Introduction

This page is a complete reference of Java Flight Recorder (JFR) events for OpenJDK 13 (jdk-13.0.14+5, permalink, 20-September-2026). JFR events are the foundation of JVM profiling and observability — they capture runtime data such as garbage collection pauses, CPU load, thread activity, class loading, compilations, and more. The events listed here are collected from the JFR event configuration and the OpenJDK source code. Visit the jfreventcollector repository for more information. This is also where you can contribute additional event descriptions, if you don't want to contribute them directly to the OpenJDK. The site generator lives on GitHub, too.

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

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

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

Flight Recorder

DumpReason

default profiling startTime 11 17 21 25 27 28

Category: Flight Recorder

Who requested the recording and why

Code Context

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

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

  if (exception_handler) {
    // we are crashing
    if (thread->is_Watcher_thread()) {
      // The Watcher thread runs the periodic thread sampling task.
      // If it has crashed, it is likely that another thread is
      // left in a suspended state. This would mean the system
      // will not be able to ever move to a safepoint. We try
      // to avoid issuing safepoint operations when attempting
      // an emergency dump, but a safepoint might be already pending.
      return;
    }
    prepare_for_emergency_dump(thread);
  }
  EventDumpReason event;
  if (event.should_commit()) {
    event.set_reason(exception_handler ? "Crash" : "Out of Memory");
    event.set_recordingId(-1);
    event.commit();
  }
  if (!exception_handler) {
    // OOM
    LeakProfiler::emit_events(max_jlong, false);
  }
  const int messages = MSGBIT(MSG_VM_ERROR);
  ResourceMark rm(thread);

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

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

DataLoss

default profiling startTime 11 17 21 25 27 28

Category: Flight Recorder

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

Code Context

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

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

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

static void write_data_loss_event(JfrBuffer* buffer, u8 unflushed_size, Thread* thread) {
  assert(buffer != 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.write<u8>(EventDataLoss::eventId);
    writer.write(JfrTicks::now());
    writer.write(unflushed_size);
    writer.write(total_data_loss);
  }
}

static void write_data_loss(BufferPtr buffer, Thread* thread) {
  assert(buffer != NULL, "invariant");
  const size_t unflushed_size = buffer->unflushed_size();
  buffer->concurrent_reinitialization();
  if (unflushed_size == 0) {

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

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

ActiveSetting

default profiling startTime duration stackTrace 11 17 21 25 27 28

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

Category: Flight Recorder

Code Context

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

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

    private RepositoryChunk currentChunk;

    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);
        timer = createTimer();
    }


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

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

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

    void writeActiveSettingEvent() {
        if (!type.isRegistered()) {
            return;
        }
        for (Map.Entry<String, Control> entry : eventControls.entrySet()) {
            Control c = entry.getValue();
            if (Utils.isSettingVisible(c, type.hasEventHook())) {
                String value = c.getLastValue();
                if (value == null) {
                    value = c.getDefaultValue();
                }
                ActiveSettingEvent ase = new ActiveSettingEvent();
                ase.id = type.getId();
                ase.name = entry.getKey();
                ase.value = value;
                ase.commit();
            }
        }
    }

    public Set<Entry<String, Control>> getEntries() {
        return eventControls.entrySet();
    }

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;
}

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

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

Examples 3
Example event data values and properties
id long
132
name string
enabled
startTime long: millis
447752338153
value string
true
Example event data values and properties
id long
1918
name string
enabled
startTime long: millis
453048059860
value string
true
Example event data values and properties
id long
153
name string
enabled
startTime long: millis
361737433
value string
true

ActiveRecording

default profiling startTime duration stackTrace 11 17 21 25 27 28

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

Category: Flight Recorder

Code Context

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

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

    private long recordingCounter = 0;
    private RepositoryChunk currentChunk;

    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);
        timer = createTimer();
    }


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

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

        chunk.finish(time);
        for (PlatformRecording r : getRecordings()) {
            if (r != ignoreMe && r.getState() == RecordingState.RUNNING) {
                r.appendChunk(chunk);
            }
        }
    }

    private void writeMetaEvents() {

        if (activeRecordingEvent.isEnabled()) {
            for (PlatformRecording r : getRecordings()) {
                if (r.getState() == RecordingState.RUNNING && r.shouldWriteMetadataEvent()) {
                    ActiveRecordingEvent event = new ActiveRecordingEvent();
                    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();
                    event.maxSize = size == null ? Long.MAX_VALUE : size;
                    Instant start = r.getStartTime();

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

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 {

    @Label("Id")
    public long id;

    @Label("Name")
    public String name;

    @Label("Destination")
    public String destination;

    @Label("Max Age")

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

Event fields with their types and descriptions
Field Type Description
id long Id
name string Name
destination string Destination
maxAge long: millis Max Age
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
id long
1
maxAge long: millis
9223372036854775807
maxSize long: bytes
0
name string
1
recordingDuration long: millis
27000
recordingStart long: epochmillis
1788871963460
startTime long: millis
361737433
Example event data values and properties
destination string
/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseParallelGC.jfr
id long
1
maxAge long: millis
9223372036854775807
maxSize long: bytes
262144000
name string
1
recordingDuration long: millis
9223372036854775807
recordingStart long: epochmillis
1789259151646
startTime long: millis
451438478123
Example event data values and properties
destination string
/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseG1GC.jfr
id long
1
maxAge long: millis
9223372036854775807
maxSize long: bytes
262144000
name string
1
recordingDuration long: millis
9223372036854775807
recordingStart long: epochmillis
1788871449508
startTime long: millis
464046440606

JVM

JVMInformation

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

Category: Java Virtual Machine

Description of JVM and the Java application

Code Context

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

src/hotspot/share/jfr/periodic/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
default true beginChunk
profiling true beginChunk

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

Examples 3
Example event data values and properties
javaArguments string
/home/runner/work/jfrevents/jfrevents/.cache/jfr_sample_app.jar
jvmArguments string
--add-exports=java.base/jdk.internal.vm.annotation=ALL-UNNAMED -Djdk.attach.allowAttachSelf=true -XX:+UnlockDiagnosticVMOptions -XX:DiagnoseSyncOnValueBasedClasses=2 -XX:NativeMemoryTracking=summary -XX:StartFlightRecording=filename=/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseG1GC_even…
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1788871963118
jvmVersion string
OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS) for linux-amd64 JRE (25.0.4.1+1-LTS), built on 2026-08-14T07:36:00Z with gcc 14.2.0
pid long
5013
startTime long: millis
364471320
Example event data values and properties
javaArguments string
/home/runner/work/jfrevents/jfrevents/.cache/renaissance.jar -t 5 -r 1 all
jvmArguments string
-XX:StartFlightRecording=filename=/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseParallelGC.jfr,settings=/home/runner/work/jfrevents/jfrevents/.cache/jfc.jfc -XX:+UseParallelGC
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1789259151398
jvmVersion string
OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS) for linux-amd64 JRE (25.0.4.1+1-LTS), built on 2026-08-14T07:36:00Z with gcc 14.2.0
pid long
2150
startTime long: millis
451440035149
Example event data values and properties
javaArguments string
/home/runner/work/jfrevents/jfrevents/.cache/renaissance.jar -t 5 -r 1 all
jvmArguments string
-XX:StartFlightRecording=filename=/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseG1GC.jfr,settings=/home/runner/work/jfrevents/jfrevents/.cache/jfc.jfc -XX:+UseG1GC
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1788871449128
jvmVersion string
OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS) for linux-amd64 JRE (25.0.4.1+1-LTS), built on 2026-08-14T07:36:00Z with gcc 14.2.0
pid long
2534
startTime long: millis
477043367481

InitialSystemProperty

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

Category: Java Virtual Machine

System Property at JVM start

Code Context

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

src/hotspot/share/jfr/periodic/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
default true beginChunk
profiling true beginChunk

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

Examples 3
Example event data values and properties
key string
java.vm.version
startTime long: millis
462141525582
value string
25.0.4.1+1-LTS
Example event data values and properties
key string
jdk.debug
startTime long: millis
449445022271
value string
release
Example event data values and properties
key string
java.vm.vendor
startTime long: millis
15623065214
value string
SAP SE

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:

          SystemDictionary_lock->wait();
        } else {
          double_lock_wait(lockObject, THREAD);
        }
      } else {
        // If not in SD and not in PH, other thread's load must have failed
        super_load_in_progress = false;
      }
    }
  }
  return NULL;
}

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


// Be careful when modifying this code: once you have run
// placeholders()->find_and_add(PlaceholderTable::LOAD_INSTANCE),
// you need to find_and_remove it before returning.
// So be careful to not exit with a CHECK_ macro betweeen these calls.
//
// name must be in the form of "java/lang/Object" -- cannot be "Ljava/lang/Object;"
InstanceKlass* SystemDictionary::resolve_instance_class_or_null(Symbol* name,
                                                                Handle class_loader,
                                                                Handle protection_domain,
                                                                TRAPS) {
  assert(name != NULL && !FieldType::is_array(name) &&
         !FieldType::is_obj(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 d_hash = dictionary->compute_hash(name);

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

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

// Note: this method is much like resolve_from_stream, but
// does not publish the classes via the SystemDictionary.
// Handles unsafe_DefineAnonymousClass and redefineclasses
// RedefinedClasses do not add to the class hierarchy
InstanceKlass* SystemDictionary::parse_stream(Symbol* class_name,
                                              Handle class_loader,
                                              Handle protection_domain,
                                              ClassFileStream* st,
                                              const InstanceKlass* unsafe_anonymous_host,
                                              GrowableArray<Handle>* cp_patches,
                                              TRAPS) {

  EventClassLoad class_load_start_event;

  ClassLoaderData* loader_data;
  if (unsafe_anonymous_host != NULL) {
    // Create a new CLD for an unsafe anonymous class, that uses the same class loader
    // as the unsafe_anonymous_host
    guarantee(oopDesc::equals(unsafe_anonymous_host->class_loader(), class_loader()), "should be the same");
    loader_data = ClassLoaderData::unsafe_anonymous_class_loader_data(class_loader);
  } else {
    loader_data = ClassLoaderData::class_loader_data(class_loader());
  }

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

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

Examples 3
Example event data values and properties
definingClassLoader ClassLoader
name string
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
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
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/String;)Ljava/lang/Class;
hidden boolean
false
modifiers int
266
name string
findBootstrapClass
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
386628828
Example event data values and properties
definingClassLoader ClassLoader
name string
bootstrap
type Class
null
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
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/nio/file/Paths
package Package
exported boolean
true
module Module
classLoader ClassLoader
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/file
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
8
lineNumber int
56
method Method
descriptor string
(Lorg/apache/spark/executor/ProcfsMetricsGetter;)Z
hidden boolean
false
modifiers int
4121
name string
$anonfun$isProcfsAvailable$1
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/executor/ProcfsMetricsGetter
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/executor
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
459090359292
Example event data values and properties
definingClassLoader ClassLoader
null
initiatingClassLoader ClassLoader
null
loadedClass Class
classLoader ClassLoader
null
hidden boolean
true
modifiers int
16
name string
java.lang.invoke.LambdaForm$MH/0x000000008daec000
package Package
exported boolean
true
module Module
classLoader ClassLoader
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
457487222153

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:

      // For user defined Java class loaders, check that the name returned is
      // the same as that requested.  This check is done for the bootstrap
      // loader when parsing the class file.
      if (class_name == k->name()) {
        return k;
      }
    }
    // Class is not found or has the wrong name, return NULL
    return NULL;
  }
}

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, TRAPS) {

  HandleMark hm(THREAD);
  ClassLoaderData* loader_data = k->class_loader_data();

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

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

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/rpc/netty/OnStop$
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
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
475237358757
Example event data values and properties
definedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1537
name string
java/security/SecureRandomParameters
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/security
definingClassLoader ClassLoader
name string
bootstrap
type Class
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
101
lineNumber int
1419
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
<clinit>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/security/Provider
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/security
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
389413580
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
480341850443

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 (DumpSharedSpaces || DynamicDumpSharedSpaces) {
    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
}

void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
  // Clean up C heap
  ik->release_C_heap_structures();
  ik->constants()->release_C_heap_structures();
}

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

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

Examples 3
Example event data values and properties
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
0
name string
jfr_sample/Main$2
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
startTime long: millis
2265629468
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/Unloadable2179031201249
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
500050922289
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.core.Definitions$$Lambda/0x000000008e278000
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
dotty/tools/dotc/core
Example event data values and properties
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
startTime long: millis
492449360062
unloadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
true
modifiers int
4112
name string
dotty.tools.backend.jvm.BCodeSkelBuilder$PlainSkelBuilder$$Lambda/0x0000000083283400
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/backend/jvm

JVM: Code Cache

CodeCacheFull

default profiling startTime eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Code Cache

Code Context

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

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

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

    if (heap->full_count() == 0) {
      if (PrintCodeHeapAnalytics) {
        CompileBroker::print_heapinfo(tty, "all", 4096); // details, may be a lot!
      }
    }
  }

  heap->report_full();

  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.commit();

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

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

CodeCacheStatistics

default profiling startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Code Cache

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

Missing in: graalvm_linux_native

Code Context

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

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

TRACE_REQUEST_FUNC(CompilerConfiguration) {
  EventCompilerConfiguration event;
  event.set_threadCount(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
default true everyChunk
profiling true everyChunk

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

Examples 3
Example event data values and properties
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'non-profiled nmethods'
entryCount int
8093
fullCount int
0
methodCount int
8093
reservedTopAddress ulong: address
140618089103360
startAddress ulong: address
140617965371392
startTime long: millis
454660695616
unallocatedCapacity ulong: bytes
112570496
Example event data values and properties
adaptorCount int
479
codeBlobType CodeBlobType
CodeHeap 'non-nmethods'
entryCount int
575
fullCount int
0
methodCount int
0
reservedTopAddress ulong: address
140366911111168
startAddress ulong: address
140366904819712
startTime long: millis
25441211109
unallocatedCapacity ulong: bytes
4726528
Example event data values and properties
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'non-profiled nmethods'
entryCount int
10066
fullCount int
0
methodCount int
10066
reservedTopAddress ulong: address
140168325496832
startAddress ulong: address
140168201764864
startTime long: millis
487374136378
unallocatedCapacity ulong: bytes
110459392

CodeCacheConfiguration

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

Category: Java Virtual Machine / Code Cache

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

Missing in: graalvm_linux_native

Code Context

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

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

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

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

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

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

Examples 3
Example event data values and properties
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
6291456
nonProfiledSize ulong: bytes
123731968
profiledSize ulong: bytes
123731968
reservedSize ulong: bytes
253755392
reservedTopAddress ulong: address
140168325496832
startAddress ulong: address
140168071741440
startTime long: millis
454119616227
Example event data values and properties
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
6291456
nonProfiledSize ulong: bytes
123731968
profiledSize ulong: bytes
123731968
reservedSize ulong: bytes
253755392
reservedTopAddress ulong: address
140618089103360
startAddress ulong: address
140617835347968
startTime long: millis
496741430432
Example event data values and properties
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
6291456
nonProfiledSize ulong: bytes
123731968
profiledSize ulong: bytes
123731968
reservedSize ulong: bytes
253755392
reservedTopAddress ulong: address
140367034843136
startAddress ulong: address
140366781087744
startTime long: millis
364948715

JVM: Code Sweeper

SweepCodeCache

default profiling 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:

  if (_should_sweep) {
    _bytes_changed = 0;
  }

  if (forced) {
    // Notify requester that forced sweep finished
    assert(_force_sweep, "Should be a forced sweep");
    MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
    _force_sweep = false;
    CodeCache_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:

  const Ticks sweep_end_counter = Ticks::now();
  const Tickspan sweep_time = sweep_end_counter - sweep_start_counter;
  {
    MutexLocker mu(NMethodSweeperStats_lock, Mutex::_no_safepoint_check_flag);
    _total_time_sweeping  += sweep_time;
    _total_time_this_sweep += sweep_time;
    _peak_sweep_fraction_time = MAX2(sweep_time, _peak_sweep_fraction_time);
    _total_flushed_size += freed_memory;
    _total_nof_methods_reclaimed += flushed_count;
    _total_nof_c2_methods_reclaimed += flushed_c2_count;
    _peak_sweep_time = MAX2(_peak_sweep_time, _total_time_this_sweep);
  }

  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);
  }

#ifdef ASSERT
  if(PrintMethodFlushing) {
    tty->print_cr("### sweeper:      sweep time(" JLONG_FORMAT "): ", sweep_time.value());
  }
#endif

  Log(codecache, sweep) log;

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

default profiling 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
default true everyChunk
profiling 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

default profiling 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.commit();
}


TRACE_REQUEST_FUNC(ShenandoahHeapRegionInformation) {
#if INCLUDE_SHENANDOAHGC
  if (UseShenandoahGC) {
    VM_ShenandoahSendHeapRegionInfoEvents op;
    VMThread::execute(&op);

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

Event fields with their types and descriptions
Field Type Description
sweeperEnabled boolean Code Sweeper Enabled
flushingEnabled boolean Code Cache Flushing Enabled

JVM: Compiler

Compilation

default profiling startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Compiler

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

Missing in: graalvm_linux_native

Code Context

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

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

  } 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(event != NULL, "invariant");
  assert(event->should_commit(), "invariant");
  event->set_method(task->method());
  event->set_compileId(task->compile_id());
  event->set_compileLevel(task->comp_level());
  event->set_succeded(task->is_success());
  event->set_isOsr(task->osr_bci() != CompileBroker::standard_entry_bci);
  event->set_codeSize((task->code() == NULL) ? 0 : task->code()->total_size());
  event->set_inlinedBytes(task->num_inlined_bytecodes());
  event->commit();
}

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

  const char* retry_message = NULL;

  int system_dictionary_modification_counter;
  {
    MutexLocker locker(Compile_lock, thread);
    system_dictionary_modification_counter = SystemDictionary::number_of_modifications();
  }

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

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

    // Skip redefined methods
    if (target_handle->is_old()) {
      failure_reason = "redefined method";
      retry_message = "not retryable";
      compilable = ciEnv::MethodCompilable_never;
    } else {
      JVMCICompileState compile_state(task, system_dictionary_modification_counter);
      JVMCIEnv env(thread, &compile_state, __FILE__, __LINE__);
      methodHandle method(thread, target_handle);
      env.runtime()->compile_method(&env, jvmci, method, osr_bci);

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

    assert(thread->env() == &ci_env, "set by ci_env");
    // The thread-env() field is cleared in ~CompileTaskWrapper.

    // Cache Jvmti state
    ci_env.cache_jvmti_state();

    // 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", !TieredCompilation);
    } else {
      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, directive);

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

 * Service-provider class for logging compiler related events.
 */
public interface EventProvider {

    /**
     * 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.
     */
    public interface InstantEvent {
        /**
         * Commits the event.

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

    public interface TimedEvent extends InstantEvent {
        /**
         * Starts the timing for this event.
         */
        void begin();

        /**
         * 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);

        void setIsOsr(boolean isOsr);

        void setCodeSize(int codeSize);

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

package jdk.vm.ci.hotspot;

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

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

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

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

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

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

Event fields with their types and descriptions
Field Type Description
method Method Java Method
compileId uint Compilation Identifier
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
1120
compileId uint
1396
compileLevel ushort
3
inlinedBytes ulong: bytes
8
isOsr boolean
false
method Method
descriptor string
(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
false
modifiers int
33
name string
put
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/Properties
package Package
exported boolean
true
module Module
classLoader ClassLoader
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
397229098
succeded boolean
true
Example event data values and properties
codeSize ulong: bytes
312
compileId uint
94105
compileLevel ushort
1
inlinedBytes ulong: bytes
0
isOsr boolean
false
method Method
descriptor string
([Ljava/lang/Object;)V
hidden boolean
false
modifiers int
1
name string
array_$eq
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
scala/collection/mutable/ArrayDeque
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection/mutable
startTime long: millis
453405745842
succeded boolean
true
Example event data values and properties
codeSize ulong: bytes
1608
compileId uint
92792
compileLevel ushort
3
inlinedBytes ulong: bytes
30
isOsr boolean
false
method Method
descriptor string
()Ljava/lang/Object;
hidden boolean
false
modifiers int
1
name string
next
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
scala/collection/Iterator$$anon$22
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
startTime long: millis
448060891194
succeded boolean
true

CompilerPhase

default profiling startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Compiler

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

Missing in: graalvm_linux_native

Code Context

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

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

    C->_latest_stage_start_counter.stamp();
  }

  bool should_print(int level = 1) {
#ifndef PRODUCT
    return (_printer && _printer->should_print(level));
#else
    return false;
#endif
  }

  void print_method(CompilerPhaseType cpt, int level = 1, int idx = 0) {
    EventCompilerPhase event;
    if (event.should_commit()) {
      event.set_starttime(C->_latest_stage_start_counter);
      event.set_phase((u1) cpt);
      event.set_compileId(C->_compile_id);
      event.set_phaseLevel(level);
      event.commit();
    }

#ifndef PRODUCT
    if (should_print(level)) {
      char output[1024];
      if (idx != 0) {
        sprintf(output, "%s:%d", CompilerPhaseTypeHelper::to_string(cpt), idx);
      } else {
        sprintf(output, "%s", CompilerPhaseTypeHelper::to_string(cpt));
      }
      _printer->print_method(output, level);
    }
#endif
    C->_latest_stage_start_counter.stamp();
  }

  void end_method(int level = 1) {
    EventCompilerPhase event;
    if (event.should_commit()) {
      event.set_starttime(C->_latest_stage_start_counter);
      event.set_phase((u1) PHASE_END);
      event.set_compileId(C->_compile_id);
      event.set_phaseLevel(level);
      event.commit();
    }
#ifndef PRODUCT
    if (_printer && _printer->should_print(level)) {
      _printer->end_method();
    }

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

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

Examples 3
Example event data values and properties
compileId uint
94077
phase CompilerPhaseType
After Iter GVN
phaseLevel ushort
3
startTime long: millis
453348166020
Example event data values and properties
compileId uint
92746
phase CompilerPhaseType
After CountedLoop
phaseLevel ushort
3
startTime long: millis
447964770863
Example event data values and properties
compileId uint
1362
phase CompilerPhaseType
After Iter GVN
phaseLevel ushort
3
startTime long: millis
363791462

CompilationFailure

profiling startTime eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Compiler

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

Missing in: graalvm_linux_native

Code Context

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

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

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

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

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

Examples 3
Example event data values and properties
compileId uint
103392
failureMessage string
out of virtual registers in linear scan
startTime long: millis
486684889175
Example event data values and properties
compileId uint
2606
failureMessage string
Jvmti state change invalidated dependencies
startTime long: millis
1482637230
Example event data values and properties
compileId uint
103164
failureMessage string
retry without subsuming loads
startTime long: millis
491376122638

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

Code Context

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

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

  Value index = args->at(1);
  if (is_store) {
    Value value = args->at(2);
    Instruction* store = append(new StoreIndexed(array, index, NULL, T_CHAR, value, state_before, false, true));
    store->set_flag(Instruction::NeedsRangeCheckFlag, false);
    _memory->store_value(value);
  } else {
    Instruction* load = append(new LoadIndexed(array, index, NULL, T_CHAR, state_before, true));
    load->set_flag(Instruction::NeedsRangeCheckFlag, false);
    push(load->type(), load);
  }
}

static void post_inlining_event(EventCompilerInlining* event,
                                int compile_id,
                                const char* msg,
                                bool success,
                                int bci,
                                ciMethod* caller,
                                ciMethod* callee) {
  assert(caller != NULL, "invariant");
  assert(callee != NULL, "invariant");
  assert(event != NULL, "invariant");
  assert(event->should_commit(), "invariant");
  JfrStructCalleeMethod callee_struct;

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

  event->commit();
}

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()) {
    post_inlining_event(&event, compilation()->env()->task()->compile_id(), msg, success, bci(), method(), callee);
  }

  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/opto/bytecodeInfo.cpp:

const char* InlineTree::check_can_parse(ciMethod* callee) {
  // Certain methods cannot be parsed at all:
  if ( callee->is_native())                     return "native method";
  if ( callee->is_abstract())                   return "abstract method";
  if (!callee->has_balanced_monitors())         return "not compilable (unbalanced monitors)";
  if ( callee->get_flow_analysis()->failing())  return "not compilable (flow analysis failed)";
  if (!callee->can_be_parsed())                 return "cannot be parsed";
  return NULL;
}

static void post_inlining_event(int compile_id,const char* msg, bool success, int bci, ciMethod* caller, ciMethod* callee) {
  assert(caller != NULL, "invariant");
  assert(callee != NULL, "invariant");
  EventCompilerInlining event;
  if (event.should_commit()) {
    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());
    event.set_compileId(compile_id);
    event.set_message(msg);
    event.set_succeeded(success);
    event.set_bci(bci);
    event.set_caller(caller->get_Method());
    event.set_callee(callee_struct);

Event configuration settings across JFR profiles
Configuration enabled
default false
profiling 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 Byte Code Index

Examples 3
Example event data values and properties
bci int
12
callee CalleeMethod
descriptor string
(Ljava/lang/Class;)Ljava/lang/Object;
name string
allocateInstance
type string
jdk/internal/misc/Unsafe
caller Method
descriptor string
(Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
false
modifiers int
8
name string
allocateInstance
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/invoke/DirectMethodHandle
package Package
exported boolean
true
module Module
classLoader ClassLoader
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
compileId uint
92733
message string
native method
startTime long: millis
447748322582
succeeded boolean
false
Example event data values and properties
bci int
11
callee CalleeMethod
descriptor string
()V
name string
<init>
type string
java/lang/Object
caller Method
descriptor string
(JZ)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
9
name string
org/apache/spark/storage/BlockManagerMessages$RemoveBroadcast
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/storage
compileId uint
94076
message string
inline
startTime long: millis
453289888965
succeeded boolean
true
Example event data values and properties
bci int
2
callee CalleeMethod
descriptor string
(Ljdk/jfr/internal/LogTag;Ljdk/jfr/internal/LogLevel;)Z
name string
shouldLog
type string
jdk/jfr/internal/Logger
caller Method
descriptor string
(Ljdk/jfr/internal/LogTag;Ljdk/jfr/internal/LogLevel;Ljava/lang/String;)V
hidden boolean
false
modifiers int
9
name string
log
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/jfr/internal/Logger
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
compileId uint
1340
message string
inline
startTime long: millis
361767653
succeeded boolean
true

CompilerStatistics

default profiling startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Compiler

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

Missing in: graalvm_linux_native

Code Context

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

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

TRACE_REQUEST_FUNC(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
default true 1000 ms
profiling true 1000 ms

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

Examples 3
Example event data values and properties
bailoutCount int
4
compileCount int
2731
invalidatedCount int
0
nmethodCodeSize ulong: bytes
3633784
nmethodsSize ulong: bytes
4904384
osrBytesCompiled ulong: bytes
0
osrCompileCount int
22
peakTimeSpent long: millis
190
standardBytesCompiled ulong: bytes
0
standardCompileCount int
2709
startTime long: millis
5447552559
totalTimeSpent long: millis
2670
Example event data values and properties
bailoutCount int
9
compileCount int
98418
invalidatedCount int
0
nmethodCodeSize ulong: bytes
154429440
nmethodsSize ulong: bytes
216922448
osrBytesCompiled ulong: bytes
0
osrCompileCount int
1058
peakTimeSpent long: millis
8163
standardBytesCompiled ulong: bytes
0
standardCompileCount int
97360
startTime long: millis
487917753159
totalTimeSpent long: millis
449364
Example event data values and properties
bailoutCount int
11
compileCount int
112039
invalidatedCount int
0
nmethodCodeSize ulong: bytes
169287224
nmethodsSize ulong: bytes
243497144
osrBytesCompiled ulong: bytes
0
osrCompileCount int
1070
peakTimeSpent long: millis
27428
standardBytesCompiled ulong: bytes
0
standardCompileCount int
110969
startTime long: millis
494788917881
totalTimeSpent long: millis
810893

CompilerConfiguration

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

Category: Java Virtual Machine / Compiler

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

Missing in: graalvm_linux_native

Code Context

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

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

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

TRACE_REQUEST_FUNC(CompilerConfiguration) {
  EventCompilerConfiguration event;
  event.set_threadCount(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
default true beginChunk
profiling 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
23227711021
threadCount int
3
tieredCompilation boolean
true
Example event data values and properties
startTime long: millis
449445142582
threadCount int
3
tieredCompilation boolean
true
Example event data values and properties
startTime long: millis
477043561685
threadCount int
3
tieredCompilation boolean
true

JVM: Flag

IntFlagChanged

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

  if (!result->is_int()) return JVMFlag::WRONG_FORMAT;
  *value = result->get_int();
  return JVMFlag::SUCCESS;
}

JVMFlag::Error JVMFlag::intAtPut(JVMFlag* flag, int* value, JVMFlag::Flags origin) {
  const char* name;
  if (flag == NULL) return JVMFlag::INVALID_FLAG;
  if (!flag->is_int()) return JVMFlag::WRONG_FORMAT;
  name = flag->_name;
  JVMFlag::Error check = apply_constraint_and_check_range_int(name, *value, !JVMFlagConstraintList::validated_after_ergo());
  if (check != JVMFlag::SUCCESS) return check;
  int old_value = flag->get_int();
  trace_flag_changed<EventIntFlagChanged, s4>(name, old_value, *value, origin);
  check = flag->set_int(*value);
  *value = old_value;
  flag->set_origin(origin);
  return check;
}

JVMFlag::Error JVMFlag::intAtPut(const char* name, size_t len, int* value, JVMFlag::Flags origin) {
  JVMFlag* result = JVMFlag::find_flag(name, len);
  return intAtPut(result, value, origin);
}

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

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

Examples 3
Example event data values and properties
name string
HeapDumpGzipLevel
newValue int
1
oldValue int
0
origin FlagValueOrigin
Management
startTime long: millis
1402046663
Example event data values and properties
name string
HeapDumpGzipLevel
newValue int
0
oldValue int
1
origin FlagValueOrigin
Management
startTime long: millis
982266203
Example event data values and properties
name string
HeapDumpGzipLevel
newValue int
1
oldValue int
0
origin FlagValueOrigin
Management
startTime long: millis
1312184730

UnsignedIntFlagChanged

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

  if (!result->is_uint()) return JVMFlag::WRONG_FORMAT;
  *value = result->get_uint();
  return JVMFlag::SUCCESS;
}

JVMFlag::Error JVMFlag::uintAtPut(JVMFlag* flag, uint* value, JVMFlag::Flags origin) {
  const char* name;
  if (flag == NULL) return JVMFlag::INVALID_FLAG;
  if (!flag->is_uint()) return JVMFlag::WRONG_FORMAT;
  name = flag->_name;
  JVMFlag::Error check = apply_constraint_and_check_range_uint(name, *value, !JVMFlagConstraintList::validated_after_ergo());
  if (check != JVMFlag::SUCCESS) return check;
  uint old_value = flag->get_uint();
  trace_flag_changed<EventUnsignedIntFlagChanged, u4>(name, old_value, *value, origin);
  check = flag->set_uint(*value);
  *value = old_value;
  flag->set_origin(origin);
  return check;
}

JVMFlag::Error JVMFlag::uintAtPut(const char* name, size_t len, uint* value, JVMFlag::Flags origin) {
  JVMFlag* result = JVMFlag::find_flag(name, len);
  return uintAtPut(result, value, origin);
}

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

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

Examples 3
Example event data values and properties
name string
FullGCHeapDumpLimit
newValue uint
1
oldValue uint
0
origin FlagValueOrigin
Management
startTime long: millis
1402099641
Example event data values and properties
name string
FullGCHeapDumpLimit
newValue uint
0
oldValue uint
1
origin FlagValueOrigin
Management
startTime long: millis
982288656
Example event data values and properties
name string
FullGCHeapDumpLimit
newValue uint
1
oldValue uint
0
origin FlagValueOrigin
Management
startTime long: millis
1312238230

LongFlagChanged

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

Code Context

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

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

JVMFlag::Error JVMFlag::intxAtPut(JVMFlag* flag, intx* value, JVMFlag::Flags origin) {
  const char* name;
  if (flag == NULL) return JVMFlag::INVALID_FLAG;
  if (!flag->is_intx()) return JVMFlag::WRONG_FORMAT;
  name = flag->_name;
  JVMFlag::Error check = apply_constraint_and_check_range_intx(name, *value, !JVMFlagConstraintList::validated_after_ergo());
  if (check != JVMFlag::SUCCESS) return check;
  intx old_value = flag->get_intx();
  trace_flag_changed<EventLongFlagChanged, intx>(name, old_value, *value, origin);
  check = flag->set_intx(*value);
  *value = old_value;
  flag->set_origin(origin);
  return check;
}

JVMFlag::Error JVMFlag::intxAtPut(const char* name, size_t len, intx* value, JVMFlag::Flags origin) {
  JVMFlag* result = JVMFlag::find_flag(name, len);
  return intxAtPut(result, value, origin);
}

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

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

UnsignedLongFlagChanged

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

JVMFlag::Error JVMFlag::uintxAtPut(JVMFlag* flag, uintx* value, JVMFlag::Flags origin) {
  const char* name;
  if (flag == NULL) return JVMFlag::INVALID_FLAG;
  if (!flag->is_uintx()) return JVMFlag::WRONG_FORMAT;
  name = flag->_name;
  JVMFlag::Error check = apply_constraint_and_check_range_uintx(name, *value, !JVMFlagConstraintList::validated_after_ergo());
  if (check != JVMFlag::SUCCESS) return check;
  uintx old_value = flag->get_uintx();
  trace_flag_changed<EventUnsignedLongFlagChanged, u8>(name, old_value, *value, origin);
  check = flag->set_uintx(*value);
  *value = old_value;
  flag->set_origin(origin);
  return check;
}

JVMFlag::Error JVMFlag::uintxAtPut(const char* name, size_t len, uintx* value, JVMFlag::Flags origin) {
  JVMFlag* result = JVMFlag::find_flag(name, len);
  return uintxAtPut(result, value, origin);
}

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

JVMFlag::Error JVMFlag::uint64_tAtPut(JVMFlag* flag, uint64_t* value, JVMFlag::Flags origin) {
  const char* name;
  if (flag == NULL) return JVMFlag::INVALID_FLAG;
  if (!flag->is_uint64_t()) return JVMFlag::WRONG_FORMAT;
  name = flag->_name;
  JVMFlag::Error check = apply_constraint_and_check_range_uint64_t(name, *value, !JVMFlagConstraintList::validated_after_ergo());
  if (check != JVMFlag::SUCCESS) return check;
  uint64_t old_value = flag->get_uint64_t();
  trace_flag_changed<EventUnsignedLongFlagChanged, u8>(name, old_value, *value, origin);
  check = flag->set_uint64_t(*value);
  *value = old_value;
  flag->set_origin(origin);
  return check;
}

JVMFlag::Error JVMFlag::uint64_tAtPut(const char* name, size_t len, uint64_t* value, JVMFlag::Flags origin) {
  JVMFlag* result = JVMFlag::find_flag(name, len);
  return uint64_tAtPut(result, value, origin);
}

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

JVMFlag::Error JVMFlag::size_tAtPut(JVMFlag* flag, size_t* value, JVMFlag::Flags origin) {
  const char* name;
  if (flag == NULL) return JVMFlag::INVALID_FLAG;
  if (!flag->is_size_t()) return JVMFlag::WRONG_FORMAT;
  name = flag->_name;
  JVMFlag::Error check = apply_constraint_and_check_range_size_t(name, *value, !JVMFlagConstraintList::validated_after_ergo());
  if (check != JVMFlag::SUCCESS) return check;
  size_t old_value = flag->get_size_t();
  trace_flag_changed<EventUnsignedLongFlagChanged, u8>(name, old_value, *value, origin);
  check = flag->set_size_t(*value);
  *value = old_value;
  flag->set_origin(origin);
  return check;
}

JVMFlag::Error JVMFlag::size_tAtPut(const char* name, size_t len, size_t* value, JVMFlag::Flags origin) {
  JVMFlag* result = JVMFlag::find_flag(name, len);
  return size_tAtPut(result, value, origin);
}

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

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

Examples 3
Example event data values and properties
name string
MaxHeapFreeRatio
newValue ulong
70
oldValue ulong
75
origin FlagValueOrigin
Management
startTime long: millis
1401847272
Example event data values and properties
name string
SoftMaxHeapSize
newValue ulong
1863319552
oldValue ulong
4192206848
origin FlagValueOrigin
Management
startTime long: millis
982329037
Example event data values and properties
name string
MinHeapFreeRatio
newValue ulong
40
oldValue ulong
45
origin FlagValueOrigin
Management
startTime long: millis
1311926947

DoubleFlagChanged

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

JVMFlag::Error JVMFlag::doubleAtPut(JVMFlag* flag, double* value, JVMFlag::Flags origin) {
  const char* name;
  if (flag == NULL) return JVMFlag::INVALID_FLAG;
  if (!flag->is_double()) return JVMFlag::WRONG_FORMAT;
  name = flag->_name;
  JVMFlag::Error check = apply_constraint_and_check_range_double(name, *value, !JVMFlagConstraintList::validated_after_ergo());
  if (check != JVMFlag::SUCCESS) return check;
  double old_value = flag->get_double();
  trace_flag_changed<EventDoubleFlagChanged, double>(name, old_value, *value, origin);
  check = flag->set_double(*value);
  *value = old_value;
  flag->set_origin(origin);
  return check;
}

JVMFlag::Error JVMFlag::doubleAtPut(const char* name, size_t len, double* value, JVMFlag::Flags origin) {
  JVMFlag* result = JVMFlag::find_flag(name, len);
  return doubleAtPut(result, value, origin);
}

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

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

Examples 3
Example event data values and properties
name string
G1PeriodicGCSystemLoadThreshold
newValue double
0.5
oldValue double
0.0
origin FlagValueOrigin
Management
startTime long: millis
1401967225
Example event data values and properties
name string
G1PeriodicGCSystemLoadThreshold
newValue double
0.0
oldValue double
0.5
origin FlagValueOrigin
Management
startTime long: millis
982236578
Example event data values and properties
name string
G1PeriodicGCSystemLoadThreshold
newValue double
0.0
oldValue double
0.5
origin FlagValueOrigin
Management
startTime long: millis
1312156697

BooleanFlagChanged

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

  if (!result->is_bool()) return JVMFlag::WRONG_FORMAT;
  *value = result->get_bool();
  return JVMFlag::SUCCESS;
}

JVMFlag::Error JVMFlag::boolAtPut(JVMFlag* flag, bool* value, JVMFlag::Flags origin) {
  const char* name;
  if (flag == NULL) return JVMFlag::INVALID_FLAG;
  if (!flag->is_bool()) return JVMFlag::WRONG_FORMAT;
  name = flag->_name;
  JVMFlag::Error check = apply_constraint_and_check_range_bool(name, *value, !JVMFlagConstraintList::validated_after_ergo());
  if (check != JVMFlag::SUCCESS) return check;
  bool old_value = flag->get_bool();
  trace_flag_changed<EventBooleanFlagChanged, bool>(name, old_value, *value, origin);
  check = flag->set_bool(*value);
  *value = old_value;
  flag->set_origin(origin);
  return check;
}

JVMFlag::Error JVMFlag::boolAtPut(const char* name, size_t len, bool* value, JVMFlag::Flags origin) {
  JVMFlag* result = JVMFlag::find_flag(name, len);
  return boolAtPut(result, value, origin);
}

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

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

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

StringFlagChanged

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

JVMFlag::Error JVMFlag::ccstrAt(const char* name, size_t len, ccstr* value, bool allow_locked, bool return_flag) {
  JVMFlag* result = JVMFlag::find_flag(name, len, allow_locked, return_flag);
  if (result == NULL) return JVMFlag::INVALID_FLAG;
  if (!result->is_ccstr()) return JVMFlag::WRONG_FORMAT;
  *value = result->get_ccstr();
  return JVMFlag::SUCCESS;
}

JVMFlag::Error JVMFlag::ccstrAtPut(const char* name, size_t len, ccstr* value, JVMFlag::Flags origin) {
  JVMFlag* result = JVMFlag::find_flag(name, len);
  if (result == NULL) return JVMFlag::INVALID_FLAG;
  if (!result->is_ccstr()) return JVMFlag::WRONG_FORMAT;
  ccstr old_value = result->get_ccstr();
  trace_flag_changed<EventStringFlagChanged, const char*>(name, old_value, *value, origin);
  char* new_value = NULL;
  if (*value != NULL) {
    new_value = os::strdup_check_oom(*value);
  }
  JVMFlag::Error check = result->set_ccstr(new_value);
  if (result->is_default() && old_value != NULL) {
    // Prior value is NOT heap allocated, but was a literal constant.
    old_value = os::strdup_check_oom(old_value);
  }
  *value = old_value;
  result->set_origin(origin);
  return check;
}

JVMFlag::Error JVMFlagEx::ccstrAtPut(JVMFlagsEnum flag, ccstr value, JVMFlag::Flags origin) {
  JVMFlag* faddr = address_of_flag(flag);
  guarantee(faddr != NULL && faddr->is_ccstr(), "wrong flag type");
  ccstr old_value = faddr->get_ccstr();
  trace_flag_changed<EventStringFlagChanged, const char*>(faddr->_name, old_value, value, origin);
  char* new_value = os::strdup_check_oom(value);
  JVMFlag::Error check = faddr->set_ccstr(new_value);
  if (!faddr->is_default() && old_value != NULL) {
    // Prior value is heap allocated so free it.
    FREE_C_HEAP_ARRAY(char, old_value);
  }
  faddr->set_origin(origin);
  return check;
}

extern "C" {

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

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

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

IntFlag

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

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_native

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

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

Examples 3
Example event data values and properties
name string
ShenandoahCardStatsLogInterval
origin FlagValueOrigin
Default
startTime long: millis
364959265
value int
50
Example event data values and properties
name string
MaxJavaStackTraceDepth
origin FlagValueOrigin
Default
startTime long: millis
454993837499
value int
1024
Example event data values and properties
name string
JavaPriority7_To_OSPriority
origin FlagValueOrigin
Default
startTime long: millis
449445153999
value int
-1

UnsignedIntFlag

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

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_native

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

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

Examples 3
Example event data values and properties
name string
MaxTenuringThreshold
origin FlagValueOrigin
Default
startTime long: millis
364991155
value uint
15
Example event data values and properties
name string
AdaptiveSizeThroughPutPolicy
origin FlagValueOrigin
Default
startTime long: millis
447754326410
value uint
0
Example event data values and properties
name string
GCTimeLimit
origin FlagValueOrigin
Default
startTime long: millis
453049989308
value uint
98

LongFlag

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

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_native

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

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

Examples 3
Example event data values and properties
name string
Tier3DelayOn
origin FlagValueOrigin
Default
startTime long: millis
365023235
value long
5
Example event data values and properties
name string
Tier3InvokeNotifyFreqLog
origin FlagValueOrigin
Default
startTime long: millis
453050006520
value long
10
Example event data values and properties
name string
OptoNodeListSize
origin FlagValueOrigin
Default
startTime long: millis
447754332389
value long
4

UnsignedLongFlag

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

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_native

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

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

Examples 3
Example event data values and properties
name string
MaxVirtMemFraction
origin FlagValueOrigin
Default
startTime long: millis
453050031928
value ulong
2
Example event data values and properties
name string
NUMASpaceResizeRate
origin FlagValueOrigin
Default
startTime long: millis
365046739
value ulong
1073741824
Example event data values and properties
name string
MallocTraceRainyDayFund
origin FlagValueOrigin
Default
startTime long: millis
447754352659
value ulong
1048576

DoubleFlag

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

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_native

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

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

Examples 3
Example event data values and properties
name string
MaxRAMPercentage
origin FlagValueOrigin
Default
startTime long: millis
459805951281
value double
25.0
Example event data values and properties
name string
ZCollectionIntervalMajor
origin FlagValueOrigin
Default
startTime long: millis
454119685141
value double
-1.0
Example event data values and properties
name string
SelfDestructTimer
origin FlagValueOrigin
Default
startTime long: millis
23251912462
value double
0.0

BooleanFlag

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

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_native

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

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

Examples 3
Example event data values and properties
name string
EliminateBlocks
origin FlagValueOrigin
Default
startTime long: millis
453050063767
value boolean
true
Example event data values and properties
name string
StressLinearScan
origin FlagValueOrigin
Default
startTime long: millis
365068500
value boolean
false
Example event data values and properties
name string
DisplayVMOutputToStdout
origin FlagValueOrigin
Default
startTime long: millis
447754415504
value boolean
false

StringFlag

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

Category: Java Virtual Machine / Flag

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

Missing in: graalvm_linux_native

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

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

Examples 3
Example event data values and properties
name string
AOTMode
origin FlagValueOrigin
Default
startTime long: millis
447754449585
value string
null
Example event data values and properties
name string
PrintIdealGraphFile
origin FlagValueOrigin
Default
startTime long: millis
454993979856
value string
null
Example event data values and properties
name string
MallocLimit
origin FlagValueOrigin
Default
startTime long: millis
365144382
value string
null

JVM: GC: Collector

GarbageCollection

default profiling startTime duration 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Collector

Garbage collection performed by the JVM

Code Context

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

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

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

typedef uintptr_t TraceAddress;

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

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

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

Examples 3
Example event data values and properties
cause GCCause
G1 Humongous Allocation
gcId uint
1162
longestPause Tickspan
109274022
name GCName
G1Old
startTime long: millis
479822801969
sumOfPauses Tickspan
109274022
Example event data values and properties
cause GCCause
System.gc()
gcId uint
374
longestPause Tickspan
382046310
name GCName
ParallelOld
startTime long: millis
492366463917
sumOfPauses Tickspan
382046310
Example event data values and properties
cause GCCause
System.gc()
gcId uint
91
longestPause Tickspan
18131890
name GCName
G1Full
startTime long: millis
2192946267
sumOfPauses Tickspan
18131890

ParallelOldGarbageCollection

default profiling startTime duration 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Collector

Appearing in: linux_ParallelGC

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

Extra information specific to Parallel Old Garbage Collections

Code Context

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

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

    e.set_smallChunksTotalSize(summary.small_chunks_size_in_bytes());

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

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

    e.commit();
  }
}

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

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

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

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

Examples 2
Example event data values and properties
densePrefix ulong: address
30172250112
gcId uint
367
startTime long: millis
481401386106
Example event data values and properties
densePrefix ulong: address
30173822976
gcId uint
59
startTime long: millis
1781630209

YoungGarbageCollection

default profiling startTime duration 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Collector

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

Extra information specific to Young Garbage Collections

Code Context

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
gcId uint
1164
startTime long: millis
480903210866
tenuringThreshold uint
15
Example event data values and properties
gcId uint
359
startTime long: millis
475922080802
tenuringThreshold uint
1
Example event data values and properties
gcId uint
21
startTime long: millis
1262351619
tenuringThreshold uint
15

OldGarbageCollection

default profiling startTime duration 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Collector

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

Extra information specific to Old Garbage Collections

Code Context

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
gcId uint
66
startTime long: millis
1933917383
Example event data values and properties
gcId uint
1188
startTime long: millis
510409120603
Example event data values and properties
gcId uint
358
startTime long: millis
475284085446

G1GarbageCollection

default profiling startTime duration 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Collector

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Extra information specific to G1 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:

                                                  double predicted_allocation_rate,
                                                  double predicted_marking_length,
                                                  bool prediction_active) {
  send_adaptive_ihop_statistics(threshold,
                                internal_target_occupancy,
                                additional_buffer_size,
                                current_occupancy,
                                predicted_allocation_rate,
                                predicted_marking_length,
                                prediction_active);
}

void G1NewTracer::send_g1_young_gc_event() {
  EventG1GarbageCollection e(UNTIMED);
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_type(_g1_young_gc_info.type());
    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
default true 0 ms
profiling true 0 ms

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

Examples 3
Example event data values and properties
gcId uint
1257
startTime long: millis
498485743160
type G1YCType
Concurrent Start
Example event data values and properties
gcId uint
1155
startTime long: millis
477753846911
type G1YCType
Concurrent Start
Example event data values and properties
gcId uint
113
startTime long: millis
2448157856
type G1YCType
Normal

JVM: GC: Configuration

GCConfiguration

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

Category: Java Virtual Machine / GC / Configuration

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

Missing in: graalvm_linux_native

The configuration of the garbage collector

Code Context

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
concurrentGCThreads uint
1
gcTimeRatio uint
12
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
G1Old
parallelGCThreads uint
4
pauseTarget long: millis
-9223372036854775808
startTime long: millis
489354002365
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
494787681678
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
15520480215
usesDynamicGCThreads boolean
true
youngCollector GCName
G1New

GCSurvivorConfiguration

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

Category: Java Virtual Machine / GC / Configuration

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

Missing in: graalvm_linux_native

The configuration of the survivors of garbage collection

Code Context

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

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

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

TRACE_REQUEST_FUNC(GCSurvivorConfiguration) {
  GCSurvivorConfiguration conf;
  EventGCSurvivorConfiguration event;
  event.set_maxTenuringThreshold(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
default true beginChunk
profiling true beginChunk

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

Examples 3
Example event data values and properties
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
453271938030
Example event data values and properties
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
447960957276
Example event data values and properties
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
8048575517

GCTLABConfiguration

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

Category: Java Virtual Machine / GC / Configuration

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

Missing in: graalvm_linux_native

The configuration of the Thread Local Allocation Buffers (TLABs)

Code Context

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

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

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

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

Examples 3
Example event data values and properties
minTLABSize ulong: bytes
2048
startTime long: millis
447960958298
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
Example event data values and properties
minTLABSize ulong: bytes
2048
startTime long: millis
15645412440
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
Example event data values and properties
minTLABSize ulong: bytes
2048
startTime long: millis
497004696513
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true

GCHeapConfiguration

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

Category: Java Virtual Machine / GC / Configuration

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

Missing in: graalvm_linux_native

The configuration of the garbage collected heap

Code Context

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

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

  event.commit();
}

TRACE_REQUEST_FUNC(GCSurvivorConfiguration) {
  GCSurvivorConfiguration conf;
  EventGCSurvivorConfiguration event;
  event.set_maxTenuringThreshold(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
default true beginChunk
profiling true beginChunk

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

Examples 3
Example event data values and properties
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
262144000
maxSize ulong: bytes
4192206848
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
460013997897
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
455797549797
usesCompressedOops boolean
true
Example event data values and properties
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
262144000
maxSize ulong: bytes
4192206848
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
23271499268
usesCompressedOops boolean
true

YoungGenerationConfiguration

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

Category: Java Virtual Machine / GC / Configuration

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

Missing in: graalvm_linux_native

The configuration of the young generation of the garbage collected heap

Code Context

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

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

  event.set_minSize(conf.min_size());
  event.set_maxSize(conf.max_size());
  event.set_initialSize(conf.initial_size());
  event.set_usesCompressedOops(conf.uses_compressed_oops());
  event.set_compressedOopsMode(conf.narrow_oop_mode());
  event.set_objectAlignment(conf.object_alignment_in_bytes());
  event.set_heapAddressBits(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
default true beginChunk
profiling true beginChunk

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

Examples 3
Example event data values and properties
maxSize ulong: bytes
2514485248
minSize ulong: bytes
1363144
newRatio uint
2
startTime long: millis
497004698567
Example event data values and properties
maxSize ulong: bytes
1396703232
minSize ulong: bytes
85983232
newRatio uint
2
startTime long: millis
471028231691
Example event data values and properties
maxSize ulong: bytes
2514485248
minSize ulong: bytes
1363144
newRatio uint
2
startTime long: millis
375565483

JVM: GC: Detailed

G1MMU

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Code Context

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

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
gcId uint
70
gcTime long: millis
7
pauseTarget long: millis
200
startTime long: millis
1995454247
timeSlice long: millis
201
Example event data values and properties
gcId uint
1140
gcTime long: millis
7
pauseTarget long: millis
200
startTime long: millis
473413406090
timeSlice long: millis
201
Example event data values and properties
gcId uint
1199
gcTime long: millis
5
pauseTarget long: millis
200
startTime long: millis
483794355061
timeSlice long: millis
201

EvacuationInformation

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Code Context

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

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

void G1NewTracer::send_g1_young_gc_event() {
  EventG1GarbageCollection e(UNTIMED);
  if (e.should_commit()) {
    e.set_gcId(GCId::current());
    e.set_type(_g1_young_gc_info.type());
    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_copied());
    e.set_bytesCopied(info->bytes_copied());
    e.set_regionsFreed(info->regions_freed());
    e.commit();

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

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

Examples 3
Example event data values and properties
allocationRegions uint
3
allocationRegionsUsedAfter ulong: bytes
4235424
allocationRegionsUsedBefore ulong: bytes
69904
bytesCopied ulong: bytes
4165520
cSetRegions uint
4
cSetUsedAfter ulong: bytes
0
cSetUsedBefore ulong: bytes
7978112
gcId uint
117
regionsFreed uint
4
startTime long: millis
2498525652
Example event data values and properties
allocationRegions uint
2
allocationRegionsUsedAfter ulong: bytes
1571144
allocationRegionsUsedBefore ulong: bytes
0
bytesCopied ulong: bytes
1571144
cSetRegions uint
134
cSetUsedAfter ulong: bytes
0
cSetUsedBefore ulong: bytes
277841640
gcId uint
1140
regionsFreed uint
134
startTime long: millis
473413456945
Example event data values and properties
allocationRegions uint
1
allocationRegionsUsedAfter ulong: bytes
168096
allocationRegionsUsedBefore ulong: bytes
0
bytesCopied ulong: bytes
168096
cSetRegions uint
9
cSetUsedAfter ulong: bytes
0
cSetUsedBefore ulong: bytes
16865304
gcId uint
1196
regionsFreed uint
9
startTime long: millis
483560762645

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
default false
profiling false

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

Examples 3
Example event data values and properties
count long
4263
gcId uint
3
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
8
name string
java/util/concurrent/ConcurrentHashMap$Node
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent
startTime long: millis
580280055
totalSize ulong: bytes
102312
Example event data values and properties
count long
7247
gcId uint
1067
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[J
package Package
null
startTime long: millis
453199618606
totalSize ulong: bytes
1230368
Example event data values and properties
count long
54104
gcId uint
341
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
8
name string
java/util/LinkedHashMap$Entry
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util
startTime long: millis
450754001835
totalSize ulong: bytes
1731328

G1EvacuationYoungStatistics

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Memory related evacuation statistics during GC for the young generation

Code Context

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
startTime long: millis
490937234821
statistics G1EvacuationStatistics
allocated ulong: bytes
93576
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1231
regionEndWaste ulong: bytes
0
regionsRefilled uint: bytes
1
undoWaste ulong: bytes
0
used ulong: bytes
12992
wasted ulong: bytes
0
Example event data values and properties
startTime long: millis
473411292046
statistics G1EvacuationStatistics
allocated ulong: bytes
319424
directAllocated ulong: bytes
1090312
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1140
regionEndWaste ulong: bytes
0
regionsRefilled uint: bytes
1
undoWaste ulong: bytes
0
used ulong: bytes
304656
wasted ulong: bytes
3104
Example event data values and properties
startTime long: millis
1495957903
statistics G1EvacuationStatistics
allocated ulong: bytes
2097152
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
27
regionEndWaste ulong: bytes
0
regionsRefilled uint: bytes
1
undoWaste ulong: bytes
0
used ulong: bytes
2043680
wasted ulong: bytes
53472

G1EvacuationOldStatistics

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Memory related evacuation statistics during GC for the old generation

Code Context

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

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
startTime long: millis
2549542751
statistics G1EvacuationStatistics
allocated ulong: bytes
0
directAllocated ulong: bytes
12336
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
121
regionEndWaste ulong: bytes
0
regionsRefilled uint: bytes
1
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0
Example event data values and properties
startTime long: millis
484654618127
statistics G1EvacuationStatistics
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1171
regionEndWaste ulong: bytes
0
regionsRefilled uint: bytes
1
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0
Example event data values and properties
startTime long: millis
528078650691
statistics G1EvacuationStatistics
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1283
regionEndWaste ulong: bytes
0
regionsRefilled uint: bytes
0
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0

G1BasicIHOP

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Basic statistics related to current IHOP calculation

Code Context

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

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

  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
default true
profiling true

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

Examples 3
Example event data values and properties
currentOccupancy ulong: bytes
14040960
gcId uint
17
lastMarkingDuration long: millis
50
recentAllocationRate double: bytes-per-second
0.0
recentMutatorAllocationSize ulong: bytes
0
recentMutatorDuration long: millis
51
startTime long: millis
980856397
targetOccupancy ulong: bytes
178257920
threshold ulong: bytes
80216064
thresholdPercentage float: percentage
0.45
Example event data values and properties
currentOccupancy ulong: bytes
272549632
gcId uint
1196
lastMarkingDuration long: millis
1290
recentAllocationRate double: bytes-per-second
0.0
recentMutatorAllocationSize ulong: bytes
0
recentMutatorDuration long: millis
123
startTime long: millis
483560726918
targetOccupancy ulong: bytes
2231369728
threshold ulong: bytes
46266468
thresholdPercentage float: percentage
0.02073456
Example event data values and properties
currentOccupancy ulong: bytes
458003600
gcId uint
1104
lastMarkingDuration long: millis
1109
recentAllocationRate double: bytes-per-second
2.958066287106632E8
recentMutatorAllocationSize ulong: bytes
205520896
recentMutatorDuration long: millis
694
startTime long: millis
463183510127
targetOccupancy ulong: bytes
861929472
threshold ulong: bytes
208549810
thresholdPercentage float: percentage
0.24195693

G1AdaptiveIHOP

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Statistics related to current adaptive IHOP calculation

Code Context

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

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

    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
default true
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
threshold ulong: bytes Threshold Current IHOP Threshold
thresholdPercentage float: percentage Threshold Current IHOP threshold in percent of the internal target occupancy
ihopTargetOccupancy ulong: bytes IHOP Target Occupancy Internal target old generation occupancy to reach at the start of mixed GC
currentOccupancy ulong: bytes Current Occupancy Current old generation occupancy
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 initial mark 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
6291456
currentOccupancy ulong: bytes
18503264
gcId uint
140
ihopTargetOccupancy ulong: bytes
27892121
predictedAllocationRate double: bytes-per-second
8.482496313772826E8
predictedMarkingDuration long: millis
100
predictionActive boolean
false
startTime long: millis
2818529009
threshold ulong: bytes
13212057
thresholdPercentage float: percentage
0.4736842
Example event data values and properties
additionalBufferSize ulong: bytes
515899392
currentOccupancy ulong: bytes
254410128
gcId uint
1102
ihopTargetOccupancy ulong: bytes
816840704
predictedAllocationRate double: bytes-per-second
1.434936509750703E8
predictedMarkingDuration long: millis
1565
predictionActive boolean
true
startTime long: millis
462385665592
threshold ulong: bytes
76288525
thresholdPercentage float: percentage
0.093394615
Example event data values and properties
additionalBufferSize ulong: bytes
1335885824
currentOccupancy ulong: bytes
272586784
gcId uint
1181
ihopTargetOccupancy ulong: bytes
2117808947
predictedAllocationRate double: bytes-per-second
4.132570245680424E8
predictedMarkingDuration long: millis
2036
predictionActive boolean
true
startTime long: millis
479548703618
threshold ulong: bytes
0
thresholdPercentage float: percentage
0.0

PromoteObjectInNewPLAB

profiling startTime eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC

Missing in: graalvm_linux_native, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Object survived scavenge and was copied to a new Promotion Local Allocation Buffer (PLAB). Supported GCs are Parallel 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
default false
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier Identifier signifying GC during which the object was promoted
objectClass Class Object Class Class of promoted object
objectSize ulong: bytes Object Size Size of promoted object
tenuringAge uint Object Tenuring Age Tenuring age of a surviving object before being copied. The tenuring age of an object is a value between 0-15 and is incremented each 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
1070
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
13504
startTime long: millis
454094112010
tenured boolean
false
tenuringAge uint
0
Example event data values and properties
gcId uint
352
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
org/apache/spark/ui/scope/RDDOperationNode
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/ui/scope
objectSize ulong: bytes
32
plabSize ulong: bytes
32760
startTime long: millis
465224491657
tenured boolean
false
tenuringAge uint
0
Example event data values and properties
gcId uint
5
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
objectSize ulong: bytes
24
plabSize ulong: bytes
63672
startTime long: millis
575064816
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
default false
profiling true

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier Identifier signifying GC during which the object was promoted
objectClass Class Object Class Class of promoted object
objectSize ulong: bytes Object Size Size of promoted object
tenuringAge uint Object Tenuring Age Tenuring age of a surviving object before being copied. The tenuring age of an object is a value between 0-15 and is incremented each 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
1071
objectClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1041
name string
[Lorg/apache/spark/mllib/linalg/Vector;
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/linalg
objectSize ulong: bytes
7216
startTime long: millis
454587117284
tenured boolean
true
tenuringAge uint
0
Example event data values and properties
gcId uint
352
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
objectSize ulong: bytes
23616
startTime long: millis
465224318316
tenured boolean
false
tenuringAge uint
0
Example event data values and properties
gcId uint
1
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
objectSize ulong: bytes
4112
startTime long: millis
564215417
tenured boolean
false
tenuringAge uint
0

PromotionFailed

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Promotion of an object failed

Code Context

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

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

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

// Common to CMS and G1
void OldGCTracer::send_concurrent_mode_failure_event() {
  EventConcurrentModeFailure e;

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

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

EvacuationFailed

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Evacuation of an object failed

Code Context

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

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

    e.set_cSetRegions(info->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_copied());
    e.set_bytesCopied(info->bytes_copied());
    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());
    evac_failed.set_smallestSize(ef_info.smallest_size());
    evac_failed.set_totalSize(ef_info.total_size());
    // Add to the event
    e.set_gcId(GCId::current());
    e.set_evacuationFailed(evac_failed);
    e.commit();

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

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

ConcurrentModeFailure

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Concurrent Mode failed

Code Context

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
gcId uint
761
startTime long: millis
10512260824
Example event data values and properties
gcId uint
1125
startTime long: millis
468957467511
Example event data values and properties
gcId uint
1277
startTime long: millis
518095347708

AllocationRequiringGC

startTime eventThread stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

Code Context

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
gcId uint
6
size ulong: bytes
4112
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
24
lineNumber int
494
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
allocateAndGC
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
611174609
Example event data values and properties
gcId uint
1105
size ulong: bytes
56
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
8
lineNumber int
2695
method Method
descriptor string
(I[Lorg/apache/xbean/asm9/Label;)Lorg/apache/xbean/asm9/Label;
hidden boolean
false
modifiers int
4
name string
readLabel
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/xbean/asm9/ClassReader
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/xbean/asm9
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
463575186407
Example event data values and properties
gcId uint
362
size ulong: bytes
16
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
12
lineNumber int
500
method Method
descriptor string
(Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
false
modifiers int
8
name string
allocateInstance
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/invoke/DirectMethodHandle
package Package
exported boolean
true
module Module
classLoader ClassLoader
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
type FrameType
Inlined
…
truncated boolean
true
startTime long: millis
477022943997

TenuringDistribution

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Detailed

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_ShenandoahGC, linux_ZGC

Code Context

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

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

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

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

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

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

Examples 3
Example event data values and properties
age uint
13
gcId uint
1071
size ulong: bytes
0
startTime long: millis
454592203524
Example event data values and properties
age uint
6
gcId uint
7
size ulong: bytes
0
startTime long: millis
624773492
Example event data values and properties
age uint
8
gcId uint
1363
size ulong: bytes
0
startTime long: millis
557690111670

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
default false
profiling false

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

Examples 3
Example event data values and properties
from G1HeapRegionType
Free
index uint
366
start ulong: address
30932992000
startTime long: millis
475615721012
to G1HeapRegionType
Eden
used ulong: bytes
0
Example event data values and properties
from G1HeapRegionType
Free
index uint
118
start ulong: address
30414995456
startTime long: millis
453405618156
to G1HeapRegionType
Continues Humongous
used ulong: bytes
0
Example event data values and properties
from G1HeapRegionType
Old
index uint
3
start ulong: address
30173822976
startTime long: millis
374667272
to G1HeapRegionType
Free
used ulong: bytes
623864

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
default false everyChunk
profiling false everyChunk

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

Examples 3
Example event data values and properties
count long
57543
gcId uint
1067
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
453199618606
totalSize ulong: bytes
1381032
Example event data values and properties
count long
4900
gcId uint
24
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
1436575917
totalSize ulong: bytes
117600
Example event data values and properties
count long
5487
gcId uint
340
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[C
package Package
null
startTime long: millis
449585050457
totalSize ulong: bytes
6058680

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
default false everyChunk
profiling false everyChunk

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

Examples 3
Example event data values and properties
index uint
29
start ulong: address
30226251776
startTime long: millis
476970586988
type G1HeapRegionType
Old
used ulong: bytes
2097112
Example event data values and properties
index uint
9
start ulong: address
30186405888
startTime long: millis
7877466268
type G1HeapRegionType
Free
used ulong: bytes
0
Example event data values and properties
index uint
281
start ulong: address
30756831232
startTime long: millis
453269698117
type G1HeapRegionType
Free
used ulong: bytes
0

ZPageAllocation

experimental default profiling 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

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/zTracer.cpp:

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

void ZTracer::send_page_alloc(size_t size, size_t used, size_t free, size_t cache, bool nonblocking, bool noreserve) {
  NoSafepointVerifier nsv(true, !SafepointSynchronize::is_at_safepoint());

  EventZPageAllocation e;
  if (e.should_commit()) {
    e.set_pageSize(size);
    e.set_usedAfter(used);
    e.set_freeAfter(free);
    e.set_inCacheAfter(cache);
    e.set_nonBlocking(nonblocking);
    e.set_noReserve(noreserve);
    e.commit();
  }
}

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

Event fields with their types and descriptions
Field Type Description
pageSize ulong: bytes 11 until JDK 15 Page Size
usedAfter ulong: bytes 11 until JDK 15 Used After
freeAfter ulong: bytes 11 until JDK 15 Free After
inCacheAfter ulong: bytes 11 until JDK 15 In Cache After
nonBlocking boolean Non-blocking
noReserve boolean 11 until JDK 16 No Reserve

Examples 2
Example event data values and properties
nonBlocking boolean
false
startTime long: millis
680535093
Example event data values and properties
nonBlocking boolean
false
startTime long: millis
619392849087

ZThreadPhase

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

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

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

Code Context

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

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

  NoSafepointVerifier nsv(true, !SafepointSynchronize::is_at_safepoint());

  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(true, !SafepointSynchronize::is_at_safepoint());

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

void ZTracer::send_page_alloc(size_t size, size_t used, size_t free, size_t cache, bool nonblocking, bool noreserve) {
  NoSafepointVerifier nsv(true, !SafepointSynchronize::is_at_safepoint());

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

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

Examples 2
Example event data values and properties
gcId uint
257
name string
Concurrent Mark Roots
startTime long: millis
621311965252
Example event data values and properties
gcId uint
2
name string
Concurrent Mark Follow
startTime long: millis
1486631462

ZStatisticsCounter

experimental default profiling 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(uint32_t counter_id, uint64_t increment, uint64_t value) {
  NoSafepointVerifier nsv(true, !SafepointSynchronize::is_at_safepoint());

  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(uint32_t sampler_id, uint64_t value) {
  NoSafepointVerifier nsv(true, !SafepointSynchronize::is_at_safepoint());

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 10 ms
profiling true 10 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
863394221
value ulong
88080384
Example event data values and properties
id ZStatisticsCounterType
Allocation Rate
increment ulong
2097152
startTime long: millis
619402914073
value ulong
60817408

ZStatisticsSampler

experimental default profiling 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(uint32_t sampler_id, uint64_t value) {
  NoSafepointVerifier nsv(true, !SafepointSynchronize::is_at_safepoint());

  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(true, !SafepointSynchronize::is_at_safepoint());

  EventZThreadPhase e(UNTIMED);

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 10 ms
profiling true 10 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
Young Generation (Collect Roots)
startTime long: millis
621311949960
value ulong
43064966
Example event data values and properties
id ZStatisticsSamplerType
Concurrent Roots OopStorageSet
startTime long: millis
957822223
value ulong
1813

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() {
  if (!_heap->is_heap_region_special() && !os::uncommit_memory((char *) _reserved.start(), _reserved.byte_size())) {
    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)region_number());
    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
default false
profiling false

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

Examples 2
Example event data values and properties
from ShenandoahHeapRegionState
Empty Committed
index uint
3527
start ulong: address
33865859072
startTime long: millis
549809616207
to ShenandoahHeapRegionState
Empty Uncommitted
used ulong: bytes
0
Example event data values and properties
from ShenandoahHeapRegionState
Empty Uncommitted
index uint
3707
start ulong: address
34054602752
startTime long: millis
632110863
to ShenandoahHeapRegionState
Regular
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,
                                     false,
                                     true,
                                     new ShenandoahHeapRegionStateConstant());
}
#endif

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

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

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

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

Examples 2
Example event data values and properties
index uint
26
start ulong: address
30194794496
startTime long: millis
388497656
state ShenandoahHeapRegionState
Empty Committed
used ulong: bytes
0
Example event data values and properties
index uint
19
start ulong: address
30187454464
startTime long: millis
551404914377
state ShenandoahHeapRegionState
Humongous Continuation
used ulong: bytes
1048576

JVM: GC: Heap

GCHeapSummary

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Heap

Code Context

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

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

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
gcId uint
1093
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
254359000
startTime long: millis
460012861992
when GCWhen
After GC
Example event data values and properties
gcId uint
47
heapSpace VirtualSpace
committedEnd ulong: address
30196891648
committedSize ulong: bytes
29360128
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
heapUsed ulong: bytes
9111192
startTime long: millis
1769622213
when GCWhen
After GC
Example event data values and properties
gcId uint
352
heapSpace VirtualSpace
committedEnd ulong: address
33571209216
committedSize ulong: bytes
3403677696
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
heapUsed ulong: bytes
1425194464
startTime long: millis
465223148298
when GCWhen
Before GC

MetaspaceSummary

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Heap

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

Missing in: graalvm_linux_native

Code Context

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

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

static JfrStructMetaspaceSizes to_struct(const MetaspaceSizes& 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.meta_space()));
    e.set_dataSpace(to_struct(meta_space_summary.data_space()));
    e.set_classSpace(to_struct(meta_space_summary.class_space()));
    e.commit();
  }
}

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

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

Examples 3
Example event data values and properties
classSpace MetaspaceSizes
committed ulong: bytes
179109888
reserved ulong: bytes
1073741824
used ulong: bytes
177469768
dataSpace MetaspaceSizes
committed ulong: bytes
777977856
reserved ulong: bytes
805306368
used ulong: bytes
776114584
gcId uint
348
gcThreshold ulong: bytes
1595146240
metaspace MetaspaceSizes
committed ulong: bytes
957087744
reserved ulong: bytes
1879048192
used ulong: bytes
953584352
startTime long: millis
458019250585
when GCWhen
After GC
Example event data values and properties
classSpace MetaspaceSizes
committed ulong: bytes
179175424
reserved ulong: bytes
1073741824
used ulong: bytes
177476696
dataSpace MetaspaceSizes
committed ulong: bytes
778436608
reserved ulong: bytes
805306368
used ulong: bytes
776588208
gcId uint
1096
gcThreshold ulong: bytes
1595932672
metaspace MetaspaceSizes
committed ulong: bytes
957612032
reserved ulong: bytes
1879048192
used ulong: bytes
954064904
startTime long: millis
461057370907
when GCWhen
Before GC
Example event data values and properties
classSpace MetaspaceSizes
committed ulong: bytes
2949120
reserved ulong: bytes
1073741824
used ulong: bytes
2839560
dataSpace MetaspaceSizes
committed ulong: bytes
11927552
reserved ulong: bytes
67108864
used ulong: bytes
11797400
gcId uint
23
gcThreshold ulong: bytes
24707072
metaspace MetaspaceSizes
committed ulong: bytes
14876672
reserved ulong: bytes
1140850688
used ulong: bytes
14636960
startTime long: millis
1405025210
when GCWhen
Before GC

PSHeapSummary

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Heap

Appearing in: linux_ParallelGC

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

Code Context

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

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

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

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

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

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

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

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

Examples 2
Example event data values and properties
edenSpace ObjectSpace
end ulong: address
33478934528
size ulong: bytes
515899392
start ulong: address
32963035136
used ulong: bytes
27147280
fromSpace ObjectSpace
end ulong: address
33491517440
size ulong: bytes
6291456
start ulong: address
33485225984
used ulong: bytes
0
gcId uint
15
oldObjectSpace ObjectSpace
end ulong: address
30343692288
size ulong: bytes
176160768
start ulong: address
30167531520
used ulong: bytes
6551144
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
1149526087
toSpace ObjectSpace
end ulong: address
33485225984
size ulong: bytes
6291456
start ulong: address
33478934528
used ulong: bytes
0
when GCWhen
Before GC
youngSpace VirtualSpace
committedEnd ulong: address
33491517440
committedSize ulong: bytes
528482304
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
1396703232
start ulong: address
32963035136
Example event data values and properties
edenSpace ObjectSpace
end ulong: address
33885782016
size ulong: bytes
922746880
start ulong: address
32963035136
used ulong: bytes
922746880
fromSpace ObjectSpace
end ulong: address
34070331392
size ulong: bytes
6291456
start ulong: address
34064039936
used ulong: bytes
5062704
gcId uint
362
oldObjectSpace ObjectSpace
end ulong: address
32398901248
size ulong: bytes
2231369728
start ulong: address
30167531520
used ulong: bytes
232519720
oldSpace VirtualSpace
committedEnd ulong: address
32398901248
committedSize ulong: bytes
2231369728
reservedEnd ulong: address
32963035136
reservedSize ulong: bytes
2795503616
start ulong: address
30167531520
startTime long: millis
477023037604
toSpace ObjectSpace
end ulong: address
33999028224
size ulong: bytes
71303168
start ulong: address
33927725056
used ulong: bytes
0
when GCWhen
Before GC
youngSpace VirtualSpace
committedEnd ulong: address
34070331392
committedSize ulong: bytes
1107296256
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
1396703232
start ulong: address
32963035136

G1HeapSummary

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Heap

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

Code Context

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
edenTotalSize ulong: bytes
391482688
edenUsedSize ulong: bytes
0
gcId uint
1211
numberOfRegions uint
439
startTime long: millis
487139934469
survivorUsedSize ulong: bytes
2781888
when GCWhen
After GC
Example event data values and properties
edenTotalSize ulong: bytes
28419888
edenUsedSize ulong: bytes
25165824
gcId uint
9
numberOfRegions uint
32
startTime long: millis
654407850
survivorUsedSize ulong: bytes
3037392
when GCWhen
Before GC
Example event data values and properties
edenTotalSize ulong: bytes
520093696
edenUsedSize ulong: bytes
0
gcId uint
1082
numberOfRegions uint
414
startTime long: millis
456898951526
survivorUsedSize ulong: bytes
0
when GCWhen
After GC

JVM: GC: Metaspace

MetaspaceGCThreshold

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Metaspace

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

Missing in: graalvm_linux_native

Code Context

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

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

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

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

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

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

Examples 3
Example event data values and properties
newValue ulong: bytes
25690112
oldValue ulong: bytes
25362432
startTime long: millis
19732159684
updater GCThresholdUpdater
compute_new_size
Example event data values and properties
newValue ulong: bytes
1594621952
oldValue ulong: bytes
1594163200
startTime long: millis
454878011521
updater GCThresholdUpdater
compute_new_size
Example event data values and properties
newValue ulong: bytes
1603338240
oldValue ulong: bytes
1596915712
startTime long: millis
481703724433
updater GCThresholdUpdater
compute_new_size

MetaspaceAllocationFailure

default profiling startTime stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Metaspace

Code Context

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

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

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

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

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

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

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

Event fields with their types and descriptions
Field Type Description
classLoader ClassLoader Class Loader
unsafeAnonymousClassLoader boolean until JDK 15 Unsafe Anonymous Class Loader
size ulong: bytes Size
metadataType MetadataType Metadata Type
metaspaceObjectType MetaspaceObjectType Metaspace Object Type

MetaspaceOOM

default profiling startTime stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Metaspace

Code Context

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

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

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

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

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

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

Event fields with their types and descriptions
Field Type Description
classLoader ClassLoader Class Loader
unsafeAnonymousClassLoader boolean until JDK 15 Unsafe Anonymous Class Loader
size ulong: bytes Size
metadataType MetadataType Metadata Type
metaspaceObjectType MetaspaceObjectType Metaspace Object Type

MetaspaceChunkFreeListSummary

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Metaspace

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

Missing in: graalvm_linux_native

Code Context

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

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

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

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

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

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

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

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

Examples 3
Example event data values and properties
gcId uint
1072
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
454661991458
when GCWhen
Before 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
466148700267
when GCWhen
After GC
Example event data values and properties
gcId uint
10
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
672680388
when GCWhen
Before GC

JVM: GC: Phases

GCPhasePause

default profiling startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

Code Context

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

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

    e.set_gcThreshold(meta_space_summary.capacity_until_GC());
    e.set_metaspace(to_struct(meta_space_summary.meta_space()));
    e.set_dataSpace(to_struct(meta_space_summary.data_space()));
    e.set_classSpace(to_struct(meta_space_summary.class_space()));
    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() < 1, "There is only one level for ConcurrentPhase");

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

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

Examples 3
Example event data values and properties
gcId uint
369
name string
GC Pause
startTime long: millis
484653508481
Example event data values and properties
gcId uint
1080
name string
GC Pause
startTime long: millis
456523830458
Example event data values and properties
gcId uint
68
name string
GC Pause
startTime long: millis
1963026829

GCPhasePauseLevel1

default profiling startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

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

Missing in: linux_ZGC

Code Context

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

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

    e.set_metaspace(to_struct(meta_space_summary.meta_space()));
    e.set_dataSpace(to_struct(meta_space_summary.data_space()));
    e.set_classSpace(to_struct(meta_space_summary.class_space()));
    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() < 1, "There is only one level for ConcurrentPhase");

    switch (phase->level()) {

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

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

Examples 3
Example event data values and properties
gcId uint
343
name string
Post Compact
startTime long: millis
452877456500
Example event data values and properties
gcId uint
1092
name string
Phase 5: Reset Metadata
startTime long: millis
459219841790
Example event data values and properties
gcId uint
11
name string
Notify PhantomReferences
startTime long: millis
709861129

GCPhasePauseLevel2

default profiling startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

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

Missing in: linux_ShenandoahGC, linux_ZGC

Code Context

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

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

    e.set_dataSpace(to_struct(meta_space_summary.data_space()));
    e.set_classSpace(to_struct(meta_space_summary.class_space()));
    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() < 1, "There is only one level for ConcurrentPhase");

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

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

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

Examples 3
Example event data values and properties
gcId uint
1085
name string
Phase 2: Prepare parallel compaction
startTime long: millis
457298486448
Example event data values and properties
gcId uint
39
name string
Phase 1: Weak Processing
startTime long: millis
1639797030
Example event data values and properties
gcId uint
347
name string
Reference Processing
startTime long: millis
456734581114

GCPhasePauseLevel3

startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: graalvm_linux_native, linux_ShenandoahGC, linux_ZGC

Code Context

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

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

    e.set_classSpace(to_struct(meta_space_summary.class_space()));
    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() < 1, "There is only one level for ConcurrentPhase");

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

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

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

Examples 3
Example event data values and properties
gcId uint
1075
name string
Purge Class Loader Data
startTime long: millis
455092741582
Example event data values and properties
gcId uint
338
name string
Free Code Blobs
startTime long: millis
447850918822
Example event data values and properties
gcId uint
40
name string
Notify and keep alive finalizable
startTime long: millis
1663092893

GCPhasePauseLevel4

startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ParallelGC

Missing in: graalvm_linux_native, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Code Context

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

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

    e.commit();
  }
}

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

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

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 1, "There is only one level for ConcurrentPhase");

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

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

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

Examples 3
Example event data values and properties
gcId uint
1180
name string
Balance queues
startTime long: millis
496843374095
Example event data values and properties
gcId uint
1241
name string
Balance queues
startTime long: millis
494448060242
Example event data values and properties
gcId uint
376
name string
Balance queues
startTime long: millis
494649287286

GCPhaseConcurrent

default profiling startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ShenandoahGC, linux_ZGC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC

Code Context

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

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

  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:

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() < 1, "There is only one level for ConcurrentPhase");

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

 public:
  template<typename T>
  void send_phase(GCPhase* phase) {
    T event(UNTIMED);
    if (event.should_commit()) {
      event.set_gcId(GCId::current());
      event.set_name(phase->name());

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

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

Examples 3
Example event data values and properties
gcId uint
278
name string
Concurrent thread roots
startTime long: millis
550998673198
Example event data values and properties
gcId uint
1131
name string
Concurrent Scan Root Regions
startTime long: millis
469644850938
Example event data values and properties
gcId uint
496
name string
Concurrent Mark From Roots
startTime long: millis
7131714923

GCPhaseParallel

default profiling startTime duration eventThread 12 17 21 25 27 28

Category: Java Virtual Machine / GC / Phases

Appearing in: graalvm_linux_G1GC, linux_G1GC, linux_ShenandoahGC

Missing in: graalvm_linux_native, linux_ParallelGC, linux_SerialGC, linux_ZGC

GC phases for parallel workers

Code Context

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

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

#define SHARE_GC_SHENANDOAH_SHENANDOAHTIMINGTRACKER_HPP

#include "jfr/jfrEvents.hpp"
#include "gc/shenandoah/shenandoahPhaseTimings.hpp"
#include "memory/allocation.hpp"

class ShenandoahWorkerTimingsTracker : public StackObj {
private:
  double _start_time;
  ShenandoahPhaseTimings::GCParPhases _phase;
  ShenandoahWorkerTimings* _worker_times;
  uint _worker_id;

  EventGCPhaseParallel _event;
public:
    ShenandoahWorkerTimingsTracker(ShenandoahWorkerTimings* worker_times, ShenandoahPhaseTimings::GCParPhases phase, uint worker_id);
    ~ShenandoahWorkerTimingsTracker();
};


class ShenandoahTerminationTimingsTracker : public StackObj {
private:
  double _start_time;
  uint   _worker_id;

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

class ShenandoahConcurrentWorkerSession : public ShenandoahWorkerSession {
private:
  EventGCPhaseConcurrent _event;

public:
  ShenandoahConcurrentWorkerSession(uint worker_id) : ShenandoahWorkerSession(worker_id) { }
  ~ShenandoahConcurrentWorkerSession();
};

class ShenandoahParallelWorkerSession : public ShenandoahWorkerSession {
private:
  EventGCPhaseParallel _event;

public:
  ShenandoahParallelWorkerSession(uint worker_id) : ShenandoahWorkerSession(worker_id) { }
  ~ShenandoahParallelWorkerSession();
};

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

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

  phase_times()->record_evac_fail_remove_self_forwards((os::elapsedTime() - remove_self_forwards_start) * 1000.0);
}

void G1CollectedHeap::preserve_mark_during_evac_failure(uint worker_id, oop obj, markOop m) {
  if (!_evacuation_failed) {
    _evacuation_failed = true;
  }

  _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()->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();
  ParallelCleaningTask unlink_task(is_alive, num_workers, class_unloading_occurred, false);
  workers()->run_task(&unlink_task);
}

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

    double young_time = 0.0;
    bool has_young_time = false;
    double non_young_time = 0.0;
    bool has_non_young_time = false;

    while (true) {
      size_t end = Atomic::add(chunk_size(), &_parallel_work_claim);
      size_t cur = end - chunk_size();

      if (cur >= _num_work_items) {
        break;
      }

      EventGCPhaseParallel event;
      double start_time = os::elapsedTime();

      end = MIN2(end, _num_work_items);

      for (; cur < end; cur++) {
        bool is_young = _work_items[cur].is_young;

        do_parallel_work_for_region(_work_items[cur].region_idx, is_young, _work_items[cur].evacuation_failed);

        double end_time = os::elapsedTime();
        double time_taken = end_time - start_time;

src/hotspot/share/gc/g1/g1GCPhaseTimes.hpp:

public:
  G1EvacPhaseWithTrimTimeTracker(G1ParScanThreadState* pss, Tickspan& total_time, Tickspan& trim_time);
  ~G1EvacPhaseWithTrimTimeTracker();

  void stop();
};

class G1GCParPhaseTimesTracker : public CHeapObj<mtGC> {
protected:
  Ticks _start_time;
  G1GCPhaseTimes::GCParPhases _phase;
  G1GCPhaseTimes* _phase_times;
  uint _worker_id;
  EventGCPhaseParallel _event;
public:
  G1GCParPhaseTimesTracker(G1GCPhaseTimes* phase_times, G1GCPhaseTimes::GCParPhases phase, uint worker_id);
  virtual ~G1GCParPhaseTimesTracker();
};

class G1EvacPhaseTimesTracker : public G1GCParPhaseTimesTracker {
  Tickspan _total_time;
  Tickspan _trim_time;

  G1EvacPhaseWithTrimTimeTracker _trim_tracker;
public:

src/hotspot/share/gc/g1/g1RemSet.cpp:

    _ct->set_card_claimed(card_index);
    _scan_state->add_dirty_region(region_idx_for_card);
  }

  void scan_card(MemRegion mr, uint region_idx_for_card) {
    HeapRegion* const card_region = _g1h->region_at(region_idx_for_card);
    assert(!card_region->is_young(), "Should not scan card in young region %u", region_idx_for_card);
    card_region->oops_on_card_seq_iterate_careful<true>(mr, _scan_objs_on_card_cl);
    _scan_objs_on_card_cl->trim_queue_partially();
    _cards_scanned++;
  }

  void scan_opt_rem_set_roots(HeapRegion* r) {
    EventGCPhaseParallel event;

    G1OopStarChunkedList* opt_rem_set_list = _pss->oops_into_optional_region(r);

    G1ScanCardClosure scan_cl(_g1h, _pss);
    G1ScanRSForOptionalClosure cl(_g1h, &scan_cl);
    _opt_refs_scanned += opt_rem_set_list->oops_do(&cl, _pss->closures()->raw_strong_oops());
    _opt_refs_memory_used += opt_rem_set_list->used_memory();

    event.commit(GCId::current(), _worker_i, G1GCPhaseTimes::phase_name(_phase));
  }

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

    if (_scan_state->claim_iter(region_idx)) {
      // If we ever free the collection set concurrently, we should also
      // clear the card table concurrently therefore we won't need to
      // add regions of the collection set to the dirty cards region.
      _scan_state->add_dirty_region(region_idx);
    }

    if (r->rem_set()->cardset_is_empty()) {
      return;

src/hotspot/share/gc/g1/g1RemSet.cpp:

      // random cards into current survivor, and we would then have an incorrectly
      // claimed card in survivor space. Card table clear does not reset the card table
      // of survivor space regions.
      claim_card(card_index, region_idx_for_card);

      MemRegion const mr(card_start, MIN2(card_start + BOTConstants::N_words, top));

      scan_card(mr, region_idx_for_card);
    }
    event.commit(GCId::current(), _worker_i, G1GCPhaseTimes::phase_name(_phase));
  }

  void scan_strong_code_roots(HeapRegion* r) {
    EventGCPhaseParallel event;
    // We pass a weak code blobs closure to the remembered set scanning because we want to avoid
    // treating the nmethods visited to act as roots for concurrent marking.
    // We only want to make sure that the oops in the nmethods are adjusted with regard to the
    // objects copied by the current evacuation.
    r->strong_code_roots_do(_pss->closures()->weak_codeblobs());
    event.commit(GCId::current(), _worker_i, G1GCPhaseTimes::phase_name(G1GCPhaseTimes::CodeRoots));
  }

public:
  G1ScanRSForRegionClosure(G1RemSetScanState* scan_state,
                           G1ScanCardClosure* scan_obj_on_card,

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

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

Examples 3
Example event data values and properties
gcId uint
281
gcWorkerId uint
0
name string
Finish Mark
startTime long: millis
555465673105
Example event data values and properties
gcId uint
1065
gcWorkerId uint
0
name string
UpdateDerivedPointers
startTime long: millis
453046810046
Example event data values and properties
gcId uint
2
gcWorkerId uint
0
name string
RetireTLABsAndFlushLogs
startTime long: millis
566215692

JVM: GC: Reference

GCReferenceStatistics

default profiling startTime 11 17 21 25 27 28

Category: Java Virtual Machine / GC / Reference

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

Missing in: graalvm_linux_native

Total count of processed references during GC

Code Context

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

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

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

void GCTracer::send_metaspace_chunk_free_list_summary(GCWhen::Type when, Metaspace::MetadataType mdtype,
                                                      const MetaspaceChunkFreeListSummary& summary) const {
  EventMetaspaceChunkFreeListSummary e;

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

Event fields with their types and descriptions
Field Type Description
gcId uint GC Identifier
type ReferenceType Type
count ulong Total Count

Examples 3
Example event data values and properties
count ulong
0
gcId uint
23
startTime long: millis
1405522373
type ReferenceType
Final reference
Example event data values and properties
count ulong
54525
gcId uint
357
startTime long: millis
473621529512
type ReferenceType
Weak reference
Example event data values and properties
count ulong
0
gcId uint
1068
startTime long: millis
453278091389
type ReferenceType
Phantom reference

JVM: Profiling

OldObjectSample

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

Category: Java Virtual Machine / Profiling

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

Missing in: linux_ShenandoahGC, linux_ZGC

A potential memory leak

Code Context

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

src/hotspot/share/jfr/leakprofiler/checkpoint/eventEmitter.cpp:

  if (edge == NULL) {
    // In order to dump out a representation of the event
    // even though it was not reachable / too long to reach,
    // we need to register a top level edge for this object.
    edge = edge_store->put(object_addr);
  } else {
    gc_root_id = edge_store->gc_root_id(edge);
  }

  assert(edge != NULL, "invariant");
  const traceid object_id = edge_store->get_id(edge);
  assert(object_id != 0, "invariant");

  EventOldObjectSample e(UNTIMED);
  e.set_starttime(_start_time);
  e.set_endtime(_end_time);
  e.set_allocationTime(sample->allocation_time());
  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
  // of the commit() call). This trick provides a means to override

src/hotspot/share/jfr/leakprofiler/sampling/objectSampler.cpp:

  const JfrThreadLocal* const tl = thread->jfr_thread_local();
  assert(tl != NULL, "invariant");
  if (!tl->has_thread_blob()) {
    JfrCheckpointManager::create_thread_blob(thread);
  }
  assert(tl->has_thread_blob(), "invariant");
  return tl->thread_id();
}

static void record_stacktrace(JavaThread* thread) {
  assert(thread != NULL, "invariant");
  if (JfrEventSetting::has_stacktrace(EventOldObjectSample::eventId)) {
    JfrStackTraceRepository::record_and_cache(thread);
  }
}

void ObjectSampler::sample(HeapWord* obj, size_t allocated, JavaThread* thread) {
  assert(thread != NULL, "invariant");
  assert(is_created(), "invariant");
  const traceid thread_id = get_thread_id(thread);
  if (thread_id == 0) {
    return;
  }

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);

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

Event fields with their types and descriptions
Field Type Description
allocationTime Ticks Allocation Time
lastKnownHeapUsage ulong: bytes Last Known Heap Usage
object OldObject Object
arrayElements int Array Elements If the object is an array, the number of elements, or -1 if it is not an array
root OldObjectGcRoot GC Root

Examples 3
Example event data values and properties
allocationTime Ticks
734761909
arrayElements int
128
lastKnownHeapUsage ulong: bytes
13982744
object OldObject
address ulong: address
30168595528
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[I
package Package
null
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
68
lineNumber int
4612
method Method
descriptor string
(I[BII)[I
hidden boolean
false
modifiers int
10
name string
stripLeadingZeroBytes
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/math/BigInteger
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/math
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
25440741198
Example event data values and properties
allocationTime Ticks
428309336588
arrayElements int
-2147483648
lastKnownHeapUsage ulong: bytes
198350320
object OldObject
address ulong: address
30366496984
description string
Size: 1
referrer Reference
null
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
0
name string
org/apache/hadoop/metrics2/lib/Interns$CacheWith2Keys$2
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/hadoop/metrics2/lib
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
18
lineNumber int
64
method Method
descriptor string
(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
false
modifiers int
32
name string
add
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1034
name string
org/apache/hadoop/metrics2/lib/Interns$CacheWith2Keys
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/hadoop/metrics2/lib
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
500177878655
Example event data values and properties
allocationTime Ticks
244554643603
arrayElements int
524288
lastKnownHeapUsage ulong: bytes
1514564880
object OldObject
address ulong: address
31562137600
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1040
name string
[Ljava/util/concurrent/ConcurrentHashMap$Node;
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
40
lineNumber int
2447
method Method
descriptor string
([Ljava/util/concurrent/ConcurrentHashMap$Node;[Ljava/util/concurrent/ConcurrentHashMap$Node;)V
hidden boolean
false
modifiers int
18
name string
transfer
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/ConcurrentHashMap
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
510391470765

ExecutionSample

default profiling startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Profiling

Snapshot of a threads state

Code Context

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

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

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

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

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

class OSThreadSampler : public 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(java_lang_Thread::get_thread_status(jth->threadObj()));
    }
  }
}

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:

    assert(_added_java > 0 && _added_java <= MAX_NR_OF_JAVA_SAMPLES, "invariant");
    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");
    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();
    {

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_interval(JNIEnv* env, jobject jvm, jlong type, jlong intervalMillis))
  if (intervalMillis < 0) {
    intervalMillis = 0;
  }
  JfrEventId typed_event_id = (JfrEventId)type;
  assert(EventExecutionSample::eventId == typed_event_id || EventNativeMethodSample::eventId == typed_event_id, "invariant");
  if (intervalMillis > 0) {
    JfrEventSetting::set_enabled(typed_event_id, true); // ensure sampling event is enabled
  }
  if (EventExecutionSample::eventId == type) {
    JfrThreadSampling::set_java_sample_interval(intervalMillis);
  } else {
    JfrThreadSampling::set_native_sample_interval(intervalMillis);
  }
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

Event configuration settings across JFR profiles
Configuration enabled period
default true 20 ms
profiling true 10 ms

Event fields with their types and descriptions
Field Type Description
sampledThread Thread Thread
stackTrace StackTrace Stack Trace
state ThreadState Thread State

Examples 3
Example event data values and properties
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
pool-1-thread-1
javaThreadId long
34
osName string
pool-1-thread-1
osThreadId long
5044
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
245
method Method
descriptor string
()[Ljava/lang/Object;
hidden boolean
false
modifiers int
2
name string
grow
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
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
764718164
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 47.0 (TID 185)
javaThreadId long
1729
osName string
Executor task launch worker for task 3.0 in stage 47.0 (TID 185)
osThreadId long
4645
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
26
lineNumber int
71
method Method
descriptor string
(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
false
modifiers int
1
name string
apply
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1537
name string
breeze/linalg/operators/BinaryRegistry
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg/operators
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
453361552737
state ThreadState
STATE_RUNNABLE
Example event data values and properties
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 0.0 in stage 38.0 (TID 146)
javaThreadId long
1711
osName string
Executor task launch worker for task 0.0 in stage 38.0 (TID 146)
osThreadId long
4234
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
15
lineNumber int
5053
method Method
descriptor string
(Ljava/lang/String;ID[DII[DII)V
hidden boolean
false
modifiers int
4
name string
dsyrK
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
dev/ludovic/netlib/blas/Java8BLAS
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
dev/ludovic/netlib/blas
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
448335476092
state ThreadState
STATE_RUNNABLE

NativeMethodSample

default profiling startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Profiling

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

Missing in: graalvm_linux_native

Snapshot of a threads state when in native

Code Context

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

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

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

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

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

class OSThreadSampler : public 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;
  JfrStackTrace _stacktrace;
  bool _success;
};

static void write_native_event(JfrThreadSampleClosure& closure, JavaThread* jt) {
  EventNativeMethodSample *ev = closure.next_event_native();
  ev->set_starttime(JfrTicks::now());
  ev->set_sampledThread(JFR_THREAD_ID(jt));
  ev->set_state(java_lang_Thread::get_thread_status(jt->threadObj()));
}

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) {

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

    assert(_added_java > 0 && _added_java <= MAX_NR_OF_JAVA_SAMPLES, "invariant");
    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");
    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, Mutex::_no_safepoint_check_flag);

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_interval(JNIEnv* env, jobject jvm, jlong type, jlong intervalMillis))
  if (intervalMillis < 0) {
    intervalMillis = 0;
  }
  JfrEventId typed_event_id = (JfrEventId)type;
  assert(EventExecutionSample::eventId == typed_event_id || EventNativeMethodSample::eventId == typed_event_id, "invariant");
  if (intervalMillis > 0) {
    JfrEventSetting::set_enabled(typed_event_id, true); // ensure sampling event is enabled
  }
  if (EventExecutionSample::eventId == type) {
    JfrThreadSampling::set_java_sample_interval(intervalMillis);
  } else {
    JfrThreadSampling::set_native_sample_interval(intervalMillis);
  }
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_store_metadata_descriptor(JNIEnv* env, jobject jvm, jbyteArray descriptor))

Event configuration settings across JFR profiles
Configuration enabled period
default true 20 ms
profiling true 20 ms

Event fields with their types and descriptions
Field Type Description
sampledThread Thread Thread
stackTrace StackTrace Stack Trace
state ThreadState Thread State

Examples 3
Example event data values and properties
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
5014
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/io/FileDescriptor;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
24693016182
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
895
osName string
finagle/netty4-2-1
osThreadId long
3710
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
455355595420
state ThreadState
STATE_RUNNABLE
Example event data values and properties
sampledThread Thread
group ThreadGroup
name string
finagle/netty4/boss
parent ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
finagle/netty4/boss-1
javaThreadId long
875
osName string
finagle/netty4/boss-1
osThreadId long
3315
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
447582553366
state ThreadState
STATE_RUNNABLE

JVM: Runtime

BiasedLockRevocation

default profiling 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:

  bool is_bulk_rebias() const {
    return _bulk_rebias;
  }
};

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, VM_RevokeBias* 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(op->safepoint_id());
  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:

      // can come in with a CAS to steal the bias of an object that has a
      // stale epoch.
      ResourceMark rm;
      log_info(biasedlocking)("Revoking bias by walking my own stack:");
      EventBiasedLockSelfRevocation event;
      BiasedLocking::Condition cond = revoke_bias(obj(), false, false, (JavaThread*) THREAD, NULL);
      ((JavaThread*) THREAD)->set_cached_monitor_info(NULL);
      assert(cond == BIAS_REVOKED, "why not?");
      if (event.should_commit()) {
        post_self_revocation_event(&event, k);
      }
      return cond;
    } else {
      EventBiasedLockRevocation event;
      VM_RevokeBias revoke(&obj, (JavaThread*) THREAD);
      VMThread::execute(&revoke);
      if (event.should_commit() && revoke.status_code() != NOT_BIASED) {
        post_revocation_event(&event, k, &revoke);
      }
      return revoke.status_code();
    }
  }

  assert((heuristics == HR_BULK_REVOKE) ||
         (heuristics == HR_BULK_REBIAS), "?");

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

Event fields with their types and descriptions
Field Type Description
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

default profiling 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:

  virtual bool doit_prologue()   { return true; }

  virtual void doit() {
    _status_code = bulk_revoke_or_rebias_at_safepoint((*_obj)(), _bulk_rebias, _attempt_rebias_of_object, _requesting_thread);
    _safepoint_id = SafepointSynchronize::safepoint_id();
    clean_up_cached_monitor_info();
  }

  bool is_bulk_rebias() const {
    return _bulk_rebias;
  }
};

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, VM_RevokeBias* op) {
  assert(event != NULL, "invariant");
  assert(k != NULL, "invariant");
  assert(op != NULL, "invariant");

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

    if (mark->biased_locker() == THREAD &&
        prototype_header->bias_epoch() == mark->bias_epoch()) {
      // 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 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.
      // Also check the epoch because even if threads match, another thread
      // can come in with a CAS to steal the bias of an object that has a
      // stale epoch.
      ResourceMark rm;
      log_info(biasedlocking)("Revoking bias by walking my own stack:");
      EventBiasedLockSelfRevocation event;
      BiasedLocking::Condition cond = revoke_bias(obj(), false, false, (JavaThread*) THREAD, NULL);
      ((JavaThread*) THREAD)->set_cached_monitor_info(NULL);
      assert(cond == BIAS_REVOKED, "why not?");
      if (event.should_commit()) {
        post_self_revocation_event(&event, k);
      }
      return cond;
    } else {
      EventBiasedLockRevocation event;
      VM_RevokeBias revoke(&obj, (JavaThread*) THREAD);
      VMThread::execute(&revoke);

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

Event fields with their types and descriptions
Field Type Description
lockClass Class Lock Class Class of object whose biased lock was revoked

BiasedLockClassRevocation

default profiling 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, VM_RevokeBias* 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(op->safepoint_id());
  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();
}

BiasedLocking::Condition BiasedLocking::revoke_and_rebias(Handle obj, bool attempt_rebias, TRAPS) {

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

    } else {
      EventBiasedLockRevocation event;
      VM_RevokeBias revoke(&obj, (JavaThread*) THREAD);
      VMThread::execute(&revoke);
      if (event.should_commit() && revoke.status_code() != NOT_BIASED) {
        post_revocation_event(&event, k, &revoke);
      }
      return revoke.status_code();
    }
  }

  assert((heuristics == HR_BULK_REVOKE) ||
         (heuristics == HR_BULK_REBIAS), "?");
  EventBiasedLockClassRevocation event;
  VM_BulkRevokeBias bulk_revoke(&obj, (JavaThread*) THREAD,
                                (heuristics == HR_BULK_REBIAS),
                                attempt_rebias);
  VMThread::execute(&bulk_revoke);
  if (event.should_commit()) {
    post_class_revocation_event(&event, obj->klass(), &bulk_revoke);
  }
  return bulk_revoke.status_code();
}

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

Event fields with their types and descriptions
Field Type Description
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

default profiling startTime eventThread stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime

Activation of Reserved Stack Area caused by stack overflow with ReservedStackAccess annotated method in call stack

Code Context

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

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

        for (ScopeDesc *sd = nm->scope_desc_near(fr.pc()); sd != 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
default true true
profiling true true

Event fields with their types and descriptions
Field Type Description
method Method Java Method

SafepointBegin

default profiling startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime / Safepoint

Safepointing begin

Code Context

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

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

static void post_safepoint_begin_event(EventSafepointBegin& event,
                                       uint64_t safepoint_id,
                                       int thread_count,
                                       int critical_thread_count) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.set_totalThreadCount(thread_count);
    event.set_jniCriticalThreadCount(critical_thread_count);
    event.commit();
  }
}

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

    Interpreter::notice_safepoints();

    // Make polling safepoint aware
    guarantee (!PageArmed, "invariant") ;
    PageArmed = true;
    os::make_polling_page_unreadable();
  }
}

// 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
default true 10 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
safepointId ulong Safepoint Identifier
totalThreadCount int Total Threads The total number of threads at the start of safe point
jniCriticalThreadCount int JNI Critical Threads The number of threads in JNI critical sections

Examples 3
Example event data values and properties
jniCriticalThreadCount int
0
safepointId ulong
21
startTime long: millis
777360519
totalThreadCount int
25
Example event data values and properties
jniCriticalThreadCount int
0
safepointId ulong
539
startTime long: millis
476310881862
totalThreadCount int
69
Example event data values and properties
jniCriticalThreadCount int
0
safepointId ulong
1604
startTime long: millis
461763804953
totalThreadCount int
299

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
  if (safepoint_limit_time != 0) {

Event configuration settings across JFR profiles
Configuration enabled threshold
default false 10 ms
profiling false 0 ms

Event fields with their types and descriptions
Field Type Description
safepointId ulong Safepoint Identifier
initialThreadCount int Initial Threads The number of threads running at the beginning of state check
runningThreadCount int Running Threads The number of threads still running
iterations int Iterations Number of state check iterations

Examples 3
Example event data values and properties
initialThreadCount int
1
iterations int
3
runningThreadCount int
0
safepointId ulong
501
startTime long: millis
448953997645
Example event data values and properties
initialThreadCount int
2
iterations int
87
runningThreadCount int
0
safepointId ulong
1565
startTime long: millis
454900066345
Example event data values and properties
initialThreadCount int
2
iterations int
3
runningThreadCount int
0
safepointId ulong
47
startTime long: millis
1581986134

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
default false 10 ms
profiling false 0 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:

    AbstractGangTask("Parallel Safepoint Cleanup"),
    _subtasks(SafepointSynchronize::SAFEPOINT_CLEANUP_NUM_TASKS),
    _cleanup_threads_cl(ParallelSPCleanupThreadClosure(counters)),
    _num_workers(num_workers),
    _counters(counters) {}

  void work(uint worker_id) {
    uint64_t safepoint_id = SafepointSynchronize::safepoint_id();
    // All threads deflate monitors and mark nmethods (if necessary).
    Threads::possibly_parallel_threads_do(true, &_cleanup_threads_cl);

    if (_subtasks.try_claim_task(SafepointSynchronize::SAFEPOINT_CLEANUP_DEFLATE_MONITORS)) {
      const char* name = "deflating global idle monitors";
      EventSafepointCleanupTask event;
      TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
      ObjectSynchronizer::deflate_idle_monitors(_counters);

      post_safepoint_cleanup_task_event(event, safepoint_id, name);
    }

    if (_subtasks.try_claim_task(SafepointSynchronize::SAFEPOINT_CLEANUP_UPDATE_INLINE_CACHES)) {
      const char* name = "updating inline caches";
      EventSafepointCleanupTask event;
      TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
      InlineCacheBuffer::update_inline_caches();

      post_safepoint_cleanup_task_event(event, safepoint_id, name);
    }

    if (_subtasks.try_claim_task(SafepointSynchronize::SAFEPOINT_CLEANUP_COMPILATION_POLICY)) {
      const char* name = "compilation policy safepoint handler";
      EventSafepointCleanupTask event;
      TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
      CompilationPolicy::policy()->do_safepoint_work();

      post_safepoint_cleanup_task_event(event, safepoint_id, name);
    }

    if (_subtasks.try_claim_task(SafepointSynchronize::SAFEPOINT_CLEANUP_SYMBOL_TABLE_REHASH)) {
      if (SymbolTable::needs_rehashing()) {
        const char* name = "rehashing symbol table";
        EventSafepointCleanupTask event;
        TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
        SymbolTable::rehash_table();

        post_safepoint_cleanup_task_event(event, safepoint_id, name);
      }
    }

    if (_subtasks.try_claim_task(SafepointSynchronize::SAFEPOINT_CLEANUP_STRING_TABLE_REHASH)) {
      if (StringTable::needs_rehashing()) {
        const char* name = "rehashing string table";
        EventSafepointCleanupTask event;
        TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
        StringTable::rehash_table();

        post_safepoint_cleanup_task_event(event, safepoint_id, name);
      }
    }

    if (_subtasks.try_claim_task(SafepointSynchronize::SAFEPOINT_CLEANUP_CLD_PURGE)) {
      if (ClassLoaderDataGraph::should_purge_and_reset()) {
        // CMS delays purging the CLDG until the beginning of the next safepoint and to
        // make sure concurrent sweep is done
        const char* name = "purging class loader data graph";
        EventSafepointCleanupTask event;
        TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
        ClassLoaderDataGraph::purge();

        post_safepoint_cleanup_task_event(event, safepoint_id, name);
      }
    }

    if (_subtasks.try_claim_task(SafepointSynchronize::SAFEPOINT_CLEANUP_SYSTEM_DICTIONARY_RESIZE)) {
      if (Dictionary::does_any_dictionary_needs_resizing()) {
        const char* name = "resizing system dictionaries";
        EventSafepointCleanupTask event;
        TraceTime timer(name, TRACETIME_LOG(Info, safepoint, cleanup));
        ClassLoaderDataGraph::resize_dictionaries();

        post_safepoint_cleanup_task_event(event, safepoint_id, name);
      }
    }

    if (_subtasks.try_claim_task(SafepointSynchronize::SAFEPOINT_CLEANUP_REQUEST_OOPSTORAGE_CLEANUP)) {
      // Don't bother reporting event or time for this very short operation.
      // To have any utility we'd also want to report whether needed.
      OopStorage::trigger_cleanup_if_needed();

Event configuration settings across JFR profiles
Configuration enabled threshold
default false 10 ms
profiling false 0 ms

Event fields with their types and descriptions
Field Type Description
safepointId ulong Safepoint Identifier
name string Task Name The task name

SafepointEnd

startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime / Safepoint

Safepointing end

Code Context

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

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

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
default false 10 ms
profiling false 0 ms

Event fields with their types and descriptions
Field Type Description
safepointId ulong Safepoint Identifier

Examples 3
Example event data values and properties
safepointId ulong
531
startTime long: millis
466441355963
Example event data values and properties
safepointId ulong
1601
startTime long: millis
461755460081
Example event data values and properties
safepointId ulong
114
startTime long: millis
2377762716

ExecuteVMOperation

default profiling startTime duration eventThread 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime

Execution of a VM Operation

Code Context

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

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

  // otherwise we will hang, since there is no one can end the safepoint.

  // 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(event->should_commit(), "invariant");
  assert(op != NULL, "invariant");
  const bool is_concurrent = op->evaluate_concurrently();
  const bool evaluate_at_safepoint = op->evaluate_at_safepoint();
  event->set_operation(op->type());
  event->set_safepoint(evaluate_at_safepoint);
  event->set_blocking(!is_concurrent);
  // Only write caller thread information for non-concurrent vm operations.
  // For concurrent vm operations, the thread id is set to 0 indicating thread is unknown.
  // This is because the caller thread could have exited already.

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

  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->evaluation_mode());

    EventExecuteVMOperation event;
    op->evaluate();
    if (event.should_commit()) {
      post_vm_operation_event(&event, op);
    }

    HOTSPOT_VMOPS_END(
                     (char *) op->name(), strlen(op->name()),
                     op->evaluation_mode());
  }

  // Last access of info in _cur_vm_operation!

Event configuration settings across JFR profiles
Configuration enabled threshold
default true 10 ms
profiling true 0 ms

Event fields with their types and descriptions
Field Type Description
operation VMOperationType Operation
safepoint boolean At Safepoint If the operation 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
JFR Periodic Tasks
javaThreadId long
23
osName string
JFR Periodic Tasks
osThreadId long
2556
virtual boolean
false
operation VMOperationType
ClassLoaderStatsOperation
safepoint boolean
true
safepointId ulong
1561
startTime long: millis
454653354781
Example event data values and properties
blocking boolean
true
caller Thread
group ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
JFR Recorder Thread
javaThreadId long
18
osName string
JFR Recorder Thread
osThreadId long
2165
virtual boolean
false
operation VMOperationType
JFRSafepointWrite
safepoint boolean
true
safepointId ulong
498
startTime long: millis
447483379494
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
5014
virtual boolean
false
operation VMOperationType
HeapIterateOperation
safepoint boolean
true
safepointId ulong
7
startTime long: millis
375526192

Shutdown

default profiling startTime eventThread stackTrace 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime

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

Missing in: graalvm_linux_native

JVM shutting down

Code Context

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

src/hotspot/share/utilities/vmError.cpp:

      show_message_box(buffer, sizeof(buffer));

      // User has asked JVM to abort. Reset ShowMessageBoxOnError so the
      // WatcherThread can kill JVM if the error handler hangs.
      ShowMessageBoxOnError = false;
    }

    os::check_dump_limit(buffer, sizeof(buffer));

    // reset signal handlers or exception filter; make sure recursive crashes
    // are handled properly.
    reset_signal_handlers();

    EventShutdown e;
    if (e.should_commit()) {
      e.set_reason("VM Error");
      e.commit();
    }

    JFR_ONLY(Jfr::on_vm_shutdown(true);)

  } else {
    // If UseOsErrorReporting we call this for each level of the call stack
    // while searching for the exception handler.  Only the first level needs
    // to be reported.

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

  HandleMark hm(THREAD);
  const char* temp_dir = os::get_temp_directory();
  Handle h = java_lang_String::create_from_platform_dependent_str(temp_dir, CHECK_NULL);
  return (jstring) JNIHandles::make_local(env, h());
JVM_END


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

extern volatile jint vm_created;

JVM_ENTRY_NO_ENV(void, JVM_BeforeHalt())
  JVMWrapper("JVM_BeforeHalt");
  EventShutdown event;
  if (event.should_commit()) {
    event.set_reason("Shutdown requested from Java");
    event.commit();
  }
JVM_END


JVM_ENTRY_NO_ENV(void, JVM_Halt(jint code))
  before_exit(thread);
  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,
      // and wait as a suspend-equivalent condition.
      nu.wait(0, Mutex::_as_suspend_equivalent_flag);
  }

  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();

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

Event fields with their types and descriptions
Field Type Description
reason string Reason Reason for JVM shutdown

Examples 3
Example event data values and properties
reason string
No remaining non-daemon Java threads
stackTrace StackTrace
null
startTime long: millis
500177444641
Example event data values and properties
reason string
No remaining non-daemon Java threads
stackTrace StackTrace
null
startTime long: millis
510390931826
Example event data values and properties
reason string
No remaining non-daemon Java threads
stackTrace StackTrace
null
startTime long: millis
25440309651

SymbolTableStatistics

default 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
default true 10 s
profiling true 10 s

Event fields with their types and descriptions
Field Type Description
bucketCount ulong Bucket Count Number of buckets
entryCount ulong Entry Count Number of all entries
totalFootprint ulong: bytes Total Footprint Total memory footprint (the table itself plus all of the entries)
bucketCountMaximum ulong Maximum Bucket Count The maximum bucket length (entries in a single bucket)
bucketCountAverage float Average Bucket Count The average bucket length
bucketCountVariance float Bucket Count Variance How far bucket lengths are spread out from their average value
bucketCountStandardDeviation float Bucket Count Standard Deviation How far bucket lengths are spread out from their mean (expected) value
insertionRate float Insertion Rate How many items were added since last event (per second)
removalRate float Removal Rate How many items were removed since last event (per second)

Examples 3
Example event data values and properties
bucketCount ulong
131072
bucketCountAverage float
4.9328766
bucketCountMaximum ulong
17
bucketCountStandardDeviation float
2.2248921
bucketCountVariance float
4.9501452
entryCount ulong
646562
insertionRate float
375.99625
removalRate float
4667.4233
startTime long: millis
509467876278
totalFootprint ulong: bytes
71806456
Example event data values and properties
bucketCount ulong
32768
bucketCountAverage float
1.1372375
bucketCountMaximum ulong
7
bucketCountStandardDeviation float
1.0593047
bucketCountVariance float
1.1221266
entryCount ulong
37265
insertionRate float
41.447773
removalRate float
41.54507
startTime long: millis
20865406401
totalFootprint ulong: bytes
2451768
Example event data values and properties
bucketCount ulong
131072
bucketCountAverage float
4.9332733
bucketCountMaximum ulong
17
bucketCountStandardDeviation float
2.226176
bucketCountVariance float
4.9558597
entryCount ulong
646614
insertionRate float
973.59607
removalRate float
4163.1953
startTime long: millis
495898975221
totalFootprint ulong: bytes
71816936

StringTableStatistics

default 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
default true 10 s
profiling true 10 s

Event fields with their types and descriptions
Field Type Description
bucketCount ulong Bucket Count Number of buckets
entryCount ulong Entry Count Number of all entries
totalFootprint ulong: bytes Total Footprint Total memory footprint (the table itself plus all of the entries)
bucketCountMaximum ulong Maximum Bucket Count The maximum bucket length (entries in a single bucket)
bucketCountAverage float Average Bucket Count The average bucket length
bucketCountVariance float Bucket Count Variance How far bucket lengths are spread out from their average value
bucketCountStandardDeviation float Bucket Count Standard Deviation How far bucket lengths are spread out from their mean (expected) value
insertionRate float Insertion Rate How many items were added since last event (per second)
removalRate float Removal Rate How many items were removed since last event (per second)

Examples 3
Example event data values and properties
bucketCount ulong
65536
bucketCountAverage float
1.7944336
bucketCountMaximum ulong
11
bucketCountStandardDeviation float
1.3416739
bucketCountVariance float
1.8000886
entryCount ulong
117600
insertionRate float
137.96802
removalRate float
6.8462386
startTime long: millis
455890147132
totalFootprint ulong: bytes
12825360
Example event data values and properties
bucketCount ulong
65536
bucketCountAverage float
0.09992981
bucketCountMaximum ulong
3
bucketCountStandardDeviation float
0.3163474
bucketCountVariance float
0.10007568
entryCount ulong
6549
insertionRate float
23.93327
removalRate float
0.09728972
startTime long: millis
20867505968
totalFootprint ulong: bytes
1039912
Example event data values and properties
bucketCount ulong
131072
bucketCountAverage float
0.9037628
bucketCountMaximum ulong
9
bucketCountStandardDeviation float
0.9556673
bucketCountVariance float
0.91330004
entryCount ulong
118458
insertionRate float
112.68368
removalRate float
2.5040817
startTime long: millis
509506788087
totalFootprint ulong: bytes
13540712

PlaceholderTableStatistics

default 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
default true 10 s
profiling true 10 s

Event fields with their types and descriptions
Field Type Description
bucketCount ulong Bucket Count Number of buckets
entryCount ulong Entry Count Number of all entries
totalFootprint ulong: bytes Total Footprint Total memory footprint (the table itself plus all of the entries)
bucketCountMaximum ulong Maximum Bucket Count The maximum bucket length (entries in a single bucket)
bucketCountAverage float Average Bucket Count The average bucket length
bucketCountVariance float Bucket Count Variance How far bucket lengths are spread out from their average value
bucketCountStandardDeviation float Bucket Count Standard Deviation How far bucket lengths are spread out from their mean (expected) value
insertionRate float Insertion Rate How many items were added since last event (per second)
removalRate float Removal Rate How many items were removed since last event (per second)

LoaderConstraintsTableStatistics

default 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
default true 10 s
profiling true 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

default 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
default true 10 s
profiling true 10 s

Event fields with their types and descriptions
Field Type Description
bucketCount ulong Bucket Count Number of buckets
entryCount ulong Entry Count Number of all entries
totalFootprint ulong: bytes Total Footprint Total memory footprint (the table itself plus all of the entries)
bucketCountMaximum ulong Maximum Bucket Count The maximum bucket length (entries in a single bucket)
bucketCountAverage float Average Bucket Count The average bucket length
bucketCountVariance float Bucket Count Variance How far bucket lengths are spread out from their average value
bucketCountStandardDeviation float Bucket Count Standard Deviation How far bucket lengths are spread out from their mean (expected) value
insertionRate float Insertion Rate How many items were added since last event (per second)
removalRate float Removal Rate How many items were removed since last event (per second)

ThreadDump

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

Category: Java Virtual Machine / Runtime

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

Missing in: graalvm_linux_native

Code Context

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

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

  Thread* THREAD = Thread::current();
  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
default true everyChunk
profiling true 60 s

Event fields with their types and descriptions
Field Type Description
result string Thread Dump

Examples 3
Example event data values and properties
result string
2026-09-13 00:33:55 Full thread dump OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x000055ffb54d2f60, length=52, elements={ 0x00007f7b84053be0, 0x00007f7b840ca9b0, 0x00007f7b840cc5a0, 0x00007f7b840ce5e0, 0x00007f7b840d02c0, 0x00007f7b840d1…
startTime long: millis
484226807537
Example event data values and properties
result string
2026-09-08 12:51:50 Full thread dump OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x0000564e7f24e920, length=299, elements={ 0x00007fe43c053c00, 0x00007fe43c141b20, 0x00007fe43c143870, 0x00007fe43c1457b0, 0x00007fe43c1474c0, 0x00007fe43c14…
startTime long: millis
461372835532
Example event data values and properties
result string
2026-09-08 12:52:53 Full thread dump OpenJDK 64-Bit Server VM (25.0.4.1+1-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x00007fa9c94d87d0, length=26, elements={ 0x00007fa9c8055900, 0x00007fa9c8154950, 0x00007fa9c8156810, 0x00007fa9c8158c80, 0x00007fa9c815abc0, 0x00007fa9c815c…
startTime long: millis
10588931653

NativeLibrary

default profiling startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime

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

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized 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
default true everyChunk
profiling true everyChunk

Event fields with their types and descriptions
Field Type Description
name string Name
baseAddress ulong: address Base Address Starting address of the module
topAddress ulong: address Top Address Ending address of the module

Examples 3
Example event data values and properties
baseAddress ulong: address
140618303717376
name string
/opt/hostedtoolcache/Java_SapMachine_jdk/25.0.4-1/x64/lib/libmanagement_ext.so
startTime long: millis
453049939224
topAddress ulong: address
140618303750144
Example event data values and properties
baseAddress ulong: address
140367300984832
name string
/opt/hostedtoolcache/Java_SapMachine_jdk/25.0.4-1/x64/lib/libjava.so
startTime long: millis
15507239376
topAddress ulong: address
140367301128192
Example event data values and properties
baseAddress ulong: address
140167903969280
name string
/tmp/libzstd-jni-1.5.6-711930390467755450569.so
startTime long: millis
447754284306
topAddress ulong: address
140167908163584

ModuleRequire

default profiling startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime / Modules

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

Missing in: graalvm_linux_native

A directed edge representing a dependency

Code Context

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

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

   ModuleDependencyClosure(const ModuleEntry* module, EventFunc ef) : ModuleEventCallbackClosure(ef), _module(module) {}
   void do_module(ModuleEntry* entry);
};

class ModuleExportClosure : public ModuleEventCallbackClosure {
 private:
  const PackageEntry* const _package;
 public:
  ModuleExportClosure(const PackageEntry* pkg, EventFunc ef) : ModuleEventCallbackClosure(ef), _package(pkg) {}
  void do_module(ModuleEntry* entry);
};

static void write_module_dependency_event(const void* from_module, const ModuleEntry* to_module) {
  EventModuleRequire event(UNTIMED);
  event.set_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
default true endChunk
profiling true endChunk

Event fields with their types and descriptions
Field Type Description
source Module Source Module
requiredModule Module Required Module

Examples 3
Example event data values and properties
requiredModule Module
classLoader ClassLoader
name string
platform
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$PlatformClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
jrt:/java.compiler
name string
java.compiler
version string
25.0.4.1
source Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
jrt:/jdk.compiler
name string
jdk.compiler
version string
25.0.4.1
startTime long: millis
454658652535
Example event data values and properties
requiredModule Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
jrt:/jdk.internal.md
name string
jdk.internal.md
version string
25.0.4.1
source Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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.javadoc
name string
jdk.javadoc
version string
25.0.4.1
startTime long: millis
7832187786
Example event data values and properties
requiredModule Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
jrt:/jdk.internal.opt
name string
jdk.internal.opt
version string
25.0.4.1
source Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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.jartool
name string
jdk.jartool
version string
25.0.4.1
startTime long: millis
448951600733

ModuleExport

default profiling startTime every chunk 11 17 21 25 27 28

Category: Java Virtual Machine / Runtime / Modules

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

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized 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
default true endChunk
profiling true endChunk

Event fields with their types and descriptions
Field Type Description
exportedPackage Package Exported Package
targetModule Module Target Module Module to which the package is qualifiedly exported. If null or N/A, the package is unqualifiedly exported

Examples 3
Example event data values and properties
exportedPackage Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.management
name string
java.management
version string
25.0.4.1
name string
com/sun/jmx/remote/security
startTime long: millis
7832224796
targetModule Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.management.rmi
name string
java.management.rmi
version string
25.0.4.1
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.base
name string
java.base
version string
25.0.4.1
name string
javax/crypto/spec
startTime long: millis
448951948567
targetModule Module
null
Example event data values and properties
exportedPackage Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/hadoop/security
startTime long: millis
454658924545
targetModule Module
null

Java Application

ThreadStart

default profiling startTime eventThread stackTrace 11 17 21 25 27 28

Category: Java Application

Code Context

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

src/hotspot/share/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:

  if (native_thread->osthread() == NULL) {
    // 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 (JfrRecorder::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");
  if (JfrRecorder::is_recording()) {
    if (t->is_Java_thread()) {
      send_java_thread_start_event((JavaThread*)t);

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

Event fields with their types and descriptions
Field Type Description
thread Thread New Java Thread
parentThread Thread Parent Java Thread

Examples 3
Example event data values and properties
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
5014
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
41
lineNumber int
550
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
socketIO
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
4353969484
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Thread-63
javaThreadId long
120
osName string
Thread-63
osThreadId long
5141
virtual boolean
false
Example event data values and properties
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
2535
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
10
lineNumber int
32
method Method
descriptor string
(Ljava/lang/Runnable;)V
hidden boolean
false
modifiers int
1
name string
execute
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
io/netty/util/concurrent/ThreadPerTaskExecutor
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/util/concurrent
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
480380684038
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
rpc-client-1-1
javaThreadId long
1951
osName string
rpc-client-1-1
osThreadId long
4881
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
2151
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
10
lineNumber int
32
method Method
descriptor string
(Ljava/lang/Runnable;)V
hidden boolean
false
modifiers int
1
name string
execute
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
io/netty/util/concurrent/ThreadPerTaskExecutor
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/util/concurrent
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
475261103869
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
rpc-server-4-3
javaThreadId long
1929
osName string
rpc-server-4-3
osThreadId long
4465
virtual boolean
false

ThreadEnd

default profiling startTime eventThread 11 17 21 25 27 28

Category: Java Application

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

Missing in: graalvm_linux_native

Code Context

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

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

      send_java_thread_start_event((JavaThread*)t);
    }
  }
  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(JfrThreadLocal* tl, Thread* t) {
  assert(tl != NULL, "invariant");
  assert(t != NULL, "invariant");
  assert(Thread::current() == t, "invariant");
  assert(!tl->is_dead(), "invariant");

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

#if INCLUDE_JVMCI
  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();)

  // Stop the WatcherThread. We do this before disenrolling various
  // PeriodicTasks to reduce the likelihood of races.
  if (PeriodicTask::num_tasks() > 0) {
    WatcherThread::stop();

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

Event fields with their types and descriptions
Field Type Description
thread Thread Java Thread

Examples 3
Example event data values and properties
startTime long: millis
480366244446
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-storage-async-thread-pool-22
javaThreadId long
1773
osName string
block-manager-storage-async-thread-pool-22
osThreadId long
4691
virtual boolean
false
Example event data values and properties
startTime long: millis
475228342512
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
SparkUI-1688
javaThreadId long
1688
osName string
SparkUI-1688
osThreadId long
4207
virtual boolean
false
Example event data values and properties
startTime long: millis
1108512889
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
HandshakeCompletedNotify-Thread
javaThreadId long
54
osName string
HandshakeCompletedNotify-Thread
osThreadId long
5055
virtual boolean
false

ThreadSleep

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

Category: Java Application

Code Context

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

src/hotspot/share/prims/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))
  JVMWrapper("JVM_Yield");
  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))
  JVMWrapper("JVM_Sleep");

  if (millis < 0) {
    THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "timeout value is negative");
  }

  if (Thread::is_interrupted (THREAD, 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 (os::sleep(thread, millis, true) == OS_INTRPT) {
      // 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
default true true 20 ms
profiling true true 10 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$Worker
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/util
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
453882414079
time long: millis
10000000
Example event data values and properties
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
12
lineNumber int
49
method Method
descriptor string
()V
hidden boolean
false
modifiers int
4106
name string
lambda$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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
770929097
time long: millis
5000000
Example event data values and properties
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
91
lineNumber int
598
method Method
descriptor string
()J
hidden boolean
false
modifiers int
2
name string
waitForNextTick
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
18
name string
io/netty/util/HashedWheelTimer$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
448360450446
time long: millis
7000000

ThreadPark

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

Category: Java Application

Code Context

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

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

} UNSAFE_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(x, addr, e) == e;
  } else {
    assert_field_offset_sane(p, offset);
    return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e) == 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");
  assert(event->should_commit(), "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
default true true 20 ms
profiling true true 10 ms

Event fields with their types and descriptions
Field Type Description
parkedClass Class Class Parked On
timeout long: nanos Park Timeout
until long: epochmillis Park Until
address ulong: address Address of Object Parked

Examples 3
Example event data values and properties
address ulong: address
30389543984
parkedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionObject
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent/locks
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
type FrameType
Native
…
truncated boolean
false
startTime long: millis
445641742401
timeout long: nanos
59999999970
until long: epochmillis
-9223372036854775808
Example event data values and properties
address ulong: address
30362878480
parkedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionObject
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent/locks
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
type FrameType
Native
…
truncated boolean
false
startTime long: millis
452948726203
timeout long: nanos
-9223372036854775808
until long: epochmillis
-9223372036854775808
Example event data values and properties
address ulong: address
0
parkedClass Class
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
type FrameType
Native
…
truncated boolean
false
startTime long: millis
591688476
timeout long: nanos
4963513
until long: epochmillis
-9223372036854775808

JavaMonitorEnter

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

Category: Java Application

Code Context

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

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

  assert(_owner != Self, "invariant");
  assert(_succ != Self, "invariant");
  assert(Self->is_Java_thread(), "invariant");
  JavaThread * jt = (JavaThread *) Self;
  assert(!SafepointSynchronize::is_at_safepoint(), "invariant");
  assert(jt->thread_state() != _thread_blocked, "invariant");
  assert(this->object() != NULL, "invariant");
  assert(_contentions >= 0, "invariant");

  // Prevent deflation at STW-time.  See deflate_idle_monitors() and is_busy().
  // Ensure the object-monitor relationship remains stable while there's contention.
  Atomic::inc(&_contentions);

  JFR_ONLY(JfrConditionalFlushWithStacktrace<EventJavaMonitorEnter> flush(jt);)
  EventJavaMonitorEnter event;
  if (event.should_commit()) {
    event.set_monitorClass(((oop)this->object())->klass());
    event.set_address((uintptr_t)(this->object_addr()));
  }

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

    Self->set_current_pending_monitor(this);

    DTRACE_MONITOR_PROBE(contended__enter, this, object(), jt);

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(Self);
  }
#endif

  for (;;) {
    assert(THREAD == _owner, "invariant");

    // release semantics: prior loads and stores from within the critical section
    // must not float (reorder) past the following store that drops the lock.
    // On SPARC that requires MEMBAR #loadstore|#storestore.
    // But of course in TSO #loadstore|#storestore is not required.

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 20 ms
profiling true true 10 ms

Event fields with their types and descriptions
Field Type Description
monitorClass Class Monitor Class
previousOwner Thread Previous Monitor Owner
address ulong: address Monitor Address

Examples 3
Example event data values and properties
address ulong: address
94556810078336
monitorClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/rpc/netty/Dispatcher
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/rpc/netty
previousOwner Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 2.0 in stage 38.0 (TID 148)
javaThreadId long
1712
osName string
Executor task launch worker for task 2.0 in stage 38.0 (TID 148)
osThreadId long
4235
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
4
lineNumber int
173
method Method
descriptor string
(Ljava/lang/String;Lorg/apache/spark/rpc/netty/InboxMessage;Lscala/Function1;)V
hidden boolean
false
modifiers int
2
name string
postMessage
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/rpc/netty/Dispatcher
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/rpc/netty
type FrameType
JIT compiled
…
truncated boolean
false
startTime long: millis
448391542294
Example event data values and properties
address ulong: address
94895150366080
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
1736
osName string
task-result-getter-3
osThreadId long
4653
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
768
method Method
descriptor string
(J)Z
hidden boolean
false
modifiers int
1
name string
canFetchMoreResults
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/TaskSetManager
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
454311338920
Example event data values and properties
address ulong: address
94795312341280
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
previousOwner Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
5014
virtual boolean
false
stackTrace StackTrace
null
startTime long: millis
1107904669

JavaMonitorWait

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

Category: Java Application

Waiting on a Java monitor

Code Context

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

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

        THROW(vmSymbols::java_lang_IllegalMonitorStateException());         \
      }                                                                     \
    }                                                                       \
  } while (false)

// check_slow() is a misnomer.  It's called to simply to throw an IMSX exception.
// TODO-FIXME: remove check_slow() -- it's likely dead.

void ObjectMonitor::check_slow(TRAPS) {
  assert(THREAD != _owner && !THREAD->is_lock_owned((address) _owner), "must not be owner");
  THROW_MSG(vmSymbols::java_lang_IllegalMonitorStateException(), "current thread not owner");
}

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");
  event->set_monitorClass(((oop)monitor->object())->klass());
  event->set_timeout(timeout);
  event->set_address((uintptr_t)monitor->object_addr());
  event->set_notifier(notifier_tid);
  event->set_timedOut(timedout);

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

//
// Note: a subset of changes to ObjectMonitor::wait()
// will need to be replicated in complete_exit
void ObjectMonitor::wait(jlong millis, bool interruptible, TRAPS) {
  Thread * const Self = THREAD;
  assert(Self->is_Java_thread(), "Must be Java thread!");
  JavaThread *jt = (JavaThread *)THREAD;

  assert(InitDone, "Unexpectedly not initialized");

  // Throw IMSX or IEX.
  CHECK_OWNER();

  EventJavaMonitorWait event;

  // check for a pending interrupt
  if (interruptible && Thread::is_interrupted(Self, 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(jt, 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
default true true 20 ms
profiling true true 10 ms

Event fields with their types and descriptions
Field Type Description
monitorClass Class Monitor Class Class of object waited on
notifier Thread Notifier Thread Notifying Thread
timeout long: millis Timeout Maximum wait time
timedOut boolean Timed Out Wait has been timed out
address ulong: address Monitor Address Address of object waited on

Examples 3
Example event data values and properties
address ulong: address
94895174441632
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
java/lang/ref/ReferenceQueue$Lock
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang/ref
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
453271935928
timedOut boolean
true
timeout long: millis
100
Example event data values and properties
address ulong: address
94556810601344
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
notifier Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 0.0 in stage 38.0 (TID 146)
javaThreadId long
1711
osName string
Executor task launch worker for task 0.0 in stage 38.0 (TID 146)
osThreadId long
4234
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
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
448482037769
timedOut boolean
false
timeout long: millis
0
Example event data values and properties
address ulong: address
94795309480480
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
notifier Thread
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
274
name string
wait0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Native
…
truncated boolean
false
startTime long: millis
1955946905
timedOut boolean
true
timeout long: millis
1

JavaMonitorInflate

profiling startTime duration eventThread stackTrace 11 17 21 25 27 28

Category: Java Application

Code Context

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

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

  if (log_is_enabled(Debug, monitorinflation)) {
    ls = &lsh_debug;
  } else if ((tally != 0 || inUseTally != 0) &&
             log_is_enabled(Info, monitorinflation)) {
    ls = &lsh_info;
  }
  if (ls != NULL) {
    ls->print_cr("omFlush: jt=" INTPTR_FORMAT ", free_monitor_tally=%d"
                 ", in_use_monitor_tally=%d" ", omFreeProvision=%d",
                 p2i(Self), tally, inUseTally, Self->omFreeProvision);
  }
}

static void post_monitor_inflate_event(EventJavaMonitorInflate* event,
                                       const oop obj,
                                       ObjectSynchronizer::InflateCause cause) {
  assert(event != NULL, "invariant");
  assert(event->should_commit(), "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

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

    return;
  }
  inflate(Thread::current(), obj, inflate_cause_vm_internal);
}

ObjectMonitor* ObjectSynchronizer::inflate(Thread * Self,
                                           oop object,
                                           const InflateCause cause) {
  // Inflate mutates the heap ...
  // Relaxing assertion for bug 6320749.
  assert(Universe::verify_in_progress() ||
         !SafepointSynchronize::is_at_safepoint(), "invariant");

  EventJavaMonitorInflate event;

  for (;;) {
    const markOop mark = object->mark();
    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
default false true 20 ms
profiling true true 10 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
33629833520
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
454876701568
Example event data values and properties
address ulong: address
30898345424
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
473195899460
Example event data values and properties
address ulong: address
30195380216
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
5771803533

ObjectAllocationInNewTLAB

profiling startTime eventThread stackTrace 11 17 21 25 27 28

Category: Java Application

Allocation in new Thread Local Allocation Buffer

Code Context

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

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

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

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

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default false true
profiling true 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
16
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[I
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
8
lineNumber int
340
method Method
descriptor string
()Ljdk/internal/access/JavaSecurityPropertiesAccess;
hidden boolean
false
modifiers int
9
name string
getJavaSecurityPropertiesAccess
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
jdk/internal/access/SharedSecrets
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/access
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
375717969
tlabSize ulong: bytes
535104
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
1
name string
org/apache/spark/mllib/linalg/DenseVector
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/mllib/linalg
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
12
lineNumber int
500
method Method
descriptor string
(Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
false
modifiers int
8
name string
allocateInstance
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/invoke/DirectMethodHandle
package Package
exported boolean
true
module Module
classLoader ClassLoader
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
type FrameType
Inlined
…
truncated boolean
false
startTime long: millis
453332151620
tlabSize ulong: bytes
1048576
Example event data values and properties
allocationSize ulong: bytes
16
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
Inlined
…
truncated boolean
false
startTime long: millis
447514834805
tlabSize ulong: bytes
318128

ObjectAllocationOutsideTLAB

profiling 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, Thread* thread) {
  JFR_ONLY(JfrAllocationTracer tracer(obj, alloc_size, 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, Thread* thread) {
  JFR_ONLY(JfrAllocationTracer tracer(obj, alloc_size, thread);)
  EventObjectAllocationInNewTLAB event;
  if (event.should_commit()) {

Event configuration settings across JFR profiles
Configuration enabled stackTrace
default false true
profiling true 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
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
448111302139
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
561104216
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
453545589640

SocketRead

default profiling startTime duration stackTrace 11 17 21 25 27 28

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/internal/instrument/JDKEvents.java:

public final class JDKEvents {

    private static final Class<?>[] mirrorEventClasses = {
        SecurityPropertyModificationEvent.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.SecurityPropertyModificationEvent.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/SocketChannelImplInstrumentor.java:

 * See {@link JITracer} for an explanation of this code.
 */
@JIInstrumentationTarget("sun.nio.ch.SocketChannelImpl")
final class SocketChannelImplInstrumentor {

    private SocketChannelImplInstrumentor() {
    }

    private InetSocketAddress remoteAddress;

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public int read(ByteBuffer dst) throws IOException {
        SocketReadEvent event = SocketReadEvent.EVENT.get();
        if (!event.isEnabled()) {
            return read(dst);
        }
        int bytesRead = 0;
        try {
            event.begin();
            bytesRead = read(dst);
        } finally {
            event.end();
            if (event.shouldCommit())  {
                String hostString  = remoteAddress.getAddress().toString();

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

                event.timeout   = 0;

                event.commit();
                event.reset();
            }
        }
        return bytesRead;
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public long read(ByteBuffer[] dsts, int offset, int length) throws IOException {
        SocketReadEvent event = SocketReadEvent.EVENT.get();
        if(!event.isEnabled()) {
            return read(dsts, offset, length);
        }

        long bytesRead = 0;
        try {
            event.begin();
            bytesRead = read(dsts, offset, length);
        } finally {
            event.end();
            if (event.shouldCommit()) {

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

/**
 * See {@link JITracer} for an explanation of this code.
 */
@JIInstrumentationTarget("java.net.Socket$SocketInputStream")
final class SocketInputStreamInstrumentor {

    private SocketInputStreamInstrumentor() {
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public int read(byte b[], int off, int length) throws IOException {
        SocketReadEvent event = SocketReadEvent.EVENT.get();
        if (!event.isEnabled()) {
            return read(b, off, length);
        }
        int bytesRead = 0;
        try {
            event.begin();
            bytesRead = read(b, off, length);
        } finally {
            event.end();
            if (event.shouldCommit()) {
                InetAddress remote = parent.getInetAddress();

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 {

    public static final ThreadLocal<SocketReadEvent> EVENT =
        new ThreadLocal<>() {
            @Override protected SocketReadEvent initialValue() {
                return new SocketReadEvent();
            }
        };

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

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

    @Label("Remote Port")
    public int port;

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 20 ms
profiling true true 10 ms

Event fields with their types and descriptions
Field Type Description
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
42183
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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
3215793934
timeout long: millis
0
Example event data values and properties
address string
127.0.0.1
bytesRead long: bytes
64
endOfStream boolean
false
host string
127.0.0.1
port int
34267
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
31
lineNumber int
547
method Method
descriptor string
(I)V
hidden boolean
false
modifiers int
4106
name string
lambda$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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
2213874549
timeout long: millis
0
Example event data values and properties
address string
127.0.0.1
bytesRead long: bytes
64
endOfStream boolean
false
host string
127.0.0.1
port int
35823
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
31
lineNumber int
547
method Method
descriptor string
(I)V
hidden boolean
false
modifiers int
4106
name string
lambda$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
2502436869
timeout long: millis
0

SocketWrite

default profiling startTime duration stackTrace 11 17 21 25 27 28

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/internal/instrument/JDKEvents.java:

    private static final Class<?>[] mirrorEventClasses = {
        SecurityPropertyModificationEvent.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.SecurityPropertyModificationEvent.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/SocketChannelImplInstrumentor.java:

                event.timeout   = 0;

                event.commit();
                event.reset();
            }
        }
        return bytesRead;
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public int write(ByteBuffer buf) throws IOException {
        SocketWriteEvent event = SocketWriteEvent.EVENT.get();
        if (!event.isEnabled()) {
            return write(buf);
        }

        int bytesWritten = 0;
        try {
            event.begin();
            bytesWritten = write(buf);
        } finally {
            event.end();
            if (event.shouldCommit()) {

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

                event.port         = remoteAddress.getPort();
                event.bytesWritten = bytesWritten < 0 ? 0 : bytesWritten;

                event.commit();
                event.reset();
            }
        }
        return bytesWritten;
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public long write(ByteBuffer[] srcs, int offset, int length) throws IOException {
        SocketWriteEvent event = SocketWriteEvent.EVENT.get();
        if (!event.isEnabled()) {
            return write(srcs, offset, length);
        }
        long bytesWritten = 0;
        try {
            event.begin();
            bytesWritten = write(srcs, offset, length);
        } finally {
            event.end();
            if (event.shouldCommit()) {
                String hostString  = remoteAddress.getAddress().toString();

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

/**
 * See {@link JITracer} for an explanation of this code.
 */
@JIInstrumentationTarget("java.net.Socket$SocketOutputStream")
final class SocketOutputStreamInstrumentor {

    private SocketOutputStreamInstrumentor() {
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public void write(byte b[], int off, int len) throws IOException {
        SocketWriteEvent event = SocketWriteEvent.EVENT.get();
        if (!event.isEnabled()) {
            write(b, off, len);
            return;
        }
        int bytesWritten = 0;
        try {
            event.begin();
            write(b, off, len);
            bytesWritten = len;
        } finally {
            event.end() ;

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 {

    public static final ThreadLocal<SocketWriteEvent> EVENT =
        new ThreadLocal<>() {
            @Override protected SocketWriteEvent initialValue() {
                return new SocketWriteEvent();
            }
        };

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

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

    @Label("Remote Port")
    public int port;

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 20 ms
profiling true true 10 ms

Event fields with their types and descriptions
Field Type Description
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
47286
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
2624867489
Example event data values and properties
address string
127.0.0.1
bytesWritten long: bytes
64
host string
127.0.0.1
port int
51666
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
2075586082
Example event data values and properties
address string
127.0.0.1
bytesWritten long: bytes
64
host string
127.0.0.1
port int
45887
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
2239745583

JavaErrorThrow

default profiling 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
default true true
profiling true true

Event fields with their types and descriptions
Field Type Description
message string Message
thrownClass Class Class

Examples 3
Example event data values and properties
message string
'java.lang.Object java.lang.invoke.DirectMethodHandle$Holder.invokeSpecialIFC(java.lang.Object, java.lang.Object, java.lang.Object, int, java.lang.Object, java.lang.Object)'
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
16
lineNumber int
74
method Method
descriptor string
(Ljava/lang/String;)V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Error
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
type FrameType
Inlined
…
truncated boolean
true
startTime long: millis
487458211915
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/NoSuchMethodError
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang
Example event data values and properties
message string
'java.lang.Object java.lang.invoke.DirectMethodHandle$Holder.invokeStatic(java.lang.Object, java.lang.Object, java.lang.Object, java.lang.Object, int)'
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
432454417
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)'
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
false
startTime long: millis
490494165393
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/NoSuchMethodError
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/lang

JavaExceptionThrow

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
default false true
profiling 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
java.lang.reflect.InvocationTargetException
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
49
lineNumber int
313
method Method
descriptor string
(Ljava/lang/String;Ljava/lang/Throwable;)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
1306720426
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/ClassNotFoundException
package Package
exported boolean
true
module Module
classLoader ClassLoader
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
453968438191
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
448503230735
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

FileRead

default profiling 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/internal/instrument/JDKEvents.java:

public final class JDKEvents {

    private static final Class<?>[] mirrorEventClasses = {
        SecurityPropertyModificationEvent.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.SecurityPropertyModificationEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.X509CertificateEvent.class,

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

 * See {@link JITracer} for an explanation of this code.
 */
@JIInstrumentationTarget("java.io.RandomAccessFile")
final class RandomAccessFileInstrumentor {

    private RandomAccessFileInstrumentor() {
    }

    private String path;

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public int read() throws IOException {
        FileReadEvent event = FileReadEvent.EVENT.get();
        if (!event.isEnabled()) {
            return read();
        }
        int result = 0;
        try {
            event.begin();
            result = read();
            if (result < 0) {
                event.endOfFile = true;
            } else {
                event.bytesRead = 1;
            }
        } finally {
            event.path = path;
            event.commit();
            event.reset();
        }
        return result;
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public int read(byte b[]) throws IOException {
        FileReadEvent event = FileReadEvent.EVENT.get();
        if (!event.isEnabled()) {
            return read(b);
        }
        int bytesRead = 0;
        try {
            event.begin();
            bytesRead = read(b);
        } finally {
            if (bytesRead < 0) {
                event.endOfFile = true;
            } else {
                event.bytesRead = bytesRead;
            }
            event.path = path;
            event.commit();
            event.reset();
        }
        return bytesRead;
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public int read(byte b[], int off, int len) throws IOException {
        FileReadEvent event = FileReadEvent.EVENT.get();
        if (!event.isEnabled()) {
            return read(b, off, len);
        }
        int bytesRead = 0;
        try {
            event.begin();
            bytesRead = read(b, off, len);
        } finally {
            if (bytesRead < 0) {
                event.endOfFile = true;
            } else {

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

 * See {@link JITracer} for an explanation of this code.
 */
@JIInstrumentationTarget("java.io.FileInputStream")
final class FileInputStreamInstrumentor {

    private FileInputStreamInstrumentor() {
    }

    private String path;

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public int read() throws IOException {
        FileReadEvent event = FileReadEvent.EVENT.get();
        if (!event.isEnabled()) {
            return read();
        }
        int result = 0;
        try {
            event.begin();
            result = read();
            if (result < 0) {
                event.endOfFile = true;
            } else {
                event.bytesRead = 1;
            }
        } finally {
            event.path = path;
            event.commit();
            event.reset();
        }
        return result;
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public int read(byte b[]) throws IOException {
        FileReadEvent event = FileReadEvent.EVENT.get();
        if (!event.isEnabled()) {
            return read(b);
        }
        int bytesRead = 0;
        try {
            event.begin();
            bytesRead = read(b);
        } finally {
            if (bytesRead < 0) {
                event.endOfFile = true;
            } else {
                event.bytesRead = bytesRead;
            }
            event.path = path;
            event.commit();
            event.reset();
        }
        return bytesRead;
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public int read(byte b[], int off, int len) throws IOException {
        FileReadEvent event = FileReadEvent.EVENT.get();
        if (!event.isEnabled()) {
            return read(b, off, len);
        }
        int bytesRead = 0;
        try {
            event.begin();
            bytesRead = read(b, off, len);
        } finally {
            if (bytesRead < 0) {
                event.endOfFile = true;
            } else {

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

            event.begin();
            force(metaData);
        } finally {
            event.path = path;
            event.metaData = metaData;
            event.commit();
            event.reset();
        }
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public int read(ByteBuffer dst) throws IOException {
        FileReadEvent event = FileReadEvent.EVENT.get();
        if (!event.isEnabled()) {
            return read(dst);
        }
        int bytesRead = 0;
        try {
            event.begin();
            bytesRead = read(dst);
        } finally {
            if (bytesRead < 0) {
                event.endOfFile = true;
            } else {
                event.bytesRead = bytesRead;
            }
            event.path = path;
            event.commit();
            event.reset();
        }
        return bytesRead;
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public int read(ByteBuffer dst, long position) throws IOException {
        FileReadEvent event = FileReadEvent.EVENT.get();
        if (!event.isEnabled()) {
            return read(dst, position);
        }
        int bytesRead = 0;
        try {
            event.begin();
            bytesRead = read(dst, position);
        } finally {
            if (bytesRead < 0) {
                event.endOfFile = true;
            } else {
                event.bytesRead = bytesRead;
            }
            event.path = path;
            event.commit();
            event.reset();
        }
        return bytesRead;
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public long read(ByteBuffer[] dsts, int offset, int length) throws IOException {
        FileReadEvent event = FileReadEvent.EVENT.get();
        if (!event.isEnabled()) {
            return read(dsts, offset, length);
        }
        long bytesRead = 0;
        try {
            event.begin();
            bytesRead = read(dsts, offset, length);
        } finally {
            if (bytesRead < 0) {
                event.endOfFile = true;
            } else {

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 {

    public static final ThreadLocal<FileReadEvent> EVENT =
        new ThreadLocal<>() {
            @Override protected FileReadEvent initialValue() {
                return new FileReadEvent();
            }
        };

    @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
    public long bytesRead;

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 20 ms
profiling true true 10 ms

Event fields with their types and descriptions
Field Type Description
path string Path Full path of the file
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
85
endOfFile boolean
false
path string
/home/runner/work/jfrevents/jfrevents/.cache/jfr_sample_app.jar
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$Source
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/zip
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
384814947
Example event data values and properties
bytesRead long: bytes
8192
endOfFile boolean
false
path string
/tmp/jar_cache3220599901691524981.tmp
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
24
lineNumber int
1588
method Method
descriptor string
([BIIJ)I
hidden boolean
false
modifiers int
18
name string
readAt
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
java/util/zip/ZipFile$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
false
startTime long: millis
454314284016
Example event data values and properties
bytesRead long: bytes
30
endOfFile boolean
false
path string
/tmp/jar_cache2308870793994469680.tmp
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
43
lineNumber int
1575
method Method
descriptor string
([BIIJ)I
hidden boolean
false
modifiers int
18
name string
readFullyAt
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
JIT compiled
…
truncated boolean
false
startTime long: millis
448298343456

FileForce

default profiling 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/internal/instrument/JDKEvents.java:

public final class JDKEvents {

    private static final Class<?>[] mirrorEventClasses = {
        SecurityPropertyModificationEvent.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.SecurityPropertyModificationEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,

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

 * See {@link JITracer} for an explanation of this code.
 */
@JIInstrumentationTarget("sun.nio.ch.FileChannelImpl")
final class FileChannelImplInstrumentor {

    private FileChannelImplInstrumentor() {
    }

    private String path;

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public void force(boolean metaData) throws IOException {
        FileForceEvent event = FileForceEvent.EVENT.get();
        if (!event.isEnabled()) {
            force(metaData);
            return;
        }
        try {
            event.begin();
            force(metaData);
        } finally {
            event.path = path;
            event.metaData = metaData;
            event.commit();

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 {

    public static final ThreadLocal<FileForceEvent> EVENT =
        new ThreadLocal<>() {
            @Override protected FileForceEvent initialValue() {
                return new FileForceEvent();
            }
        };

    @Label("Path")
    @Description("Full path of the file")
    public String path;

    @Label("Update Metadata")
    @Description("Whether the file metadata is updated")
    public boolean metaData;

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 20 ms
profiling true true 10 ms

Event fields with their types and descriptions
Field Type Description
path string Path Full path of the file
metaData boolean Update Metadata Whether the file metadata is updated

Examples 3
Example event data values and properties
metaData boolean
true
path string
/tmp/jfr_sample13137898057837233450.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
2404467939
Example event data values and properties
metaData boolean
true
path string
/tmp/jfr_sample4646412869330140946.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
3454377715
Example event data values and properties
metaData boolean
true
path string
/tmp/jfr_sample7950200855328356358.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
1859164416

FileWrite

default profiling 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/internal/instrument/JDKEvents.java:

public final class JDKEvents {

    private static final Class<?>[] mirrorEventClasses = {
        SecurityPropertyModificationEvent.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.SecurityPropertyModificationEvent.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/FileOutputStreamInstrumentor.java:

 * See {@link JITracer} for an explanation of this code.
 */
@JIInstrumentationTarget("java.io.FileOutputStream")
final class FileOutputStreamInstrumentor {

    private FileOutputStreamInstrumentor() {
    }

    private String path;

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public void write(int b) throws IOException {
        FileWriteEvent event = FileWriteEvent.EVENT.get();
        if (!event.isEnabled()) {
            write(b);
            return;
        }
        try {
            event.begin();
            write(b);
            event.bytesWritten = 1;
        } finally {
            event.path = path;
            event.commit();
            event.reset();
        }
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public void write(byte b[]) throws IOException {
        FileWriteEvent event = FileWriteEvent.EVENT.get();
        if (!event.isEnabled()) {
            write(b);
            return;
        }
        try {
            event.begin();
            write(b);
            event.bytesWritten = b.length;
        } finally {
            event.path = path;
            event.commit();
            event.reset();
        }
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public void write(byte b[], int off, int len) throws IOException {
        FileWriteEvent event = FileWriteEvent.EVENT.get();
        if (!event.isEnabled()) {
            write(b, off, len);
            return;
        }
        try {
            event.begin();
            write(b, off, len);
            event.bytesWritten = len;
        } finally {
            event.path = path;
            event.commit();

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

            } else {
                event.bytesRead = bytesRead;
            }
            event.path = path;
            event.commit();
            event.reset();
        }
        return bytesRead;
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public void write(int b) throws IOException {
        FileWriteEvent event = FileWriteEvent.EVENT.get();
        if (!event.isEnabled()) {
            write(b);
            return;
        }
        try {
            event.begin();
            write(b);
            event.bytesWritten = 1;
        } finally {
            event.path = path;
            event.commit();
            event.reset();
        }
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public void write(byte b[]) throws IOException {
        FileWriteEvent event = FileWriteEvent.EVENT.get();
        if (!event.isEnabled()) {
            write(b);
            return;
        }
        try {
            event.begin();
            write(b);
            event.bytesWritten = b.length;
        } finally {
            event.path = path;
            event.commit();
            event.reset();
        }
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public void write(byte b[], int off, int len) throws IOException {
        FileWriteEvent event = FileWriteEvent.EVENT.get();
        if (!event.isEnabled()) {
            write(b, off, len);
            return;
        }
        try {
            event.begin();
            write(b, off, len);
            event.bytesWritten = len;
        } finally {
            event.path = path;
            event.commit();

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

            } else {
                event.bytesRead = bytesRead;
            }
            event.path = path;
            event.commit();
            event.reset();
        }
        return bytesRead;
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public int write(ByteBuffer src) throws IOException {
        FileWriteEvent event = FileWriteEvent.EVENT.get();
        if (!event.isEnabled()) {
            return write(src);
        }
        int bytesWritten = 0;
        try {
            event.begin();
            bytesWritten = write(src);
        } finally {
            event.bytesWritten = bytesWritten > 0 ? bytesWritten : 0;
            event.path = path;
            event.commit();
            event.reset();
        }
        return bytesWritten;
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public int write(ByteBuffer src, long position) throws IOException {
        FileWriteEvent event = FileWriteEvent.EVENT.get();
        if (!event.isEnabled()) {
            return write(src, position);
        }

        int bytesWritten = 0;
        try {
            event.begin();
            bytesWritten = write(src, position);
        } finally {
            event.bytesWritten = bytesWritten > 0 ? bytesWritten : 0;
            event.path = path;
            event.commit();
            event.reset();
        }
        return bytesWritten;
    }

    @SuppressWarnings("deprecation")
    @JIInstrumentationMethod
    public long write(ByteBuffer[] srcs, int offset, int length) throws IOException {
        FileWriteEvent event = FileWriteEvent.EVENT.get();
        if (!event.isEnabled()) {
            return write(srcs, offset, length);
        }
        long bytesWritten = 0;
        try {
            event.begin();
            bytesWritten = write(srcs, offset, length);
        } finally {
            event.bytesWritten = bytesWritten > 0 ? bytesWritten : 0;
            event.path = path;
            event.commit();

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 {

    public static final ThreadLocal<FileWriteEvent> EVENT =
        new ThreadLocal<>() {
            @Override protected FileWriteEvent initialValue() {
                return new FileWriteEvent();
            }
        };

    @Label("Path")
    @Description("Full path of the file")
    public String path;

    @Label("Bytes Written")
    @Description("Number of bytes written to the file")
    @DataAmount
    public long bytesWritten;

Event configuration settings across JFR profiles
Configuration enabled stackTrace threshold
default true true 20 ms
profiling true true 10 ms

Event fields with their types and descriptions
Field Type Description
path string Path Full path of the file
bytesWritten long: bytes Bytes Written Number of bytes written to the file

Examples 3
Example event data values and properties
bytesWritten long: bytes
1
path string
/tmp/jfr_agent15005275580992799933.jar
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
13
lineNumber int
833
method Method
descriptor string
(I)V
hidden boolean
false
modifiers int
2
name string
writeShort
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
403147523
Example event data values and properties
bytesWritten long: bytes
8144
path string
/tmp/jar_cache13473187686794800317.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
481017789610
Example event data values and properties
bytesWritten long: bytes
8192
path string
/tmp/jar_cache858886477500664727.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
484996127200

Java Application Statistics

JavaThreadStatistics

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

Category: Java Application / Statistics

Code Context

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

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

 *
 *  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
default true 1000 ms
profiling true 1000 ms

Event fields with their types and descriptions
Field Type Description
activeCount long Active Threads Number of live active threads including both daemon and non-daemon threads
daemonCount long Daemon Threads Number of live daemon threads
accumulatedCount long Accumulated Threads Number of threads created and also started since JVM start
peakCount long Peak Threads Peak live thread count since JVM start or when peak count was reset

Examples 3
Example event data values and properties
accumulatedCount long
1955
activeCount long
71
daemonCount long
66
peakCount long
297
startTime long: millis
508364263946
Example event data values and properties
accumulatedCount long
303
activeCount long
21
daemonCount long
16
peakCount long
22
startTime long: millis
14706124901
Example event data values and properties
accumulatedCount long
1885
activeCount long
295
daemonCount long
294
peakCount long
295
startTime long: millis
447961924864

ClassLoadingStatistics

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

Category: Java Application / Statistics

Code Context

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

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

  event.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
default true 1000 ms
profiling true 1000 ms

Event fields with their types and descriptions
Field Type Description
loadedClassCount long Loaded Class Count Number of classes loaded since JVM start
unloadedClassCount long Unloaded Class Count Number of classes unloaded since JVM start

Examples 3
Example event data values and properties
loadedClassCount long
143353
startTime long: millis
507359649959
unloadedClassCount long
8348
Example event data values and properties
loadedClassCount long
3927
startTime long: millis
5447550084
unloadedClassCount long
86
Example event data values and properties
loadedClassCount long
132565
startTime long: millis
458021020272
unloadedClassCount long
3111

ClassLoaderStatistics

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

Category: Java Application / Statistics

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

Missing in: graalvm_linux_native

Code Context

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

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

  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_unsafeAnonymousClassCount(cls->_anon_classes_count);
    event.set_unsafeAnonymousChunkSize(cls->_anon_chunk_sz);
    event.set_unsafeAnonymousBlockSize(cls->_anon_block_sz);
    event.commit();
    return true;

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

Event fields with their types and descriptions
Field Type Description
classLoader ClassLoader Class Loader
parentClassLoader ClassLoader Parent Class Loader
classLoaderData ulong: address ClassLoaderData Pointer Pointer to the ClassLoaderData structure in the JVM
classCount long Classes Number of loaded classes
chunkSize ulong: bytes Total Chunk Size Total size of all allocated metaspace chunks (each chunk has several blocks)
blockSize ulong: bytes Total Block Size Total size of all allocated metaspace blocks (each chunk has several blocks)
unsafeAnonymousClassCount long until JDK 15 Unsafe Anonymous Classes Number of loaded classes to support invokedynamic
unsafeAnonymousChunkSize ulong: bytes until JDK 15 Total Unsafe Anonymous Classes Chunk Size Total size of all allocated metaspace chunks for unsafe anonymous classes (each chunk has several blocks)
unsafeAnonymousBlockSize ulong: bytes until JDK 15 Total Unsafe Anonymous Classes Block Size Total size of all allocated metaspace blocks for unsafe anonymous classes (each chunk has several blocks)

Examples 3
Example event data values and properties
blockSize ulong: bytes
0
chunkSize ulong: bytes
0
classCount long
0
classLoader ClassLoader
null
classLoaderData ulong: address
0
parentClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/util/MutableURLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/util
startTime long: millis
454658362563
Example event data values and properties
blockSize ulong: bytes
101904
chunkSize ulong: bytes
106496
classCount long
16
classLoader ClassLoader
name string
platform
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$PlatformClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/loader
classLoaderData ulong: address
140367183990048
parentClassLoader ClassLoader
null
startTime long: millis
23161970906
Example event data values and properties
blockSize ulong: bytes
2760
chunkSize ulong: bytes
6144
classCount long
1
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
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
140167225729024
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
448951343506

ThreadAllocationStatistics

default profiling startTime every chunk 11 17 21 25 27 28

Category: Java Application / Statistics

Code Context

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

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

  GrowableArray<traceid> thread_ids(initial_size);
  JfrTicks time_stamp = JfrTicks::now();
  {
    // Collect allocation statistics while holding threads lock
    MutexLocker ml(Threads_lock);
    for (JavaThreadIteratorWithHandle jtiwh; JavaThread *jt = jtiwh.next(); ) {
      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
default true everyChunk
profiling true everyChunk

Event fields with their types and descriptions
Field Type Description
allocated ulong: bytes Allocated Approximate number of bytes allocated since thread start
thread Thread Thread

Examples 3
Example event data values and properties
allocated ulong: bytes
0
startTime long: millis
447754205507
thread Thread
group ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Signal Dispatcher
javaThreadId long
11
osName string
Signal Dispatcher
osThreadId long
2159
virtual boolean
false
Example event data values and properties
allocated ulong: bytes
813400752
startTime long: millis
15507180065
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
5014
virtual boolean
false
Example event data values and properties
allocated ulong: bytes
0
startTime long: millis
453049846731
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
HighResTimer
javaThreadId long
894
osName string
HighResTimer
osThreadId long
3708
virtual boolean
false

ExceptionStatistics

default profiling 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/internal/instrument/JDKEvents.java:

        SecurityPropertyModificationEvent.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.SecurityPropertyModificationEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class
    };

    // This is a list of the classes with instrumentation code that should be applied.
    private static final Class<?>[] instrumentationClasses = new 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);
                }
                initializationTriggered = true;
                RequestEngine.addTrustedJDKHook(ExceptionStatisticsEvent.class, emitExceptionStatistics);
            }
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not initialize JDK events. " + e.getMessage());
        }
    }

    public static void addInstrumentation() {
        try {
            List<Class<?>> list = new ArrayList<>();
            for (int i = 0; i < instrumentationClasses.length; i++) {
                JIInstrumentationTarget tgt = instrumentationClasses[i].getAnnotation(JIInstrumentationTarget.class);

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

    @SuppressWarnings("deprecation")
    public static byte[] retransformCallback(Class<?> klass, byte[] oldBytes) throws Throwable {
        if (java.lang.Throwable.class == klass) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.TRACE, "Instrumenting java.lang.Throwable");
            return ConstructorTracerWriter.generateBytes(java.lang.Throwable.class, oldBytes);
        }

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;
}

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

Event fields with their types and descriptions
Field Type Description
throwables long Exceptions Created

Examples 3
Example event data values and properties
startTime long: millis
494788928948
throwables long
2371485
Example event data values and properties
startTime long: millis
490856690011
throwables long
2360260
Example event data values and properties
startTime long: millis
16796560464
throwables long
1073

Java Development Kit

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

public final class JDKEvents {

    private static final Class<?>[] mirrorEventClasses = {
        SecurityPropertyModificationEvent.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,

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/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(x -> x.hashCode())
                    .toArray();
            int anchorCertId =
                    anchor.getTrustedCert().hashCode();
            if (xve.shouldCommit()) {
                xve.certificateId = anchorCertId;
                int certificatePos = 1; //anchor cert
                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;
}

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

Event fields with their types and descriptions
Field Type Description
certificateId 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
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$ValidatorParams;)Ljava/security/cert/PKIXCertPathValidatorResult;
hidden boolean
false
modifiers int
10
name string
validate
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
sun/security/provider/certpath/PKIXCertPathValidator
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
sun/security/provider/certpath
type FrameType
Interpreted
…
truncated boolean
false
startTime long: millis
802369731
validationCounter long
1
Example event data values and properties
certificateId long: certificateId
683561703
certificatePosition int
1
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
472
lineNumber int
242
method Method
descriptor string
(Ljava/security/cert/TrustAnchor;Lsun/security/provider/certpath/PKIX$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
1067306549
validationCounter long
1
Example event data values and properties
certificateId long: certificateId
1917811103
certificatePosition int
3
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
1064399000
validationCounter long
1

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

public final class JDKEvents {

    private static final Class<?>[] mirrorEventClasses = {
        SecurityPropertyModificationEvent.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,

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/java.base/share/classes/sun/security/provider/X509Factory.java:

                length = (highByte << 24 ) | (nextByte << 16) |
                        (midByte << 8) | lowByte;
            } else { // ignore longer length forms
                throw new IOException("Invalid BER/DER data (too huge?)");
            }
            if (readFully(is, bout, length) != length) {
                throw new IOException("Incomplete BER/DER data");
            }
        }
        return tag;
    }

    private void commitEvent(X509CertImpl info) {
        X509CertificateEvent xce = new X509CertificateEvent();
        if (xce.shouldCommit() || EventHelper.isLoggingSecurity()) {
            PublicKey pKey = info.getPublicKey();
            String algId = info.getSigAlgName();
            String serNum = info.getSerialNumber().toString(16);
            String subject = info.getSubjectDN().getName();
            String issuer = info.getIssuerDN().getName();
            String keyType = pKey.getAlgorithm();
            int length = KeyUtil.getKeySize(pKey);
            int hashCode = info.hashCode();
            long beginDate = info.getNotBefore().getTime();
            long endDate = info.getNotAfter().getTime();

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 {
    public String algorithm;
    public String serialNumber;
    public String subject;
    public String issuer;
    public String keyType;
    public int keyLength;
    public long certificateId;
    public long validFrom;
    public long validUntil;
}

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

Event fields with their types and descriptions
Field Type Description
algorithm string Signature Algorithm
serialNumber string Serial Number
subject string Subject
issuer string Issuer
keyType string Key Type
keyLength int Key Length
certificateId long: certificateId Certificate Id
validFrom long: epochmillis Valid From
validUntil long: epochmillis Valid Until

Examples 3
Example event data values and properties
algorithm string
SHA384withECDSA
certificateId long: certificateId
1146488932
issuer string
CN=COMODO ECC Certification Authority, O=COMODO CA Limited, L=Salford, ST=Greater Manchester, C=GB
keyLength int
384
keyType string
EC
serialNumber string
1f:47:af:aa:62:00:70:50:54:4c:01:9e:9b:63:99:2a
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
561249892
subject string
CN=COMODO ECC Certification Authority, O=COMODO CA Limited, L=Salford, ST=Greater Manchester, C=GB
validFrom long: epochmillis
1204761600000
validUntil long: epochmillis
2147471999000
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
679937167
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
SHA1withRSA
certificateId long: certificateId
2034155325
issuer string
CN=SecureTrust CA, O=SecureTrust Corporation, C=US
keyLength int
2048
keyType string
RSA
serialNumber string
0c:f0:8e:5c:08:16:a5:ad:42:7f:f0:eb:27:18:59:d0
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
776898473
subject string
CN=SecureTrust CA, O=SecureTrust Corporation, C=US
validFrom long: epochmillis
1162927878000
validUntil long: epochmillis
1893440455000

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

public final class JDKEvents {

    private static final Class<?>[] mirrorEventClasses = {
        SecurityPropertyModificationEvent.class,
        TLSHandshakeEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

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

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/java.base/share/classes/sun/security/ssl/Finished.java:

            //
            // produce
            if (SSLLogger.isOn && SSLLogger.isOn("ssl,handshake")) {
                SSLLogger.fine(
                "Sending new session ticket");
            }
            NewSessionTicket.kickstartProducer.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;
}

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

Event fields with their types and descriptions
Field Type Description
peerHost string Peer Host
peerPort int Peer Port
protocolVersion string Protocol Version
cipherSuite string Cipher Suite
certificateId long: certificateId Certificate Id Peer Certificate Id

Examples 3
Example event data values and properties
certificateId long: certificateId
998794918
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
832755528
Example event data values and properties
certificateId long: certificateId
998794918
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
1104300297
Example event data values and properties
certificateId long: certificateId
998794918
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
1108105596

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

public final class JDKEvents {

    private static final Class<?>[] mirrorEventClasses = {
        SecurityPropertyModificationEvent.class,
        TLSHandshakeEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

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

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/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;
}

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

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

Examples 3
Example event data values and properties
key string
jdk.disabled.namedCurves
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
891669707
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
1175633602
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
1229926713
value string
secp112r1

Operating System

OSInformation

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

Category: Operating System

Code Context

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

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

  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
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
osVersion string OS Version

Examples 3
Example event data values and properties
osVersion string
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=24.04 DISTRIB_CODENAME=noble DISTRIB_DESCRIPTION="Ubuntu 24.04.4 LTS" uname: Linux 6.17.0-1022-azure #22-Ubuntu SMP Mon Jul 27 17:24:03 UTC 2026 x86_64 libc: glibc 2.39 NPTL 2.39
startTime long: millis
459805727060
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
494566571917
Example event data values and properties
osVersion string
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=24.04 DISTRIB_CODENAME=noble DISTRIB_DESCRIPTION="Ubuntu 24.04.4 LTS" uname: Linux 6.17.0-1022-azure #22-Ubuntu SMP Mon Jul 27 17:24:03 UTC 2026 x86_64 libc: glibc 2.39 NPTL 2.39
startTime long: millis
15623060465

VirtualizationInformation

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

Category: Operating System

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

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized 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
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
name string Name

Examples 3
Example event data values and properties
name string
Hyper-V virtualization
startTime long: millis
364513279
Example event data values and properties
name string
Hyper-V virtualization
startTime long: millis
455586797014
Example event data values and properties
name string
Hyper-V virtualization
startTime long: millis
473917255841

InitialEnvironmentVariable

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

Category: Operating System

Code Context

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

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

  } else if (vrt == PowerFullPartitionMode) {
    return "Power full partition";
  }

  return "No virtualization detected";
}

int JfrOSInterface::generate_initial_environment_variable_events() {
  if (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 = 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
default true beginChunk
profiling true beginChunk

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

Examples 3
Example event data values and properties
key string
PLATFORM
startTime long: millis
364524139
value string
linux
Example event data values and properties
key string
GRADLE_HOME
startTime long: millis
447754187781
value string
/usr/share/gradle-9.7.1
Example event data values and properties
key string
DOTNET_NOLOGO
startTime long: millis
453049821122
value string
1

SystemProcess

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

Category: Operating System

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

Missing in: graalvm_linux_G1GC, graalvm_linux_native

Code Context

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

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

    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
default true endChunk
profiling true endChunk

Event fields with their types and descriptions
Field Type Description
pid string Process Identifier
commandLine string Command Line

Examples 3
Example event data values and properties
commandLine string
kworker/2:1H-kblockd
pid string
107
startTime long: millis
7826905875
Example event data values and properties
commandLine string
/usr/lib/systemd/systemd --user
pid string
1052
startTime long: millis
19479268756
Example event data values and properties
commandLine string
jbd2/sda16-8
pid string
426
startTime long: millis
20528575745

CPUInformation

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

Category: Operating System / Processor

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

Missing in: graalvm_linux_native

Code Context

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

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

TRACE_REQUEST_FUNC(CPUInformation) {
  CPUInformation cpu_info;
  int ret_val = JfrOSInterface::cpu_information(cpu_info);
  if (ret_val == OS_ERR) {
    log_debug(jfr, system)( "Unable to generate requestable event CPUInformation");
    return;
  }
  if (ret_val == FUNCTIONALITY_NOT_IMPLEMENTED) {
     return;
  }
  if (ret_val == OS_OK) {
    EventCPUInformation event;
    event.set_cpu(cpu_info.cpu_name());
    event.set_description(cpu_info.cpu_description());
    event.set_sockets(cpu_info.number_of_sockets());
    event.set_cores(cpu_info.number_of_cores());
    event.set_hwThreads(cpu_info.number_of_hardware_threads());
    event.commit();
  }
}

TRACE_REQUEST_FUNC(CPULoad) {
  double u = 0; // user time

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

Event fields with their types and descriptions
Field Type Description
cpu string Type
description string Description
sockets uint Sockets
cores uint Cores
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
23227651500
Example event data values and properties
cores uint
16
cpu string
AMD Unknown x86 (HT) SSE SSE2 SSE3 SSSE3 SSE4.1 SSE4.2 SSE4A AMD64
description string
Brand: AMD EPYC 7763 64-Core Processor , Vendor: AuthenticAMD Family: Unknown x86 (0x19), Model: <unknown> (0x1), Stepping: 0x1 Ext. family: 0xa, Ext. model: 0x0, Type: 0x0, Signature: 0x00a00f11 Features: ebx: 0x02100800, ecx: 0xfeda3203, edx: 0x178bfbff Ext. features: eax: 0x00a00f1…
hwThreads uint
4
sockets uint
1
startTime long: millis
489606792456
Example event data values and properties
cores uint
16
cpu string
AMD Unknown x86 (HT) SSE SSE2 SSE3 SSSE3 SSE4.1 SSE4.2 SSE4A AMD64
description string
Brand: AMD EPYC 9V74 80-Core Processor , Vendor: AuthenticAMD Family: Unknown x86 (0x19), Model: <unknown> (0x11), Stepping: 0x1 Ext. family: 0xa, Ext. model: 0x1, Type: 0x0, Signature: 0x00a10f11 Features: ebx: 0x02100800, ecx: 0xfeda3203, edx: 0x178bfbff Ext. features: eax: 0x00a10f…
hwThreads uint
4
sockets uint
1
startTime long: millis
484653227903

CPUTimeStampCounter

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

Category: Operating System / Processor

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

Missing in: graalvm_linux_native

Code Context

The event is likely defined and utilized 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
default true beginChunk
profiling true beginChunk

Event fields with their types and descriptions
Field Type Description
fastTimeEnabled boolean Fast Time
fastTimeAutoEnabled boolean Trusted Platform
osFrequency long: hertz OS Frequency
fastTimeFrequency long: hertz Fast Time Frequency

Examples 3
Example event data values and properties
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
364567681
Example event data values and properties
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
462448413223
Example event data values and properties
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
467163461684

CPULoad

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

Category: Operating System / Processor

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

Missing in: graalvm_linux_native

OS CPU Load

Code Context

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

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

TRACE_REQUEST_FUNC(CPULoad) {
  double u = 0; // user time
  double s = 0; // kernel time
  double t = 0; // total time
  int ret_val = JfrOSInterface::cpu_loads_process(&u, &s, &t);
  if (ret_val == OS_ERR) {
    log_debug(jfr, system)( "Unable to generate requestable event CPULoad");
    return;
  }
  if (ret_val == OS_OK) {
    EventCPULoad event;
    event.set_jvmUser((float)u);
    event.set_jvmSystem((float)s);
    event.set_machineTotal((float)t);
    event.commit();
  }
}

TRACE_REQUEST_FUNC(ThreadCPULoad) {
  JfrThreadCPULoadEvent::send_events();
}

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

Event fields with their types and descriptions
Field Type Description
jvmUser float: percentage JVM User
jvmSystem float: percentage JVM System
machineTotal float: percentage Machine Total

Examples 3
Example event data values and properties
jvmSystem float: percentage
0.019323671
jvmUser float: percentage
0.34299517
machineTotal float: percentage
0.36231884
startTime long: millis
24941188580
Example event data values and properties
jvmSystem float: percentage
0.008990111
jvmUser float: percentage
0.46658677
machineTotal float: percentage
0.47557688
startTime long: millis
471028588950
Example event data values and properties
jvmSystem float: percentage
0.0
jvmUser float: percentage
0.265
machineTotal float: percentage
0.265
startTime long: millis
484857097105

ThreadCPULoad

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

Category: Operating System / Processor

Code Context

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

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

int JfrThreadCPULoadEvent::get_processor_count() {
  int cur_processor_count = os::active_processor_count();
  int last_processor_count = _last_active_processor_count;
  _last_active_processor_count = cur_processor_count;

  // If the number of processors decreases, we don't know at what point during
  // the sample interval this happened, so use the largest number to try
  // to avoid percentages above 100%
  return MAX2(cur_processor_count, last_processor_count);
}

// Returns false if the thread has not been scheduled since the last call to updateEvent
// (i.e. the delta for both system and user time is 0 milliseconds)
bool JfrThreadCPULoadEvent::update_event(EventThreadCPULoad& event, JavaThread* thread, jlong cur_wallclock_time, int processor_count) {
  JfrThreadLocal* const tl = thread->jfr_thread_local();

  jlong cur_cpu_time = os::thread_cpu_time(thread, true);
  jlong prev_cpu_time = tl->get_cpu_time();

  jlong prev_wallclock_time = tl->get_wallclock_time();
  tl->set_wallclock_time(cur_wallclock_time);

  // Threshold of 1 ms
  if (cur_cpu_time - prev_cpu_time < 1 * NANOSECS_PER_MILLISEC) {
    return false;

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

void JfrThreadCPULoadEvent::send_events() {
  Thread* periodic_thread = Thread::current();
  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();

  JavaThreadIteratorWithHandle jtiwh;
  while (JavaThread* jt = jtiwh.next()) {
    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", jtiwh.length(),
    (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
default true 10 s
profiling true 10 s

Event fields with their types and descriptions
Field Type Description
user float: percentage User Mode CPU Load User mode thread CPU load
system float: percentage System Mode CPU Load System mode thread CPU load

Examples 3
Example event data values and properties
startTime long: millis
554202797
system float: percentage
7.798856E-4
user float: percentage
0.12168565
Example event data values and properties
startTime long: millis
461269819977
system float: percentage
4.7204965E-5
user float: percentage
0.0
Example event data values and properties
startTime long: millis
455798353258
system float: percentage
2.400952E-5
user float: percentage
0.0

ThreadContextSwitchRate

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

Category: Operating System / Processor

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

Missing in: graalvm_linux_native

Code Context

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

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

TRACE_REQUEST_FUNC(ThreadContextSwitchRate) {
  double rate = 0.0;
  int 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
default true 10 s
profiling true 10 s

Event fields with their types and descriptions
Field Type Description
switchRate float: hertz Switch Rate Number of context switches per second

Examples 3
Example event data values and properties
startTime long: millis
499023579954
switchRate float: hertz
3209.185
Example event data values and properties
startTime long: millis
495798945486
switchRate float: hertz
5066.3643
Example event data values and properties
startTime long: millis
10584510779
switchRate float: hertz
9365.798

NetworkUtilization

default profiling startTime every chunk 11 17 21 25 27 28

Category: Operating System / Network

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

Missing in: graalvm_linux_native

Code Context

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

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

  static JfrTicks last_sample_instant;
  const JfrTicks cur_time = JfrTicks::now();
  const JfrTickspan interval = last_sample_instant == 0 ? cur_time - cur_time : cur_time - last_sample_instant;
  last_sample_instant = cur_time;
  for (NetworkInterface *cur = network_interfaces; cur != NULL; cur = cur->next()) {
    InterfaceEntry& entry = get_entry(cur);
    if (interval.value() > 0) {
      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) {
        entry.in_use = true;
        EventNetworkUtilization event(UNTIMED);
        event.set_starttime(cur_time);
        event.set_endtime(cur_time);
        event.set_networkInterface(entry.id);
        event.set_readRate(8 * read_rate);
        event.set_writeRate(8 * write_rate);
        event.commit();
      }
      // update existing entry with new values
      entry.bytes_in = current_bytes_in;
      entry.bytes_out = current_bytes_out;
    }

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

Event fields with their types and descriptions
Field Type Description
networkInterface NetworkInterfaceName Network Interface Network Interface Name
readRate long: bits-per-second Read Rate Number of incoming bits per second
writeRate long: bits-per-second Write Rate Number of outgoing bits per second

Examples 3
Example event data values and properties
networkInterface NetworkInterfaceName
eth0
readRate long: bits-per-second
12800
startTime long: millis
15726471693
writeRate long: bits-per-second
11712
Example event data values and properties
networkInterface NetworkInterfaceName
eth0
readRate long: bits-per-second
4336
startTime long: millis
474301325085
writeRate long: bits-per-second
5944
Example event data values and properties
networkInterface NetworkInterfaceName
enP24070s1
readRate long: bits-per-second
4192
startTime long: millis
484104974762
writeRate long: bits-per-second
5568

PhysicalMemory

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

Category: Operating System / Memory

OS Physical Memory

Code Context

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

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

 *  PhysicalMemory event represents:
 *
 *  @totalSize == The amount of physical memory (hw) installed and reported by the OS, in bytes.
 *  @usedSize  == The amount of physical memory currently in use in the system (reserved/committed), in bytes.
 *
 *  Both fields are systemwide, i.e. represents the entire OS/HW environment.
 *  These fields do not include virtual memory.
 *
 *  If running inside a guest OS on top of a hypervisor in a virtualized environment,
 *  the total memory reported is the amount of memory configured for the guest OS by the hypervisor.
 */
TRACE_REQUEST_FUNC(PhysicalMemory) {
  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
default true everyChunk
profiling true everyChunk

Event fields with their types and descriptions
Field Type Description
totalSize ulong: bytes Total Size Total amount of physical memory available to OS
usedSize ulong: bytes Used Size Total amount of physical memory in use

Examples 3
Example event data values and properties
startTime long: millis
454119543708
totalSize ulong: bytes
16766414848
usedSize ulong: bytes
7026561024
Example event data values and properties
startTime long: millis
25441041160
totalSize ulong: bytes
16766414848
usedSize ulong: bytes
1191432192
Example event data values and properties
startTime long: millis
467163508351
totalSize ulong: bytes
16766414848
usedSize ulong: bytes
3619721216

Types

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
(Ljava/lang/Class;)Ljava/lang/Object;
name string
allocateInstance
type string
jdk/internal/misc/Unsafe
Example event data values and properties
descriptor string
()V
name string
<init>
type string
java/lang/Object
Example event data values and properties
descriptor string
(Ljdk/jfr/internal/LogTag;Ljdk/jfr/internal/LogLevel;)Z
name string
shouldLog
type string
jdk/jfr/internal/Logger

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

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 'non-profiled nmethods'

CompilerPhaseType

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

Missing in: graalvm_linux_native

Compiler Phase Type

Event fields with their types and descriptions
Field Type Description
phase string Phase

Examples 3
After Macro Expansion Step
After CountedLoop
After Iter GVN

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

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
JIT compiled
Native

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: bytes Region Refills Total memory wasted at the end of regions due to refill
directAllocated ulong: bytes Allocated (direct) Total memory allocated using direct allocation outside of PLABs
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
1171
regionEndWaste ulong: bytes
0
regionsRefilled uint: bytes
1
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0
Example event data values and properties
allocated ulong: bytes
2097152
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
27
regionEndWaste ulong: bytes
0
regionsRefilled uint: bytes
1
undoWaste ulong: bytes
0
used ulong: bytes
2043680
wasted ulong: bytes
53472
Example event data values and properties
allocated ulong: bytes
319424
directAllocated ulong: bytes
1090312
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1140
regionEndWaste ulong: bytes
0
regionsRefilled uint: bytes
1
undoWaste ulong: bytes
0
used ulong: bytes
304656
wasted ulong: bytes
3104

G1HeapRegionType

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

G1 Heap Region Type

Event fields with their types and descriptions
Field Type Description
type string Type

Examples 3

G1YCType

Appearing in: graalvm_linux_G1GC, linux_G1GC

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

G1 YC Type

Event fields with their types and descriptions
Field Type Description
type string Type

Examples 3
Normal
Concurrent Start
Concurrent Start

GCCause

GC Cause

Event fields with their types and descriptions
Field Type Description
cause string Cause

Examples 3
System.gc()
G1 Humongous Allocation
System.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 Wait

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
957612032
reserved ulong: bytes
1879048192
used ulong: bytes
954064904
Example event data values and properties
committed ulong: bytes
179175424
reserved ulong: bytes
1073741824
used ulong: bytes
177476696
Example event data values and properties
committed ulong: bytes
778436608
reserved ulong: bytes
805306368
used ulong: bytes
776588208

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
32398901248
size ulong: bytes
2231369728
start ulong: address
30167531520
used ulong: bytes
232519720
Example event data values and properties
end ulong: address
34070331392
size ulong: bytes
6291456
start ulong: address
34064039936
used ulong: bytes
5062704
Example event data values and properties
end ulong: address
33885782016
size ulong: bytes
922746880
start ulong: address
32963035136
used ulong: bytes
922746880

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
30168595528
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[I
package Package
null
Example event data values and properties
address ulong: address
30366496984
description string
Size: 1
referrer Reference
null
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
0
name string
org/apache/hadoop/metrics2/lib/Interns$CacheWith2Keys$2
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/hadoop/metrics2/lib
Example event data values and properties
address ulong: address
31562137600
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1040
name string
[Ljava/util/concurrent/ConcurrentHashMap$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

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
Weak reference
Phantom reference
Final reference

ShenandoahHeapRegionState

Appearing in: linux_ShenandoahGC

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

Shenandoah Heap Region State

Event fields with their types and descriptions
Field Type Description
state string State

Examples 3
Empty Uncommitted
Humongous Continuation
Empty Committed

StackFrame

Event fields with their types and descriptions
Field Type Description
method Method Java Method
lineNumber int Line Number
bytecodeIndex int Bytecode Index
type FrameType Frame Type

Examples 3
Example event data values and properties
bytecodeIndex int
12
lineNumber int
500
method Method
descriptor string
(Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
false
modifiers int
8
name string
allocateInstance
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/invoke/DirectMethodHandle
package Package
exported boolean
true
module Module
classLoader ClassLoader
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
type FrameType
Inlined
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
26
lineNumber int
71
method Method
descriptor string
(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
false
modifiers int
1
name string
apply
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1537
name string
breeze/linalg/operators/BinaryRegistry
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg/operators
type FrameType
JIT compiled

StackTrace

Stacktrace

Event fields with their types and descriptions
Field Type Description
truncated boolean Truncated
frames array StackFrame struct Stack Frames

Examples 3
Example event data values and properties
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
type FrameType
Native
…
truncated boolean
false
Example event data values and properties
frames StackFrame
bytecodeIndex int
12
lineNumber int
500
method Method
descriptor string
(Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
false
modifiers int
8
name string
allocateInstance
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/invoke/DirectMethodHandle
package Package
exported boolean
true
module Module
classLoader ClassLoader
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
type FrameType
Inlined
…
truncated boolean
false
Example event data values and properties
frames StackFrame
bytecodeIndex int
26
lineNumber int
71
method Method
descriptor string
(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
false
modifiers int
1
name string
apply
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1537
name string
breeze/linalg/operators/BinaryRegistry
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg/operators
type FrameType
JIT compiled
…
truncated boolean
false

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
Example event data values and properties
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
null
Example event data values and properties
name string
system
parent ThreadGroup
null

ThreadState

Java Thread State

Event fields with their types and descriptions
Field Type Description
name string Name

Examples 3
STATE_RUNNABLE
STATE_RUNNABLE
STATE_RUNNABLE

VMOperationType

VM Operation Type

Event fields with their types and descriptions
Field Type Description
type string Type

Examples 3
HeapIterateOperation
ClassLoaderStatsOperation
JFRSafepointWrite

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
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
30196891648
committedSize ulong: bytes
29360128
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
Example event data values and properties
committedEnd ulong: address
33571209216
committedSize ulong: bytes
3403677696
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520

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 OopStorageSet
Young Generation (Collect Roots)

XML Content Types

address

Annotation: jdk.jfr.MemoryAddress

Examples 3
30414995456
94895174441632
30362878480

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
1.434936509750703E8
2.958066287106632E8
0.0

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
2034155325
998794918
1917811103

epochmillis

Annotation: jdk.jfr.Timestamp(MILLISECONDS_SINCE_EPOCH)

Examples 3
1788871449128
-9223372036854775808
1788871449508

hertz

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

Missing in: graalvm_linux_native

Annotation: jdk.jfr.Frequency

Examples 3

millis

Annotation: jdk.jfr.Timespan(MILLISECONDS)

Examples 3
452948726203
453332151620
453405618156

nanos

Annotation: jdk.jfr.Timespan(NANOSECONDS)

Examples 3
-9223372036854775808
59999999970
4963513

percentage

Annotation: jdk.jfr.Percentage

Examples 3

tickspan

Annotation: jdk.jfr.Timespan(TICKS)

Examples 3

tickstamp

Annotation: jdk.jfr.Timestamp(TICKS)

XML Types

Class

Property Value
Parameter Type const Klass*
Field Type const Klass*
Java Type java.lang.Class
Examples 3
null
null
Example event data values and properties
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionObject
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent/locks

ClassLoader

Property Value
Parameter Type const ClassLoaderData*
Field Type const ClassLoaderData*
Examples 3
Example event data values and properties
name string
bootstrap
type Class
null
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
(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
false
modifiers int
1
name string
apply
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
hidden boolean
false
modifiers int
1537
name string
breeze/linalg/operators/BinaryRegistry
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg/operators
Example event data values and properties
descriptor string
(Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
false
modifiers int
8
name string
allocateInstance
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/invoke/DirectMethodHandle
package Package
exported boolean
true
module Module
classLoader ClassLoader
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
Example event data values and properties
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc

Module

Property Value
Parameter Type const ModuleEntry*
Field Type const ModuleEntry*
Examples 3
Example event data values and properties
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
Example event data values and properties
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
Example event data values and properties
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1

Package

Property Value
Parameter Type const PackageEntry*
Field Type const PackageEntry*
Examples 3
Example event data values and properties
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/util/concurrent/locks
Example event data values and properties
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
jdk/internal/misc
Example event data values and properties
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.4.1
name string
java/net

Thread

Property Value
Parameter Type u8
Field Type u8
Java Type java.lang.Thread
Examples 3
Example event data values and properties
group ThreadGroup
name string
finagle/netty4
parent ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
finagle/netty4-2-1
javaThreadId long
895
osName string
finagle/netty4-2-1
osThreadId long
3710
virtual boolean
false
Example event data values and properties
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 3.0 in stage 47.0 (TID 185)
javaThreadId long
1729
osName string
Executor task launch worker for task 3.0 in stage 47.0 (TID 185)
osThreadId long
4645
virtual boolean
false
null

Ticks

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
428309336588
244554643603
734761909

Tickspan

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
2.2248921
4.9328766
4.9501452

int

Property Value
Parameter Type s4
Field Type s4
Java Type int
Examples 3

long

Property Value
Parameter Type s8
Field Type s8
Java Type long
Examples 3

short

Property Value
Parameter Type s2
Field Type s2
Java Type short

string

Property Value
Parameter Type const char*
Field Type const char*
Java Type java.lang.String
Examples 3
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionObject
bootstrap
java/util/concurrent/locks

ubyte

unsigned

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

Missing in: graalvm_linux_native

Property Value
Parameter Type u1
Field Type u1
Java Type byte
Examples 3

uint

unsigned

Property Value
Parameter Type unsigned
Field Type unsigned
Java Type int
Examples 3

ulong

unsigned

Property Value
Parameter Type u8
Field Type u8
Java Type long
Examples 3

ushort

unsigned

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

Missing in: graalvm_linux_native

Property Value
Parameter Type u2
Field Type u2
Java Type short
Examples 3