);
  event->set_address((obj != NULL) ? (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 {

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

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
address ulong: address
31746020680
parkedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionObject
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
java/util/concurrent/locks
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
jdk/internal/misc
type FrameType
Native
truncated boolean
false
startTime long: millis
382158412824
timeout long: nanos
-9223372036854775808
until long: epochmillis
-9223372036854775808
address ulong: address
30321610296
parkedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer$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
21.0.9
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
21.0.9
name string
jdk/internal/misc
type FrameType
Native
truncated boolean
false
startTime long: millis
279463609442
timeout long: nanos
-9223372036854775808
until long: epochmillis
-9223372036854775808
address ulong: address
30343154712
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
21.0.9
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
21.0.9
name string
jdk/internal/misc
type FrameType
Native
truncated boolean
false
startTime long: millis
366304068487
timeout long: nanos
-9223372036854775808
until long: epochmillis
-9223372036854775808

JavaMonitorEnter

profiling default startTime duration eventThread stackTrace 11 17 21 25 26 27 graal vm

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:

    // above lost the race to async deflation. Undo the work and
    // force the caller to retry.
    const oop l_object = object();
    if (l_object != NULL) {
      // Attempt to restore the header/dmw to the object's header so that
      // we only retry once if the deflater thread happens to be slow.
      install_displaced_markword_in_object(l_object);
    }
    current->_Stalled = 0;
    add_to_contentions(-1);
    return false;
  }

  JFR_ONLY(JfrConditionalFlushWithStacktrace<EventJavaMonitorEnter> flush(current);)
  EventJavaMonitorEnter event;
  if (event.is_started()) {
    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.
    event.set_address((uintptr_t)this);
  }

  { // Change java thread status to indicate blocked on monitor enter.
    JavaThreadBlockedOnMonitorEnterState jtbmes(current, this);

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

  if (_recursions != 0) {
    _recursions--;        // this is simple recursive enter
    return;
  }

  // Invariant: after setting Responsible=null an thread must execute
  // a MEMBAR or other serializing instruction before fetching EntryList|cxq.
  _Responsible = NULL;

#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 (;;) {
    assert(current == owner_raw(), "invariant");

    // Drop the lock.
    // release semantics: prior loads and stores from within the critical section
    // must not float (reorder) past the following store that drops the lock.
    // Uses a storeload to separate release_store(owner) from the

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Field Type Description
monitorClass Class Monitor Class
previousOwner Thread Previous Monitor Owner
address ulong: address Monitor Address

Examples 3
address ulong: address
140432266840256
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
21.0.9
name string
java/lang
previousOwner Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Thread-295
javaThreadId long
1923
osName string
Thread-295
osThreadId long
4573
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
573
method Method
descriptor string
(Ljava/lang/String;Z)Ljava/lang/Class;
hidden boolean
false
modifiers int
4
name string
loadClass
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
21.0.9
name string
java/lang
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
483055869859
address ulong: address
139845144791808
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
21.0.9
name string
java/lang
previousOwner Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
shuffle-server-7-1
javaThreadId long
1366
osName string
shuffle-server-7-1
osThreadId long
4633
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
573
method Method
descriptor string
(Ljava/lang/String;Z)Ljava/lang/Class;
hidden boolean
false
modifiers int
4
name string
loadClass
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
21.0.9
name string
java/lang
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
435413996514
address ulong: address
140018462046608
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
21.0.9
name string
java/lang
previousOwner Thread
group ThreadGroup
name string
finagle/netty4
parent ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
finagle/netty4-2-4
javaThreadId long
1925
osName string
finagle/netty4-2-4
osThreadId long
4560
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
8
lineNumber int
162
method Method
descriptor string
(Lcom/twitter/finagle/http/Request;)Lcom/twitter/util/Future;
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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/renaissance/twitter/finagle/FinagleChirper$Master
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
org/renaissance/twitter/finagle
type FrameType
Interpreted
truncated boolean
true
startTime long: millis
356654673178

JavaMonitorWait

profiling default startTime duration eventThread stackTrace 11 17 21 25 26 27 graal vm

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:

    _recursions = 0;
    return true;
  }
  THROW_MSG_(vmSymbols::java_lang_IllegalMonitorStateException(),
             "current thread is not owner", false);
}

static inline bool is_excluded(const Klass* monitor_klass) {
  assert(monitor_klass != nullptr, "invariant");
  NOT_JFR_RETURN_(false);
  JFR_ONLY(return vmSymbols::jfr_chunk_rotation_monitor() == monitor_klass->name());
}

static void post_monitor_wait_event(EventJavaMonitorWait* event,
                                    ObjectMonitor* monitor,
                                    uint64_t notifier_tid,
                                    jlong timeout,
                                    bool timedout) {
  assert(event != NULL, "invariant");
  assert(monitor != NULL, "invariant");
  const Klass* monitor_klass = monitor->object()->klass();
  if (is_excluded(monitor_klass)) {
    return;
  }
  event->set_monitorClass(monitor_klass);

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 event;

  // check for a pending interrupt
  if (interruptible && current->is_interrupted(true) && !HAS_PENDING_EXCEPTION) {
    // 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
      // wait was not timed out due to thread interrupt.
      JvmtiExport::post_monitor_waited(current, this, false);

      // In this short circuit of the monitor wait protocol, the
      // current thread never drops ownership of the monitor and

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

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
address ulong: address
139845750849184
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
21.0.9
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-3
javaThreadId long
1443
osName string
Executor task launch worker-3
osThreadId long
4718
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
21.0.9
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
444359123564
timedOut boolean
false
timeout long: millis
0
address ulong: address
140432882605872
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/util/TaskQueue
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
21.0.9
name string
java/util
notifier Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
1
osName string
main
osThreadId long
2255
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
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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
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null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
458051398347
timedOut boolean
false
timeout long: millis
0
address ulong: address
140017681159504
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
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null
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jrt:/java.base
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java.base
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name string
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notifier Thread
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Executor task launch worker-0
javaThreadId long
1434
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Executor task launch worker-0
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4045
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stackTrace StackTrace
frames StackFrame
bytecodeIndex int
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lineNumber int
-1
method Method
descriptor string
(J)V
hidden boolean
false
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274
name string
wait0
type Class
classLoader ClassLoader
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bootstrap
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null
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modifiers int
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java/lang/Object
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module Module
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startTime long: millis
326105236048
timedOut boolean
false
timeout long: millis
0

JavaMonitorInflate

profiling startTime duration eventThread stackTrace 11 17 21 25 26 27 graal vm

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:

  if (!ret_code) {
    log_info(monitorinflation)("Async Deflation DID NOT happen after %d checks.", N_CHECKS);
  }

  return ret_code;
}

jlong ObjectSynchronizer::time_since_last_async_deflation_ms() {
  return (os::javaTimeNanos() - last_async_deflation_time_ns()) / (NANOUNITS / MILLIUNITS);
}

static void post_monitor_inflate_event(EventJavaMonitorInflate* event,
                                       const oop obj,
                                       ObjectSynchronizer::InflateCause cause) {
  assert(event != NULL, "invariant");
  event->set_monitorClass(obj->klass());
  event->set_address((uintptr_t)(void*)obj);
  event->set_cause((u1)cause);
  event->commit();
}

// Fast path code shared by multiple functions
void ObjectSynchronizer::inflate_helper(oop obj) {
  markWord mark = obj->mark_acquire();
  if (mark.has_monitor()) {
    ObjectMonitor* monitor = mark.monitor();
    markWord dmw = monitor->header();
    assert(dmw.is_neutral(), "sanity check: header=" INTPTR_FORMAT, dmw.value());
    return;
  }
  (void)inflate(Thread::current(), obj, inflate_cause_vm_internal);
}

ObjectMonitor* ObjectSynchronizer::inflate(Thread* current, oop object,
                                           const InflateCause cause) {
  EventJavaMonitorInflate event;

  for (;;) {
    const markWord mark = object->mark_acquire();

    // The mark can be in one of the following states:
    // *  Inflated     - just return
    // *  Stack-locked - coerce it to inflated
    // *  INFLATING    - busy wait for conversion to complete
    // *  Neutral      - aggressively inflate the object.

    // CASE: inflated

Configuration enabled stackTrace threshold
profiling true true 10 ms
default false true 20 ms

Field Type Description
monitorClass Class Monitor Class
address ulong: address Monitor Address
cause InflateCause Monitor Inflation Cause Cause of inflation

ObjectAllocationInNewTLAB

startTime eventThread stackTrace 11 17 21 25 26 27 graal vm

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()) {

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
objectClass Class Object Class Class of allocated object
allocationSize ulong: bytes Allocation Size
tlabSize ulong: bytes TLAB Size

Examples 3
allocationSize ulong: bytes
80
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
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false
modifiers int
1041
name string
[Ljava/lang/Object;
package Package
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true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
java/lang
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
3
lineNumber int
51
method Method
descriptor string
()V
hidden boolean
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1
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<init>
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classLoader ClassLoader
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bootstrap
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java/net/URLClassLoader
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module Module
classLoader ClassLoader
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bootstrap
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null
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jrt:/java.base
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java.base
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java/net
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scala/collection/mutable/ArrayBuffer
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true
module Module
classLoader ClassLoader
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classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
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1
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java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
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bootstrap
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null
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jrt:/java.base
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java.base
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java/net
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null
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null
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scala/collection/mutable
type FrameType
Inlined
truncated boolean
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startTime long: millis
279232665332
tlabSize ulong: bytes
819616
allocationSize ulong: bytes
80
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[Ljava/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
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21.0.9
name string
java/lang
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51
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descriptor string
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classLoader ClassLoader
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classLoader ClassLoader
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bootstrap
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null
hidden boolean
false
modifiers int
1
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java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
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bootstrap
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null
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jrt:/java.base
name string
java.base
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21.0.9
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java/net
hidden boolean
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scala/collection/mutable/ArrayBuffer
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true
module Module
classLoader ClassLoader
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classLoader ClassLoader
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bootstrap
type Class
null
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1
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java/net/URLClassLoader
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bootstrap
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null
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jrt:/java.base
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java.base
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21.0.9
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java/net
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null
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scala/collection/mutable
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Inlined
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374970666690
tlabSize ulong: bytes
1104760
allocationSize ulong: bytes
56
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
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1041
name string
[F
package Package
null
stackTrace StackTrace
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bytecodeIndex int
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method Method
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(Ljava/lang/Class;I)Ljava/lang/Object;
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9
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bootstrap
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null
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17
name string
java/lang/reflect/Array
package Package
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jrt:/java.base
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truncated boolean
true
startTime long: millis
371521584145
tlabSize ulong: bytes
4643424

ObjectAllocationOutsideTLAB

startTime eventThread stackTrace 11 17 21 25 26 27

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);

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
objectClass Class Object Class Class of allocated object
allocationSize ulong: bytes Allocation Size

Examples 3
allocationSize ulong: bytes
32784
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
52
lineNumber int
94
method Method
descriptor string
(Ljava/io/OutputStream;II)V
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false
modifiers int
2
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<init>
type Class
classLoader ClassLoader
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bootstrap
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java/io/BufferedOutputStream
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module Module
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bootstrap
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jrt:/java.base
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java.base
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JIT compiled
truncated boolean
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startTime long: millis
393315826061
allocationSize ulong: bytes
1040
objectClass Class
classLoader ClassLoader
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null
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bytecodeIndex int
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method Method
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modifiers int
0
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classLoader ClassLoader
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bootstrap
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java/io/ObjectInputStream$BlockDataInputStream
package Package
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module Module
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bootstrap
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jrt:/java.base
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null
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1041
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bytecodeIndex int
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method Method
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java/nio/HeapByteBuffer
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module Module
classLoader ClassLoader
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bootstrap
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Inlined
truncated boolean
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startTime long: millis
279072458599

ObjectAllocationSample

throttle profiling default startTime eventThread stackTrace 16 17 21 25 26 27

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/jfrObjectAllocationSample.cpp:

static THREAD_LOCAL int64_t _last_allocated_bytes = 0;

inline void send_allocation_sample(const Klass* klass, int64_t allocated_bytes) {
  assert(allocated_bytes > 0, "invariant");
  EventObjectAllocationSample event;
  if (event.should_commit()) {
    const int64_t weight = allocated_bytes - _last_allocated_bytes;
    assert(weight > 0, "invariant");
    event.set_objectClass(klass);
    event.set_weight(weight);
    event.commit();
    _last_allocated_bytes = allocated_bytes;
  }
}

inline bool send_allocation_sample_with_result(const Klass* klass, int64_t allocated_bytes) {
  assert(allocated_bytes > 0, "invariant");
  EventObjectAllocationSample event;
  if (event.should_commit()) {
    const int64_t weight = allocated_bytes - _last_allocated_bytes;
    assert(weight > 0, "invariant");
    event.set_objectClass(klass);
    event.set_weight(weight);
    event.commit();
    _last_allocated_bytes = allocated_bytes;
    return true;
  }
  return false;
}

Configuration enabled stackTrace throttle
profiling true true 300/s
default true true 150/s

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
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
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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
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name string
java/lang
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
23
lineNumber int
1083
method Method
descriptor string
(I)Ljava/lang/Integer;
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9
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type Class
classLoader ClassLoader
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bootstrap
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17
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java/lang/Integer
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exported boolean
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module Module
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bootstrap
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jrt:/java.base
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279499139907
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objectClass Class
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bootstrap
type Class
null
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modifiers int
24
name string
java/util/TreeMap$Entry
package Package
exported boolean
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module Module
classLoader ClassLoader
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bootstrap
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jrt:/java.base
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FileForce

profiling default startTime duration stackTrace 11 17 21 25 26 27

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

Category: Java Application

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/jdk.jfr/share/classes/jdk/jfr/events/EventConfigurations.java:

package jdk.jfr.events;
import jdk.jfr.internal.Utils;
import jdk.jfr.internal.event.EventConfiguration;

public final class EventConfigurations {
    public static final EventConfiguration SOCKET_READ = Utils.getConfiguration(SocketReadEvent.class);
    public static final EventConfiguration SOCKET_WRITE = Utils.getConfiguration(SocketWriteEvent.class);
    public static final EventConfiguration FILE_READ = Utils.getConfiguration(FileReadEvent.class);
    public static final EventConfiguration FILE_WRITE = Utils.getConfiguration(FileWriteEvent.class);
    public static final EventConfiguration FILE_FORCE = Utils.getConfiguration(FileForceEvent.class);
    public static final EventConfiguration ERROR_THROWN = Utils.getConfiguration(ErrorThrownEvent.class);
    public static final EventConfiguration EXCEPTION_THROWN = Utils.getConfiguration(ExceptionThrownEvent.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.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 AbstractJDKEvent {

    // 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/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileChannelImplInstrumentor.java:

    public void force(boolean metaData) throws IOException {
        EventConfiguration eventConfiguration = EventConfigurations.FILE_FORCE;
        if (!eventConfiguration.isEnabled()) {
            force(metaData);
            return;
        }
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            force(metaData);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileForceEvent.commit(start, duration, path, metaData);
            }
        }
    }

    @JIInstrumentationMethod
    public int read(ByteBuffer dst) throws IOException {
        EventConfiguration eventConfiguration = EventConfigurations.FILE_READ;
        if (!eventConfiguration.isEnabled()) {
            return read(dst);
        }
        int bytesRead = 0;

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

        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ExceptionThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ErrorThrownEvent.class,
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.class,

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Field Type Description
path string Path Full path of the file
metaData boolean Update Metadata Whether the file metadata is updated

VirtualThreadStart

experimental startTime duration stackTrace 19 21 25 26 27

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

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/events/VirtualThreadStartEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Experimental;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.MirrorEvent;

@Category("Java Application")
@Label("Virtual Thread Start")
@Name("jdk.VirtualThreadStart")
@MirrorEvent(className = "jdk.internal.event.VirtualThreadStartEvent")
@Experimental
public final class VirtualThreadStartEvent extends AbstractJDKEvent {

    @Label("Thread Id")
    public long javaThreadId;

}

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

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,

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 final static 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/java.base/share/classes/java/lang/VirtualThread.java:

     * mounted on the current (carrier) thread before the task runs. It unmounts
     * from its carrier thread when the task completes.
     */
    @ChangesCurrentThread
    private void run(Runnable task) {
        assert state == RUNNING;
        boolean notifyJvmti = notifyJvmtiEvents;

        // first mount
        mount();
        if (notifyJvmti) notifyJvmtiMountEnd(true);

        // emit JFR event if enabled
        if (VirtualThreadStartEvent.isTurnedOn()) {
            var event = new VirtualThreadStartEvent();
            event.javaThreadId = threadId();
            event.commit();
        }

        Object bindings = scopedValueBindings();
        try {
            runWith(bindings, task);
        } catch (Throwable exc) {
            dispatchUncaughtException(exc);
        } finally {
            try {

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
javaThreadId long Thread Id

SocketRead

profiling default startTime duration stackTrace 11 17 21 25 26 27

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

Category: Java Application

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/jdk.jfr/share/classes/jdk/jfr/events/EventConfigurations.java:

package jdk.jfr.events;
import jdk.jfr.internal.Utils;
import jdk.jfr.internal.event.EventConfiguration;

public final class EventConfigurations {
    public static final EventConfiguration SOCKET_READ = Utils.getConfiguration(SocketReadEvent.class);
    public static final EventConfiguration SOCKET_WRITE = Utils.getConfiguration(SocketWriteEvent.class);
    public static final EventConfiguration FILE_READ = Utils.getConfiguration(FileReadEvent.class);
    public static final EventConfiguration FILE_WRITE = Utils.getConfiguration(FileWriteEvent.class);
    public static final EventConfiguration FILE_FORCE = Utils.getConfiguration(FileForceEvent.class);
    public static final EventConfiguration ERROR_THROWN = Utils.getConfiguration(ErrorThrownEvent.class);
    public static final EventConfiguration EXCEPTION_THROWN = Utils.getConfiguration(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")
public final class SocketReadEvent extends AbstractJDKEvent {

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

    @Label("Remote Host")
    public String host;

    @Label("Remote Address")
    public String address;

    @Label("Remote Port")

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/SocketChannelImplInstrumentor.java:

                    int delimiterIndex = hostString.lastIndexOf('/');

                    String host = hostString.substring(0, delimiterIndex);
                    String address = hostString.substring(delimiterIndex + 1);
                    int port = isa.getPort();
                    if (bytesRead < 0) {
                        SocketReadEvent.commit(start, duration, host, address, port, 0, 0L, true);
                    } else {
                        SocketReadEvent.commit(start, duration, host, address, port, 0, bytesRead, false);
                    }
                } else {
                    UnixDomainSocketAddress udsa = (UnixDomainSocketAddress) remoteAddress;
                    String path = "[" + udsa.getPath().toString() + "]";
                    if (bytesRead < 0) {
                        SocketReadEvent.commit(start, duration, "Unix domain socket", path, 0, 0, 0L, true);
                    } else {
                        SocketReadEvent.commit(start, duration, "Unix domain socket", path, 0, 0, bytesRead, false);
                    }
                }
            }
        }
        return bytesRead;

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/SocketChannelImplInstrumentor.java:

                    int delimiterIndex = hostString.lastIndexOf('/');

                    String host = hostString.substring(0, delimiterIndex);
                    String address = hostString.substring(delimiterIndex + 1);
                    int port = isa.getPort();
                    if (bytesRead < 0) {
                        SocketReadEvent.commit(start, duration, host, address, port, 0, 0L, true);
                    } else {
                        SocketReadEvent.commit(start, duration, host, address, port, 0, bytesRead, false);
                    }
                } else {
                    UnixDomainSocketAddress udsa = (UnixDomainSocketAddress) remoteAddress;
                    String path = "[" + udsa.getPath().toString() + "]";
                    if (bytesRead < 0) {
                        SocketReadEvent.commit(start, duration, "Unix domain socket", path, 0, 0, 0L, true);
                    } else {
                        SocketReadEvent.commit(start, duration, "Unix domain socket", path, 0, 0, bytesRead, false);
                    }
                }
            }
        }
        return bytesRead;

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/SocketInputStreamInstrumentor.java:

        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            bytesRead = read(b, off, length);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                InetAddress remote = parent.getInetAddress();
                String host = remote.getHostName();
                String address = remote.getHostAddress();
                int port = parent.getPort();
                int timeout = parent.getSoTimeout();
                if (bytesRead < 0) {
                    SocketReadEvent.commit(start, duration, host, address, port, timeout, 0L, true);
                } else {
                    SocketReadEvent.commit(start, duration, host, address, port, timeout, bytesRead, false);
                }
            }
        }
        return bytesRead;
    }

    // private field in java.net.Socket$SocketInputStream
    private Socket parent;
}

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

        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ExceptionThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ErrorThrownEvent.class,
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.SecurityProviderServiceEvent.class,
        jdk.internal.event.ThreadSleepEvent.class,

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

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

ThreadSleep

profiling default startTime duration stackTrace 11 17 21 25 26 27

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

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/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")
@MirrorEvent(className = "jdk.internal.event.ThreadSleepEvent")
public final class ThreadSleepEvent extends AbstractJDKEvent {
    @Label("Sleep Time")
    @Timespan(Timespan.NANOSECONDS)
    public long time;
}

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

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,

src/java.base/share/classes/jdk/internal/event/ThreadSleepEvent.java:

package jdk.internal.event;

/**
 * Event recording thread sleeping.
 */

public final class ThreadSleepEvent extends Event {
    private static final ThreadSleepEvent EVENT = new ThreadSleepEvent();

    /**
     * Returns {@code true} if event is enabled, {@code false} otherwise.
     */
    public static boolean isTurnedOn() {
        return EVENT.isEnabled();
    }

    public long time;
}

src/java.base/share/classes/java/lang/VirtualThread.java:

    /**
     * Sleep the current virtual thread for the given sleep time.
     *
     * @param nanos the maximum number of nanoseconds to sleep
     * @throws InterruptedException if interrupted while sleeping
     */
    void sleepNanos(long nanos) throws InterruptedException {
        assert Thread.currentThread() == this;
        if (nanos >= 0) {
            if (ThreadSleepEvent.isTurnedOn()) {
                ThreadSleepEvent event = new ThreadSleepEvent();
                try {
                    event.time = nanos;
                    event.begin();
                    doSleepNanos(nanos);
                } finally {
                    event.commit();
                }
            } else {
                doSleepNanos(nanos);
            }
        }

src/java.base/share/classes/java/lang/Thread.java:

     *          cleared when this exception is thrown.
     */
    public static void sleep(long millis) throws InterruptedException {
        if (millis < 0) {
            throw new IllegalArgumentException("timeout value is negative");
        }

        if (currentThread() instanceof VirtualThread vthread) {
            long nanos = MILLISECONDS.toNanos(millis);
            vthread.sleepNanos(nanos);
            return;
        }

        if (ThreadSleepEvent.isTurnedOn()) {
            ThreadSleepEvent event = new ThreadSleepEvent();
            try {
                event.time = MILLISECONDS.toNanos(millis);
                event.begin();
                sleep0(millis);
            } finally {
                event.commit();
            }
        } else {
            sleep0(millis);
        }
    }

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Field Type Description
time long: nanos Sleep Time

Examples 3
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
5
lineNumber int
474
method Method
descriptor string
(Ljdk/internal/event/ThreadSleepEvent;)V
hidden boolean
false
modifiers int
10
name string
afterSleep
type 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
21.0.9
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
375003792949
time long: nanos
10000000
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
5
lineNumber int
474
method Method
descriptor string
(Ljdk/internal/event/ThreadSleepEvent;)V
hidden boolean
false
modifiers int
10
name string
afterSleep
type 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
21.0.9
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
279287204517
time long: nanos
10000000
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
5
lineNumber int
474
method Method
descriptor string
(Ljdk/internal/event/ThreadSleepEvent;)V
hidden boolean
false
modifiers int
10
name string
afterSleep
type 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
21.0.9
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
366315059863
time long: nanos
10000000

JavaErrorThrow

profiling default startTime duration stackTrace 11 17 21 25 26 27

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

Category: Java Application

An object derived from java.lang.Error has been created. OutOfMemoryErrors are ignored

Configuration enabled stackTrace
profiling true true
default true true

Field Type Description
message string Message
thrownClass Class Class

Examples 3
message string
static Lorg/apache/spark/rdd/RDD$$anon$1;.<clinit>()V
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
68
method Method
descriptor string
(Ljava/lang/String;)V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Error
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
21.0.9
name string
java/lang
type FrameType
Inlined
truncated boolean
true
startTime long: millis
449142332696
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
21.0.9
name string
java/lang
message string
static Lorg/apache/spark/executor/InputMetrics;.<clinit>()V
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
68
method Method
descriptor string
(Ljava/lang/String;)V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Error
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
21.0.9
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
442895336052
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
21.0.9
name string
java/lang
message string
static Lorg/apache/spark/util/LongAccumulator;.<clinit>()V
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
68
method Method
descriptor string
(Ljava/lang/String;)V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Error
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
21.0.9
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
324586415048
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
21.0.9
name string
java/lang

VirtualThreadEnd

experimental startTime duration stackTrace 19 21 25 26 27

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

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/events/VirtualThreadEndEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Experimental;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.MirrorEvent;

@Category("Java Application")
@Label("Virtual Thread End")
@Name("jdk.VirtualThreadEnd")
@MirrorEvent(className = "jdk.internal.event.VirtualThreadEndEvent")
@Experimental
public final class VirtualThreadEndEvent extends AbstractJDKEvent {

    @Label("Thread Id")
    public long javaThreadId;

}

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

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,

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 final static 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/java.base/share/classes/java/lang/VirtualThread.java:

        Object bindings = scopedValueBindings();
        try {
            runWith(bindings, task);
        } catch (Throwable exc) {
            dispatchUncaughtException(exc);
        } finally {
            try {
                // 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();
                }

            } finally {
                // last unmount
                if (notifyJvmti) notifyJvmtiUnmountBegin(true);
                unmount();

                // final state
                setState(TERMINATED);

Configuration enabled
profiling false
default false

Field Type Description
javaThreadId long Thread Id

FileRead

profiling default startTime duration stackTrace 11 17 21 25 26 27

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

Category: Java Application

Appearing in: SerialGC, ZGC

Missing in: G1GC, ParallelGC, ShenandoahGC

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/jdk.jfr/share/classes/jdk/jfr/events/EventConfigurations.java:

package jdk.jfr.events;
import jdk.jfr.internal.Utils;
import jdk.jfr.internal.event.EventConfiguration;

public final class EventConfigurations {
    public static final EventConfiguration SOCKET_READ = Utils.getConfiguration(SocketReadEvent.class);
    public static final EventConfiguration SOCKET_WRITE = Utils.getConfiguration(SocketWriteEvent.class);
    public static final EventConfiguration FILE_READ = Utils.getConfiguration(FileReadEvent.class);
    public static final EventConfiguration FILE_WRITE = Utils.getConfiguration(FileWriteEvent.class);
    public static final EventConfiguration FILE_FORCE = Utils.getConfiguration(FileForceEvent.class);
    public static final EventConfiguration ERROR_THROWN = Utils.getConfiguration(ErrorThrownEvent.class);
    public static final EventConfiguration EXCEPTION_THROWN = Utils.getConfiguration(ExceptionThrownEvent.class);
}

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

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.DataAmount;
import jdk.jfr.Name;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "FileRead")
@Label("File Read")
@Category("Java Application")
@Description("Reading data from a file")
public final class FileReadEvent extends AbstractJDKEvent {

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

    @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

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileInputStreamInstrumentor.java:

            if (result < 0) {
                endOfFile = true;
            } else {
                bytesRead = 1;
            }
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileReadEvent.commit(start, duration, path, bytesRead, endOfFile);
            }
        }
        return result;
    }

    @JIInstrumentationMethod
    public int read(byte b[]) throws IOException {

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileInputStreamInstrumentor.java:

        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            bytesRead = read(b);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                if (bytesRead < 0) {
                    FileReadEvent.commit(start, duration, path, 0L, true);
                } else {
                    FileReadEvent.commit(start, duration, path, bytesRead, false);
                }
            }
        }
        return bytesRead;
    }

    @JIInstrumentationMethod

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileInputStreamInstrumentor.java:

        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            bytesRead = read(b, off, len);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                if (bytesRead < 0) {
                    FileReadEvent.commit(start, duration, path, 0L, true);
                } else {
                    FileReadEvent.commit(start, duration, path, bytesRead, false);
                }
            }
        }
        return bytesRead;
    }
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/RandomAccessFileInstrumentor.java:

            if (result < 0) {
                endOfFile = true;
            } else {
                bytesRead = 1;
            }
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileReadEvent.commit(start, duration, path, bytesRead, endOfFile);
            }
        }
        return result;
    }

    @JIInstrumentationMethod
    public int read(byte b[]) throws IOException {

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/RandomAccessFileInstrumentor.java:

        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            bytesRead = read(b);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                if (bytesRead < 0) {
                    FileReadEvent.commit(start, duration, path, 0L, true);
                } else {
                    FileReadEvent.commit(start, duration, path, bytesRead, false);
                }
            }
        }
        return bytesRead;
    }

    @JIInstrumentationMethod

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/RandomAccessFileInstrumentor.java:

        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            bytesRead = read(b, off, len);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                if (bytesRead < 0) {
                    FileReadEvent.commit(start, duration, path, 0L, true);
                } else {
                    FileReadEvent.commit(start, duration, path, bytesRead, false);
                }
            }
        }
        return bytesRead;
    }

    @JIInstrumentationMethod

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileChannelImplInstrumentor.java:

        try {
            start = EventConfiguration.timestamp();
            bytesRead = read(dst);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                if (bytesRead < 0) {
                    FileReadEvent.commit(start, duration, path, 0L, true);
                } else {
                    FileReadEvent.commit(start, duration, path, bytesRead, false);
                }
            }
        }
        return bytesRead;
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileChannelImplInstrumentor.java:

        try {
            start = EventConfiguration.timestamp();
            bytesRead = read(dst, position);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                if (bytesRead < 0) {
                    FileReadEvent.commit(start, duration, path, 0L, true);
                } else {
                    FileReadEvent.commit(start, duration, path, bytesRead, false);
                }
            }
        }
        return bytesRead;
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileChannelImplInstrumentor.java:

        try {
            start = EventConfiguration.timestamp();
            bytesRead = read(dsts, offset, length);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                if (bytesRead < 0) {
                    FileReadEvent.commit(start, duration, path, 0L, true);
                } else {
                    FileReadEvent.commit(start, duration, path, bytesRead, false);
                }
            }
        }
        return bytesRead;
    }

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

        SecurityProviderServiceEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ExceptionThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ErrorThrownEvent.class,
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

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 2
bytesRead long: bytes
27935
endOfFile boolean
false
path string
/home/runner/work/jfrevents/jfrevents/harness-003916-17833306698725904421/apache-spark/als/blockmgr-f7fac2eb-c7cf-4f2a-9591-0f39ec4a6b4a/16/shuffle_12_137_0.data
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
162
lineNumber int
113
method Method
descriptor string
([BII)I
hidden boolean
false
modifiers int
1
name string
read
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/FileInputStream
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
21.0.9
name string
java/io
type FrameType
Inlined
truncated boolean
true
startTime long: millis
389966578659
bytesRead long: bytes
1
endOfFile boolean
false
path string
harness-003931-5537147875304790524/scala-dotty/dotty/out/scala/tools/scalap/scalax/rules/scalasig/AnnotatedWithSelfType.tasty
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
137
lineNumber int
66
method Method
descriptor string
()I
hidden boolean
false
modifiers int
1
name string
read
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/FileInputStream
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
21.0.9
name string
java/io
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
491828405582

VirtualThreadPinned

experimental profiling default startTime duration stackTrace 19 21 25 26 27

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

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/events/VirtualThreadPinnedEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Experimental;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.MirrorEvent;

@Category("Java Application")
@Label("Virtual Thread Pinned")
@Name("jdk.VirtualThreadPinned")
@MirrorEvent(className = "jdk.internal.event.VirtualThreadPinnedEvent")
@Experimental
public final class VirtualThreadPinnedEvent extends AbstractJDKEvent {
}

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

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,

src/java.base/share/classes/jdk/internal/event/VirtualThreadPinnedEvent.java:

package jdk.internal.event;

/**
 * Event recording that a virtual thread has parked on its carrier thread.
 */
public class VirtualThreadPinnedEvent extends Event {
}

src/java.base/share/classes/java/lang/VirtualThread.java:

    /**
     * Parks the current carrier thread up to the given waiting time or until
     * unparked or interrupted. If the virtual thread is interrupted then the
     * interrupt status will be propagated to the carrier thread.
     * @param timed true for a timed park, false for untimed
     * @param nanos the waiting time in nanoseconds
     */
    private void parkOnCarrierThread(boolean timed, long nanos) {
        assert state() == PARKING;

        var pinnedEvent = new VirtualThreadPinnedEvent();
        pinnedEvent.begin();

        setState(PINNED);
        try {
            if (!parkPermit) {
                if (!timed) {
                    U.park(false, 0);
                } else if (nanos > 0) {
                    U.park(false, nanos);
                }
            }

Configuration enabled stackTrace threshold
profiling true true 20 ms
default true true 20 ms

FileWrite

profiling default startTime duration stackTrace 11 17 21 25 26 27

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

Category: Java Application

Appearing in: G1GC, ParallelGC

Missing in: SerialGC, ShenandoahGC, ZGC

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/jdk.jfr/share/classes/jdk/jfr/events/FileWriteEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.DataAmount;
import jdk.jfr.Name;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "FileWrite")
@Label("File Write")
@Category("Java Application")
@Description("Writing data to a file")
public final class FileWriteEvent extends AbstractJDKEvent {

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

    @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

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

package jdk.jfr.events;
import jdk.jfr.internal.Utils;
import jdk.jfr.internal.event.EventConfiguration;

public final class EventConfigurations {
    public static final EventConfiguration SOCKET_READ = Utils.getConfiguration(SocketReadEvent.class);
    public static final EventConfiguration SOCKET_WRITE = Utils.getConfiguration(SocketWriteEvent.class);
    public static final EventConfiguration FILE_READ = Utils.getConfiguration(FileReadEvent.class);
    public static final EventConfiguration FILE_WRITE = Utils.getConfiguration(FileWriteEvent.class);
    public static final EventConfiguration FILE_FORCE = Utils.getConfiguration(FileForceEvent.class);
    public static final EventConfiguration ERROR_THROWN = Utils.getConfiguration(ErrorThrownEvent.class);
    public static final EventConfiguration EXCEPTION_THROWN = Utils.getConfiguration(ExceptionThrownEvent.class);
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/RandomAccessFileInstrumentor.java:

        if (!eventConfiguration.isEnabled()) {
            write(b);
            return;
        }
        long bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            write(b);
            bytesWritten = 1;
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileWriteEvent.commit(start, duration, path, bytesWritten);
            }
        }
    }

    @JIInstrumentationMethod
    public void write(byte b[]) throws IOException {
        EventConfiguration eventConfiguration = EventConfigurations.FILE_WRITE;
        if (!eventConfiguration.isEnabled()) {
            write(b);
            return;
        }
        long bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            write(b);
            bytesWritten = b.length;
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileWriteEvent.commit(start, duration, path, bytesWritten);
            }
        }
    }

    @JIInstrumentationMethod
    public void write(byte b[], int off, int len) throws IOException {
        EventConfiguration eventConfiguration = EventConfigurations.FILE_WRITE;
        if (!eventConfiguration.isEnabled()) {
            write(b, off, len);
            return;
        }
        long bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            write(b, off, len);
            bytesWritten = len;
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileWriteEvent.commit(start, duration, path, bytesWritten);
            }
        }
    }
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileChannelImplInstrumentor.java:

        EventConfiguration eventConfiguration = EventConfigurations.FILE_WRITE;
        if (!eventConfiguration.isEnabled()) {
            return write(src);
        }
        int bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            bytesWritten = write(src);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                long bytes = bytesWritten > 0 ? bytesWritten : 0;
                FileWriteEvent.commit(start, duration, path, bytes);
            }
        }
        return bytesWritten;
    }

    @JIInstrumentationMethod
    public int write(ByteBuffer src, long position) throws IOException {
        EventConfiguration eventConfiguration = EventConfigurations.FILE_WRITE;
        if (!eventConfiguration.isEnabled()) {
            return write(src, position);
        }

        int bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            bytesWritten = write(src, position);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                long bytes = bytesWritten > 0 ? bytesWritten : 0;
                FileWriteEvent.commit(start, duration, path, bytes);
            }
        }
        return bytesWritten;
    }

    @JIInstrumentationMethod
    public long write(ByteBuffer[] srcs, int offset, int length) throws IOException {
        EventConfiguration eventConfiguration = EventConfigurations.FILE_WRITE;
        if (!eventConfiguration.isEnabled()) {
            return write(srcs, offset, length);
        }
        long bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            bytesWritten = write(srcs, offset, length);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                long bytes = bytesWritten > 0 ? bytesWritten : 0;
                FileWriteEvent.commit(start, duration, path, bytes);
            }
        }
        return bytesWritten;
    }
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileOutputStreamInstrumentor.java:

        if (!eventConfiguration.isEnabled()) {
            write(b);
            return;
        }
        long bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            write(b);
            bytesWritten = 1;
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileWriteEvent.commit(start, duration, path, bytesWritten);
            }
        }
    }

    @JIInstrumentationMethod
    public void write(byte b[]) throws IOException {
        EventConfiguration eventConfiguration = EventConfigurations.FILE_WRITE;
        if (!eventConfiguration.isEnabled()) {
            write(b);
            return;
        }
        long bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            write(b);
            bytesWritten = b.length;
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileWriteEvent.commit(start, duration, path, bytesWritten);
            }
        }
    }

    @JIInstrumentationMethod
    public void write(byte b[], int off, int len) throws IOException {
        EventConfiguration eventConfiguration = EventConfigurations.FILE_WRITE;
        if (!eventConfiguration.isEnabled()) {
            write(b, off, len);
            return;
        }
        long bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            write(b, off, len);
            bytesWritten = len;
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileWriteEvent.commit(start, duration, path, bytesWritten);
            }
        }
    }
}

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

        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ExceptionThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ErrorThrownEvent.class,
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.SecurityProviderServiceEvent.class,

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

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 2
bytesWritten long: bytes
85805
path string
/home/runner/work/jfrevents/jfrevents/harness-003928-7951762178349451551/apache-spark/als/blockmgr-2bb2e5d4-fda1-4c72-8c69-c810458aa118/3e/shuffle_6_202_0.data.aecc1fe2-0c0f-4b5c-b06a-c169419e5048
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
678
lineNumber int
154
method Method
descriptor string
(Ljava/nio/ByteBuffer;)I
hidden boolean
false
modifiers int
1
name string
write
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/nio/ch/FileChannelImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
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location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
sun/nio/ch
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
398117182764
bytesWritten long: bytes
28112
path string
/home/runner/work/jfrevents/jfrevents/harness-003927-11018005009666797249/apache-spark/als/blockmgr-8e66d520-4bed-4a10-a35a-3b794a9b4dcb/33/temp_shuffle_d4341960-d619-437f-9c2b-0dfb3ad1ef14
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
171
lineNumber int
103
method Method
descriptor string
([BII)V
hidden boolean
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modifiers int
1
name string
write
type Class
classLoader ClassLoader
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bootstrap
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null
hidden boolean
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modifiers int
1
name string
java/io/FileOutputStream
package Package
exported boolean
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module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
java/io
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
302040747617

SocketWrite

profiling default startTime duration stackTrace 11 17 21 25 26 27

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

Category: Java Application

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/jdk.jfr/share/classes/jdk/jfr/events/SocketWriteEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.DataAmount;
import jdk.jfr.Name;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "SocketWrite")
@Label("Socket Write")
@Category("Java Application")
@Description("Writing data to a socket")
public final class SocketWriteEvent extends AbstractJDKEvent {

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

    @Label("Remote Host")
    public String host;

    @Label("Remote Address")
    public String address;

    @Label("Remote Port")

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

package jdk.jfr.events;
import jdk.jfr.internal.Utils;
import jdk.jfr.internal.event.EventConfiguration;

public final class EventConfigurations {
    public static final EventConfiguration SOCKET_READ = Utils.getConfiguration(SocketReadEvent.class);
    public static final EventConfiguration SOCKET_WRITE = Utils.getConfiguration(SocketWriteEvent.class);
    public static final EventConfiguration FILE_READ = Utils.getConfiguration(FileReadEvent.class);
    public static final EventConfiguration FILE_WRITE = Utils.getConfiguration(FileWriteEvent.class);
    public static final EventConfiguration FILE_FORCE = Utils.getConfiguration(FileForceEvent.class);
    public static final EventConfiguration ERROR_THROWN = Utils.getConfiguration(ErrorThrownEvent.class);
    public static final EventConfiguration EXCEPTION_THROWN = Utils.getConfiguration(ExceptionThrownEvent.class);
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/SocketChannelImplInstrumentor.java:

            bytesWritten = write(buf);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                long bytes = bytesWritten < 0 ? 0 : bytesWritten;
                SocketAddress remoteAddress = getRemoteAddress();
                if (remoteAddress instanceof InetSocketAddress isa) {
                    String hostString  = isa.getAddress().toString();
                    int delimiterIndex = hostString.lastIndexOf('/');

                    String host = hostString.substring(0, delimiterIndex);
                    String address = hostString.substring(delimiterIndex + 1);
                    int port = isa.getPort();
                    SocketWriteEvent.commit(start, duration, host, address, port, bytes);
                } else {
                    UnixDomainSocketAddress udsa = (UnixDomainSocketAddress) remoteAddress;
                    String path = "[" + udsa.getPath().toString() + "]";
                    SocketWriteEvent.commit(start, duration, "Unix domain socket", path, 0, bytes);
                }
            }
        }
        return bytesWritten;
    }

    public SocketAddress getRemoteAddress() throws IOException {
        // gets replaced by call to instrumented class
        return null;
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/SocketChannelImplInstrumentor.java:

            bytesWritten = write(srcs, offset, length);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                long bytes = bytesWritten < 0 ? 0 : bytesWritten;
                SocketAddress remoteAddress = getRemoteAddress();
                if (remoteAddress instanceof InetSocketAddress isa) {
                    String hostString  = isa.getAddress().toString();
                    int delimiterIndex = hostString.lastIndexOf('/');

                    String host = hostString.substring(0, delimiterIndex);
                    String address = hostString.substring(delimiterIndex + 1);
                    int port = isa.getPort();
                    SocketWriteEvent.commit(start, duration, host, address, port, bytes);
                } else {
                    UnixDomainSocketAddress udsa = (UnixDomainSocketAddress) remoteAddress;
                    String path = "[" + udsa.getPath().toString() + "]";
                    SocketWriteEvent.commit(start, duration, "Unix domain socket", path, 0, bytes);
                }
            }
        }
        return bytesWritten;
    }
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/SocketOutputStreamInstrumentor.java:

            write(b, off, len);
            return;
        }
        int bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            write(b, off, len);
            bytesWritten = len;
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                InetAddress remote = parent.getInetAddress();
                SocketWriteEvent.commit(
                        start,
                        duration,
                        remote.getHostName(),
                        remote.getHostAddress(),
                        parent.getPort(),
                        bytesWritten);
            }
        }
    }

    // private field in java.net.Socket$SocketOutputStream

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

        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ExceptionThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ErrorThrownEvent.class,
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.SecurityProviderServiceEvent.class,
        jdk.internal.event.ThreadSleepEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

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

JavaExceptionThrow

startTime duration stackTrace 11 17 21 25 26 27

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

Category: Java Application

An object derived from java.lang.Exception has been created

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
message string Message
thrownClass Class Class

Examples 3
message string
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
30
lineNumber int
259
method Method
descriptor string
()V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Throwable
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
21.0.9
name string
java/lang
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
375255085054
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/EOFException
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
21.0.9
name string
java/io
message string
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
30
lineNumber int
259
method Method
descriptor string
()V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Throwable
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
21.0.9
name string
java/lang
type FrameType
Inlined
truncated boolean
true
startTime long: millis
366280592450
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/EOFException
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
21.0.9
name string
java/io
message string
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
30
lineNumber int
259
method Method
descriptor string
()V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Throwable
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
21.0.9
name string
java/lang
type FrameType
Inlined
truncated boolean
true
startTime long: millis
278765123745
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/EOFException
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
21.0.9
name string
java/io

Java Application Statistics

JavaThreadStatistics

profiling default startTime duration every chunk 11 17 21 25 26 27 graal vm

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:

 *
 *  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) {
  u8 totalPhysicalMemory = os::physical_memory();
  EventPhysicalMemory event;
  event.set_totalSize(totalPhysicalMemory);
  event.set_usedSize(totalPhysicalMemory - os::available_memory());
  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(ClassLoadingStatistics) {
#if INCLUDE_MANAGEMENT
  EventClassLoadingStatistics event;
  event.set_loadedClassCount(ClassLoadingService::loaded_class_count());

Configuration enabled period
profiling true 1000 ms
default true 1000 ms

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
accumulatedCount long
1853
activeCount long
46
daemonCount long
45
peakCount long
278
startTime long: millis
470963245601
accumulatedCount long
1650
activeCount long
97
daemonCount long
96
peakCount long
287
startTime long: millis
333372880087
accumulatedCount long
1341
activeCount long
40
daemonCount long
39
peakCount long
272
startTime long: millis
445908605188

ClassLoadingStatistics

profiling default startTime duration every chunk 11 17 21 25 26 27 graal vm

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:

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(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(NULL) {}

Configuration enabled period
profiling true 1000 ms
default true 1000 ms

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
loadedClassCount long
122062
startTime long: millis
343491871442
unloadedClassCount long
3227
loadedClassCount long
123757
startTime long: millis
460815248449
unloadedClassCount long
4663
loadedClassCount long
95138
startTime long: millis
428616035250
unloadedClassCount long
2376

ClassLoaderStatistics

profiling default startTime duration every chunk 11 17 21 25 26 27

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:

  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(NULL) {}

  bool do_entry(oop const& key, ClassLoaderStats const& cls) {
    const ClassLoaderData* this_cld = cls._class_loader != NULL ?
      java_lang_ClassLoader::loader_data_acquire(cls._class_loader) : NULL;
    const ClassLoaderData* parent_cld = cls._parent != NULL ?
      java_lang_ClassLoader::loader_data_acquire(cls._parent) : NULL;
    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;

Configuration enabled period
profiling true everyChunk
default true everyChunk

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
blockSize ulong: bytes
3176
chunkSize ulong: bytes
4096
classCount long
1
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
jdk/internal/reflect/DelegatingClassLoader
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
21.0.9
name string
jdk/internal/reflect
classLoaderData ulong: address
140018453544272
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
21.0.9
name string
java/net
startTime long: millis
278182142799
blockSize ulong: bytes
3440
chunkSize ulong: bytes
4096
classCount long
1
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
jdk/internal/reflect/DelegatingClassLoader
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
21.0.9
name string
jdk/internal/reflect
classLoaderData ulong: address
140430612565248
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
21.0.9
name string
java/net
startTime long: millis
378912624594
blockSize ulong: bytes
3320
chunkSize ulong: bytes
6144
classCount long
1
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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
0
name string
org/neo4j/codegen/CodeLoader
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
org/neo4j/codegen
classLoaderData ulong: address
139843208465728
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
21.0.9
name string
java/net
startTime long: millis
371359375252

ThreadAllocationStatistics

profiling default startTime every chunk 11 17 21 25 26 27

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<jlong> 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 != NULL, "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:
 *

Configuration enabled period
profiling true everyChunk
default true everyChunk

Field Type Description
allocated ulong: bytes Allocated Approximate number of bytes allocated since thread start
thread Thread Thread

Examples 3
allocated ulong: bytes
128
startTime long: millis
278185390348
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
RxCachedWorkerPoolEvictor-1
javaThreadId long
807
osName string
RxCachedWorkerPoolEvictor-1
osThreadId long
3296
virtual boolean
false
allocated ulong: bytes
25064
startTime long: millis
371363060942
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
SparkUI-1150
javaThreadId long
1150
osName string
SparkUI-1150
osThreadId long
4380
virtual boolean
false
allocated ulong: bytes
51376
startTime long: millis
378913010243
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
RemoteBlock-temp-file-clean-thread
javaThreadId long
1134
osName string
RemoteBlock-temp-file-clean-thread
osThreadId long
3721
virtual boolean
false

FinalizerStatistics

profiling default startTime end of every chunk 18 21 25 26 27

Category: Java Application / Statistics

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 != NULL, "invariant");
  assert(ik->has_finalizer(), "invariant");
  assert(thread != NULL, "invariant");
  const char* const url = fe != nullptr ? fe->codesource() : nullptr;
  const traceid url_symbol_id = url != NULL ? 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 == NULL) {
    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:

Configuration enabled period
profiling true endChunk
default true endChunk

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
codeSource Symbol
file:///home/runner/work/jfrevents/jfrevents/harness-003927-11018005009666797249/twitter-finagle/lib/finagle-netty4_2.13-22.12.0.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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
1
name string
com/twitter/finagle/netty4/HashedWheelTimer
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
com/twitter/finagle/netty4
objects ulong
1
startTime long: millis
282992929523
totalFinalizersRun ulong
0
codeSource Symbol
file:///home/runner/work/jfrevents/jfrevents/harness-003928-7951762178349451551/apache-spark/lib/netty-buffer-4.1.99.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
21.0.9
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/buffer
objects ulong
16
startTime long: millis
374807905603
totalFinalizersRun ulong
0
codeSource Symbol
file:///home/runner/work/jfrevents/jfrevents/harness-003916-17833306698725904421/apache-spark/lib/spark-core_2.13-3.5.0.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
21.0.9
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/sparkproject/jetty/util/resource/JarFileResource
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
org/sparkproject/jetty/util/resource
objects ulong
4
startTime long: millis
382717854734
totalFinalizersRun ulong
0

ExceptionStatistics

profiling default startTime duration stackTrace 11 17 21 25 26 27

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/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.StackTrace;
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")
@StackTrace(false)
public final class ExceptionStatisticsEvent extends AbstractJDKEvent {

    @Label("Exceptions Created")
    public long throwables;
}

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

        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ExceptionThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ErrorThrownEvent.class,
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.SecurityProviderServiceEvent.class,
        jdk.internal.event.ThreadSleepEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.VirtualThreadStartEvent.class,
        jdk.internal.event.VirtualThreadEndEvent.class,

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

    private static boolean initializationTriggered;

    @SuppressWarnings("unchecked")
    public static synchronized void initialize() {
        try {
            if (initializationTriggered == false) {
                for (Class<?> mirrorEventClass : mirrorEventClasses) {
                    SecuritySupport.registerMirror(((Class<? extends Event>)mirrorEventClass));
                }
                for (Class<?> eventClass : eventClasses) {
                    SecuritySupport.registerEvent((Class<? extends Event>) eventClass);
                }

                RequestEngine.addTrustedJDKHook(ExceptionStatisticsEvent.class, emitExceptionStatistics);
                RequestEngine.addTrustedJDKHook(DirectBufferStatisticsEvent.class, emitDirectBufferStatistics);
                RequestEngine.addTrustedJDKHook(InitialSecurityPropertyEvent.class, emitInitialSecurityProperties);

                initializeContainerEvents();
                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/instrument/JDKEvents.java:

        SecuritySupport.registerEvent(ContainerCPUUsageEvent.class);
        SecuritySupport.registerEvent(ContainerCPUThrottlingEvent.class);
        SecuritySupport.registerEvent(ContainerMemoryUsageEvent.class);
        SecuritySupport.registerEvent(ContainerIOUsageEvent.class);

        RequestEngine.addTrustedJDKHook(ContainerConfigurationEvent.class, emitContainerConfiguration);
        RequestEngine.addTrustedJDKHook(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        RequestEngine.addTrustedJDKHook(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        RequestEngine.addTrustedJDKHook(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        RequestEngine.addTrustedJDKHook(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void emitExceptionStatistics() {
        ExceptionStatisticsEvent t = new ExceptionStatisticsEvent();
        t.throwables = ThrowableTracer.numThrowables();
        t.commit();
    }

    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();

Configuration enabled period
profiling true 1000 ms
default true 1000 ms

Field Type Description
throwables long Exceptions Created

Examples 3
stackTrace StackTrace
null
startTime long: millis
452304103056
throwables long
2217762
stackTrace StackTrace
null
startTime long: millis
434192247982
throwables long
2205351
stackTrace StackTrace
null
startTime long: millis
308375495850
throwables long
2203021

DirectBufferStatistics

profiling default startTime duration stackTrace 15 17 21 25 26 27

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/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;
}

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

        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.SecurityProviderServiceEvent.class,
        jdk.internal.event.ThreadSleepEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.VirtualThreadStartEvent.class,
        jdk.internal.event.VirtualThreadEndEvent.class,
        jdk.internal.event.VirtualThreadPinnedEvent.class,
        jdk.internal.event.VirtualThreadSubmitFailedEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,

        DirectBufferStatisticsEvent.class,
        InitialSecurityPropertyEvent.class,
    };

    // This is a list of the classes with instrumentation code that should be applied.
    private static final Class<?>[] instrumentationClasses = new Class<?>[] {
        FileInputStreamInstrumentor.class,
        FileOutputStreamInstrumentor.class,
        RandomAccessFileInstrumentor.class,
        FileChannelImplInstrumentor.class,
        SocketInputStreamInstrumentor.class,
        SocketOutputStreamInstrumentor.class,

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

    @SuppressWarnings("unchecked")
    public static synchronized void initialize() {
        try {
            if (initializationTriggered == false) {
                for (Class<?> mirrorEventClass : mirrorEventClasses) {
                    SecuritySupport.registerMirror(((Class<? extends Event>)mirrorEventClass));
                }
                for (Class<?> eventClass : eventClasses) {
                    SecuritySupport.registerEvent((Class<? extends Event>) eventClass);
                }

                RequestEngine.addTrustedJDKHook(ExceptionStatisticsEvent.class, emitExceptionStatistics);
                RequestEngine.addTrustedJDKHook(DirectBufferStatisticsEvent.class, emitDirectBufferStatistics);
                RequestEngine.addTrustedJDKHook(InitialSecurityPropertyEvent.class, emitInitialSecurityProperties);

                initializeContainerEvents();
                initializationTriggered = true;
            }
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not initialize JDK events. " + e.getMessage());
        }
    }

    public static void addInstrumentation() {

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

    public static void remove() {
        RequestEngine.removeHook(emitExceptionStatistics);
        RequestEngine.removeHook(emitDirectBufferStatistics);
        RequestEngine.removeHook(emitInitialSecurityProperties);

        RequestEngine.removeHook(emitContainerConfiguration);
        RequestEngine.removeHook(emitContainerCPUUsage);
        RequestEngine.removeHook(emitContainerCPUThrottling);
        RequestEngine.removeHook(emitContainerMemoryUsage);
        RequestEngine.removeHook(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();

Configuration enabled period
profiling true 5 s
default true 5 s

Examples 3
stackTrace StackTrace
null
startTime long: millis
481152694838
stackTrace StackTrace
null
startTime long: millis
363560804422
stackTrace StackTrace
null
startTime long: millis
439466330871

Java Development Kit

InitialSecurityProperty

profiling default startTime duration stackTrace 17 21 25 26 27

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/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 AbstractJDKEvent {
    @Label("Key")
    public String key;

    @Label("Value")
    public String value;
}

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

        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.SecurityProviderServiceEvent.class,
        jdk.internal.event.ThreadSleepEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.VirtualThreadStartEvent.class,
        jdk.internal.event.VirtualThreadEndEvent.class,
        jdk.internal.event.VirtualThreadPinnedEvent.class,
        jdk.internal.event.VirtualThreadSubmitFailedEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,

        DirectBufferStatisticsEvent.class,
        InitialSecurityPropertyEvent.class,
    };

    // This is a list of the classes with instrumentation code that should be applied.
    private static final Class<?>[] instrumentationClasses = new Class<?>[] {
        FileInputStreamInstrumentor.class,
        FileOutputStreamInstrumentor.class,
        RandomAccessFileInstrumentor.class,
        FileChannelImplInstrumentor.class,
        SocketInputStreamInstrumentor.class,
        SocketOutputStreamInstrumentor.class,
        SocketChannelImplInstrumentor.class

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

    @SuppressWarnings("unchecked")
    public static synchronized void initialize() {
        try {
            if (initializationTriggered == false) {
                for (Class<?> mirrorEventClass : mirrorEventClasses) {
                    SecuritySupport.registerMirror(((Class<? extends Event>)mirrorEventClass));
                }
                for (Class<?> eventClass : eventClasses) {
                    SecuritySupport.registerEvent((Class<? extends Event>) eventClass);
                }

                RequestEngine.addTrustedJDKHook(ExceptionStatisticsEvent.class, emitExceptionStatistics);
                RequestEngine.addTrustedJDKHook(DirectBufferStatisticsEvent.class, emitDirectBufferStatistics);
                RequestEngine.addTrustedJDKHook(InitialSecurityPropertyEvent.class, emitInitialSecurityProperties);

                initializeContainerEvents();
                initializationTriggered = true;
            }
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not initialize JDK events. " + e.getMessage());
        }
    }

    public static void addInstrumentation() {
        try {

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

        RequestEngine.removeHook(emitContainerConfiguration);
        RequestEngine.removeHook(emitContainerCPUUsage);
        RequestEngine.removeHook(emitContainerCPUThrottling);
        RequestEngine.removeHook(emitContainerMemoryUsage);
        RequestEngine.removeHook(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();
            }
        }
    }
}

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
key string Key
value string Value

Examples 3
key string
jdk.tls.disabledAlgorithms
stackTrace StackTrace
null
startTime long: millis
278345740049
value string
SSLv3, TLSv1, TLSv1.1, DTLSv1.0, RC4, DES, MD5withRSA, DH keySize < 1024, EC keySize < 224, 3DES_EDE_CBC, anon, NULL, ECDH
key string
jdk.tls.keyLimits
stackTrace StackTrace
null
startTime long: millis
388495919301
value string
AES/GCM/NoPadding KeyUpdate 2^37, ChaCha20-Poly1305 KeyUpdate 2^37
key string
jdk.includeInExceptions
stackTrace StackTrace
null
startTime long: millis
371521701971
value string
hostInfo,jar

VirtualThreadSubmitFailed

experimental profiling default startTime duration stackTrace 19 21 25 26 27

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/jdk.jfr/share/classes/jdk/jfr/events/VirtualThreadSubmitFailedEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Experimental;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.MirrorEvent;

@Category({"Java Development Kit", "Threading"})
@Label("Virtual Thread Submit Failed")
@Name("jdk.VirtualThreadSubmitFailed")
@Description("Submit of task for virtual thread failed")
@MirrorEvent(className = "jdk.internal.event.VirtualThreadSubmitFailedEvent")
@Experimental
public final class VirtualThreadSubmitFailedEvent extends AbstractJDKEvent {

    @Label("Thread Id")
    public long javaThreadId;

    @Label("Exception Message")
    public String exceptionMessage;

}

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

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ExceptionThrownEvent.class,

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/java.base/share/classes/java/lang/VirtualThread.java:

     * @throws RejectedExecutionException
     * @see ForkJoinPool#externalSubmit(ForkJoinTask)
     */
    private void externalSubmitRunContinuation(ForkJoinPool pool) {
        try {
            pool.externalSubmit(ForkJoinTask.adapt(runContinuation));
        } catch (RejectedExecutionException ree) {
            submitFailed(ree);
            throw ree;
        }
    }

    /**
     * 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. The virtual thread is
     * mounted on the current (carrier) thread before the task runs. It unmounts
     * from its carrier thread when the task completes.

Configuration enabled stackTrace
profiling true true
default true true

Field Type Description
javaThreadId long Thread Id
exceptionMessage string Exception Message

X509Validation

startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/X509ValidationEvent.java

Category: Java Development Kit / Security

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/jdk.jfr/share/classes/jdk/jfr/events/X509ValidationEvent.java:

package jdk.jfr.events;

import jdk.jfr.*;
import jdk.jfr.internal.MirrorEvent;

@Category({"Java Development Kit", "Security"})
@Label("X509 Validation")
@Name("jdk.X509Validation")
@Description("Serial numbers from X.509 Certificates forming chain of trust")
@MirrorEvent(className = "jdk.internal.event.X509ValidationEvent")
public final class X509ValidationEvent extends AbstractJDKEvent {
    @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;
}

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

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ExceptionThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ErrorThrownEvent.class,

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

Configuration enabled stackTrace
profiling false true
default false true

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

SecurityProviderService

startTime duration stackTrace 11 17 21 25 26 27

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

Category: Java Development Kit / Security

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/jdk.jfr/share/classes/jdk/jfr/events/SecurityProviderServiceEvent.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;

@Category({"Java Development Kit", "Security"})
@Label("Security Provider Instance Request")
@Name("jdk.SecurityProviderService")
@Description("Details of Provider.getInstance(String type, String algorithm) calls")
@MirrorEvent(className = "jdk.internal.event.SecurityProviderServiceEvent")
public final class SecurityProviderServiceEvent extends AbstractJDKEvent {
    @Label("Type of Service")
    public String type;

    @Label("Algorithm Name")
    public String algorithm;

    @Label("Security Provider")
    public String provider;
}

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

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {

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 final static 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/java.base/share/classes/java/security/Provider.java:

        if (!key.matches(type, algorithm)) {
            key = new ServiceKey(type, algorithm, false);
            previousKey = key;
        }

        Service s = serviceMap.get(key);
        if (s == null) {
            s = legacyMap.get(key);
            if (s != null && !s.isValid()) {
                legacyMap.remove(key, s);
            }
        }

        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

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
type string Type of Service
algorithm string Algorithm Name
provider string Security Provider

Examples 3
algorithm string
SHA
provider string
SUN
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
138
lineNumber int
1301
method Method
descriptor string
(Ljava/lang/String;Ljava/lang/String;)Ljava/security/Provider$Service;
hidden boolean
false
modifiers int
1
name string
getService
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/security/Provider
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
java/security
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
324568760045
type string
MessageDigest
algorithm string
SHA
provider string
SUN
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
138
lineNumber int
1301
method Method
descriptor string
(Ljava/lang/String;Ljava/lang/String;)Ljava/security/Provider$Service;
hidden boolean
false
modifiers int
1
name string
getService
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/security/Provider
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
21.0.9
name string
java/security
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
442821598968
type string
MessageDigest
algorithm string
SHA
provider string
SUN
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
138
lineNumber int
1301
method Method
descriptor string
(Ljava/lang/String;Ljava/lang/String;)Ljava/security/Provider$Service;
hidden boolean
false
modifiers int
1
name string
getService
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/security/Provider
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
21.0.9
name string
java/security
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
449164779428
type string
MessageDigest

Deserialization

startTime duration stackTrace 11 17 21 25 26 27

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

Category: Java Development Kit / Serialization

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/jdk.jfr/share/classes/jdk/jfr/events/DeserializationEvent.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;

@Category({"Java Development Kit", "Serialization"})
@Label("Deserialization")
@Name("jdk.Deserialization")
@Description("Results of deserialization and ObjectInputFilter checks")
@MirrorEvent(className = "jdk.internal.event.DeserializationEvent")
public final class DeserializationEvent extends AbstractJDKEvent {

    @Label("Filter Configured")
    public boolean filterConfigured;

    @Label("Filter Status")
    public String filterStatus;

    @Label ("Type")
    public Class<?> type;

    @Label ("Array Length")

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

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class

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/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;
}

Configuration enabled stackTrace
profiling false true
default false true

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
arrayLength int
-1
bytesRead long
41056
depth long
46
exceptionMessage string
null
exceptionType Class
null
filterConfigured boolean
false
filterStatus string
null
objectReferences long
1868
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
304
lineNumber int
1436
method Method
descriptor string
(Ljava/lang/Class;I)V
hidden boolean
false
modifiers int
2
name string
filterCheck
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/ObjectInputStream
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
21.0.9
name string
java/io
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
374276522114
type Class
null
arrayLength int
10
bytesRead long
47903
depth long
3
exceptionMessage string
null
exceptionType Class
null
filterConfigured boolean
false
filterStatus string
null
objectReferences long
964
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
304
lineNumber int
1436
method Method
descriptor string
(Ljava/lang/Class;I)V
hidden boolean
false
modifiers int
2
name string
filterCheck
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/ObjectInputStream
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
21.0.9
name string
java/io
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
366275098562
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[F
package Package
null
arrayLength int
-1
bytesRead long
74999
depth long
3
exceptionMessage string
null
exceptionType Class
null
filterConfigured boolean
false
filterStatus string
null
objectReferences long
1506
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
304
lineNumber int
1436
method Method
descriptor string
(Ljava/lang/Class;I)V
hidden boolean
false
modifiers int
2
name string
filterCheck
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/ObjectInputStream
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
21.0.9
name string
java/io
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
275178143386
type Class
null

X509Certificate

startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/X509CertificateEvent.java

Category: Java Development Kit / Security

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/jdk.jfr/share/classes/jdk/jfr/events/X509CertificateEvent.java:

package jdk.jfr.events;

import jdk.jfr.*;
import jdk.jfr.internal.MirrorEvent;

@Category({"Java Development Kit", "Security"})
@Label("X509 Certificate")
@Name("jdk.X509Certificate")
@Description("Details of X.509 Certificate parsed by JDK")
@MirrorEvent(className = "jdk.internal.event.X509CertificateEvent")
public final class X509CertificateEvent extends AbstractJDKEvent {
    @Label("Signature Algorithm")
    public String algorithm;

    @Label("Serial Number")
    public String serialNumber;

    @Label("Subject")
    public String subject;

    @Label("Issuer")
    public String issuer;

    @Label("Key Type")

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

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ExceptionThrownEvent.class,
        ExceptionStatisticsEvent.class,

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 = x509.getSerialNumber().toString(16);
            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();
            }

Configuration enabled stackTrace
profiling false true
default false true

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
algorithm string
SHA1withDSA
certificateId ulong: certificateId
3045411335
issuer string
CN=Unknown, OU=Unknown, O=Unknown, L=Unknown, ST=Unknown, C=Unknown
keyLength int
1024
keyType string
DSA
serialNumber string
46:10:1f:71
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
185
lineNumber int
128
method Method
descriptor string
(Ljava/security/cert/Certificate;)V
hidden boolean
false
modifiers int
9
name string
tryCommitCertEvent
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
sun/security/jca/JCAUtil
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
21.0.9
name string
sun/security/jca
type FrameType
Interpreted
truncated boolean
true
startTime long: millis
443546144400
subject string
CN=Unknown, OU=Unknown, O=Unknown, L=Unknown, ST=Unknown, C=Unknown
validFrom long: epochmillis
1175461745000
validUntil long: epochmillis
4329061745000
algorithm string
SHA1withDSA
certificateId ulong: certificateId
3045411335
issuer string
CN=Unknown, OU=Unknown, O=Unknown, L=Unknown, ST=Unknown, C=Unknown
keyLength int
1024
keyType string
DSA
serialNumber string
46:10:1f:71
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
185
lineNumber int
128
method Method
descriptor string
(Ljava/security/cert/Certificate;)V
hidden boolean
false
modifiers int
9
name string
tryCommitCertEvent
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
sun/security/jca/JCAUtil
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
21.0.9
name string
sun/security/jca
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
323674348680
subject string
CN=Unknown, OU=Unknown, O=Unknown, L=Unknown, ST=Unknown, C=Unknown
validFrom long: epochmillis
1175461745000
validUntil long: epochmillis
4329061745000
algorithm string
SHA1withDSA
certificateId ulong: certificateId
3045411335
issuer string
CN=Unknown, OU=Unknown, O=Unknown, L=Unknown, ST=Unknown, C=Unknown
keyLength int
1024
keyType string
DSA
serialNumber string
46:10:1f:71
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
185
lineNumber int
128
method Method
descriptor string
(Ljava/security/cert/Certificate;)V
hidden boolean
false
modifiers int
9
name string
tryCommitCertEvent
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
sun/security/jca/JCAUtil
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
21.0.9
name string
sun/security/jca
type FrameType
Interpreted
truncated boolean
true
startTime long: millis
449306982013
subject string
CN=Unknown, OU=Unknown, O=Unknown, L=Unknown, ST=Unknown, C=Unknown
validFrom long: epochmillis
1175461745000
validUntil long: epochmillis
4329061745000

TLSHandshake

startTime duration stackTrace 11 17 21 25 26 27

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

Category: Java Development Kit / Security

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/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")
@MirrorEvent(className = "jdk.internal.event.TLSHandshakeEvent")
public final class TLSHandshakeEvent extends AbstractJDKEvent {
    @Label("Peer Host")
    public String peerHost;

    @Label("Peer Port")
    public int peerPort;

    @Label("Protocol Version")
    public String protocolVersion;

    @Label("Cipher Suite")
    public String cipherSuite;

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

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,

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:

            // May need to retransmit the last flight for DTLS.
            if (!shc.sslContext.isDTLS()) {
                shc.conContext.finishHandshake();
            }
            recordEvent(shc.conContext.conSession);

            //
            // produce
            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);

Configuration enabled stackTrace
profiling false true
default false true

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

SecurityPropertyModification

startTime duration stackTrace 11 17 21 25 26 27

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

Category: Java Development Kit / Security

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/jdk.jfr/share/classes/jdk/jfr/events/SecurityPropertyModificationEvent.java:

package jdk.jfr.events;

import jdk.jfr.*;
import jdk.jfr.internal.MirrorEvent;

@Category({"Java Development Kit", "Security"})
@Label("Security Property Modification")
@Name("jdk.SecurityPropertyModification")
@Description("Modification of Security property")
@MirrorEvent(className = "jdk.internal.event.SecurityPropertyModificationEvent")
public final class SecurityPropertyModificationEvent extends AbstractJDKEvent {
    @Label("Key")
    public String key;

    @Label("Value")
    public String value;
}

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

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

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/java.base/share/classes/java/security/Security.java:

     *          if a security manager exists and its {@link
     *          java.lang.SecurityManager#checkPermission} method
     *          denies access to set the specified security property value
     * @throws  NullPointerException if key or datum is {@code null}
     *
     * @see #getProperty
     * @see java.security.SecurityPermission
     */
    public static void setProperty(String key, String datum) {
        check("setProperty." + key);
        props.put(key, datum);
        invalidateSMCache(key);  /* See below. */

        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);
        }
    }

    /*

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
key string Key
value string Value

Operating System

OSInformation

profiling default startTime duration end of every chunk 11 17 21 25 26 27 graal vm

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:

  event.set_jvmVersion(VM_Version::internal_vm_info_string());
  event.set_javaArguments(Arguments::java_command());
  event.set_jvmArguments(Arguments::jvm_args());
  event.set_jvmFlags(Arguments::jvm_flags());
  event.set_jvmStartTime(Management::vm_init_done_time());
  event.set_pid(os::current_process_id());
  event.commit();
 }

TRACE_REQUEST_FUNC(OSInformation) {
  ResourceMark rm;
  char* os_name = NEW_RESOURCE_ARRAY(char, 2048);
  JfrOSInterface::os_version(&os_name);
  EventOSInformation event;
  event.set_osVersion(os_name);
  event.commit();
}

TRACE_REQUEST_FUNC(VirtualizationInformation) {
  EventVirtualizationInformation event;
  event.set_name(JfrOSInterface::virtualization_name());
  event.commit();
}

TRACE_REQUEST_FUNC(ModuleRequire) {

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
osVersion string OS Version

Examples 3
osVersion string
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=24.04 DISTRIB_CODENAME=noble DISTRIB_DESCRIPTION="Ubuntu 24.04.3 LTS" uname: Linux 6.11.0-1018-azure #18~24.04.1-Ubuntu SMP Sat Jun 28 04:46:03 UTC 2025 x86_64 libc: glibc 2.39 NPTL 2.39
startTime long: millis
433004617341
osVersion string
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=24.04 DISTRIB_CODENAME=noble DISTRIB_DESCRIPTION="Ubuntu 24.04.3 LTS" uname: Linux 6.11.0-1018-azure #18~24.04.1-Ubuntu SMP Sat Jun 28 04:46:03 UTC 2025 x86_64 libc: glibc 2.39 NPTL 2.39
startTime long: millis
470672556817
osVersion string
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=24.04 DISTRIB_CODENAME=noble DISTRIB_DESCRIPTION="Ubuntu 24.04.3 LTS" uname: Linux 6.11.0-1018-azure #18~24.04.1-Ubuntu SMP Sat Jun 28 04:46:03 UTC 2025 x86_64 libc: glibc 2.39 NPTL 2.39
startTime long: millis
305151844135

VirtualizationInformation

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Operating System

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:

  event.commit();
 }

TRACE_REQUEST_FUNC(OSInformation) {
  ResourceMark rm;
  char* os_name = NEW_RESOURCE_ARRAY(char, 2048);
  JfrOSInterface::os_version(&os_name);
  EventOSInformation event;
  event.set_osVersion(os_name);
  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();
}

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
name string Name

Examples 3
name string
Hyper-V virtualization
startTime long: millis
471657403942
name string
Hyper-V virtualization
startTime long: millis
483076719001
name string
Hyper-V virtualization
startTime long: millis
352191106254

InitialEnvironmentVariable

profiling default startTime end of every chunk 11 17 21 25 26 27 graal vm

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/jfrOSInterface.cpp:

  } else if (vrt == PowerFullPartitionMode) {
    return "Power full partition";
  }

  return "No virtualization detected";
}

int JfrOSInterface::generate_initial_environment_variable_events() {
  if (os::get_environ() == NULL) {
    return OS_ERR;
  }

  if (EventInitialEnvironmentVariable::is_enabled()) {
    // One time stamp for all events, so they can be grouped together
    JfrTicks time_stamp = JfrTicks::now();
    for (char** p = os::get_environ(); *p != NULL; p++) {
      char* variable = *p;
      char* equal_sign = strchr(variable, '=');
      if (equal_sign != NULL) {
        // Extract key/value
        ResourceMark rm;
        ptrdiff_t key_length = equal_sign - variable;
        char* key = NEW_RESOURCE_ARRAY(char, key_length + 1);
        char* value = equal_sign + 1;
        strncpy(key, variable, key_length);
        key[key_length] = '\0';
        EventInitialEnvironmentVariable event(UNTIMED);
        event.set_starttime(time_stamp);
        event.set_endtime(time_stamp);
        event.set_key(key);
        event.set_value(value);
        event.commit();
      }
    }
  }
  return OS_OK;
}

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
key string Key
value string Value

Examples 3
key string
SELENIUM_JAR_PATH
startTime long: millis
371346718444
value string
/usr/share/java/selenium-server.jar
key string
USER
startTime long: millis
378900894646
value string
runner
key string
JAVA_HOME_8_X64
startTime long: millis
278169438967
value string
/usr/lib/jvm/temurin-8-jdk-amd64

SystemProcess

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Operating System

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:

    while (processes != NULL) {
      SystemProcess* tmp = processes;
      const char* info = processes->command_line();
      if (info == NULL) {
         info = processes->path();
      }
      if (info == NULL) {
         info = processes->name();
      }
      if (info == NULL) {
         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;
    }
  }
}

Configuration enabled period
profiling true endChunk
default true endChunk

Field Type Description
pid string Process Identifier
commandLine string Command Line

CPUInformation

profiling default startTime duration end of every chunk 11 17 21 25 26 27

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/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

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
cpu string Type
description string Description
sockets uint Sockets
cores uint Cores
hwThreads uint Hardware Threads

Examples 3
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
426580467435
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: 0x03100800, ecx: 0xfeda3203, edx: 0x178bfbff Ext. features: eax: 0x00a00f1
hwThreads uint
4
sockets uint
1
startTime long: millis
422012642747
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
286462746385

CPUTimeStampCounter

profiling default startTime duration end of every chunk 11 17 21 25 26 27

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/jfrPeriodic.cpp:

    event.commit();
  }
}

TRACE_REQUEST_FUNC(ThreadCPULoad) {
  JfrThreadCPULoadEvent::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 = NULL;
  int num_of_processes = 0;

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
fastTimeEnabled boolean Fast Time
fastTimeAutoEnabled boolean Trusted Platform
osFrequency long: hertz OS Frequency
fastTimeFrequency long: hertz Fast Time Frequency

Examples 3
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
451341064357
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
474336856541
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
308197057078

CPULoad

profiling default startTime duration every chunk 11 17 21 25 26 27

Category: Operating System / Processor

OS CPU Load

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();
}

Configuration enabled period
profiling true 1000 ms
default true 1000 ms

Field Type Description
jvmUser float: percentage JVM User
jvmSystem float: percentage JVM System
machineTotal float: percentage Machine Total

Examples 3
jvmSystem float: percentage
0.0074626864
jvmUser float: percentage
0.87810946
machineTotal float: percentage
0.8880597
startTime long: millis
465840782711
jvmSystem float: percentage
0.058411215
jvmUser float: percentage
0.78504676
machineTotal float: percentage
0.84345794
startTime long: millis
354514988597
jvmSystem float: percentage
0.05
jvmUser float: percentage
0.4
machineTotal float: percentage
0.4575
startTime long: millis
481416347930

ThreadCPULoad

profiling default startTime duration eventThread every chunk 11 17 21 25 26 27

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.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

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 != NULL, "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();
    }
  }
}

Configuration enabled period
profiling true 10 s
default true 10 s

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
startTime long: millis
305317440914
system float: percentage
9.931856E-4
user float: percentage
0.0
startTime long: millis
432087373753
system float: percentage
1.0161644E-5
user float: percentage
0.0
startTime long: millis
380959998366
system float: percentage
6.615808E-6
user float: percentage
1.0136699E-4

ThreadContextSwitchRate

profiling default startTime duration every chunk 11 17 21 25 26 27

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/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() != NULL) {                                \
      if (flag->is_ ## flagType()) {                              \
        if (flag->is_unlocked()) {                                \

Configuration enabled period
profiling true 10 s
default true 10 s

Field Type Description
switchRate float: hertz Switch Rate Number of context switches per second

Examples 3
startTime long: millis
472108918423
switchRate float: hertz
3372.7505
startTime long: millis
435409561620
switchRate float: hertz
2481.395
startTime long: millis
321605905740
switchRate float: hertz
5925.646

NetworkUtilization

profiling default startTime every chunk 11 17 21 25 26 27

Category: Operating System / Network

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 != NULL; 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;
    }

Configuration enabled period
profiling true 5 s
default true 5 s

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
networkInterface NetworkInterfaceName
eth0
readRate long: bits-per-second
7256
startTime long: millis
488745197288
writeRate long: bits-per-second
45456
networkInterface NetworkInterfaceName
eth0
readRate long: bits-per-second
6048
startTime long: millis
363560785506
writeRate long: bits-per-second
12760
networkInterface NetworkInterfaceName
eth0
readRate long: bits-per-second
7064
startTime long: millis
481152682896
writeRate long: bits-per-second
44504

PhysicalMemory

profiling default startTime duration every chunk 11 17 21 25 26 27 graal vm

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) {
  u8 totalPhysicalMemory = os::physical_memory();
  EventPhysicalMemory event;
  event.set_totalSize(totalPhysicalMemory);
  event.set_usedSize(totalPhysicalMemory - os::available_memory());
  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());

Configuration enabled period
profiling true everyChunk
default true everyChunk

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
startTime long: millis
406997012595
totalSize ulong: bytes
16772579328
usedSize ulong: bytes
5946810368
startTime long: millis
334764281769
totalSize ulong: bytes
16772579328
usedSize ulong: bytes
3963600896
startTime long: millis
389978898590
totalSize ulong: bytes
16772575232
usedSize ulong: bytes
3960381440

ContainerMemoryUsage

profiling default startTime duration stackTrace 17 21 25 26 27

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/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 AbstractJDKEvent {
    @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")

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

    private static void initializeContainerEvents() {
        if (JVM.getJVM().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
        SecuritySupport.registerEvent(ContainerConfigurationEvent.class);
        SecuritySupport.registerEvent(ContainerCPUUsageEvent.class);
        SecuritySupport.registerEvent(ContainerCPUThrottlingEvent.class);
        SecuritySupport.registerEvent(ContainerMemoryUsageEvent.class);
        SecuritySupport.registerEvent(ContainerIOUsageEvent.class);

        RequestEngine.addTrustedJDKHook(ContainerConfigurationEvent.class, emitContainerConfiguration);
        RequestEngine.addTrustedJDKHook(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        RequestEngine.addTrustedJDKHook(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        RequestEngine.addTrustedJDKHook(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        RequestEngine.addTrustedJDKHook(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void emitExceptionStatistics() {
        ExceptionStatisticsEvent t = new ExceptionStatisticsEvent();
        t.throwables = ThrowableTracer.numThrowables();
        t.commit();
    }

    private static void emitContainerConfiguration() {
        if (containerMetrics != null) {

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/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.commit();
        }
    }

    private static void emitContainerIOUsage() {
        if (containerMetrics != null) {
            ContainerIOUsageEvent event = new ContainerIOUsageEvent();

Configuration enabled period
profiling true 30 s
default true 30 s

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

ContainerConfiguration

profiling default startTime duration stackTrace 17 21 25 26 27

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/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 AbstractJDKEvent {
    @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")

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

    private static void initializeContainerEvents() {
        if (JVM.getJVM().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
        SecuritySupport.registerEvent(ContainerConfigurationEvent.class);
        SecuritySupport.registerEvent(ContainerCPUUsageEvent.class);
        SecuritySupport.registerEvent(ContainerCPUThrottlingEvent.class);
        SecuritySupport.registerEvent(ContainerMemoryUsageEvent.class);
        SecuritySupport.registerEvent(ContainerIOUsageEvent.class);

        RequestEngine.addTrustedJDKHook(ContainerConfigurationEvent.class, emitContainerConfiguration);
        RequestEngine.addTrustedJDKHook(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        RequestEngine.addTrustedJDKHook(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        RequestEngine.addTrustedJDKHook(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        RequestEngine.addTrustedJDKHook(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void emitExceptionStatistics() {
        ExceptionStatisticsEvent t = new ExceptionStatisticsEvent();
        t.throwables = ThrowableTracer.numThrowables();
        t.commit();
    }

    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.getJVM().hostTotalMemory();
            t.commit();
        }

Configuration enabled period
profiling true beginChunk
default true beginChunk

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

ContainerCPUUsage

profiling default startTime duration stackTrace 17 21 25 26 27

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/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 AbstractJDKEvent {
  @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")

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

    private static void initializeContainerEvents() {
        if (JVM.getJVM().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
        SecuritySupport.registerEvent(ContainerConfigurationEvent.class);
        SecuritySupport.registerEvent(ContainerCPUUsageEvent.class);
        SecuritySupport.registerEvent(ContainerCPUThrottlingEvent.class);
        SecuritySupport.registerEvent(ContainerMemoryUsageEvent.class);
        SecuritySupport.registerEvent(ContainerIOUsageEvent.class);

        RequestEngine.addTrustedJDKHook(ContainerConfigurationEvent.class, emitContainerConfiguration);
        RequestEngine.addTrustedJDKHook(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        RequestEngine.addTrustedJDKHook(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        RequestEngine.addTrustedJDKHook(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        RequestEngine.addTrustedJDKHook(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void emitExceptionStatistics() {
        ExceptionStatisticsEvent t = new ExceptionStatisticsEvent();
        t.throwables = ThrowableTracer.numThrowables();
        t.commit();
    }

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

            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.getJVM().hostTotalMemory();
            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();

Configuration enabled period
profiling true 30 s
default true 30 s

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

ProcessStart

profiling default startTime duration stackTrace 15 17 21 25 26 27

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

Category: Operating System

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/jdk.jfr/share/classes/jdk/jfr/events/ProcessStartEvent.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;

@Category({"Operating System"})
@Label("Process Start")
@Name("jdk.ProcessStart")
@Description("Operating system process started")
@MirrorEvent(className = "jdk.internal.event.ProcessStartEvent")
public final class ProcessStartEvent extends AbstractJDKEvent {
    @Label("Process Id")
    public long pid;

    @Label("Directory")
    public String directory;

    @Label("Command")
    public String command;
}

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

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

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/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();
            }
            return process;
        } catch (IOException | IllegalArgumentException e) {
            String exceptionInfo = ": " + e.getMessage();
            Throwable cause = e;
            if ((e instanceof IOException) && security != null) {

Configuration enabled stackTrace
profiling true true
default true true

Field Type Description
pid long Process Id
directory string Directory
command string Command

Examples 3
command string
rm -rf /home/runner/work/jfrevents/jfrevents/harness-003928-7951762178349451551/apache-spark/gauss-mix/blockmgr-cbc400f7-2a66-482f-8d2a-819ca70a304f
directory string
null
pid long
5160
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
232
lineNumber int
1154
method Method
descriptor string
([Ljava/lang/ProcessBuilder$Redirect;)Ljava/lang/Process;
hidden boolean
false
modifiers int
2
name string
start
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/ProcessBuilder
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
java/lang
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
455060427419
command string
rm -rf /home/runner/work/jfrevents/jfrevents/harness-003916-17833306698725904421/apache-spark/gauss-mix/spark-3378aa9e-5662-4829-8f01-7a423fb3bcbc/userFiles-933c2f2b-1cca-4878-8bfc-63048f619f7d
directory string
null
pid long
4550
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
232
lineNumber int
1154
method Method
descriptor string
([Ljava/lang/ProcessBuilder$Redirect;)Ljava/lang/Process;
hidden boolean
false
modifiers int
2
name string
start
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/ProcessBuilder
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
21.0.9
name string
java/lang
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
463221796162
command string
rm -rf /home/runner/work/jfrevents/jfrevents/harness-003927-11018005009666797249/apache-spark/gauss-mix/spark-826eb52c-1804-4522-a16e-ab52190bba4b/userFiles-168bbb92-35c2-4b62-97c4-798c0c35f4e3
directory string
null
pid long
4532
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
232
lineNumber int
1154
method Method
descriptor string
([Ljava/lang/ProcessBuilder$Redirect;)Ljava/lang/Process;
hidden boolean
false
modifiers int
2
name string
start
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/ProcessBuilder
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
21.0.9
name string
java/lang
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
338042901137

ContainerIOUsage

profiling default startTime duration stackTrace 17 21 25 26 27

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/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 AbstractJDKEvent {

  @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;
}

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

        if (JVM.getJVM().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
        SecuritySupport.registerEvent(ContainerConfigurationEvent.class);
        SecuritySupport.registerEvent(ContainerCPUUsageEvent.class);
        SecuritySupport.registerEvent(ContainerCPUThrottlingEvent.class);
        SecuritySupport.registerEvent(ContainerMemoryUsageEvent.class);
        SecuritySupport.registerEvent(ContainerIOUsageEvent.class);

        RequestEngine.addTrustedJDKHook(ContainerConfigurationEvent.class, emitContainerConfiguration);
        RequestEngine.addTrustedJDKHook(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        RequestEngine.addTrustedJDKHook(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        RequestEngine.addTrustedJDKHook(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        RequestEngine.addTrustedJDKHook(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void emitExceptionStatistics() {
        ExceptionStatisticsEvent t = new ExceptionStatisticsEvent();
        t.throwables = ThrowableTracer.numThrowables();
        t.commit();
    }

    private static void emitContainerConfiguration() {
        if (containerMetrics != null) {
            ContainerConfigurationEvent t = new ContainerConfigurationEvent();

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

    private static void emitContainerMemoryUsage() {
        if (containerMetrics != null) {
            ContainerMemoryUsageEvent event = new ContainerMemoryUsageEvent();

            event.memoryFailCount = containerMetrics.getMemoryFailCount();
            event.memoryUsage = containerMetrics.getMemoryUsage();
            event.swapMemoryUsage = containerMetrics.getMemoryAndSwapUsage();
            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();

Configuration enabled period
profiling true 30 s
default true 30 s

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

ContainerCPUThrottling

profiling default startTime duration stackTrace 17 21 25 26 27

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/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 AbstractJDKEvent {
  @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

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

    private static void initializeContainerEvents() {
        if (JVM.getJVM().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
        SecuritySupport.registerEvent(ContainerConfigurationEvent.class);
        SecuritySupport.registerEvent(ContainerCPUUsageEvent.class);
        SecuritySupport.registerEvent(ContainerCPUThrottlingEvent.class);
        SecuritySupport.registerEvent(ContainerMemoryUsageEvent.class);
        SecuritySupport.registerEvent(ContainerIOUsageEvent.class);

        RequestEngine.addTrustedJDKHook(ContainerConfigurationEvent.class, emitContainerConfiguration);
        RequestEngine.addTrustedJDKHook(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        RequestEngine.addTrustedJDKHook(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        RequestEngine.addTrustedJDKHook(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        RequestEngine.addTrustedJDKHook(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void emitExceptionStatistics() {
        ExceptionStatisticsEvent t = new ExceptionStatisticsEvent();
        t.throwables = ThrowableTracer.numThrowables();
        t.commit();
    }

    private static void emitContainerConfiguration() {

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/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();
        }
    }

    @SuppressWarnings("deprecation")
    public static byte[] retransformCallback(Class<?> klass, byte[] oldBytes) throws Throwable {
        if (java.lang.Throwable.class == klass) {

Configuration enabled period
profiling true 30 s
default true 30 s

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

Truffle Compiler

org.graalvm.compiler.truffle.CompilerStatistics

startTime duration every 1s graal vm only

Category: Truffle Compiler

Truffe Compiler Statistics

Field Type Description
compiledMethods ulong Compiled Methods Compiled Methods
bailouts ulong Bailouts Bailouts
invalidations ulong Invalidated Compilations Invalidated Compilations
compiledCodeSize ulong: bytes Compilation Resulting Size Compilation Resulting Size
totalTime long: millis Total Time Total Time
peakTime long: millis Peak Time Peak Time

org.graalvm.compiler.truffle.CompilationFailure

startTime duration graal vm only

Category: Truffle Compiler

Truffe Compilation Failures

Field Type Description
source string Source Compiled Source
language string 17 21 until JDK 22 Language Guest Language
rootFunction string Root Function Root Function
permanentFailure boolean Permanent Failure Permanent Failure
failureReason string Failure Reason Failure Reason

org.graalvm.compiler.truffle.Deoptimization

startTime duration graal vm only

Category: Truffle Compiler

Truffle Call Target Deoptimization

Field Type Description
source string Source Compiled Source
language string 17 21 until JDK 22 Language Guest Language
rootFunction string Root Function Root Function

org.graalvm.compiler.truffle.AssumptionInvalidation

startTime duration stackTrace graal vm only

Category: Truffle Compiler

Truffle Assumption Invalidation

Field Type Description
source string Source Compiled Source
language string 17 21 until JDK 22 Language Guest Language
rootFunction string Root Function Root Function
reason string Reason Invalidation Reason

org.graalvm.compiler.truffle.Compilation

startTime duration graal vm only

Category: Truffle Compiler

Truffe Compilation

Field Type Description
source string Source Compiled Source
language string 17 21 until JDK 22 Language Guest Language
rootFunction string Root Function Root Function
success boolean Succeeded Compilation Status
compiledCodeSize uint: bytes Compiled Code Size Compiled Code Size
compiledCodeAddress long Compiled Code Address Compiled Code Address
inlinedCalls uint Inlined Calls Inlined Calls
dispatchedCalls uint Dispatched Calls Dispatched Calls
graalNodeCount uint Graal Nodes Graal Node Count
peNodeCount uint Truffle Nodes Truffle Node Count
peTime ulong Partial Evaluation Time Partial Evaluation Time in Milliseconds

Types

Bytecode

14+

Bytecode Instruction

Field Type Description
bytecode string Instruction

Examples 3
instanceof
ifne
if_icmpge

CalleeMethod

Field Type Description
type string Class
name string Method Name
descriptor string Method Descriptor

Examples 3
descriptor string
()V
name string
<init>
type string
java/lang/Object
descriptor string
()V
name string
<init>
type string
scala/collection/mutable/AbstractSeq
descriptor string
(Z)Lscala/runtime/BooleanRef;
name string
create
type string
scala/runtime/BooleanRef

ChunkHeader

14+

Chunk Header

Field Type Description
payload array byte Payload

Class

Java Class

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

Field Type Description
type Class Type
name Symbol Name

CodeBlobType

Code Blob Type

Field Type Description
type string Type

Examples 3
CodeHeap 'profiled nmethods'
CodeHeap 'non-nmethods'
CodeHeap 'non-nmethods'

CompilerPhaseType

Compiler Phase Type

Field Type Description
phase string Phase

CompilerType

14+

Compiler Type

Field Type Description
compiler string Compiler

Examples 3

CopyFailed

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+

Deoptimization Action

Field Type Description
action string Action

Examples 3
reinterpret
maybe_recompile
maybe_recompile

DeoptimizationReason

14+

Deoptimization Reason

Field Type Description
reason string Reason

Examples 3
profile_predicate
unstable_if
class_check

FlagValueOrigin

Flag Value Origin

Field Type Description
origin string Origin

Examples 3
Default
Default
Default

FrameType

Frame type

Field Type Description
description string Description

Examples 3
JIT compiled
JIT compiled
Inlined

G1EvacuationStatistics

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

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 2
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
978
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
allocated ulong: bytes
3251312
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1096
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
2
undoWaste ulong: bytes
0
used ulong: bytes
2147904
wasted ulong: bytes
96

G1HeapRegionType

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

G1 Heap Region Type

Field Type Description
type string Type

Examples 1
Free

G1YCType

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

G1 YC Type

Field Type Description
type string Type

Examples 1
Concurrent Start

GCCause

GC Cause

Field Type Description
cause string Cause

Examples 3
Allocation Failure
Heap Inspection Initiated GC
Heap Inspection Initiated GC

GCName

GC Name

Field Type Description
name string Name

Examples 3
G1Full
G1New
G1Old

GCThresholdUpdater

GC Threshold Updater

Field Type Description
updater string Updater

Examples 3
compute_new_size
compute_new_size
compute_new_size

GCWhen

GC When

Field Type Description
when string When

Examples 3
Before GC
After GC
After GC

InflateCause

Inflation Cause

Field Type Description
cause string Cause

MetadataType

Metadata Type

Field Type Description
type string Type

Examples 3
Metadata
Class
Metadata

MetaspaceObjectType

Metaspace Object Type

Field Type Description
type string Type

MetaspaceSizes

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
committed ulong: bytes
659030016
reserved ulong: bytes
1677721600
used ulong: bytes
655248792
committed ulong: bytes
570949632
reserved ulong: bytes
603979776
used ulong: bytes
569028544
committed ulong: bytes
88080384
reserved ulong: bytes
1073741824
used ulong: bytes
86220248

Method

Java Method

Field Type Description
type Class Type
name Symbol Name
descriptor Symbol Descriptor
modifiers int Access Modifiers
hidden boolean Hidden

Module

Module

Field Type Description
name Symbol Name
version Symbol Version
location Symbol Location
classLoader ClassLoader Class Loader

NarrowOopMode

Narrow Oop Mode

Field Type Description
mode string Mode

Examples 3
Zero based
Zero based
Zero based

NetworkInterfaceName

Network Interface

Field Type Description
networkInterface string Network Interface Network Interface Name

Examples 3
eth0
eth0
eth0

ObjectSpace

Appearing in: ParallelGC

Missing in: G1GC, SerialGC, ShenandoahGC, ZGC

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
end ulong: address
34230239232
size ulong: bytes
1268252672
start ulong: address
32961986560
used ulong: bytes
0
end ulong: address
31729909760
size ulong: bytes
1564475392
start ulong: address
30165434368
used ulong: bytes
223452200
end ulong: address
34270085120
size ulong: bytes
18350080
start ulong: address
34251735040
used ulong: bytes
0

OldObject

Appearing in: G1GC, ParallelGC, SerialGC, ZGC

Missing in: ShenandoahGC

Old Object

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
address ulong: address
30399065944
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
8
name string
java/util/concurrent/LinkedBlockingQueue$Node
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
java/util/concurrent
address ulong: address
30379343872
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
address ulong: address
31702930736
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
java/net
hidden boolean
false
modifiers int
1041
name string
[Lscala/reflect/internal/Names$TypeName;
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
21.0.9
name string
java/net
location string
null
name string
null
version string
null
name string
scala/reflect/internal

OldObjectArray

Old Object Array

Field Type Description
size int Array Size Size of array
index int Index Index in the array

OldObjectField

Old Object Field

Field Type Description
name string Field Name of field
modifiers short Field Modifiers Field modifiers

OldObjectGcRoot

Appearing in: G1GC, ParallelGC, SerialGC, ZGC

Missing in: ShenandoahGC

GC Root

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
null
null
null

OldObjectRootSystem

GC Root System

Field Type Description
system string System

OldObjectRootType

GC Root Type

Field Type Description
type string Type

Package

Package

Field Type Description
name Symbol Name
module Module Module
exported boolean Exported

Reference

Appearing in: G1GC, ParallelGC, SerialGC, ZGC

Missing in: ShenandoahGC

Reference

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
null
null
null

ReferenceType

Reference Type

Field Type Description
type string Type

Examples 3
Phantom reference
Weak reference
Weak reference

ShenandoahHeapRegionState

Appearing in: ShenandoahGC

Missing in: G1GC, ParallelGC, SerialGC, ZGC

Shenandoah Heap Region State

Field Type Description
state string State

Examples 2
Regular
Trash

StackFrame

Field Type Description
method Method Java Method
lineNumber int Line Number
bytecodeIndex int Bytecode Index
type FrameType Frame Type

Examples 3
bytecodeIndex int
30
lineNumber int
259
method Method
descriptor string
()V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Throwable
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
21.0.9
name string
java/lang
type FrameType
Inlined
bytecodeIndex int
304
lineNumber int
1436
method Method
descriptor string
(Ljava/lang/Class;I)V
hidden boolean
false
modifiers int
2
name string
filterCheck
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/ObjectInputStream
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
21.0.9
name string
java/io
type FrameType
JIT compiled
bytecodeIndex int
2
lineNumber int
2577
method Method
descriptor string
(Ljava/lang/Thread;Ljdk/internal/vm/ThreadContainer;)V
hidden boolean
false
modifiers int
1
name string
start
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/System$2
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
21.0.9
name string
java/lang
type FrameType
Inlined

StackTrace

Stacktrace

Field Type Description
truncated boolean Truncated
frames array StackFrame struct Stack Frames

Symbol

Symbol

Field Type Description
string string String

Examples 3
file:///home/runner/work/jfrevents/jfrevents/harness-003927-11018005009666797249/twitter-finagle/lib/finagle-netty4_2.13-22.12.0.jar
file:///home/runner/work/jfrevents/jfrevents/harness-003928-7951762178349451551/apache-spark/lib/netty-buffer-4.1.99.Final.jar
file:///home/runner/work/jfrevents/jfrevents/harness-003916-17833306698725904421/apache-spark/lib/spark-core_2.13-3.5.0.jar

Thread

Thread

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

Field Type Description
parent ThreadGroup Parent
name string Name

Examples 3
null
name string
system
parent ThreadGroup
null
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null

ThreadState

Java Thread State

Field Type Description
name string Name

Examples 3
STATE_RUNNABLE
STATE_RUNNABLE
STATE_RUNNABLE

VMOperationType

VM Operation Type

Field Type Description
type string Type

Examples 3
JFRSafepointWrite
ParallelGCFailedAllocation
ICBufferFull

VirtualSpace

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
committedEnd ulong: address
33038008320
committedSize ulong: bytes
2872573952
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4194304000
start ulong: address
30165434368
committedEnd ulong: address
31729909760
committedSize ulong: bytes
1564475392
reservedEnd ulong: address
32961986560
reservedSize ulong: bytes
2796552192
start ulong: address
30165434368
committedEnd ulong: address
31151095808
committedSize ulong: bytes
985661440
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4194304000
start ulong: address
30165434368

ZPageTypeType

15+

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Z Page Type

Field Type Description
type string Type

Examples 2
Medium
Small

ZStatisticsCounterType

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Z Statistics Counter

Field Type Description
counter string Counter

Examples 1
Page Cache Hit L1

ZStatisticsSamplerType

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Z Statistics Sampler

Field Type Description
sampler string Sampler

Examples 1
Page Cache Flush

XML Content Types

address

Annotation: jdk.jfr.MemoryAddress

Examples 3
30471618560
30321610296
30165434368

bits-per-second

Annotation: jdk.jfr.DataAmount(BITS), jdk.jfr.Frequency

Examples 3
6048
12760
7064

bytes

Annotation: jdk.jfr.DataAmount(BYTES)

Examples 3
0
80
819616

bytes-per-second

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Annotation: jdk.jfr.DataAmount(BYTES), jdk.jfr.Frequency

Examples 2
0.0
3.461737356160282E8

certificateId

Annotation: jdk.jfr.events.CertificateId

Examples 3
3045411335
3045411335
3045411335

epochmillis

Annotation: jdk.jfr.Timestamp(MILLISECONDS_SINCE_EPOCH)

Examples 3
1767487166908
1767487167450
-9223372036854775808

hertz

Annotation: jdk.jfr.Frequency

Examples 3
1000000000
1000000000
5925.646

microseconds

17+

Annotation: jdk.jfr.Timespan(MICROSECONDS)

millis

Annotation: jdk.jfr.Timespan(MILLISECONDS)

Examples 3
291247493123
278765123745
275178143386

nanos

Annotation: jdk.jfr.Timespan(NANOSECONDS)

Examples 3
-9223372036854775808
9999999
10000000

percentage

Annotation: jdk.jfr.Percentage

Examples 3
0.058411215
0.78504676
0.84345794

tickspan

Annotation: jdk.jfr.Timespan(TICKS)

Examples 3
153515175
6934342
24322427049

tickstamp

Annotation: jdk.jfr.Timestamp(TICKS)

XML Types

Class

Parameter Type const Klass*
Field Type const Klass*
Java Type java.lang.Class
Examples 3
null
null
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[F
package Package
null

ClassLoader

Parameter Type const ClassLoaderData*
Field Type const ClassLoaderData*
Examples 3
name string
bootstrap
type Class
null
name string
bootstrap
type Class
null
name string
bootstrap
type Class
null

Method

Parameter Type const Method*
Field Type const Method*
Examples 3
descriptor string
(Ljava/lang/Class;I)V
hidden boolean
false
modifiers int
2
name string
filterCheck
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/ObjectInputStream
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
21.0.9
name string
java/io
descriptor string
(Ljava/lang/Thread;Ljdk/internal/vm/ThreadContainer;)V
hidden boolean
false
modifiers int
1
name string
start
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/System$2
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
21.0.9
name string
java/lang
descriptor string
()V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Throwable
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
21.0.9
name string
java/lang

Module

Parameter Type const ModuleEntry*
Field Type const ModuleEntry*
Examples 3
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9

Package

Parameter Type const PackageEntry*
Field Type const PackageEntry*
Examples 3
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
java/io
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.9
name string
java/lang
null

StackTrace

15+

Parameter Type u8
Field Type u8
Java Type jdk.types.StackTrace
Examples 3
frames StackFrame
bytecodeIndex int
2
lineNumber int
2577
method Method
descriptor string
(Ljava/lang/Thread;Ljdk/internal/vm/ThreadContainer;)V
hidden boolean
false
modifiers int
1
name string
start
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/System$2
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
21.0.9
name string
java/lang
type FrameType
Inlined
truncated boolean
false
frames StackFrame
bytecodeIndex int
30
lineNumber int
259
method Method
descriptor string
()V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Throwable
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
21.0.9
name string
java/lang
type FrameType
Inlined
truncated boolean
true
frames StackFrame
bytecodeIndex int
304
lineNumber int
1436
method Method
descriptor string
(Ljava/lang/Class;I)V
hidden boolean
false
modifiers int
2
name string
filterCheck
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/ObjectInputStream
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
21.0.9
name string
java/io
type FrameType
JIT compiled
truncated boolean
true

Thread

Parameter Type u8
Field Type u8
Java Type java.lang.Thread
Examples 3
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-storage-async-thread-pool-63
javaThreadId long
1299
osName string
block-manager-storage-async-thread-pool-63
osThreadId long
3901
virtual boolean
false
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
dispatcher-BlockManagerEndpoint1
javaThreadId long
1150
osName string
dispatcher-BlockManagerEndpoint1
osThreadId long
3704
virtual boolean
false
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-ask-thread-pool-56
javaThreadId long
1334
osName string
block-manager-ask-thread-pool-56
osThreadId long
4595
virtual boolean
false

Ticks

unsigned

Appearing in: G1GC, ParallelGC, SerialGC, ZGC

Missing in: ShenandoahGC

Parameter Type const Ticks&
Field Type Ticks
Java Type long
Content Type tickstamp
Examples 3
343014264425
298975048632
458059993979

Tickspan

unsigned

Parameter Type const Tickspan&
Field Type Tickspan
Java Type long
Content Type tickspan

boolean

Parameter Type bool
Field Type bool
Java Type boolean
Examples 3
false
true
false

byte

Parameter Type s1
Field Type s1
Java Type byte

char

Parameter Type char
Field Type char
Java Type char

double

Parameter Type double
Field Type double
Java Type double
Examples 3
0.0
20.0
1.5625

float

Parameter Type float
Field Type float
Java Type float
Examples 3
2.062593
4.242546
4.254289

int

Parameter Type s4
Field Type s4
Java Type int
Examples 3
-1
1
2

long

Parameter Type s8
Field Type s8
Java Type long
Examples 3
3
74999
1506

short

Parameter Type s2
Field Type s2
Java Type short

string

Parameter Type const char*
Field Type const char*
Java Type java.lang.String
Examples 3
bootstrap
null
null

ubyte

unsigned

Parameter Type u1
Field Type u1
Java Type byte
Examples 3
32
7
15

uint

unsigned

Parameter Type unsigned
Field Type unsigned
Java Type int
Examples 3
988
984
146

ulong

unsigned

Parameter Type u8
Field Type u8
Java Type long
Examples 3

ushort

unsigned

Parameter Type u2
Field Type u2
Java Type short
Examples 3