Introduction

This page is a complete reference of Java Flight Recorder (JFR) events for OpenJDK 17 (jdk-17.0.21+8, permalink, 04-October-2026), and GraalVM 23.0.6 (jdk-17.0.13). JFR events are the foundation of JVM profiling and observability — they capture runtime data such as garbage collection pauses, CPU load, thread activity, class loading, compilations, and more. The events listed here are collected from the JFR event configuration and the OpenJDK source code. Visit the jfreventcollector repository for more information. This is also where you can contribute additional event descriptions, if you don't want to contribute them directly to the OpenJDK. The site generator lives on GitHub, too.

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

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

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

Flight Recorder

DumpReason

profiling default startTime 11 17 21 25 27 28

Category: Flight Recorder

Who requested the recording and why

Code Context

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

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

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) {

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

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

DataLoss

profiling default startTime graal vm only

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();

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

JVM_ENTRY_NO_ENV(void, jfr_include_thread(JNIEnv* env, jobject jvm, jobject t))
  JfrJavaSupport::include(t);
JVM_END

JVM_ENTRY_NO_ENV(jboolean, jfr_is_thread_excluded(JNIEnv* env, jobject jvm, jobject t))
  return JfrJavaSupport::is_excluded(t);
JVM_END

JVM_ENTRY_NO_ENV(jlong, jfr_chunk_start_nanos(JNIEnv* env, jobject jvm))
  return JfrRepository::current_chunk_start_nanos();
JVM_END

JVM_ENTRY_NO_ENV(jobject, jfr_get_handler(JNIEnv * env, jobject jvm, jobject clazz))
  return JfrJavaSupport::get_handler(clazz, thread);
JVM_END

JVM_ENTRY_NO_ENV(jboolean, jfr_set_handler(JNIEnv * env, jobject jvm, jobject clazz, jobject handler))
  return JfrJavaSupport::set_handler(clazz, handler, thread);
JVM_END

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

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

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

Flush

experimental startTime duration 14 17 21 25 27 28

Category: Flight Recorder

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

Missing in: graalvm_linux_native

Code Context

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

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

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

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

class StackTraceRepository : public StackObj {
 private:

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

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

Examples 3
Example event data values and properties
elements ulong
205
flushId ulong
20
size ulong: bytes
710862
startTime long: millis
20603727564
Example event data values and properties
elements ulong
2314
flushId ulong
222
size ulong: bytes
1124663
startTime long: millis
300972409006
Example event data values and properties
elements ulong
5249
flushId ulong
251
size ulong: bytes
1064858
startTime long: millis
589519617099

ActiveSetting

profiling default startTime duration stackTrace 11 17 21 25 27 28 graal vm

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 {

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

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

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

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

    private boolean inShutdown;

    public PlatformRecorder() throws Exception {
        repository = Repository.getRepository();
        Logger.log(JFR_SYSTEM, INFO, "Initialized disk repository");
        repository.ensureRepository();
        jvm.createNativeJFR();
        Logger.log(JFR_SYSTEM, INFO, "Created native");
        JDKEvents.initialize();
        Logger.log(JFR_SYSTEM, INFO, "Registered JDK events");
        JDKEvents.addInstrumentation();
        startDiskMonitor();
        activeRecordingEvent = EventType.getEventType(ActiveRecordingEvent.class);
        activeSettingEvent = EventType.getEventType(ActiveSettingEvent.class);
        shutdownHook = SecuritySupport.createThreadWitNoPermissions("JFR Shutdown Hook", new ShutdownHook(this));
        SecuritySupport.setUncaughtExceptionHandler(shutdownHook, new ShutdownHook.ExceptionHandler());
        SecuritySupport.registerShutdownHook(shutdownHook);

    }


    private static Timer createTimer() {
        try {
            List<Timer> result = new CopyOnWriteArrayList<>();
            Thread t = SecuritySupport.createThreadWitNoPermissions("Permissionless thread", ()-> {

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

    void writeActiveSettingEvent() {
        if (!type.isRegistered()) {
            return;
        }
        for (NamedControl nc : namedControls) {
            if (Utils.isSettingVisible(nc.control, type.hasEventHook())) {
                String value = nc.control.getLastValue();
                if (value == null) {
                    value = nc.control.getDefaultValue();
                }
                ActiveSettingEvent event = new ActiveSettingEvent();
                event.id = type.getId();
                event.name = nc.name;
                event.value = value;
                event.commit();
            }
        }
    }

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

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.TLSHandshakeEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,

        DirectBufferStatisticsEvent.class,
        InitialSecurityPropertyEvent.class,

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

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

Examples 3
Example event data values and properties
id long
80
name string
enabled
startTime long: millis
211893346
value string
true
Example event data values and properties
id long
15
name string
enabled
startTime long: millis
267893239570
value string
true
Example event data values and properties
id long
11
name string
stackTrace
startTime long: millis
540786499259
value string
true

ActiveRecording

profiling default startTime duration stackTrace 11 17 21 25 27 28 graal vm

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 {

    // To be accessed when holding recorder lock
    public static final ActiveRecordingEvent EVENT = new ActiveRecordingEvent();

    @Label("Id")
    public long id;

    @Label("Name")
    public String name;

    @Label("Destination")
    public String destination;

    @Label("Max Age")

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

    private RepositoryChunk currentChunk;
    private boolean inShutdown;

    public PlatformRecorder() throws Exception {
        repository = Repository.getRepository();
        Logger.log(JFR_SYSTEM, INFO, "Initialized disk repository");
        repository.ensureRepository();
        jvm.createNativeJFR();
        Logger.log(JFR_SYSTEM, INFO, "Created native");
        JDKEvents.initialize();
        Logger.log(JFR_SYSTEM, INFO, "Registered JDK events");
        JDKEvents.addInstrumentation();
        startDiskMonitor();
        activeRecordingEvent = EventType.getEventType(ActiveRecordingEvent.class);
        activeSettingEvent = EventType.getEventType(ActiveSettingEvent.class);
        shutdownHook = SecuritySupport.createThreadWitNoPermissions("JFR Shutdown Hook", new ShutdownHook(this));
        SecuritySupport.setUncaughtExceptionHandler(shutdownHook, new ShutdownHook.ExceptionHandler());
        SecuritySupport.registerShutdownHook(shutdownHook);

    }


    private static Timer createTimer() {
        try {
            List<Timer> result = new CopyOnWriteArrayList<>();

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

            if (chunk.isMissingFile()) {
                // With one chunkfile found missing, its likely more could've been removed too. Iterate through all recordings,
                // and check for missing files. This will emit more error logs that can be seen in subsequent recordings.
                for (PlatformRecording r : getRecordings()) {
                    r.removeNonExistantPaths();
                }
            }
        }
        FilePurger.purge();
    }

    private void writeMetaEvents() {
        if (activeRecordingEvent.isEnabled()) {
            ActiveRecordingEvent event = ActiveRecordingEvent.EVENT;
            for (PlatformRecording r : getRecordings()) {
                if (r.getState() == RecordingState.RUNNING && r.shouldWriteMetadataEvent()) {
                    event.id = r.getId();
                    event.name = r.getName();
                    WriteableUserPath p = r.getDestination();
                    event.destination = p == null ? null : p.getRealPathText();
                    Duration d = r.getDuration();
                    event.recordingDuration = d == null ? Long.MAX_VALUE : d.toMillis();
                    Duration age = r.getMaxAge();
                    event.maxAge = age == null ? Long.MAX_VALUE : age.toMillis();
                    Long size = r.getMaxSize();

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.TLSHandshakeEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,

        DirectBufferStatisticsEvent.class,
        InitialSecurityPropertyEvent.class,
    };

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

Event fields with their types and descriptions
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
Example event data values and properties
destination string
/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseG1GC_events.jfr
flushInterval long: millis
1000
id long
1
maxAge long: millis
9223372036854775807
maxSize long: bytes
0
name string
1
recordingDuration long: millis
27000
recordingStart long: epochmillis
1791076181468
startTime long: millis
11682218601
Example event data values and properties
destination string
/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_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
1791075906426
startTime long: millis
555679845320
Example event data values and properties
destination string
/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_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
1791075877311
startTime long: millis
289101258745

JVM

JVMInformation

profiling default startTime duration end of every chunk graal vm only

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:

#if INCLUDE_SHENANDOAHGC
#include "gc/shenandoah/shenandoahJfrSupport.hpp"
#endif
/**
 *  JfrPeriodic class
 *  Implementation of declarations in
 *  xsl generated traceRequestables.hpp
 */
#define TRACE_REQUEST_FUNC(id)    void JfrPeriodicEventSet::request##id(void)

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) {

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

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

Examples 3
Example event data values and properties
javaArguments string
/home/runner/work/jfrevents/jfrevents/.cache/jfr_sample_app.jar
jvmArguments string
--add-exports=java.base/jdk.internal.vm.annotation=ALL-UNNAMED -Djdk.attach.allowAttachSelf=true -XX:+UnlockDiagnosticVMOptions -XX:DiagnoseSyncOnValueBasedClasses=2 -XX:NativeMemoryTracking=summary -XX:StartFlightRecording=filename=/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseG1GC_even…
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1791076181271
jvmVersion string
OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS) for linux-amd64 JRE (25.0.4.1+1-LTS), built on 2026-08-14T07:36:00Z with gcc 14.2.0
pid long
4620
startTime long: millis
24562646276
Example event data values and properties
javaArguments string
/home/runner/work/jfrevents/jfrevents/.cache/renaissance.jar -t 5 -r 1 all
jvmArguments string
-XX:StartFlightRecording=filename=/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseG1GC.jfr,settings=/home/runner/work/jfrevents/jfrevents/.cache/jfc.jfc -XX:+UseG1GC
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1791075877084
jvmVersion string
OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS) for linux-amd64 JRE (25.0.4.1+1-LTS), built on 2026-08-14T07:36:00Z with gcc 14.2.0
pid long
2179
startTime long: millis
269313841248
Example event data values and properties
javaArguments string
/home/runner/work/jfrevents/jfrevents/.cache/renaissance.jar -t 5 -r 1 all
jvmArguments string
-XX:StartFlightRecording=filename=/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseParallelGC.jfr,settings=/home/runner/work/jfrevents/jfrevents/.cache/jfc.jfc -XX:+UseParallelGC
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1791075906084
jvmVersion string
OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS) for linux-amd64 JRE (25.0.4.1+1-LTS), built on 2026-08-14T07:36:00Z with gcc 14.2.0
pid long
2434
startTime long: millis
542876255467

InitialSystemProperty

profiling default startTime end of every chunk graal vm only

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_endtime(time_stamp);
      event.commit();
    }
    p = p->next();
  }
}

TRACE_REQUEST_FUNC(ThreadAllocationStatistics) {
  ResourceMark rm;

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

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

Examples 3
Example event data values and properties
key string
sun.java.command
startTime long: millis
11693262552
value string
/home/runner/work/jfrevents/jfrevents/.cache/jfr_sample_app.jar
Example event data values and properties
key string
java.home
startTime long: millis
542876297696
value string
/opt/hostedtoolcache/Java_SapMachine_jdk/25.0.4-1/x64
Example event data values and properties
key string
java.vm.specification.version
startTime long: millis
267898384981
value string
25

JVM: Class Loading

ClassLoad

startTime duration eventThread stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / Class Loading

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

Missing in: graalvm_linux_native

Code Context

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

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

        InstanceKlass* check = loader_data->dictionary()->find_class(name_hash, 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 = placeholders()->get_entry(name_hash, 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();
  unsigned int name_hash = dictionary->compute_hash(name);

  // Do lookup to see if class already exists and the protection domain
  // has the right access.

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/systemDictionary.hpp:

//

class BootstrapInfo;
class ClassFileStream;
class ClassLoadInfo;
class Dictionary;
template <MEMFLAGS F> class HashtableBucket;
class ResolutionErrorTable;
class SymbolPropertyTable;
class PackageEntry;
class ProtectionDomainCacheTable;
class ProtectionDomainCacheEntry;
class GCTimer;
class EventClassLoad;
class Symbol;
class TableStatistics;

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

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/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);

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

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

Examples 3
Example event data values and properties
definingClassLoader ClassLoader
null
initiatingClassLoader ClassLoader
null
loadedClass Class
classLoader ClassLoader
null
hidden boolean
true
modifiers int
16
name string
java.lang.invoke.LambdaForm$DMH/0x000000009aabe800
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang/invoke
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/Class;Ljava/lang/String;[BIILjava/security/ProtectionDomain;ZILjava/lang/Object;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
540508841806
Example event data values and properties
definingClassLoader ClassLoader
name string
bootstrap
type Class
null
initiatingClassLoader ClassLoader
name string
bootstrap
type Class
null
loadedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
java/lang/Thread$ThreadNumbering
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
12
lineNumber int
1068
method Method
descriptor string
()Ljava/lang/String;
hidden boolean
false
modifiers int
8
name string
genThreadName
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
25.0.4.1
name string
java/lang
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
224069022
Example event data values and properties
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
initiatingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
loadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
true
modifiers int
4112
name string
org.apache.spark.status.AppStatusListener$$Lambda/0x000000004f86c400
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/status
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/Class;Ljava/lang/String;[BIILjava/security/ProtectionDomain;ZILjava/lang/Object;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
271291778248

ClassDefine

startTime eventThread stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / Class Loading

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

Missing in: graalvm_linux_native

Code Context

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

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

      // during compilations.
      MutexLocker mu(THREAD, Compile_lock);
      update_dictionary(name_hash, 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");

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

Event fields with their types and descriptions
Field Type Description
definedClass Class Defined Class
definingClassLoader ClassLoader Defining Class Loader

Examples 3
Example event data values and properties
definedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
org/apache/spark/HeartbeatReceiver$$anonfun$receiveAndReply$1$$anon$1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/String;[BIILjava/security/ProtectionDomain;Ljava/lang/String;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass1
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
271289599797
Example event data values and properties
definedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
jdk/internal/loader/URLClassPath$JarLoader$1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
definingClassLoader ClassLoader
name string
bootstrap
type Class
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
50
lineNumber int
710
method Method
descriptor string
(Ljava/lang/String;Ljava/util/jar/JarEntry;)Ljdk/internal/loader/Resource;
hidden boolean
false
modifiers int
0
name string
createResource
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/URLClassPath$JarLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
227332450
Example event data values and properties
definedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/sparkproject/jetty/util/IO
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/sparkproject/jetty/util
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/String;[BIILjava/security/ProtectionDomain;Ljava/lang/String;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass1
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
577365634262

ClassRedefinition

profiling default startTime 15 17 21 25 27 28

Category: Java Virtual Machine / Class Loading

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

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

  if (the_class->oop_map_cache() != 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)

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

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

Examples 3
Example event data values and properties
classModificationCount int
1
redefinedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/ArrayList
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
redefinitionId ulong
1
startTime long: millis
1302830755
Example event data values and properties
classModificationCount int
1
redefinedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/ArrayList
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
redefinitionId ulong
1
startTime long: millis
1225114143
Example event data values and properties
classModificationCount int
1
redefinedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/ArrayList
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
redefinitionId ulong
1
startTime long: millis
861958356

RedefineClasses

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

Category: Java Virtual Machine / Class Loading

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

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


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

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

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

Examples 3
Example event data values and properties
classCount int
1
redefinitionId ulong
2
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/instrument/ClassDefinition;)V
hidden boolean
false
modifiers int
258
name string
redefineClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.4.1
name string
sun/instrument
type FrameType
Native
…
truncated boolean
false
startTime long: millis
866615814
Example event data values and properties
classCount int
1
redefinitionId ulong
2
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/instrument/ClassDefinition;)V
hidden boolean
false
modifiers int
258
name string
redefineClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.4.1
name string
sun/instrument
type FrameType
Native
…
truncated boolean
false
startTime long: millis
1308272809
Example event data values and properties
classCount int
1
redefinitionId ulong
2
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/instrument/ClassDefinition;)V
hidden boolean
false
modifiers int
258
name string
redefineClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.4.1
name string
sun/instrument
type FrameType
Native
…
truncated boolean
false
startTime long: millis
1230506523

RetransformClasses

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

Category: Java Virtual Machine / Class Loading

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

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

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

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

Examples 3
Example event data values and properties
classCount int
1
redefinitionId ulong
1
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/Class;)V
hidden boolean
false
modifiers int
258
name string
retransformClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.4.1
name string
sun/instrument
type FrameType
Native
…
truncated boolean
false
startTime long: millis
859172588
Example event data values and properties
classCount int
1
redefinitionId ulong
1
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/Class;)V
hidden boolean
false
modifiers int
258
name string
retransformClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.4.1
name string
sun/instrument
type FrameType
Native
…
truncated boolean
false
startTime long: millis
1298235067
Example event data values and properties
classCount int
1
redefinitionId ulong
1
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/Class;)V
hidden boolean
false
modifiers int
258
name string
retransformClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.4.1
name string
sun/instrument
type FrameType
Native
…
truncated boolean
false
startTime long: millis
1221615628

ClassUnload

startTime eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Class Loading

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

Missing in: graalvm_linux_native

Code Context

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

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

  if (Arguments::is_dumping_archive()) {
    SystemDictionaryShared::remove_dumptime_info(ik);
  }

  if (log_is_enabled(Info, class, unload)) {
    ResourceMark rm;
    log_info(class, unload)("unloading class %s " INTPTR_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_constant_pool.

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

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

Examples 3
Example event data values and properties
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
startTime long: millis
295176310185
unloadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
true
modifiers int
4112
name string
dotty.tools.dotc.ast.tpd$TreeOps$$$Lambda/0x000000004fff9400
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
dotty/tools/dotc/ast
Example event data values and properties
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
0
name string
jfr_sample/Main$2
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
startTime long: millis
3583824235
unloadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
0
name string
jfr_sample/Main$2
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
hidden boolean
false
modifiers int
1
name string
jfr_sample/Unloadable510418242558
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
0
name string
jfr_sample/Main$2
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
location string
null
name string
null
version string
null
name string
jfr_sample
Example event data values and properties
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
startTime long: millis
599274898476
unloadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
true
modifiers int
4112
name string
org.renaissance.scala.dotty.Dotty$CompilationResult$$Lambda/0x000000009b276800
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/renaissance/scala/dotty

JVM: Code Cache

CodeCacheFull

profiling default startTime eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Code Cache

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

Code Context

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

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

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

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

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

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

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

CodeCacheStatistics

profiling default startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Code Cache

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

Missing in: graalvm_linux_native

Code Context

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

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

TRACE_REQUEST_FUNC(CompilerConfiguration) {
  EventCompilerConfiguration event;
  event.set_threadCount(CICompilerCount);
  event.set_tieredCompilation(TieredCompilation);
  event.commit();
}

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

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

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

Examples 3
Example event data values and properties
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'profiled nmethods'
entryCount int
9361
fullCount int
0
methodCount int
9361
reservedTopAddress ulong: address
140489512714240
startAddress ulong: address
140489388982272
startTime long: millis
267898504411
unallocatedCapacity ulong: bytes
101239168
Example event data values and properties
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'profiled nmethods'
entryCount int
1876
fullCount int
0
methodCount int
1876
reservedTopAddress ulong: address
140340262600704
startAddress ulong: address
140340138868736
startTime long: millis
11693353920
unallocatedCapacity ulong: bytes
119992704
Example event data values and properties
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'non-profiled nmethods'
entryCount int
9920
fullCount int
0
methodCount int
9920
reservedTopAddress ulong: address
140417299382272
startAddress ulong: address
140417175650304
startTime long: millis
542258166060
unallocatedCapacity ulong: bytes
111648384

CodeCacheConfiguration

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

Category: Java Virtual Machine / Code Cache

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

Missing in: graalvm_linux_native

Code Context

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

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

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

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

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

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

Examples 3
Example event data values and properties
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
6291456
nonProfiledSize ulong: bytes
123731968
profiledSize ulong: bytes
123731968
reservedSize ulong: bytes
253755392
reservedTopAddress ulong: address
140340392624128
startAddress ulong: address
140340138868736
startTime long: millis
213740134
Example event data values and properties
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
6291456
nonProfiledSize ulong: bytes
123731968
profiledSize ulong: bytes
123731968
reservedSize ulong: bytes
253755392
reservedTopAddress ulong: address
140417299382272
startAddress ulong: address
140417045626880
startTime long: millis
560501454352
Example event data values and properties
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
6291456
nonProfiledSize ulong: bytes
123731968
profiledSize ulong: bytes
123731968
reservedSize ulong: bytes
253755392
reservedTopAddress ulong: address
140489642737664
startAddress ulong: address
140489388982272
startTime long: millis
289104491947

JVM: Code Sweeper

SweepCodeCache

profiling default startTime duration eventThread 11 17 until JDK 20

Category: Java Virtual Machine / Code Sweeper

Code Context

The event is likely defined and utilized 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/sweeper.cpp:

  sweep_code_cache();

  // We are done with sweeping the code cache once.
  _total_nof_code_cache_sweeps++;

  if (_force_sweep) {
    // Notify requester that forced sweep finished
    MutexLocker mu(CodeSweeper_lock, Mutex::_no_safepoint_check_flag);
    _force_sweep = false;
    CodeSweeper_lock->notify();
  }
}

static void post_sweep_event(EventSweepCodeCache* event,
                             const Ticks& start,
                             const Ticks& end,
                             s4 traversals,
                             int swept,
                             int flushed,
                             int zombified) {
  assert(event != NULL, "invariant");
  assert(event->should_commit(), "invariant");
  event->set_starttime(start);
  event->set_endtime(end);
  event->set_sweepId(traversals);

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

  // it only makes sense to re-enable compilation if we have actually freed memory.
  // Note that typically several kB are released for sweeping 16MB of the code
  // cache. As a result, 'freed_memory' > 0 to restart the compiler.
  if (!CompileBroker::should_compile_new_jobs() && (freed_memory > 0)) {
    CompileBroker::set_should_compile_new_jobs(CompileBroker::run_compilation);
    log.debug("restart compiler");
    log_sweep("restart_compiler");
    EventJITRestart event;
    event.set_freedMemory(freed_memory);
    event.set_codeCacheMaxCapacity(CodeCache::max_capacity());
    event.commit();
  }

  EventSweepCodeCache event(UNTIMED);
  if (event.should_commit()) {
    post_sweep_event(&event, sweep_start_counter, sweep_end_counter, (s4)_traversals, swept_count, flushed_count, zombified_count);
  }
}

 // This function updates the sweeper statistics that keep track of nmethods
 // state changes. If there is 'enough' state change, the sweeper is invoked
 // as soon as possible. Also, we are guaranteed to invoke the sweeper if
 // the code cache gets full.
void NMethodSweeper::report_state_change(nmethod* nm) {
  Atomic::add(&_bytes_changed, (size_t)nm->total_size());

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

Event fields with their types and descriptions
Field Type Description
sweepId int Sweep Identifier
sweptCount uint Methods Swept
flushedCount uint Methods Flushed
zombifiedCount uint Methods Zombified

CodeSweeperStatistics

profiling default startTime every chunk 11 17 until JDK 20

Category: Java Virtual Machine / Code Sweeper

Code Context

The event is likely defined and utilized 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_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();
}

TRACE_REQUEST_FUNC(CodeSweeperStatistics) {
  EventCodeSweeperStatistics event;
  event.set_sweepCount(NMethodSweeper::traversal_count());
  event.set_methodReclaimedCount(NMethodSweeper::total_nof_methods_reclaimed());
  event.set_totalSweepTime(NMethodSweeper::total_time_sweeping());
  event.set_peakFractionTime(NMethodSweeper::peak_sweep_fraction_time());
  event.set_peakSweepTime(NMethodSweeper::peak_sweep_time());
  event.commit();
}

TRACE_REQUEST_FUNC(CodeSweeperConfiguration) {
  EventCodeSweeperConfiguration event;
  event.set_sweeperEnabled(MethodFlushing);

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

Event fields with their types and descriptions
Field Type Description
sweepCount int Sweeps
methodReclaimedCount int Methods Reclaimed
totalSweepTime Tickspan Time Spent Sweeping
peakFractionTime Tickspan Peak Time Fraction Sweep
peakSweepTime Tickspan Peak Time Full Sweep

CodeSweeperConfiguration

profiling default startTime end of every chunk 11 17 until JDK 20

Category: Java Virtual Machine / Code Sweeper

Code Context

The event is likely defined and utilized 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(CodeSweeperStatistics) {
  EventCodeSweeperStatistics event;
  event.set_sweepCount(NMethodSweeper::traversal_count());
  event.set_methodReclaimedCount(NMethodSweeper::total_nof_methods_reclaimed());
  event.set_totalSweepTime(NMethodSweeper::total_time_sweeping());
  event.set_peakFractionTime(NMethodSweeper::peak_sweep_fraction_time());
  event.set_peakSweepTime(NMethodSweeper::peak_sweep_time());
  event.commit();
}

TRACE_REQUEST_FUNC(CodeSweeperConfiguration) {
  EventCodeSweeperConfiguration event;
  event.set_sweeperEnabled(MethodFlushing);
  event.set_flushingEnabled(UseCodeCacheFlushing);
  event.set_sweepThreshold(NMethodSweeper::sweep_threshold_bytes());
  event.commit();
}


TRACE_REQUEST_FUNC(ShenandoahHeapRegionInformation) {
#if INCLUDE_SHENANDOAHGC
  if (UseShenandoahGC) {
    VM_ShenandoahSendHeapRegionInfoEvents op;

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

Event fields with their types and descriptions
Field Type Description
sweeperEnabled boolean Code Sweeper Enabled
flushingEnabled boolean Code Cache Flushing Enabled
sweepThreshold ulong: bytes 17 until JDK 20 Sweep Threshold

JVM: Compiler

JITRestart

profiling default startTime eventThread 17 21 25 27 28

Category: Java Virtual Machine / Compiler

Restart of the JIT compilers after they were stopped

Code Context

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

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

  // Sweeper is the only case where memory is released, check here if it
  // is time to restart the compiler. Only checking if there is a certain
  // amount of free memory in the code cache might lead to re-enabling
  // compilation although no memory has been released. For example, there are
  // cases when compilation was disabled although there is 4MB (or more) free
  // memory in the code cache. The reason is code cache fragmentation. Therefore,
  // it only makes sense to re-enable compilation if we have actually freed memory.
  // Note that typically several kB are released for sweeping 16MB of the code
  // cache. As a result, 'freed_memory' > 0 to restart the compiler.
  if (!CompileBroker::should_compile_new_jobs() && (freed_memory > 0)) {
    CompileBroker::set_should_compile_new_jobs(CompileBroker::run_compilation);
    log.debug("restart compiler");
    log_sweep("restart_compiler");
    EventJITRestart event;
    event.set_freedMemory(freed_memory);
    event.set_codeCacheMaxCapacity(CodeCache::max_capacity());
    event.commit();
  }

  EventSweepCodeCache event(UNTIMED);
  if (event.should_commit()) {
    post_sweep_event(&event, sweep_start_counter, sweep_end_counter, (s4)_traversals, swept_count, flushed_count, zombified_count);
  }
}

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

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

Compilation

profiling default startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Compiler

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

Missing in: graalvm_linux_native

Results of method compilation attempts

Code Context

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

src/jdk.internal.vm.ci/share/classes/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/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);

src/jdk.internal.vm.ci/share/classes/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/hotspot/share/compiler/compilerEvent.cpp:

  if (register_jfr_serializer) {
    JfrSerializer::register_serializer(TYPE_COMPILERPHASETYPE, false, new CompilerPhaseTypeConstant());
  } else if (Jfr::is_recording()) {
    // serialize new phase.
    JfrCheckpointWriter writer;
    writer.write_type(TYPE_COMPILERPHASETYPE);
    writer.write_count(1);
    writer.write_key(index);
    writer.write(phase_name);
  }
  return index;
}

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);
  event.commit();
}

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

  } else if (AbortVMOnCompilationFailure) {
    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);
    }
  }
  // simulate crash during compilation
  assert(task->compile_id() != CICrashAt, "just as planned");
}

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->code() == NULL) ? 0 : task->code()->total_size(),
                                        task->num_inlined_bytecodes());
}

int DirectivesStack::_depth = 0;

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

  // Allocate a new set of JNI handles.
  push_jni_handle_block();
  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:

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

Event fields with their types and descriptions
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
Example event data values and properties
codeSize ulong: bytes
1616
compileId uint
93499
compileLevel ushort
3
compiler CompilerType
c1
inlinedBytes ulong: bytes
27
isOsr boolean
false
method Method
descriptor string
(Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
true
modifiers int
8
name string
newInvokeSpecial
type Class
classLoader ClassLoader
null
hidden boolean
true
modifiers int
16
name string
java.lang.invoke.LambdaForm$DMH/0x000000004f7d5800
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang/invoke
startTime long: millis
268132137907
succeded boolean
true
Example event data values and properties
codeSize ulong: bytes
232
compileId uint
92424
compileLevel ushort
1
compiler CompilerType
c1
inlinedBytes ulong: bytes
0
isOsr boolean
false
method Method
descriptor string
()Lcom/codahale/metrics/Counter;
hidden boolean
false
modifiers int
1
name string
METRIC_SHUFFLE_RECORDS_WRITTEN
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/executor/ExecutorSource
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/executor
startTime long: millis
540787520050
succeded boolean
true
Example event data values and properties
codeSize ulong: bytes
1168
compileId uint
1459
compileLevel ushort
3
compiler CompilerType
c1
inlinedBytes ulong: bytes
13
isOsr boolean
false
method Method
descriptor string
(Ljava/lang/Thread;)Ljava/lang/ThreadLocal$ThreadLocalMap;
hidden boolean
false
modifiers int
0
name string
getMap
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/ThreadLocal
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
startTime long: millis
238826824
succeded boolean
true

CompilerPhase

profiling default startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Compiler

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

Missing in: graalvm_linux_native

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

Code Context

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

src/jdk.internal.vm.ci/share/classes/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

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, const char *name, int level) {
  EventCompilerPhase event;
  if (event.should_commit()) {
    CompilerEvent::PhaseEvent::post(event, C->_latest_stage_start_counter, cpt, C->_compile_id, level);
  }
#ifndef PRODUCT
  if (should_print(level)) {
    _printer->print_method(name, level);
  }
#endif
  C->_latest_stage_start_counter.stamp();
}

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

void Compile::print_method(CompilerPhaseType cpt, Node* n, int level) {
  ResourceMark rm;
  stringStream ss;
  ss.print_raw(CompilerPhaseTypeHelper::to_string(cpt));
  if (n != nullptr) {
    ss.print(": %d %s ", n->_idx, NodeClassNames[n->Opcode()]);
  } else {
    ss.print_raw(": nullptr");
  }
  C->print_method(cpt, ss.as_string(), level);
}

void Compile::end_method(int level) {
  EventCompilerPhase event;
  if (event.should_commit()) {
    CompilerEvent::PhaseEvent::post(event, C->_latest_stage_start_counter, PHASE_END, C->_compile_id, level);
  }

#ifndef PRODUCT
  if (_method != nullptr && should_print(level)) {
    _printer->end_method();
  }
#endif
}

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);
  event.commit();
}

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

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

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

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

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

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

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

  class CompilationEvent : AllStatic {
   public:

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

  class PhaseEvent : AllStatic {
    friend class CompilerPhaseTypeConstant;
   public:

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

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

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

src/hotspot/share/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, jobject caller, jobject callee, jboolean succeeded, jstring jmessage, jint bci))
  EventCompilerInlining event;
  if (event.should_commit()) {
    Method* caller_method = JVMCIENV->asMethod(caller);
    Method* callee_method = JVMCIENV->asMethod(callee);
    JVMCIObject message = JVMCIENV->wrap(jmessage);

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

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

Examples 3
Example event data values and properties
compileId uint
93469
phase CompilerPhaseType
Before Iter GVN
phaseLevel ushort
3
startTime long: millis
267232933882
Example event data values and properties
compileId uint
92501
phase CompilerPhaseType
After Loop Optimizations
phaseLevel ushort
2
startTime long: millis
540787759395
Example event data values and properties
compileId uint
1356
phase CompilerPhaseType
After Iter GVN
phaseLevel ushort
3
startTime long: millis
212738557

CompilationFailure

profiling startTime eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Compiler

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

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

Code Context

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

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

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);
  event.commit();
}

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

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

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

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

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

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

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

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

  class PhaseEvent : AllStatic {
    friend class CompilerPhaseTypeConstant;
   public:

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

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

// ------------------------------------------------------------------
// 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) {

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

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

Examples 3
Example event data values and properties
compileId uint
2681
failureMessage string
Jvmti state change invalidated dependencies
startTime long: millis
874775606
Example event data values and properties
compileId uint
95639
failureMessage string
retry without subsuming loads
startTime long: millis
584303411513
Example event data values and properties
compileId uint
98357
failureMessage string
retry without subsuming loads
startTime long: millis
287925783397

CompilerInlining

startTime eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Compiler / Optimization

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

Missing in: graalvm_linux_native

Describes the result of a method inlining attempt

Code Context

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

src/jdk.internal.vm.ci/share/classes/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
         */

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 != nullptr, "would crash in CompilerEvent::InlineEvent::post");
    if (Verbose) {
      const InlineTree *top = this;
      while (top->caller_tree() != nullptr) { 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) {
  assert(callee_method != nullptr, "caller checks for optimized virtual!");
  assert(!should_delay, "should be initialized to false");
#ifdef ASSERT

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.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);
  event.commit();
}

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

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

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

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

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

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

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/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, jobject caller, jobject callee, jboolean succeeded, jstring jmessage, jint bci))
  EventCompilerInlining event;
  if (event.should_commit()) {
    Method* caller_method = JVMCIENV->asMethod(caller);
    Method* callee_method = JVMCIENV->asMethod(callee);
    JVMCIObject message = JVMCIENV->wrap(jmessage);
    CompilerEvent::InlineEvent::post(event, compileId, caller_method, callee_method, 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) {

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

Event fields with their types and descriptions
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
Example event data values and properties
bci int
5
callee CalleeMethod
descriptor string
(II)V
name string
checkIndex
type string
java/lang/String
caller Method
descriptor string
(I[B)V
hidden boolean
false
modifiers int
9
name string
checkIndex
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
16
name string
java/lang/StringUTF16
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
compileId uint
1406
message string
inline
startTime long: millis
212959311
succeeded boolean
true
Example event data values and properties
bci int
49
callee CalleeMethod
descriptor string
([BBIIB)[B
name string
ensureCapacityNewCoder
type string
java/lang/AbstractStringBuilder
caller Method
descriptor string
(C)Ljava/lang/AbstractStringBuilder;
hidden boolean
false
modifiers int
1
name string
append
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1024
name string
java/lang/AbstractStringBuilder
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
compileId uint
92502
message string
already compiled into a medium method
startTime long: millis
541043043203
succeeded boolean
false
Example event data values and properties
bci int
12
callee CalleeMethod
descriptor string
()Z
name string
booleanValue
type string
java/lang/Boolean
caller Method
descriptor string
(Ljava/lang/Object;)Z
hidden boolean
false
modifiers int
9
name string
unboxToBoolean
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
scala/runtime/BoxesRunTime
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/runtime
compileId uint
93474
message string
inline
startTime long: millis
267233126864
succeeded boolean
true

Deoptimization

profiling default startTime eventThread stackTrace 14 17 21 25 27 28

Category: Java Virtual Machine / Compiler

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

Missing in: graalvm_linux_native

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

Code Context

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

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

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

static void post_deoptimization_event(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();
  }
}

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

Event fields with their types and descriptions
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
Example event data values and properties
action DeoptimizationAction
reinterpret
bci int
84
compileId uint
95639
compiler CompilerType
c2
instruction Bytecode
ifne
lineNumber int
71
method Method
descriptor string
(Ldotty/tools/dotc/core/Names$SimpleName;)Ldotty/tools/dotc/core/Names$SimpleName;
hidden boolean
false
modifiers int
1
name string
encode
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
dotty/tools/dotc/util/NameTransformer$
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
dotty/tools/dotc/util
reason DeoptimizationReason
unstable_if
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
84
lineNumber int
71
method Method
descriptor string
(Ldotty/tools/dotc/core/Names$SimpleName;)Ldotty/tools/dotc/core/Names$SimpleName;
hidden boolean
false
modifiers int
1
name string
encode
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
dotty/tools/dotc/util/NameTransformer$
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
dotty/tools/dotc/util
type FrameType
JIT compiled
…
truncated boolean
true
startTime long: millis
587645663274
Example event data values and properties
action DeoptimizationAction
maybe_recompile
bci int
7
compileId uint
95015
compiler CompilerType
c2
instruction Bytecode
invokeinterface
lineNumber int
102
method Method
descriptor string
()Lscala/collection/Iterator;
hidden boolean
false
modifiers int
1
name string
iterator
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
9
name string
scala/collection/convert/JavaCollectionWrappers$JCollectionWrapper
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection/convert
reason DeoptimizationReason
bimorphic_or_optimized_type_check
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
102
method Method
descriptor string
()Lscala/collection/Iterator;
hidden boolean
false
modifiers int
1
name string
iterator
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
9
name string
scala/collection/convert/JavaCollectionWrappers$JCollectionWrapper
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection/convert
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
283613923885
Example event data values and properties
action DeoptimizationAction
maybe_recompile
bci int
4
compileId uint
1309
compiler CompilerType
c2
instruction Bytecode
invokeinterface
lineNumber int
1080
method Method
descriptor string
()Ljava/lang/Object;
hidden boolean
false
modifiers int
1
name string
next
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/util/Collections$UnmodifiableCollection$1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
reason DeoptimizationReason
class_check
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
4
lineNumber int
1080
method Method
descriptor string
()Ljava/lang/Object;
hidden boolean
false
modifiers int
1
name string
next
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/util/Collections$UnmodifiableCollection$1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
223627826

CompilerStatistics

profiling default startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Compiler

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

Missing in: graalvm_linux_native

Code Context

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

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

TRACE_REQUEST_FUNC(LoaderConstraintsTableStatistics) {
  TableStatistics statistics = SystemDictionary::loader_constraints_statistics();
  emit_table_statistics<EventLoaderConstraintsTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(ProtectionDomainCacheTableStatistics) {
  TableStatistics statistics = SystemDictionary::protection_domain_cache_statistics();
  emit_table_statistics<EventProtectionDomainCacheTableStatistics>(statistics);
}

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

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

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

Examples 3
Example event data values and properties
bailoutCount int
10
compileCount int
94129
invalidatedCount int
0
nmethodCodeSize ulong: bytes
143806536
nmethodsSize ulong: bytes
203051272
osrBytesCompiled ulong: bytes
0
osrCompileCount int
1033
peakTimeSpent long: millis
9556
standardBytesCompiled ulong: bytes
0
standardCompileCount int
93096
startTime long: millis
282402522476
totalTimeSpent long: millis
230010
Example event data values and properties
bailoutCount int
4
compileCount int
2942
invalidatedCount int
0
nmethodCodeSize ulong: bytes
3884592
nmethodsSize ulong: bytes
5254824
osrBytesCompiled ulong: bytes
0
osrCompileCount int
19
peakTimeSpent long: millis
78
standardBytesCompiled ulong: bytes
0
standardCompileCount int
2923
startTime long: millis
8393350031
totalTimeSpent long: millis
1677
Example event data values and properties
bailoutCount int
9
compileCount int
91309
invalidatedCount int
0
nmethodCodeSize ulong: bytes
130050040
nmethodsSize ulong: bytes
187284360
osrBytesCompiled ulong: bytes
0
osrCompileCount int
1013
peakTimeSpent long: millis
23164
standardBytesCompiled ulong: bytes
0
standardCompileCount int
90296
startTime long: millis
543124005327
totalTimeSpent long: millis
885269

CompilerConfiguration

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

Category: Java Virtual Machine / Compiler

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

Missing in: graalvm_linux_native

Code Context

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

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

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

TRACE_REQUEST_FUNC(CompilerConfiguration) {
  EventCompilerConfiguration event;
  event.set_threadCount(CICompilerCount);
  event.set_tieredCompilation(TieredCompilation);
  event.commit();
}

TRACE_REQUEST_FUNC(CodeCacheStatistics) {
  // Emit stats for all available code heaps
  for (int bt = 0; bt < CodeBlobType::NumTypes; ++bt) {
    if (CodeCache::heap_available(bt)) {
      EventCodeCacheStatistics event;
      event.set_codeBlobType((u1)bt);

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

Event fields with their types and descriptions
Field Type Description
threadCount int Thread Count
tieredCompilation boolean Tiered Compilation

Examples 3
Example event data values and properties
startTime long: millis
24562793899
threadCount int
3
tieredCompilation boolean
true
Example event data values and properties
startTime long: millis
282253408221
threadCount int
3
tieredCompilation boolean
true
Example event data values and properties
startTime long: millis
601783523990
threadCount int
3
tieredCompilation boolean
true

JVM: Diagnostics

SyncOnValueBasedClass

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

Category: Java Virtual Machine / Diagnostics

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

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

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

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

Examples 3
Example event data values and properties
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
56
lineNumber int
300
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
triggerSyncOnValueBased
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1319956808
valueBasedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Long
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
Example event data values and properties
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
56
lineNumber int
300
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
triggerSyncOnValueBased
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1238863092
valueBasedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Long
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
Example event data values and properties
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
56
lineNumber int
300
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
triggerSyncOnValueBased
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
875278730
valueBasedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Long
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang

HeapDump

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

Category: Java Virtual Machine / Diagnostics

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

The event is likely defined and utilized 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:

// dump the heap to given path.
int HeapDumper::dump(const char* path, outputStream* out, int compression, bool overwrite) {
  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;
    }
  }

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

Event fields with their types and descriptions
Field Type Description
destination string Destination
size long Size
gcBeforeDump boolean GC Before Dump
onOutOfMemoryError boolean On Out of Memory Error

Examples 3
Example event data values and properties
destination string
/tmp/jfr_sample_heap_700456415131.hprof
gcBeforeDump boolean
true
onOutOfMemoryError boolean
false
size long
14464670
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/String;Z)V
hidden boolean
false
modifiers int
258
name string
dumpHeap0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
com/sun/management/internal/HotSpotDiagnostic
package Package
exported boolean
false
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.management
name string
jdk.management
version string
25.0.4.1
name string
com/sun/management/internal
type FrameType
Native
…
truncated boolean
false
startTime long: millis
1364605779
Example event data values and properties
destination string
/tmp/jfr_sample_heap_507727863526.hprof
gcBeforeDump boolean
true
onOutOfMemoryError boolean
false
size long
16468525
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/String;Z)V
hidden boolean
false
modifiers int
258
name string
dumpHeap0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
com/sun/management/internal/HotSpotDiagnostic
package Package
exported boolean
false
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.management
name string
jdk.management
version string
25.0.4.1
name string
com/sun/management/internal
type FrameType
Native
…
truncated boolean
false
startTime long: millis
879562850
Example event data values and properties
destination string
/tmp/jfr_sample_heap_824674559023.hprof
gcBeforeDump boolean
true
onOutOfMemoryError boolean
false
size long
14299634
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/String;Z)V
hidden boolean
false
modifiers int
258
name string
dumpHeap0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
com/sun/management/internal/HotSpotDiagnostic
package Package
exported boolean
false
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.management
name string
jdk.management
version string
25.0.4.1
name string
com/sun/management/internal
type FrameType
Native
…
truncated boolean
false
startTime long: millis
1243446148

JVM: Flag

IntFlagChanged

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
name string
HeapDumpGzipLevel
newValue int
0
oldValue int
1
origin FlagValueOrigin
Management
startTime long: millis
1275522965
Example event data values and properties
name string
HeapDumpGzipLevel
newValue int
1
oldValue int
0
origin FlagValueOrigin
Management
startTime long: millis
1203707630
Example event data values and properties
name string
HeapDumpGzipLevel
newValue int
1
oldValue int
0
origin FlagValueOrigin
Management
startTime long: millis
846668586

UnsignedIntFlagChanged

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

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

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

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

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

Examples 3
Example event data values and properties
name string
FullGCHeapDumpLimit
newValue uint
0
oldValue uint
1
origin FlagValueOrigin
Management
startTime long: millis
1203798642
Example event data values and properties
name string
FullGCHeapDumpLimit
newValue uint
0
oldValue uint
1
origin FlagValueOrigin
Management
startTime long: millis
1275575454
Example event data values and properties
name string
FullGCHeapDumpLimit
newValue uint
1
oldValue uint
0
origin FlagValueOrigin
Management
startTime long: millis
846743028

LongFlagChanged

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

Code Context

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

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

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

class FlagAccessImpl_intx : public RangedFlagAccessImpl<intx, EventLongFlagChanged> {
public:
  void range_error(const char* name, intx value, intx min, intx max, bool verbose) const {
    JVMFlag::printError(verbose,
                        "intx %s=" 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 {

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

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

UnsignedLongFlagChanged

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

                        name, value, min, max);
  }
  JVMFlag::Error typed_check_constraint(void* func, intx value, bool verbose) const {
    return ((JVMFlagConstraintFunc_intx)func)(value, verbose);
  }
  void print_range_impl(outputStream* st, intx min, intx max) const {
    st->print("[ " 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 {

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

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

Examples 3
Example event data values and properties
name string
MaxHeapFreeRatio
newValue ulong
75
oldValue ulong
100
origin FlagValueOrigin
Management
startTime long: millis
1203444045
Example event data values and properties
name string
MinHeapFreeRatio
newValue ulong
45
oldValue ulong
40
origin FlagValueOrigin
Management
startTime long: millis
846519281
Example event data values and properties
name string
MinHeapFreeRatio
newValue ulong
45
oldValue ulong
40
origin FlagValueOrigin
Management
startTime long: millis
1275218172

DoubleFlagChanged

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

                        name, value, min, max);
  }
  JVMFlag::Error typed_check_constraint(void* func, size_t value, bool verbose) const {
    return ((JVMFlagConstraintFunc_size_t)func)(value, verbose);
  }
  void print_range_impl(outputStream* st, size_t min, size_t max) const {
    st->print("[ " 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 {

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

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

Examples 3
Example event data values and properties
name string
G1PeriodicGCSystemLoadThreshold
newValue double
0.5
oldValue double
0.0
origin FlagValueOrigin
Management
startTime long: millis
1203646265
Example event data values and properties
name string
G1PeriodicGCSystemLoadThreshold
newValue double
0.0
oldValue double
0.5
origin FlagValueOrigin
Management
startTime long: millis
846655516
Example event data values and properties
name string
G1PeriodicGCSystemLoadThreshold
newValue double
0.5
oldValue double
0.0
origin FlagValueOrigin
Management
startTime long: millis
1275420122

BooleanFlagChanged

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

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

    return JVMFlag::SUCCESS;
  }

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
name string
PrintConcurrentLocks
newValue boolean
false
oldValue boolean
true
origin FlagValueOrigin
Management
startTime long: millis
846475675
Example event data values and properties
name string
PrintConcurrentLocks
newValue boolean
true
oldValue boolean
false
origin FlagValueOrigin
Management
startTime long: millis
1275088097
Example event data values and properties
name string
PrintConcurrentLocks
newValue boolean
true
oldValue boolean
false
origin FlagValueOrigin
Management
startTime long: millis
1203271511

StringFlagChanged

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

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.

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

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

Examples 3
Example event data values and properties
name string
HeapDumpPath
newValue string
/tmp/jfr_heap
oldValue string
null
origin FlagValueOrigin
Management
startTime long: millis
846590228
Example event data values and properties
name string
HeapDumpPath
newValue string
/tmp/jfr_heap
oldValue string
null
origin FlagValueOrigin
Management
startTime long: millis
1203545035
Example event data values and properties
name string
HeapDumpPath
newValue string
/tmp/jfr_heap
oldValue string
null
origin FlagValueOrigin
Management
startTime long: millis
1275346764

IntFlag

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

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_native

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

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

Examples 3
Example event data values and properties
name string
AllocatePrefetchLines
origin FlagValueOrigin
Default
startTime long: millis
213747596
value int
3
Example event data values and properties
name string
UseAVX
origin FlagValueOrigin
Default
startTime long: millis
267898506895
value int
3
Example event data values and properties
name string
ObjectAlignmentInBytes
origin FlagValueOrigin
Default
startTime long: millis
540789585671
value int
8

UnsignedIntFlag

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

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_native

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

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

Examples 3
Example event data values and properties
name string
HeapDumpParallelism
origin FlagValueOrigin
Default
startTime long: millis
542876445314
value uint
0
Example event data values and properties
name string
ErrorHandlerTest
origin FlagValueOrigin
Default
startTime long: millis
5532964675
value uint
0
Example event data values and properties
name string
SurvivorPadding
origin FlagValueOrigin
Default
startTime long: millis
267898525253
value uint
3

LongFlag

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

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_native

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

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

Examples 3
Example event data values and properties
name string
ConditionalMoveLimit
origin FlagValueOrigin
Default
startTime long: millis
267898532484
value long
3
Example event data values and properties
name string
MaxBCEAEstimateLevel
origin FlagValueOrigin
Default
startTime long: millis
540789629063
value long
5
Example event data values and properties
name string
TrackedInitializationLimit
origin FlagValueOrigin
Default
startTime long: millis
213778152
value long
50

UnsignedLongFlag

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

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_native

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

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

Examples 3
Example event data values and properties
name string
AdaptiveSizePolicyReadyThreshold
origin FlagValueOrigin
Default
startTime long: millis
213802428
value ulong
5
Example event data values and properties
name string
G1MaxVerifyFailures
origin FlagValueOrigin
Default
startTime long: millis
267898561518
value ulong
-1
Example event data values and properties
name string
AdaptiveSizeMajorGCDecayTimeScale
origin FlagValueOrigin
Default
startTime long: millis
540789649221
value ulong
10

DoubleFlag

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

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_native

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

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

Examples 3
Example event data values and properties
name string
InlineFrequencyRatio
origin FlagValueOrigin
Default
startTime long: millis
213818383
value double
0.25
Example event data values and properties
name string
InitialRAMPercentage
origin FlagValueOrigin
Default
startTime long: millis
269314089624
value double
1.5625
Example event data values and properties
name string
ZCollectionInterval
origin FlagValueOrigin
Default
startTime long: millis
549140714942
value double
0.0

BooleanFlag

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

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_native

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

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

Examples 3
Example event data values and properties
name string
BailoutAfterHIR
origin FlagValueOrigin
Default
startTime long: millis
267898576861
value boolean
false
Example event data values and properties
name string
PrintCommandLineFlags
origin FlagValueOrigin
Default
startTime long: millis
540789721897
value boolean
false
Example event data values and properties
name string
C1ProfileVirtualCalls
origin FlagValueOrigin
Default
startTime long: millis
213830200
value boolean
true

StringFlag

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

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_native

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

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

Examples 3
Example event data values and properties
name string
LogClassLoadingCauseFor
origin FlagValueOrigin
Default
startTime long: millis
542876587171
value string
null
Example event data values and properties
name string
MallocTraceDumpOutput
origin FlagValueOrigin
Default
startTime long: millis
213897412
value string
stderr
Example event data values and properties
name string
InlineDataFile
origin FlagValueOrigin
Default
startTime long: millis
269314140220
value string
null

JVM: GC: Collector

GarbageCollection

profiling default startTime duration graal vm only

Category: Java Virtual Machine / GC / Collector

Garbage collection performed by the JVM

Code Context

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

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

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

typedef uintptr_t TraceAddress;

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

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

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

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

Examples 3
Example event data values and properties
cause GCCause
G1 Evacuation Pause
gcId uint
1093
longestPause Tickspan
3185230
name GCName
G1New
startTime long: millis
279823143805
sumOfPauses Tickspan
3185230
Example event data values and properties
cause GCCause
G1 Evacuation Pause
gcId uint
65
longestPause Tickspan
788851
name GCName
G1New
startTime long: millis
1340855028
sumOfPauses Tickspan
788851
Example event data values and properties
cause GCCause
Heap Inspection Initiated GC
gcId uint
350
longestPause Tickspan
240324190
name GCName
ParallelOld
startTime long: millis
542879611178
sumOfPauses Tickspan
240324190

SystemGC

profiling default startTime duration eventThread stackTrace 17 21 25 27 28 graal vm

Category: Java Virtual Machine / GC / Collector

Code Context

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

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

    event.commit();
  }
JVM_END


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


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


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

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

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

Examples 3
Example event data values and properties
invokedConcurrent boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
257
name string
gc
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Runtime
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
295108788475
Example event data values and properties
invokedConcurrent boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
257
name string
gc
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Runtime
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
599187561993
Example event data values and properties
invokedConcurrent boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
257
name string
gc
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Runtime
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
2280483498

ParallelOldGarbageCollection

profiling default startTime duration 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Collector

Appearing in: linux_ParallelGC

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

Extra information specific to Parallel Old Garbage Collections

Code Context

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

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

    e.set_smallChunksTotalSize(summary.small_chunks_size_in_bytes());

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

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

    e.commit();
  }
}

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

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

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

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

Examples 2
Example event data values and properties
densePrefix ulong: address
30173822976
gcId uint
52
startTime long: millis
1930835362
Example event data values and properties
densePrefix ulong: address
30413422592
gcId uint
389
startTime long: millis
608941593474

YoungGarbageCollection

profiling default startTime duration 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Collector

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

Extra information specific to Young Garbage Collections

Code Context

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
gcId uint
1
startTime long: millis
375121112
tenuringThreshold uint
15
Example event data values and properties
gcId uint
388
startTime long: millis
607230144978
tenuringThreshold uint
1
Example event data values and properties
gcId uint
1123
startTime long: millis
284851331496
tenuringThreshold uint
15

OldGarbageCollection

profiling default startTime duration 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Collector

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

Extra information specific to Old Garbage Collections

Code Context

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
gcId uint
1023
startTime long: millis
269316313246
Example event data values and properties
gcId uint
140
startTime long: millis
1904197112
Example event data values and properties
gcId uint
354
startTime long: millis
549142293399

G1GarbageCollection

profiling default startTime duration 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Collector

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Extra information specific to G1 Young Garbage Collections

Code Context

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

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

  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(G1EvacuationInfo* info) {
  EventEvacuationInformation e;

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

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

Examples 3
Example event data values and properties
gcId uint
14
startTime long: millis
574374620
type G1YCType
Normal
Example event data values and properties
gcId uint
1026
startTime long: millis
269597494643
type G1YCType
Concurrent Start
Example event data values and properties
gcId uint
1164
startTime long: millis
472141338748
type G1YCType
Normal

JVM: GC: Configuration

GCConfiguration

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

Category: Java Virtual Machine / GC / Configuration

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

Missing in: graalvm_linux_native

The configuration of the garbage collector

Code Context

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
concurrentGCThreads uint
1
gcTimeRatio uint
12
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
G1Old
parallelGCThreads uint
4
pauseTarget long: millis
-9223372036854775808
startTime long: millis
281896848328
usesDynamicGCThreads boolean
true
youngCollector GCName
G1New
Example event data values and properties
concurrentGCThreads uint
0
gcTimeRatio uint
99
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
ParallelOld
parallelGCThreads uint
4
pauseTarget long: millis
-9223372036854775808
startTime long: millis
547566404634
usesDynamicGCThreads boolean
true
youngCollector GCName
ParallelScavenge
Example event data values and properties
concurrentGCThreads uint
1
gcTimeRatio uint
12
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
G1Old
parallelGCThreads uint
4
pauseTarget long: millis
-9223372036854775808
startTime long: millis
11702470491
usesDynamicGCThreads boolean
true
youngCollector GCName
G1New

GCSurvivorConfiguration

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

Category: Java Virtual Machine / GC / Configuration

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

Missing in: graalvm_linux_native

The configuration of the survivors of garbage collection

Code Context

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

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

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

TRACE_REQUEST_FUNC(GCSurvivorConfiguration) {
  GCSurvivorConfiguration conf;
  EventGCSurvivorConfiguration event;
  event.set_maxTenuringThreshold(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 configuration settings across JFR profiles
Configuration enabled period
profiling true beginChunk
default true beginChunk

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

Examples 3
Example event data values and properties
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
221050203
Example event data values and properties
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
553580274308
Example event data values and properties
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
268062221901

GCTLABConfiguration

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

Category: Java Virtual Machine / GC / Configuration

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

Missing in: graalvm_linux_native

The configuration of the Thread Local Allocation Buffers (TLABs)

Code Context

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

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

  event.set_oldCollector(conf.old_collector());
  event.set_parallelGCThreads(conf.num_parallel_gc_threads());
  event.set_concurrentGCThreads(conf.num_concurrent_gc_threads());
  event.set_usesDynamicGCThreads(conf.uses_dynamic_gc_threads());
  event.set_isExplicitGCConcurrent(conf.is_explicit_gc_concurrent());
  event.set_isExplicitGCDisabled(conf.is_explicit_gc_disabled());
  event.set_gcTimeRatio(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());

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

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

Examples 3
Example event data values and properties
minTLABSize ulong: bytes
2048
startTime long: millis
296789205430
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
Example event data values and properties
minTLABSize ulong: bytes
2048
startTime long: millis
571634900940
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
Example event data values and properties
minTLABSize ulong: bytes
2048
startTime long: millis
18051453581
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true

GCHeapConfiguration

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

Category: Java Virtual Machine / GC / Configuration

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

Missing in: graalvm_linux_native

The configuration of the garbage collected heap

Code Context

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

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

  event.commit();
}

TRACE_REQUEST_FUNC(GCSurvivorConfiguration) {
  GCSurvivorConfiguration conf;
  EventGCSurvivorConfiguration event;
  event.set_maxTenuringThreshold(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) {

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

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

Examples 3
Example event data values and properties
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
262144000
maxSize ulong: bytes
4192206848
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
590493275345
usesCompressedOops boolean
true
Example event data values and properties
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
262144000
maxSize ulong: bytes
4192206848
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
24589844367
usesCompressedOops boolean
true
Example event data values and properties
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
262144000
maxSize ulong: bytes
4192206848
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
282402204696
usesCompressedOops boolean
true

YoungGenerationConfiguration

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

Category: Java Virtual Machine / GC / Configuration

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

Missing in: graalvm_linux_native

The configuration of the young generation of the garbage collected heap

Code Context

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

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

  event.set_minSize(conf.min_size());
  event.set_maxSize(conf.max_size());
  event.set_initialSize(conf.initial_size());
  event.set_usesCompressedOops(conf.uses_compressed_oops());
  event.set_compressedOopsMode(conf.narrow_oop_mode());
  event.set_objectAlignment(conf.object_alignment_in_bytes());
  event.set_heapAddressBits(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()) {

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

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

Examples 3
Example event data values and properties
maxSize ulong: bytes
2514485248
minSize ulong: bytes
1363144
newRatio uint
2
startTime long: millis
24589845398
Example event data values and properties
maxSize ulong: bytes
2514485248
minSize ulong: bytes
1363144
newRatio uint
2
startTime long: millis
272319211512
Example event data values and properties
maxSize ulong: bytes
1396703232
minSize ulong: bytes
85983232
newRatio uint
2
startTime long: millis
593786427880

JVM: GC: Detailed

G1MMU

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Code Context

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

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
gcId uint
1129
gcTime long: millis
6
pauseTarget long: millis
200
startTime long: millis
462989788977
timeSlice long: millis
201
Example event data values and properties
gcId uint
1084
gcTime long: millis
8
pauseTarget long: millis
200
startTime long: millis
278600446521
timeSlice long: millis
201
Example event data values and properties
gcId uint
120
gcTime long: millis
7
pauseTarget long: millis
200
startTime long: millis
1757796372
timeSlice long: millis
201

EvacuationInformation

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Code Context

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

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

  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(G1EvacuationInfo* 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();

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

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

Examples 3
Example event data values and properties
allocationRegions uint
1
allocationRegionsUsedAfter ulong: bytes
92424
allocationRegionsUsedBefore ulong: bytes
0
bytesCopied ulong: bytes
92424
cSetRegions uint
4
cSetUsedAfter ulong: bytes
0
cSetUsedBefore ulong: bytes
7366456
gcId uint
1142
regionsFreed uint
4
startTime long: millis
465466639683
Example event data values and properties
allocationRegions uint
3
allocationRegionsUsedAfter ulong: bytes
4202528
allocationRegionsUsedBefore ulong: bytes
0
bytesCopied ulong: bytes
4202528
cSetRegions uint
9
cSetUsedAfter ulong: bytes
0
cSetUsedBefore ulong: bytes
18500816
gcId uint
23
regionsFreed uint
9
startTime long: millis
923842898
Example event data values and properties
allocationRegions uint
1
allocationRegionsUsedAfter ulong: bytes
139200
allocationRegionsUsedBefore ulong: bytes
0
bytesCopied ulong: bytes
139200
cSetRegions uint
7
cSetUsedAfter ulong: bytes
0
cSetUsedBefore ulong: bytes
12594632
gcId uint
1096
regionsFreed uint
7
startTime long: millis
280217722170

ObjectCountAfterGC

startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

Code Context

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

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

#if INCLUDE_SERVICES

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

bool ObjectCountEventSender::_should_send_requestable_event = false;

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

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_gcId(GCId::current());
    event.set_objectClass(klass);
    event.set_count(count);
    event.set_totalSize(size);
    event.set_endtime(timestamp);
    event.commit();
  }
}

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

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

#endif // INCLUDE_SERVICES

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

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

Examples 3
Example event data values and properties
count long
556
gcId uint
0
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[Ljava/lang/String;
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
startTime long: millis
217929250
totalSize ulong: bytes
21456
Example event data values and properties
count long
176503
gcId uint
348
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
startTime long: millis
540953276747
totalSize ulong: bytes
1412024
Example event data values and properties
count long
68850
gcId uint
1020
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
25.0.4.1
name string
java/util
startTime long: millis
269088427565
totalSize ulong: bytes
1652400

G1EvacuationYoungStatistics

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Memory related evacuation statistics during GC for the young generation

Code Context

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
startTime long: millis
462268514740
statistics G1EvacuationStatistics
allocated ulong: bytes
1777840
directAllocated ulong: bytes
1422928
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1127
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
2
undoWaste ulong: bytes
0
used ulong: bytes
1688088
wasted ulong: bytes
12624
Example event data values and properties
startTime long: millis
268094894631
statistics G1EvacuationStatistics
allocated ulong: bytes
96800
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1015
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
1
undoWaste ulong: bytes
0
used ulong: bytes
73304
wasted ulong: bytes
112
Example event data values and properties
startTime long: millis
2201655315
statistics G1EvacuationStatistics
allocated ulong: bytes
2097152
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
180
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
1
undoWaste ulong: bytes
0
used ulong: bytes
2028152
wasted ulong: bytes
69000

G1EvacuationOldStatistics

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Memory related evacuation statistics during GC for the old generation

Code Context

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

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

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

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

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

void G1NewTracer::send_basic_ihop_statistics(size_t threshold,
                                             size_t target_occupancy,
                                             size_t current_occupancy,
                                             size_t last_allocation_size,
                                             double last_allocation_duration,

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

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

Examples 3
Example event data values and properties
startTime long: millis
473209211724
statistics G1EvacuationStatistics
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1166
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
0
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0
Example event data values and properties
startTime long: millis
268094896393
statistics G1EvacuationStatistics
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1015
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
0
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0
Example event data values and properties
startTime long: millis
1562752190
statistics G1EvacuationStatistics
allocated ulong: bytes
4096
directAllocated ulong: bytes
4157232
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
94
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
48
regionsRefilled uint
2
undoWaste ulong: bytes
0
used ulong: bytes
4056
wasted ulong: bytes
0

G1BasicIHOP

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Basic statistics related to current IHOP calculation

Code Context

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

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

  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();

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

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
threshold ulong: bytes Current IHOP Threshold Current IHOP threshold
thresholdPercentage float: percentage Current IHOP Threshold Current IHOP threshold in percent of old generation
targetOccupancy ulong: bytes Target Occupancy Target old generation occupancy to reach at the start of mixed GC
currentOccupancy ulong: bytes Current Occupancy Current old generation occupancy
recentMutatorAllocationSize ulong: bytes 11 17 21 25 until JDK 27 Recent Mutator Allocation Size Mutator allocation during mutator operation in the most recent interval
recentMutatorDuration long: millis 11 17 21 25 until JDK 27 Recent Mutator Duration Time the mutator ran in the most recent interval
recentAllocationRate double: bytes-per-second 11 17 21 25 until JDK 27 Recent Allocation Rate Allocation rate of the mutator in the most recent interval in bytes/second
lastMarkingDuration long: millis 11 17 21 25 until JDK 27 Last Marking Duration Last time from the end of the last concurrent start to the first mixed GC

Examples 3
Example event data values and properties
currentOccupancy ulong: bytes
13879184
gcId uint
206
lastMarkingDuration long: millis
43
recentAllocationRate double: bytes-per-second
3.6571742992201753E9
recentMutatorAllocationSize ulong: bytes
3084000
recentMutatorDuration long: millis
0
startTime long: millis
2415469220
targetOccupancy ulong: bytes
29360128
threshold ulong: bytes
13212057
thresholdPercentage float: percentage
0.45
Example event data values and properties
currentOccupancy ulong: bytes
290046368
gcId uint
1166
lastMarkingDuration long: millis
1404
recentAllocationRate double: bytes-per-second
0.0
recentMutatorAllocationSize ulong: bytes
0
recentMutatorDuration long: millis
511
startTime long: millis
473209242021
targetOccupancy ulong: bytes
2218786816
threshold ulong: bytes
337385821
thresholdPercentage float: percentage
0.15205869
Example event data values and properties
currentOccupancy ulong: bytes
592194376
gcId uint
1084
lastMarkingDuration long: millis
628
recentAllocationRate double: bytes-per-second
2.691982589276779E8
recentMutatorAllocationSize ulong: bytes
120445400
recentMutatorDuration long: millis
447
startTime long: millis
278600455705
targetOccupancy ulong: bytes
861929472
threshold ulong: bytes
73358264
thresholdPercentage float: percentage
0.08510936

G1AdaptiveIHOP

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Statistics related to current adaptive IHOP calculation

Code Context

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

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

    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();

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

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
threshold ulong: bytes Threshold Current IHOP Threshold
thresholdPercentage float: percentage Threshold Current IHOP threshold in percent of the internal target occupancy
ihopTargetOccupancy ulong: bytes IHOP Target Occupancy Internal target old generation occupancy to reach at the start of mixed GC
currentOccupancy ulong: bytes Current Occupancy Current old generation occupancy
additionalBufferSize ulong: bytes Additional Buffer Additional buffer size
predictedAllocationRate double: bytes-per-second 11 17 21 25 until JDK 27 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 3
Example event data values and properties
additionalBufferSize ulong: bytes
331350016
currentOccupancy ulong: bytes
479245800
gcId uint
1083
ihopTargetOccupancy ulong: bytes
814848409
predictedAllocationRate double: bytes-per-second
3.077763095773205E8
predictedMarkingDuration long: millis
1370
predictionActive boolean
true
startTime long: millis
278415009748
threshold ulong: bytes
61698331
thresholdPercentage float: percentage
0.07571755
Example event data values and properties
additionalBufferSize ulong: bytes
524288000
currentOccupancy ulong: bytes
299781672
gcId uint
1172
ihopTargetOccupancy ulong: bytes
870632652
predictedAllocationRate double: bytes-per-second
2.054257297980973E8
predictedMarkingDuration long: millis
2074
predictionActive boolean
true
startTime long: millis
480162316509
threshold ulong: bytes
0
thresholdPercentage float: percentage
0.0
Example event data values and properties
additionalBufferSize ulong: bytes
18874368
currentOccupancy ulong: bytes
9325928
gcId uint
21
ihopTargetOccupancy ulong: bytes
33869004
predictedAllocationRate double: bytes-per-second
6.318052276629703E8
predictedMarkingDuration long: millis
87
predictionActive boolean
false
startTime long: millis
867720537
threshold ulong: bytes
16043212
thresholdPercentage float: percentage
0.4736842

PromoteObjectInNewPLAB

profiling startTime eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC

Missing in: graalvm_linux_native, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

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

Code Context

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

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

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
gcId uint
1
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/String
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
objectSize ulong: bytes
24
plabSize ulong: bytes
16384
startTime long: millis
376098703
tenured boolean
true
tenuringAge uint
0
Example event data values and properties
gcId uint
1019
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[D
package Package
null
objectSize ulong: bytes
80
plabSize ulong: bytes
16832
startTime long: millis
268827507264
tenured boolean
false
tenuringAge uint
0
Example event data values and properties
gcId uint
362
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
7528
plabSize ulong: bytes
32760
startTime long: millis
564059249631
tenured boolean
false
tenuringAge uint
0

PromoteObjectOutsidePLAB

profiling startTime eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC

Missing in: graalvm_linux_native, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

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

Code Context

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

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

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

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

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

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

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

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

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

void OldGCTracer::send_old_gc_event() const {

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

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

Examples 3
Example event data values and properties
gcId uint
1
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
objectSize ulong: bytes
4112
startTime long: millis
375638628
tenured boolean
false
tenuringAge uint
0
Example event data values and properties
gcId uint
1019
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
21352
startTime long: millis
268828558061
tenured boolean
false
tenuringAge uint
0
Example event data values and properties
gcId uint
371
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1040
name string
[Ljava/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
25.0.4.1
name string
java/util
objectSize ulong: bytes
32784
startTime long: millis
580677955787
tenured boolean
false
tenuringAge uint
0

PromotionFailed

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Promotion of an object failed

Code Context

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

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

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

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

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

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

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

EvacuationFailed

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Evacuation of an object failed

Code Context

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

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

    e.set_cSetRegions(info->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();

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

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

ConcurrentModeFailure

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Concurrent Mode failed

Code Context

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
gcId uint
1351
startTime long: millis
12581288472
Example event data values and properties
gcId uint
1140
startTime long: millis
465425429929
Example event data values and properties
gcId uint
1102
startTime long: millis
281896864312

GCCPUTime

profiling default startTime 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

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

Code Context

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

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

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

typedef uintptr_t TraceAddress;

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

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

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

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

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

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

Examples 3
Example event data values and properties
gcId uint
1067
realTime ulong: nanos
9999999
startTime long: millis
275975463951
systemTime ulong: nanos
0
userTime ulong: nanos
9999999
Example event data values and properties
gcId uint
359
realTime ulong: nanos
330000000
startTime long: millis
557645687803
systemTime ulong: nanos
0
userTime ulong: nanos
870000000
Example event data values and properties
gcId uint
26
realTime ulong: nanos
9999999
startTime long: millis
960821955
systemTime ulong: nanos
0
userTime ulong: nanos
19999999

AllocationRequiringGC

startTime eventThread stackTrace 11 17 21 25 27 28 graal vm

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

Code Context

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
gcId uint
372
size ulong: bytes
64
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
51
lineNumber int
1396
method Method
descriptor string
(Ljava/lang/Class;I)Ljava/lang/Object;
hidden boolean
false
modifiers int
1
name string
allocateUninitializedArray
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
type FrameType
Inlined
…
truncated boolean
true
startTime long: millis
581186943400
Example event data values and properties
gcId uint
117
size ulong: bytes
524304
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
45
lineNumber int
496
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
allocateAndGC
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
1732597238
Example event data values and properties
gcId uint
1119
size ulong: bytes
16
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
177
method Method
descriptor string
(ILjava/util/stream/Sink;)Ljava/util/stream/Sink;
hidden boolean
false
modifiers int
0
name string
opWrapSink
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/util/stream/IntPipeline$1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/stream
type FrameType
JIT compiled
…
truncated boolean
true
startTime long: millis
284403340169

TenuringDistribution

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_ShenandoahGC, linux_ZGC

Code Context

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

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

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

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

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

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

Examples 3
Example event data values and properties
age uint
2
gcId uint
1019
size ulong: bytes
4208
startTime long: millis
268831019874
Example event data values and properties
age uint
8
gcId uint
0
size ulong: bytes
0
startTime long: millis
220827988
Example event data values and properties
age uint
5
gcId uint
1353
size ulong: bytes
0
startTime long: millis
566143850708

G1HeapRegionTypeChange

startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Information about a G1 heap region type change

Code Context

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

src/hotspot/share/gc/g1/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();
  }
}

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

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

Examples 3
Example event data values and properties
from G1HeapRegionType
Free
index uint
13
start ulong: address
30194794496
startTime long: millis
426070686
to G1HeapRegionType
Old
used ulong: bytes
0
Example event data values and properties
from G1HeapRegionType
Free
index uint
401
start ulong: address
31008489472
startTime long: millis
447986568941
to G1HeapRegionType
Eden
used ulong: bytes
0
Example event data values and properties
from G1HeapRegionType
Free
index uint
1023
start ulong: address
32312918016
startTime long: millis
268143485327
to G1HeapRegionType
Eden
used ulong: bytes
0

ObjectCount

startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

Code Context

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

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

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

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

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

#endif // INCLUDE_SERVICES

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

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

Examples 3
Example event data values and properties
count long
57273
gcId uint
1020
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/ArrayList
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
startTime long: millis
269088427565
totalSize ulong: bytes
1374552
Example event data values and properties
count long
5485
gcId uint
20
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
version string
25.0.4.1
name string
java/lang
startTime long: millis
852878144
totalSize ulong: bytes
340248
Example event data values and properties
count long
69437
gcId uint
351
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
25.0.4.1
name string
java/util
startTime long: millis
544536794788
totalSize ulong: bytes
1666488

G1HeapRegionInformation

startTime duration every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Information about a specific heap region in the G1 GC

Code Context

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

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

class DumpEventInfoClosure : public 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;
    G1CollectedHeap::heap()->heap_region_iterate(&c);

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

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

Examples 3
Example event data values and properties
index uint
1
start ulong: address
30169628672
startTime long: millis
221030193
type G1HeapRegionType
Old
used ulong: bytes
1106912
Example event data values and properties
index uint
95
start ulong: address
30366760960
startTime long: millis
447809752085
type G1HeapRegionType
Old
used ulong: bytes
2097128
Example event data values and properties
index uint
6
start ulong: address
30180114432
startTime long: millis
268061310639
type G1HeapRegionType
Old
used ulong: bytes
2097144

ZAllocationStall

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

Category: Java Virtual Machine / GC / Detailed

Time spent waiting for memory to become available

Code Context

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

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

  // 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);

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

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

ZPageAllocation

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

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

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

Allocation of a ZPage

Code Context

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

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

    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

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

Event fields with their types and descriptions
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 2
Example event data values and properties
committed ulong: bytes
0
nonBlocking boolean
false
size ulong: bytes
2097152
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
24
lineNumber int
494
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
allocateAndGC
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
768959466
type ZPageTypeType
Small
Example event data values and properties
committed ulong: bytes
0
nonBlocking boolean
false
size ulong: bytes
2097152
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
1
lineNumber int
273
method Method
descriptor string
(I)[D
hidden boolean
false
modifiers int
1
name string
newArray
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
25
name string
scala/reflect/ManifestFactory$DoubleManifest
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/reflect
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
594596007835
type ZPageTypeType
Small

ZRelocationSet

profiling default startTime duration eventThread 15 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

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

Code Context

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

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

ZRelocationSetSelector::ZRelocationSetSelector() :
    _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 {

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

Event fields with their types and descriptions
Field Type Description
total ulong: bytes Total
empty ulong: bytes Empty
relocate ulong: bytes 16+ Relocate

Examples 2
Example event data values and properties
empty ulong: bytes
0
relocate ulong: bytes
0
startTime long: millis
503638903
total ulong: bytes
0
Example event data values and properties
empty ulong: bytes
111149056
relocate ulong: bytes
1094488
startTime long: millis
632798393578
total ulong: bytes
190840832

ZRelocationSetGroup

profiling default startTime duration eventThread 15 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

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

Code Context

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

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

  // 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),

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

Event fields with their types and descriptions
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 2
Example event data values and properties
empty ulong: bytes
0
relocate ulong: bytes
0
startTime long: millis
1754697839
total ulong: bytes
0
type ZPageTypeType
Large
Example event data values and properties
empty ulong: bytes
2097152
relocate ulong: bytes
2605848
startTime long: millis
622531768405
total ulong: bytes
289406976
type ZPageTypeType
Small

ZStatisticsCounter

experimental startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

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

Code Context

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

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

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

void ZTracer::initialize() {
  assert(_tracer == NULL, "Already initialized");
  _tracer = new (ResourceObj::C_HEAP, mtGC) 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;

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) {

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

Event fields with their types and descriptions
Field Type Description
id ZStatisticsCounterType Id
increment ulong Increment
value ulong Value

Examples 2
Example event data values and properties
id ZStatisticsCounterType
Allocation Rate
increment ulong
2097152
startTime long: millis
594738166147
value ulong
117440512
Example event data values and properties
id ZStatisticsCounterType
Allocation Rate
increment ulong
2097152
startTime long: millis
728250083
value ulong
16777216

ZStatisticsSampler

experimental startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

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

Code Context

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

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

  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);

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 ZTraceThreadPhase::ZTraceThreadPhase(const char* name) :

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

Event fields with their types and descriptions
Field Type Description
id ZStatisticsSamplerType Id
value ulong Value

Examples 2
Example event data values and properties
id ZStatisticsSamplerType
Concurrent Roots ClassLoaderDataGraph
startTime long: millis
483595603
value ulong
99678
Example event data values and properties
id ZStatisticsSamplerType
JNI Critical Stall
startTime long: millis
596456033265
value ulong
174158

ZThreadPhase

experimental startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

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

Code Context

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

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

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

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

inline void ZTracer::report_stat_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 ZTraceThreadPhase::ZTraceThreadPhase(const char* name) :
    _start(Ticks::now()),
    _name(name) {}

inline ZTraceThreadPhase::~ZTraceThreadPhase() {
  ZTracer::tracer()->report_thread_phase(_name, _start, Ticks::now());
}

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

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

Examples 2
Example event data values and properties
gcId uint
256
name string
Concurrent Mark Root Colored
startTime long: millis
596542789933
Example event data values and properties
gcId uint
2
name string
Concurrent Mark Root Uncolored
startTime long: millis
1442841550

ZUncommit

profiling default startTime duration eventThread 15 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

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

Uncommitting of memory

Code Context

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

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

bool ZUncommitter::should_continue() const {
  ZLocker<ZConditionLock> locker(&_lock);
  return !_stop;
}

void ZUncommitter::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;

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

Event fields with their types and descriptions
Field Type Description
uncommitted ulong: bytes Uncommitted

Examples 1
Example event data values and properties
startTime long: millis
655958664668
uncommitted ulong: bytes
33554432

ZUnmap

profiling default startTime duration eventThread 17 21 until JDK 25

Category: Java Virtual Machine / GC / Detailed

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) {

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

Event fields with their types and descriptions
Field Type Description
unmapped ulong: bytes Unmapped

ShenandoahHeapRegionStateChange

startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ShenandoahGC

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

Information about a Shenandoah heap region state change

Code Context

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

src/hotspot/share/gc/shenandoah/shenandoahHeapRegion.cpp:

void ShenandoahHeapRegion::do_uncommit() {
  ShenandoahHeap* heap = ShenandoahHeap::heap();
  if (!heap->is_heap_region_special() && !os::uncommit_memory((char *) bottom(), RegionSizeBytes)) {
    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;
}

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

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

Examples 2
Example event data values and properties
from ShenandoahHeapRegionState
Empty Uncommitted
index uint
3614
start ulong: address
33957085184
startTime long: millis
731928788
to ShenandoahHeapRegionState
Regular
used ulong: bytes
0
Example event data values and properties
from ShenandoahHeapRegionState
Empty Committed
index uint
3004
start ulong: address
33317453824
startTime long: millis
571057382188
to ShenandoahHeapRegionState
Empty Uncommitted
used ulong: bytes
0

ShenandoahHeapRegionInformation

startTime duration every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ShenandoahGC

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

Information about a specific heap region in the Shenandoah GC

Code Context

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

src/hotspot/share/gc/shenandoah/shenandoahJfrSupport.cpp:

void ShenandoahJFRSupport::register_jfr_type_serializers() {
  JfrSerializer::register_serializer(TYPE_SHENANDOAHHEAPREGIONSTATE,
                                     true,
                                     new ShenandoahHeapRegionStateConstant());
}
#endif

class ShenandoahDumpHeapRegionInfoClosure : public ShenandoahHeapRegionClosure {
public:
  virtual void heap_region_do(ShenandoahHeapRegion* r) {
    EventShenandoahHeapRegionInformation evt;
    evt.set_index((unsigned) r->index());
    evt.set_state((u8)r->state());
    evt.set_start((uintptr_t)r->bottom());
    evt.set_used(r->used());
    evt.commit();
  }
};

void VM_ShenandoahSendHeapRegionInfoEvents::doit() {
  ShenandoahDumpHeapRegionInfoClosure c;
  ShenandoahHeap::heap()->heap_region_iterate(&c);

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

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

Examples 2
Example event data values and properties
index uint
56
start ulong: address
30226251776
startTime long: millis
572485591338
state ShenandoahHeapRegionState
Humongous Continuation
used ulong: bytes
16
Example event data values and properties
index uint
26
start ulong: address
30194794496
startTime long: millis
404813656
state ShenandoahHeapRegionState
Empty Committed
used ulong: bytes
0

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_lockCount(_jni_lock_count);
      event.set_stallCount(_stall_count);
      event.commit();
    }
    // reset
    _needs_gc_start_timestamp = Ticks();
    _jni_lock_count = 0;
    _stall_count = 0;

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
profiling true true 100 ms
default true true 1 s

Event fields with their types and descriptions
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 27 28 graal vm

Category: Java Virtual Machine / GC / Heap

Code Context

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

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

  space.set_used(summary.used());
  space.set_size(summary.size());
  return space;
}

class GCHeapSummaryEventSender : public GCHeapSummaryVisitor {
  GCWhen::Type _when;
 public:
  GCHeapSummaryEventSender(GCWhen::Type when) : _when(when) {}

  void visit(const GCHeapSummary* heap_summary) const {
    const VirtualSpaceSummary& heap_space = heap_summary->heap();

    EventGCHeapSummary e;
    if (e.should_commit()) {
      e.set_gcId(GCId::current());
      e.set_when((u1)_when);
      e.set_heapSpace(to_struct(heap_space));
      e.set_heapUsed(heap_summary->used());
      e.commit();
    }
  }

  void visit(const G1HeapSummary* g1_heap_summary) const {
    visit((GCHeapSummary*)g1_heap_summary);

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

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
when GCWhen When
heapSpace VirtualSpace struct Heap Space
heapUsed ulong: bytes Heap Used Bytes allocated by objects in the heap

Examples 3
Example event data values and properties
gcId uint
349
heapSpace VirtualSpace
committedEnd ulong: address
33550237696
committedSize ulong: bytes
3382706176
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
heapUsed ulong: bytes
241511832
startTime long: millis
542627650520
when GCWhen
After GC
Example event data values and properties
gcId uint
1030
heapSpace VirtualSpace
committedEnd ulong: address
31035752448
committedSize ulong: bytes
868220928
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
heapUsed ulong: bytes
254366696
startTime long: millis
270721581764
when GCWhen
After GC
Example event data values and properties
gcId uint
23
heapSpace VirtualSpace
committedEnd ulong: address
30203183104
committedSize ulong: bytes
35651584
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
heapUsed ulong: bytes
12913480
startTime long: millis
923844220
when GCWhen
After GC

MetaspaceSummary

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Heap

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

Missing in: graalvm_linux_native

Code Context

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

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

  GCHeapSummaryEventSender visitor(when);
  heap_summary.accept(&visitor);
}

static JfrStructMetaspaceSizes to_struct(const MetaspaceStats& sizes) {
  JfrStructMetaspaceSizes meta_sizes;
  meta_sizes.set_committed(sizes.committed());
  meta_sizes.set_used(sizes.used());
  meta_sizes.set_reserved(sizes.reserved());
  return meta_sizes;
}

void GCTracer::send_meta_space_summary_event(GCWhen::Type when, const MetaspaceSummary& meta_space_summary) const {
  EventMetaspaceSummary e;
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_when((u1) when);
    e.set_gcThreshold(meta_space_summary.capacity_until_GC());
    e.set_metaspace(to_struct(meta_space_summary.stats())); // total stats (class + nonclass)
    e.set_dataSpace(to_struct(meta_space_summary.stats().non_class_space_stats())); // "dataspace" aka non-class space
    e.set_classSpace(to_struct(meta_space_summary.stats().class_space_stats()));
    e.commit();
  }
}

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

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
when GCWhen When
gcThreshold ulong: bytes GC Threshold
metaspace MetaspaceSizes struct Total
dataSpace MetaspaceSizes struct Data
classSpace MetaspaceSizes struct Class

Examples 3
Example event data values and properties
classSpace MetaspaceSizes
committed ulong: bytes
176488448
reserved ulong: bytes
1073741824
used ulong: bytes
174875536
dataSpace MetaspaceSizes
committed ulong: bytes
767426560
reserved ulong: bytes
805306368
used ulong: bytes
765550080
gcId uint
1012
gcThreshold ulong: bytes
1573191680
metaspace MetaspaceSizes
committed ulong: bytes
943915008
reserved ulong: bytes
1879048192
used ulong: bytes
940425616
startTime long: millis
268059941307
when GCWhen
After GC
Example event data values and properties
classSpace MetaspaceSizes
committed ulong: bytes
188874752
reserved ulong: bytes
1073741824
used ulong: bytes
185322776
dataSpace MetaspaceSizes
committed ulong: bytes
809893888
reserved ulong: bytes
872415232
used ulong: bytes
807940168
gcId uint
388
gcThreshold ulong: bytes
1675689984
metaspace MetaspaceSizes
committed ulong: bytes
998768640
reserved ulong: bytes
1946157056
used ulong: bytes
993262944
startTime long: millis
607230164325
when GCWhen
Before GC
Example event data values and properties
classSpace MetaspaceSizes
committed ulong: bytes
3014656
reserved ulong: bytes
1073741824
used ulong: bytes
2865168
dataSpace MetaspaceSizes
committed ulong: bytes
12058624
reserved ulong: bytes
67108864
used ulong: bytes
11911200
gcId uint
34
gcThreshold ulong: bytes
25165824
metaspace MetaspaceSizes
committed ulong: bytes
15073280
reserved ulong: bytes
1140850688
used ulong: bytes
14776368
startTime long: millis
1035169692
when GCWhen
After GC

PSHeapSummary

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Heap

Appearing in: linux_ParallelGC

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

Code Context

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

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

  void visit(const PSHeapSummary* ps_heap_summary) const {
    visit((GCHeapSummary*)ps_heap_summary);

    const VirtualSpaceSummary& old_summary = ps_heap_summary->old();
    const SpaceSummary& old_space = ps_heap_summary->old_space();
    const VirtualSpaceSummary& young_summary = ps_heap_summary->young();
    const SpaceSummary& eden_space = ps_heap_summary->eden();
    const SpaceSummary& from_space = ps_heap_summary->from();
    const SpaceSummary& to_space = ps_heap_summary->to();

    EventPSHeapSummary e;
    if (e.should_commit()) {
      e.set_gcId(GCId::current());
      e.set_when((u1)_when);

      e.set_oldSpace(to_struct(ps_heap_summary->old()));
      e.set_oldObjectSpace(to_struct(ps_heap_summary->old_space()));
      e.set_youngSpace(to_struct(ps_heap_summary->young()));
      e.set_edenSpace(to_struct(ps_heap_summary->eden()));
      e.set_fromSpace(to_struct(ps_heap_summary->from()));
      e.set_toSpace(to_struct(ps_heap_summary->to()));
      e.commit();

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

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
when GCWhen When
oldSpace VirtualSpace struct Old Space
oldObjectSpace ObjectSpace struct Old Object Space
youngSpace VirtualSpace struct Young Space
edenSpace ObjectSpace struct Eden Space
fromSpace ObjectSpace struct From Space
toSpace ObjectSpace struct To Space

Examples 2
Example event data values and properties
edenSpace ObjectSpace
end ulong: address
33927725056
size ulong: bytes
964689920
start ulong: address
32963035136
used ulong: bytes
0
fromSpace ObjectSpace
end ulong: address
33988542464
size ulong: bytes
60817408
start ulong: address
33927725056
used ulong: bytes
0
gcId uint
380
oldObjectSpace ObjectSpace
end ulong: address
32247906304
size ulong: bytes
2080374784
start ulong: address
30167531520
used ulong: bytes
257387400
oldSpace VirtualSpace
committedEnd ulong: address
32247906304
committedSize ulong: bytes
2080374784
reservedEnd ulong: address
32963035136
reservedSize ulong: bytes
2795503616
start ulong: address
30167531520
startTime long: millis
590490082488
toSpace ObjectSpace
end ulong: address
34238103552
size ulong: bytes
58720256
start ulong: address
34179383296
used ulong: bytes
0
when GCWhen
After GC
youngSpace VirtualSpace
committedEnd ulong: address
34238103552
committedSize ulong: bytes
1275068416
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
1396703232
start ulong: address
32963035136
Example event data values and properties
edenSpace ObjectSpace
end ulong: address
33483128832
size ulong: bytes
520093696
start ulong: address
32963035136
used ulong: bytes
0
fromSpace ObjectSpace
end ulong: address
33495711744
size ulong: bytes
6291456
start ulong: address
33489420288
used ulong: bytes
0
gcId uint
24
oldObjectSpace ObjectSpace
end ulong: address
30343692288
size ulong: bytes
176160768
start ulong: address
30167531520
used ulong: bytes
6550352
oldSpace VirtualSpace
committedEnd ulong: address
30343692288
committedSize ulong: bytes
176160768
reservedEnd ulong: address
32963035136
reservedSize ulong: bytes
2795503616
start ulong: address
30167531520
startTime long: millis
1542977519
toSpace ObjectSpace
end ulong: address
33489420288
size ulong: bytes
6291456
start ulong: address
33483128832
used ulong: bytes
0
when GCWhen
After GC
youngSpace VirtualSpace
committedEnd ulong: address
33495711744
committedSize ulong: bytes
532676608
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
1396703232
start ulong: address
32963035136

G1HeapSummary

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Heap

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Code Context

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

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

    EventGCHeapSummary e;
    if (e.should_commit()) {
      e.set_gcId(GCId::current());
      e.set_when((u1)_when);
      e.set_heapSpace(to_struct(heap_space));
      e.set_heapUsed(heap_summary->used());
      e.commit();
    }
  }

  void visit(const G1HeapSummary* g1_heap_summary) const {
    visit((GCHeapSummary*)g1_heap_summary);

    EventG1HeapSummary e;
    if (e.should_commit()) {
      e.set_gcId(GCId::current());
      e.set_when((u1)_when);
      e.set_edenUsedSize(g1_heap_summary->edenUsed());
      e.set_edenTotalSize(g1_heap_summary->edenCapacity());
      e.set_survivorUsedSize(g1_heap_summary->survivorUsed());
      e.set_numberOfRegions(g1_heap_summary->numberOfRegions());
      e.commit();
    }
  }

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

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
when GCWhen When
edenUsedSize ulong: bytes Eden Used Size
edenTotalSize ulong: bytes Eden Total Size
survivorUsedSize ulong: bytes Survivor Used Size
numberOfRegions uint Number of Regions

Examples 3
Example event data values and properties
edenTotalSize ulong: bytes
399743416
edenUsedSize ulong: bytes
0
gcId uint
1084
numberOfRegions uint
442
startTime long: millis
450888694157
survivorUsedSize ulong: bytes
2909768
when GCWhen
After GC
Example event data values and properties
edenTotalSize ulong: bytes
12582912
edenUsedSize ulong: bytes
0
gcId uint
30
numberOfRegions uint
14
startTime long: millis
998963883
survivorUsedSize ulong: bytes
0
when GCWhen
After GC
Example event data values and properties
edenTotalSize ulong: bytes
515899392
edenUsedSize ulong: bytes
0
gcId uint
1023
numberOfRegions uint
410
startTime long: millis
269465802290
survivorUsedSize ulong: bytes
0
when GCWhen
After GC

JVM: GC: Metaspace

MetaspaceGCThreshold

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Metaspace

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

Missing in: graalvm_linux_native

Code Context

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

src/hotspot/share/memory/metaspaceTracer.cpp:

void MetaspaceTracer::report_gc_threshold(size_t old_val,
                                          size_t new_val,
                                          MetaspaceGCThresholdUpdater::Type updater) const {
  EventMetaspaceGCThreshold event;
  if (event.should_commit()) {
    event.set_oldValue(old_val);
    event.set_newValue(new_val);
    event.set_updater((u1)updater);
    event.commit();
  }
}

void MetaspaceTracer::report_metaspace_allocation_failure(ClassLoaderData *cld,
                                                          size_t word_size,
                                                          MetaspaceObj::Type objtype,
                                                          Metaspace::MetadataType mdtype) const {
  send_allocation_failure_event<EventMetaspaceAllocationFailure>(cld, word_size, objtype, mdtype);
}

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

Event fields with their types and descriptions
Field Type Description
oldValue ulong: bytes Old Value
newValue ulong: bytes New Value
updater GCThresholdUpdater Updater

Examples 3
Example event data values and properties
newValue ulong: bytes
1575813120
oldValue ulong: bytes
1575485440
startTime long: millis
278887823427
updater GCThresholdUpdater
compute_new_size
Example event data values and properties
newValue ulong: bytes
25165824
oldValue ulong: bytes
24707072
startTime long: millis
960785380
updater GCThresholdUpdater
compute_new_size
Example event data values and properties
newValue ulong: bytes
1598095360
oldValue ulong: bytes
1597243392
startTime long: millis
578936520780
updater GCThresholdUpdater
compute_new_size

MetaspaceAllocationFailure

profiling default startTime stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Metaspace

Code Context

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

src/hotspot/share/memory/metaspaceTracer.cpp:

  EventMetaspaceGCThreshold event;
  if (event.should_commit()) {
    event.set_oldValue(old_val);
    event.set_newValue(new_val);
    event.set_updater((u1)updater);
    event.commit();
  }
}

void MetaspaceTracer::report_metaspace_allocation_failure(ClassLoaderData *cld,
                                                          size_t word_size,
                                                          MetaspaceObj::Type objtype,
                                                          Metaspace::MetadataType mdtype) const {
  send_allocation_failure_event<EventMetaspaceAllocationFailure>(cld, word_size, objtype, mdtype);
}

void MetaspaceTracer::report_metadata_oom(ClassLoaderData *cld,
                                         size_t word_size,
                                         MetaspaceObj::Type objtype,
                                         Metaspace::MetadataType mdtype) const {
  send_allocation_failure_event<EventMetaspaceOOM>(cld, word_size, objtype, mdtype);
}

template <typename E>
void MetaspaceTracer::send_allocation_failure_event(ClassLoaderData *cld,

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

Event fields with their types and descriptions
Field Type Description
classLoader ClassLoader Class Loader
hiddenClassLoader boolean 15+ Hidden Class Loader
size ulong: bytes Size
metadataType MetadataType Metadata Type
metaspaceObjectType MetaspaceObjectType Metaspace Object Type

MetaspaceOOM

profiling default startTime stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Metaspace

Code Context

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

src/hotspot/share/memory/metaspaceTracer.cpp:

void MetaspaceTracer::report_metaspace_allocation_failure(ClassLoaderData *cld,
                                                          size_t word_size,
                                                          MetaspaceObj::Type objtype,
                                                          Metaspace::MetadataType mdtype) const {
  send_allocation_failure_event<EventMetaspaceAllocationFailure>(cld, word_size, objtype, mdtype);
}

void MetaspaceTracer::report_metadata_oom(ClassLoaderData *cld,
                                         size_t word_size,
                                         MetaspaceObj::Type objtype,
                                         Metaspace::MetadataType mdtype) const {
  send_allocation_failure_event<EventMetaspaceOOM>(cld, word_size, objtype, mdtype);
}

template <typename E>
void MetaspaceTracer::send_allocation_failure_event(ClassLoaderData *cld,
                                                    size_t word_size,
                                                    MetaspaceObj::Type objtype,
                                                    Metaspace::MetadataType mdtype) const {
  E event;
  if (event.should_commit()) {
    event.set_classLoader(cld);
    event.set_hiddenClassLoader(cld->has_class_mirror_holder());

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

Event fields with their types and descriptions
Field Type Description
classLoader ClassLoader Class Loader
hiddenClassLoader boolean 15+ Hidden Class Loader
size ulong: bytes Size
metadataType MetadataType Metadata Type
metaspaceObjectType MetaspaceObjectType Metaspace Object Type

MetaspaceChunkFreeListSummary

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Metaspace

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

Missing in: graalvm_linux_native

Code Context

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

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

void GCTracer::send_reference_stats_event(ReferenceType type, size_t count) const {
  EventGCReferenceStatistics e;
  if (e.should_commit()) {
      e.set_gcId(GCId::current());
      e.set_type((u1)type);
      e.set_count(count);
      e.commit();
  }
}

void GCTracer::send_metaspace_chunk_free_list_summary(GCWhen::Type when, Metaspace::MetadataType mdtype,
                                                      const MetaspaceChunkFreeListSummary& summary) const {
  EventMetaspaceChunkFreeListSummary e;
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_when(when);
    e.set_metadataType(mdtype);

    e.set_specializedChunks(summary.num_specialized_chunks());
    e.set_specializedChunksTotalSize(summary.specialized_chunks_size_in_bytes());

    e.set_smallChunks(summary.num_small_chunks());
    e.set_smallChunksTotalSize(summary.small_chunks_size_in_bytes());

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

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
when GCWhen When
metadataType MetadataType Metadata Type
specializedChunks ulong Specialized Chunks
specializedChunksTotalSize ulong: bytes Specialized Chunks Total Size
smallChunks ulong Small Chunks
smallChunksTotalSize ulong: bytes Small Chunks Total Size
mediumChunks ulong Medium Chunks
mediumChunksTotalSize ulong: bytes Medium Chunks Total Size
humongousChunks ulong Humongous Chunks
humongousChunksTotalSize ulong: bytes Humongous Chunks Total Size

Examples 3
Example event data values and properties
gcId uint
21
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
867038447
when GCWhen
Before GC
Example event data values and properties
gcId uint
1016
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
268095369837
when GCWhen
After GC
Example event data values and properties
gcId uint
353
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
547244784659
when GCWhen
Before GC

JVM: GC: Phases

GCPhasePause

profiling default startTime duration eventThread graal vm only

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");

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

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

Examples 3
Example event data values and properties
gcId uint
357
name string
GC Pause
startTime long: millis
554608374569
Example event data values and properties
gcId uint
66
name string
GC Pause
startTime long: millis
1347122713
Example event data values and properties
gcId uint
1026
name string
GC Pause
startTime long: millis
269597494643

GCPhasePauseLevel1

profiling default startTime duration eventThread graal vm only

Category: Java Virtual Machine / GC / Phases

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

Missing in: linux_ZGC

Code Context

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

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

    e.set_metaspace(to_struct(meta_space_summary.stats())); // total stats (class + nonclass)
    e.set_dataSpace(to_struct(meta_space_summary.stats().non_class_space_stats())); // "dataspace" aka non-class space
    e.set_classSpace(to_struct(meta_space_summary.stats().class_space_stats()));
    e.commit();
  }
}

class PhaseSender : public PhaseVisitor {
  void visit_pause(GCPhase* phase) {
    assert(phase->level() < PhasesStack::PHASE_LEVELS, "Need more event types for PausePhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhasePause>(phase); break;
      case 1: send_phase<EventGCPhasePauseLevel1>(phase); break;
      case 2: send_phase<EventGCPhasePauseLevel2>(phase); break;
      case 3: send_phase<EventGCPhasePauseLevel3>(phase); break;
      case 4: send_phase<EventGCPhasePauseLevel4>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 2, "There is only two levels for ConcurrentPhase");

    switch (phase->level()) {

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

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

Examples 3
Example event data values and properties
gcId uint
8
name string
Notify Soft/WeakReferences
startTime long: millis
426581312
Example event data values and properties
gcId uint
354
name string
Pre Compact
startTime long: millis
549142293991
Example event data values and properties
gcId uint
1034
name string
Report Object Count
startTime long: millis
271190439355

GCPhasePauseLevel2

profiling default startTime duration eventThread graal vm only

Category: Java Virtual Machine / GC / Phases

Appearing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: linux_ShenandoahGC, linux_ZGC

Code Context

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

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

    e.set_dataSpace(to_struct(meta_space_summary.stats().non_class_space_stats())); // "dataspace" aka non-class space
    e.set_classSpace(to_struct(meta_space_summary.stats().class_space_stats()));
    e.commit();
  }
}

class PhaseSender : public PhaseVisitor {
  void visit_pause(GCPhase* phase) {
    assert(phase->level() < PhasesStack::PHASE_LEVELS, "Need more event types for PausePhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhasePause>(phase); break;
      case 1: send_phase<EventGCPhasePauseLevel1>(phase); break;
      case 2: send_phase<EventGCPhasePauseLevel2>(phase); break;
      case 3: send_phase<EventGCPhasePauseLevel3>(phase); break;
      case 4: send_phase<EventGCPhasePauseLevel4>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 2, "There is only two levels for ConcurrentPhase");

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

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

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

Examples 3
Example event data values and properties
gcId uint
32
name string
Report Object Count
startTime long: millis
1012001325
Example event data values and properties
gcId uint
1041
name string
Phase 2: Prepare parallel compaction
startTime long: millis
272019478712
Example event data values and properties
gcId uint
357
name string
Drain Task Setup
startTime long: millis
554921686931

GCPhasePauseLevel3

startTime duration eventThread graal vm only

Category: Java Virtual Machine / GC / Phases

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

Code Context

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

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

    e.set_classSpace(to_struct(meta_space_summary.stats().class_space_stats()));
    e.commit();
  }
}

class PhaseSender : public PhaseVisitor {
  void visit_pause(GCPhase* phase) {
    assert(phase->level() < PhasesStack::PHASE_LEVELS, "Need more event types for PausePhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhasePause>(phase); break;
      case 1: send_phase<EventGCPhasePauseLevel1>(phase); break;
      case 2: send_phase<EventGCPhasePauseLevel2>(phase); break;
      case 3: send_phase<EventGCPhasePauseLevel3>(phase); break;
      case 4: send_phase<EventGCPhasePauseLevel4>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 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;

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

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

Examples 3
Example event data values and properties
gcId uint
1029
name string
Unregister NMethods
startTime long: millis
270443412691
Example event data values and properties
gcId uint
352
name string
Notify and keep alive finalizable
startTime long: millis
545676477788
Example event data values and properties
gcId uint
29
name string
Unregister NMethods
startTime long: millis
982070322

GCPhasePauseLevel4

startTime duration eventThread graal vm only

Category: Java Virtual Machine / GC / Phases

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC

Missing in: graalvm_linux_native, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Code Context

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

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

    e.commit();
  }
}

class PhaseSender : public PhaseVisitor {
  void visit_pause(GCPhase* phase) {
    assert(phase->level() < PhasesStack::PHASE_LEVELS, "Need more event types for PausePhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhasePause>(phase); break;
      case 1: send_phase<EventGCPhasePauseLevel1>(phase); break;
      case 2: send_phase<EventGCPhasePauseLevel2>(phase); break;
      case 3: send_phase<EventGCPhasePauseLevel3>(phase); break;
      case 4: send_phase<EventGCPhasePauseLevel4>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 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;

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

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

Examples 3
Example event data values and properties
gcId uint
389
name string
Balance queues
startTime long: millis
609020289944
Example event data values and properties
gcId uint
1168
name string
Balance queues
startTime long: millis
476450742508
Example event data values and properties
gcId uint
1080
name string
Balance queues
startTime long: millis
277796389541

GCPhaseConcurrent

profiling default startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC

Code Context

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

src/hotspot/share/gc/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());

src/hotspot/share/gc/shenandoah/shenandoahUtils.hpp:

  ShenandoahWorkerSession(uint worker_id);
  ~ShenandoahWorkerSession();
public:
  static inline uint worker_id() {
    Thread* thr = Thread::current();
    uint id = ShenandoahThreadLocalData::worker_id(thr);
    assert(id != ShenandoahThreadLocalData::INVALID_WORKER_ID, "Worker session has not been created");
    return 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:

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

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

Examples 3
Example event data values and properties
gcId uint
290
name string
Concurrent weak roots (unload classes)
startTime long: millis
575823334438
Example event data values and properties
gcId uint
1040
name string
Concurrent Scan Root Regions
startTime long: millis
271705717177
Example event data values and properties
gcId uint
683
name string
Concurrent Mark From Roots
startTime long: millis
6560680122

GCPhaseConcurrentLevel1

profiling default startTime duration eventThread 15 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC

Code Context

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

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

      case 1: send_phase<EventGCPhasePauseLevel1>(phase); break;
      case 2: send_phase<EventGCPhasePauseLevel2>(phase); break;
      case 3: send_phase<EventGCPhasePauseLevel3>(phase); break;
      case 4: send_phase<EventGCPhasePauseLevel4>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 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());

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

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

Examples 3
Example event data values and properties
gcId uint
315
name string
Trigger cleanups
startTime long: millis
616449089675
Example event data values and properties
gcId uint
2358
name string
Preclean SoftReferences
startTime long: millis
21429445759
Example event data values and properties
gcId uint
1092
name string
Preclean SoftReferences
startTime long: millis
279617836781

GCPhaseParallel

profiling default startTime duration eventThread 12 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ShenandoahGC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC, linux_ZGC

GC phases for parallel workers

Code Context

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

src/hotspot/share/gc/g1/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/g1CollectedHeap.cpp:

    // itself is released in SuspendibleThreadSet::desynchronize().
    start_concurrent_cycle(concurrent_operation_is_full_mark);
    ConcurrentGCBreakpoints::notify_idle_to_active();
  }
}

void G1CollectedHeap::preserve_mark_during_evac_failure(uint worker_id, oop obj, markWord m) {
  _evacuation_failed_info_array[worker_id].register_copy_failure(obj->size());
  _preserved_marks_set.get(worker_id)->push_if_necessary(obj, m);
}

bool G1ParEvacuateFollowersClosure::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;
}

void G1ParEvacuateFollowersClosure::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());
}

void G1CollectedHeap::complete_cleaning(BoolObjectClosure* is_alive,
                                        bool class_unloading_occurred) {
  uint num_workers = workers()->active_workers();
  G1ParallelCleaningTask unlink_task(is_alive, num_workers, class_unloading_occurred);
  workers()->run_task(&unlink_task);

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/g1RemSet.cpp:

    _scanned_to = scan_memregion(region_idx_for_card, mr);

    _cards_scanned += num_cards;
  }

  ALWAYSINLINE void do_card_block(uint const region_idx, size_t const first_card, size_t const num_cards) {
    _ct->change_dirty_cards_to(first_card, num_cards, _scanned_card_value);
    do_claimed_block(region_idx, first_card, num_cards);
    _blocks_scanned++;
  }

   void scan_heap_roots(HeapRegion* r) {
    EventGCPhaseParallel event;
    uint const region_idx = r->hrm_index();

    ResourceMark rm;

    G1CardTableChunkClaimer claim(_scan_state, region_idx);

    // Set the current scan "finger" to NULL for every heap region to scan. Since
    // the claim value is monotonically increasing, the check to not scan below this
    // will filter out objects spanning chunks within the region too then, as opposed
    // to resetting this value for every claim.

src/hotspot/share/gc/g1/g1RemSet.cpp:

  uint _worker_id;

  size_t _opt_refs_scanned;
  size_t _opt_refs_memory_used;

  Tickspan _strong_code_root_scan_time;
  Tickspan _strong_code_trim_partially_time;

  Tickspan _rem_set_opt_root_scan_time;
  Tickspan _rem_set_opt_trim_partially_time;

  void scan_opt_rem_set_roots(HeapRegion* r) {
    EventGCPhaseParallel event;

    G1OopStarChunkedList* opt_rem_set_list = _pss->oops_into_optional_region(r);

    G1ScanCardClosure scan_cl(G1CollectedHeap::heap(), _pss);
    G1ScanRSForOptionalClosure cl(G1CollectedHeap::heap(), &scan_cl);
    _opt_refs_scanned += opt_rem_set_list->oops_do(&cl, _pss->closures()->strong_oops());
    _opt_refs_memory_used += opt_rem_set_list->used_memory();

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

src/hotspot/share/gc/g1/g1RemSet.cpp:

  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()) {
      G1EvacPhaseWithTrimTimeTracker timer(_pss, _rem_set_opt_root_scan_time, _rem_set_opt_trim_partially_time);
      scan_opt_rem_set_roots(r);
    }

    if (_scan_state->claim_collection_set_region(region_idx)) {
      EventGCPhaseParallel event;

      G1EvacPhaseWithTrimTimeTracker timer(_pss, _strong_code_root_scan_time, _strong_code_trim_partially_time);
      // Scan the strong code root list attached to the current region
      r->strong_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/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 _must_record;

public:
  G1GCParPhaseTimesTracker(G1GCPhaseTimes* phase_times, G1GCPhaseTimes::GCParPhases phase, uint worker_id, bool must_record = true);
  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

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) {

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

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
gcWorkerId uint GC Worker Identifier
name string Name

Examples 3
Example event data values and properties
gcId uint
319
gcWorkerId uint
1
name string
Finish Mark
startTime long: millis
618028822778
Example event data values and properties
gcId uint
4
gcWorkerId uint
2
name string
JVMTI OopStorage
startTime long: millis
381494686
Example event data values and properties
gcId uint
1010
gcWorkerId uint
2
name string
JVMTI OopStorage
startTime long: millis
267887539793

JVM: GC: Reference

GCReferenceStatistics

profiling default startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Reference

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

Missing in: graalvm_linux_native

Total count of processed references during GC

Code Context

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

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

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

void GCTracer::send_reference_stats_event(ReferenceType type, size_t count) const {
  EventGCReferenceStatistics e;
  if (e.should_commit()) {
      e.set_gcId(GCId::current());
      e.set_type((u1)type);
      e.set_count(count);
      e.commit();
  }
}

void GCTracer::send_metaspace_chunk_free_list_summary(GCWhen::Type when, Metaspace::MetadataType mdtype,
                                                      const MetaspaceChunkFreeListSummary& summary) const {
  EventMetaspaceChunkFreeListSummary e;

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

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
type ReferenceType Type
count ulong Total Count

Examples 3
Example event data values and properties
count ulong
0
gcId uint
18
startTime long: millis
779186021
type ReferenceType
Phantom reference
Example event data values and properties
count ulong
0
gcId uint
370
startTime long: millis
580147530579
type ReferenceType
Soft reference
Example event data values and properties
count ulong
316
gcId uint
1032
startTime long: millis
270821855184
type ReferenceType
Final reference

JVM: Profiling

OldObjectSample

cutoff profiling default startTime eventThread stackTrace 11 17 21 25 27 28 graal vm

Category: Java Virtual Machine / Profiling

Appearing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: linux_ShenandoahGC, linux_ZGC

A potential memory leak

Code Context

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

src/hotspot/share/jfr/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/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_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
  // onto the thread local data structure of the emitter thread (for the duration

src/hotspot/share/jfr/leakprofiler/sampling/objectSampler.cpp:

  if (!tl->has_thread_blob()) {
    JfrCheckpointManager::create_thread_blob(thread);
  }
  assert(tl->has_thread_blob(), "invariant");
  return tl->thread_id();
}

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();
    }
  }
};

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

Event fields with their types and descriptions
Field Type Description
allocationTime Ticks Allocation Time
objectAge Tickspan 14+ Object Age
lastKnownHeapUsage ulong: bytes Last Known Heap Usage
object OldObject Object
arrayElements int Array Elements If the object is an array, the number of elements, or minimum value for the type int if it is not an array
root OldObjectGcRoot GC Root

Examples 3
Example event data values and properties
allocationTime Ticks
20832544279
arrayElements int
-2147483648
lastKnownHeapUsage ulong: bytes
30412800
object OldObject
address ulong: address
30198658240
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/ConcurrentHashMap$Node
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent
objectAge Tickspan
588098602680
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
83
lineNumber int
1031
method Method
descriptor string
(Ljava/lang/Object;Ljava/lang/Object;Z)Ljava/lang/Object;
hidden boolean
false
modifiers int
16
name string
putVal
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/ConcurrentHashMap
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
608931146959
Example event data values and properties
allocationTime Ticks
25246409681
arrayElements int
4096
lastKnownHeapUsage ulong: bytes
7396280
object OldObject
address ulong: address
30172949880
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
objectAge Tickspan
17356929
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
24
lineNumber int
494
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
allocateAndGC
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
25263766610
Example event data values and properties
allocationTime Ticks
295330495168
arrayElements int
-2147483648
lastKnownHeapUsage ulong: bytes
261565808
object OldObject
address ulong: address
30371924960
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Class
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
objectAge Tickspan
5706898803
root OldObjectGcRoot
null
stackTrace StackTrace
null
startTime long: millis
301037393971

ExecutionSample

profiling default startTime every chunk graal vm only

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/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

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 os::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(jth)) {
    return;
  }
  JfrGetCallTrace trace(true, jth);
  frame topframe;
  if (trace.get_topframe(context.ucontext(), topframe)) {
    if (_stacktrace.record_thread(*jth, 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(JFR_THREAD_ID(jth));
      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:

bool JfrThreadSampleClosure::sample_thread_in_java(JavaThread* thread, JfrStackFrame* frames, u4 max_frames) {
  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) {
  JfrNativeSamplerCallback cb(*this, thread, frames, max_frames);
  if (JfrOptionSet::sample_protection()) {
    os::ThreadCrashProtection crash_protection;
    if (!crash_protection.call(cb)) {

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:

      last_native_ms = get_monotonic_ms();
    }
  }
}

void JfrThreadSampler::post_run() {
  this->NonJavaThread::post_run();
  delete this;
}


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();
    {

Event configuration settings across JFR profiles
Configuration enabled period
profiling true 10 ms
default true 20 ms

Event fields with their types and descriptions
Field Type Description
sampledThread Thread Thread
stackTrace StackTrace Stack Trace
state ThreadState Thread State

Examples 3
Example event data values and properties
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
4621
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
30
lineNumber int
484
method Method
descriptor string
(Ljava/nio/ByteBuffer;Z)V
hidden boolean
false
modifiers int
8
name string
acquireScope
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
sun/nio/ch/IOUtil
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
sun/nio/ch
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
970922628
state ThreadState
STATE_RUNNABLE
Example event data values and properties
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 3.0 in stage 48.0 (TID 189)
javaThreadId long
1678
osName string
Executor task launch worker for task 3.0 in stage 48.0 (TID 189)
osThreadId long
4208
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
201
method Method
descriptor string
([D[Lorg/apache/spark/mllib/stat/distribution/MultivariateGaussian;Lorg/apache/spark/mllib/clustering/ExpectationSum;Lbreeze/linalg/Vector;)Lorg/apache/spark/mllib/clustering/ExpectationSum;
hidden boolean
false
modifiers int
4121
name string
$anonfun$run$5
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/mllib/clustering/GaussianMixture
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/mllib/clustering
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
269717142043
state ThreadState
STATE_RUNNABLE
Example event data values and properties
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 0.0 in stage 33.0 (TID 126)
javaThreadId long
1735
osName string
Executor task launch worker for task 0.0 in stage 33.0 (TID 126)
osThreadId long
4632
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
274
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/String;ID[DII[DII)V
hidden boolean
false
modifiers int
9
name string
dsyr
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
org/netlib/blas/Dsyr
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/netlib/blas
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
541986298035
state ThreadState
STATE_RUNNABLE

NativeMethodSample

profiling default startTime every chunk 11 17 21 25 27 28 graal vm

Category: Java Virtual Machine / Profiling

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

Missing in: graalvm_linux_native

Snapshot of a threads state 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/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

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

bool JfrThreadSampleClosure::sample_thread_in_native(JavaThread* thread, JfrStackFrame* frames, u4 max_frames) {
  JfrNativeSamplerCallback cb(*this, thread, frames, max_frames);
  if (JfrOptionSet::sample_protection()) {
    os::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:

void JfrThreadSampler::post_run() {
  this->NonJavaThread::post_run();
  delete this;
}


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);

Event configuration settings across JFR profiles
Configuration enabled period
profiling true 20 ms
default true 20 ms

Event fields with their types and descriptions
Field Type Description
sampledThread Thread Thread
stackTrace StackTrace Stack Trace
state ThreadState Thread State

Examples 3
Example event data values and properties
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
4621
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/io/FileDescriptor;IJ)I
hidden boolean
false
modifiers int
264
name string
poll
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/nio/ch/Net
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
sun/nio/ch
type FrameType
Native
…
truncated boolean
false
startTime long: millis
734039706
state ThreadState
STATE_RUNNABLE
Example event data values and properties
sampledThread Thread
group ThreadGroup
name string
finagle/netty4
parent ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
finagle/netty4-2-1
javaThreadId long
890
osName string
finagle/netty4-2-1
osThreadId long
3319
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(IJII)I
hidden boolean
false
modifiers int
266
name string
epollWait
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
io/netty/channel/epoll/Native
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/channel/epoll
type FrameType
Native
…
truncated boolean
false
startTime long: millis
269239753793
state ThreadState
STATE_RUNNABLE
Example event data values and properties
sampledThread Thread
group ThreadGroup
name string
finagle/netty4
parent ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
finagle/netty4-2-6
javaThreadId long
931
osName string
finagle/netty4-2-6
osThreadId long
3736
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(IJII)I
hidden boolean
false
modifiers int
266
name string
epollWait
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
io/netty/channel/epoll/Native
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/channel/epoll
type FrameType
Native
…
truncated boolean
false
startTime long: millis
540726470077
state ThreadState
STATE_RUNNABLE

JVM: Runtime

BiasedLockRevocation

profiling default startTime duration eventThread stackTrace 11 17 until JDK 18

Category: Java Virtual Machine / Runtime

Revoked bias of object

Code Context

The event is likely defined and utilized 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/biasedLocking.cpp:

static void post_self_revocation_event(EventBiasedLockSelfRevocation* event, Klass* k) {
  assert(event != NULL, "invariant");
  assert(k != NULL, "invariant");
  assert(event->should_commit(), "invariant");
  event->set_lockClass(k);
  event->commit();
}

static void post_revocation_event(EventBiasedLockRevocation* event, Klass* k, RevokeOneBias* op) {
  assert(event != NULL, "invariant");
  assert(k != NULL, "invariant");
  assert(op != NULL, "invariant");
  assert(event->should_commit(), "invariant");
  event->set_lockClass(k);
  event->set_safepointId(0);
  event->set_previousOwner(op->biased_locker());
  event->commit();
}

static void post_class_revocation_event(EventBiasedLockClassRevocation* event, Klass* k, VM_BulkRevokeBias* op) {

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

  assert(event != NULL, "invariant");
  assert(k != NULL, "invariant");
  assert(op != NULL, "invariant");
  assert(event->should_commit(), "invariant");
  event->set_revokedClass(k);
  event->set_disableBiasing(!op->is_bulk_rebias());
  event->set_safepointId(op->safepoint_id());
  event->commit();
}


BiasedLocking::Condition BiasedLocking::single_revoke_with_handshake(Handle obj, JavaThread *requester, JavaThread *biaser) {

  EventBiasedLockRevocation event;
  if (PrintBiasedLockingStatistics) {
    Atomic::inc(handshakes_count_addr());
  }
  log_info(biasedlocking, handshake)("JavaThread " INTPTR_FORMAT " handshaking JavaThread "
                                     INTPTR_FORMAT " to revoke object " INTPTR_FORMAT, p2i(requester),
                                     p2i(biaser), p2i(obj()));

  RevokeOneBias revoke(obj, requester, biaser);
  Handshake::execute(&revoke, biaser);
  if (revoke.status_code() == NOT_REVOKED) {
    return NOT_REVOKED;

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

Event fields with their types and descriptions
Field Type Description
lockClass Class Lock Class Class of object whose biased lock was revoked
safepointId ulong Safepoint Identifier
previousOwner Thread Previous Owner Thread owning the bias before revocation

BiasedLockSelfRevocation

profiling default startTime duration eventThread stackTrace 11 17 until JDK 18

Category: Java Virtual Machine / Runtime

Revoked bias of object biased towards own thread

Code Context

The event is likely defined and utilized 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/biasedLocking.cpp:

    _status_code = BiasedLocking::NOT_REVOKED;
  }

  BiasedLocking::Condition status_code() const {
    return _status_code;
  }

  traceid biased_locker() const {
    return _biased_locker_id;
  }
};


static void post_self_revocation_event(EventBiasedLockSelfRevocation* event, Klass* k) {
  assert(event != NULL, "invariant");
  assert(k != NULL, "invariant");
  assert(event->should_commit(), "invariant");
  event->set_lockClass(k);
  event->commit();
}

static void post_revocation_event(EventBiasedLockRevocation* event, Klass* k, RevokeOneBias* op) {
  assert(event != NULL, "invariant");
  assert(k != NULL, "invariant");
  assert(op != NULL, "invariant");

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

void BiasedLocking::revoke_own_lock(JavaThread* current, Handle obj) {
  markWord mark = obj->mark();

  if (!mark.has_bias_pattern()) {
    return;
  }

  Klass *k = obj->klass();
  assert(mark.biased_locker() == current &&
         k->prototype_header().bias_epoch() == mark.bias_epoch(), "Revoke failed, unhandled biased lock state");
  ResourceMark rm(current);
  log_info(biasedlocking)("Revoking bias by walking my own stack:");
  EventBiasedLockSelfRevocation event;
  BiasedLocking::walk_stack_and_revoke(obj(), current);
  current->set_cached_monitor_info(NULL);
  assert(!obj->mark().has_bias_pattern(), "invariant");
  if (event.should_commit()) {
    post_self_revocation_event(&event, k);
  }
}

void BiasedLocking::revoke(JavaThread* current, Handle obj) {
  assert(!SafepointSynchronize::is_at_safepoint(), "must not be called while at safepoint");

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

    HeuristicsResult heuristics = update_heuristics(obj());
    if (heuristics == HR_NOT_BIASED) {
      return;
    } else if (heuristics == HR_SINGLE_REVOKE) {
      JavaThread *blt = mark.biased_locker();
      assert(blt != NULL, "invariant");
      if (blt == current) {
        // A thread is trying to revoke the bias of an object biased
        // toward it, again likely due to an identity hash code
        // computation. We can again avoid a safepoint/handshake in this case
        // since we are only going to walk our own stack. There are no
        // races with revocations occurring in other threads because we
        // reach no safepoints in the revocation path.
        EventBiasedLockSelfRevocation event;
        ResourceMark rm(current);
        walk_stack_and_revoke(obj(), blt);
        blt->set_cached_monitor_info(NULL);
        assert(!obj->mark().has_bias_pattern(), "invariant");
        if (event.should_commit()) {
          post_self_revocation_event(&event, obj->klass());
        }
        return;
      } else {
        BiasedLocking::Condition cond = single_revoke_with_handshake(obj, current, blt);
        if (cond != NOT_REVOKED) {

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

Event fields with their types and descriptions
Field Type Description
lockClass Class Lock Class Class of object whose biased lock was revoked

BiasedLockClassRevocation

profiling default startTime duration eventThread stackTrace 11 17 until JDK 18

Category: Java Virtual Machine / Runtime

Revoked biases for all instances of a class

Code Context

The event is likely defined and utilized 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/biasedLocking.cpp:

static void post_revocation_event(EventBiasedLockRevocation* event, Klass* k, RevokeOneBias* op) {
  assert(event != NULL, "invariant");
  assert(k != NULL, "invariant");
  assert(op != NULL, "invariant");
  assert(event->should_commit(), "invariant");
  event->set_lockClass(k);
  event->set_safepointId(0);
  event->set_previousOwner(op->biased_locker());
  event->commit();
}

static void post_class_revocation_event(EventBiasedLockClassRevocation* event, Klass* k, VM_BulkRevokeBias* op) {
  assert(event != NULL, "invariant");
  assert(k != NULL, "invariant");
  assert(op != NULL, "invariant");
  assert(event->should_commit(), "invariant");
  event->set_revokedClass(k);
  event->set_disableBiasing(!op->is_bulk_rebias());
  event->set_safepointId(op->safepoint_id());
  event->commit();
}

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

        if (event.should_commit()) {
          post_self_revocation_event(&event, obj->klass());
        }
        return;
      } else {
        BiasedLocking::Condition cond = single_revoke_with_handshake(obj, current, blt);
        if (cond != NOT_REVOKED) {
          return;
        }
      }
    } else {
      assert((heuristics == HR_BULK_REVOKE) ||
         (heuristics == HR_BULK_REBIAS), "?");
      EventBiasedLockClassRevocation event;
      VM_BulkRevokeBias bulk_revoke(&obj, current, (heuristics == HR_BULK_REBIAS));
      VMThread::execute(&bulk_revoke);
      if (event.should_commit()) {
        post_class_revocation_event(&event, obj->klass(), &bulk_revoke);
      }
      return;
    }
  }
}

// All objects in objs should be locked by biaser

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

Event fields with their types and descriptions
Field Type Description
revokedClass Class Revoked Class Class whose biased locks were revoked
disableBiasing boolean Disable Further Biasing Whether further biasing for instances of this class will be allowed
safepointId ulong Safepoint Identifier

ReservedStackActivation

profiling default startTime eventThread stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime

Activation of Reserved Stack Area caused by stack overflow with ReservedStackAccess annotated method in call stack

Code Context

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

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

        for (ScopeDesc *sd = nm->scope_desc_near(fr.pc()); sd != 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();
      }
    }
    if (fr.is_first_java_frame()) {
      break;
    } else {
      fr = fr.java_sender();
    }
  }

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

Event fields with their types and descriptions
Field Type Description
method Method Java Method

SafepointBegin

profiling default startTime duration eventThread graal vm only

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:

  OrderAccess::storestore(); // storestore, global state -> local state
  for (JavaThreadIteratorWithHandle jtiwh; JavaThread *cur = jtiwh.next(); ) {
    // Make sure the threads start polling, it is time to yield.
    SafepointMechanism::arm_local_poll(cur);
  }

  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();

Event configuration settings across JFR profiles
Configuration enabled threshold
profiling true 0 ms
default true 10 ms

Event fields with their types and descriptions
Field Type Description
safepointId ulong Safepoint Identifier
totalThreadCount int Total Threads The total number of threads at the start of safe point
jniCriticalThreadCount int JNI Critical Threads The number of threads in JNI critical sections

Examples 3
Example event data values and properties
jniCriticalThreadCount int
0
safepointId ulong
1497
startTime long: millis
270917838189
totalThreadCount int
301
Example event data values and properties
jniCriticalThreadCount int
0
safepointId ulong
531
startTime long: millis
549140833976
totalThreadCount int
300
Example event data values and properties
jniCriticalThreadCount int
0
safepointId ulong
98
startTime long: millis
1516327003
totalThreadCount int
25

SafepointStateSynchronization

startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime / Safepoint

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

Missing in: graalvm_linux_native

Synchronize run state of threads

Code Context

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

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

    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

Event configuration settings across JFR profiles
Configuration enabled threshold
profiling false 0 ms
default false 10 ms

Event fields with their types and descriptions
Field Type Description
safepointId ulong Safepoint Identifier
initialThreadCount int Initial Threads The number of threads running at the beginning of state check
runningThreadCount int Running Threads The number of threads still running
iterations int Iterations Number of state check iterations

Examples 3
Example event data values and properties
initialThreadCount int
1
iterations int
3
runningThreadCount int
0
safepointId ulong
529
startTime long: millis
547244613177
Example event data values and properties
initialThreadCount int
0
iterations int
1
runningThreadCount int
0
safepointId ulong
89
startTime long: millis
1450393487
Example event data values and properties
initialThreadCount int
1
iterations int
36
runningThreadCount int
0
safepointId ulong
1540
startTime long: millis
275436896588

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;

Event configuration settings across JFR profiles
Configuration enabled threshold
profiling false 0 ms
default false 10 ms

Event fields with their types and descriptions
Field Type Description
safepointId ulong Safepoint Identifier

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 AbstractGangTask {
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);
    }
  };

Event configuration settings across JFR profiles
Configuration enabled threshold
profiling false 0 ms
default false 10 ms

Event fields with their types and descriptions
Field Type Description
safepointId ulong Safepoint Identifier
name string Task Name The task name

SafepointEnd

startTime duration eventThread graal vm only

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());
}

Event configuration settings across JFR profiles
Configuration enabled threshold
profiling false 0 ms
default false 10 ms

Event fields with their types and descriptions
Field Type Description
safepointId ulong Safepoint Identifier

Examples 3
Example event data values and properties
safepointId ulong
590
startTime long: millis
602010908187
Example event data values and properties
safepointId ulong
1495
startTime long: millis
270910655693
Example event data values and properties
safepointId ulong
30
startTime long: millis
867752705

ExecuteVMOperation

profiling default startTime duration eventThread graal vm only

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);
  }

}

Event configuration settings across JFR profiles
Configuration enabled threshold
profiling true 0 ms
default true 10 ms

Event fields with their types and descriptions
Field Type Description
operation VMOperationType Operation
safepoint boolean At Safepoint If the operation occured at a safepoint
blocking boolean Caller Blocked If the calling thread was blocked until the operation was complete
caller Thread Caller Thread requesting operation. If non-blocking, will be set to 0 indicating thread is unknown
safepointId ulong Safepoint Identifier The safepoint (if any) under which this operation was completed

Examples 3
Example event data values and properties
blocking boolean
true
caller Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
2435
virtual boolean
false
operation VMOperationType
HandshakeAllThreads
safepoint boolean
false
safepointId ulong
0
startTime long: millis
598210372496
Example event data values and properties
blocking boolean
true
caller Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
JFR Periodic Tasks
javaThreadId long
23
osName string
JFR Periodic Tasks
osThreadId long
2200
virtual boolean
false
operation VMOperationType
HeapIterateOperation
safepoint boolean
true
safepointId ulong
1563
startTime long: millis
277886257692
Example event data values and properties
blocking boolean
true
caller Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
4621
virtual boolean
false
operation VMOperationType
FindDeadlocks
safepoint boolean
true
safepointId ulong
33
startTime long: millis
875105033

Shutdown

profiling default startTime eventThread stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime

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

Missing in: graalvm_linux_native

JVM shutting down

Code Context

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

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

// 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 (DynamicDumpSharedSpaces) {
    DynamicArchive::prepare_for_dynamic_dumping_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/runtime/thread.cpp:

  JavaThread* thread = JavaThread::current();

#ifdef ASSERT
  _vm_complete = false;
#endif
  // Wait until we are the last non-daemon thread to execute
  {
    MonitorLocker nu(Threads_lock);
    while (Threads::number_of_non_daemon_threads() > 1)
      // This wait should make safepoint checks, wait without a timeout.
      nu.wait(0);
  }

  EventShutdown e;
  if (e.should_commit()) {
    e.set_reason("No remaining non-daemon Java threads");
    e.commit();
  }

  // Hang forever on exit if we are reporting an error.
  if (ShowMessageBoxOnError && VMError::is_error_reported()) {
    os::infinite_sleep();
  }
  os::wait_for_keypress_at_exit();

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

  void transition_to_native() {
    if (_jt != 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();
}

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

Event fields with their types and descriptions
Field Type Description
reason string Reason Reason for JVM shutdown

Examples 3
Example event data values and properties
reason string
No remaining non-daemon Java threads
stackTrace StackTrace
null
startTime long: millis
25263384779
Example event data values and properties
reason string
No remaining non-daemon Java threads
stackTrace StackTrace
null
startTime long: millis
301036904577
Example event data values and properties
reason string
No remaining non-daemon Java threads
stackTrace StackTrace
null
startTime long: millis
608930209787

SymbolTableStatistics

profiling startTime duration every chunk 13 17 21 25 27 28

Category: Java Virtual Machine / Runtime / Tables

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

Missing in: graalvm_linux_native

Code Context

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

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

  event.set_entryCount(statistics._number_of_entries);
  event.set_totalFootprint(statistics._total_footprint);
  event.set_bucketCountMaximum(statistics._maximum_bucket_size);
  event.set_bucketCountAverage(statistics._average_bucket_size);
  event.set_bucketCountVariance(statistics._variance_of_bucket_size);
  event.set_bucketCountStandardDeviation(statistics._stddev_of_bucket_size);
  event.set_insertionRate(statistics._add_rate);
  event.set_removalRate(statistics._remove_rate);
  event.commit();
}

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

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

TRACE_REQUEST_FUNC(PlaceholderTableStatistics) {
  TableStatistics statistics = SystemDictionary::placeholders_statistics();
  emit_table_statistics<EventPlaceholderTableStatistics>(statistics);
}

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

Event fields with their types and descriptions
Field Type Description
bucketCount ulong Bucket Count Number of buckets
entryCount ulong Entry Count Number of all entries
totalFootprint ulong: bytes Total Footprint Total memory footprint (the table itself plus all of the entries)
bucketCountMaximum ulong Maximum Bucket Count The maximum bucket length (entries in a single bucket)
bucketCountAverage float Average Bucket Count The average bucket length
bucketCountVariance float Bucket Count Variance How far bucket lengths are spread out from their average value
bucketCountStandardDeviation float Bucket Count Standard Deviation How far bucket lengths are spread out from their mean (expected) value
insertionRate float Insertion Rate How many items were added since last event (per second)
removalRate float Removal Rate How many items were removed since last event (per second)

Examples 3
Example event data values and properties
bucketCount ulong
0
bucketCountAverage float
0.0
bucketCountMaximum ulong
0
bucketCountStandardDeviation float
0.0
bucketCountVariance float
0.0
entryCount ulong
0
insertionRate float
0.0
removalRate float
0.0
startTime long: millis
10431631039
totalFootprint ulong: bytes
0
Example event data values and properties
bucketCount ulong
131072
bucketCountAverage float
4.8569107
bucketCountMaximum ulong
17
bucketCountStandardDeviation float
2.2080808
bucketCountVariance float
4.875621
entryCount ulong
636605
insertionRate float
12.619106
removalRate float
5.9531994
startTime long: millis
560834218752
totalFootprint ulong: bytes
70768968
Example event data values and properties
bucketCount ulong
131072
bucketCountAverage float
4.802841
bucketCountMaximum ulong
18
bucketCountStandardDeviation float
2.1938856
bucketCountVariance float
4.8131332
entryCount ulong
629518
insertionRate float
128.529
removalRate float
13.306533
startTime long: millis
275226833816
totalFootprint ulong: bytes
70281864

StringTableStatistics

profiling startTime duration every chunk 13 17 21 25 27 28

Category: Java Virtual Machine / Runtime / Tables

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

Missing in: graalvm_linux_native

Code Context

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

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

  event.set_bucketCountStandardDeviation(statistics._stddev_of_bucket_size);
  event.set_insertionRate(statistics._add_rate);
  event.set_removalRate(statistics._remove_rate);
  event.commit();
}

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

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

TRACE_REQUEST_FUNC(PlaceholderTableStatistics) {
  TableStatistics statistics = SystemDictionary::placeholders_statistics();
  emit_table_statistics<EventPlaceholderTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(LoaderConstraintsTableStatistics) {
  TableStatistics statistics = SystemDictionary::loader_constraints_statistics();
  emit_table_statistics<EventLoaderConstraintsTableStatistics>(statistics);
}

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

Event fields with their types and descriptions
Field Type Description
bucketCount ulong Bucket Count Number of buckets
entryCount ulong Entry Count Number of all entries
totalFootprint ulong: bytes Total Footprint Total memory footprint (the table itself plus all of the entries)
bucketCountMaximum ulong Maximum Bucket Count The maximum bucket length (entries in a single bucket)
bucketCountAverage float Average Bucket Count The average bucket length
bucketCountVariance float Bucket Count Variance How far bucket lengths are spread out from their average value
bucketCountStandardDeviation float Bucket Count Standard Deviation How far bucket lengths are spread out from their mean (expected) value
insertionRate float Insertion Rate How many items were added since last event (per second)
removalRate float Removal Rate How many items were removed since last event (per second)

Examples 3
Example event data values and properties
bucketCount ulong
65536
bucketCountAverage float
1.8922119
bucketCountMaximum ulong
13
bucketCountStandardDeviation float
1.3625736
bucketCountVariance float
1.8566068
entryCount ulong
124008
insertionRate float
566.68225
removalRate float
20.0165
startTime long: millis
287792451298
totalFootprint ulong: bytes
13381056
Example event data values and properties
bucketCount ulong
65536
bucketCountAverage float
0.104019165
bucketCountMaximum ulong
3
bucketCountStandardDeviation float
0.3237219
bucketCountVariance float
0.10479586
entryCount ulong
6817
insertionRate float
38.64283
removalRate float
0.39331123
startTime long: millis
20603284143
totalFootprint ulong: bytes
1046608
Example event data values and properties
bucketCount ulong
65536
bucketCountAverage float
2.011795
bucketCountMaximum ulong
12
bucketCountStandardDeviation float
1.413695
bucketCountVariance float
1.9985334
entryCount ulong
131845
insertionRate float
575.86816
removalRate float
41.297318
startTime long: millis
598907308925
totalFootprint ulong: bytes
14276992

PlaceholderTableStatistics

profiling startTime duration every chunk 17 until JDK 20

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:

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(PlaceholderTableStatistics) {
  TableStatistics statistics = SystemDictionary::placeholders_statistics();
  emit_table_statistics<EventPlaceholderTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(LoaderConstraintsTableStatistics) {
  TableStatistics statistics = SystemDictionary::loader_constraints_statistics();
  emit_table_statistics<EventLoaderConstraintsTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(ProtectionDomainCacheTableStatistics) {
  TableStatistics statistics = SystemDictionary::protection_domain_cache_statistics();
  emit_table_statistics<EventProtectionDomainCacheTableStatistics>(statistics);
}

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

Event fields with their types and descriptions
Field Type Description
bucketCount ulong Bucket Count Number of buckets
entryCount ulong Entry Count Number of all entries
totalFootprint ulong: bytes Total Footprint Total memory footprint (the table itself plus all of the entries)
bucketCountMaximum ulong Maximum Bucket Count The maximum bucket length (entries in a single bucket)
bucketCountAverage float Average Bucket Count The average bucket length
bucketCountVariance float Bucket Count Variance How far bucket lengths are spread out from their average value
bucketCountStandardDeviation float Bucket Count Standard Deviation How far bucket lengths are spread out from their mean (expected) value
insertionRate float Insertion Rate How many items were added since last event (per second)
removalRate float Removal Rate How many items were removed since last event (per second)

LoaderConstraintsTableStatistics

profiling startTime duration every chunk 17 until JDK 20

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:

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

TRACE_REQUEST_FUNC(PlaceholderTableStatistics) {
  TableStatistics statistics = SystemDictionary::placeholders_statistics();
  emit_table_statistics<EventPlaceholderTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(LoaderConstraintsTableStatistics) {
  TableStatistics statistics = SystemDictionary::loader_constraints_statistics();
  emit_table_statistics<EventLoaderConstraintsTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(ProtectionDomainCacheTableStatistics) {
  TableStatistics statistics = SystemDictionary::protection_domain_cache_statistics();
  emit_table_statistics<EventProtectionDomainCacheTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(CompilerStatistics) {
  EventCompilerStatistics event;
  event.set_compileCount(CompileBroker::get_total_compile_count());
  event.set_bailoutCount(CompileBroker::get_total_bailout_count());

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

Event fields with their types and descriptions
Field Type Description
bucketCount ulong Bucket Count
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)

ProtectionDomainCacheTableStatistics

profiling startTime duration every chunk 17 until JDK 20

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:

TRACE_REQUEST_FUNC(PlaceholderTableStatistics) {
  TableStatistics statistics = SystemDictionary::placeholders_statistics();
  emit_table_statistics<EventPlaceholderTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(LoaderConstraintsTableStatistics) {
  TableStatistics statistics = SystemDictionary::loader_constraints_statistics();
  emit_table_statistics<EventLoaderConstraintsTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(ProtectionDomainCacheTableStatistics) {
  TableStatistics statistics = SystemDictionary::protection_domain_cache_statistics();
  emit_table_statistics<EventProtectionDomainCacheTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(CompilerStatistics) {
  EventCompilerStatistics event;
  event.set_compileCount(CompileBroker::get_total_compile_count());
  event.set_bailoutCount(CompileBroker::get_total_bailout_count());
  event.set_invalidatedCount(CompileBroker::get_total_invalidated_count());
  event.set_osrCompileCount(CompileBroker::get_total_osr_compile_count());
  event.set_standardCompileCount(CompileBroker::get_total_standard_compile_count());
  event.set_osrBytesCompiled(CompileBroker::get_sum_osr_bytes_compiled());
  event.set_standardBytesCompiled(CompileBroker::get_sum_standard_bytes_compiled());

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

Event fields with their types and descriptions
Field Type Description
bucketCount ulong Bucket Count Number of buckets
entryCount ulong Entry Count Number of all entries
totalFootprint ulong: bytes Total Footprint Total memory footprint (the table itself plus all of the entries)
bucketCountMaximum ulong Maximum Bucket Count The maximum bucket length (entries in a single bucket)
bucketCountAverage float Average Bucket Count The average bucket length
bucketCountVariance float Bucket Count Variance How far bucket lengths are spread out from their average value
bucketCountStandardDeviation float Bucket Count Standard Deviation How far bucket lengths are spread out from their mean (expected) value
insertionRate float Insertion Rate How many items were added since last event (per second)
removalRate float Removal Rate How many items were removed since last event (per second)

ThreadDump

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

Category: Java Virtual Machine / Runtime

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

Missing in: graalvm_linux_native

Code Context

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

src/hotspot/share/jfr/periodic/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_endtime(*(JfrTicks*) param);
  event.commit();

Event configuration settings across JFR profiles
Configuration enabled period
profiling true 60 s
default true everyChunk

Event fields with their types and descriptions
Field Type Description
result string Thread Dump

Examples 3
Example event data values and properties
result string
2026-10-04 01:15:04 Full thread dump OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x00007fb536dc1b60, length=51, elements={ 0x00007fb57c053be0, 0x00007fb57c0ca390, 0x00007fb57c0cbf80, 0x00007fb57c0cdfc0, 0x00007fb57c0cfca0, 0x00007fb57c0d1…
startTime long: millis
598907311891
Example event data values and properties
result string
2026-10-04 01:09:51 Full thread dump OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x00007fa395674e60, length=25, elements={ 0x00007fa394055900, 0x00007fa394155cb0, 0x00007fa394157b10, 0x00007fa394159fe0, 0x00007fa39415bf20, 0x00007fa39415d…
startTime long: millis
10433225517
Example event data values and properties
result string
2026-10-04 01:09:24 Full thread dump OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x00007fc611da9540, length=52, elements={ 0x00007fc654053c00, 0x00007fc654142160, 0x00007fc654143d80, 0x00007fc654145df0, 0x00007fc654147c30, 0x00007fc654149…
startTime long: millis
287792457728

NativeLibrary

profiling default startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime

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

Missing in: graalvm_linux_native

Information about a dynamic library or other native image loaded by the JVM process

Code Context

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

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

TRACE_REQUEST_FUNC(ExecutionSample) {
}
TRACE_REQUEST_FUNC(NativeMethodSample) {
}

TRACE_REQUEST_FUNC(ThreadDump) {
  ResourceMark rm;
  EventThreadDump event;
  event.set_result(JfrDcmdEvent::thread_dump());
  event.commit();
}

static int _native_library_callback(const char* name, address base, address top, void *param) {
  EventNativeLibrary event(UNTIMED);
  event.set_name(name);
  event.set_baseAddress((u8)base);
  event.set_topAddress((u8)top);
  event.set_endtime(*(JfrTicks*) param);
  event.commit();
  return 0;
}

TRACE_REQUEST_FUNC(NativeLibrary) {
  JfrTicks ts= JfrTicks::now();
  os::get_loaded_modules_info(&_native_library_callback, (void *)&ts);

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

Event fields with their types and descriptions
Field Type Description
name string Name
baseAddress ulong: address Base Address Starting address of the module
topAddress ulong: address Top Address Ending address of the module, if available

Examples 3
Example event data values and properties
baseAddress ulong: address
140489882013696
name string
/opt/hostedtoolcache/Java_SapMachine_jdk/25.0.4-1/x64/lib/libzip.so
startTime long: millis
267898481777
topAddress ulong: address
140489882054656
Example event data values and properties
baseAddress ulong: address
140340650319872
name string
/lib/x86_64-linux-gnu/libz.so.1
startTime long: millis
213723079
topAddress ulong: address
140340650434560
Example event data values and properties
baseAddress ulong: address
140417601957888
name string
/lib/x86_64-linux-gnu/libz.so.1
startTime long: millis
544274477390
topAddress ulong: address
140417602072576

ModuleRequire

profiling default startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime / Modules

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

Missing in: graalvm_linux_native

A directed edge representing a dependency

Code Context

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

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

   ModuleDependencyClosure(const ModuleEntry* module, EventFunc ef) : ModuleEventCallbackClosure(ef), _module(module) {}
   void do_module(ModuleEntry* entry);
};

class ModuleExportClosure : public ModuleEventCallbackClosure {
 private:
  const PackageEntry* const _package;
 public:
  ModuleExportClosure(const PackageEntry* pkg, EventFunc ef) : ModuleEventCallbackClosure(ef), _package(pkg) {}
  void do_module(ModuleEntry* entry);
};

static void write_module_dependency_event(const void* from_module, const ModuleEntry* to_module) {
  EventModuleRequire event(UNTIMED);
  event.set_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_endtime(invocation_time);
  event.set_exportedPackage((const PackageEntry*)package);
  event.set_targetModule(qualified_export);

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

Event fields with their types and descriptions
Field Type Description
source Module Source Module
requiredModule Module Required Module

Examples 3
Example event data values and properties
requiredModule Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
source Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
jrt:/jdk.compiler
name string
jdk.compiler
version string
25.0.4.1
startTime long: millis
5420745473
Example event data values and properties
requiredModule Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
source Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
jdk.proxy3
version string
null
startTime long: millis
542255991542
Example event data values and properties
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
25.0.4.1
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
25.0.4.1
name string
java/net
location string
null
name string
jdk.proxy12
version string
null
startTime long: millis
268974264783

ModuleExport

profiling startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime / Modules

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

Missing in: graalvm_linux_native

Code Context

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

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

  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_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_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");
  assert(_event_func != NULL, "invariant");

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

Event fields with their types and descriptions
Field Type Description
exportedPackage Package Exported Package
targetModule Module Target Module Module to which the package is qualifiedly exported. If null or N/A, the package is unqualifiedly exported

Examples 3
Example event data values and properties
exportedPackage Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.xml
name string
java.xml
version string
25.0.4.1
name string
javax/xml/transform/stax
startTime long: millis
5420781066
targetModule Module
null
Example event data values and properties
exportedPackage Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.xml
name string
java.xml
version string
25.0.4.1
name string
org/w3c/dom/ls
startTime long: millis
542256389049
targetModule Module
null
Example event data values and properties
exportedPackage Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
jrt:/jdk.internal.md
name string
jdk.internal.md
version string
25.0.4.1
name string
jdk/internal/org/commonmark/parser
startTime long: millis
268974667621
targetModule Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
jrt:/jdk.javadoc
name string
jdk.javadoc
version string
25.0.4.1

Java Application

ThreadStart

profiling default startTime eventThread stackTrace graal vm only

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/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_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();
    }
  }
}

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

                            JavaThread::name_for(JNIHandles::resolve_non_null(jthread)));
    // No one should hold a reference to the 'native_thread'.
    native_thread->smr_delete();
    if (JvmtiExport::should_post_resource_exhausted()) {
      JvmtiExport::post_resource_exhausted(
        JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR | JVMTI_RESOURCE_EXHAUSTED_THREADS,
        os::native_thread_creation_failed_msg());
    }
    THROW_MSG(vmSymbols::java_lang_OutOfMemoryError(),
              os::native_thread_creation_failed_msg());
  }

#if INCLUDE_JFR
  if (Jfr::is_recording() && EventThreadStart::is_enabled() &&
      EventThreadStart::is_stacktrace_enabled()) {
    JfrThreadLocal* tl = native_thread->jfr_thread_local();
    // skip Thread.start() and Thread.start0()
    tl->set_cached_stack_trace_id(JfrStackTraceRepository::record(thread, 2));
  }
#endif

  Thread::start(native_thread);

JVM_END

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

void JfrThreadLocal::set_thread_blob(const JfrBlobHandle& ref) {
  assert(!_thread.valid(), "invariant");
  _thread = ref;
}

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

static void send_java_thread_start_event(JavaThread* jt) {
  EventThreadStart event;
  event.set_thread(jt->jfr_thread_local()->thread_id());
  event.set_parentThread(jt->jfr_thread_local()->parent_thread_id());
  event.commit();
}

void JfrThreadLocal::on_start(Thread* t) {
  assert(t != NULL, "invariant");
  assert(Thread::current() == t, "invariant");
  JfrJavaSupport::on_thread_start(t);
  if (JfrRecorder::is_recording()) {
    JfrCheckpointManager::write_thread_checkpoint(t);

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

Event fields with their types and descriptions
Field Type Description
thread Thread New Java Thread
parentThread Thread Parent Java Thread

Examples 3
Example event data values and properties
parentThread Thread
group ThreadGroup
name string
UnboundedFuturePool
parent ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
scala-execution-context-global-1988
javaThreadId long
1988
osName string
scala-execution-context-global-1988
osThreadId long
4911
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
2
lineNumber int
2231
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$1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
600135512330
thread Thread
group ThreadGroup
name string
UnboundedFuturePool
parent ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
scala-execution-context-global-1989
javaThreadId long
1989
osName string
scala-execution-context-global-1989
osThreadId long
4912
virtual boolean
false
Example event data values and properties
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
2180
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
12
lineNumber int
249
method 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
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
com/twitter/util/Closable$$anon$7
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
com/twitter/util
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
294835715961
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
CollectClosables
javaThreadId long
1910
osName string
CollectClosables
osThreadId long
4513
virtual boolean
false
Example event data values and properties
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
4621
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
41
lineNumber int
550
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
socketIO
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
945248988
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Thread-1
javaThreadId long
58
osName string
Thread-1
osThreadId long
4685
virtual boolean
false

ThreadEnd

profiling default startTime eventThread graal vm only

Category: Java Application

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

Missing in: graalvm_linux_native

Code Context

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

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

#if INCLUDE_JVMCI
  if (EnableJVMCI) {
    JVMCI::shutdown();
  }
#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_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();

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

  if (t->jfr_thread_local()->has_cached_stack_trace()) {
    t->jfr_thread_local()->clear_cached_stack_trace();
  }
}

static void send_java_thread_end_events(traceid id, JavaThread* jt) {
  assert(jt != NULL, "invariant");
  assert(Thread::current() == jt, "invariant");
  assert(jt->jfr_thread_local()->trace_id() == id, "invariant");
  if (JfrRecorder::is_recording()) {
    EventThreadEnd event;
    event.set_thread(id);
    event.commit();
    JfrThreadCPULoadEvent::send_event_for_thread(jt);
  }
}

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;

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

Event fields with their types and descriptions
Field Type Description
thread Thread Java Thread

Examples 3
Example event data values and properties
startTime long: millis
578690314674
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-storage-async-thread-pool-81
javaThreadId long
1876
osName string
block-manager-storage-async-thread-pool-81
osThreadId long
4774
virtual boolean
false
Example event data values and properties
startTime long: millis
368266200
thread Thread
group ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
C2 CompilerThread1
javaThreadId long
19
osName string
C2 CompilerThread1
osThreadId long
4640
virtual boolean
false
Example event data values and properties
startTime long: millis
283614107316
thread 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
1801
osName string
block-manager-storage-async-thread-pool-71
osThreadId long
4331
virtual boolean
false

ThreadSleep

profiling default startTime duration eventThread stackTrace 11 17 21 25 27 28 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/jvm.cpp:

  // Implied else: If the JavaThread hasn't started yet, then the
  // priority set in the java.lang.Thread object above will be pushed
  // down when it does start.
JVM_END


JVM_ENTRY(void, JVM_Yield(JNIEnv *env, jclass threadClass))
  if (os::dont_yield()) return;
  HOTSPOT_THREAD_YIELD();
  os::naked_yield();
JVM_END

static void post_thread_sleep_event(EventThreadSleep* event, jlong millis) {
  assert(event != NULL, "invariant");
  assert(event->should_commit(), "invariant");
  event->set_time(millis);
  event->commit();
}

JVM_ENTRY(void, JVM_Sleep(JNIEnv* env, jclass threadClass, jlong millis))
  if (millis < 0) {
    THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "timeout value is negative");
  }

  if (thread->is_interrupted(true) && !HAS_PENDING_EXCEPTION) {
    THROW_MSG(vmSymbols::java_lang_InterruptedException(), "sleep interrupted");
  }

  // Save current thread state and restore it at the end of this block.
  // And set new thread state to SLEEPING.
  JavaThreadSleepState jtss(thread);

  HOTSPOT_THREAD_SLEEP_BEGIN(millis);
  EventThreadSleep event;

  if (millis == 0) {
    os::naked_yield();
  } else {
    ThreadState old_state = thread->osthread()->get_state();
    thread->osthread()->set_state(SLEEPING);
    if (!thread->sleep(millis)) { // interrupted
      // An asynchronous exception (e.g., ThreadDeathException) could have been thrown on
      // us while we were sleeping. We do not overwrite those.
      if (!HAS_PENDING_EXCEPTION) {
        if (event.should_commit()) {

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Event fields with their types and descriptions
Field Type Description
time long: millis Sleep Time

Examples 3
Example event data values and properties
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
91
lineNumber int
598
method Method
descriptor string
()J
hidden boolean
false
modifiers int
2
name string
waitForNextTick
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
18
name string
io/netty/util/HashedWheelTimer$Worker
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/util
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
541066344893
time long: millis
10000000
Example event data values and properties
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
12
lineNumber int
49
method Method
descriptor string
()V
hidden boolean
false
modifiers int
4106
name string
lambda$main$0
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
544603027
time long: millis
5000000
Example event data values and properties
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
91
lineNumber int
598
method Method
descriptor string
()J
hidden boolean
false
modifiers int
2
name string
waitForNextTick
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
18
name string
io/netty/util/HashedWheelTimer$Worker
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/util
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
268700178546
time long: millis
9000000

ThreadPark

profiling default startTime duration eventThread stackTrace graal vm only

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_END

UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
  oop p = JNIHandles::resolve(obj);
  if (p == NULL) {
    volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
    return RawAccess<>::atomic_cmpxchg(addr, e, x) == e;
  } else {
    assert_field_offset_sane(p, offset);
    return HeapAccess<>::atomic_cmpxchg_at(p, (ptrdiff_t)offset, 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 {

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Event fields with their types and descriptions
Field Type Description
parkedClass Class Class Parked On
timeout long: nanos Park Timeout
until long: epochmillis Park Until
address ulong: address Address of Object Parked

Examples 3
Example event data values and properties
address ulong: address
30389914104
parkedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionObject
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent/locks
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
type FrameType
Native
…
truncated boolean
false
startTime long: millis
541048458060
timeout long: nanos
119999961517
until long: epochmillis
-9223372036854775808
Example event data values and properties
address ulong: address
30355835520
parkedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionObject
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent/locks
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
type FrameType
Native
…
truncated boolean
false
startTime long: millis
266694457288
timeout long: nanos
58371809217
until long: epochmillis
-9223372036854775808
Example event data values and properties
address ulong: address
0
parkedClass Class
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
type FrameType
Native
…
truncated boolean
false
startTime long: millis
2389910920
timeout long: nanos
1000000
until long: epochmillis
-9223372036854775808

JavaMonitorEnter

profiling default startTime duration eventThread stackTrace graal vm only

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

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Event fields with their types and descriptions
Field Type Description
monitorClass Class Monitor Class
previousOwner Thread Previous Monitor Owner
address ulong: address Monitor Address

Examples 3
Example event data values and properties
address ulong: address
140340561419216
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/jfr/internal/PlatformRecorder
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.jfr
name string
jdk.jfr
version string
25.0.4.1
name string
jdk/jfr/internal
previousOwner Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
4621
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
15
lineNumber int
495
method Method
descriptor string
()V
hidden boolean
false
modifiers int
2
name string
periodicTask
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/jfr/internal/PlatformRecorder
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.jfr
name string
jdk.jfr
version string
25.0.4.1
name string
jdk/jfr/internal
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
213911909
Example event data values and properties
address ulong: address
94850179351856
monitorClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/rpc/netty/Dispatcher
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/rpc/netty
previousOwner Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 3.0 in stage 48.0 (TID 189)
javaThreadId long
1678
osName string
Executor task launch worker for task 3.0 in stage 48.0 (TID 189)
osThreadId long
4208
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
4
lineNumber int
173
method Method
descriptor string
(Ljava/lang/String;Lorg/apache/spark/rpc/netty/InboxMessage;Lscala/Function1;)V
hidden boolean
false
modifiers int
2
name string
postMessage
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/rpc/netty/Dispatcher
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/rpc/netty
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
270012441675
Example event data values and properties
address ulong: address
140416192349312
monitorClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/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
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/scheduler
previousOwner Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
task-result-getter-3
javaThreadId long
1745
osName string
task-result-getter-3
osThreadId long
4643
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
932
method Method
descriptor string
(Lorg/apache/spark/scheduler/TaskSetManager;JLorg/apache/spark/scheduler/DirectTaskResult;)V
hidden boolean
false
modifiers int
33
name string
handleSuccessfulTask
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/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
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/scheduler
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
544099541557

JavaMonitorWait

profiling default startTime duration eventThread stackTrace graal vm only

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,
                                    jlong 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

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Event fields with their types and descriptions
Field Type Description
monitorClass Class Monitor Class Class of object waited on
notifier Thread Notifier Thread Notifying Thread
timeout long: millis Timeout Maximum wait time
timedOut boolean Timed Out Wait has been timed out
address ulong: address Monitor Address Address of object waited on

Examples 3
Example event data values and properties
address ulong: address
140488104443232
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
java/lang/ref/ReferenceQueue$Lock
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang/ref
notifier Thread
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
274
name string
wait0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
268161339108
timedOut boolean
true
timeout long: millis
100
Example event data values and properties
address ulong: address
140340577772624
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Thread
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
notifier Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Thread-38
javaThreadId long
95
osName string
Thread-38
osThreadId long
4722
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
274
name string
wait0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
2032670040
timedOut boolean
false
timeout long: millis
500
Example event data values and properties
address ulong: address
93826296300240
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
notifier Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 3.0 in stage 33.0 (TID 129)
javaThreadId long
1737
osName string
Executor task launch worker for task 3.0 in stage 33.0 (TID 129)
osThreadId long
4634
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
274
name string
wait0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
546798989158
timedOut boolean
false
timeout long: millis
0

JavaMonitorInflate

profiling startTime duration eventThread stackTrace graal vm only

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();
    assert(!mark.has_bias_pattern(), "invariant");

    // 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.
    // *  BIASED       - Illegal.  We should never see this

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
profiling true true 10 ms
default false true 20 ms

Event fields with their types and descriptions
Field Type Description
monitorClass Class Monitor Class
address ulong: address Monitor Address
cause InflateCause Monitor Inflation Cause Cause of inflation

Examples 3
Example event data values and properties
address ulong: address
33676456416
cause InflateCause
Monitor Wait
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
274
name string
wait0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
554281685851
Example event data values and properties
address ulong: address
30200837248
cause InflateCause
Monitor Wait
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Thread
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
274
name string
wait0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
2926619314
Example event data values and properties
address ulong: address
30744446296
cause InflateCause
Monitor Enter
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
537
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
25.0.4.1
name string
java/lang
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
271273924928

ObjectAllocationInNewTLAB

startTime eventThread stackTrace graal vm only

Category: Java Application

Allocation in new Thread Local Allocation Buffer

Code Context

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

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

void AllocTracer::send_allocation_outside_tlab(Klass* klass, HeapWord* obj, size_t alloc_size, JavaThread* thread) {
  JFR_ONLY(JfrAllocationTracer tracer(klass, obj, alloc_size, true, thread);)
  EventObjectAllocationOutsideTLAB event;
  if (event.should_commit()) {
    event.set_objectClass(klass);
    event.set_allocationSize(alloc_size);
    event.commit();
  }
}

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

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

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

Event fields with their types and descriptions
Field Type Description
objectClass Class Object Class Class of allocated object
allocationSize ulong: bytes Allocation Size
tlabSize ulong: bytes TLAB Size

Examples 3
Example event data values and properties
allocationSize ulong: bytes
4112
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
24
lineNumber int
494
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
allocateAndGC
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
383263076
tlabSize ulong: bytes
15352
Example event data values and properties
allocationSize ulong: bytes
16
objectClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
scala/util/Success
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/util
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
103
lineNumber int
467
method Method
descriptor string
()V
hidden boolean
false
modifiers int
17
name string
run
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
25
name string
scala/concurrent/impl/Promise$Transformation
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/concurrent/impl
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
540786738086
tlabSize ulong: bytes
450712
Example event data values and properties
allocationSize ulong: bytes
32
objectClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
breeze/linalg/DenseVector$mcD$sp
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
35
lineNumber int
134
method Method
descriptor string
()Lbreeze/linalg/DenseVector;
hidden boolean
false
modifiers int
1
name string
copy$mcD$sp
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
breeze/linalg/DenseVector$mcD$sp
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
267232203049
tlabSize ulong: bytes
859704

ObjectAllocationOutsideTLAB

startTime eventThread stackTrace 11 17 21 25 27 28

Category: Java Application

Allocation outside Thread Local Allocation Buffers

Code Context

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

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

#if INCLUDE_JFR
#include "jfr/support/jfrAllocationTracer.hpp"
#endif

void AllocTracer::send_allocation_outside_tlab(Klass* klass, HeapWord* obj, size_t alloc_size, JavaThread* thread) {
  JFR_ONLY(JfrAllocationTracer tracer(klass, obj, alloc_size, true, thread);)
  EventObjectAllocationOutsideTLAB event;
  if (event.should_commit()) {
    event.set_objectClass(klass);
    event.set_allocationSize(alloc_size);
    event.commit();
  }
}

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

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

Event fields with their types and descriptions
Field Type Description
objectClass Class Object Class Class of allocated object
allocationSize ulong: bytes Allocation Size

Examples 3
Example event data values and properties
allocationSize ulong: bytes
190208
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
15
lineNumber int
3537
method Method
descriptor string
([BI)[B
hidden boolean
false
modifiers int
9
name string
copyOf
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/util/Arrays
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
268165362714
Example event data values and properties
allocationSize ulong: bytes
1048592
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
6
lineNumber int
75
method Method
descriptor string
(IILjava/lang/foreign/MemorySegment;)V
hidden boolean
false
modifiers int
0
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/nio/HeapByteBuffer
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/nio
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
541635001624
Example event data values and properties
allocationSize ulong: bytes
4112
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
24
lineNumber int
494
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
allocateAndGC
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
373917915

ObjectAllocationSample

throttle profiling default startTime eventThread stackTrace 16 17 21 25 27 28 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/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 size_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 size_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;
}

Event configuration settings across JFR profiles
Configuration enabled stackTrace throttle
profiling true true 300/s
default true true 150/s

Event fields with their types and descriptions
Field Type Description
objectClass Class Object Class Class of allocated object
weight long: bytes Sample Weight The relative weight of the sample. Aggregating the weights for a large number of samples, for a particular class, thread or stack trace, gives a statistically accurate representation of the allocation pressure

Examples 3
Example event data values and properties
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
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
25.0.4.1
name string
java/util/concurrent
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
25.0.4.1
name string
java/util/concurrent
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
540504219579
weight long: bytes
2192
Example event data values and properties
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[D
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
11
lineNumber int
4083
method Method
descriptor string
([DII)[D
hidden boolean
false
modifiers int
9
name string
copyOfRange
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/util/Arrays
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
268139350959
weight long: bytes
1047936
Example event data values and properties
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
24
lineNumber int
494
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
allocateAndGC
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
374214717
weight long: bytes
69904

FileRead

profiling default startTime duration stackTrace 11 17 21 25 27 28

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

Category: Java Application

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/Handlers.java:

package jdk.jfr.events;
import jdk.jfr.internal.handlers.EventHandler;
import jdk.jfr.internal.Utils;

public final class Handlers {
    public static final EventHandler SOCKET_READ = Utils.getHandler(SocketReadEvent.class);
    public static final EventHandler SOCKET_WRITE = Utils.getHandler(SocketWriteEvent.class);
    public static final EventHandler FILE_READ = Utils.getHandler(FileReadEvent.class);
    public static final EventHandler FILE_WRITE = Utils.getHandler(FileWriteEvent.class);
    public static final EventHandler FILE_FORCE = Utils.getHandler(FileForceEvent.class);
    public static final EventHandler ERROR_THROWN = Utils.getHandler(ErrorThrownEvent.class);
    public static final EventHandler EXCEPTION_THROWN = Utils.getHandler(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
    // EventHandler::write(..., String, long, boolean)

    @Label("Path")
    @Description("Full path of the file")
    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/handlers/EventHandler.java:

    public void write(long start, long duration, String host, String address, int port, long timeout, long bytesRead, boolean endOfSTream) {
        throwError("SocketReadEvent");
    }

    public void write(long start, long duration, String host, String address, int port, long bytesWritten) {
        throwError("SocketWriteEvent");
    }

    public void write(long start, long duration, String path, boolean metadata) {
        throwError("FileForceEvent");
    }

    public void write(long start, long duration, String path, long bytesRead, boolean endOfFile) {
        throwError("FileReadEvent");
    }

    public void write(long start, long duration, String path, long bytesWritten) {
        throwError("FileWriteEvent");
    }

    public void write(long start, long duration, String path, Class<?> exceptionClass)  {
        throwError("ExceptionThrownEvent or ErrorThrownEvent");
    }

    private void throwError(String classes) {

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,
        TLSHandshakeEvent.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,

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Event fields with their types and descriptions
Field Type Description
path string Path Full path of the file
bytesRead long: bytes Bytes Read Number of bytes read from the file (possibly 0)
endOfFile boolean End of File If end of file was reached

Examples 3
Example event data values and properties
bytesRead long: bytes
1024
endOfFile boolean
false
path string
/tmp/jfr_sample4219939425627224800.tmp
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
68
lineNumber int
528
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
fileIO
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1087220560
Example event data values and properties
bytesRead long: bytes
8192
endOfFile boolean
false
path string
/tmp/jar_cache9716491885101278582.tmp
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
24
lineNumber int
1588
method Method
descriptor string
([BIIJ)I
hidden boolean
false
modifiers int
18
name string
readAt
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
java/util/zip/ZipFile$Source
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/zip
type FrameType
Inlined
…
truncated boolean
true
startTime long: millis
542006999029
Example event data values and properties
bytesRead long: bytes
8192
endOfFile boolean
false
path string
/tmp/jar_cache947269127500866618.tmp
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
24
lineNumber int
1588
method Method
descriptor string
([BIIJ)I
hidden boolean
false
modifiers int
18
name string
readAt
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
java/util/zip/ZipFile$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
25.0.4.1
name string
java/util/zip
type FrameType
Inlined
…
truncated boolean
true
startTime long: millis
268276543368

FileForce

profiling default startTime duration stackTrace 11 17 21 25 27 28

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

Category: Java Application

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Force updates to be written to file

Code Context

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

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

package jdk.jfr.events;
import jdk.jfr.internal.handlers.EventHandler;
import jdk.jfr.internal.Utils;

public final class Handlers {
    public static final EventHandler SOCKET_READ = Utils.getHandler(SocketReadEvent.class);
    public static final EventHandler SOCKET_WRITE = Utils.getHandler(SocketWriteEvent.class);
    public static final EventHandler FILE_READ = Utils.getHandler(FileReadEvent.class);
    public static final EventHandler FILE_WRITE = Utils.getHandler(FileWriteEvent.class);
    public static final EventHandler FILE_FORCE = Utils.getHandler(FileForceEvent.class);
    public static final EventHandler ERROR_THROWN = Utils.getHandler(ErrorThrownEvent.class);
    public static final EventHandler EXCEPTION_THROWN = Utils.getHandler(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
    // EventHandler::write(..., 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/handlers/EventHandler.java:

    public boolean setRegistered(boolean registered) {
       return platformEventType.setRegistered(registered);
    }

    public void write(long start, long duration, String host, String address, int port, long timeout, long bytesRead, boolean endOfSTream) {
        throwError("SocketReadEvent");
    }

    public void write(long start, long duration, String host, String address, int port, long bytesWritten) {
        throwError("SocketWriteEvent");
    }

    public void write(long start, long duration, String path, boolean metadata) {
        throwError("FileForceEvent");
    }

    public void write(long start, long duration, String path, long bytesRead, boolean endOfFile) {
        throwError("FileReadEvent");
    }

    public void write(long start, long duration, String path, long bytesWritten) {
        throwError("FileWriteEvent");
    }

    public void write(long start, long duration, String path, Class<?> exceptionClass)  {

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,
        TLSHandshakeEvent.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,

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Event fields with their types and descriptions
Field Type Description
path string Path Full path of the file
metaData boolean Update Metadata Whether the file metadata is updated

Examples 3
Example event data values and properties
metaData boolean
true
path string
/tmp/jfr_sample13016198357953434964.tmp
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
47
lineNumber int
536
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
fileForce
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
4777834612
Example event data values and properties
metaData boolean
true
path string
/tmp/jfr_sample1847013260357790073.tmp
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
47
lineNumber int
536
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
fileForce
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
2652184583
Example event data values and properties
metaData boolean
true
path string
/tmp/jfr_sample4219939425627224800.tmp
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
47
lineNumber int
536
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
fileForce
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1534456306

JavaErrorThrow

profiling default startTime duration stackTrace 11 17 21 25 27 28

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

Category: Java Application

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

Missing in: graalvm_linux_native

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

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

Event fields with their types and descriptions
Field Type Description
message string Message
thrownClass Class Class

Examples 3
Example event data values and properties
message string
'java.lang.Object java.lang.invoke.Invokers$Holder.linkToTargetMethod(java.lang.Object, java.lang.Object, int, long, java.lang.Object)'
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
16
lineNumber int
74
method Method
descriptor string
(Ljava/lang/String;)V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Error
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Inlined
…
truncated boolean
true
startTime long: millis
288387097838
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/NoSuchMethodError
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
Example event data values and properties
message string
'java.lang.Object java.lang.invoke.DirectMethodHandle$Holder.invokeSpecialIFC(java.lang.Object, java.lang.Object, java.lang.Object, java.lang.Object, int, java.lang.Object, java.lang.Object)'
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
16
lineNumber int
74
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
25.0.4.1
name string
java/lang
type FrameType
Inlined
…
truncated boolean
true
startTime long: millis
587863511275
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/NoSuchMethodError
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
Example event data values and properties
message string
Native Library /opt/hostedtoolcache/Java_SapMachine_jdk/25.0.4-1/x64/lib/libnet.so already loaded in another classloader
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
16
lineNumber int
74
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
25.0.4.1
name string
java/lang
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
858513683
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/UnsatisfiedLinkError
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang

SocketWrite

profiling default startTime duration stackTrace 11 17 21 25 27 28 graal vm

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

Category: Java Application

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Writing data to a socket

Code Context

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

src/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
    // EventHandler::write(..., 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/Handlers.java:

package jdk.jfr.events;
import jdk.jfr.internal.handlers.EventHandler;
import jdk.jfr.internal.Utils;

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

src/jdk.jfr/share/classes/jdk/jfr/internal/handlers/EventHandler.java:

    public boolean isRegistered() {
        return platformEventType.isRegistered();
    }

    public boolean setRegistered(boolean registered) {
       return platformEventType.setRegistered(registered);
    }

    public void write(long start, long duration, String host, String address, int port, long timeout, long bytesRead, boolean endOfSTream) {
        throwError("SocketReadEvent");
    }

    public void write(long start, long duration, String host, String address, int port, long bytesWritten) {
        throwError("SocketWriteEvent");
    }

    public void write(long start, long duration, String path, boolean metadata) {
        throwError("FileForceEvent");
    }

    public void write(long start, long duration, String path, long bytesRead, boolean endOfFile) {
        throwError("FileReadEvent");
    }

    public void write(long start, long duration, String path, long bytesWritten) {

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

        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        TLSHandshakeEvent.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.TLSHandshakeEvent.class,
        jdk.internal.event.X509CertificateEvent.class,

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Event fields with their types and descriptions
Field Type Description
host string Remote Host
address string Remote Address
port int Remote Port
bytesWritten long: bytes Bytes Written Number of bytes written to the socket

Examples 3
Example event data values and properties
address string
127.0.0.1
bytesWritten long: bytes
64
host string
127.0.0.1
port int
33380
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
69
lineNumber int
553
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
socketIO
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
2311837660
Example event data values and properties
address string
127.0.0.1
bytesWritten long: bytes
64
host string
127.0.0.1
port int
41091
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
20
lineNumber int
546
method Method
descriptor string
(I)V
hidden boolean
false
modifiers int
4106
name string
lambda$socketIO$0
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
1063486408
Example event data values and properties
address string
127.0.0.1
bytesWritten long: bytes
64
host string
127.0.0.1
port int
42330
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
69
lineNumber int
553
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
socketIO
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
2799394978

FileWrite

profiling default startTime duration stackTrace 11 17 21 25 27 28

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

Category: Java Application

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
    // EventHandler::write(..., String, long)

    @Label("Path")
    @Description("Full path of the file")
    public String path;

    @Label("Bytes Written")
    @Description("Number of bytes written to the file")
    @DataAmount

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

package jdk.jfr.events;
import jdk.jfr.internal.handlers.EventHandler;
import jdk.jfr.internal.Utils;

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

src/jdk.jfr/share/classes/jdk/jfr/internal/handlers/EventHandler.java:

    public void write(long start, long duration, String host, String address, int port, long bytesWritten) {
        throwError("SocketWriteEvent");
    }

    public void write(long start, long duration, String path, boolean metadata) {
        throwError("FileForceEvent");
    }

    public void write(long start, long duration, String path, long bytesRead, boolean endOfFile) {
        throwError("FileReadEvent");
    }

    public void write(long start, long duration, String path, long bytesWritten) {
        throwError("FileWriteEvent");
    }

    public void write(long start, long duration, String path, Class<?> exceptionClass)  {
        throwError("ExceptionThrownEvent or ErrorThrownEvent");
    }

    private void throwError(String classes) {
        throw new InternalError("Method parameters don't match fields in class " + classes);
    }
}

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

    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        TLSHandshakeEvent.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,

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Event fields with their types and descriptions
Field Type Description
path string Path Full path of the file
bytesWritten long: bytes Bytes Written Number of bytes written to the file

Examples 3
Example event data values and properties
bytesWritten long: bytes
8140
path string
/tmp/jar_cache10957131668523381866.tmp
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
38
lineNumber int
796
method Method
descriptor string
(Ljava/io/OutputStream;)J
hidden boolean
false
modifiers int
1
name string
transferTo
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/io/InputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/io
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
286484307564
Example event data values and properties
bytesWritten long: bytes
1
path string
/tmp/jfr_agent7992891143753181003.jar
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
27
lineNumber int
844
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
2
name string
writeInt
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/zip/ZipOutputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/zip
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
238408096
Example event data values and properties
bytesWritten long: bytes
8347
path string
/tmp/jar_cache1591071311148229109.tmp
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
38
lineNumber int
796
method Method
descriptor string
(Ljava/io/OutputStream;)J
hidden boolean
false
modifiers int
1
name string
transferTo
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/io/InputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/io
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
582931722582

JavaExceptionThrow

startTime duration stackTrace 11 17 21 25 27 28

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

Category: Java Application

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

Missing in: graalvm_linux_native

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

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

Event fields with their types and descriptions
Field Type Description
message string Message
thrownClass Class Class

Examples 3
Example event data values and properties
message string
jfr_sample.Main$4.readObjectNoData()
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
44
lineNumber int
286
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/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
25.0.4.1
name string
java/lang
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
875955743
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/NoSuchMethodException
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
Example event data values and properties
message string
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
39
lineNumber int
266
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
25.0.4.1
name string
java/lang
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
268934415266
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Exception
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
Example event data values and properties
message string
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
39
lineNumber int
266
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
25.0.4.1
name string
java/lang
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
541278759926
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Exception
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang

SocketRead

profiling default startTime duration stackTrace 11 17 21 25 27 28 graal vm

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

Category: Java Application

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Reading data from a socket

Code Context

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

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

package jdk.jfr.events;
import jdk.jfr.internal.handlers.EventHandler;
import jdk.jfr.internal.Utils;

public final class Handlers {
    public static final EventHandler SOCKET_READ = Utils.getHandler(SocketReadEvent.class);
    public static final EventHandler SOCKET_WRITE = Utils.getHandler(SocketWriteEvent.class);
    public static final EventHandler FILE_READ = Utils.getHandler(FileReadEvent.class);
    public static final EventHandler FILE_WRITE = Utils.getHandler(FileWriteEvent.class);
    public static final EventHandler FILE_FORCE = Utils.getHandler(FileForceEvent.class);
    public static final EventHandler ERROR_THROWN = Utils.getHandler(ErrorThrownEvent.class);
    public static final EventHandler EXCEPTION_THROWN = Utils.getHandler(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
    // EventHandler::write(..., 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/handlers/EventHandler.java:

    private final void readObject(ObjectInputStream in) throws IOException {
        throw new IOException("Class cannot be deserialized");
    }

    public boolean isRegistered() {
        return platformEventType.isRegistered();
    }

    public boolean setRegistered(boolean registered) {
       return platformEventType.setRegistered(registered);
    }

    public void write(long start, long duration, String host, String address, int port, long timeout, long bytesRead, boolean endOfSTream) {
        throwError("SocketReadEvent");
    }

    public void write(long start, long duration, String host, String address, int port, long bytesWritten) {
        throwError("SocketWriteEvent");
    }

    public void write(long start, long duration, String path, boolean metadata) {
        throwError("FileForceEvent");
    }

    public void write(long start, long duration, String path, long bytesRead, boolean endOfFile) {

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

        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        TLSHandshakeEvent.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.TLSHandshakeEvent.class,

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Event fields with their types and descriptions
Field Type Description
host string Remote Host
address string Remote Address
port int Remote Port
timeout long: millis Timeout Value
bytesRead long: bytes Bytes Read Number of bytes read from the socket
endOfStream boolean End of Stream If end of stream was reached

Examples 3
Example event data values and properties
address string
127.0.0.1
bytesRead long: bytes
64
endOfStream boolean
false
host string
127.0.0.1
port int
40929
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
31
lineNumber int
547
method Method
descriptor string
(I)V
hidden boolean
false
modifiers int
4106
name string
lambda$socketIO$0
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
2228102714
timeout long: millis
0
Example event data values and properties
address string
127.0.0.1
bytesRead long: bytes
64
endOfStream boolean
false
host string
127.0.0.1
port int
43772
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
57
lineNumber int
552
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
socketIO
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1705962833
timeout long: millis
0
Example event data values and properties
address string
127.0.0.1
bytesRead long: bytes
64
endOfStream boolean
false
host string
127.0.0.1
port int
43120
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
57
lineNumber int
552
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
socketIO
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
2916155304
timeout long: millis
0

Java Application Statistics

JavaThreadStatistics

profiling default startTime duration every chunk graal vm only

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) {
  EventClassLoadingStatistics event;
  event.set_loadedClassCount(ClassLoadingService::loaded_class_count());
  event.set_unloadedClassCount(ClassLoadingService::unloaded_class_count());

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

Event fields with their types and descriptions
Field Type Description
activeCount long Active Threads Number of live active threads including both daemon and non-daemon threads
daemonCount long Daemon Threads Number of live daemon threads
accumulatedCount long Accumulated Threads Number of threads created and also started since JVM start
peakCount long Peak Threads Peak live thread count since JVM start or when peak count was reset

Examples 3
Example event data values and properties
accumulatedCount long
399
activeCount long
21
daemonCount long
16
peakCount long
22
startTime long: millis
12466429233
Example event data values and properties
accumulatedCount long
1962
activeCount long
70
daemonCount long
65
peakCount long
297
startTime long: millis
600995695269
Example event data values and properties
accumulatedCount long
1845
activeCount long
295
daemonCount long
294
peakCount long
297
startTime long: millis
282402520022

ClassLoadingStatistics

profiling default startTime duration every chunk graal vm only

Category: Java Application / Statistics

Code Context

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

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

  event.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) {
  EventClassLoadingStatistics event;
  event.set_loadedClassCount(ClassLoadingService::loaded_class_count());
  event.set_unloadedClassCount(ClassLoadingService::unloaded_class_count());
  event.commit();
}

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 ?

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

Event fields with their types and descriptions
Field Type Description
loadedClassCount long Loaded Class Count Number of classes loaded since JVM start
unloadedClassCount long Unloaded Class Count Number of classes unloaded since JVM start

Examples 3
Example event data values and properties
loadedClassCount long
143449
startTime long: millis
604037433060
unloadedClassCount long
8305
Example event data values and properties
loadedClassCount long
143252
startTime long: millis
300972374804
unloadedClassCount long
9800
Example event data values and properties
loadedClassCount long
4285
startTime long: millis
14545572776
unloadedClassCount long
443

ClassLoaderStatistics

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

Category: Java Application / Statistics

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

Missing in: graalvm_linux_native

Code Context

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

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

  event.set_unloadedClassCount(ClassLoadingService::unloaded_class_count());
  event.commit();
}

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;

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

Event fields with their types and descriptions
Field Type Description
classLoader ClassLoader Class Loader
parentClassLoader ClassLoader Parent Class Loader
classLoaderData ulong: address ClassLoaderData Pointer Pointer to the ClassLoaderData structure in the JVM
classCount long Classes Number of loaded classes
chunkSize ulong: bytes Total Chunk Size Total size of all allocated metaspace chunks (each chunk has several blocks)
blockSize ulong: bytes Total Block Size Total size of all allocated metaspace blocks (each chunk has several blocks)
hiddenClassCount long 15+ Hidden Classes Number of hidden classes
hiddenChunkSize ulong: bytes 15+ Total Hidden Classes Chunk Size Total size of all allocated metaspace chunks for hidden classes (each chunk has several blocks)
hiddenBlockSize ulong: bytes 15+ Total Hidden Classes Block Size Total size of all allocated metaspace blocks for hidden classes (each chunk has several blocks)

Examples 3
Example event data values and properties
blockSize ulong: bytes
323424
chunkSize ulong: bytes
334848
classCount long
79
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
classLoaderData ulong: address
140340541700416
hiddenBlockSize ulong: bytes
0
hiddenChunkSize ulong: bytes
0
hiddenClassCount long
0
parentClassLoader ClassLoader
name string
platform
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$PlatformClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
startTime long: millis
24486492954
Example event data values and properties
blockSize ulong: bytes
5008
chunkSize ulong: bytes
6144
classCount long
2
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
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
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/neo4j/codegen
classLoaderData ulong: address
140487574214816
hiddenBlockSize ulong: bytes
0
hiddenChunkSize ulong: bytes
0
hiddenClassCount long
0
parentClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
startTime long: millis
268969677011
Example event data values and properties
blockSize ulong: bytes
5304
chunkSize ulong: bytes
6144
classCount long
2
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
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
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/neo4j/codegen
classLoaderData ulong: address
140416192920032
hiddenBlockSize ulong: bytes
0
hiddenChunkSize ulong: bytes
0
hiddenClassCount long
0
parentClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
startTime long: millis
542254824668

ThreadAllocationStatistics

profiling default startTime every chunk 11 17 21 25 27 28 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:

  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_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_endtime(time_stamp);
    event.commit();
  }
}

/**
 *  PhysicalMemory event represents:
 *
 *  @totalSize == The amount of physical memory (hw) installed and reported by the OS, in bytes.

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

Event fields with their types and descriptions
Field Type Description
allocated ulong: bytes Allocated Approximate number of bytes allocated since thread start
thread Thread Thread

Examples 3
Example event data values and properties
allocated ulong: bytes
0
startTime long: millis
5420679803
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
JFR Recording Scheduler
javaThreadId long
30
osName string
JFR Recording Scheduler
osThreadId long
4647
virtual boolean
false
Example event data values and properties
allocated ulong: bytes
565824
startTime long: millis
267898405953
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
dispatcher-HeartbeatReceiver
javaThreadId long
1658
osName string
dispatcher-HeartbeatReceiver
osThreadId long
4182
virtual boolean
false
Example event data values and properties
allocated ulong: bytes
32
startTime long: millis
540789457661
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
SparkUI-1716
javaThreadId long
1716
osName string
SparkUI-1716
osThreadId long
4609
virtual boolean
false

ExceptionStatistics

profiling default startTime duration stackTrace 11 17 21 25 27 28

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

Category: Java Application / Statistics

Number of objects derived from java.lang.Throwable that have been created

Code Context

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

src/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:

        SecurityProviderServiceEvent.class,
        TLSHandshakeEvent.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.TLSHandshakeEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,

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

    private static boolean initializationTriggered;

    @SuppressWarnings("unchecked")
    public synchronized static 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();

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

Event fields with their types and descriptions
Field Type Description
throwables long Exceptions Created

Examples 3
Example event data values and properties
startTime long: millis
270917767181
throwables long
2354376
Example event data values and properties
startTime long: millis
20600758229
throwables long
2024
Example event data values and properties
startTime long: millis
545861709887
throwables long
2354082

DirectBufferStatistics

profiling default startTime duration stackTrace 15 17 21 25 27 28

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

Category: Java Application / Statistics

Statistics of direct buffer

Code Context

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

src/jdk.jfr/share/classes/jdk/jfr/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:

        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.TLSHandshakeEvent.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 synchronized static 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();

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

Examples 3
Example event data values and properties
startTime long: millis
298815037633
Example event data values and properties
startTime long: millis
604037848371
Example event data values and properties
startTime long: millis
10431287450

Java Development Kit

Deserialization

startTime duration stackTrace 11 17 21 25 27 28

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

Category: Java Development Kit / Serialization

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

Missing in: graalvm_linux_native

Results of deserialization and ObjectInputFilter checks

Code Context

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

src/java.base/share/classes/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;
}

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,
        TLSHandshakeEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

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

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

Event fields with their types and descriptions
Field Type Description
filterConfigured boolean Filter Configured
filterStatus string Filter Status
type Class Type
arrayLength int Array Length
objectReferences long Object References
depth long Depth
bytesRead long Bytes Read
exceptionType Class Exception Type
exceptionMessage string Exception Message

Examples 3
Example event data values and properties
arrayLength int
-1
bytesRead long
9082
depth long
4
exceptionMessage string
null
exceptionType Class
null
filterConfigured boolean
false
filterStatus string
null
objectReferences long
24
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
304
lineNumber int
1348
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
25.0.4.1
name string
java/io
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
540512815584
type Class
null
Example event data values and properties
arrayLength int
-1
bytesRead long
645
depth long
3
exceptionMessage string
null
exceptionType Class
null
filterConfigured boolean
false
filterStatus string
null
objectReferences long
13
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
304
lineNumber int
1348
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
25.0.4.1
name string
java/io
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
268062010737
type Class
null
Example event data values and properties
arrayLength int
-1
bytesRead long
45
depth long
1
exceptionMessage string
null
exceptionType Class
null
filterConfigured boolean
false
filterStatus string
null
objectReferences long
1
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
304
lineNumber int
1348
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
25.0.4.1
name string
java/io
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
746176027
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/ArrayList
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util

TLSHandshake

startTime duration stackTrace 11 17 21 25 27 28

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

Category: Java Development Kit / Security

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Parameters used in TLS Handshake

Code Context

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

src/java.base/share/classes/sun/security/ssl/Finished.java:

                shc.conContext.finishHandshake();
            }
            recordEvent(shc.conContext.conSession);

            //
            // produce
            if (SSLConfiguration.serverNewSessionTicketCount > 0) {
                NewSessionTicket.t13PosthandshakeProducer.produce(shc);
            }
        }
    }

    private static void recordEvent(SSLSessionImpl session) {
        TLSHandshakeEvent event = new TLSHandshakeEvent();
        if (event.shouldCommit() || EventHelper.isLoggingSecurity()) {
            int peerCertificateId = 0;
            try {
                // use hash code for Id
                peerCertificateId = session
                        .getCertificateChain()[0]
                        .hashCode();
            } catch (SSLPeerUnverifiedException e) {
                 // not verified msg
            }
            if (event.shouldCommit()) {

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/jdk.jfr/share/classes/jdk/jfr/events/TLSHandshakeEvent.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("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,
        TLSHandshakeEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

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

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

Event fields with their types and descriptions
Field Type Description
peerHost string Peer Host
peerPort int Peer Port
protocolVersion string Protocol Version
cipherSuite string Cipher Suite
certificateId long: certificateId Certificate Id Peer Certificate Id

Examples 3
Example event data values and properties
certificateId long: certificateId
288990878
cipherSuite string
TLS_AES_256_GCM_SHA384
peerHost string
example.com
peerPort int
443
protocolVersion string
TLSv1.3
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
422
lineNumber int
768
method Method
descriptor string
(Lsun/security/ssl/ClientHandshakeContext;Lsun/security/ssl/SSLHandshake$HandshakeMessage;)[B
hidden boolean
false
modifiers int
2
name string
onProduceFinished
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
26
name string
sun/security/ssl/Finished$T13FinishedProducer
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
25.0.4.1
name string
sun/security/ssl
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
717227862
Example event data values and properties
certificateId long: certificateId
288990878
cipherSuite string
TLS_AES_256_GCM_SHA384
peerHost string
example.com
peerPort int
443
protocolVersion string
TLSv1.3
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
422
lineNumber int
768
method Method
descriptor string
(Lsun/security/ssl/ClientHandshakeContext;Lsun/security/ssl/SSLHandshake$HandshakeMessage;)[B
hidden boolean
false
modifiers int
2
name string
onProduceFinished
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
26
name string
sun/security/ssl/Finished$T13FinishedProducer
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
25.0.4.1
name string
sun/security/ssl
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
1024518609
Example event data values and properties
certificateId long: certificateId
288990878
cipherSuite string
TLS_AES_256_GCM_SHA384
peerHost string
example.com
peerPort int
443
protocolVersion string
TLSv1.3
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
422
lineNumber int
768
method Method
descriptor string
(Lsun/security/ssl/ClientHandshakeContext;Lsun/security/ssl/SSLHandshake$HandshakeMessage;)[B
hidden boolean
false
modifiers int
2
name string
onProduceFinished
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
26
name string
sun/security/ssl/Finished$T13FinishedProducer
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
25.0.4.1
name string
sun/security/ssl
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
1068409728

InitialSecurityProperty

profiling default startTime duration stackTrace 11 17 21 25 27 28

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

Category: Java Development Kit / Security

Initial Security Properties

Code Context

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

src/jdk.jfr/share/classes/jdk/jfr/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:

        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.TLSHandshakeEvent.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 synchronized static 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();
            }
        }
    }
}

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

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

Examples 3
Example event data values and properties
key string
sun.security.krb5.maxReferrals
startTime long: millis
269469366708
value string
5
Example event data values and properties
key string
jdk.security.legacyAlgorithms
startTime long: millis
543123682379
value string
SHA1, RSA keySize < 2048, DSA keySize < 2048, DES, DESede, MD5, RC2, ARCFOUR
Example event data values and properties
key string
security.provider.4
startTime long: millis
5548970295
value string
SunJSSE

X509Validation

startTime duration stackTrace 11 17 21 25 27 28

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

Category: Java Development Kit / Security

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Serial numbers from X.509 Certificates forming chain of trust

Code Context

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

src/java.base/share/classes/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()) {
            int[] certIds = params.certificates().stream()
                    .mapToInt(Certificate::hashCode)
                    .toArray();
            int anchorCertId = (anchorCert != null) ?
                anchorCert.hashCode() : anchor.getCAPublicKey().hashCode();
            if (xve.shouldCommit()) {
                xve.certificateId = anchorCertId;
                int certificatePos = 1; // most trusted CA
                xve.certificatePosition = certificatePos;
                xve.validationCounter = validationCounter.incrementAndGet();

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/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")
    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,
        TLSHandshakeEvent.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,

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

Event fields with their types and descriptions
Field Type Description
certificateId long: certificateId Certificate Id
certificatePosition int Certificate Position Certificate position in chain of trust, 1 = trust anchor
validationCounter long Validation Counter

Examples 3
Example event data values and properties
certificateId long: certificateId
2389201834
certificatePosition int
2
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
520
lineNumber int
247
method Method
descriptor string
(Ljava/security/cert/TrustAnchor;Lsun/security/provider/certpath/PKIX$ValidatorParams;)Ljava/security/cert/PKIXCertPathValidatorResult;
hidden boolean
false
modifiers int
10
name string
validate
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
sun/security/provider/certpath/PKIXCertPathValidator
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
sun/security/provider/certpath
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
696105956
validationCounter long
1
Example event data values and properties
certificateId long: certificateId
288990878
certificatePosition int
4
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
520
lineNumber int
247
method Method
descriptor string
(Ljava/security/cert/TrustAnchor;Lsun/security/provider/certpath/PKIX$ValidatorParams;)Ljava/security/cert/PKIXCertPathValidatorResult;
hidden boolean
false
modifiers int
10
name string
validate
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
sun/security/provider/certpath/PKIXCertPathValidator
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
sun/security/provider/certpath
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
987774643
validationCounter long
1
Example event data values and properties
certificateId long: certificateId
683561703
certificatePosition int
1
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
472
lineNumber int
242
method Method
descriptor string
(Ljava/security/cert/TrustAnchor;Lsun/security/provider/certpath/PKIX$ValidatorParams;)Ljava/security/cert/PKIXCertPathValidatorResult;
hidden boolean
false
modifiers int
10
name string
validate
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
sun/security/provider/certpath/PKIXCertPathValidator
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
sun/security/provider/certpath
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
1026228971
validationCounter long
1

SecurityProviderService

startTime duration stackTrace 11 17 21 25 27 28

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/java.base/share/classes/java/security/Provider.java:

            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);
                return null;
            }
        }

        if (s != null && SecurityProviderServiceEvent.isTurnedOn()) {
            var e  = new SecurityProviderServiceEvent();
            e.provider = getName();
            e.type = type;
            e.algorithm = algorithm;
            e.commit();
        }

        return s;
    }

    // ServiceKey from previous getService() call
    // by re-using it if possible we avoid allocating a new object

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/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,
        TLSHandshakeEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

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

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

Event fields with their types and descriptions
Field Type Description
type string Type of Service
algorithm string Algorithm Name
provider string Security Provider

Examples 3
Example event data values and properties
algorithm string
MD5
provider string
SUN
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
101
lineNumber int
378
method Method
descriptor string
(Ljava/lang/String;Ljava/lang/String;)Ljava/security/Provider$Service;
hidden boolean
false
modifiers int
1
name string
getService
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
sun/security/jca/ProviderList
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
sun/security/jca
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
293784678605
type string
MessageDigest
Example event data values and properties
algorithm string
X509
provider string
SUN
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
101
lineNumber int
378
method Method
descriptor string
(Ljava/lang/String;Ljava/lang/String;)Ljava/security/Provider$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
17
name string
sun/security/jca/ProviderList
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
sun/security/jca
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
498138215
type string
CertificateFactory
Example event data values and properties
algorithm string
MD5
provider string
SUN
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
101
lineNumber int
378
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
17
name string
sun/security/jca/ProviderList
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
sun/security/jca
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
597168076908
type string
MessageDigest

X509Certificate

startTime duration stackTrace 11 17 21 25 27 28

Source src/jdk.jfr/share/classes/jdk/jfr/events/X509CertificateEvent.java

Category: Java Development Kit / Security

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Details of X.509 Certificate parsed by JDK

Code Context

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

src/java.base/share/classes/sun/security/jca/JCAUtil.java:

        SecureRandom result = def;
        if (result == null) {
            synchronized (JCAUtil.class) {
                result = def;
                if (result == null) {
                    def = result = new SecureRandom();
                }
            }
        }
        return result;
    }

    public static void tryCommitCertEvent(Certificate cert) {
        if ((X509CertificateEvent.isTurnedOn() || EventHelper.isLoggingSecurity()) &&
                (cert instanceof X509Certificate x509)) {
            PublicKey pKey = x509.getPublicKey();
            String algId = x509.getSigAlgName();
            String serNum = Debug.toString(x509.getSerialNumber());
            String subject = x509.getSubjectX500Principal().toString();
            String issuer = x509.getIssuerX500Principal().toString();
            String keyType = pKey.getAlgorithm();
            int length = KeyUtil.getKeySize(pKey);
            int hashCode = x509.hashCode();
            long 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 = hashCode;
                xce.validFrom = beginDate;
                xce.validUntil = endDate;
                xce.commit();
            }

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/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,
        TLSHandshakeEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

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

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

Event fields with their types and descriptions
Field Type Description
algorithm string Signature Algorithm
serialNumber string Serial Number
subject string Subject
issuer string Issuer
keyType string Key Type
keyLength int Key Length
certificateId long: certificateId Certificate Id
validFrom long: epochmillis Valid From
validUntil long: epochmillis Valid Until

Examples 3
Example event data values and properties
algorithm string
SHA256withRSA
certificateId long: certificateId
696763521
issuer string
CN=QuoVadis Root CA 2 G3, O=QuoVadis Limited, C=BM
keyLength int
4096
keyType string
RSA
serialNumber string
44:57:34:24:5b:81:89:9b:35:f2:ce:b8:2b:3b:5b:a7:26:f0:75:28
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
25.0.4.1
name string
sun/security/jca
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
721566937
subject string
CN=QuoVadis Root CA 2 G3, O=QuoVadis Limited, C=BM
validFrom long: epochmillis
1326394772000
validUntil long: epochmillis
2273165972000
Example event data values and properties
algorithm string
SHA384withECDSA
certificateId long: certificateId
3649430051
issuer string
CN=DigiCert Assured ID Root G3, OU=www.digicert.com, O=DigiCert Inc, C=US
keyLength int
384
keyType string
EC
serialNumber string
0b:a1:5a:fa:1d:df:a0:b5:49:44:af:cd:24:a0:6c:ec
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
25.0.4.1
name string
sun/security/jca
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
500636217
subject string
CN=DigiCert Assured ID Root G3, OU=www.digicert.com, O=DigiCert Inc, C=US
validFrom long: epochmillis
1375358400000
validUntil long: epochmillis
2147169600000
Example event data values and properties
algorithm string
SHA256withRSA
certificateId long: certificateId
1714819687
issuer string
CN=LuxTrust Global Root, O=LuxTrust s.a., C=LU
keyLength int
2048
keyType string
RSA
serialNumber string
0b:b8
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
25.0.4.1
name string
sun/security/jca
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
707215333
subject string
CN=LuxTrust Global Root, O=LuxTrust s.a., C=LU
validFrom long: epochmillis
1300355497000
validUntil long: epochmillis
1615974697000

SecurityPropertyModification

startTime duration stackTrace 11 17 21 25 27 28

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

Category: Java Development Kit / Security

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Modification of Security property

Code Context

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

src/java.base/share/classes/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 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);
        }
    }

    /*

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

package jdk.internal.event;

/**
 * Event details relating to the modification of a Security property.
 */

public final class SecurityPropertyModificationEvent extends Event {
    public String key;
    public String value;
}

src/jdk.jfr/share/classes/jdk/jfr/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,
        TLSHandshakeEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

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

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

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

Examples 3
Example event data values and properties
key string
jdk.disabled.namedCurves
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
59
lineNumber int
67
method Method
descriptor string
([Ljava/lang/String;)V
hidden boolean
false
modifiers int
9
name string
main
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1127766211
value string
secp112r1
Example event data values and properties
key string
jdk.disabled.namedCurves
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
59
lineNumber int
67
method Method
descriptor string
([Ljava/lang/String;)V
hidden boolean
false
modifiers int
9
name string
main
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
772579905
value string
secp112r1
Example event data values and properties
key string
jdk.disabled.namedCurves
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
59
lineNumber int
67
method Method
descriptor string
([Ljava/lang/String;)V
hidden boolean
false
modifiers int
9
name string
main
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1088032510
value string
secp112r1

Operating System

OSInformation

profiling default startTime duration end of every chunk graal vm only

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) {

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

Event fields with their types and descriptions
Field Type Description
osVersion string OS Version

Examples 3
Example event data values and properties
osVersion string
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=24.04 DISTRIB_CODENAME=noble DISTRIB_DESCRIPTION="Ubuntu 24.04.5 LTS" uname: Linux 6.17.0-1022-azure #22-Ubuntu SMP Mon Jul 27 17:24:03 UTC 2026 x86_64 libc: glibc 2.39 NPTL 2.39
startTime long: millis
269313884614
Example event data values and properties
osVersion string
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=24.04 DISTRIB_CODENAME=noble DISTRIB_DESCRIPTION="Ubuntu 24.04.5 LTS" uname: Linux 6.17.0-1022-azure #22-Ubuntu SMP Mon Jul 27 17:24:03 UTC 2026 x86_64 libc: glibc 2.39 NPTL 2.39
startTime long: millis
571360838858
Example event data values and properties
osVersion string
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=24.04 DISTRIB_CODENAME=noble DISTRIB_DESCRIPTION="Ubuntu 24.04.5 LTS" uname: Linux 6.17.0-1022-azure #22-Ubuntu SMP Mon Jul 27 17:24:03 UTC 2026 x86_64 libc: glibc 2.39 NPTL 2.39
startTime long: millis
11693259707

VirtualizationInformation

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

Category: Operating System

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

Missing in: graalvm_linux_native

Description of the virtualization technology the JVM runs on

Code Context

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

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

  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();
}

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

Event fields with their types and descriptions
Field Type Description
name string Name

Examples 3
Example event data values and properties
name string
Hyper-V virtualization
startTime long: millis
540789428896
Example event data values and properties
name string
Hyper-V virtualization
startTime long: millis
296627162061
Example event data values and properties
name string
Hyper-V virtualization
startTime long: millis
18034626071

InitialEnvironmentVariable

profiling default startTime end of every chunk graal vm only

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_endtime(time_stamp);
        event.set_key(key);
        event.set_value(value);
        event.commit();
      }
    }
  }
  return OS_OK;
}

int JfrOSInterface::system_processes(SystemProcess** sys_processes, int* no_of_sys_processes) {

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

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

Examples 3
Example event data values and properties
key string
JAVA_HOME_21_X64
startTime long: millis
540789434928
value string
/usr/lib/jvm/temurin-21-jdk-amd64
Example event data values and properties
key string
XDG_CONFIG_HOME
startTime long: millis
213458729
value string
/home/runner/.config
Example event data values and properties
key string
RUNNER_ENVIRONMENT
startTime long: millis
267898388036
value string
github-hosted

SystemProcess

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

Category: Operating System

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

    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;
    }
  }
}

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

Event fields with their types and descriptions
Field Type Description
pid string Process Identifier
commandLine string Command Line

Examples 3
Example event data values and properties
commandLine string
kworker/R-ata_sff
pid string
60
startTime long: millis
23758987685
Example event data values and properties
commandLine string
/usr/bin/python3 /usr/bin/networkd-dispatcher --run-startup-triggers
pid string
1030
startTime long: millis
20509613464
Example event data values and properties
commandLine string
kworker/3:1H-kblockd
pid string
139
startTime long: millis
5417089112

CPUInformation

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

Category: Operating System / Processor

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

Missing in: graalvm_linux_native

Characteristics and descriptions of the processor(s) the JVM is running on

Code Context

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

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

TRACE_REQUEST_FUNC(CPUInformation) {
  CPUInformation cpu_info;
  int ret_val = JfrOSInterface::cpu_information(cpu_info);
  if (ret_val == OS_ERR) {
    log_debug(jfr, system)( "Unable to generate requestable event CPUInformation");
    return;
  }
  if (ret_val == FUNCTIONALITY_NOT_IMPLEMENTED) {
     return;
  }
  if (ret_val == OS_OK) {
    EventCPUInformation event;
    event.set_cpu(cpu_info.cpu_name());
    event.set_description(cpu_info.cpu_description());
    event.set_sockets(cpu_info.number_of_sockets());
    event.set_cores(cpu_info.number_of_cores());
    event.set_hwThreads(cpu_info.number_of_hardware_threads());
    event.commit();
  }
}

TRACE_REQUEST_FUNC(CPULoad) {
  double u = 0; // user time

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

Event fields with their types and descriptions
Field Type Description
cpu string Type
description string Description
sockets uint Sockets
cores uint Cores
hwThreads uint Hardware Threads

Examples 3
Example event data values and properties
cores uint
16
cpu string
AMD Unknown x86 (HT) SSE SSE2 SSE3 SSSE3 SSE4.1 SSE4.2 SSE4A AMD64
description string
Brand: AMD EPYC 7763 64-Core Processor , Vendor: AuthenticAMD Family: Unknown x86 (0x19), Model: <unknown> (0x1), Stepping: 0x1 Ext. family: 0xa, Ext. model: 0x0, Type: 0x0, Signature: 0x00a00f11 Features: ebx: 0x01100800, ecx: 0xfeda3203, edx: 0x178bfbff Ext. features: eax: 0x00a00f1…
hwThreads uint
4
sockets uint
1
startTime long: millis
593532504558
Example event data values and properties
cores uint
16
cpu string
AMD Unknown x86 (HT) SSE SSE2 SSE3 SSSE3 SSE4.1 SSE4.2 SSE4A AMD64
description string
Brand: AMD EPYC 9V45 96-Core Processor , Vendor: AuthenticAMD Family: Unknown x86 (0x1a), Model: <unknown> (0x2), Stepping: 0x1 Ext. family: 0xb, Ext. model: 0x0, Type: 0x0, Signature: 0x00b00f21 Features: ebx: 0x02100800, ecx: 0xfefa3203, edx: 0x178bfbff Ext. features: eax: 0x00b00f2…
hwThreads uint
4
sockets uint
1
startTime long: millis
289104400880
Example event data values and properties
cores uint
16
cpu string
AMD Unknown x86 (HT) SSE SSE2 SSE3 SSSE3 SSE4.1 SSE4.2 SSE4A AMD64
description string
Brand: AMD EPYC 9V45 96-Core Processor , Vendor: AuthenticAMD Family: Unknown x86 (0x1a), Model: <unknown> (0x2), Stepping: 0x1 Ext. family: 0xb, Ext. model: 0x0, Type: 0x0, Signature: 0x00b00f21 Features: ebx: 0x02100800, ecx: 0xfefa3203, edx: 0x178bfbff Ext. features: eax: 0x00b00f2…
hwThreads uint
4
sockets uint
1
startTime long: millis
11693277935

CPUTimeStampCounter

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

Category: Operating System / Processor

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

Missing in: graalvm_linux_native

Information about the CPU time stamp mechanism / (RD)TSC

Code Context

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

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

    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;

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

Event fields with their types and descriptions
Field Type Description
fastTimeEnabled boolean Fast Time
fastTimeAutoEnabled boolean Trusted Platform
osFrequency long: hertz OS Frequency
fastTimeFrequency long: hertz Fast Time Frequency

Examples 3
Example event data values and properties
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
596493076345
Example event data values and properties
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
24562722972
Example event data values and properties
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
273523021619

CPULoad

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

Category: Operating System / Processor

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

Missing in: graalvm_linux_native

Information about the recent CPU usage of the JVM process

Code Context

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

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

  double t = 0; // total time
  int ret_val = OS_ERR;
  {
    // Can take some time on certain platforms, especially under heavy load.
    // Transition to native to avoid unnecessary stalls for pending safepoint synchronizations.
    ThreadToNativeFromVM transition(JavaThread::current());
    ret_val = JfrOSInterface::cpu_loads_process(&u, &s, &t);
  }
  if (ret_val == OS_ERR) {
    log_debug(jfr, system)( "Unable to generate requestable event CPULoad");
    return;
  }
  if (ret_val == OS_OK) {
    EventCPULoad event;
    event.set_jvmUser((float)u);
    event.set_jvmSystem((float)s);
    event.set_machineTotal((float)t);
    event.commit();
  }
}

TRACE_REQUEST_FUNC(ThreadCPULoad) {
  JfrThreadCPULoadEvent::send_events();
}

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

Event fields with their types and descriptions
Field Type Description
jvmUser float: percentage JVM User
jvmSystem float: percentage JVM System
machineTotal float: percentage Machine Total

Examples 3
Example event data values and properties
jvmSystem float: percentage
0.005
jvmUser float: percentage
0.87
machineTotal float: percentage
0.875
startTime long: millis
290279519025
Example event data values and properties
jvmSystem float: percentage
0.022613065
jvmUser float: percentage
0.3115578
machineTotal float: percentage
0.33417085
startTime long: millis
16556134502
Example event data values and properties
jvmSystem float: percentage
0.011820331
jvmUser float: percentage
0.76122934
machineTotal float: percentage
0.77304965
startTime long: millis
543124000918

ThreadCPULoad

profiling default startTime duration eventThread every chunk 11 17 21 25 27 28 graal vm

Category: Operating System / Processor

Code Context

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

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

int JfrThreadCPULoadEvent::get_processor_count() {
  int cur_processor_count = os::active_processor_count();
  int last_processor_count = _last_active_processor_count;
  _last_active_processor_count = cur_processor_count;

  // If the number of processors decreases, we don't know at what point during
  // the sample interval this happened, so use the largest number to try
  // to avoid percentages above 100%
  return MAX2(cur_processor_count, last_processor_count);
}

// Returns false if the thread has not been scheduled since the last call to updateEvent
// (i.e. the delta for both system and user time is 0 milliseconds)
bool JfrThreadCPULoadEvent::update_event(EventThreadCPULoad& event, JavaThread* thread, jlong cur_wallclock_time, int processor_count) {
  JfrThreadLocal* const tl = thread->jfr_thread_local();

  jlong cur_cpu_time = os::thread_cpu_time(thread, true);
  jlong prev_cpu_time = tl->get_cpu_time();

  jlong prev_wallclock_time = tl->get_wallclock_time();
  tl->set_wallclock_time(cur_wallclock_time);

  // Threshold of 1 ms
  if (cur_cpu_time - prev_cpu_time < 1 * NANOSECS_PER_MILLISEC) {
    return false;

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

  Thread* periodic_thread = Thread::current();
  JfrThreadLocal* const periodic_thread_tl = periodic_thread->jfr_thread_local();
  traceid periodic_thread_id = periodic_thread_tl->thread_id();
  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);
      if (jt != periodic_thread) {
        // Commit reads the thread id from this thread's trace data, so put it there temporarily
        periodic_thread_tl->set_thread_id(JFR_THREAD_ID(jt));
      } else {
        periodic_thread_tl->set_thread_id(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());
  // Restore this thread's thread id
  periodic_thread_tl->set_thread_id(periodic_thread_id);
}

void JfrThreadCPULoadEvent::send_event_for_thread(JavaThread* jt) {
  EventThreadCPULoad event;
  if (event.should_commit()) {
    if (update_event(event, jt, get_wallclock_time(), get_processor_count())) {
      event.commit();
    }
  }
}

src/hotspot/share/jfr/periodic/jfrThreadCPULoadEvent.hpp:

#ifndef SHARE_JFR_PERIODIC_JFRTHREADCPULOADEVENT_HPP
#define SHARE_JFR_PERIODIC_JFRTHREADCPULOADEVENT_HPP

#include "jni.h"
#include "memory/allocation.hpp"

class JavaThread;
class EventThreadCPULoad;

class JfrThreadCPULoadEvent : public AllStatic {
  static int _last_active_processor_count;
 public:
  static jlong get_wallclock_time();
  static int get_processor_count();
  static bool update_event(EventThreadCPULoad& event, JavaThread* thread, jlong cur_wallclock_time, int processor_count);
  static void send_events();
  static void send_event_for_thread(JavaThread* jt);
};

#endif // SHARE_JFR_PERIODIC_JFRTHREADCPULOADEVENT_HPP

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

Event fields with their types and descriptions
Field Type Description
user float: percentage User Mode CPU Load User mode thread CPU load
system float: percentage System Mode CPU Load System mode thread CPU load

Examples 3
Example event data values and properties
startTime long: millis
10431304827
system float: percentage
0.001951323
user float: percentage
0.008450933
Example event data values and properties
startTime long: millis
560748343390
system float: percentage
1.8359202E-5
user float: percentage
0.0
Example event data values and properties
startTime long: millis
275139510852
system float: percentage
3.676519E-5
user float: percentage
0.0

ThreadContextSwitchRate

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

Category: Operating System / Processor

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

Missing in: graalvm_linux_native

Code Context

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

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

    // Can take some time on certain platforms, especially under heavy load.
    // Transition to native to avoid unnecessary stalls for pending safepoint synchronizations.
    ThreadToNativeFromVM transition(JavaThread::current());
    ret_val = JfrOSInterface::context_switch_rate(&rate);
  }
  if (ret_val == OS_ERR) {
    log_debug(jfr, system)( "Unable to generate requestable event ThreadContextSwitchRate");
    return;
  }
  if (ret_val == FUNCTIONALITY_NOT_IMPLEMENTED) {
    return;
  }
  if (ret_val == OS_OK) {
    EventThreadContextSwitchRate event;
    event.set_switchRate((float)rate + 0.0f);
    event.commit();
  }
}

#define SEND_FLAGS_OF_TYPE(eventType, flagType)                   \
  do {                                                            \
    JVMFlag *flag = JVMFlag::flags;                               \
    while (flag->name() != NULL) {                                \
      if (flag->is_ ## flagType()) {                              \
        if (flag->is_unlocked()) {                                \

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

Event fields with their types and descriptions
Field Type Description
switchRate float: hertz Switch Rate Number of context switches per second

Examples 3
Example event data values and properties
startTime long: millis
20601280027
switchRate float: hertz
12982.299
Example event data values and properties
startTime long: millis
598827864889
switchRate float: hertz
3389.7578
Example event data values and properties
startTime long: millis
298815764441
switchRate float: hertz
6872.701

NetworkUtilization

profiling default startTime every chunk 11 17 21 25 27 28

Category: Operating System / Network

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

Missing in: graalvm_linux_native

Code Context

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

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

  static JfrTicks last_sample_instant;
  const JfrTicks cur_time = JfrTicks::now();
  if (cur_time > last_sample_instant) {
    const JfrTickspan interval = cur_time - last_sample_instant;
    for (NetworkInterface *cur = network_interfaces; cur != 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;
    }

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

Event fields with their types and descriptions
Field Type Description
networkInterface NetworkInterfaceName Network Interface Network Interface Name
readRate long: bits-per-second Read Rate Number of incoming bits per second
writeRate long: bits-per-second Write Rate Number of outgoing bits per second

Examples 3
Example event data values and properties
networkInterface NetworkInterfaceName
eth0
readRate long: bits-per-second
5840
startTime long: millis
10418549650
writeRate long: bits-per-second
8384
Example event data values and properties
networkInterface NetworkInterfaceName
enP51047s1
readRate long: bits-per-second
80
startTime long: millis
543124376765
writeRate long: bits-per-second
6784
Example event data values and properties
networkInterface NetworkInterfaceName
eth0
readRate long: bits-per-second
3848
startTime long: millis
282402787326
writeRate long: bits-per-second
5664

PhysicalMemory

profiling default startTime duration every chunk graal vm only

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());

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

Event fields with their types and descriptions
Field Type Description
totalSize ulong: bytes Total Size Total amount of physical memory available to OS
usedSize ulong: bytes Used Size Total amount of physical memory in use

Examples 3
Example event data values and properties
startTime long: millis
270364732239
totalSize ulong: bytes
16766410752
usedSize ulong: bytes
4340596736
Example event data values and properties
startTime long: millis
577069925464
totalSize ulong: bytes
16766414848
usedSize ulong: bytes
6521581568
Example event data values and properties
startTime long: millis
213663298
totalSize ulong: bytes
16766410752
usedSize ulong: bytes
1134215168

ContainerIOUsage

profiling default startTime duration stackTrace 17 21 25 27 28 graal vm

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:

        } catch (IllegalStateException ise) {
            throw ise;
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not add instrumentation for JDK events. " + e.getMessage());
        }
    }

    private static void initializeContainerEvents() {
        containerMetrics = Container.metrics();
        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();

Event configuration settings across JFR profiles
Configuration enabled period
profiling true 30 s
default true 30 s

Event fields with their types and descriptions
Field Type Description
serviceRequests long Block IO Request Count Number of block IO requests to the disk that have been issued by the container
dataTransferred long: bytes Block IO Transfer Number of block IO bytes that have been transferred to/from the disk by the container

ContainerCPUThrottling

profiling default startTime duration stackTrace 17 21 25 27 28 graal vm

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:

@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:

            Logger.log(LogTag.JFR_SYSTEM, LogLevel.INFO, "Retransformed JDK classes");
            jvm.retransformClasses(list.toArray(new Class<?>[list.size()]));
        } catch (IllegalStateException ise) {
            throw ise;
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not add instrumentation for JDK events. " + e.getMessage());
        }
    }

    private static void initializeContainerEvents() {
        containerMetrics = Container.metrics();
        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) {

Event configuration settings across JFR profiles
Configuration enabled period
profiling true 30 s
default true 30 s

Event fields with their types and descriptions
Field Type Description
cpuElapsedSlices long CPU Elapsed Slices Number of time-slice periods that have elapsed if a CPU quota has been setup for the container
cpuThrottledSlices long CPU Throttled Slices Number of time-slice periods that the CPU has been throttled or limited due to exceeding CPU quota
cpuThrottledTime long: nanos CPU Throttled Time Total time duration, in nanoseconds, that the CPU has been throttled or limited due to exceeding CPU quota

ProcessStart

profiling default startTime duration stackTrace 15 17 21 25 27 28

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

Category: Operating System

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

Missing in: graalvm_linux_native

Operating system process started

Code Context

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

src/java.base/share/classes/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()) {
                StringJoiner command = new StringJoiner(" ");
                for (String s: cmdarray) {
                    command.add(s);
                }
                event.directory = dir;
                event.command = command.toString();
                event.pid = process.pid();
                event.commit();
            }
            return process;

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

package jdk.internal.event;

/**
 * Event for the start of an OS procsss
 */

public final class ProcessStartEvent extends Event {
    public long pid;
    public String directory;
    public String command;
}

src/jdk.jfr/share/classes/jdk/jfr/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,
        TLSHandshakeEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

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

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

Event fields with their types and descriptions
Field Type Description
pid long Process Id
directory string Directory
command string Command

Examples 3
Example event data values and properties
command string
rm -rf /home/runner/work/jfrevents/jfrevents/harness-010437-9572483066214688922/apache-spark/chi-square/spark-46aeafd1-97d8-438e-92dd-3cff87f77904
directory string
null
pid long
4557
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
54
lineNumber int
162
method Method
descriptor string
(Ljava/io/File;)V
hidden boolean
false
modifiers int
10
name string
deleteRecursivelyUsingUnixNative
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/network/util/JavaUtils
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/network/util
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
301265968879
Example event data values and properties
command string
java -version
directory string
null
pid long
4663
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
27
lineNumber int
238
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
startProcess
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
750495840
Example event data values and properties
command string
getconf PAGESIZE
directory string
.
pid long
4843
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
61
lineNumber int
1281
method Method
descriptor string
(Lscala/collection/immutable/Seq;Ljava/io/File;Lscala/collection/Map;Z)Ljava/lang/Process;
hidden boolean
false
modifiers int
1
name string
executeCommand
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
org/apache/spark/util/Utils$
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/util
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
545870703086

ContainerCPUUsage

profiling default startTime duration stackTrace 17 21 25 27 28 graal vm

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:

@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:

            list.add(java.lang.Error.class);
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.INFO, "Retransformed JDK classes");
            jvm.retransformClasses(list.toArray(new Class<?>[list.size()]));
        } catch (IllegalStateException ise) {
            throw ise;
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not add instrumentation for JDK events. " + e.getMessage());
        }
    }

    private static void initializeContainerEvents() {
        containerMetrics = Container.metrics();
        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.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.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();

Event configuration settings across JFR profiles
Configuration enabled period
profiling true 30 s
default true 30 s

Event fields with their types and descriptions
Field Type Description
cpuTime long: nanos CPU Time Aggregate time consumed by all tasks in the container
cpuUserTime long: nanos CPU User Time Aggregate user time consumed by all tasks in the container
cpuSystemTime long: nanos CPU System Time Aggregate system time consumed by all tasks in the container

ContainerMemoryUsage

profiling default startTime duration stackTrace 17 21 25 27 28 graal vm

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:

@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:

            jvm.retransformClasses(list.toArray(new Class<?>[list.size()]));
        } catch (IllegalStateException ise) {
            throw ise;
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not add instrumentation for JDK events. " + e.getMessage());
        }
    }

    private static void initializeContainerEvents() {
        containerMetrics = Container.metrics();
        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();

Event configuration settings across JFR profiles
Configuration enabled period
profiling true 30 s
default true 30 s

Event fields with their types and descriptions
Field Type Description
memoryFailCount long Memory Fail Count Number of times that user memory requests in the container have exceeded the memory limit
memoryUsage long: bytes Memory Usage Amount of physical memory, in bytes, that is currently allocated in the current container
swapMemoryUsage long: bytes Memory and Swap Usage Amount of physical memory and swap space, in bytes, that is currently allocated in the current container

ContainerConfiguration

profiling default startTime duration stackTrace 17 21 25 27 28 graal vm

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:

            list.add(java.lang.Throwable.class);
            list.add(java.lang.Error.class);
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.INFO, "Retransformed JDK classes");
            jvm.retransformClasses(list.toArray(new Class<?>[list.size()]));
        } catch (IllegalStateException ise) {
            throw ise;
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not add instrumentation for JDK events. " + e.getMessage());
        }
    }

    private static void initializeContainerEvents() {
        containerMetrics = Container.metrics();
        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.commit();
        }
    }

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

Event fields with their types and descriptions
Field Type Description
containerType string Container Type Container type information
cpuSlicePeriod long: microseconds CPU Slice Period Length of the scheduling period for processes within the container
cpuQuota long: microseconds CPU Quota Total available run-time allowed during each scheduling period for all tasks in the container
cpuShares long CPU Shares Relative weighting of processes with the container used for prioritizing the scheduling of processes across all containers running on a host
effectiveCpuCount long Effective CPU Count Number of effective processors that this container has available to it
memorySoftLimit long: bytes Memory Soft Limit Hint to the operating system that allows groups to specify the minimum required amount of physical memory
memoryLimit long: bytes Memory Limit Maximum amount of physical memory that can be allocated in the container
swapMemoryLimit long: bytes Memory and Swap Limit Maximum amount of physical memory and swap space, in bytes, that can be allocated in the container

Truffle Compiler

org.graalvm.compiler.truffle.CompilerStatistics

startTime duration every 1s graal vm only

Category: Truffle Compiler

Truffe Compiler Statistics

Event fields with their types and descriptions
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

Event fields with their types and descriptions
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

Event fields with their types and descriptions
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.Compilation

startTime duration graal vm only

Category: Truffle Compiler

Truffe Compilation

Event fields with their types and descriptions
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

org.graalvm.compiler.truffle.AssumptionInvalidation

startTime duration stackTrace graal vm only

Category: Truffle Compiler

Truffle Assumption Invalidation

Event fields with their types and descriptions
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

Types

Bytecode

14+

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

Missing in: graalvm_linux_native

Bytecode Instruction

Event fields with their types and descriptions
Field Type Description
bytecode string Instruction

Examples 3

CalleeMethod

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

Missing in: graalvm_linux_native

Event fields with their types and descriptions
Field Type Description
type string Class
name string Method Name
descriptor string Method Descriptor

Examples 3
Example event data values and properties
descriptor string
([BBIIB)[B
name string
ensureCapacityNewCoder
type string
java/lang/AbstractStringBuilder
Example event data values and properties
descriptor string
()Z
name string
booleanValue
type string
java/lang/Boolean
Example event data values and properties
descriptor string
(II)V
name string
checkIndex
type string
java/lang/String

ChunkHeader

14+

Chunk Header

Event fields with their types and descriptions
Field Type Description
payload array byte Payload

Class

Java Class

Event fields with their types and descriptions
Field Type Description
classLoader ClassLoader Class Loader
name Symbol Name
package Package Package
modifiers int Access Modifiers
hidden boolean 15+ Hidden

ClassLoader

Java Class Loader

Event fields with their types and descriptions
Field Type Description
type Class Type
name Symbol Name

CodeBlobType

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

Missing in: graalvm_linux_native

Code Blob Type

Event fields with their types and descriptions
Field Type Description
type string Type

Examples 3
CodeHeap 'non-nmethods'
CodeHeap 'non-profiled nmethods'
CodeHeap 'profiled nmethods'

CompilerPhaseType

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

Missing in: graalvm_linux_native

Compiler Phase Type

Event fields with their types and descriptions
Field Type Description
phase string Phase

Examples 3
After Loop Optimizations
Before Iter GVN
After Iter GVN

CompilerType

14+

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

Missing in: graalvm_linux_native

Compiler Type

Event fields with their types and descriptions
Field Type Description
compiler string Compiler

Examples 3

CopyFailed

Event fields with their types and descriptions
Field Type Description
objectCount ulong Object Count
firstSize ulong: bytes First Failed Object Size
smallestSize ulong: bytes Smallest Failed Object Size
totalSize ulong: bytes Total Object Size

DeoptimizationAction

14+

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

Missing in: graalvm_linux_native

Deoptimization Action

Event fields with their types and descriptions
Field Type Description
action string Action

Examples 3
maybe_recompile
reinterpret
reinterpret

DeoptimizationReason

14+

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

Missing in: graalvm_linux_native

Deoptimization Reason

Event fields with their types and descriptions
Field Type Description
reason string Reason

Examples 3
bimorphic_or_optimized_type_check
class_check
unstable_if

FlagValueOrigin

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

Missing in: graalvm_linux_native

Flag Value Origin

Event fields with their types and descriptions
Field Type Description
origin string Origin

Examples 3

FrameType

Frame type

Event fields with their types and descriptions
Field Type Description
description string Description

Examples 3
Inlined
Native
JIT compiled

G1EvacuationStatistics

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
allocated ulong: bytes Allocated Total memory allocated by PLABs
wasted ulong: bytes Wasted Total memory wasted within PLABs due to alignment or refill
used ulong: bytes Used Total memory occupied by objects within PLABs
undoWaste ulong: bytes Undo Wasted Total memory wasted due to allocation undo within PLABs
regionEndWaste ulong: bytes Region End Wasted Total memory wasted at the end of regions due to refill
regionsRefilled uint Region Refills Number of regions refilled
numPlabsFilled ulong 17+ PLAB Fills Number of PLABs filled
directAllocated ulong: bytes Allocated (direct) Total memory allocated using direct allocation outside of PLABs
numDirectAllocated ulong 17+ Direct allocations Number of direct allocations
failureUsed ulong: bytes Used (failure) Total memory occupied by objects in regions where evacuation failed
failureWaste ulong: bytes Wasted (failure) Total memory left unused in regions where evacuation failed

Examples 3
Example event data values and properties
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1015
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
0
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0
Example event data values and properties
allocated ulong: bytes
96800
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1015
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
1
undoWaste ulong: bytes
0
used ulong: bytes
73304
wasted ulong: bytes
112
Example event data values and properties
allocated ulong: bytes
2097152
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
180
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
1
undoWaste ulong: bytes
0
used ulong: bytes
2028152
wasted ulong: bytes
69000

G1HeapRegionType

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

G1 Heap Region Type

Event fields with their types and descriptions
Field Type Description
type string Type

Examples 3

G1YCType

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

G1 YC Type

Event fields with their types and descriptions
Field Type Description
type string Type

Examples 3

GCCause

GC Cause

Event fields with their types and descriptions
Field Type Description
cause string Cause

Examples 3
G1 Evacuation Pause
System.gc()
Heap Inspection Initiated GC

GCName

GC Name

Event fields with their types and descriptions
Field Type Description
name string Name

Examples 3

GCThresholdUpdater

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

Missing in: graalvm_linux_native

GC Threshold Updater

Event fields with their types and descriptions
Field Type Description
updater string Updater

Examples 3
compute_new_size
compute_new_size
compute_new_size

GCWhen

GC When

Event fields with their types and descriptions
Field Type Description
when string When

Examples 3

InflateCause

Inflation Cause

Event fields with their types and descriptions
Field Type Description
cause string Cause

Examples 3
Monitor Wait
Monitor Wait
Monitor Enter

MetadataType

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

Missing in: graalvm_linux_native

Metadata Type

Event fields with their types and descriptions
Field Type Description
type string Type

Examples 3

MetaspaceObjectType

Metaspace Object Type

Event fields with their types and descriptions
Field Type Description
type string Type

MetaspaceSizes

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

Missing in: graalvm_linux_native

Event fields with their types and descriptions
Field Type Description
committed ulong: bytes Committed Committed memory for this space
used ulong: bytes Used Bytes allocated by objects in the space
reserved ulong: bytes Reserved Reserved memory for this space

Examples 3
Example event data values and properties
committed ulong: bytes
767426560
reserved ulong: bytes
805306368
used ulong: bytes
765550080
Example event data values and properties
committed ulong: bytes
943915008
reserved ulong: bytes
1879048192
used ulong: bytes
940425616
Example event data values and properties
committed ulong: bytes
176488448
reserved ulong: bytes
1073741824
used ulong: bytes
174875536

Method

Java Method

Event fields with their types and descriptions
Field Type Description
type Class Type
name Symbol Name
descriptor Symbol Descriptor
modifiers int Access Modifiers
hidden boolean Hidden

Module

Module

Event fields with their types and descriptions
Field Type Description
name Symbol Name
version Symbol Version
location Symbol Location
classLoader ClassLoader Class Loader

NarrowOopMode

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

Missing in: graalvm_linux_native

Narrow Oop Mode

Event fields with their types and descriptions
Field Type Description
mode string Mode

Examples 3

NetworkInterfaceName

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

Missing in: graalvm_linux_native

Network Interface

Event fields with their types and descriptions
Field Type Description
networkInterface string Network Interface Network Interface Name

Examples 3

ObjectSpace

Appearing in: linux_ParallelGC

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

Event fields with their types and descriptions
Field Type Description
start ulong: address Start Address Start address of the space
end ulong: address End Address End address of the space
used ulong: bytes Used Bytes allocated by objects in the space
size ulong: bytes Size Size of the space

Examples 3
Example event data values and properties
end ulong: address
33927725056
size ulong: bytes
964689920
start ulong: address
32963035136
used ulong: bytes
0
Example event data values and properties
end ulong: address
32247906304
size ulong: bytes
2080374784
start ulong: address
30167531520
used ulong: bytes
257387400
Example event data values and properties
end ulong: address
33988542464
size ulong: bytes
60817408
start ulong: address
33927725056
used ulong: bytes
0

OldObject

Appearing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: linux_ShenandoahGC, linux_ZGC

Old Object

Event fields with their types and descriptions
Field Type Description
address ulong: address Memory Address
type Class Java Class
description string Object Description Object description
referrer Reference Referrer Object Object referencing this object

Examples 3
Example event data values and properties
address ulong: address
30198658240
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/ConcurrentHashMap$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
25.0.4.1
name string
java/util/concurrent
Example event data values and properties
address ulong: address
30172949880
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
Example event data values and properties
address ulong: address
30371924960
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Class
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang

OldObjectArray

Old Object Array

Event fields with their types and descriptions
Field Type Description
size int Array Size Size of array
index int Index Index in the array

OldObjectField

Old Object Field

Event fields with their types and descriptions
Field Type Description
name string Field Name of field
modifiers short Field Modifiers Field modifiers

OldObjectGcRoot

Appearing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: linux_ShenandoahGC, linux_ZGC

GC Root

Event fields with their types and descriptions
Field Type Description
description string Root Description Root information
system OldObjectRootSystem System The subsystem of origin for the root
type OldObjectRootType Type The root type

Examples 3

OldObjectRootSystem

GC Root System

Event fields with their types and descriptions
Field Type Description
system string System

OldObjectRootType

GC Root Type

Event fields with their types and descriptions
Field Type Description
type string Type

Package

Package

Event fields with their types and descriptions
Field Type Description
name Symbol Name
module Module Module
exported boolean Exported

Reference

Appearing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: linux_ShenandoahGC, linux_ZGC

Reference

Event fields with their types and descriptions
Field Type Description
array OldObjectArray Array Information Array or null if it is not an array
field OldObjectField Field Information Field or null if it is an array
object OldObject Object Object holder for this reference
skip int Skip Value The object is this many hops away

Examples 3

ReferenceType

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

Missing in: graalvm_linux_native

Reference Type

Event fields with their types and descriptions
Field Type Description
type string Type

Examples 3
Soft reference
Final reference
Phantom reference

ShenandoahHeapRegionState

Appearing in: linux_ShenandoahGC

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

Shenandoah Heap Region State

Event fields with their types and descriptions
Field Type Description
state string State

Examples 3
Empty Uncommitted
Humongous Continuation
Empty Committed

StackFrame

Event fields with their types and descriptions
Field Type Description
method Method Java Method
lineNumber int Line Number
bytecodeIndex int Bytecode Index
type FrameType Frame Type

Examples 3
Example event data values and properties
bytecodeIndex int
11
lineNumber int
4083
method Method
descriptor string
([DII)[D
hidden boolean
false
modifiers int
9
name string
copyOfRange
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/util/Arrays
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
type FrameType
JIT compiled
Example event data values and properties
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
type FrameType
Native
Example event data values and properties
bytecodeIndex int
35
lineNumber int
134
method Method
descriptor string
()Lbreeze/linalg/DenseVector;
hidden boolean
false
modifiers int
1
name string
copy$mcD$sp
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
breeze/linalg/DenseVector$mcD$sp
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg
type FrameType
Inlined

StackTrace

Stacktrace

Event fields with their types and descriptions
Field Type Description
truncated boolean Truncated
frames array StackFrame struct Stack Frames

Symbol

Symbol

Event fields with their types and descriptions
Field Type Description
string string String

Thread

Thread

Event fields with their types and descriptions
Field Type Description
osName string OS Thread Name
osThreadId long OS Thread Id
javaName string Java Thread Name
javaThreadId long Java Thread Id
group ThreadGroup Java Thread Group

ThreadGroup

Thread Group

Event fields with their types and descriptions
Field Type Description
parent ThreadGroup Parent
name string Name

Examples 3
null
Example event data values and properties
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
Example event data values and properties
name string
system
parent ThreadGroup
null

ThreadState

Java Thread State

Event fields with their types and descriptions
Field Type Description
name string Name

Examples 3
STATE_RUNNABLE
STATE_RUNNABLE
STATE_RUNNABLE

VMOperationType

VM Operation Type

Event fields with their types and descriptions
Field Type Description
type string Type

Examples 3
HeapIterateOperation
FindDeadlocks
HandshakeAllThreads

VirtualSpace

Event fields with their types and descriptions
Field Type Description
start ulong: address Start Address Start address of the virtual space
committedEnd ulong: address Committed End Address End address of the committed memory for the virtual space
committedSize ulong: bytes Committed Size Size of the committed memory for the virtual space
reservedEnd ulong: address Reserved End Address End address of the reserved memory for the virtual space
reservedSize ulong: bytes Reserved Size Size of the reserved memory for the virtual space

Examples 3
Example event data values and properties
committedEnd ulong: address
30203183104
committedSize ulong: bytes
35651584
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
Example event data values and properties
committedEnd ulong: address
31035752448
committedSize ulong: bytes
868220928
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
Example event data values and properties
committedEnd ulong: address
33550237696
committedSize ulong: bytes
3382706176
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520

ZPageTypeType

15+

Appearing in: linux_ZGC

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

Z Page Type

Event fields with their types and descriptions
Field Type Description
type string Type

Examples 1

ZStatisticsCounterType

Appearing in: linux_ZGC

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

Z Statistics Counter

Event fields with their types and descriptions
Field Type Description
counter string Counter

Examples 1
Allocation Rate

ZStatisticsSamplerType

Appearing in: linux_ZGC

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

Z Statistics Sampler

Event fields with their types and descriptions
Field Type Description
sampler string Sampler

Examples 2
Concurrent Roots ClassLoaderDataGraph
JNI Critical Stall

XML Content Types

address

Annotation: jdk.jfr.MemoryAddress

Examples 3
94850179351856
30355835520
32312918016

bits-per-second

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

Missing in: graalvm_linux_native

Annotation: jdk.jfr.DataAmount(BITS), jdk.jfr.Frequency

Examples 3

bytes

Annotation: jdk.jfr.DataAmount(BYTES)

Examples 3

bytes-per-second

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Annotation: jdk.jfr.DataAmount(BYTES), jdk.jfr.Frequency

Examples 3
3.6571742992201753E9
3.077763095773205E8
2.691982589276779E8

certificateId

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Annotation: jdk.jfr.events.CertificateId

Examples 3
3649430051
288990878
2389201834

epochmillis

Annotation: jdk.jfr.Timestamp(MILLISECONDS_SINCE_EPOCH)

Examples 3
1791075877084
-9223372036854775808
1791075877311

hertz

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

Missing in: graalvm_linux_native

Annotation: jdk.jfr.Frequency

Examples 3

microseconds

17+

Annotation: jdk.jfr.Timespan(MICROSECONDS)

millis

Annotation: jdk.jfr.Timespan(MILLISECONDS)

Examples 3
267232203049
266694457288
268143485327

nanos

Annotation: jdk.jfr.Timespan(NANOSECONDS)

Examples 3

percentage

Annotation: jdk.jfr.Percentage

Examples 3

tickspan

Annotation: jdk.jfr.Timespan(TICKS)

Examples 3

tickstamp

Annotation: jdk.jfr.Timestamp(TICKS)

XML Types

Class

Property Value
Parameter Type const Klass*
Field Type const Klass*
Java Type java.lang.Class
Examples 3
Example event data values and properties
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionObject
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent/locks
null
null

ClassLoader

Property Value
Parameter Type const ClassLoaderData*
Field Type const ClassLoaderData*
Examples 3
Example event data values and properties
name string
bootstrap
type Class
null
Example event data values and properties
name string
bootstrap
type Class
null
Example event data values and properties
name string
bootstrap
type Class
null

Method

Property Value
Parameter Type const Method*
Field Type const Method*
Examples 3
Example event data values and properties
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
Example event data values and properties
descriptor string
()Lbreeze/linalg/DenseVector;
hidden boolean
false
modifiers int
1
name string
copy$mcD$sp
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
breeze/linalg/DenseVector$mcD$sp
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg
Example event data values and properties
descriptor string
([DII)[D
hidden boolean
false
modifiers int
9
name string
copyOfRange
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/util/Arrays
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util

Module

Property Value
Parameter Type const ModuleEntry*
Field Type const ModuleEntry*
Examples 3
Example event data values and properties
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
Example event data values and properties
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
Example event data values and properties
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1

Package

Property Value
Parameter Type const PackageEntry*
Field Type const PackageEntry*
Examples 3
Example event data values and properties
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
Example event data values and properties
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent/locks
Example event data values and properties
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc

StackTrace

15+

Property Value
Parameter Type u8
Field Type u8
Java Type jdk.types.StackTrace
Examples 3
Example event data values and properties
frames StackFrame
bytecodeIndex int
11
lineNumber int
4083
method Method
descriptor string
([DII)[D
hidden boolean
false
modifiers int
9
name string
copyOfRange
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/util/Arrays
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
type FrameType
JIT compiled
…
truncated boolean
false
Example event data values and properties
frames StackFrame
bytecodeIndex int
35
lineNumber int
134
method Method
descriptor string
()Lbreeze/linalg/DenseVector;
hidden boolean
false
modifiers int
1
name string
copy$mcD$sp
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
breeze/linalg/DenseVector$mcD$sp
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg
type FrameType
Inlined
…
truncated boolean
false
Example event data values and properties
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
type FrameType
Native
…
truncated boolean
false

Thread

Property Value
Parameter Type u8
Field Type u8
Java Type java.lang.Thread
Examples 3
null
Example event data values and properties
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
task-result-getter-3
javaThreadId long
1745
osName string
task-result-getter-3
osThreadId long
4643
virtual boolean
false
Example event data values and properties
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 3.0 in stage 48.0 (TID 189)
javaThreadId long
1678
osName string
Executor task launch worker for task 3.0 in stage 48.0 (TID 189)
osThreadId long
4208
virtual boolean
false

Ticks

unsigned

Appearing in: graalvm_linux_G1GC, graalvm_linux_native, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: linux_ShenandoahGC, linux_ZGC

Property Value
Parameter Type const Ticks&
Field Type Ticks
Java Type long
Content Type tickstamp
Examples 3
25246409681
20832544279
295330495168

Tickspan

unsigned

Property Value
Parameter Type const Tickspan&
Field Type Tickspan
Java Type long
Content Type tickspan

boolean

Property Value
Parameter Type bool
Field Type bool
Java Type boolean
Examples 3

byte

Property Value
Parameter Type s1
Field Type s1
Java Type byte

char

Property Value
Parameter Type char
Field Type char
Java Type char

double

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

Missing in: graalvm_linux_native

Property Value
Parameter Type double
Field Type double
Java Type double
Examples 3

float

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

Missing in: graalvm_linux_native

Property Value
Parameter Type float
Field Type float
Java Type float
Examples 3
2.1938856
4.8131332
4.802841

int

Property Value
Parameter Type s4
Field Type s4
Java Type int
Examples 3

long

Property Value
Parameter Type s8
Field Type s8
Java Type long
Examples 3

short

Property Value
Parameter Type s2
Field Type s2
Java Type short

string

Property Value
Parameter Type const char*
Field Type const char*
Java Type java.lang.String
Examples 3
java/util/concurrent/locks
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionObject
bootstrap

ubyte

unsigned

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

Missing in: graalvm_linux_native

Property Value
Parameter Type u1
Field Type u1
Java Type byte
Examples 3

uint

unsigned

Property Value
Parameter Type unsigned
Field Type unsigned
Java Type int
Examples 3

ulong

unsigned

Property Value
Parameter Type u8
Field Type u8
Java Type long
Examples 3

ushort

unsigned

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

Missing in: graalvm_linux_native

Property Value
Parameter Type u2
Field Type u2
Java Type short
Examples 3