Introduction

The following are the events for OpenJDK 18 (jdk-18.0.3+0, permalink, 03-June-2026). The events are collected from the event configuration and the 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.

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 26 27

Category: Flight Recorder

Who requested the recording and why

Code Context

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

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

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

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

Configuration enabled
default true
profiling true

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

DataLoss

default profiling startTime 11 17 21 25 26 27

Category: Flight Recorder

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

Code Context

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

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

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

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

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

Configuration enabled
default true
profiling true

Field Type Description
amount ulong: bytes Amount Amount lost data
total ulong: bytes Total Total lost amount for thread

Flush

experimental startTime duration 14 17 21 25 26 27

Category: Flight Recorder

Code Context

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

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

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

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

class StackTraceRepository : public StackObj {
 private:

Configuration enabled threshold
default false 0 ns
profiling false 0 ns

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

Examples 3
elements ulong
5916
flushId ulong
8
size ulong: bytes
1272453
startTime long: millis
8432446046
elements ulong
5717
flushId ulong
74
size ulong: bytes
747136
startTime long: millis
76858765993
elements ulong
128
flushId ulong
12
size ulong: bytes
669671
startTime long: millis
12655629139

ActiveRecording

default profiling startTime duration stackTrace 11 17 21 25 26 27

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

Category: Flight Recorder

Code Context

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

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

@Name(Type.EVENT_NAME_PREFIX + "ActiveRecording")
@Label("Flight Recording")
@Category("Flight Recorder")
@StackTrace(false)
public final class ActiveRecordingEvent extends AbstractJDKEvent {

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

    @Label("Id")
    public long id;

    @Label("Name")
    public String name;

    @Label("Destination")
    public String destination;

    @Label("Max Age")

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

        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ExceptionThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ErrorThrownEvent.class,
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,

        DirectBufferStatisticsEvent.class
    };

    // This is a list of the classes with instrumentation code that should be applied.

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

    private RepositoryChunk currentChunk;
    private boolean inShutdown;

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

    }


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

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

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

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

Configuration enabled
default true
profiling true

Field Type Description
id long Id
name string Name
destination string Destination
maxAge long: millis Max Age
flushInterval long: millis 14+ Flush Interval
maxSize long: bytes Max Size
recordingStart long: epochmillis Start Time
recordingDuration long: millis Recording Duration

Examples 3
destination string
/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseParallelGC.jfr
flushInterval long: millis
1000
id long
1
maxAge long: millis
9223372036854775807
maxSize long: bytes
262144000
name string
1
recordingDuration long: millis
9223372036854775807
recordingStart long: epochmillis
1780495561697
startTime long: millis
79133745260
destination string
/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseG1GC.jfr
flushInterval long: millis
1000
id long
1
maxAge long: millis
9223372036854775807
maxSize long: bytes
262144000
name string
1
recordingDuration long: millis
9223372036854775807
recordingStart long: epochmillis
1780495574399
startTime long: millis
99244064933
destination string
/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseG1GC_events.jfr
flushInterval long: millis
1000
id long
1
maxAge long: millis
9223372036854775807
maxSize long: bytes
0
name string
1
recordingDuration long: millis
27000
recordingStart long: epochmillis
1780495704241
startTime long: millis
370445781

ActiveSetting

default profiling startTime duration stackTrace 11 17 21 25 26 27

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

Category: Flight Recorder

Code Context

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

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

package jdk.jfr.events;

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

@Name(Type.EVENT_NAME_PREFIX + "ActiveSetting")
@Label("Recording Setting")
@Category("Flight Recorder")
@StackTrace(false)
public final class ActiveSettingEvent extends AbstractJDKEvent {

    public static final ThreadLocal<ActiveSettingEvent> EVENT = new ThreadLocal<ActiveSettingEvent>() {
        @Override
        protected ActiveSettingEvent initialValue() {
            return new ActiveSettingEvent();
        }
    };

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

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

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

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

        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ExceptionThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ErrorThrownEvent.class,
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,

        DirectBufferStatisticsEvent.class
    };

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

    private boolean inShutdown;

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

    }


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

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

    void disable() {
        for (NamedControl nc : namedControls) {
            if (nc.control.isType(EnabledSetting.class)) {
                nc.control.setValue("false");
                return;
            }
        }
    }

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

Configuration enabled
default true
profiling true

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

Examples 3
id long
37
name string
enabled
startTime long: millis
356902428
value string
true
id long
18
name string
threshold
startTime long: millis
381521681
value string
0 ms
id long
17
name string
enabled
startTime long: millis
370445781
value string
true

JVM

JVMInformation

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

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) {

Configuration enabled period
default true beginChunk
profiling true beginChunk

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

Examples 3
javaArguments string
/home/runner/work/jfrevents/jfrevents/.cache/renaissance.jar -t 5 -r 1 all
jvmArguments string
-XX:StartFlightRecording=filename=/home/runner/work/jfrevents/jfrevents/jfr/sample_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
1780495574039
jvmVersion string
OpenJDK 64-Bit Server VM (25.0.3+9-LTS) for linux-amd64 JRE (25.0.3+9-LTS), built on 2026-04-20T14:40:29Z with gcc 14.2.0
pid long
2776
startTime long: millis
384232489
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
1780495561360
jvmVersion string
OpenJDK 64-Bit Server VM (25.0.3+9-LTS) for linux-amd64 JRE (25.0.3+9-LTS), built on 2026-04-20T14:40:29Z with gcc 14.2.0
pid long
2792
startTime long: millis
79134335518
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
1780495703889
jvmVersion string
OpenJDK 64-Bit Server VM (25.0.3+9-LTS) for linux-amd64 JRE (25.0.3+9-LTS), built on 2026-04-20T14:40:29Z with gcc 14.2.0
pid long
3276
startTime long: millis
8304151539

InitialSystemProperty

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

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;

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
key string Key
value string Value

Examples 3
key string
sun.boot.library.path
startTime long: millis
17207059779
value string
/opt/hostedtoolcache/Java_SapMachine_jdk/25.0.3/x64/lib
key string
java.vm.specification.vendor
startTime long: millis
9232254820
value string
Oracle Corporation
key string
sun.boot.library.path
startTime long: millis
16515908717
value string
/opt/hostedtoolcache/Java_SapMachine_jdk/25.0.3/x64/lib

JVM: Class Loading

ClassLoad

startTime duration eventThread stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / Class Loading

Code Context

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

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

//

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

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

 public:

  // Returns a class with a given class name and class loader.  Loads the

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

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

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

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

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

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

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

  EventClassLoad class_load_start_event;

  HandleMark hm(THREAD);

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

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

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

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

  EventClassLoad class_load_start_event;
  ClassLoaderData* loader_data;

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

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

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

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

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

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

  EventClassLoad class_load_start_event;
  {
    MutexLocker mu_r(THREAD, Compile_lock);

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

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

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

Examples 3
definingClassLoader ClassLoader
name string
bootstrap
type Class
null
initiatingClassLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
loadedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/String
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Z)[Ljava/lang/reflect/Method;
hidden boolean
false
modifiers int
258
name string
getDeclaredMethods0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Class
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
408347754
definingClassLoader ClassLoader
name string
bootstrap
type Class
null
initiatingClassLoader ClassLoader
name string
bootstrap
type Class
null
loadedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
8
name string
java/util/Collections$SynchronizedSet
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
2415
method Method
descriptor string
(Ljava/util/Set;Ljava/lang/Object;)Ljava/util/Set;
hidden boolean
false
modifiers int
8
name string
synchronizedSet
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/util/Collections
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
375657926
definingClassLoader ClassLoader
name string
bootstrap
type Class
null
initiatingClassLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
loadedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/locks/ReentrantLock
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util/concurrent/locks
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
14
lineNumber int
415
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
<clinit>
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
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
25.0.3
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
395738268

ClassDefine

startTime eventThread stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / Class Loading

Code Context

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

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

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

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

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

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

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

Configuration enabled stackTrace
default false true
profiling false true

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

Examples 3
definedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
8
name string
jdk/internal/math/FloatingDecimal$BinaryToASCIIBuffer
package Package
exported boolean
false
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/math
definingClassLoader ClassLoader
name string
bootstrap
type Class
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
40
lineNumber int
251
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
<clinit>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
jdk/internal/math/FloatingDecimal
package Package
exported boolean
false
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/math
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
398835419
definedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
16409
name string
java/lang/System$Logger$Level
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
definingClassLoader ClassLoader
name string
bootstrap
type Class
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
9
lineNumber int
58
method Method
descriptor string
()Ljava/lang/System$Logger$Level;
hidden boolean
false
modifiers int
8
name string
getDefaultLevel
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
jdk/internal/logger/SimpleConsoleLogger
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/logger
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
410305194
definedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
4104
name string
java/time/LocalDate$1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/time
definingClassLoader ClassLoader
name string
bootstrap
type Class
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
686
method Method
descriptor string
(Ljava/time/temporal/TemporalField;)I
hidden boolean
false
modifiers int
2
name string
get0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/time/LocalDate
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/time
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
387744069

ClassRedefinition

default profiling startTime 15 17 21 25 26 27

Category: Java Virtual Machine / Class Loading

Code Context

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

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

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

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

  increment_class_counter(the_class);

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

  {
    ResourceMark rm(current);
    // increment the classRedefinedCount field in the_class and in any
    // direct and indirect subclasses of the_class
    log_info(redefine, class, load)

Configuration enabled
default true
profiling true

Field Type Description
redefinedClass Class Redefined Class
classModificationCount int Class Modification Count The number of times the class has changed
redefinitionId ulong Class Redefinition Id

Examples 3
classModificationCount int
2
redefinedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/ArrayList
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util
redefinitionId ulong
2
startTime long: millis
1213087022
classModificationCount int
1
redefinedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/ArrayList
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util
redefinitionId ulong
1
startTime long: millis
1444666464
classModificationCount int
1
redefinedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/ArrayList
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util
redefinitionId ulong
1
startTime long: millis
1279014155

RedefineClasses

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

Category: Java Virtual Machine / Class Loading

Code Context

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

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

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


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

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

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

Examples 3
classCount int
1
redefinitionId ulong
2
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/instrument/ClassDefinition;)V
hidden boolean
false
modifiers int
258
name string
redefineClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.3
name string
sun/instrument
type FrameType
Native
truncated boolean
false
startTime long: millis
1285848137
classCount int
1
redefinitionId ulong
2
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/instrument/ClassDefinition;)V
hidden boolean
false
modifiers int
258
name string
redefineClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.3
name string
sun/instrument
type FrameType
Native
truncated boolean
false
startTime long: millis
1451698506
classCount int
1
redefinitionId ulong
2
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/instrument/ClassDefinition;)V
hidden boolean
false
modifiers int
258
name string
redefineClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.3
name string
sun/instrument
type FrameType
Native
truncated boolean
false
startTime long: millis
1210577187

RetransformClasses

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

Category: Java Virtual Machine / Class Loading

Code Context

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

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

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

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

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

Examples 3
classCount int
1
redefinitionId ulong
1
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/Class;)V
hidden boolean
false
modifiers int
258
name string
retransformClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.3
name string
sun/instrument
type FrameType
Native
truncated boolean
false
startTime long: millis
1274739605
classCount int
1
redefinitionId ulong
1
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/Class;)V
hidden boolean
false
modifiers int
258
name string
retransformClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.3
name string
sun/instrument
type FrameType
Native
truncated boolean
false
startTime long: millis
1200860390
classCount int
1
redefinitionId ulong
1
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J[Ljava/lang/Class;)V
hidden boolean
false
modifiers int
258
name string
retransformClasses0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
sun/instrument/InstrumentationImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.instrument
name string
java.instrument
version string
25.0.3
name string
sun/instrument
type FrameType
Native
truncated boolean
false
startTime long: millis
1439988593

ClassUnload

startTime eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Class Loading

Code Context

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

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

  ClassLoadingService::notify_class_unloaded(ik);

  SystemDictionaryShared::handle_class_unloading(ik);

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

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

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

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

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

Configuration enabled
default false
profiling false

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

Examples 3
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/net
startTime long: millis
5096433930
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
25.0.3
name string
java/net
hidden boolean
true
modifiers int
4112
name string
org.renaissance.jdk.streams.JavaScrabble$$Lambda/0x0000000024297400
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
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
org/renaissance/jdk/streams
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
25.0.3
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
25.0.3
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
startTime long: millis
2447503035
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
25.0.3
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
25.0.3
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/Unloadable366857369101
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
25.0.3
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
25.0.3
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
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
25.0.3
name string
java/net
startTime long: millis
3941784959
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
25.0.3
name string
java/net
hidden boolean
false
modifiers int
1
name string
scala/collection/mutable/ListBuffer
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
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection/mutable

JVM: Code Cache

CodeCacheFull

default profiling startTime eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Code Cache

Code Context

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

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

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

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

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

Configuration enabled
default true
profiling true

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

CodeCacheStatistics

default profiling startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Code Cache

Code Context

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

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

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

Configuration enabled period
default true everyChunk
profiling true everyChunk

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

Examples 3
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'profiled nmethods'
entryCount int
1690
fullCount int
0
methodCount int
1690
reservedTopAddress ulong: address
140142291451904
startAddress ulong: address
140142167719936
startTime long: millis
8156660897
unallocatedCapacity ulong: bytes
120347008
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'profiled nmethods'
entryCount int
3512
fullCount int
0
methodCount int
3512
reservedTopAddress ulong: address
140405156872192
startAddress ulong: address
140405033140224
startTime long: millis
28322611370
unallocatedCapacity ulong: bytes
116760704
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'profiled nmethods'
entryCount int
4493
fullCount int
0
methodCount int
4493
reservedTopAddress ulong: address
140680974303232
startAddress ulong: address
140680850571264
startTime long: millis
127879258202
unallocatedCapacity ulong: bytes
114760576

CodeCacheConfiguration

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

Category: Java Virtual Machine / Code Cache

Code Context

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

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

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

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

Configuration enabled period
default true beginChunk
profiling true beginChunk

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

Examples 3
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
6291456
nonProfiledSize ulong: bytes
123731968
profiledSize ulong: bytes
123731968
reservedSize ulong: bytes
253755392
reservedTopAddress ulong: address
140681104326656
startAddress ulong: address
140680850571264
startTime long: millis
126448944968
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
140405286895616
startAddress ulong: address
140405033140224
startTime long: millis
96796215934
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
140142421475328
startAddress ulong: address
140142167719936
startTime long: millis
8304308062

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:

  sweep_code_cache();

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

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

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

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

  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;

Configuration enabled threshold
default true 100 ms
profiling true 100 ms

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);

Configuration enabled period
default true everyChunk
profiling true everyChunk

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.set_sweepThreshold(NMethodSweeper::sweep_threshold_bytes());
  event.commit();
}

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

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
sweeperEnabled boolean Code Sweeper Enabled
flushingEnabled boolean Code Cache Flushing Enabled
sweepThreshold ulong: bytes 17 until JDK 20 Sweep Threshold

JVM: Compiler

Compilation

default profiling startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Compiler

Code Context

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

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

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

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

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

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

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

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

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

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

  class PhaseEvent : AllStatic {
    friend class CompilerPhaseTypeConstant;
   public:

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

        _compilation_log->log_nmethod(thread, code);
      }
    }
  } 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);
    }
  }
}

static void post_compilation_event(EventCompilation& event, CompileTask* task) {
  assert(task != NULL, "invariant");
  CompilerEvent::CompilationEvent::post(event,
                                        task->compile_id(),
                                        task->compiler()->type(),
                                        task->method(),
                                        task->comp_level(),
                                        task->is_success(),
                                        task->osr_bci() != CompileBroker::standard_entry_bci,
                                        (task->code() == NULL) ? 0 : task->code()->total_size(),
                                        task->num_inlined_bytecodes());
}

int DirectivesStack::_depth = 0;

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

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

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

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

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

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

    bool method_is_old = ci_env.cache_jvmti_state();

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

    // Cache DTrace flags
    ci_env.cache_dtrace_flags();

    ciMethod* target = ci_env.get_method_from_handle(target_handle);

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

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

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

package jdk.vm.ci.hotspot;

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        void setCompileId(int compileId);

        void setCompileLevel(int compileLevel);

        void setSucceeded(boolean succeeded);

Configuration enabled threshold
default true 1000 ms
profiling true 100 ms

Field Type Description
compileId uint Compilation Identifier
compiler CompilerType 14+ Compiler
method Method Method
compileLevel ushort Compilation Level
succeded boolean Succeeded
isOsr boolean On Stack Replacement
codeSize ulong: bytes Compiled Code Size
inlinedBytes ulong: bytes Inlined Code Size

Examples 3
codeSize ulong: bytes
2000
compileId uint
1468
compileLevel ushort
3
compiler CompilerType
c1
inlinedBytes ulong: bytes
0
isOsr boolean
false
method Method
descriptor string
(Ljava/util/regex/Matcher;ILjava/lang/CharSequence;)Z
hidden boolean
false
modifiers int
0
name string
match
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
24
name string
java/util/regex/Pattern$BmpCharPropertyGreedy
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util/regex
startTime long: millis
415178166
succeded boolean
true
codeSize ulong: bytes
3944
compileId uint
1410
compileLevel ushort
3
compiler CompilerType
c1
inlinedBytes ulong: bytes
83
isOsr boolean
false
method Method
descriptor string
(Ljdk/jfr/internal/event/EventConfiguration;J)Z
hidden boolean
false
modifiers int
1
name string
beginEvent
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/jfr/internal/event/EventWriter
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.jfr
name string
jdk.jfr
version string
25.0.3
name string
jdk/jfr/internal/event
startTime long: millis
374409948
succeded boolean
true
codeSize ulong: bytes
1472
compileId uint
1452
compileLevel ushort
3
compiler CompilerType
c1
inlinedBytes ulong: bytes
1
isOsr boolean
false
method Method
descriptor string
(Ljava/lang/invoke/VarHandle;Ljava/lang/Object;I)I
hidden boolean
false
modifiers int
8
name string
get
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
24
name string
java/lang/invoke/VarHandleByteArrayAsInts$ArrayHandle
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang/invoke
startTime long: millis
408856947
succeded boolean
true

CompilerPhase

default profiling startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Compiler

Code Context

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

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

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

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

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

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

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

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

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

  event.set_succeded(success);
  event.set_isOsr(is_osr);
  event.set_codeSize(code_size);
  event.set_inlinedBytes(inlined_bytecodes);
  event.commit();
}

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

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

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

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

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

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

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

  class CompilationEvent : AllStatic {
   public:

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

  class PhaseEvent : AllStatic {
    friend class CompilerPhaseTypeConstant;
   public:

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

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

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

src/hotspot/share/jvmci/jvmciCompilerToVM.cpp:

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

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

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

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

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

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

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

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

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

Configuration enabled threshold
default true 60 s
profiling true 10 s

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

Examples 3
compileId uint
1344
phase CompilerPhaseType
After Iter GVN
phaseLevel ushort
3
startTime long: millis
358815381
compileId uint
1380
phase CompilerPhaseType
Conservative coalescing
phaseLevel ushort
4
startTime long: millis
383246294
compileId uint
1408
phase CompilerPhaseType
Fix up spills
phaseLevel ushort
4
startTime long: millis
373982130

CompilationFailure

profiling startTime eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Compiler

Code Context

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

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

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

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

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

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

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

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

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

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

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

  class PhaseEvent : AllStatic {
    friend class CompilerPhaseTypeConstant;
   public:

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

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

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

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

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

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

Configuration enabled
default false
profiling true

Field Type Description
failureMessage string Failure Message
compileId uint Compilation Identifier

Examples 3
compileId uint
2691
failureMessage string
Jvmti state change invalidated dependencies
startTime long: millis
1468204191
compileId uint
22154
failureMessage string
out of virtual registers in LIR generator
startTime long: millis
58209947669
compileId uint
10514
failureMessage string
retry without subsuming loads
startTime long: millis
29443681490

CompilerInlining

startTime eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Compiler / Optimization

Code Context

The event is likely defined and utilized 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:

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

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

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

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

  CompileTask::print_inlining_ul(callee_method, inline_level(),
                                               caller_bci, inline_msg);
  if (C->print_inlining()) {
    C->print_inlining(callee_method, inline_level(), caller_bci, inline_msg);
    guarantee(callee_method != NULL, "would crash in CompilerEvent::InlineEvent::post");
    if (Verbose) {
      const InlineTree *top = this;
      while (top->caller_tree() != NULL) { top = top->caller_tree(); }
      //tty->print("  bcs: %d+%d  invoked: %d", top->count_inline_bcs(), callee_method->code_size(), callee_method->interpreter_invocation_count());
    }
  }
  EventCompilerInlining event;
  if (event.should_commit()) {
    CompilerEvent::InlineEvent::post(event, C->compile_id(), caller_method->get_Method(), callee_method, success, inline_msg, caller_bci);
  }
}

//------------------------------ok_to_inline-----------------------------------
bool InlineTree::ok_to_inline(ciMethod* callee_method, JVMState* jvms, ciCallProfile& profile,
                              bool& should_delay) {
#ifdef ASSERT
  assert(callee_method != NULL, "caller checks for optimized virtual!");
  // Make sure the incoming jvms has the same information content as me.

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

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

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

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

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

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

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

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

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

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

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

    // there must not be an existing registration for `phase_name`.
    // If `use_strdup` is true, then `phase_name` is strdup'ed before registration.
    // If `sync` is true, then access to the registration table is synchronized.
    static int get_phase_id(const char* phase_name, bool may_exist, bool use_strdup, bool sync) NOT_JFR_RETURN_(-1);

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

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

src/hotspot/share/jvmci/jvmciCompilerToVM.cpp:

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

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

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

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

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

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

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

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

Configuration enabled
default false
profiling false

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

Examples 3
bci int
13
callee CalleeMethod
descriptor string
()Ljava/lang/String;
name string
getValue
type string
jdk/jfr/SettingControl
caller Method
descriptor string
(Ljava/lang/String;)V
hidden boolean
false
modifiers int
1
name string
setValue
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
16
name string
jdk/jfr/internal/Control
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
25.0.3
name string
jdk/jfr/internal
compileId uint
1386
message string
no static binding
startTime long: millis
370286845
succeeded boolean
false
bci int
4
callee CalleeMethod
descriptor string
(Ljava/lang/Object;JB)V
name string
putByte
type string
jdk/internal/misc/Unsafe
caller Method
descriptor string
(JB)V
hidden boolean
false
modifiers int
1
name string
putByte
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
25.0.3
name string
jdk/internal/misc
compileId uint
1386
message string
intrinsic
startTime long: millis
357500248
succeeded boolean
true
bci int
47
callee CalleeMethod
descriptor string
(Ljava/lang/String;)Ljava/lang/StringBuilder;
name string
append
type string
java/lang/StringBuilder
caller Method
descriptor string
(Ljava/lang/String;)V
hidden boolean
false
modifiers int
1
name string
setValue
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
16
name string
jdk/jfr/internal/Control
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
25.0.3
name string
jdk/jfr/internal
compileId uint
1417
message string
inline
startTime long: millis
381479143
succeeded boolean
true

Deoptimization

default profiling startTime eventThread stackTrace 14 17 21 25 26 27

Category: Java Virtual Machine / Compiler

Code Context

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

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

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

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

Configuration enabled stackTrace
default true false
profiling true true

Field Type Description
compileId uint Compilation Identifier
compiler CompilerType Compiler
method Method Method
lineNumber int Line Number
bci int Bytecode Index
instruction Bytecode Instruction
reason DeoptimizationReason Reason
action DeoptimizationAction Action

Examples 3
action DeoptimizationAction
maybe_recompile
bci int
63
compileId uint
1066
compiler CompilerType
c2
instruction Bytecode
invokevirtual
lineNumber int
579
method Method
descriptor string
(Ljava/lang/Object;)Ljava/util/HashMap$Node;
hidden boolean
false
modifiers int
16
name string
getNode
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/HashMap
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util
reason DeoptimizationReason
bimorphic_or_optimized_type_check
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
63
lineNumber int
579
method Method
descriptor string
(Ljava/lang/Object;)Ljava/util/HashMap$Node;
hidden boolean
false
modifiers int
16
name string
getNode
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/HashMap
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
4088853770
action DeoptimizationAction
maybe_recompile
bci int
4
compileId uint
1278
compiler CompilerType
c2
instruction Bytecode
invokeinterface
lineNumber int
1079
method Method
descriptor string
()Z
hidden boolean
false
modifiers int
1
name string
hasNext
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/util/Collections$UnmodifiableCollection$1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util
reason DeoptimizationReason
class_check
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
4
lineNumber int
1079
method Method
descriptor string
()Z
hidden boolean
false
modifiers int
1
name string
hasNext
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/util/Collections$UnmodifiableCollection$1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
375948393
action DeoptimizationAction
maybe_recompile
bci int
4
compileId uint
1162
compiler CompilerType
c2
instruction Bytecode
invokeinterface
lineNumber int
1079
method Method
descriptor string
()Z
hidden boolean
false
modifiers int
1
name string
hasNext
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/util/Collections$UnmodifiableCollection$1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util
reason DeoptimizationReason
class_check
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
4
lineNumber int
1079
method Method
descriptor string
()Z
hidden boolean
false
modifiers int
1
name string
hasNext
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/util/Collections$UnmodifiableCollection$1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
387787573

CompilerStatistics

default profiling startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Compiler

Code Context

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

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

TRACE_REQUEST_FUNC(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());

Configuration enabled period
default true 1000 ms
profiling true 1000 ms

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

Examples 3
bailoutCount int
2
compileCount int
31277
invalidatedCount int
0
nmethodCodeSize ulong: bytes
43254568
nmethodsSize ulong: bytes
63822688
osrBytesCompiled ulong: bytes
0
osrCompileCount int
305
peakTimeSpent long: millis
981
standardBytesCompiled ulong: bytes
0
standardCompileCount int
30972
startTime long: millis
66740944149
totalTimeSpent long: millis
84448
bailoutCount int
7
compileCount int
2899
invalidatedCount int
0
nmethodCodeSize ulong: bytes
3858864
nmethodsSize ulong: bytes
5216992
osrBytesCompiled ulong: bytes
0
osrCompileCount int
19
peakTimeSpent long: millis
199
standardBytesCompiled ulong: bytes
0
standardCompileCount int
2880
startTime long: millis
11653519483
totalTimeSpent long: millis
2791
bailoutCount int
2
compileCount int
27455
invalidatedCount int
0
nmethodCodeSize ulong: bytes
40354144
nmethodsSize ulong: bytes
57603840
osrBytesCompiled ulong: bytes
0
osrCompileCount int
290
peakTimeSpent long: millis
745
standardBytesCompiled ulong: bytes
0
standardCompileCount int
27165
startTime long: millis
64465296880
totalTimeSpent long: millis
68751

CompilerConfiguration

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

Category: Java Virtual Machine / Compiler

Code Context

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

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

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

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

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
threadCount int Thread Count
tieredCompilation boolean Tiered Compilation

Examples 3
startTime long: millis
25067034466
threadCount int
3
tieredCompilation boolean
true
startTime long: millis
63705127639
threadCount int
3
tieredCompilation boolean
true
startTime long: millis
35856198868
threadCount int
3
tieredCompilation boolean
true

JVM: Diagnostics

SyncOnValueBasedClass

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

Category: Java Virtual Machine / Diagnostics

Code Context

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

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

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

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

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

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

Configuration enabled stackTrace
default true true
profiling true true

Field Type Description
valueBasedClass Class Value Based Class

Examples 3
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
17
lineNumber int
296
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
triggerSyncOnValueBased
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
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
1467544460
valueBasedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Integer
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
17
lineNumber int
296
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
triggerSyncOnValueBased
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
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
1294770152
valueBasedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Integer
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
56
lineNumber int
300
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
triggerSyncOnValueBased
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
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
1219761027
valueBasedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Long
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang

HeapDump

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

Category: Java Virtual Machine / Diagnostics

Code Context

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

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

  _large_object_list->drain(cl);
}

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

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

  AbstractCompressor* compressor = NULL;

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

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

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

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

Examples 3
destination string
/tmp/jfr_sample_heap_365919713268.hprof
gcBeforeDump boolean
true
onOutOfMemoryError boolean
false
size long
14269007
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/String;Z)V
hidden boolean
false
modifiers int
258
name string
dumpHeap0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
com/sun/management/internal/HotSpotDiagnostic
package Package
exported boolean
false
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.management
name string
jdk.management
version string
25.0.3
name string
com/sun/management/internal
type FrameType
Native
truncated boolean
false
startTime long: millis
1477224818
destination string
/tmp/jfr_sample_heap_277286644011.hprof
gcBeforeDump boolean
true
onOutOfMemoryError boolean
false
size long
14267337
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/String;Z)V
hidden boolean
false
modifiers int
258
name string
dumpHeap0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
com/sun/management/internal/HotSpotDiagnostic
package Package
exported boolean
false
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.management
name string
jdk.management
version string
25.0.3
name string
com/sun/management/internal
type FrameType
Native
truncated boolean
false
startTime long: millis
1226005000
destination string
/tmp/jfr_sample_heap_332752774776.hprof
gcBeforeDump boolean
true
onOutOfMemoryError boolean
false
size long
15848980
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/String;Z)V
hidden boolean
false
modifiers int
258
name string
dumpHeap0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
com/sun/management/internal/HotSpotDiagnostic
package Package
exported boolean
false
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.management
name string
jdk.management
version string
25.0.3
name string
com/sun/management/internal
type FrameType
Native
truncated boolean
false
startTime long: millis
1300675382

JVM: Flag

IntFlagChanged

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Code Context

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

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

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

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

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

Configuration enabled
default true
profiling true

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

Examples 3
name string
HeapDumpGzipLevel
newValue int
0
oldValue int
1
origin FlagValueOrigin
Management
startTime long: millis
1250655187
name string
HeapDumpGzipLevel
newValue int
0
oldValue int
1
origin FlagValueOrigin
Management
startTime long: millis
1178244990
name string
HeapDumpGzipLevel
newValue int
0
oldValue int
1
origin FlagValueOrigin
Management
startTime long: millis
1417934571

UnsignedIntFlagChanged

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Code Context

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

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

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

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

Configuration enabled
default true
profiling true

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

Examples 3
name string
FullGCHeapDumpLimit
newValue uint
1
oldValue uint
0
origin FlagValueOrigin
Management
startTime long: millis
1417995725
name string
FullGCHeapDumpLimit
newValue uint
1
oldValue uint
0
origin FlagValueOrigin
Management
startTime long: millis
1250685894
name string
FullGCHeapDumpLimit
newValue uint
1
oldValue uint
0
origin FlagValueOrigin
Management
startTime long: millis
1178263398

LongFlagChanged

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Code Context

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

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

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

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

Configuration enabled
default true
profiling true

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 26 27

Category: Java Virtual Machine / Flag

Code Context

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

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

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

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

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

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

Configuration enabled
default true
profiling true

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

Examples 3
name string
SoftMaxHeapSize
newValue ulong
1863319552
oldValue ulong
4192206848
origin FlagValueOrigin
Management
startTime long: millis
1178352732
name string
SoftMaxHeapSize
newValue ulong
4192206848
oldValue ulong
2096103424
origin FlagValueOrigin
Management
startTime long: millis
1418141488
name string
MaxHeapFreeRatio
newValue ulong
70
oldValue ulong
75
origin FlagValueOrigin
Management
startTime long: millis
1249782462

DoubleFlagChanged

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Code Context

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

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

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

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

Configuration enabled
default true
profiling true

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

Examples 3
name string
G1PeriodicGCSystemLoadThreshold
newValue double
0.0
oldValue double
0.5
origin FlagValueOrigin
Management
startTime long: millis
1250579165
name string
G1PeriodicGCSystemLoadThreshold
newValue double
0.5
oldValue double
0.0
origin FlagValueOrigin
Management
startTime long: millis
1417842699
name string
G1PeriodicGCSystemLoadThreshold
newValue double
0.0
oldValue double
0.5
origin FlagValueOrigin
Management
startTime long: millis
1178176226

BooleanFlagChanged

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Code Context

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

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

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

    return JVMFlag::SUCCESS;
  }

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

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

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

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

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

Configuration enabled
default true
profiling true

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

Examples 3
name string
PrintConcurrentLocks
newValue boolean
true
oldValue boolean
false
origin FlagValueOrigin
Management
startTime long: millis
1177844918
name string
PrintConcurrentLocks
newValue boolean
false
oldValue boolean
true
origin FlagValueOrigin
Management
startTime long: millis
1249615280
name string
PrintConcurrentLocks
newValue boolean
false
oldValue boolean
true
origin FlagValueOrigin
Management
startTime long: millis
1417555723

StringFlagChanged

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Code Context

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

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

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

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

Configuration enabled
default true
profiling true

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

Examples 3
name string
HeapDumpPath
newValue string
/tmp/jfr_heap
oldValue string
null
origin FlagValueOrigin
Management
startTime long: millis
1249818519
name string
HeapDumpPath
newValue string
/tmp/jfr_heap
oldValue string
null
origin FlagValueOrigin
Management
startTime long: millis
1178063076
name string
HeapDumpPath
newValue string
/tmp/jfr_heap
oldValue string
null
origin FlagValueOrigin
Management
startTime long: millis
1417756237

IntFlag

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

Category: Java Virtual Machine / Flag

Configuration enabled period
default true beginChunk
profiling true beginChunk

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

Examples 3
name string
JavaPriority7_To_OSPriority
origin FlagValueOrigin
Default
startTime long: millis
9232395732
value int
-1
name string
JavaPriority10_To_OSPriority
origin FlagValueOrigin
Default
startTime long: millis
9176490584
value int
-1
name string
ScavengeALotInterval
origin FlagValueOrigin
Default
startTime long: millis
373491215
value int
1

UnsignedIntFlag

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

Category: Java Virtual Machine / Flag

Configuration enabled period
default true beginChunk
profiling true beginChunk

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

Examples 3
name string
ParallelGCThreads
origin FlagValueOrigin
Default
startTime long: millis
9232414731
value uint
4
name string
PLABWeight
origin FlagValueOrigin
Default
startTime long: millis
384720190
value uint
75
name string
MaxMetaspaceFreeRatio
origin FlagValueOrigin
Default
startTime long: millis
8304358787
value uint
70

LongFlag

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

Category: Java Virtual Machine / Flag

Configuration enabled period
default true beginChunk
profiling true beginChunk

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

Examples 3
name string
ArrayCopyLoadStoreMaxElem
origin FlagValueOrigin
Default
startTime long: millis
373547320
value long
8
name string
MaxInlineLevel
origin FlagValueOrigin
Default
startTime long: millis
384734848
value long
15
name string
Tier4InvocationThreshold
origin FlagValueOrigin
Default
startTime long: millis
360289394
value long
5000

UnsignedLongFlag

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

Category: Java Virtual Machine / Flag

Configuration enabled period
default true beginChunk
profiling true beginChunk

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

Examples 3
name string
AdaptiveSizeMajorGCDecayTimeScale
origin FlagValueOrigin
Default
startTime long: millis
373576184
value ulong
10
name string
HeapBaseMinAddress
origin FlagValueOrigin
Default
startTime long: millis
384781696
value ulong
2147483648
name string
MarkStackSizeMax
origin FlagValueOrigin
Default
startTime long: millis
360321051
value ulong
536870912

DoubleFlag

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

Category: Java Virtual Machine / Flag

Configuration enabled period
default true beginChunk
profiling true beginChunk

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

Examples 3
name string
CompileThresholdScaling
origin FlagValueOrigin
Default
startTime long: millis
27709639694
value double
1.0
name string
InitialRAMPercentage
origin FlagValueOrigin
Default
startTime long: millis
360329304
value double
1.5625
name string
MinInlineFrequencyRatio
origin FlagValueOrigin
Default
startTime long: millis
8304421404
value double
0.0085

BooleanFlag

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

Category: Java Virtual Machine / Flag

Configuration enabled period
default true beginChunk
profiling true beginChunk

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

Examples 3
name string
TraceRangeCheckElimination
origin FlagValueOrigin
Default
startTime long: millis
384797685
value boolean
false
name string
UseC1Optimizations
origin FlagValueOrigin
Default
startTime long: millis
373612261
value boolean
true
name string
PrintOptoInlining
origin FlagValueOrigin
Default
startTime long: millis
360359018
value boolean
false

StringFlag

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

Category: Java Virtual Machine / Flag

Configuration enabled period
default true beginChunk
profiling true beginChunk

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

Examples 3
name string
FlightRecorderOptions
origin FlagValueOrigin
Default
startTime long: millis
360412769
value string
null
name string
MallocTraceDumpFilter
origin FlagValueOrigin
Default
startTime long: millis
9176657116
value string
name string
MallocTraceDumpDelay
origin FlagValueOrigin
Default
startTime long: millis
8304527763
value string
1h

JVM: GC: Collector

GarbageCollection

default profiling startTime duration 11 17 21 25 26 27

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();
  }
}

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

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

Examples 3
cause GCCause
G1 Evacuation Pause
gcId uint
93
longestPause Tickspan
30461615
name GCName
G1New
startTime long: millis
17691188046
sumOfPauses Tickspan
30461615
cause GCCause
G1 Evacuation Pause
gcId uint
11
longestPause Tickspan
1581447
name GCName
G1New
startTime long: millis
719046256
sumOfPauses Tickspan
1581447
cause GCCause
Allocation Failure
gcId uint
1
longestPause Tickspan
7248035
name GCName
ParallelScavenge
startTime long: millis
1052335644
sumOfPauses Tickspan
7248035

SystemGC

default profiling startTime duration eventThread stackTrace 17 21 25 26 27

Category: Java Virtual Machine / GC / Collector

Code Context

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

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

    event.commit();
  }
JVM_END


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


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


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

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

Field Type Description
invokedConcurrent boolean Invoked Concurrent

Examples 3
invokedConcurrent boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
257
name string
gc
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Runtime
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
26405064469
invokedConcurrent boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
257
name string
gc
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Runtime
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
88065248343
invokedConcurrent boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
257
name string
gc
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Runtime
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
3654695862

ParallelOldGarbageCollection

default profiling startTime duration 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Collector

Appearing in: linux_ParallelGC

Missing in: 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);

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

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

Examples 2
densePrefix ulong: address
30223630336
gcId uint
25
startTime long: millis
16948436382
densePrefix ulong: address
30173822976
gcId uint
78
startTime long: millis
2368431963

YoungGarbageCollection

default profiling startTime duration 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Collector

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: 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();

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
tenuringThreshold uint Tenuring Threshold

Examples 3
gcId uint
45
startTime long: millis
6434722828
tenuringThreshold uint
15
gcId uint
27
startTime long: millis
18081294321
tenuringThreshold uint
1
gcId uint
2
startTime long: millis
577303724
tenuringThreshold uint
1

OldGarbageCollection

default profiling startTime duration 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Collector

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: 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());

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier

Examples 3
gcId uint
61
startTime long: millis
46694351700
gcId uint
192
startTime long: millis
36851841875
gcId uint
197
startTime long: millis
3527959007

G1GarbageCollection

default profiling startTime duration 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Collector

Appearing in: linux_G1GC

Missing in: linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Extra information specific to G1 Young Garbage Collections

Code Context

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

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

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

void G1NewTracer::send_g1_young_gc_event() {
  // Check that the pause type has been updated to something valid for this event.
  G1GCPauseTypeHelper::assert_is_young_pause(_pause);

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

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

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
type G1YCType Type

Examples 2
gcId uint
54
startTime long: millis
7204362262
type G1YCType
Concurrent Start
gcId uint
96
startTime long: millis
2429718633
type G1YCType
Normal

JVM: GC: Configuration

GCConfiguration

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

Category: Java Virtual Machine / GC / Configuration

The configuration of the garbage collector

Code Context

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

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

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

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

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

Configuration enabled period
default true everyChunk
profiling true everyChunk

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

Examples 3
concurrentGCThreads uint
0
gcTimeRatio uint
99
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
ParallelOld
parallelGCThreads uint
4
pauseTarget long: millis
-9223372036854775808
startTime long: millis
66608370437
usesDynamicGCThreads boolean
true
youngCollector GCName
ParallelScavenge
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
118407603804
usesDynamicGCThreads boolean
true
youngCollector GCName
G1New
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
25089879886
usesDynamicGCThreads boolean
true
youngCollector GCName
G1New

GCSurvivorConfiguration

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

Category: Java Virtual Machine / GC / Configuration

The configuration of the survivors of garbage collection

Code Context

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

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

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

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

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

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
maxTenuringThreshold ubyte Maximum Tenuring Threshold Upper limit for the age of how old objects to keep in the survivor area
initialTenuringThreshold ubyte Initial Tenuring Threshold Initial age limit for how old objects to keep in survivor area

Examples 3
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
383871712
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
87120123835
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
9498823383

GCTLABConfiguration

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

Category: Java Virtual Machine / GC / Configuration

The configuration of the Thread Local Allocation Buffers (TLABs)

Code Context

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

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

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

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

TRACE_REQUEST_FUNC(GCSurvivorConfiguration) {
  GCSurvivorConfiguration conf;
  EventGCSurvivorConfiguration event;
  event.set_maxTenuringThreshold(conf.max_tenuring_threshold());
  event.set_initialTenuringThreshold(conf.initial_tenuring_threshold());

Configuration enabled period
default true beginChunk
profiling true beginChunk

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

Examples 3
minTLABSize ulong: bytes
2048
startTime long: millis
383874197
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
minTLABSize ulong: bytes
2048
startTime long: millis
57951448442
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
minTLABSize ulong: bytes
2048
startTime long: millis
99418708745
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true

GCHeapConfiguration

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

Category: Java Virtual Machine / GC / Configuration

The configuration of the garbage collected heap

Code Context

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

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

  event.commit();
}

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

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

TRACE_REQUEST_FUNC(YoungGenerationConfiguration) {

Configuration enabled period
default true beginChunk
profiling true beginChunk

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

Examples 3
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
262144000
maxSize ulong: bytes
4192206848
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
28398106562
usesCompressedOops boolean
true
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
8329379536
usesCompressedOops boolean
true
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
126559204325
usesCompressedOops boolean
true

YoungGenerationConfiguration

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

Category: Java Virtual Machine / GC / Configuration

The configuration of the young generation of the garbage collected heap

Code Context

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

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

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

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

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

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
minSize ulong: bytes Minimum Young Generation Size
maxSize ulong: bytes Maximum Young Generation Size
newRatio uint New Ratio The size of the young generation relative to the tenured generation

Examples 3
maxSize ulong: bytes
2514485248
minSize ulong: bytes
1363144
newRatio uint
2
startTime long: millis
52991667198
maxSize ulong: bytes
2514485248
minSize ulong: bytes
1363144
newRatio uint
2
startTime long: millis
16563562617
maxSize ulong: bytes
1396703232
minSize ulong: bytes
85983232
newRatio uint
2
startTime long: millis
51844120077

JVM: GC: Detailed

ZThreadDebug

internal startTime duration eventThread 18 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Temporary latency measurements used during development and debugging of ZGC

Only valid for the ZGC.

Code Context

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

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

  NoSafepointVerifier nsv;

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

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

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

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

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

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

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

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

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

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

G1MMU

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_G1GC

Missing in: 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();
  }
}

Configuration enabled
default true
profiling true

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

Examples 2
gcId uint
31
gcTime long: millis
4
pauseTarget long: millis
200
startTime long: millis
1625661119
timeSlice long: millis
201
gcId uint
14
gcTime long: millis
43
pauseTarget long: millis
200
startTime long: millis
1477245416
timeSlice long: millis
201

EvacuationInformation

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_G1GC

Missing in: linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Code Context

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

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

  G1GCPauseTypeHelper::assert_is_young_pause(_pause);

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

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

Configuration enabled
default true
profiling true

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

Examples 2
allocationRegions uint
4
allocationRegionsUsedAfter ulong: bytes
6725248
allocationRegionsUsedBefore ulong: bytes
1597040
bytesCopied ulong: bytes
5128208
cSetRegions uint
73
cSetUsedAfter ulong: bytes
0
cSetUsedBefore ulong: bytes
152831824
gcId uint
21
regionsFreed uint
73
startTime long: millis
1312889505
allocationRegions uint
2
allocationRegionsUsedAfter ulong: bytes
1279736
allocationRegionsUsedBefore ulong: bytes
0
bytesCopied ulong: bytes
1279736
cSetRegions uint
30
cSetUsedAfter ulong: bytes
0
cSetUsedBefore ulong: bytes
62066288
gcId uint
56
regionsFreed uint
30
startTime long: millis
7324944742

ObjectCountAfterGC

startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: 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/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

Configuration enabled
default false
profiling false

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

Examples 3
count long
90374
gcId uint
15
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
24
name string
java/util/regex/Pattern$TreeInfo
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util/regex
startTime long: millis
1595114687
totalSize ulong: bytes
2168976
count long
843
gcId uint
23
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/jfr/ValueDescriptor
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.jfr
name string
jdk.jfr
version string
25.0.3
name string
jdk/jfr
startTime long: millis
1428256829
totalSize ulong: bytes
33720
count long
157071
gcId uint
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
25.0.3
name string
java/net
hidden boolean
true
modifiers int
4112
name string
akka.actor.Props$$$Lambda/0x000000002d78e000
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
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
akka/actor
startTime long: millis
8832793279
totalSize ulong: bytes
2513136

G1EvacuationYoungStatistics

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_G1GC

Missing in: 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();

Configuration enabled
default true
profiling true

Field Type Description
statistics G1EvacuationStatistics struct Evacuation Statistics

Examples 2
startTime long: millis
23515595934
statistics G1EvacuationStatistics
allocated ulong: bytes
8388608
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
109
regionEndWaste ulong: bytes
0
regionsRefilled uint: bytes
4
undoWaste ulong: bytes
0
used ulong: bytes
8388568
wasted ulong: bytes
40
startTime long: millis
614499848
statistics G1EvacuationStatistics
allocated ulong: bytes
3431968
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
6
regionEndWaste ulong: bytes
0
regionsRefilled uint: bytes
2
undoWaste ulong: bytes
0
used ulong: bytes
3056624
wasted ulong: bytes
32784

G1EvacuationOldStatistics

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_G1GC

Missing in: 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,

Configuration enabled
default true
profiling true

Field Type Description
statistics G1EvacuationStatistics struct Evacuation Statistics

Examples 2
startTime long: millis
27706573462
statistics G1EvacuationStatistics
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
128
regionEndWaste ulong: bytes
0
regionsRefilled uint: bytes
0
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0
startTime long: millis
2712837144
statistics G1EvacuationStatistics
allocated ulong: bytes
0
directAllocated ulong: bytes
2792048
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
123
regionEndWaste ulong: bytes
32
regionsRefilled uint: bytes
2
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0

G1BasicIHOP

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_G1GC

Missing in: 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();

Configuration enabled
default true
profiling true

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

Examples 2
currentOccupancy ulong: bytes
27038016
gcId uint
62
lastMarkingDuration long: millis
200
recentAllocationRate double: bytes-per-second
0.0
recentMutatorAllocationSize ulong: bytes
0
recentMutatorDuration long: millis
98
startTime long: millis
7843066307
targetOccupancy ulong: bytes
125829120
threshold ulong: bytes
0
thresholdPercentage float: percentage
0.0
currentOccupancy ulong: bytes
13287272
gcId uint
126
lastMarkingDuration long: millis
40
recentAllocationRate double: bytes-per-second
1.5829618055923047E9
recentMutatorAllocationSize ulong: bytes
3151840
recentMutatorDuration long: millis
1
startTime long: millis
2762330858
targetOccupancy ulong: bytes
29360128
threshold ulong: bytes
13212057
thresholdPercentage float: percentage
0.45

G1AdaptiveIHOP

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_G1GC

Missing in: 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();

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier
threshold ulong: bytes Threshold Current IHOP Threshold
thresholdPercentage float: percentage Threshold Current IHOP threshold in percent of the internal target occupancy
ihopTargetOccupancy ulong: bytes IHOP Target Occupancy Internal target old generation occupancy to reach at the start of mixed GC
currentOccupancy ulong: bytes Current Occupancy Current old generation occupancy
additionalBufferSize ulong: bytes Additional Buffer Additional buffer size
predictedAllocationRate double: bytes-per-second Predicted Allocation Rate Current predicted allocation rate for the mutator in bytes/second
predictedMarkingDuration long: millis Predicted Marking Duration Current predicted time from the end of the last concurrent start to the first mixed GC
predictionActive boolean Prediction Active Indicates whether the adaptive IHOP prediction is active

Examples 2
additionalBufferSize ulong: bytes
511705088
currentOccupancy ulong: bytes
187603328
gcId uint
77
ihopTargetOccupancy ulong: bytes
914463129
predictedAllocationRate double: bytes-per-second
4.3104568865833527E8
predictedMarkingDuration long: millis
350
predictionActive boolean
true
startTime long: millis
10199255233
threshold ulong: bytes
251778587
thresholdPercentage float: percentage
0.2753294
additionalBufferSize ulong: bytes
8388608
currentOccupancy ulong: bytes
13443408
gcId uint
81
ihopTargetOccupancy ulong: bytes
27892121
predictedAllocationRate double: bytes-per-second
1.1208461132017562E9
predictedMarkingDuration long: millis
81
predictionActive boolean
false
startTime long: millis
2247842567
threshold ulong: bytes
13212057
thresholdPercentage float: percentage
0.4736842

PromoteObjectInNewPLAB

profiling startTime eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_G1GC, linux_ParallelGC

Missing in: 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();
  }
}

Configuration enabled
default false
profiling true

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
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
24
plabSize ulong: bytes
32760
startTime long: millis
1056625398
tenured boolean
false
tenuringAge uint
0
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
3608
plabSize ulong: bytes
43688
startTime long: millis
604456680
tenured boolean
false
tenuringAge uint
0
gcId uint
2
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
48
plabSize ulong: bytes
4096
startTime long: millis
577722285
tenured boolean
true
tenuringAge uint
1

PromoteObjectOutsidePLAB

profiling startTime eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_G1GC, linux_ParallelGC

Missing in: 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 {

Configuration enabled
default false
profiling true

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
gcId uint
41
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
8208
startTime long: millis
6096968092
tenured boolean
true
tenuringAge uint
0
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
575392589
tenured boolean
false
tenuringAge uint
0
gcId uint
2
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
60224
startTime long: millis
1320169429
tenured boolean
false
tenuringAge uint
1

PromotionFailed

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Promotion of an object failed

Code Context

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

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

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

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

Configuration enabled
default true
profiling true

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 26 27

Category: Java Virtual Machine / GC / Detailed

Evacuation of an object failed

Code Context

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

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

    e.set_cSetRegions(info->collectionset_regions());
    e.set_cSetUsedBefore(info->collectionset_used_before());
    e.set_cSetUsedAfter(info->collectionset_used_after());
    e.set_allocationRegions(info->allocation_regions());
    e.set_allocationRegionsUsedBefore(info->alloc_regions_used_before());
    e.set_allocationRegionsUsedAfter(info->alloc_regions_used_before() + info->bytes_used());
    e.set_bytesCopied(info->bytes_used());
    e.set_regionsFreed(info->regions_freed());
    e.commit();
  }
}

void G1NewTracer::send_evacuation_failed_event(const EvacuationFailedInfo& ef_info) const {
  EventEvacuationFailed e;
  if (e.should_commit()) {
    // Create JFR structured failure data
    JfrStructCopyFailed evac_failed;
    evac_failed.set_objectCount(ef_info.failed_count());
    evac_failed.set_firstSize(ef_info.first_size());
    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();

Configuration enabled
default true
profiling true

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

ConcurrentModeFailure

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_G1GC

Missing in: linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Concurrent Mode failed

Code Context

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

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

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

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

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

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier

Examples 2
gcId uint
68
startTime long: millis
9242546134
gcId uint
1020
startTime long: millis
13479120187

AllocationRequiringGC

startTime eventThread stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: 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/allocTracer.cpp:

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

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

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

Configuration enabled stackTrace
default false true
profiling false true

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

Examples 3
gcId uint
12
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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
756607233
gcId uint
12
size ulong: bytes
24
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
56
lineNumber int
250
method Method
descriptor string
(Ljava/util/regex/Pattern;Ljava/lang/CharSequence;)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
17
name string
java/util/regex/Matcher
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util/regex
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
1399950138
gcId uint
56
size ulong: bytes
24
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
55
method Method
descriptor string
(JIJJ)V
hidden boolean
false
modifiers int
1
name string
incrementRelationshipCount
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
25.0.3
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/neo4j/storageengine/api/CountsDelta
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
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
org/neo4j/storageengine/api
type FrameType
Inlined
truncated boolean
false
startTime long: millis
41370626668

TenuringDistribution

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_G1GC, linux_SerialGC

Missing in: 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();
}

Configuration enabled
default true
profiling true

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

Examples 3
age uint
11
gcId uint
8
size ulong: bytes
0
startTime long: millis
1160879863
age uint
14
gcId uint
5
size ulong: bytes
0
startTime long: millis
1498636717
age uint
12
gcId uint
0
size ulong: bytes
0
startTime long: millis
383576560

G1HeapRegionTypeChange

startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_G1GC

Missing in: 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();
  }
}

Configuration enabled
default false
profiling false

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

Examples 2
from G1HeapRegionType
Old
index uint
3
start ulong: address
30173822976
startTime long: millis
382802253
to G1HeapRegionType
Free
used ulong: bytes
621440
from G1HeapRegionType
Eden
index uint
11
start ulong: address
30190600192
startTime long: millis
1048746147
to G1HeapRegionType
Free
used ulong: bytes
0

ObjectCount

startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: 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/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

Configuration enabled period
default false everyChunk
profiling false everyChunk

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

Examples 3
count long
2435
gcId uint
0
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
24
name string
java/util/ImmutableCollections$List12
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util
startTime long: millis
379054085
totalSize ulong: bytes
38960
count long
556
gcId uint
0
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[Ljava/lang/String;
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
startTime long: millis
390792545
totalSize ulong: bytes
21456
count long
935
gcId uint
0
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/LinkedHashMap
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util
startTime long: millis
368313832
totalSize ulong: bytes
52360

G1HeapRegionInformation

startTime duration every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_G1GC

Missing in: 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);

Configuration enabled period
default false everyChunk
profiling false everyChunk

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

Examples 2
index uint
0
start ulong: address
30167531520
startTime long: millis
8967484713
type G1HeapRegionType
Old
used ulong: bytes
2097136
index uint
8
start ulong: address
30184308736
startTime long: millis
8180853364
type G1HeapRegionType
Free
used ulong: bytes
0

ZAllocationStall

default profiling startTime duration eventThread 15 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

Missing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Time spent waiting for memory to become available

Code Context

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

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

  // Success
  return true;
}

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

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

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

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

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

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
type ZPageTypeType Type
size ulong: bytes Size

Examples 1
size ulong: bytes
2097152
startTime long: millis
60001939937
type ZPageTypeType
Small

ZPageAllocation

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

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

Missing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Allocation of a ZPage

Code Context

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

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

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

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

  // Try satisfy stalled allocations
  satisfy_stalled();
}

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

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

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

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

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

Examples 2
committed ulong: bytes
0
nonBlocking boolean
false
size ulong: bytes
2097152
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
80
lineNumber int
77
method Method
descriptor string
(IF)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
17
name string
jdk/internal/classfile/impl/EntryMap
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
25.0.3
name string
jdk/internal/classfile/impl
type FrameType
Inlined
truncated boolean
false
startTime long: millis
568226521
type ZPageTypeType
Small
committed ulong: bytes
0
nonBlocking boolean
false
size ulong: bytes
2097152
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
10
lineNumber int
157
method Method
descriptor string
(I)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/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
25.0.3
name string
java/util
type FrameType
Inlined
truncated boolean
false
startTime long: millis
1085487676
type ZPageTypeType
Small

ZRelocationSet

default profiling startTime duration eventThread 15 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

Missing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Code Context

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

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

ZRelocationSetSelector::ZRelocationSetSelector() :
    _small("Small", ZPageTypeSmall, ZPageSizeSmall, ZObjectSizeLimitSmall),
    _medium("Medium", ZPageTypeMedium, ZPageSizeMedium, ZObjectSizeLimitMedium),
    _large("Large", ZPageTypeLarge, 0 /* page_size */, 0 /* object_size_limit */),
    _empty_pages() {}

void ZRelocationSetSelector::select() {
  // Select pages to relocate. The resulting relocation set will be
  // sorted such that medium pages comes first, followed by small
  // pages. Pages within each page group will be semi-sorted by live
  // bytes in ascending order. Relocating pages in this order allows
  // us to start reclaiming memory more quickly.

  EventZRelocationSet event;

  // Select pages from each group
  _large.select();
  _medium.select();
  _small.select();

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

ZRelocationSetSelectorStats ZRelocationSetSelector::stats() const {

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

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

Examples 2
empty ulong: bytes
33554432
relocate ulong: bytes
16018920
startTime long: millis
1473837243
total ulong: bytes
297795584
empty ulong: bytes
0
relocate ulong: bytes
1560
startTime long: millis
36505574332
total ulong: bytes
4194304

ZRelocationSetGroup

default profiling startTime duration eventThread 15 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

Missing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Code Context

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

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

  // Update statistics
  _stats._relocate = selected_live_bytes;

  log_trace(gc, reloc)("Relocation Set (%s Pages): %d->%d, %d skipped, " SIZE_FORMAT " forwarding entries",
                       _name, selected_from, selected_to, npages - selected_from, selected_forwarding_entries);
}

void ZRelocationSetSelectorGroup::select() {
  if (is_disabled()) {
    return;
  }

  EventZRelocationSetGroup event;

  if (is_selectable()) {
    select_inner();
  }

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

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

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

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

Examples 2
empty ulong: bytes
0
relocate ulong: bytes
0
startTime long: millis
5198579591
total ulong: bytes
0
type ZPageTypeType
Large
empty ulong: bytes
0
relocate ulong: bytes
0
startTime long: millis
395211002
total ulong: bytes
0
type ZPageTypeType
Small

ZStatisticsCounter

experimental startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

Missing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Code Context

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

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

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

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

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

  EventZStatisticsCounter e;
  if (e.should_commit()) {
    e.set_id(counter.id());
    e.set_increment(increment);
    e.set_value(value);
    e.commit();
  }
}

void ZTracer::send_stat_sampler(const ZStatSampler& sampler, uint64_t value) {
  NoSafepointVerifier nsv;

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

#ifndef SHARE_GC_Z_ZTRACER_INLINE_HPP
#define SHARE_GC_Z_ZTRACER_INLINE_HPP

#include "gc/z/zTracer.hpp"

#include "jfr/jfrEvents.hpp"

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

inline void ZTracer::report_stat_counter(const ZStatCounter& counter, uint64_t increment, uint64_t value) {
  if (EventZStatisticsCounter::is_enabled()) {
    send_stat_counter(counter, increment, value);
  }
}

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

inline void ZTracer::report_thread_phase(const char* name, const Ticks& start, const Ticks& end) {

Configuration enabled threshold
default false 0 ms
profiling false 0 ms

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

Examples 2
id ZStatisticsCounterType
Allocation Rate
increment ulong
2097152
startTime long: millis
911604880
value ulong
37748736
id ZStatisticsCounterType
Allocation Rate
increment ulong
2097152
startTime long: millis
760214173
value ulong
121634816

ZStatisticsSampler

experimental startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

Missing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Code Context

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

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

  EventZStatisticsCounter e;
  if (e.should_commit()) {
    e.set_id(counter.id());
    e.set_increment(increment);
    e.set_value(value);
    e.commit();
  }
}

void ZTracer::send_stat_sampler(const ZStatSampler& sampler, uint64_t value) {
  NoSafepointVerifier nsv;

  EventZStatisticsSampler e;
  if (e.should_commit()) {
    e.set_id(sampler.id());
    e.set_value(value);
    e.commit();
  }
}

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

  EventZThreadPhase e(UNTIMED);

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

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

inline void ZTracer::report_stat_counter(const ZStatCounter& counter, uint64_t increment, uint64_t value) {
  if (EventZStatisticsCounter::is_enabled()) {
    send_stat_counter(counter, increment, value);
  }
}

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

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

inline void ZTracer::report_thread_debug(const char* name, const Ticks& start, const Ticks& end) {

Configuration enabled threshold
default false 0 ms
profiling false 0 ms

Field Type Description
id ZStatisticsSamplerType Id
value ulong Value

Examples 2
id ZStatisticsSamplerType
Concurrent Remap Remembered
startTime long: millis
402837162
value ulong
12449
id ZStatisticsSamplerType
Concurrent Roots JavaThreads
startTime long: millis
418956238
value ulong
55164

ZThreadPhase

experimental startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ZGC

Missing in: 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;

  EventZStatisticsSampler e;
  if (e.should_commit()) {
    e.set_id(sampler.id());
    e.set_value(value);
    e.commit();
  }
}

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

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

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

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

inline void ZTracer::report_stat_counter(const ZStatCounter& counter, uint64_t increment, uint64_t value) {
  if (EventZStatisticsCounter::is_enabled()) {
    send_stat_counter(counter, increment, value);
  }
}

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

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

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

inline ZTraceThreadDebug::ZTraceThreadDebug(const char* name) :

Configuration enabled threshold
default false 0 ms
profiling false 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 2
gcId uint
1
name string
Concurrent Roots OopStorageSet
startTime long: millis
803633263
gcId uint
2
name string
Concurrent Mark Root Colored
startTime long: millis
1264919293

ZUncommit

default profiling startTime duration eventThread 15 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Uncommitting of memory

Code Context

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

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

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

void ZUncommitter::run_service() {
  uint64_t timeout = 0;

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

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

      uncommitted += flushed;

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
uncommitted ulong: bytes Uncommitted

ZUnmap

default profiling startTime duration eventThread 17 21 until JDK 25

Category: Java Virtual Machine / GC / Detailed

Unmapping of memory

Code Context

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

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

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

    _lock.wait();
  }
}

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

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

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

void ZUnmapper::unmap_and_destroy_page(ZPage* page) {

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
unmapped ulong: bytes Unmapped

ShenandoahHeapRegionStateChange

startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ShenandoahGC

Missing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ZGC

Information about a Shenandoah heap region state change

Code Context

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

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

void ShenandoahHeapRegion::do_uncommit() {
  ShenandoahHeap* heap = ShenandoahHeap::heap();
  if (!heap->is_heap_region_special() && !os::uncommit_memory((char *) bottom(), RegionSizeBytes)) {
    report_java_out_of_memory("Unable to uncommit region");
  }
  if (!heap->uncommit_bitmap_slice(this)) {
    report_java_out_of_memory("Unable to uncommit bitmaps for region");
  }
  heap->decrease_committed(ShenandoahHeapRegion::region_size_bytes());
}

void ShenandoahHeapRegion::set_state(RegionState to) {
  EventShenandoahHeapRegionStateChange evt;
  if (evt.should_commit()){
    evt.set_index((unsigned) index());
    evt.set_start((uintptr_t)bottom());
    evt.set_used(used());
    evt.set_from(_state);
    evt.set_to(to);
    evt.commit();
  }
  _state = to;
}

Configuration enabled
default false
profiling false

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

Examples 2
from ShenandoahHeapRegionState
Empty Uncommitted
index uint
3031
start ulong: address
33345765376
startTime long: millis
13050083362
to ShenandoahHeapRegionState
Regular
used ulong: bytes
0
from ShenandoahHeapRegionState
Empty Uncommitted
index uint
3348
start ulong: address
33678163968
startTime long: millis
897069408
to ShenandoahHeapRegionState
Regular
used ulong: bytes
0

ShenandoahHeapRegionInformation

startTime duration every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: linux_ShenandoahGC

Missing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ZGC

Information about a specific heap region in the Shenandoah GC

Code Context

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

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

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

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

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

Configuration enabled period
default false everyChunk
profiling false everyChunk

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

Examples 2
index uint
78
start ulong: address
30249320448
startTime long: millis
374189788
state ShenandoahHeapRegionState
Empty Committed
used ulong: bytes
0
index uint
63
start ulong: address
30233591808
startTime long: millis
15699068551
state ShenandoahHeapRegionState
Empty Uncommitted
used ulong: bytes
0

GCLocker

default profiling startTime eventThread stackTrace 17 21 until JDK 25

Category: Java Virtual Machine / GC / Detailed

Code Context

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

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

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

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

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

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

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

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

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

JVM: GC: Heap

GCHeapSummary

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Heap

Code Context

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

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

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

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

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

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

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

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier
when GCWhen When
heapSpace VirtualSpace struct Heap Space
heapUsed ulong: bytes Heap Used Bytes allocated by objects in the heap

Examples 3
gcId uint
49
heapSpace VirtualSpace
committedEnd ulong: address
30272389120
committedSize ulong: bytes
104857600
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
heapUsed ulong: bytes
87758952
startTime long: millis
6775531901
when GCWhen
Before GC
gcId uint
31
heapSpace VirtualSpace
committedEnd ulong: address
31792824320
committedSize ulong: bytes
1625292800
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
heapUsed ulong: bytes
89186040
startTime long: millis
24234566653
when GCWhen
After GC
gcId uint
33
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
6773680
startTime long: millis
1669948557
when GCWhen
After GC

MetaspaceSummary

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Heap

Code Context

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

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

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

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

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

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier
when GCWhen When
gcThreshold ulong: bytes GC Threshold
metaspace MetaspaceSizes struct Total
dataSpace MetaspaceSizes struct Data
classSpace MetaspaceSizes struct Class

Examples 3
classSpace MetaspaceSizes
committed ulong: bytes
2424832
reserved ulong: bytes
1073741824
used ulong: bytes
2275936
dataSpace MetaspaceSizes
committed ulong: bytes
9633792
reserved ulong: bytes
67108864
used ulong: bytes
9485544
gcId uint
18
gcThreshold ulong: bytes
22020096
metaspace MetaspaceSizes
committed ulong: bytes
12058624
reserved ulong: bytes
1140850688
used ulong: bytes
11761480
startTime long: millis
1073837340
when GCWhen
After GC
classSpace MetaspaceSizes
committed ulong: bytes
6356992
reserved ulong: bytes
1073741824
used ulong: bytes
6223912
dataSpace MetaspaceSizes
committed ulong: bytes
26345472
reserved ulong: bytes
67108864
used ulong: bytes
26126520
gcId uint
39
gcThreshold ulong: bytes
54394880
metaspace MetaspaceSizes
committed ulong: bytes
32702464
reserved ulong: bytes
1140850688
used ulong: bytes
32350432
startTime long: millis
5849088373
when GCWhen
Before GC
classSpace MetaspaceSizes
committed ulong: bytes
6422528
reserved ulong: bytes
1073741824
used ulong: bytes
6220216
dataSpace MetaspaceSizes
committed ulong: bytes
26345472
reserved ulong: bytes
67108864
used ulong: bytes
26136136
gcId uint
14
gcThreshold ulong: bytes
52559872
metaspace MetaspaceSizes
committed ulong: bytes
32768000
reserved ulong: bytes
1140850688
used ulong: bytes
32356352
startTime long: millis
6177916603
when GCWhen
After GC

PSHeapSummary

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Heap

Appearing in: linux_ParallelGC

Missing in: 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();

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier
when GCWhen When
oldSpace VirtualSpace struct Old Space
oldObjectSpace ObjectSpace struct Old Object Space
youngSpace VirtualSpace struct Young Space
edenSpace ObjectSpace struct Eden Space
fromSpace ObjectSpace struct From Space
toSpace ObjectSpace struct To Space

Examples 2
edenSpace ObjectSpace
end ulong: address
33093058560
size ulong: bytes
130023424
start ulong: address
32963035136
used ulong: bytes
0
fromSpace ObjectSpace
end ulong: address
33103544320
size ulong: bytes
10485760
start ulong: address
33093058560
used ulong: bytes
0
gcId uint
6
oldObjectSpace ObjectSpace
end ulong: address
30343692288
size ulong: bytes
176160768
start ulong: address
30167531520
used ulong: bytes
71483952
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
1635436603
toSpace ObjectSpace
end ulong: address
33285996544
size ulong: bytes
31457280
start ulong: address
33254539264
used ulong: bytes
0
when GCWhen
After GC
youngSpace VirtualSpace
committedEnd ulong: address
33285996544
committedSize ulong: bytes
322961408
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
1396703232
start ulong: address
32963035136
edenSpace ObjectSpace
end ulong: address
33478934528
size ulong: bytes
515899392
start ulong: address
32963035136
used ulong: bytes
12571672
fromSpace ObjectSpace
end ulong: address
33491517440
size ulong: bytes
6291456
start ulong: address
33485225984
used ulong: bytes
0
gcId uint
26
oldObjectSpace ObjectSpace
end ulong: address
30343692288
size ulong: bytes
176160768
start ulong: address
30167531520
used ulong: bytes
6528320
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
1580518704
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

G1HeapSummary

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Heap

Appearing in: linux_G1GC

Missing in: 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();
    }
  }

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier
when GCWhen When
edenUsedSize ulong: bytes Eden Used Size
edenTotalSize ulong: bytes Eden Total Size
survivorUsedSize ulong: bytes Survivor Used Size
numberOfRegions uint Number of Regions

Examples 2
edenTotalSize ulong: bytes
16777216
edenUsedSize ulong: bytes
0
gcId uint
12
numberOfRegions uint
37
startTime long: millis
1407768284
survivorUsedSize ulong: bytes
4194304
when GCWhen
After GC
edenTotalSize ulong: bytes
56623104
edenUsedSize ulong: bytes
0
gcId uint
5
numberOfRegions uint
70
startTime long: millis
585475124
survivorUsedSize ulong: bytes
2097152
when GCWhen
After GC

JVM: GC: Metaspace

MetaspaceGCThreshold

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Metaspace

Code Context

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

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

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

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

Configuration enabled
default true
profiling true

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

Examples 3
newValue ulong: bytes
25362432
oldValue ulong: bytes
25034752
startTime long: millis
10496267348
updater GCThresholdUpdater
compute_new_size
newValue ulong: bytes
103350272
oldValue ulong: bytes
73662464
startTime long: millis
20385617037
updater GCThresholdUpdater
compute_new_size
newValue ulong: bytes
271974400
oldValue ulong: bytes
270467072
startTime long: millis
58732549604
updater GCThresholdUpdater
compute_new_size

MetaspaceAllocationFailure

default profiling startTime stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Metaspace

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ZGC

Missing in: 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/memory/metaspaceTracer.cpp:

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

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

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

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

Configuration enabled stackTrace
default true true
profiling true true

Field Type Description
classLoader ClassLoader Class Loader
hiddenClassLoader boolean 15+ Hidden Class Loader
size ulong: bytes Size
metadataType MetadataType Metadata Type
metaspaceObjectType MetaspaceObjectType Metaspace Object Type

Examples 3
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/net
hiddenClassLoader boolean
false
metadataType MetadataType
Metadata
metaspaceObjectType MetaspaceObjectType
TypeArrayU8
size ulong: bytes
88
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
25.0.3
name string
java/lang
type FrameType
Native
truncated boolean
true
startTime long: millis
4063697112
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/net
hiddenClassLoader boolean
false
metadataType MetadataType
Metadata
metaspaceObjectType MetaspaceObjectType
ConstantPool
size ulong: bytes
616
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
25.0.3
name string
java/lang
type FrameType
Native
truncated boolean
true
startTime long: millis
4349270066
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/net
hiddenClassLoader boolean
false
metadataType MetadataType
Metadata
metaspaceObjectType MetaspaceObjectType
ConstantPool
size ulong: bytes
7928
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
25.0.3
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
32124132844

MetaspaceOOM

default profiling startTime stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Metaspace

Code Context

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

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

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

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

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

Configuration enabled stackTrace
default true true
profiling true true

Field Type Description
classLoader ClassLoader Class Loader
hiddenClassLoader boolean 15+ Hidden Class Loader
size ulong: bytes Size
metadataType MetadataType Metadata Type
metaspaceObjectType MetaspaceObjectType Metaspace Object Type

MetaspaceChunkFreeListSummary

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Metaspace

Code Context

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

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

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

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

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

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

Configuration enabled
default true
profiling true

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

Examples 3
gcId uint
20
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
1797711983
when GCWhen
After GC
gcId uint
3
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
594675634
when GCWhen
After GC
gcId uint
12
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
3973150779
when GCWhen
After GC

JVM: GC: Phases

GCPhasePause

default profiling startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Phases

Code Context

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

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

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

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

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

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

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
46
name string
GC Pause
startTime long: millis
6555359692
gcId uint
70
name string
GC Pause
startTime long: millis
2110916406
gcId uint
37
name string
GC Pause
startTime long: millis
26043949087

GCPhasePauseLevel1

default profiling startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Phases

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Missing in: linux_ZGC

Code Context

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

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

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

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

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

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

    switch (phase->level()) {

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
25
name string
Select For Rebuild and Reclaim Empty Regions
startTime long: millis
2776412142
gcId uint
6
name string
Forward
startTime long: millis
1585305531
gcId uint
24
name string
Notify and keep alive finalizable
startTime long: millis
1454989437

GCPhasePauseLevel2

default profiling startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Phases

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC

Missing in: linux_ShenandoahGC, linux_ZGC

Code Context

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

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

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

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

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

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

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

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
25
name string
Notify and keep alive finalizable
startTime long: millis
2775117191
gcId uint
32
name string
Phase 1: Class Unloading and Cleanup
startTime long: millis
1633234919
gcId uint
4
name string
Notify and keep alive finalizable
startTime long: millis
1448429661

GCPhasePauseLevel3

startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Phases

Appearing in: 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_classSpace(to_struct(meta_space_summary.stats().class_space_stats()));
    e.commit();
  }
}

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

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

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

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

Configuration enabled threshold
default false 0 ms
profiling false 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
6
name string
Notify and keep alive finalizable
startTime long: millis
1562368692
gcId uint
33
name string
Notify Soft/WeakReferences
startTime long: millis
5096189252
gcId uint
26
name string
Free Code Blobs
startTime long: millis
1488206988

GCPhasePauseLevel4

startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Phases

Appearing in: linux_G1GC, linux_ParallelGC

Missing in: linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Code Context

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

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

    e.commit();
  }
}

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

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

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

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

Configuration enabled threshold
default false 0 ms
profiling false 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 2
gcId uint
353
name string
Balance queues
startTime long: millis
107717264341
gcId uint
78
name string
Balance queues
startTime long: millis
66993735654

GCPhaseConcurrent

default profiling startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Phases

Appearing in: linux_G1GC, linux_ShenandoahGC, linux_ZGC

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

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

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

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
11
name string
Concurrent Cleanup for Next Mark
startTime long: millis
1354233761
gcId uint
331
name string
Concurrent Mark From Roots
startTime long: millis
5136765132
gcId uint
12
name string
Concurrent cleanup (unload classes)
startTime long: millis
25562268966

GCPhaseConcurrentLevel1

default profiling startTime duration eventThread 15 17 21 25 26 27

Category: Java Virtual Machine / GC / Phases

Appearing in: linux_G1GC, linux_ShenandoahGC, linux_ZGC

Missing in: linux_ParallelGC, linux_SerialGC

Code Context

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

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

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

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

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

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

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
3
name string
Preclean WeakReferences
startTime long: millis
588740154
gcId uint
34
name string
ClassLoaderData
startTime long: millis
53240585189
gcId uint
82
name string
Preclean FinalReferences
startTime long: millis
13813469806

GCPhaseParallel

default profiling startTime duration eventThread 12 17 21 25 26 27

Category: Java Virtual Machine / GC / Phases

Appearing in: linux_G1GC, linux_ShenandoahGC

Missing in: linux_ParallelGC, linux_SerialGC, linux_ZGC

GC phases for parallel workers

Code Context

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

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

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

  FreeRegionList* worker_freelist(uint worker) {
    return &_worker_freelists[worker];
  }

  // Each worker creates a free list for a chunk of the heap. The chunks won't
  // be overlapping so we don't need to do any claiming.
  void work(uint worker_id) {
    Ticks start_time = Ticks::now();
    EventGCPhaseParallel event;

    uint start = worker_id * _worker_chunk_size;
    uint end = MIN2(start + _worker_chunk_size, _hrm->reserved_length());

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

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

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

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

  void print_cycle_on(outputStream* out) const;
  void print_global_on(outputStream* out) const;
};

class ShenandoahWorkerTimingsTracker : public StackObj {
private:
  ShenandoahPhaseTimings*          const _timings;
  ShenandoahPhaseTimings::Phase    const _phase;
  ShenandoahPhaseTimings::ParPhase const _par_phase;
  uint const _worker_id;

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

#endif // SHARE_GC_SHENANDOAH_SHENANDOAHPHASETIMINGS_HPP

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

class ShenandoahConcurrentWorkerSession : public ShenandoahWorkerSession {
private:
  EventGCPhaseConcurrent _event;

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

class ShenandoahParallelWorkerSession : public ShenandoahWorkerSession {
private:
  EventGCPhaseParallel _event;

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

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

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

    _before_used_bytes += used;
    _regions_freed += 1;
  }

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

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

  public:
    JFREventForRegion(HeapRegion* region, uint worker_id) : _event() {
      _event.set_gcId(GCId::current());
      _event.set_gcWorkerId(worker_id);
      if (region->is_young()) {
        _event.set_name(G1GCPhaseTimes::phase_name(G1GCPhaseTimes::YoungFreeCSet));
      } else {
        _event.set_name(G1GCPhaseTimes::phase_name(G1GCPhaseTimes::NonYoungFreeCSet));
      }
    }

src/hotspot/share/gc/g1/g1GCParPhaseTimesTracker.hpp:

#ifndef SHARE_GC_G1_G1GCPARPHASETIMESTRACKER_HPP
#define SHARE_GC_G1_G1GCPARPHASETIMESTRACKER_HPP

#include "gc/g1/g1GCPhaseTimes.hpp"
#include "jfr/jfrEvents.hpp"
#include "utilities/ticks.hpp"

class G1GCParPhaseTimesTracker : public CHeapObj<mtGC> {
protected:
  Ticks _start_time;
  G1GCPhaseTimes::GCParPhases _phase;
  G1GCPhaseTimes* _phase_times;
  uint _worker_id;
  EventGCPhaseParallel _event;
  bool _allow_multiple_record;

public:
  G1GCParPhaseTimesTracker(G1GCPhaseTimes* phase_times, G1GCPhaseTimes::GCParPhases phase, uint worker_id, bool allow_multiple_record = false);
  virtual ~G1GCParPhaseTimesTracker();
};

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

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

    _scanned_to = scan_memregion(region_idx_for_card, mr);

    _cards_scanned += num_cards;
  }

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

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

    ResourceMark rm;

    G1CardTableChunkClaimer claim(_scan_state, region_idx);

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

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

  size_t _opt_roots_scanned;
  size_t _opt_refs_scanned;
  size_t _opt_refs_memory_used;

  Tickspan _strong_code_root_scan_time;
  Tickspan _strong_code_trim_partially_time;

  Tickspan _rem_set_opt_root_scan_time;
  Tickspan _rem_set_opt_trim_partially_time;

  void scan_opt_rem_set_roots(HeapRegion* r) {
    EventGCPhaseParallel event;

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

    G1ScanCardClosure scan_cl(G1CollectedHeap::heap(), _pss, _opt_roots_scanned);
    G1ScanRSForOptionalClosure cl(G1CollectedHeap::heap(), &scan_cl);
    _opt_refs_scanned += opt_rem_set_list->oops_do(&cl, _pss->closures()->strong_oops());
    _opt_refs_memory_used += opt_rem_set_list->used_memory();

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

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

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

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

    if (_scan_state->claim_collection_set_region(region_idx)) {
      EventGCPhaseParallel event;

      G1EvacPhaseWithTrimTimeTracker timer(_pss, _strong_code_root_scan_time, _strong_code_trim_partially_time);
      // Scan the strong code root list attached to the current region
      r->strong_code_roots_do(_pss->closures()->weak_codeblobs());

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

    return false;
  }

src/hotspot/share/gc/g1/g1YoungCollector.cpp:

  G1CollectedHeap*              _g1h;
  G1ParScanThreadState*         _par_scan_state;
  G1ScannerTasksQueueSet*       _queues;
  TaskTerminator*               _terminator;
  G1GCPhaseTimes::GCParPhases   _phase;

  G1ParScanThreadState*   par_scan_state() { return _par_scan_state; }
  G1ScannerTasksQueueSet* queues()         { return _queues; }
  TaskTerminator*         terminator()     { return _terminator; }

  inline bool offer_termination() {
    EventGCPhaseParallel event;
    G1ParScanThreadState* const pss = par_scan_state();
    start_term_time();
    const bool res = (terminator() == nullptr) ? true : terminator()->offer_termination();
    end_term_time();
    event.commit(GCId::current(), pss->worker_id(), G1GCPhaseTimes::phase_name(G1GCPhaseTimes::Termination));
    return res;
  }

public:
  G1ParEvacuateFollowersClosure(G1CollectedHeap* g1h,
                                G1ParScanThreadState* par_scan_state,
                                G1ScannerTasksQueueSet* queues,
                                TaskTerminator* terminator,
                                G1GCPhaseTimes::GCParPhases phase)
    : _start_term(0.0), _term_time(0.0), _term_attempts(0),
      _g1h(g1h), _par_scan_state(par_scan_state),
      _queues(queues), _terminator(terminator), _phase(phase) {}

  void do_void() {
    EventGCPhaseParallel event;
    G1ParScanThreadState* const pss = par_scan_state();
    pss->trim_queue();
    event.commit(GCId::current(), pss->worker_id(), G1GCPhaseTimes::phase_name(_phase));
    do {
      EventGCPhaseParallel event;
      pss->steal_and_trim_queue(queues());
      event.commit(GCId::current(), pss->worker_id(), G1GCPhaseTimes::phase_name(_phase));
    } while (!offer_termination());
  }

  double term_time() const { return _term_time; }
  size_t term_attempts() const { return _term_attempts; }
};

class G1EvacuateRegionsBaseTask : public WorkerTask {

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

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

Examples 3
gcId uint
2
gcWorkerId uint
0
name string
JNI Global
startTime long: millis
577624936
gcId uint
4
gcWorkerId uint
0
name string
UpdateDerivedPointers
startTime long: millis
1008184872
gcId uint
25
gcWorkerId uint
0
name string
Finish Mark
startTime long: millis
39492966577

JVM: GC: Reference

GCReferenceStatistics

default profiling startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Reference

Total count of processed references during GC

Code Context

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

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

  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;

Configuration enabled
default true
profiling true

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

Examples 3
count ulong
34
gcId uint
11
startTime long: millis
720352949
type ReferenceType
Weak reference
count ulong
0
gcId uint
14
startTime long: millis
1476874132
type ReferenceType
Final reference
count ulong
0
gcId uint
2
startTime long: millis
1333084861
type ReferenceType
Final reference

JVM: Internal

Duration

internal startTime duration eventThread 18 21 25 26 27

Category: Java Virtual Machine / Internal

Instant

internal startTime eventThread 18 21 25 26 27

Category: Java Virtual Machine / Internal

Code Context

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

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

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

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

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

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

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

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

        void setIsOsr(boolean isOsr);

        void setCodeSize(int codeSize);

        void setInlinedBytes(int inlinedBytes);
    }

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

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

        void setMessage(String message);
    }
}

Value

internal startTime eventThread 18 21 25 26 27

Category: Java Virtual Machine / Internal

Field Type Description
value ulong Value

Text

internal startTime eventThread 18 21 25 26 27

Category: Java Virtual Machine / Internal

Field Type Description
text string Text

JVM: Profiling

OldObjectSample

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

Category: Java Virtual Machine / Profiling

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ZGC

Missing in: linux_ShenandoahGC

A potential memory leak

Code Context

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

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

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

  const StoredEdge* const edge = edge_store->get(sample);
  assert(edge != NULL, "invariant");
  assert(edge->pointee() == sample->object(), "invariant");
  const traceid object_id = edge_store->get_id(edge);
  assert(object_id != 0, "invariant");
  const traceid gc_root_id = edge->gc_root_id();

  Tickspan object_age = Ticks(_start_time.value()) - sample->allocation_time();

  EventOldObjectSample e(UNTIMED);
  e.set_starttime(_start_time);
  e.set_endtime(_end_time);
  e.set_allocationTime(sample->allocation_time());
  e.set_objectSize(sample->allocated());
  e.set_objectAge(object_age);
  e.set_lastKnownHeapUsage(sample->heap_used_at_last_gc());
  e.set_object(object_id);
  e.set_arrayElements(array_size(edge->pointee()));
  e.set_root(gc_root_id);

  // Temporarily assigning both the stack trace id and thread id

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

  if (!tl->has_thread_blob()) {
    JfrCheckpointManager::create_thread_blob(thread);
  }
  assert(tl->has_thread_blob(), "invariant");
  return tl->thread_id();
}

class RecordStackTrace {
 private:
  JavaThread* _jt;
  bool _enabled;
 public:
  RecordStackTrace(JavaThread* jt) : _jt(jt),
    _enabled(JfrEventSetting::has_stacktrace(EventOldObjectSample::eventId)) {
    if (_enabled) {
      JfrStackTraceRepository::record_for_leak_profiler(jt);
    }
  }
  ~RecordStackTrace() {
    if (_enabled) {
      _jt->jfr_thread_local()->clear_cached_stack_trace();
    }
  }
};

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);

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

Field Type Description
allocationTime Ticks Allocation Time
objectSize ulong: bytes 18+ Object Size
objectAge Tickspan 14+ Object Age
lastKnownHeapUsage ulong: bytes Last Known Heap Usage
object OldObject Object
arrayElements int Array Elements If the object is an array, the number of elements, or -1 if it is not an array
root OldObjectGcRoot GC Root

Examples 3
allocationTime Ticks
34487343876
arrayElements int
-2147483648
lastKnownHeapUsage ulong: bytes
79818904
object OldObject
address ulong: address
30184347728
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/String
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
objectAge Tickspan
93388261389
objectSize ulong: bytes
24
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
39
lineNumber int
802
method Method
descriptor string
([BLjava/nio/charset/Charset;)Ljava/lang/String;
hidden boolean
false
modifiers int
10
name string
newStringNoRepl1
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/String
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
127875605265
allocationTime Ticks
47254146138
arrayElements int
-2147483648
lastKnownHeapUsage ulong: bytes
80595000
object OldObject
address ulong: address
30245886360
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/invoke/MethodType
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang/invoke
objectAge Tickspan
66095930001
objectSize ulong: bytes
32
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
11
lineNumber int
393
method Method
descriptor string
(Ljava/lang/Class;[Ljava/lang/Class;Z)Ljava/lang/invoke/MethodType;
hidden boolean
false
modifiers int
10
name string
makeImpl
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/invoke/MethodType
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang/invoke
type FrameType
Inlined
truncated boolean
true
startTime long: millis
113350076139
allocationTime Ticks
25399055860
arrayElements int
4096
lastKnownHeapUsage ulong: bytes
7765616
object OldObject
address ulong: address
30173450728
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
objectAge Tickspan
25535020
objectSize ulong: bytes
4112
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
24
lineNumber int
494
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
allocateAndGC
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
25424590880

ExecutionSample

default profiling startTime every chunk 11 17 21 25 26 27

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(static_cast<u8>(java_lang_Thread::get_thread_status(_thread_oop)));
    }
  }
}

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

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

bool JfrThreadSampleClosure::sample_thread_in_java(JavaThread* thread, JfrStackFrame* frames, u4 max_frames) {
  OSThreadSampler sampler(thread, *this, frames, max_frames);
  sampler.take_sample();
  /* We don't want to allocate any memory using malloc/etc while the thread
  * is stopped, so everything is stored in stack allocated memory until this
  * point where the thread has been resumed again, if the sampling was a success
  * we need to store the stacktrace in the stacktrace repository and update
  * the event with the id that was returned. */
  if (!sampler.success()) {
    return false;
  }
  EventExecutionSample *event = &_events[_added_java - 1];
  traceid id = JfrStackTraceRepository::add(sampler.stacktrace());
  assert(id != 0, "Stacktrace id should not be 0");
  event->set_stackTrace(id);
  return true;
}

bool JfrThreadSampleClosure::sample_thread_in_native(JavaThread* thread, JfrStackFrame* frames, u4 max_frames) {
  JfrNativeSamplerCallback cb(*this, thread, frames, max_frames);
  if (JfrOptionSet::sample_protection()) {
    os::ThreadCrashProtection crash_protection;
    if (!crash_protection.call(cb)) {

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

    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:

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

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

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

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

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

JVM_ENTRY_NO_ENV(void, jfr_subscribe_log_level(JNIEnv* env, jobject jvm, jobject log_tag, jint id))
  JfrJavaLog::subscribe_log_level(log_tag, id, thread);
JVM_END

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

JVM_ENTRY_NO_ENV(void, jfr_set_method_sampling_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

Configuration enabled period
default true 20 ms
profiling true 10 ms

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

Examples 3
sampledThread Thread
group ThreadGroup
name string
InnocuousForkJoinWorkerThreadGroup
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
ForkJoinPool.commonPool-worker-3
javaThreadId long
38
osName string
ForkJoinPool.commonPool-worker-3
osThreadId long
2809
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
122
lineNumber int
1856
method Method
descriptor string
(Ljava/util/function/Consumer;)V
hidden boolean
false
modifiers int
1
name string
forEachRemaining
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
24
name string
java/util/HashMap$EntrySpliterator
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
2261414572
state ThreadState
STATE_RUNNABLE
sampledThread Thread
group ThreadGroup
name string
InnocuousForkJoinWorkerThreadGroup
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
ForkJoinPool.commonPool-worker-3
javaThreadId long
34
osName string
ForkJoinPool.commonPool-worker-3
osThreadId long
2821
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
2
lineNumber int
125
method Method
descriptor string
(Ljava/util/function/Function;Ljava/lang/String;)Z
hidden boolean
false
modifiers int
4106
name string
lambda$run$8
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
25.0.3
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/renaissance/jdk/streams/JavaScrabble
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
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
org/renaissance/jdk/streams
type FrameType
Inlined
truncated boolean
false
startTime long: millis
2053139410
state ThreadState
STATE_RUNNABLE
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
3277
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
355
lineNumber int
193
method Method
descriptor string
([BI)V
hidden boolean
false
modifiers int
2
name string
implCompress0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1024
name string
sun/security/provider/SHA2
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
sun/security/provider
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
1115866340
state ThreadState
STATE_RUNNABLE

NativeMethodSample

default profiling startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Profiling

Snapshot of a threads state when in native

Code Context

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

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

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

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

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

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

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

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

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

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

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

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

bool JfrThreadSampleClosure::sample_thread_in_native(JavaThread* thread, JfrStackFrame* frames, u4 max_frames) {
  JfrNativeSamplerCallback cb(*this, thread, frames, max_frames);
  if (JfrOptionSet::sample_protection()) {
    os::ThreadCrashProtection crash_protection;
    if (!crash_protection.call(cb)) {
      log_error(jfr)("Thread method sampler crashed for native");
    }
  } else {
    cb.call();
  }
  if (!cb.success()) {
    return false;
  }
  EventNativeMethodSample *event = &_events_native[_added_native - 1];
  traceid id = JfrStackTraceRepository::add(cb.stacktrace());
  assert(id != 0, "Stacktrace id should not be 0");
  event->set_stackTrace(id);
  return true;
}

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

void JfrThreadSampleClosure::commit_events(JfrSampleType type) {
  if (JAVA_SAMPLE == type) {

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:

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

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

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

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

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

JVM_ENTRY_NO_ENV(void, jfr_subscribe_log_level(JNIEnv* env, jobject jvm, jobject log_tag, jint id))
  JfrJavaLog::subscribe_log_level(log_tag, id, thread);
JVM_END

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

JVM_ENTRY_NO_ENV(void, jfr_set_method_sampling_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))

Configuration enabled period
default true 20 ms
profiling true 20 ms

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

Examples 3
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
2793
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/io/FileDescriptor;JI)I
hidden boolean
false
modifiers int
264
name string
write0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
sun/nio/ch/UnixFileDispatcherImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
sun/nio/ch
type FrameType
Native
truncated boolean
false
startTime long: millis
4537644671
state ThreadState
STATE_RUNNABLE
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
2777
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/io/FileDescriptor;JI)I
hidden boolean
false
modifiers int
264
name string
write0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
sun/nio/ch/UnixFileDispatcherImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
sun/nio/ch
type FrameType
Native
truncated boolean
false
startTime long: millis
33691506826
state ThreadState
STATE_RUNNABLE
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
3277
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
25.0.3
name string
sun/nio/ch
type FrameType
Native
truncated boolean
false
startTime long: millis
21570625712
state ThreadState
STATE_RUNNABLE

JVM: Runtime

ReservedStackActivation

default profiling startTime eventThread stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime

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

Code Context

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

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

        for (ScopeDesc *sd = nm->scope_desc_near(fr.pc()); sd != NULL; sd = sd->sender()) {
          method = sd->method();
          if (method != NULL && method->has_reserved_stack_access()) {
            found = true;
      }
    }
      }
    }
    if (found) {
      activation = fr;
      warning("Potentially dangerous stack overflow in "
              "ReservedStackAccess annotated method %s [%d]",
              method->name_and_sig_as_C_string(), count++);
      EventReservedStackActivation event;
      if (event.should_commit()) {
        event.set_method(method);
        event.commit();
      }
    }
    if (fr.is_first_java_frame()) {
      break;
    } else {
      fr = fr.java_sender();
    }
  }

Configuration enabled stackTrace
default true true
profiling true true

Field Type Description
method Method Java Method

SafepointBegin

default profiling startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime / Safepoint

Safepointing begin

Code Context

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

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

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

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

  OrderAccess::storestore(); // storestore, global state -> local state
  for (JavaThreadIteratorWithHandle jtiwh; JavaThread *cur = jtiwh.next(); ) {
    // Make sure the threads start polling, it is time to yield.
    SafepointMechanism::arm_local_poll(cur);
  }

  OrderAccess::fence(); // storestore|storeload, global state -> local state
}

// Roll all threads forward to a safepoint and suspend them all
void SafepointSynchronize::begin() {
  assert(Thread::current()->is_VM_thread(), "Only VM thread may execute a safepoint");

  EventSafepointBegin begin_event;
  SafepointTracing::begin(VMThread::vm_op_type());

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

  // By getting the Threads_lock, we assure that no threads are about to start or
  // exit. It is released again in SafepointSynchronize::end().
  Threads_lock->lock();

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

  int nof_threads = Threads::number_of_threads();

Configuration enabled threshold
default true 10 ms
profiling true 0 ms

Field Type Description
safepointId ulong Safepoint Identifier
totalThreadCount int Total Threads The total number of threads at the start of safe point
jniCriticalThreadCount int JNI Critical Threads The number of threads in JNI critical sections

Examples 3
jniCriticalThreadCount int
0
safepointId ulong
57
startTime long: millis
28084052470
totalThreadCount int
26
jniCriticalThreadCount int
0
safepointId ulong
59
startTime long: millis
5522385109
totalThreadCount int
21
jniCriticalThreadCount int
0
safepointId ulong
3
startTime long: millis
368203890
totalThreadCount int
12

SafepointStateSynchronization

startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime / Safepoint

Synchronize run state of threads

Code Context

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

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

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

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

static void post_safepoint_synchronize_event(EventSafepointStateSynchronization& event,
                                             uint64_t safepoint_id,
                                             int initial_number_of_threads,
                                             int threads_waiting_to_block,
                                             uint64_t iterations) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.set_initialThreadCount(initial_number_of_threads);
    event.set_runningThreadCount(threads_waiting_to_block);
    event.set_iterations(iterations);
    event.commit();
  }

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

  _current_jni_active_count = 0;

  // Set number of threads to wait for
  _waiting_to_block = nof_threads;

  jlong safepoint_limit_time = 0;
  if (SafepointTimeout) {
    // Set the limit time, so that it can be compared to see if this has taken
    // too long to complete.
    safepoint_limit_time = SafepointTracing::start_of_safepoint() + (jlong)SafepointTimeoutDelay * (NANOUNITS / MILLIUNITS);
    timeout_error_printed = false;
  }

  EventSafepointStateSynchronization sync_event;
  int initial_running = 0;

  // Arms the safepoint, _current_jni_active_count and _waiting_to_block must be set before.
  arm_safepoint();

  // Will spin until all threads are safe.
  int iterations = synchronize_threads(safepoint_limit_time, nof_threads, &initial_running);
  assert(_waiting_to_block == 0, "No thread should be running");

#ifndef PRODUCT
  // Mark all threads

Configuration enabled threshold
default false 10 ms
profiling false 0 ms

Field Type Description
safepointId ulong Safepoint Identifier
initialThreadCount int Initial Threads The number of threads running at the beginning of state check
runningThreadCount int Running Threads The number of threads still running
iterations int Iterations Number of state check iterations

Examples 3
initialThreadCount int
7
iterations int
3
runningThreadCount int
0
safepointId ulong
27
startTime long: millis
10582454793
initialThreadCount int
7
iterations int
3
runningThreadCount int
0
safepointId ulong
36
startTime long: millis
1466507852
initialThreadCount int
2
iterations int
3
runningThreadCount int
0
safepointId ulong
57
startTime long: millis
5439599583

SafepointCleanup

startTime duration eventThread 11 17 21 until JDK 23

Category: Java Virtual Machine / Runtime / Safepoint

Safepointing begin running cleanup tasks

Code Context

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

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

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

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

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

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

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

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

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

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

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

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

Configuration enabled threshold
default false 10 ms
profiling false 0 ms

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:

class ParallelSPCleanupTask : public WorkerTask {
private:
  SubTasksDone _subtasks;
  uint _num_workers;
  bool _do_lazy_roots;

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

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

Configuration enabled threshold
default false 10 ms
profiling false 0 ms

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

SafepointEnd

startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime / Safepoint

Safepointing end

Code Context

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

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

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

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

// SafepointCheck
SafepointStateTracker::SafepointStateTracker(uint64_t safepoint_id, bool at_safepoint)
  : _safepoint_id(safepoint_id), _at_safepoint(at_safepoint) {}

bool SafepointStateTracker::safepoint_state_changed() {

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

  } // ~JavaThreadIteratorWithHandle

  // Release threads lock, so threads can be created/destroyed again.
  Threads_lock->unlock();

  // Wake threads after local state is correctly set.
  _wait_barrier->disarm();
}

// Wake up all threads, so they are ready to resume execution after the safepoint
// operation has been carried out
void SafepointSynchronize::end() {
  assert(Threads_lock->owned_by_self(), "must hold Threads_lock");
  EventSafepointEnd event;
  assert(Thread::current()->is_VM_thread(), "Only VM thread can execute a safepoint");

  disarm_safepoint();

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

  SafepointTracing::end();

  post_safepoint_end_event(event, safepoint_id());
}

Configuration enabled threshold
default false 10 ms
profiling false 0 ms

Field Type Description
safepointId ulong Safepoint Identifier

Examples 3
safepointId ulong
72
startTime long: millis
38293252795
safepointId ulong
91
startTime long: millis
2247887270
safepointId ulong
83
startTime long: millis
7240882124

ExecuteVMOperation

default profiling startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime

Execution of a VM Operation

Code Context

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

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

  // Wait until VM thread is terminated
  // Note: it should be OK to use Terminator_lock here. But this is called
  // at a very delicate time (VM shutdown) and we are operating in non- VM
  // thread at Safepoint. It's safer to not share lock with other threads.
  {
    MonitorLocker ml(_terminate_lock, Mutex::_no_safepoint_check_flag);
    while (!VMThread::is_terminated()) {
      ml.wait();
    }
  }
}

static void post_vm_operation_event(EventExecuteVMOperation* event, VM_Operation* op) {
  assert(event != NULL, "invariant");
  assert(event->should_commit(), "invariant");
  assert(op != NULL, "invariant");
  const bool evaluate_at_safepoint = op->evaluate_at_safepoint();
  event->set_operation(op->type());
  event->set_safepoint(evaluate_at_safepoint);
  event->set_blocking(true);
  event->set_caller(JFR_THREAD_ID(op->calling_thread()));
  event->set_safepointId(evaluate_at_safepoint ? SafepointSynchronize::safepoint_id() : 0);
  event->commit();
}

void VMThread::evaluate_operation(VM_Operation* op) {
  ResourceMark rm;

  {
    PerfTraceTime vm_op_timer(perf_accumulated_vm_operation_time());
    HOTSPOT_VMOPS_BEGIN(
                     (char *) op->name(), strlen(op->name()),
                     op->evaluate_at_safepoint() ? 0 : 1);

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

    HOTSPOT_VMOPS_END(
                     (char *) op->name(), strlen(op->name()),
                     op->evaluate_at_safepoint() ? 0 : 1);
  }

}

Configuration enabled threshold
default true 10 ms
profiling true 0 ms

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
blocking boolean
true
caller Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
pool-1-thread-2
javaThreadId long
35
osName string
pool-1-thread-2
osThreadId long
3308
virtual boolean
false
operation VMOperationType
G1CollectForAllocation
safepoint boolean
true
safepointId ulong
66
startTime long: millis
1919239522
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
2793
virtual boolean
false
operation VMOperationType
CollectForMetadataAllocation
safepoint boolean
true
safepointId ulong
18
startTime long: millis
3937795487
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
2777
virtual boolean
false
operation VMOperationType
CollectForMetadataAllocation
safepoint boolean
true
safepointId ulong
45
startTime long: millis
4499943743

Shutdown

default profiling startTime eventThread stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime

JVM shutting down

Code Context

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

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

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

extern volatile jint vm_created;

JVM_ENTRY_NO_ENV(void, JVM_BeforeHalt())
#if INCLUDE_CDS
  // Link all classes for dynamic CDS dumping before vm exit.
  if (DynamicArchive::should_dump_at_vm_exit()) {
    DynamicArchive::prepare_for_dump_at_exit();
  }
#endif
  EventShutdown event;
  if (event.should_commit()) {
    event.set_reason("Shutdown requested from Java");
    event.commit();
  }
JVM_END


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

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

  JavaThread* thread = JavaThread::current();

#ifdef ASSERT
  _vm_complete = false;
#endif
  // Wait until we are the last non-daemon thread to execute
  {
    MonitorLocker nu(Threads_lock);
    while (Threads::number_of_non_daemon_threads() > 1)
      // This wait should make safepoint checks, wait without a timeout.
      nu.wait(0);
  }

  EventShutdown e;
  if (e.should_commit()) {
    e.set_reason("No remaining non-daemon Java threads");
    e.commit();
  }

  // Hang forever on exit if we are reporting an error.
  if (ShowMessageBoxOnError && VMError::is_error_reported()) {
    os::infinite_sleep();
  }
  os::wait_for_keypress_at_exit();

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

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

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

Configuration enabled stackTrace
default true true
profiling true true

Field Type Description
reason string Reason Reason for JVM shutdown

Examples 3
reason string
No remaining non-daemon Java threads
stackTrace StackTrace
null
startTime long: millis
25424037364
reason string
Shutdown requested from Java
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
264
name string
beforeHalt
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/Shutdown
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
127875037324
reason string
Shutdown requested from Java
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
264
name string
beforeHalt
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/Shutdown
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
113349532882

SymbolTableStatistics

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

Category: Java Virtual Machine / Runtime / Tables

Code Context

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

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

  event.set_entryCount(statistics._number_of_entries);
  event.set_totalFootprint(statistics._total_footprint);
  event.set_bucketCountMaximum(statistics._maximum_bucket_size);
  event.set_bucketCountAverage(statistics._average_bucket_size);
  event.set_bucketCountVariance(statistics._variance_of_bucket_size);
  event.set_bucketCountStandardDeviation(statistics._stddev_of_bucket_size);
  event.set_insertionRate(statistics._add_rate);
  event.set_removalRate(statistics._remove_rate);
  event.commit();
}

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

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

TRACE_REQUEST_FUNC(PlaceholderTableStatistics) {
  TableStatistics statistics = SystemDictionary::placeholders_statistics();
  emit_table_statistics<EventPlaceholderTableStatistics>(statistics);
}

Configuration enabled period
default true 10 s
profiling true 10 s

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

Examples 3
bucketCount ulong
32768
bucketCountAverage float
1.1361694
bucketCountMaximum ulong
7
bucketCountStandardDeviation float
1.0580157
bucketCountVariance float
1.1193973
entryCount ulong
37230
insertionRate float
33177.0
removalRate float
2350.0
startTime long: millis
10624956335
totalFootprint ulong: bytes
2449464
bucketCount ulong
32768
bucketCountAverage float
2.5447083
bucketCountMaximum ulong
11
bucketCountStandardDeviation float
1.594578
bucketCountVariance float
2.5426788
entryCount ulong
83385
insertionRate float
80167.0
removalRate float
3177.0
startTime long: millis
10530757040
totalFootprint ulong: bytes
6631224
bucketCount ulong
32768
bucketCountAverage float
2.5820923
bucketCountMaximum ulong
11
bucketCountStandardDeviation float
1.6056082
bucketCountVariance float
2.5779777
entryCount ulong
84610
insertionRate float
282.9273
removalRate float
173.00261
startTime long: millis
31937023465
totalFootprint ulong: bytes
6735744

StringTableStatistics

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

Category: Java Virtual Machine / Runtime / Tables

Code Context

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

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

  event.set_bucketCountStandardDeviation(statistics._stddev_of_bucket_size);
  event.set_insertionRate(statistics._add_rate);
  event.set_removalRate(statistics._remove_rate);
  event.commit();
}

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

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

TRACE_REQUEST_FUNC(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);
}

Configuration enabled period
default true 10 s
profiling true 10 s

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

Examples 3
bucketCount ulong
65536
bucketCountAverage float
0.09602356
bucketCountMaximum ulong
3
bucketCountStandardDeviation float
0.31060764
bucketCountVariance float
0.096477106
entryCount ulong
6293
insertionRate float
5507.0
removalRate float
28.0
startTime long: millis
10626531440
totalFootprint ulong: bytes
1033512
bucketCount ulong
65536
bucketCountAverage float
0.58213806
bucketCountMaximum ulong
6
bucketCountStandardDeviation float
0.7583947
bucketCountVariance float
0.57516253
entryCount ulong
38151
insertionRate float
792.99817
removalRate float
15.150341
startTime long: millis
62445043638
totalFootprint ulong: bytes
4330688
bucketCount ulong
65536
bucketCountAverage float
0.74790955
bucketCountMaximum ulong
7
bucketCountStandardDeviation float
0.8618591
bucketCountVariance float
0.74280113
entryCount ulong
49015
insertionRate float
211.4629
removalRate float
41.896263
startTime long: millis
82458513806
totalFootprint ulong: bytes
5351136

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);
}

Configuration enabled period
default true 10 s
profiling true 10 s

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

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());

Configuration enabled period
default true 10 s
profiling true 10 s

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());

Configuration enabled period
default true 10 s
profiling true 10 s

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

ThreadDump

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

Category: Java Virtual Machine / Runtime

Code Context

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

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

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

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

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

/*
 * This is left empty on purpose, having ExecutionSample as a requestable
 * is a way of getting the period. The period is passed to ThreadSampling::update_period.
 * Implementation in jfrSamples.cpp
 */
TRACE_REQUEST_FUNC(ExecutionSample) {
}
TRACE_REQUEST_FUNC(NativeMethodSample) {
}

TRACE_REQUEST_FUNC(ThreadDump) {
  ResourceMark rm;
  EventThreadDump event;
  event.set_result(JfrDcmdEvent::thread_dump());
  event.commit();
}

static int _native_library_callback(const char* name, address base, address top, void *param) {
  EventNativeLibrary event(UNTIMED);
  event.set_name(name);
  event.set_baseAddress((u8)base);
  event.set_topAddress((u8)top);
  event.set_endtime(*(JfrTicks*) param);
  event.commit();

Configuration enabled period
default true everyChunk
profiling true 60 s

Field Type Description
result string Thread Dump

Examples 3
result string
2026-06-03 14:07:33 Full thread dump OpenJDK 64-Bit Server VM (25.0.3+9-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x00007fb28a938730, length=46, elements={ 0x00007fb2b0053b20, 0x00007fb2b00ca340, 0x00007fb2b00cbf30, 0x00007fb2b00cdf70, 0x00007fb2b00cfd80, 0x00007fb2b00d15d
startTime long: millis
92618289682
result string
2026-06-03 14:08:44 Full thread dump OpenJDK 64-Bit Server VM (25.0.3+9-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x00007f757db92680, length=25, elements={ 0x00007f757c055840, 0x00007f757c1548e0, 0x00007f757c1567a0, 0x00007f757c158c10, 0x00007f757c15ab50, 0x00007f757c15c6e
startTime long: millis
20836148642
result string
2026-06-03 14:08:08 Full thread dump OpenJDK 64-Bit Server VM (25.0.3+9-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x0000557dd8f435a0, length=48, elements={ 0x00007ff2e8053b40, 0x00007ff2e8141af0, 0x00007ff2e8143840, 0x00007ff2e8145780, 0x00007ff2e8147490, 0x00007ff2e8148e4
startTime long: millis
114177338533

NativeLibrary

default profiling startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime

Code Context

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

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

TRACE_REQUEST_FUNC(ExecutionSample) {
}
TRACE_REQUEST_FUNC(NativeMethodSample) {
}

TRACE_REQUEST_FUNC(ThreadDump) {
  ResourceMark rm;
  EventThreadDump event;
  event.set_result(JfrDcmdEvent::thread_dump());
  event.commit();
}

static int _native_library_callback(const char* name, address base, address top, void *param) {
  EventNativeLibrary event(UNTIMED);
  event.set_name(name);
  event.set_baseAddress((u8)base);
  event.set_topAddress((u8)top);
  event.set_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);

Configuration enabled period
default true everyChunk
profiling true everyChunk

Field Type Description
name string Name
baseAddress ulong: address Base Address Starting address of the module
topAddress ulong: address Top Address Ending address of the module

Examples 3
baseAddress ulong: address
140405580947456
name string
linux-vdso.so.1
startTime long: millis
16948114888
topAddress ulong: address
140405580955648
baseAddress ulong: address
140681343401984
name string
/opt/hostedtoolcache/Java_SapMachine_jdk/25.0.3/x64/lib/server/libjvm.so
startTime long: millis
8901549165
topAddress ulong: address
140681368375296
baseAddress ulong: address
140142683570176
name string
/opt/hostedtoolcache/Java_SapMachine_jdk/25.0.3/x64/lib/libjava.so
startTime long: millis
373457001
topAddress ulong: address
140142683713536

ModuleRequire

default profiling startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime / Modules

A directed edge representing a dependency

Code Context

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

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

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

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

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

Configuration enabled period
default true endChunk
profiling true endChunk

Field Type Description
source Module Source Module
requiredModule Module Required Module

Examples 3
requiredModule Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
location string
jrt:/jdk.jdi
name string
jdk.jdi
version string
25.0.3
startTime long: millis
8580978333
requiredModule Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
source Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
name string
jdk/internal/loader
location string
jrt:/jdk.jartool
name string
jdk.jartool
version string
25.0.3
startTime long: millis
8156486581
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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
location string
jrt:/jdk.internal.opt
name string
jdk.internal.opt
version string
25.0.3
source Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
name string
jdk/internal/loader
location string
jrt:/jdk.compiler
name string
jdk.compiler
version string
25.0.3
startTime long: millis
8901564364

ModuleExport

default profiling startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime / Modules

Code Context

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

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

  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");

Configuration enabled period
default true endChunk
profiling true endChunk

Field Type Description
exportedPackage Package Exported Package
targetModule Module Target Module Module to which the package is qualifiedly exported. If null or N/A, the package is unqualifiedly exported

Examples 3
exportedPackage Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.desktop
name string
java.desktop
version string
25.0.3
name string
java/awt/geom
startTime long: millis
8156530253
targetModule Module
null
exportedPackage Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.naming
name string
java.naming
version string
25.0.3
name string
javax/naming/event
startTime long: millis
8581054869
targetModule Module
null
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
25.0.3
name string
java/net
startTime long: millis
8901612804
targetModule Module
null

Java Application

ThreadStart

default profiling startTime eventThread stackTrace 11 17 21 25 26 27

Category: Java Application

Code Context

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

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

                            JavaThread::name_for(JNIHandles::resolve_non_null(jthread)));
    // No one should hold a reference to the 'native_thread'.
    native_thread->smr_delete();
    if (JvmtiExport::should_post_resource_exhausted()) {
      JvmtiExport::post_resource_exhausted(
        JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR | JVMTI_RESOURCE_EXHAUSTED_THREADS,
        os::native_thread_creation_failed_msg());
    }
    THROW_MSG(vmSymbols::java_lang_OutOfMemoryError(),
              os::native_thread_creation_failed_msg());
  }

#if INCLUDE_JFR
  if (Jfr::is_recording() && EventThreadStart::is_enabled() &&
      EventThreadStart::is_stacktrace_enabled()) {
    JfrThreadLocal* tl = native_thread->jfr_thread_local();
    // skip Thread.start() and Thread.start0()
    tl->set_cached_stack_trace_id(JfrStackTraceRepository::record(thread, 2));
  }
#endif

  Thread::start(native_thread);

JVM_END

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

void JfrThreadLocal::set_thread_blob(const JfrBlobHandle& ref) {
  assert(!_thread.valid(), "invariant");
  _thread = ref;
}

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

static void send_java_thread_start_event(JavaThread* jt) {
  EventThreadStart event;
  event.set_thread(jt->jfr_thread_local()->thread_id());
  event.set_parentThread(jt->jfr_thread_local()->parent_thread_id());
  event.commit();
}

void JfrThreadLocal::on_start(Thread* t) {
  assert(t != NULL, "invariant");
  assert(Thread::current() == t, "invariant");
  JfrJavaSupport::on_thread_start(t);
  if (JfrRecorder::is_recording()) {
    JfrCheckpointManager::write_thread_checkpoint(t);

Configuration enabled stackTrace
default true true
profiling true true

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

Examples 3
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
3
osName string
main
osThreadId long
2793
virtual boolean
false
stackTrace StackTrace
null
startTime long: millis
379710668
thread Thread
group ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Notification Thread
javaThreadId long
27
osName string
Notification Thread
osThreadId long
2817
virtual boolean
false
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
3277
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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
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
4844673892
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Thread-71
javaThreadId long
128
osName string
Thread-71
osThreadId long
3411
virtual boolean
false
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-6
javaThreadId long
115
osName string
UCT-akka.actor.default-dispatcher-6
osThreadId long
2889
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
2
lineNumber int
2231
method Method
descriptor string
(Ljava/lang/Thread;Ljdk/internal/vm/ThreadContainer;)V
hidden boolean
false
modifiers int
1
name string
start
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/System$1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
14807511879
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-10
javaThreadId long
119
osName string
UCT-akka.actor.default-dispatcher-10
osThreadId long
2893
virtual boolean
false

ThreadEnd

default profiling startTime eventThread 11 17 21 25 26 27

Category: Java Application

Code Context

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

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

#if INCLUDE_JVMCI
  if (EnableJVMCI) {
    JVMCI::shutdown();
  }
#endif

  // Hang forever on exit if we're reporting an error.
  if (ShowMessageBoxOnError && VMError::is_error_reported()) {
    os::infinite_sleep();
  }

  EventThreadEnd event;
  if (event.should_commit()) {
    event.set_thread(JFR_THREAD_ID(thread));
    event.commit();
  }

  JFR_ONLY(Jfr::on_vm_shutdown();)

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

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

  if (t->jfr_thread_local()->has_cached_stack_trace()) {
    t->jfr_thread_local()->clear_cached_stack_trace();
  }
}

static void send_java_thread_end_events(traceid id, JavaThread* jt) {
  assert(jt != NULL, "invariant");
  assert(Thread::current() == jt, "invariant");
  assert(jt->jfr_thread_local()->trace_id() == id, "invariant");
  if (JfrRecorder::is_recording()) {
    EventThreadEnd event;
    event.set_thread(id);
    event.commit();
    JfrThreadCPULoadEvent::send_event_for_thread(jt);
  }
}

void JfrThreadLocal::release(Thread* t) {
  if (has_java_event_writer()) {
    assert(t->is_Java_thread(), "invariant");
    JfrJavaSupport::destroy_global_jni_handle(java_event_writer());
    _java_event_writer = NULL;

Configuration enabled
default true
profiling true

Field Type Description
thread Thread Java Thread

Examples 3
startTime long: millis
16151891746
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-13
javaThreadId long
129
osName string
UCT-akka.actor.default-dispatcher-13
osThreadId long
2919
virtual boolean
false
startTime long: millis
14814827413
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-13
javaThreadId long
93
osName string
UCT-akka.actor.default-dispatcher-13
osThreadId long
2868
virtual boolean
false
startTime long: millis
3842386113
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Thread-49
javaThreadId long
106
osName string
Thread-49
osThreadId long
3389
virtual boolean
false

ThreadSleep

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

Category: Java Application

Code Context

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

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

  // Implied else: If the JavaThread hasn't started yet, then the
  // priority set in the java.lang.Thread object above will be pushed
  // down when it does start.
JVM_END


JVM_ENTRY(void, JVM_Yield(JNIEnv *env, jclass threadClass))
  if (os::dont_yield()) return;
  HOTSPOT_THREAD_YIELD();
  os::naked_yield();
JVM_END

static void post_thread_sleep_event(EventThreadSleep* event, jlong millis) {
  assert(event != NULL, "invariant");
  assert(event->should_commit(), "invariant");
  event->set_time(millis);
  event->commit();
}

JVM_ENTRY(void, JVM_Sleep(JNIEnv* env, jclass threadClass, jlong millis))
  if (millis < 0) {
    THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "timeout value is negative");
  }

  if (thread->is_interrupted(true) && !HAS_PENDING_EXCEPTION) {
    THROW_MSG(vmSymbols::java_lang_InterruptedException(), "sleep interrupted");
  }

  // Save current thread state and restore it at the end of this block.
  // And set new thread state to SLEEPING.
  JavaThreadSleepState jtss(thread);

  HOTSPOT_THREAD_SLEEP_BEGIN(millis);
  EventThreadSleep event;

  if (millis == 0) {
    os::naked_yield();
  } else {
    ThreadState old_state = thread->osthread()->get_state();
    thread->osthread()->set_state(SLEEPING);
    if (!thread->sleep(millis)) { // interrupted
      // An asynchronous exception (e.g., ThreadDeathException) could have been thrown on
      // us while we were sleeping. We do not overwrite those.
      if (!HAS_PENDING_EXCEPTION) {
        if (event.should_commit()) {

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

Field Type Description
time long: millis Sleep Time

Examples 3
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
36
lineNumber int
90
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
1
name string
waitNanos
type Class
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null
type Class
classLoader ClassLoader
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bootstrap
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null
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1
name string
java/net/URLClassLoader
package Package
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bootstrap
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null
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jrt:/java.base
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java.base
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25.0.3
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java/net
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akka/actor/LightArrayRevolverScheduler
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module Module
classLoader ClassLoader
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null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
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modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
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module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/net
location string
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name string
null
version string
null
name string
akka/actor
type FrameType
Interpreted
truncated boolean
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startTime long: millis
8506770447
time long: millis
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stackTrace StackTrace
frames StackFrame
bytecodeIndex int
36
lineNumber int
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method Method
descriptor string
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akka/actor/LightArrayRevolverScheduler
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module Module
classLoader ClassLoader
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null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
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bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/net
location string
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name string
null
version string
null
name string
akka/actor
type FrameType
Interpreted
truncated boolean
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startTime long: millis
8252165934
time long: millis
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stackTrace StackTrace
frames StackFrame
bytecodeIndex int
9
lineNumber int
402
method Method
descriptor string
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4106
name string
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type Class
classLoader ClassLoader
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classLoader ClassLoader
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bootstrap
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10
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jdk/internal/loader/ClassLoaders$AppClassLoader
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null
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jfr_sample
type FrameType
Interpreted
truncated boolean
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startTime long: millis
617512347
time long: millis
5000000

ThreadPark

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

Category: Java Application

Code Context

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

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

UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
  oop p = JNIHandles::resolve(obj);
  volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
  return Atomic::cmpxchg(addr, e, x) == e;
} UNSAFE_END

UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
  oop p = JNIHandles::resolve(obj);
  volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
  return Atomic::cmpxchg(addr, e, x) == e;
} UNSAFE_END

static void post_thread_park_event(EventThreadPark* event, const oop obj, jlong timeout_nanos, jlong until_epoch_millis) {
  assert(event != NULL, "invariant");
  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 {

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

Field Type Description
parkedClass Class Class Parked On
timeout long: nanos Park Timeout
until long: epochmillis Park Until
address ulong: address Address of Object Parked

Examples 3
address ulong: address
30173225136
parkedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/ForkJoinPool
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util/concurrent
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
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location string
jrt:/java.base
name string
java.base
version string
25.0.3
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jdk/internal/misc
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startTime long: millis
4676543550
timeout long: nanos
-9223372036854775808
until long: epochmillis
-9223372036854775808
address ulong: address
0
parkedClass Class
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
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(ZJ)V
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257
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park
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17
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jdk/internal/misc/Unsafe
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3361912065
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-9223372036854775808
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30174311368
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1
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java/util/concurrent/ForkJoinPool
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jrt:/java.base
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java.base
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25.0.3
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method Method
descriptor string
(ZJ)V
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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
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true
module Module
classLoader ClassLoader
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bootstrap
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null
location string
jrt:/java.base
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java.base
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25.0.3
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jdk/internal/misc
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false
startTime long: millis
5267446982
timeout long: nanos
-9223372036854775808
until long: epochmillis
-9223372036854775808

JavaMonitorEnter

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

Category: Java Application

Code Context

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

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

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

  JFR_ONLY(JfrConditionalFlushWithStacktrace<EventJavaMonitorEnter> flush(current);)
  EventJavaMonitorEnter event;
  if (event.is_started()) {
    event.set_monitorClass(object()->klass());
    // Set an address that is 'unique enough', such that events close in
    // time and with the same address are likely (but not guaranteed) to
    // belong to the same object.
    event.set_address((uintptr_t)this);
  }

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

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

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

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

#if INCLUDE_JFR
  // get the owner's thread id for the MonitorEnter event
  // if it is enabled and the thread isn't suspended
  if (not_suspended && EventJavaMonitorEnter::is_enabled()) {
    _previous_owner_tid = JFR_THREAD_ID(current);
  }
#endif

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

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

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

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

Examples 3
address ulong: address
93998975694400
monitorClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
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java/net/URLClassLoader
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exported boolean
true
module Module
classLoader ClassLoader
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bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
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25.0.3
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java/net
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modifiers int
25
name string
edu/rice/habanero/actors/AkkaActorState$actorLatch$
package Package
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true
module Module
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null
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classLoader ClassLoader
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null
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1
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java/net/URLClassLoader
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java.base
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25.0.3
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null
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edu/rice/habanero/actors
previousOwner Thread
group ThreadGroup
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main
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system
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javaName string
UCT-akka.actor.default-dispatcher-8
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56
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UCT-akka.actor.default-dispatcher-8
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2833
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4
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java/net
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edu/rice/habanero/actors/AkkaActorState$actorLatch$
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java/net/URLClassLoader
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java.base
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25.0.3
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java/net
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null
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null
name string
edu/rice/habanero/actors
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Interpreted
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false
startTime long: millis
8764432580
address ulong: address
140405474002880
monitorClass Class
classLoader ClassLoader
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null
type Class
classLoader ClassLoader
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bootstrap
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null
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false
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1
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java/net/URLClassLoader
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null
location string
jrt:/java.base
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java.base
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25.0.3
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java/net
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25
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edu/rice/habanero/actors/AkkaActorState$actorLatch$
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true
module Module
classLoader ClassLoader
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null
type Class
classLoader ClassLoader
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bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
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true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
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jrt:/java.base
name string
java.base
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25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
edu/rice/habanero/actors
previousOwner Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-10
javaThreadId long
53
osName string
UCT-akka.actor.default-dispatcher-10
osThreadId long
2848
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
3
lineNumber int
114
method Method
descriptor string
()V
hidden boolean
false
modifiers int
1
name string
countUp
type Class
classLoader ClassLoader
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null
type Class
classLoader ClassLoader
name string
bootstrap
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null
hidden boolean
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modifiers int
1
name string
java/net/URLClassLoader
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module Module
classLoader ClassLoader
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bootstrap
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null
location string
jrt:/java.base
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java.base
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25.0.3
name string
java/net
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25
name string
edu/rice/habanero/actors/AkkaActorState$actorLatch$
package Package
exported boolean
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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
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bootstrap
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null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
edu/rice/habanero/actors
type FrameType
Inlined
truncated boolean
false
startTime long: millis
8229626013
address ulong: address
140142571110320
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
25.0.3
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
3277
virtual boolean
false
stackTrace StackTrace
null
startTime long: millis
8182598339

JavaMonitorWait

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

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:

  void* cur = owner_raw();
  if (cur == current) {
    return true;
  }
  if (current->is_lock_owned((address)cur)) {
    set_owner_from_BasicLock(cur, current);  // Convert from BasicLock* to Thread*.
    _recursions = 0;
    return true;
  }
  THROW_MSG_(vmSymbols::java_lang_IllegalMonitorStateException(),
             "current thread is not owner", false);
}

static void post_monitor_wait_event(EventJavaMonitorWait* event,
                                    ObjectMonitor* monitor,
                                    uint64_t notifier_tid,
                                    jlong timeout,
                                    bool timedout) {
  assert(event != NULL, "invariant");
  assert(monitor != NULL, "invariant");
  event->set_monitorClass(monitor->object()->klass());
  event->set_timeout(timeout);
  // Set an address that is 'unique enough', such that events close in
  // time and with the same address are likely (but not guaranteed) to
  // belong to the same object.

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

// -----------------------------------------------------------------------------
// Wait/Notify/NotifyAll
//
// Note: a subset of changes to ObjectMonitor::wait()
// will need to be replicated in complete_exit
void ObjectMonitor::wait(jlong millis, bool interruptible, TRAPS) {
  JavaThread* current = THREAD;

  assert(InitDone, "Unexpectedly not initialized");

  CHECK_OWNER();  // Throws IMSE if not owner.

  EventJavaMonitorWait event;

  // check for a pending interrupt
  if (interruptible && current->is_interrupted(true) && !HAS_PENDING_EXCEPTION) {
    // post monitor waited event.  Note that this is past-tense, we are done waiting.
    if (JvmtiExport::should_post_monitor_waited()) {
      // Note: 'false' parameter is passed here because the
      // wait was not timed out due to thread interrupt.
      JvmtiExport::post_monitor_waited(current, this, false);

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

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

Field Type Description
monitorClass Class Monitor Class Class of object waited on
notifier Thread Notifier Thread Notifying Thread
timeout long: millis Timeout Maximum wait time
timedOut boolean Timed Out Wait has been timed out
address ulong: address Monitor Address Address of object waited on

Examples 3
address ulong: address
140142602387312
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
25.0.3
name string
java/lang
notifier Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Thread-31
javaThreadId long
88
osName string
Thread-31
osThreadId long
3371
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
274
name string
wait0
type Class
classLoader ClassLoader
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bootstrap
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null
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false
modifiers int
1
name string
java/lang/Object
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true
module Module
classLoader ClassLoader
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bootstrap
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null
location string
jrt:/java.base
name string
java.base
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25.0.3
name string
java/lang
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Native
truncated boolean
false
startTime long: millis
2989499686
timedOut boolean
false
timeout long: millis
500
address ulong: address
93878653343008
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[I
package Package
null
notifier Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Thread-17
javaThreadId long
240
osName string
Thread-17
osThreadId long
3054
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
20
lineNumber int
686
method Method
descriptor string
(Lorg/neo4j/cypher/internal/expressions/Pattern$SemanticContext;Lscala/Option;)Lorg/neo4j/cypher/internal/ast/semantics/SemanticCheck;
hidden boolean
false
modifiers int
2
name string
checkNodeProperties
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/net
hidden boolean
false
modifiers int
17
name string
org/neo4j/cypher/internal/ast/semantics/SemanticPatternCheck$
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
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
org/neo4j/cypher/internal/ast/semantics
type FrameType
Interpreted
truncated boolean
true
startTime long: millis
47273533204
timedOut boolean
false
timeout long: millis
0
address ulong: address
140681284603632
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[I
package Package
null
notifier Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Thread-17
javaThreadId long
251
osName string
Thread-17
osThreadId long
3053
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
128
method Method
descriptor string
(Lorg/neo4j/cypher/internal/config/CypherConfiguration;)Lscala/PartialFunction;
hidden boolean
false
modifiers int
2
name string
fromCypherConfigurationBoolean
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
25.0.3
name string
java/net
hidden boolean
false
modifiers int
1025
name string
org/neo4j/cypher/internal/options/CypherOptionCompanion
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
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
org/neo4j/cypher/internal/options
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
53741265100
timedOut boolean
false
timeout long: millis
0

JavaMonitorInflate

profiling startTime duration eventThread stackTrace 11 17 21 25 26 27

Category: Java Application

Code Context

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

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

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

  return ret_code;
}

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

static void post_monitor_inflate_event(EventJavaMonitorInflate* event,
                                       const oop obj,
                                       ObjectSynchronizer::InflateCause cause) {
  assert(event != NULL, "invariant");
  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:

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

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

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

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

    // CASE: inflated

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

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

Examples 3
address ulong: address
32989943816
cause InflateCause
VM Internal
monitorClass 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
6
lineNumber int
717
method Method
descriptor string
()Ljava/util/zip/Inflater;
hidden boolean
false
modifiers int
0
name string
getInflater
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
java/util/zip/ZipFile$CleanableResource
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util/zip
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
887086958
address ulong: address
30190598024
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
25.0.3
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
25.0.3
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
1779560960
address ulong: address
30246821600
cause InflateCause
Monitor Enter
monitorClass 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
52
lineNumber int
73
method Method
descriptor string
(Lio/jenetics/util/Seq;)Lio/jenetics/util/ISeq;
hidden boolean
false
modifiers int
1
name string
eval
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
25.0.3
name string
java/net
hidden boolean
false
modifiers int
16
name string
io/jenetics/engine/ConcurrentEvaluator
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
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
io/jenetics/engine
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
5164535454

ObjectAllocationInNewTLAB

startTime eventThread stackTrace 11 17 21 25 26 27

Category: Java Application

Allocation in new Thread Local Allocation Buffer

Code Context

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

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

void AllocTracer::send_allocation_outside_tlab(Klass* klass, HeapWord* obj, size_t alloc_size, JavaThread* thread) {
  JFR_ONLY(JfrAllocationTracer tracer(klass, obj, alloc_size, true, thread);)
  EventObjectAllocationOutsideTLAB event;
  if (event.should_commit()) {
    event.set_objectClass(klass);
    event.set_allocationSize(alloc_size);
    event.commit();
  }
}

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

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

Configuration enabled stackTrace
default false true
profiling false true

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

Examples 3
allocationSize ulong: bytes
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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
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
586101152
tlabSize ulong: bytes
17192
allocationSize ulong: bytes
2544
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
64
lineNumber int
111
method Method
descriptor string
(Ljava/io/InputStream;Ljava/util/zip/Inflater;I)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/util/zip/InflaterInputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util/zip
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
531541061
tlabSize ulong: bytes
1302776
allocationSize ulong: bytes
32
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
12
lineNumber int
101
method Method
descriptor string
(I)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
1024
name string
java/lang/AbstractStringBuilder
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
621930837
tlabSize ulong: bytes
155104

ObjectAllocationOutsideTLAB

startTime eventThread stackTrace 11 17 21 25 26 27

Category: Java Application

Allocation outside Thread Local Allocation Buffers

Code Context

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

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

#if INCLUDE_JFR
#include "jfr/support/jfrAllocationTracer.hpp"
#endif

void AllocTracer::send_allocation_outside_tlab(Klass* klass, HeapWord* obj, size_t alloc_size, JavaThread* thread) {
  JFR_ONLY(JfrAllocationTracer tracer(klass, obj, alloc_size, true, thread);)
  EventObjectAllocationOutsideTLAB event;
  if (event.should_commit()) {
    event.set_objectClass(klass);
    event.set_allocationSize(alloc_size);
    event.commit();
  }
}

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

Configuration enabled stackTrace
default false true
profiling false true

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

Examples 3
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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
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
571747284
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
25.0.3
name string
java/net
hidden boolean
false
modifiers int
17
name string
scala/collection/immutable/TreeMap
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
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection/immutable
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
10
lineNumber int
83
method Method
descriptor string
(Lscala/collection/immutable/RedBlackTree$Tree;)Lscala/collection/immutable/TreeMap;
hidden boolean
false
modifiers int
2
name string
newMapOrSelf
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
25.0.3
name string
java/net
hidden boolean
false
modifiers int
17
name string
scala/collection/immutable/TreeMap
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
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection/immutable
type FrameType
Inlined
truncated boolean
false
startTime long: millis
14270237652
allocationSize ulong: bytes
49688
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
15
lineNumber int
3537
method Method
descriptor string
([BI)[B
hidden boolean
false
modifiers int
9
name string
copyOf
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/util/Arrays
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
520390848

ObjectAllocationSample

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

Category: Java Application

Code Context

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

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

static THREAD_LOCAL int64_t _last_allocated_bytes = 0;

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

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

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

Field Type Description
objectClass Class Object Class Class of allocated object
weight long: bytes Sample Weight The relative weight of the sample. Aggregating the weights for a large number of samples, for a particular class, thread or stack trace, gives a statistically accurate representation of the allocation pressure

Examples 3
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
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
25.0.3
name string
java/util
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
68
lineNumber int
120
method Method
descriptor string
()J
hidden boolean
false
modifiers int
9
name string
doPeriodic
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/jfr/internal/periodic/PeriodicEvents
package Package
exported boolean
false
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.jfr
name string
jdk.jfr
version string
25.0.3
name string
jdk/jfr/internal/periodic
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
376234403
weight long: bytes
91480
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/String
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
760
method Method
descriptor string
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hidden boolean
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modifiers int
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name string
newString
type Class
classLoader ClassLoader
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modifiers int
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java/lang/StringLatin1
package Package
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module Module
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name string
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location string
jrt:/java.base
name string
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version string
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name string
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type FrameType
Inlined
truncated boolean
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startTime long: millis
1213106619
weight long: bytes
583208
objectClass Class
classLoader ClassLoader
name string
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type Class
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modifiers int
1041
name string
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package Package
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stackTrace StackTrace
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lineNumber int
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method Method
descriptor string
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name string
app
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classLoader ClassLoader
name string
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type Class
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package Package
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module Module
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jrt:/java.base
name string
java.base
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name string
jdk/internal/loader
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name string
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package Package
exported boolean
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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
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module Module
classLoader ClassLoader
name string
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type Class
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location string
jrt:/java.base
name string
java.base
version string
25.0.3
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
576984297
weight long: bytes
45232

FileForce

default profiling startTime duration stackTrace 11 17 21 25 26 27

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

Category: Java Application

Force updates to be written to file

Code Context

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

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

package jdk.jfr.events;
import jdk.jfr.internal.handlers.EventHandler;
import jdk.jfr.internal.Utils;

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

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

package jdk.jfr.events;

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

@Name(Type.EVENT_NAME_PREFIX + "FileForce")
@Label("File Force")
@Category("Java Application")
@Description("Force updates to be written to file")
public final class FileForceEvent extends AbstractJDKEvent {

    // The order of these fields must be the same as the parameters in
    // EventHandler::write(..., String, boolean)

    @Label("Path")
    @Description("Full path of the file")
    public String path;

    @Label("Update Metadata")
    @Description("Whether the file metadata is updated")
    public boolean metaData;

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

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        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.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.class,

src/jdk.jfr/share/classes/jdk/jfr/internal/handlers/EventHandler.java:

    public boolean setRegistered(boolean registered) {
       return platformEventType.setRegistered(registered);
    }

    public void write(long start, long duration, String host, String address, int port, long timeout, long bytesRead, boolean endOfSTream) {
        throwError("SocketReadEvent");
    }

    public void write(long start, long duration, String host, String address, int port, long bytesWritten) {
        throwError("SocketWriteEvent");
    }

    public void write(long start, long duration, String path, boolean metadata) {
        throwError("FileForceEvent");
    }

    public void write(long start, long duration, String path, long bytesRead, boolean endOfFile) {
        throwError("FileReadEvent");
    }

    public void write(long start, long duration, String path, long bytesWritten) {
        throwError("FileWriteEvent");
    }

    public void write(long start, long duration, String path, Class<?> exceptionClass)  {

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

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

Examples 3
metaData boolean
true
path string
/tmp/jfr_sample12220442891844395361.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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
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false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
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
1915042926
metaData boolean
false
path string
/home/runner/work/jfrevents/jfrevents/harness-140614-780637367523948717/neo4j/neo4j-analytics/graphdb/data/databases/system/neostore.propertystore.db.index.keys.id
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
5
lineNumber int
219
method Method
descriptor string
(Z)V
hidden boolean
false
modifiers int
1
name string
force
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
25.0.3
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/neo4j/io/fs/StoreFileChannel
package Package
exported boolean
true
module Module
classLoader ClassLoader
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null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
org/neo4j/io/fs
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
36679310473
metaData boolean
false
path string
/home/runner/work/jfrevents/jfrevents/harness-140602-2306766489842645582/neo4j/neo4j-analytics/graphdb/data/databases/system/schema/index/token-lookup-1.0/2/index-2
stackTrace StackTrace
frames StackFrame
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force
type Class
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type Class
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hidden boolean
false
modifiers int
1
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java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/neo4j/io/fs/StoreFileChannel
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
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
org/neo4j/io/fs
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
31364126732

SocketWrite

default profiling startTime duration stackTrace 11 17 21 25 26 27

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

Category: Java Application

Writing data to a socket

Code Context

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

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

package jdk.jfr.events;
import jdk.jfr.internal.handlers.EventHandler;
import jdk.jfr.internal.Utils;

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

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

package jdk.jfr.events;

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

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

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

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

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

    @Label("Remote Port")

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

        DeserializationEvent.class,
        ProcessStartEvent.class,
        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.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.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/handlers/EventHandler.java:

    public boolean isRegistered() {
        return platformEventType.isRegistered();
    }

    public boolean setRegistered(boolean registered) {
       return platformEventType.setRegistered(registered);
    }

    public void write(long start, long duration, String host, String address, int port, long timeout, long bytesRead, boolean endOfSTream) {
        throwError("SocketReadEvent");
    }

    public void write(long start, long duration, String host, String address, int port, long bytesWritten) {
        throwError("SocketWriteEvent");
    }

    public void write(long start, long duration, String path, boolean metadata) {
        throwError("FileForceEvent");
    }

    public void write(long start, long duration, String path, long bytesRead, boolean endOfFile) {
        throwError("FileReadEvent");
    }

    public void write(long start, long duration, String path, long bytesWritten) {

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

Field Type Description
host string Remote Host
address string Remote Address
port int Remote Port
bytesWritten long: bytes Bytes Written Number of bytes written to the socket

Examples 3
address string
127.0.0.1
bytesWritten long: bytes
64
host string
127.0.0.1
port int
47240
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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
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
2044919825
address string
127.0.0.1
bytesWritten long: bytes
64
host string
127.0.0.1
port int
59854
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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
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
2196159546
address string
127.0.0.1
bytesWritten long: bytes
64
host string
127.0.0.1
port int
40323
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
25.0.3
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
25.0.3
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
1674216038

JavaErrorThrow

default profiling startTime duration stackTrace 11 17 21 25 26 27

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

Category: Java Application

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

Configuration enabled stackTrace
default true true
profiling true true

Field Type Description
message string Message
thrownClass Class Class

Examples 3
message string
'void java.lang.invoke.DirectMethodHandle$Holder.invokeInterface(java.lang.Object, java.lang.Object, java.lang.Object, java.lang.Object)'
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
16
lineNumber int
74
method Method
descriptor string
(Ljava/lang/String;)V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Error
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1415256985
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/NoSuchMethodError
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
message string
'long java.lang.invoke.DirectMethodHandle$Holder.invokeStatic(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
25.0.3
name string
java/lang
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
4628538050
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
25.0.3
name string
java/lang
message string
'java.lang.Object java.lang.invoke.Invokers$Holder.invokeExact_MT(java.lang.Object, java.lang.Object, java.lang.Object, java.lang.Object, 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
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java/lang/Error
package Package
exported boolean
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module Module
classLoader ClassLoader
name string
bootstrap
type Class
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location string
jrt:/java.base
name string
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version string
25.0.3
name string
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type FrameType
Interpreted
truncated boolean
true
startTime long: millis
4575692561
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
25.0.3
name string
java/lang

FileWrite

default profiling startTime duration stackTrace 11 17 21 25 26 27

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

Category: Java Application

Writing data to a file

Code Context

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

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

package jdk.jfr.events;
import jdk.jfr.internal.handlers.EventHandler;
import jdk.jfr.internal.Utils;

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

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

package jdk.jfr.events;

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

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

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

    @Label("Path")
    @Description("Full path of the file")
    public String path;

    @Label("Bytes Written")
    @Description("Number of bytes written to the file")
    @DataAmount

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

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        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.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,

src/jdk.jfr/share/classes/jdk/jfr/internal/handlers/EventHandler.java:

    public void write(long start, long duration, String host, String address, int port, long bytesWritten) {
        throwError("SocketWriteEvent");
    }

    public void write(long start, long duration, String path, boolean metadata) {
        throwError("FileForceEvent");
    }

    public void write(long start, long duration, String path, long bytesRead, boolean endOfFile) {
        throwError("FileReadEvent");
    }

    public void write(long start, long duration, String path, long bytesWritten) {
        throwError("FileWriteEvent");
    }

    public void write(long start, long duration, String path, Class<?> exceptionClass)  {
        throwError("ExceptionThrownEvent or ErrorThrownEvent");
    }

    private void throwError(String classes) {
        throw new InternalError("Method parameters don't match fields in class " + classes);
    }
}

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

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
bytesWritten long: bytes
9104
path string
launcher-140601-3475126292904839940/renaissance-harness_3/lib/scala3-library_3-3.3.1.jar
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
25.0.3
name string
java/io
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
434928558
bytesWritten long: bytes
8163
path string
harness-140614-780637367523948717/jdk-streams/lib/jdk-streams_3-0.15.0.jar
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
25.0.3
name string
java/io
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
836414223
bytesWritten long: bytes
1
path string
/tmp/jfr_agent6304371355823978465.jar
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
27
lineNumber int
844
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
2
name string
writeInt
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/zip/ZipOutputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util/zip
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
412096732

FileRead

default profiling startTime duration stackTrace 11 17 21 25 26 27

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

Category: Java Application

Reading data from a file

Code Context

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

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

package jdk.jfr.events;
import jdk.jfr.internal.handlers.EventHandler;
import jdk.jfr.internal.Utils;

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

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

package jdk.jfr.events;

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

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

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

    @Label("Path")
    @Description("Full path of the file")
    public String path;

    @Label("Bytes Read")
    @Description("Number of bytes read from the file (possibly 0)")
    @DataAmount

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

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        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.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,

src/jdk.jfr/share/classes/jdk/jfr/internal/handlers/EventHandler.java:

    public void write(long start, long duration, String host, String address, int port, long timeout, long bytesRead, boolean endOfSTream) {
        throwError("SocketReadEvent");
    }

    public void write(long start, long duration, String host, String address, int port, long bytesWritten) {
        throwError("SocketWriteEvent");
    }

    public void write(long start, long duration, String path, boolean metadata) {
        throwError("FileForceEvent");
    }

    public void write(long start, long duration, String path, long bytesRead, boolean endOfFile) {
        throwError("FileReadEvent");
    }

    public void write(long start, long duration, String path, long bytesWritten) {
        throwError("FileWriteEvent");
    }

    public void write(long start, long duration, String path, Class<?> exceptionClass)  {
        throwError("ExceptionThrownEvent or ErrorThrownEvent");
    }

    private void throwError(String classes) {

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

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
bytesRead long: bytes
309
endOfFile boolean
false
path string
/home/runner/work/jfrevents/jfrevents/.cache/renaissance.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$Source
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util/zip
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
384754011
bytesRead long: bytes
256
endOfFile boolean
false
path string
/dev/urandom
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
119
method Method
descriptor string
([BII)I
hidden boolean
false
modifiers int
1
name string
read
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/FilterInputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/io
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
408804477
bytesRead long: bytes
0
endOfFile boolean
true
path string
/opt/hostedtoolcache/Java_SapMachine_jdk/25.0.3/x64/conf/security/java.security
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
70
lineNumber int
505
method Method
descriptor string
()I
hidden boolean
false
modifiers int
0
name string
readLine
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
java/util/Properties$LineReader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
399649342

JavaExceptionThrow

startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ExceptionThrownEvent.java

Category: Java Application

An object derived from java.lang.Exception has been created

Configuration enabled stackTrace
default false true
profiling false true

Field Type Description
message string Message
thrownClass Class Class

Examples 3
message string
'java.lang.Object java.lang.invoke.DirectMethodHandle$Holder.invokeStatic(java.lang.Object, long, java.lang.Object)'
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
16
lineNumber int
74
method Method
descriptor string
(Ljava/lang/String;)V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Error
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
453903024
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
25.0.3
name string
java/lang
message string
scala.collection.immutable.Vector1
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
25.0.3
name string
java/lang
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
569930478
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
25.0.3
name string
java/lang
message string
'java.lang.Object java.lang.invoke.DirectMethodHandle$Holder.invokeStaticInit(java.lang.Object)'
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
44
lineNumber int
286
method Method
descriptor string
(Ljava/lang/String;)V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Throwable
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
397048147
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
25.0.3
name string
java/lang

SocketRead

default profiling startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/SocketReadEvent.java

Category: Java Application

Reading data from a socket

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/Handlers.java:

package jdk.jfr.events;
import jdk.jfr.internal.handlers.EventHandler;
import jdk.jfr.internal.Utils;

public final class Handlers {
    public static final EventHandler SOCKET_READ = Utils.getHandler(SocketReadEvent.class);
    public static final EventHandler SOCKET_WRITE = Utils.getHandler(SocketWriteEvent.class);
    public static final EventHandler FILE_READ = Utils.getHandler(FileReadEvent.class);
    public static final EventHandler FILE_WRITE = Utils.getHandler(FileWriteEvent.class);
    public static final EventHandler FILE_FORCE = Utils.getHandler(FileForceEvent.class);
    public static final EventHandler ERROR_THROWN = Utils.getHandler(ErrorThrownEvent.class);
    public static final EventHandler EXCEPTION_THROWN = Utils.getHandler(ExceptionThrownEvent.class);
}

src/jdk.jfr/share/classes/jdk/jfr/events/SocketReadEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "SocketRead")
@Label("Socket Read")
@Category("Java Application")
@Description("Reading data from a socket")
public final class SocketReadEvent extends AbstractJDKEvent {

    // The order of these fields must be the same as the parameters in
    // EventHandler::write(..., String, String, int, long, long, boolean)

    @Label("Remote Host")
    public String host;

    @Label("Remote Address")
    public String address;

    @Label("Remote Port")

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        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.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.X509CertificateEvent.class,

src/jdk.jfr/share/classes/jdk/jfr/internal/handlers/EventHandler.java:

    private final void readObject(ObjectInputStream in) throws IOException {
        throw new IOException("Class cannot be deserialized");
    }

    public boolean isRegistered() {
        return platformEventType.isRegistered();
    }

    public boolean setRegistered(boolean registered) {
       return platformEventType.setRegistered(registered);
    }

    public void write(long start, long duration, String host, String address, int port, long timeout, long bytesRead, boolean endOfSTream) {
        throwError("SocketReadEvent");
    }

    public void write(long start, long duration, String host, String address, int port, long bytesWritten) {
        throwError("SocketWriteEvent");
    }

    public void write(long start, long duration, String path, boolean metadata) {
        throwError("FileForceEvent");
    }

    public void write(long start, long duration, String path, long bytesRead, boolean endOfFile) {

Configuration enabled stackTrace threshold
default true true 20 ms
profiling true true 10 ms

Field Type Description
host string Remote Host
address string Remote Address
port int Remote Port
timeout long: millis Timeout Value
bytesRead long: bytes Bytes Read Number of bytes read from the socket
endOfStream boolean End of Stream If end of stream was reached

Examples 3
address string
127.0.0.1
bytesRead long: bytes
64
endOfStream boolean
false
host string
127.0.0.1
port int
39089
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
25.0.3
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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
2804235406
timeout long: millis
0
address string
127.0.0.1
bytesRead long: bytes
64
endOfStream boolean
false
host string
127.0.0.1
port int
38508
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
57
lineNumber int
552
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
socketIO
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1899270815
timeout long: millis
0
address string
127.0.0.1
bytesRead long: bytes
64
endOfStream boolean
false
host string
127.0.0.1
port int
41147
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
31
lineNumber int
547
method Method
descriptor string
(I)V
hidden boolean
false
modifiers int
4106
name string
lambda$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
25.0.3
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
25.0.3
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
2626762734
timeout long: millis
0

Java Application Statistics

JavaThreadStatistics

default profiling startTime duration every chunk 11 17 21 25 26 27

Category: Java Application / Statistics

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

 *
 *  If running inside a guest OS on top of a hypervisor in a virtualized environment,
 *  the total memory reported is the amount of memory configured for the guest OS by the hypervisor.
 */
TRACE_REQUEST_FUNC(PhysicalMemory) {
  u8 totalPhysicalMemory = os::physical_memory();
  EventPhysicalMemory event;
  event.set_totalSize(totalPhysicalMemory);
  event.set_usedSize(totalPhysicalMemory - os::available_memory());
  event.commit();
}

TRACE_REQUEST_FUNC(JavaThreadStatistics) {
  EventJavaThreadStatistics event;
  event.set_activeCount(ThreadService::get_live_thread_count());
  event.set_daemonCount(ThreadService::get_daemon_thread_count());
  event.set_accumulatedCount(ThreadService::get_total_thread_count());
  event.set_peakCount(ThreadService::get_peak_thread_count());
  event.commit();
}

TRACE_REQUEST_FUNC(ClassLoadingStatistics) {
#if INCLUDE_MANAGEMENT
  EventClassLoadingStatistics event;
  event.set_loadedClassCount(ClassLoadingService::loaded_class_count());

Configuration enabled period
default true 1000 ms
profiling true 1000 ms

Field Type Description
activeCount long Active Threads Number of live active threads including both daemon and non-daemon threads
daemonCount long Daemon Threads Number of live daemon threads
accumulatedCount long Accumulated Threads Number of threads created and also started since JVM start
peakCount long Peak Threads Peak live thread count since JVM start or when peak count was reset

Examples 3
accumulatedCount long
459
activeCount long
21
daemonCount long
16
peakCount long
22
startTime long: millis
22858129325
accumulatedCount long
220
activeCount long
53
daemonCount long
49
peakCount long
54
startTime long: millis
57337923360
accumulatedCount long
187
activeCount long
28
daemonCount long
27
peakCount long
53
startTime long: millis
30884278304

ClassLoadingStatistics

default profiling startTime duration every chunk 11 17 21 25 26 27

Category: Java Application / Statistics

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

TRACE_REQUEST_FUNC(JavaThreadStatistics) {
  EventJavaThreadStatistics event;
  event.set_activeCount(ThreadService::get_live_thread_count());
  event.set_daemonCount(ThreadService::get_daemon_thread_count());
  event.set_accumulatedCount(ThreadService::get_total_thread_count());
  event.set_peakCount(ThreadService::get_peak_thread_count());
  event.commit();
}

TRACE_REQUEST_FUNC(ClassLoadingStatistics) {
#if INCLUDE_MANAGEMENT
  EventClassLoadingStatistics event;
  event.set_loadedClassCount(ClassLoadingService::loaded_class_count());
  event.set_unloadedClassCount(ClassLoadingService::unloaded_class_count());
  event.commit();
#else
  log_debug(jfr, system)("Unable to generate requestable event ClassLoadingStatistics. The required jvm feature 'management' is missing.");
#endif
}

class JfrClassLoaderStatsClosure : public ClassLoaderStatsClosure {
public:
  JfrClassLoaderStatsClosure() : ClassLoaderStatsClosure(NULL) {}

Configuration enabled period
default true 1000 ms
profiling true 1000 ms

Field Type Description
loadedClassCount long Loaded Class Count Number of classes loaded since JVM start
unloadedClassCount long Unloaded Class Count Number of classes unloaded since JVM start

Examples 3
loadedClassCount long
21115
startTime long: millis
41303739758
unloadedClassCount long
1286
loadedClassCount long
4089
startTime long: millis
13658256938
unloadedClassCount long
252
loadedClassCount long
32776
startTime long: millis
69639244237
unloadedClassCount long
1353

ClassLoaderStatistics

default profiling startTime duration every chunk 11 17 21 25 26 27

Category: Java Application / Statistics

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  log_debug(jfr, system)("Unable to generate requestable event ClassLoadingStatistics. The required jvm feature 'management' is missing.");
#endif
}

class JfrClassLoaderStatsClosure : public ClassLoaderStatsClosure {
public:
  JfrClassLoaderStatsClosure() : ClassLoaderStatsClosure(NULL) {}

  bool do_entry(oop const& key, ClassLoaderStats const& cls) {
    const ClassLoaderData* this_cld = cls._class_loader != NULL ?
      java_lang_ClassLoader::loader_data_acquire(cls._class_loader) : NULL;
    const ClassLoaderData* parent_cld = cls._parent != NULL ?
      java_lang_ClassLoader::loader_data_acquire(cls._parent) : NULL;
    EventClassLoaderStatistics event;
    event.set_classLoader(this_cld);
    event.set_parentClassLoader(parent_cld);
    event.set_classLoaderData((intptr_t)cls._cld);
    event.set_classCount(cls._classes_count);
    event.set_chunkSize(cls._chunk_sz);
    event.set_blockSize(cls._block_sz);
    event.set_hiddenClassCount(cls._hidden_classes_count);
    event.set_hiddenChunkSize(cls._hidden_chunk_sz);
    event.set_hiddenBlockSize(cls._hidden_block_sz);
    event.commit();
    return true;

Configuration enabled period
default true everyChunk
profiling true everyChunk

Field Type Description
classLoader ClassLoader Class Loader
parentClassLoader ClassLoader Parent Class Loader
classLoaderData ulong: address ClassLoaderData Pointer Pointer to the ClassLoaderData structure in the JVM
classCount long Classes Number of loaded classes
chunkSize ulong: bytes Total Chunk Size Total size of all allocated metaspace chunks (each chunk has several blocks)
blockSize ulong: bytes Total Block Size Total size of all allocated metaspace blocks (each chunk has several blocks)
hiddenClassCount long 15+ Hidden Classes Number of hidden classes
hiddenChunkSize ulong: bytes 15+ Total Hidden Classes Chunk Size Total size of all allocated metaspace chunks for hidden classes (each chunk has several blocks)
hiddenBlockSize ulong: bytes 15+ Total Hidden Classes Block Size Total size of all allocated metaspace blocks for hidden classes (each chunk has several blocks)

Examples 3
blockSize ulong: bytes
704
chunkSize ulong: bytes
6144
classCount long
1
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
25.0.3
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
25.0.3
name string
jdk/internal/loader
location string
null
name string
null
version string
null
name string
jfr_sample
classLoaderData ulong: address
140142588841056
hiddenBlockSize ulong: bytes
0
hiddenChunkSize ulong: bytes
0
hiddenClassCount long
0
parentClassLoader ClassLoader
null
startTime long: millis
8156287174
blockSize ulong: bytes
5240
chunkSize ulong: bytes
6144
classCount long
2
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
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
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
org/neo4j/codegen
classLoaderData ulong: address
140680550519904
hiddenBlockSize ulong: bytes
0
hiddenChunkSize ulong: bytes
0
hiddenClassCount long
0
parentClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/net
startTime long: millis
36851145754
blockSize ulong: bytes
47027272
chunkSize ulong: bytes
47041536
classCount long
7737
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/net
classLoaderData ulong: address
140405451512368
hiddenBlockSize ulong: bytes
5184
hiddenChunkSize ulong: bytes
8192
hiddenClassCount long
4
parentClassLoader 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
25.0.3
name string
jdk/internal/loader
startTime long: millis
35332853764

ThreadAllocationStatistics

default profiling startTime every chunk 11 17 21 25 26 27

Category: Java Application / Statistics

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  GrowableArray<jlong> allocated(initial_size);
  GrowableArray<traceid> thread_ids(initial_size);
  JfrTicks time_stamp = JfrTicks::now();
  JfrJavaThreadIterator iter;
  while (iter.has_next()) {
    JavaThread* const jt = iter.next();
    assert(jt != NULL, "invariant");
    allocated.append(jt->cooked_allocated_bytes());
    thread_ids.append(JFR_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.

Configuration enabled period
default true everyChunk
profiling true everyChunk

Field Type Description
allocated ulong: bytes Allocated Approximate number of bytes allocated since thread start
thread Thread Thread

Examples 3
allocated ulong: bytes
9239448
startTime long: millis
9176318282
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-13
javaThreadId long
64
osName string
UCT-akka.actor.default-dispatcher-13
osThreadId long
2841
virtual boolean
false
allocated ulong: bytes
1312
startTime long: millis
373393402
thread Thread
group ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
C1 CompilerThread0
javaThreadId long
20
osName string
C1 CompilerThread0
osThreadId long
3293
virtual boolean
false
allocated ulong: bytes
0
startTime long: millis
9232279687
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
scala-execution-context-global-54
javaThreadId long
54
osName string
scala-execution-context-global-54
osThreadId long
2850
virtual boolean
false

FinalizerStatistics

default profiling startTime end of every chunk 18 21 25 26 27

Category: Java Application / Statistics

Per class statistics about finalizers

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrFinalizerStatisticsEvent.cpp:

static void send_event(const FinalizerEntry* fe, const InstanceKlass* ik, const JfrTicks& timestamp, Thread* thread) {
  assert(ik != NULL, "invariant");
  assert(ik->has_finalizer(), "invariant");
  assert(thread != NULL, "invariant");
  const char* const url = fe != nullptr ? fe->codesource() : nullptr;
  const traceid url_symbol_id = url != NULL ? JfrSymbolTable::add(url) : 0;
  EventFinalizerStatistics event(UNTIMED);
  event.set_endtime(timestamp);
  event.set_finalizableClass(ik);
  event.set_codeSource(url_symbol_id);
  if (fe == NULL) {
    event.set_objects(0);
    event.set_totalFinalizersRun(0);
  } else {
    assert(fe->klass() == ik, "invariant");
    event.set_objects(fe->objects_on_heap());
    event.set_totalFinalizersRun(fe->total_finalizers_run());
  }
  event.commit();
}

void JfrFinalizerStatisticsEvent::send_unload_event(const InstanceKlass* ik) {
  if (!EventFinalizerStatistics::is_enabled()) {
    return;
  }
  Thread* const thread = Thread::current();
  ResourceMark rm(thread);
  send_event(FinalizerService::lookup(ik, thread), ik, JfrTicks::now(), thread);
}

// Finalizer events generated by the periodic task will all have the same timestamp.

class FinalizerStatisticsEventClosure : public FinalizerEntryClosure {
 private:

Configuration enabled period
default true endChunk
profiling true endChunk

Field Type Description
finalizableClass Class Class Overriding Finalize
codeSource Symbol Code Source URL from where the class was loaded
objects ulong Finalizable Objects on Heap Number of objects on heap that can be finalized
totalFinalizersRun ulong Finalizers Run Total number of finalizers run since JVM start

Examples 3
codeSource Symbol
file:///home/runner/work/jfrevents/jfrevents/harness-140602-2306766489842645582/neo4j/lib/jna-5.13.0.jar
finalizableClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/net
hidden boolean
false
modifiers int
8
name string
com/sun/jna/Native$2
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
com/sun/jna
objects ulong
1
startTime long: millis
113582102453
totalFinalizersRun ulong
0
codeSource Symbol
file:///home/runner/work/jfrevents/jfrevents/harness-140614-780637367523948717/twitter-finagle/lib/netty-buffer-4.1.99.Final.jar
finalizableClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/net
hidden boolean
false
modifiers int
26
name string
io/netty/buffer/PoolThreadCache$FreeOnFinalize
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
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/buffer
objects ulong
8
startTime long: millis
127970713424
totalFinalizersRun ulong
0
codeSource Symbol
file:///home/runner/work/jfrevents/jfrevents/harness-140629-9485767527491855067/twitter-finagle/lib/netty-buffer-4.1.99.Final.jar
finalizableClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/net
hidden boolean
false
modifiers int
24
name string
io/netty/buffer/PoolArena$DirectArena
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/buffer
objects ulong
8
startTime long: millis
119520891059
totalFinalizersRun ulong
0

ExceptionStatistics

default profiling startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ExceptionStatisticsEvent.java

Category: Java Application / Statistics

Number of objects derived from java.lang.Throwable that have been created

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/ExceptionStatisticsEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.StackTrace;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "ExceptionStatistics")
@Label("Exception Statistics")
@Category({ "Java Application", "Statistics" })
@Description("Number of objects derived from java.lang.Throwable that have been created")
@StackTrace(false)
public final class ExceptionStatisticsEvent extends AbstractJDKEvent {

    @Label("Exceptions Created")
    public long throwables;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

        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.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,

        DirectBufferStatisticsEvent.class

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

    private static boolean initializationTriggered;

    @SuppressWarnings("unchecked")
    public static synchronized void initialize() {
        try {
            if (initializationTriggered == false) {
                for (Class<?> mirrorEventClass : mirrorEventClasses) {
                    SecuritySupport.registerMirror(((Class<? extends Event>)mirrorEventClass));
                }
                for (Class<?> eventClass : eventClasses) {
                    SecuritySupport.registerEvent((Class<? extends Event>) eventClass);
                }

                RequestEngine.addTrustedJDKHook(ExceptionStatisticsEvent.class, emitExceptionStatistics);
                RequestEngine.addTrustedJDKHook(DirectBufferStatisticsEvent.class, emitDirectBufferStatistics);

                initializeContainerEvents();
                initializationTriggered = true;
            }
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not initialize JDK events. " + e.getMessage());
        }
    }

    public static void addInstrumentation() {

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

        SecuritySupport.registerEvent(ContainerCPUUsageEvent.class);
        SecuritySupport.registerEvent(ContainerCPUThrottlingEvent.class);
        SecuritySupport.registerEvent(ContainerMemoryUsageEvent.class);
        SecuritySupport.registerEvent(ContainerIOUsageEvent.class);

        RequestEngine.addTrustedJDKHook(ContainerConfigurationEvent.class, emitContainerConfiguration);
        RequestEngine.addTrustedJDKHook(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        RequestEngine.addTrustedJDKHook(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        RequestEngine.addTrustedJDKHook(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        RequestEngine.addTrustedJDKHook(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void emitExceptionStatistics() {
        ExceptionStatisticsEvent t = new ExceptionStatisticsEvent();
        t.throwables = ThrowableTracer.numThrowables();
        t.commit();
    }

    private static void emitContainerConfiguration() {
        if (containerMetrics != null) {
            ContainerConfigurationEvent t = new ContainerConfigurationEvent();
            t.containerType = containerMetrics.getProvider();
            t.cpuSlicePeriod = containerMetrics.getCpuPeriod();
            t.cpuQuota = containerMetrics.getCpuQuota();
            t.cpuShares = containerMetrics.getCpuShares();

Configuration enabled period
default true 1000 ms
profiling true 1000 ms

Field Type Description
throwables long Exceptions Created

Examples 3
startTime long: millis
3454446554
throwables long
227
startTime long: millis
90169798145
throwables long
123037
startTime long: millis
44332216528
throwables long
15322

DirectBufferStatistics

default profiling startTime duration stackTrace 15 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/DirectBufferStatisticsEvent.java

Category: Java Application / Statistics

Statistics of direct buffer

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/DirectBufferStatisticsEvent.java:

package jdk.jfr.events;

import jdk.internal.misc.VM;
import jdk.internal.misc.VM.BufferPool;

import jdk.jfr.*;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "DirectBufferStatistics")
@Label("Direct Buffer Statistics")
@Description("Statistics of direct buffer")
public final class DirectBufferStatisticsEvent extends AbstractBufferStatisticsEvent {

    private static final BufferPool DIRECT_BUFFER_POOL = findPoolByName("direct");

    public DirectBufferStatisticsEvent() {
        super(DIRECT_BUFFER_POOL);
        this.maxCapacity = VM.maxDirectMemory();
    }

    @Label("Maximum Capacity")
    @Description("Maximum direct buffer capacity the process can use")
    @DataAmount
    final long maxCapacity;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

        SocketWriteEvent.class,
        ExceptionThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ErrorThrownEvent.class,
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,

        DirectBufferStatisticsEvent.class
    };

    // This is a list of the classes with instrumentation code that should be applied.
    private static final Class<?>[] instrumentationClasses = new Class<?>[] {
        FileInputStreamInstrumentor.class,
        FileOutputStreamInstrumentor.class,
        RandomAccessFileInstrumentor.class,
        FileChannelImplInstrumentor.class,
        SocketInputStreamInstrumentor.class,
        SocketOutputStreamInstrumentor.class,
        SocketChannelImplInstrumentor.class

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

    @SuppressWarnings("unchecked")
    public static synchronized void initialize() {
        try {
            if (initializationTriggered == false) {
                for (Class<?> mirrorEventClass : mirrorEventClasses) {
                    SecuritySupport.registerMirror(((Class<? extends Event>)mirrorEventClass));
                }
                for (Class<?> eventClass : eventClasses) {
                    SecuritySupport.registerEvent((Class<? extends Event>) eventClass);
                }

                RequestEngine.addTrustedJDKHook(ExceptionStatisticsEvent.class, emitExceptionStatistics);
                RequestEngine.addTrustedJDKHook(DirectBufferStatisticsEvent.class, emitDirectBufferStatistics);

                initializeContainerEvents();
                initializationTriggered = true;
            }
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not initialize JDK events. " + e.getMessage());
        }
    }

    public static void addInstrumentation() {
        try {

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

                    Logger.log(LogTag.JFR_SYSTEM, LogLevel.TRACE, "Processing instrumentation class: " + c);
                }
                return new JIClassInstrumentation(instrumentationClasses[i], klass, oldBytes).getNewBytes();
            }
        }
        return oldBytes;
    }

    public static void remove() {
        RequestEngine.removeHook(emitExceptionStatistics);
        RequestEngine.removeHook(emitDirectBufferStatistics);

        RequestEngine.removeHook(emitContainerConfiguration);
        RequestEngine.removeHook(emitContainerCPUUsage);
        RequestEngine.removeHook(emitContainerCPUThrottling);
        RequestEngine.removeHook(emitContainerMemoryUsage);
        RequestEngine.removeHook(emitContainerIOUsage);
    }

    private static void emitDirectBufferStatistics() {
        DirectBufferStatisticsEvent e = new DirectBufferStatisticsEvent();
        e.commit();
    }
}

Configuration enabled period
default true 5 s
profiling true 5 s

Examples 3
startTime long: millis
88125582388
startTime long: millis
10621406430
startTime long: millis
97929654021

Java Development Kit

X509Validation

startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/X509ValidationEvent.java

Category: Java Development Kit / Security

Serial numbers from X.509 Certificates forming chain of trust

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/X509ValidationEvent.java:

package jdk.internal.event;

/**
 * Event recording details of X.509 Certificate serial numbers
 * used in X509 cert path validation.
 */

public final class X509ValidationEvent extends Event {
    public long certificateId;
    public int certificatePosition;
    public long validationCounter;
}

src/java.base/share/classes/sun/security/provider/certpath/PKIXCertPathValidator.java:

        // only add a RevocationChecker if revocation is enabled and
        // a PKIXRevocationChecker has not already been added
        if (params.revocationEnabled() && !revCheckerAdded) {
            certPathCheckers.add(new RevocationChecker(anchor, params));
        }
        // add user-specified checkers
        certPathCheckers.addAll(checkers);

        PKIXMasterCertPathValidator.validate(params.certPath(),
                                             params.certificates(),
                                             certPathCheckers);

        X509ValidationEvent xve = new X509ValidationEvent();
        if (xve.shouldCommit() || EventHelper.isLoggingSecurity()) {
            int[] certIds = params.certificates().stream()
                    .mapToInt(Certificate::hashCode)
                    .toArray();
            int anchorCertId = (anchorCert != null) ?
                anchorCert.hashCode() : anchor.getCAPublicKey().hashCode();
            if (xve.shouldCommit()) {
                xve.certificateId = anchorCertId;
                int certificatePos = 1; // most trusted CA
                xve.certificatePosition = certificatePos;
                xve.validationCounter = validationCounter.incrementAndGet();

src/jdk.jfr/share/classes/jdk/jfr/events/X509ValidationEvent.java:

package jdk.jfr.events;

import jdk.jfr.*;
import jdk.jfr.internal.MirrorEvent;

@Category({"Java Development Kit", "Security"})
@Label("X509 Validation")
@Name("jdk.X509Validation")
@Description("Serial numbers from X.509 Certificates forming chain of trust")
@MirrorEvent(className = "jdk.internal.event.X509ValidationEvent")
public final class X509ValidationEvent extends AbstractJDKEvent {
    @CertificateId
    @Label("Certificate Id")
    public long certificateId;

    @Label("Certificate Position")
    @Description("Certificate position in chain of trust, 1 = trust anchor")
    public int certificatePosition;

    @Label("Validation Counter")
    public long validationCounter;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        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,

Configuration enabled stackTrace
default false true
profiling false true

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
certificateId long: certificateId
2389201834
certificatePosition int
2
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
520
lineNumber int
247
method Method
descriptor string
(Ljava/security/cert/TrustAnchor;Lsun/security/provider/certpath/PKIX$ValidatorParams;)Ljava/security/cert/PKIXCertPathValidatorResult;
hidden boolean
false
modifiers int
10
name string
validate
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
sun/security/provider/certpath/PKIXCertPathValidator
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
sun/security/provider/certpath
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1090650186
validationCounter long
1
certificateId long: certificateId
2389201834
certificatePosition int
2
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
520
lineNumber int
247
method Method
descriptor string
(Ljava/security/cert/TrustAnchor;Lsun/security/provider/certpath/PKIX$ValidatorParams;)Ljava/security/cert/PKIXCertPathValidatorResult;
hidden boolean
false
modifiers int
10
name string
validate
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
sun/security/provider/certpath/PKIXCertPathValidator
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
sun/security/provider/certpath
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
975357727
validationCounter long
1
certificateId long: certificateId
2389201834
certificatePosition int
2
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
520
lineNumber int
247
method Method
descriptor string
(Ljava/security/cert/TrustAnchor;Lsun/security/provider/certpath/PKIX$ValidatorParams;)Ljava/security/cert/PKIXCertPathValidatorResult;
hidden boolean
false
modifiers int
10
name string
validate
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
sun/security/provider/certpath/PKIXCertPathValidator
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
sun/security/provider/certpath
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
994620141
validationCounter long
1

Deserialization

startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/DeserializationEvent.java

Category: Java Development Kit / Serialization

Results of deserialization and ObjectInputFilter checks

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/DeserializationEvent.java:

package jdk.internal.event;

/**
 * Event details relating to deserialization.
 */

public final class DeserializationEvent extends Event {
    public boolean filterConfigured;
    public String filterStatus;
    public Class<?> type;
    public int arrayLength;
    public long objectReferences;
    public long depth;
    public long bytesRead;
    public Class<?> exceptionType;
    public String exceptionMessage;
}

src/java.base/share/classes/java/io/ObjectInputStream.java:

        ObjectInputFilter next = Config.getSerialFilterFactory()
                .apply(serialFilter, filter);
        if (serialFilter != null && next == null) {
            throw new IllegalStateException("filter can not be replaced with null filter");
        }
        serialFilter = next;
    }

    /**
     * Invokes the deserialization filter if non-null.
     *
     * If the filter rejects or an exception is thrown, throws InvalidClassException.
     *
     * Logs and/or commits a {@code DeserializationEvent}, if configured.
     *
     * @param clazz the class; may be null
     * @param arrayLength the array length requested; use {@code -1} if not creating an array
     * @throws InvalidClassException if it rejected by the filter or
     *        a {@link RuntimeException} is thrown
     */
    private void filterCheck(Class<?> clazz, int arrayLength)
            throws InvalidClassException {
        // Info about the stream is not available if overridden by subclass, return 0
        long bytesRead = (bin == null) ? 0 : bin.getBytesRead();
        RuntimeException ex = null;

src/java.base/share/classes/java/io/ObjectInputStream.java:

                status = ObjectInputFilter.Status.REJECTED;
                ex = e;
            }
            if (Logging.filterLogger != null) {
                // Debug logging of filter checks that fail; Tracing for those that succeed
                Logging.filterLogger.log(status == null || status == ObjectInputFilter.Status.REJECTED
                                ? Logger.Level.DEBUG
                                : Logger.Level.TRACE,
                        "ObjectInputFilter {0}: {1}, array length: {2}, nRefs: {3}, depth: {4}, bytes: {5}, ex: {6}",
                        status, clazz, arrayLength, totalObjectRefs, depth, bytesRead,
                        Objects.toString(ex, "n/a"));
            }
        }
        DeserializationEvent event = new DeserializationEvent();
        if (event.shouldCommit()) {
            event.filterConfigured = serialFilter != null;
            event.filterStatus = status != null ? status.name() : null;
            event.type = clazz;
            event.arrayLength = arrayLength;
            event.objectReferences = totalObjectRefs;
            event.depth = depth;
            event.bytesRead = bytesRead;
            event.exceptionType = ex != null ? ex.getClass() : null;
            event.exceptionMessage = ex != null ? ex.getMessage() : null;
            event.commit();

src/jdk.jfr/share/classes/jdk/jfr/events/DeserializationEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.MirrorEvent;

@Category({"Java Development Kit", "Serialization"})
@Label("Deserialization")
@Name("jdk.Deserialization")
@Description("Results of deserialization and ObjectInputFilter checks")
@MirrorEvent(className = "jdk.internal.event.DeserializationEvent")
public final class DeserializationEvent extends AbstractJDKEvent {

    @Label("Filter Configured")
    public boolean filterConfigured;

    @Label("Filter Status")
    public String filterStatus;

    @Label ("Type")
    public Class<?> type;

    @Label ("Array Length")

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        TLSHandshakeEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,

Configuration enabled stackTrace
default false true
profiling false true

Field Type Description
filterConfigured boolean Filter Configured
filterStatus string Filter Status
type Class Type
arrayLength int Array Length
objectReferences long Object References
depth long Depth
bytesRead long Bytes Read
exceptionType Class Exception Type
exceptionMessage string Exception Message

Examples 3
arrayLength int
-1
bytesRead long
45
depth long
1
exceptionMessage string
null
exceptionType Class
null
filterConfigured boolean
false
filterStatus string
null
objectReferences long
1
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
304
lineNumber int
1348
method Method
descriptor string
(Ljava/lang/Class;I)V
hidden boolean
false
modifiers int
2
name string
filterCheck
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/ObjectInputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/io
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1030634359
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
25.0.3
name string
java/util
arrayLength int
3
bytesRead long
57
depth long
1
exceptionMessage string
null
exceptionType Class
null
filterConfigured boolean
false
filterStatus string
null
objectReferences long
2
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
304
lineNumber int
1348
method Method
descriptor string
(Ljava/lang/Class;I)V
hidden boolean
false
modifiers int
2
name string
filterCheck
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/ObjectInputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/io
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1172640664
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[Ljava/lang/Object;
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
arrayLength int
3
bytesRead long
57
depth long
1
exceptionMessage string
null
exceptionType Class
null
filterConfigured boolean
false
filterStatus string
null
objectReferences long
2
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
304
lineNumber int
1348
method Method
descriptor string
(Ljava/lang/Class;I)V
hidden boolean
false
modifiers int
2
name string
filterCheck
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/ObjectInputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/io
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1068896579
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[Ljava/lang/Object;
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang

TLSHandshake

startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/TLSHandshakeEvent.java

Category: Java Development Kit / Security

Parameters used in TLS Handshake

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/TLSHandshakeEvent.java:

package jdk.internal.event;

/**
 * Event recording details of successful TLS handshakes.
 */

public final class TLSHandshakeEvent extends Event {
    public String peerHost;
    public int peerPort;
    public String protocolVersion;
    public String cipherSuite;
    public long certificateId;
}

src/java.base/share/classes/sun/security/ssl/Finished.java:

            // May need to retransmit the last flight for DTLS.
            if (!shc.sslContext.isDTLS()) {
                shc.conContext.finishHandshake();
            }
            recordEvent(shc.conContext.conSession);

            //
            // produce
            NewSessionTicket.t13PosthandshakeProducer.produce(shc);
        }
    }

    private static void recordEvent(SSLSessionImpl session) {
        TLSHandshakeEvent event = new TLSHandshakeEvent();
        if (event.shouldCommit() || EventHelper.isLoggingSecurity()) {
            int peerCertificateId = 0;
            try {
                // use hash code for Id
                peerCertificateId = session
                        .getCertificateChain()[0]
                        .hashCode();
            } catch (SSLPeerUnverifiedException e) {
                 // not verified msg
            }
            if (event.shouldCommit()) {

src/jdk.jfr/share/classes/jdk/jfr/events/TLSHandshakeEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.MirrorEvent;

@Category({"Java Development Kit", "Security"})
@Label("TLS Handshake")
@Name("jdk.TLSHandshake")
@Description("Parameters used in TLS Handshake")
@MirrorEvent(className = "jdk.internal.event.TLSHandshakeEvent")
public final class TLSHandshakeEvent extends AbstractJDKEvent {
    @Label("Peer Host")
    public String peerHost;

    @Label("Peer Port")
    public int peerPort;

    @Label("Protocol Version")
    public String protocolVersion;

    @Label("Cipher Suite")
    public String cipherSuite;

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        TLSHandshakeEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ExceptionThrownEvent.class,

Configuration enabled stackTrace
default false true
profiling false true

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
certificateId long: certificateId
2494060369
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
25.0.3
name string
sun/security/ssl
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1131575678
certificateId long: certificateId
2494060369
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
25.0.3
name string
sun/security/ssl
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1009800509
certificateId long: certificateId
2494060369
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
25.0.3
name string
sun/security/ssl
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
1039076439

SecurityPropertyModification

startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/SecurityPropertyModificationEvent.java

Category: Java Development Kit / Security

Modification of Security property

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/SecurityPropertyModificationEvent.java:

package jdk.internal.event;

/**
 * Event details relating to the modification of a Security property.
 */

public final class SecurityPropertyModificationEvent extends Event {
    public String key;
    public String value;
}

src/java.base/share/classes/java/security/Security.java:

     *          if a security manager exists and its {@link
     *          java.lang.SecurityManager#checkPermission} method
     *          denies access to set the specified security property value
     * @throws  NullPointerException if key or datum is 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/events/SecurityPropertyModificationEvent.java:

package jdk.jfr.events;

import jdk.jfr.*;
import jdk.jfr.internal.MirrorEvent;

@Category({"Java Development Kit", "Security"})
@Label("Security Property Modification")
@Name("jdk.SecurityPropertyModification")
@Description("Modification of Security property")
@MirrorEvent(className = "jdk.internal.event.SecurityPropertyModificationEvent")
public final class SecurityPropertyModificationEvent extends AbstractJDKEvent {
    @Label("Key")
    public String key;

    @Label("Value")
    public String value;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        TLSHandshakeEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,

Configuration enabled stackTrace
default false true
profiling false true

Field Type Description
key string Key
value string Value

Examples 3
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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
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
1203506601
value string
secp112r1
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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
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
1061260590
value string
secp112r1
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$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
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
1098380642
value string
secp112r1

X509Certificate

startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/X509CertificateEvent.java

Category: Java Development Kit / Security

Details of X.509 Certificate parsed by JDK

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/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;
}

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/jdk.jfr/share/classes/jdk/jfr/events/X509CertificateEvent.java:

package jdk.jfr.events;

import jdk.jfr.*;
import jdk.jfr.internal.MirrorEvent;

@Category({"Java Development Kit", "Security"})
@Label("X509 Certificate")
@Name("jdk.X509Certificate")
@Description("Details of X.509 Certificate parsed by JDK")
@MirrorEvent(className = "jdk.internal.event.X509CertificateEvent")
public final class X509CertificateEvent extends AbstractJDKEvent {
    @Label("Signature Algorithm")
    public String algorithm;

    @Label("Serial Number")
    public String serialNumber;

    @Label("Subject")
    public String subject;

    @Label("Issuer")
    public String issuer;

    @Label("Key Type")

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        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,

Configuration enabled stackTrace
default false true
profiling false true

Field Type Description
algorithm string Signature Algorithm
serialNumber string Serial Number
subject string Subject
issuer string Issuer
keyType string Key Type
keyLength int Key Length
certificateId long: certificateId Certificate Id
validFrom long: epochmillis Valid From
validUntil long: epochmillis Valid Until

Examples 3
algorithm string
SHA384withRSA
certificateId long: certificateId
3406046841
issuer string
CN=DigiCert Trusted Root G4, OU=www.digicert.com, O=DigiCert Inc, C=US
keyLength int
4096
keyType string
RSA
serialNumber string
08:ad:40:b2:60:d2:9c:4c:9f:5e:cd:a9:bd:93:ae:d9
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
25.0.3
name string
sun/security/jca
type FrameType
Interpreted
truncated boolean
true
startTime long: millis
37057406132
subject string
CN=DigiCert Trusted G4 Code Signing RSA4096 SHA384 2021 CA1, O="DigiCert, Inc.", C=US
validFrom long: epochmillis
1619654400000
validUntil long: epochmillis
2093039999000
algorithm string
SHA384withRSA
certificateId long: certificateId
3406046841
issuer string
CN=DigiCert Trusted Root G4, OU=www.digicert.com, O=DigiCert Inc, C=US
keyLength int
4096
keyType string
RSA
serialNumber string
08:ad:40:b2:60:d2:9c:4c:9f:5e:cd:a9:bd:93:ae:d9
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
25.0.3
name string
sun/security/jca
type FrameType
Interpreted
truncated boolean
true
startTime long: millis
31223702195
subject string
CN=DigiCert Trusted G4 Code Signing RSA4096 SHA384 2021 CA1, O="DigiCert, Inc.", C=US
validFrom long: epochmillis
1619654400000
validUntil long: epochmillis
2093039999000
algorithm string
SHA384withRSA
certificateId long: certificateId
657172038
issuer string
CN=GTS Root R1, O=Google Trust Services LLC, C=US
keyLength int
4096
keyType string
RSA
serialNumber string
02:03:e5:93:6f:31:b0:13:49:88:6b:a2:17
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
25.0.3
name string
sun/security/jca
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
768915366
subject string
CN=GTS Root R1, O=Google Trust Services LLC, C=US
validFrom long: epochmillis
1466553600000
validUntil long: epochmillis
2097705600000

Operating System

OSInformation

default profiling startTime duration end of every chunk 11 17 21 25 26 27

Category: Operating System

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  event.set_jvmVersion(VM_Version::internal_vm_info_string());
  event.set_javaArguments(Arguments::java_command());
  event.set_jvmArguments(Arguments::jvm_args());
  event.set_jvmFlags(Arguments::jvm_flags());
  event.set_jvmStartTime(Management::vm_init_done_time());
  event.set_pid(os::current_process_id());
  event.commit();
 }

TRACE_REQUEST_FUNC(OSInformation) {
  ResourceMark rm;
  char* os_name = NEW_RESOURCE_ARRAY(char, 2048);
  JfrOSInterface::os_version(&os_name);
  EventOSInformation event;
  event.set_osVersion(os_name);
  event.commit();
}

TRACE_REQUEST_FUNC(VirtualizationInformation) {
  EventVirtualizationInformation event;
  event.set_name(JfrOSInterface::virtualization_name());
  event.commit();
}

TRACE_REQUEST_FUNC(ModuleRequire) {

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
osVersion string OS Version

Examples 3
osVersion string
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=24.04 DISTRIB_CODENAME=noble DISTRIB_DESCRIPTION="Ubuntu 24.04.4 LTS" uname: Linux 6.17.0-1015-azure #15~24.04.1-Ubuntu SMP Wed May 6 22:37:49 UTC 2026 x86_64 libc: glibc 2.39 NPTL 2.39
startTime long: millis
17207056473
osVersion string
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=24.04 DISTRIB_CODENAME=noble DISTRIB_DESCRIPTION="Ubuntu 24.04.4 LTS" uname: Linux 6.17.0-1015-azure #15~24.04.1-Ubuntu SMP Wed May 6 22:37:49 UTC 2026 x86_64 libc: glibc 2.39 NPTL 2.39
startTime long: millis
373113028
osVersion string
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=24.04 DISTRIB_CODENAME=noble DISTRIB_DESCRIPTION="Ubuntu 24.04.4 LTS" uname: Linux 6.17.0-1015-azure #15~24.04.1-Ubuntu SMP Wed May 6 22:37:49 UTC 2026 x86_64 libc: glibc 2.39 NPTL 2.39
startTime long: millis
101865878350

VirtualizationInformation

default profiling startTime duration end of every chunk 11 17 21 25 26 27

Category: Operating System

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  event.commit();
 }

TRACE_REQUEST_FUNC(OSInformation) {
  ResourceMark rm;
  char* os_name = NEW_RESOURCE_ARRAY(char, 2048);
  JfrOSInterface::os_version(&os_name);
  EventOSInformation event;
  event.set_osVersion(os_name);
  event.commit();
}

TRACE_REQUEST_FUNC(VirtualizationInformation) {
  EventVirtualizationInformation event;
  event.set_name(JfrOSInterface::virtualization_name());
  event.commit();
}

TRACE_REQUEST_FUNC(ModuleRequire) {
  JfrModuleEvent::generate_module_dependency_events();
}

TRACE_REQUEST_FUNC(ModuleExport) {
  JfrModuleEvent::generate_module_export_events();
}

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
name string Name

Examples 3
name string
Hyper-V virtualization
startTime long: millis
63705028203
name string
Hyper-V virtualization
startTime long: millis
8304201142
name string
Hyper-V virtualization
startTime long: millis
79134384602

InitialEnvironmentVariable

default profiling startTime end of every chunk 11 17 21 25 26 27

Category: Operating System

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrOSInterface.cpp:

  } else if (vrt == PowerFullPartitionMode) {
    return "Power full partition";
  }

  return "No virtualization detected";
}

int JfrOSInterface::generate_initial_environment_variable_events() {
  if (os::get_environ() == NULL) {
    return OS_ERR;
  }

  if (EventInitialEnvironmentVariable::is_enabled()) {
    // One time stamp for all events, so they can be grouped together
    JfrTicks time_stamp = JfrTicks::now();
    for (char** p = os::get_environ(); *p != NULL; p++) {
      char* variable = *p;
      char* equal_sign = strchr(variable, '=');
      if (equal_sign != NULL) {
        // Extract key/value
        ResourceMark rm;
        ptrdiff_t key_length = equal_sign - variable;
        char* key = NEW_RESOURCE_ARRAY(char, key_length + 1);
        char* value = equal_sign + 1;
        strncpy(key, variable, key_length);
        key[key_length] = '\0';
        EventInitialEnvironmentVariable event(UNTIMED);
        event.set_endtime(time_stamp);
        event.set_key(key);
        event.set_value(value);
        event.commit();
      }
    }
  }
  return OS_OK;
}

int JfrOSInterface::system_processes(SystemProcess** sys_processes, int* no_of_sys_processes) {

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
key string Key
value string Value

Examples 3
key string
GOROOT_1_24_X64
startTime long: millis
373126823
value string
/opt/hostedtoolcache/go/1.24.13/x64
key string
JAVA_HOME_25_X64
startTime long: millis
359590222
value string
/opt/hostedtoolcache/Java_SapMachine_jdk/25.0.3/x64
key string
DOTNET_MULTILEVEL_LOOKUP
startTime long: millis
384285207
value string
0

SystemProcess

default profiling startTime duration end of every chunk 11 17 21 25 26 27

Category: Operating System

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

    while (processes != NULL) {
      SystemProcess* tmp = processes;
      const char* info = processes->command_line();
      if (info == NULL) {
         info = processes->path();
      }
      if (info == NULL) {
         info = processes->name();
      }
      if (info == NULL) {
         info = "?";
      }
      jio_snprintf(pid_buf, sizeof(pid_buf), "%d", processes->pid());
      EventSystemProcess event(UNTIMED);
      event.set_pid(pid_buf);
      event.set_commandLine(info);
      event.set_starttime(start_time);
      event.set_endtime(end_time);
      event.commit();
      processes = processes->next();
      delete tmp;
    }
  }
}

Configuration enabled period
default true endChunk
profiling true endChunk

Field Type Description
pid string Process Identifier
commandLine string Command Line

Examples 3
commandLine string
kworker/R-nvme-auth-wq
pid string
83
startTime long: millis
8149245947
commandLine string
/tmp/provjobd3065236252
pid string
2102
startTime long: millis
8558478061
commandLine string
kworker/R-devfreq_wq
pid string
68
startTime long: millis
8859822156

CPUInformation

default profiling startTime duration end of every chunk 11 17 21 25 26 27

Category: Operating System / Processor

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

TRACE_REQUEST_FUNC(CPUInformation) {
  CPUInformation cpu_info;
  int ret_val = JfrOSInterface::cpu_information(cpu_info);
  if (ret_val == OS_ERR) {
    log_debug(jfr, system)( "Unable to generate requestable event CPUInformation");
    return;
  }
  if (ret_val == FUNCTIONALITY_NOT_IMPLEMENTED) {
     return;
  }
  if (ret_val == OS_OK) {
    EventCPUInformation event;
    event.set_cpu(cpu_info.cpu_name());
    event.set_description(cpu_info.cpu_description());
    event.set_sockets(cpu_info.number_of_sockets());
    event.set_cores(cpu_info.number_of_cores());
    event.set_hwThreads(cpu_info.number_of_hardware_threads());
    event.commit();
  }
}

TRACE_REQUEST_FUNC(CPULoad) {
  double u = 0; // user time

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
cpu string Type
description string Description
sockets uint Sockets
cores uint Cores
hwThreads uint Hardware Threads

Examples 3
cores uint
16
cpu string
AMD Unknown x86 (HT) SSE SSE2 SSE3 SSSE3 SSE4.1 SSE4.2 SSE4A AMD64
description string
Brand: AMD EPYC 7763 64-Core Processor , Vendor: AuthenticAMD Family: Unknown x86 (0x19), Model: <unknown> (0x1), Stepping: 0x1 Ext. family: 0xa, Ext. model: 0x0, Type: 0x0, Signature: 0x00a00f11 Features: ebx: 0x02100800, ecx: 0xfeda3203, edx: 0x178bfbff Ext. features: eax: 0x00a00f1
hwThreads uint
4
sockets uint
1
startTime long: millis
8304223524
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
359638514
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
87038351190

CPUTimeStampCounter

default profiling startTime duration end of every chunk 11 17 21 25 26 27

Category: Operating System / Processor

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

    event.commit();
  }
}

TRACE_REQUEST_FUNC(ThreadCPULoad) {
  JfrThreadCPULoadEvent::send_events();
}

TRACE_REQUEST_FUNC(NetworkUtilization) {
  JfrNetworkUtilization::send_events();
}

TRACE_REQUEST_FUNC(CPUTimeStampCounter) {
  EventCPUTimeStampCounter event;
  event.set_fastTimeEnabled(JfrTime::is_ft_enabled());
  event.set_fastTimeAutoEnabled(JfrTime::is_ft_supported());
  event.set_osFrequency(os::elapsed_frequency());
  event.set_fastTimeFrequency(JfrTime::frequency());
  event.commit();
}

TRACE_REQUEST_FUNC(SystemProcess) {
  char pid_buf[16];
  SystemProcess* processes = NULL;
  int num_of_processes = 0;

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
fastTimeEnabled boolean Fast Time
fastTimeAutoEnabled boolean Trusted Platform
osFrequency long: hertz OS Frequency
fastTimeFrequency long: hertz Fast Time Frequency

Examples 3
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
28322523578
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
373172629
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
126448845623

CPULoad

default profiling startTime duration every chunk 11 17 21 25 26 27

Category: Operating System / Processor

OS CPU Load

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  double t = 0; // total time
  int ret_val = OS_ERR;
  {
    // Can take some time on certain platforms, especially under heavy load.
    // Transition to native to avoid unnecessary stalls for pending safepoint synchronizations.
    ThreadToNativeFromVM transition(JavaThread::current());
    ret_val = JfrOSInterface::cpu_loads_process(&u, &s, &t);
  }
  if (ret_val == OS_ERR) {
    log_debug(jfr, system)( "Unable to generate requestable event CPULoad");
    return;
  }
  if (ret_val == OS_OK) {
    EventCPULoad event;
    event.set_jvmUser((float)u);
    event.set_jvmSystem((float)s);
    event.set_machineTotal((float)t);
    event.commit();
  }
}

TRACE_REQUEST_FUNC(ThreadCPULoad) {
  JfrThreadCPULoadEvent::send_events();
}

Configuration enabled period
default true 1000 ms
profiling true 1000 ms

Field Type Description
jvmUser float: percentage JVM User
jvmSystem float: percentage JVM System
machineTotal float: percentage Machine Total

Examples 3
jvmSystem float: percentage
0.017721519
jvmUser float: percentage
0.89873415
machineTotal float: percentage
0.9265823
startTime long: millis
31888056581
jvmSystem float: percentage
0.020512821
jvmUser float: percentage
0.34358975
machineTotal float: percentage
0.36410257
startTime long: millis
13658246318
jvmSystem float: percentage
0.047738694
jvmUser float: percentage
0.89447236
machineTotal float: percentage
0.94221103
startTime long: millis
14627307421

ThreadCPULoad

default profiling startTime duration eventThread every chunk 11 17 21 25 26 27

Category: Operating System / Processor

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrThreadCPULoadEvent.hpp:

#ifndef SHARE_JFR_PERIODIC_JFRTHREADCPULOADEVENT_HPP
#define SHARE_JFR_PERIODIC_JFRTHREADCPULOADEVENT_HPP

#include "jni.h"
#include "memory/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

src/hotspot/share/jfr/periodic/jfrThreadCPULoadEvent.cpp:

int JfrThreadCPULoadEvent::get_processor_count() {
  int cur_processor_count = os::active_processor_count();
  int last_processor_count = _last_active_processor_count;
  _last_active_processor_count = cur_processor_count;

  // If the number of processors decreases, we don't know at what point during
  // the sample interval this happened, so use the largest number to try
  // to avoid percentages above 100%
  return MAX2(cur_processor_count, last_processor_count);
}

// Returns false if the thread has not been scheduled since the last call to updateEvent
// (i.e. the delta for both system and user time is 0 milliseconds)
bool JfrThreadCPULoadEvent::update_event(EventThreadCPULoad& event, JavaThread* thread, jlong cur_wallclock_time, int processor_count) {
  JfrThreadLocal* const tl = thread->jfr_thread_local();

  jlong cur_cpu_time = os::thread_cpu_time(thread, true);
  jlong prev_cpu_time = tl->get_cpu_time();

  jlong prev_wallclock_time = tl->get_wallclock_time();
  tl->set_wallclock_time(cur_wallclock_time);

  // Threshold of 1 ms
  if (cur_cpu_time - prev_cpu_time < 1 * NANOSECS_PER_MILLISEC) {
    return false;

src/hotspot/share/jfr/periodic/jfrThreadCPULoadEvent.cpp:

  Thread* periodic_thread = Thread::current();
  JfrThreadLocal* const periodic_thread_tl = periodic_thread->jfr_thread_local();
  traceid periodic_thread_id = periodic_thread_tl->thread_id();
  const int processor_count = JfrThreadCPULoadEvent::get_processor_count();
  JfrTicks event_time = JfrTicks::now();
  jlong cur_wallclock_time = JfrThreadCPULoadEvent::get_wallclock_time();

  JfrJavaThreadIterator iter;
  int number_of_threads = 0;
  while (iter.has_next()) {
    JavaThread* const jt = iter.next();
    assert(jt != NULL, "invariant");
    ++number_of_threads;
    EventThreadCPULoad event(UNTIMED);
    if (JfrThreadCPULoadEvent::update_event(event, jt, cur_wallclock_time, processor_count)) {
      event.set_starttime(event_time);
      if (jt != periodic_thread) {
        // Commit reads the thread id from this thread's trace data, so put it there temporarily
        periodic_thread_tl->set_thread_id(JFR_THREAD_ID(jt));
      } else {
        periodic_thread_tl->set_thread_id(periodic_thread_id);
      }
      event.commit();
    }
  }
  log_trace(jfr)("Measured CPU usage for %d threads in %.3f milliseconds", number_of_threads,
    (double)(JfrTicks::now() - event_time).milliseconds());
  // Restore this thread's thread id
  periodic_thread_tl->set_thread_id(periodic_thread_id);
}

void JfrThreadCPULoadEvent::send_event_for_thread(JavaThread* jt) {
  EventThreadCPULoad event;
  if (event.should_commit()) {
    if (update_event(event, jt, get_wallclock_time(), get_processor_count())) {
      event.commit();
    }
  }
}

Configuration enabled period
default true 10 s
profiling true 10 s

Field Type Description
user float: percentage User Mode CPU Load User mode thread CPU load
system float: percentage System Mode CPU Load System mode thread CPU load

Examples 3
startTime long: millis
12449362257
system float: percentage
0.0
user float: percentage
0.0012600009
startTime long: millis
13659922241
system float: percentage
0.22047839
user float: percentage
0.0
startTime long: millis
10507658491
system float: percentage
0.0013355021
user float: percentage
0.06303243

ThreadContextSwitchRate

default profiling startTime duration every chunk 11 17 21 25 26 27

Category: Operating System / Processor

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

    // Can take some time on certain platforms, especially under heavy load.
    // Transition to native to avoid unnecessary stalls for pending safepoint synchronizations.
    ThreadToNativeFromVM transition(JavaThread::current());
    ret_val = JfrOSInterface::context_switch_rate(&rate);
  }
  if (ret_val == OS_ERR) {
    log_debug(jfr, system)( "Unable to generate requestable event ThreadContextSwitchRate");
    return;
  }
  if (ret_val == FUNCTIONALITY_NOT_IMPLEMENTED) {
    return;
  }
  if (ret_val == OS_OK) {
    EventThreadContextSwitchRate event;
    event.set_switchRate((float)rate + 0.0f);
    event.commit();
  }
}

#define SEND_FLAGS_OF_TYPE(eventType, flagType)                   \
  do {                                                            \
    JVMFlag *flag = JVMFlag::flags;                               \
    while (flag->name() != NULL) {                                \
      if (flag->is_ ## flagType()) {                              \
        if (flag->is_unlocked()) {                                \

Configuration enabled period
default true 10 s
profiling true 10 s

Field Type Description
switchRate float: hertz Switch Rate Number of context switches per second

Examples 3
startTime long: millis
103025812191
switchRate float: hertz
3839.8657
startTime long: millis
10621909881
switchRate float: hertz
9667.025
startTime long: millis
62404520146
switchRate float: hertz
6067.0127

NetworkUtilization

default profiling startTime every chunk 11 17 21 25 26 27

Category: Operating System / Network

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrNetworkUtilization.cpp:

  static JfrTicks last_sample_instant;
  const JfrTicks cur_time = JfrTicks::now();
  if (cur_time > last_sample_instant) {
    const JfrTickspan interval = cur_time - last_sample_instant;
    for (NetworkInterface *cur = network_interfaces; cur != NULL; cur = cur->next()) {
      InterfaceEntry& entry = get_entry(cur);
      const uint64_t current_bytes_in = cur->get_bytes_in();
      const uint64_t current_bytes_out = cur->get_bytes_out();
      const uint64_t read_rate = rate_per_second(current_bytes_in, entry.bytes_in, interval);
      const uint64_t write_rate = rate_per_second(current_bytes_out, entry.bytes_out, interval);
      if (read_rate > 0 || write_rate > 0) {
        write_interface_constant(entry);
        EventNetworkUtilization event(UNTIMED);
        event.set_starttime(cur_time);
        event.set_endtime(cur_time);
        event.set_networkInterface(entry.id);
        event.set_readRate(8 * read_rate);
        event.set_writeRate(8 * write_rate);
        event.commit();
      }
      // update existing entry with new values
      entry.bytes_in = current_bytes_in;
      entry.bytes_out = current_bytes_out;
    }

Configuration enabled period
default true 5 s
profiling true 5 s

Field Type Description
networkInterface NetworkInterfaceName Network Interface Network Interface Name
readRate long: bits-per-second Read Rate Number of incoming bits per second
writeRate long: bits-per-second Write Rate Number of outgoing bits per second

Examples 3
networkInterface NetworkInterfaceName
eth0
readRate long: bits-per-second
6696
startTime long: millis
20832985739
writeRate long: bits-per-second
41736
networkInterface NetworkInterfaceName
enP7782s1
readRate long: bits-per-second
6536
startTime long: millis
25842665640
writeRate long: bits-per-second
18232
networkInterface NetworkInterfaceName
enP8223s1
readRate long: bits-per-second
1312
startTime long: millis
98318055024
writeRate long: bits-per-second
20600

PhysicalMemory

default profiling startTime duration every chunk 11 17 21 25 26 27

Category: Operating System / Memory

OS Physical Memory

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

 *  PhysicalMemory event represents:
 *
 *  @totalSize == The amount of physical memory (hw) installed and reported by the OS, in bytes.
 *  @usedSize  == The amount of physical memory currently in use in the system (reserved/committed), in bytes.
 *
 *  Both fields are systemwide, i.e. represents the entire OS/HW environment.
 *  These fields do not include virtual memory.
 *
 *  If running inside a guest OS on top of a hypervisor in a virtualized environment,
 *  the total memory reported is the amount of memory configured for the guest OS by the hypervisor.
 */
TRACE_REQUEST_FUNC(PhysicalMemory) {
  u8 totalPhysicalMemory = os::physical_memory();
  EventPhysicalMemory event;
  event.set_totalSize(totalPhysicalMemory);
  event.set_usedSize(totalPhysicalMemory - os::available_memory());
  event.commit();
}

TRACE_REQUEST_FUNC(JavaThreadStatistics) {
  EventJavaThreadStatistics event;
  event.set_activeCount(ThreadService::get_live_thread_count());
  event.set_daemonCount(ThreadService::get_daemon_thread_count());
  event.set_accumulatedCount(ThreadService::get_total_thread_count());
  event.set_peakCount(ThreadService::get_peak_thread_count());

Configuration enabled period
default true everyChunk
profiling true everyChunk

Field Type Description
totalSize ulong: bytes Total Size Total amount of physical memory available to OS
usedSize ulong: bytes Used Size Total amount of physical memory in use

Examples 3
startTime long: millis
373398692
totalSize ulong: bytes
16766418944
usedSize ulong: bytes
1072386048
startTime long: millis
113943740137
totalSize ulong: bytes
16766418944
usedSize ulong: bytes
2230005760
startTime long: millis
99069123084
totalSize ulong: bytes
16766423040
usedSize ulong: bytes
5401505792

ContainerCPUThrottling

default profiling startTime duration stackTrace 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ContainerCPUThrottlingEvent.java

Category: Operating System / Processor

Container CPU throttling related information

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/ContainerCPUThrottlingEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "ContainerCPUThrottling")
@Label("CPU Throttling")
@Category({"Operating System", "Processor"})
@Description("Container CPU throttling related information")
public class ContainerCPUThrottlingEvent extends AbstractJDKEvent {
  @Label("CPU Elapsed Slices")
  @Description("Number of time-slice periods that have elapsed if a CPU quota has been setup for the container")
  public long cpuElapsedSlices;

  @Label("CPU Throttled Slices")
  @Description("Number of time-slice periods that the CPU has been throttled or limited due to exceeding CPU quota")
  public long cpuThrottledSlices;

  @Label("CPU Throttled Time")
  @Description("Total time duration, in nanoseconds, that the CPU has been throttled or limited due to exceeding CPU quota")
  @Timespan

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

            Logger.log(LogTag.JFR_SYSTEM, LogLevel.INFO, "Retransformed JDK classes");
            jvm.retransformClasses(list.toArray(new Class<?>[list.size()]));
        } catch (IllegalStateException ise) {
            throw ise;
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not add instrumentation for JDK events. " + e.getMessage());
        }
    }

    private static void initializeContainerEvents() {
        containerMetrics = Container.metrics();
        SecuritySupport.registerEvent(ContainerConfigurationEvent.class);
        SecuritySupport.registerEvent(ContainerCPUUsageEvent.class);
        SecuritySupport.registerEvent(ContainerCPUThrottlingEvent.class);
        SecuritySupport.registerEvent(ContainerMemoryUsageEvent.class);
        SecuritySupport.registerEvent(ContainerIOUsageEvent.class);

        RequestEngine.addTrustedJDKHook(ContainerConfigurationEvent.class, emitContainerConfiguration);
        RequestEngine.addTrustedJDKHook(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        RequestEngine.addTrustedJDKHook(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        RequestEngine.addTrustedJDKHook(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        RequestEngine.addTrustedJDKHook(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void emitExceptionStatistics() {
        ExceptionStatisticsEvent t = new ExceptionStatisticsEvent();
        t.throwables = ThrowableTracer.numThrowables();
        t.commit();
    }

    private static void emitContainerConfiguration() {

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

    private static void emitContainerIOUsage() {
        if (containerMetrics != null) {
            ContainerIOUsageEvent event = new ContainerIOUsageEvent();

            event.serviceRequests = containerMetrics.getBlkIOServiceCount();
            event.dataTransferred = containerMetrics.getBlkIOServiced();
            event.commit();
        }
    }

    private static void emitContainerCPUThrottling() {
        if (containerMetrics != null) {
            ContainerCPUThrottlingEvent event = new ContainerCPUThrottlingEvent();

            event.cpuElapsedSlices = containerMetrics.getCpuNumPeriods();
            event.cpuThrottledSlices = containerMetrics.getCpuNumThrottled();
            event.cpuThrottledTime = containerMetrics.getCpuThrottledTime();
            event.commit();
        }
    }

    @SuppressWarnings("deprecation")
    public static byte[] retransformCallback(Class<?> klass, byte[] oldBytes) throws Throwable {
        if (java.lang.Throwable.class == klass) {

Configuration enabled period
default true 30 s
profiling true 30 s

Field Type Description
cpuElapsedSlices long CPU Elapsed Slices Number of time-slice periods that have elapsed if a CPU quota has been setup for the container
cpuThrottledSlices long CPU Throttled Slices Number of time-slice periods that the CPU has been throttled or limited due to exceeding CPU quota
cpuThrottledTime long: nanos CPU Throttled Time Total time duration, in nanoseconds, that the CPU has been throttled or limited due to exceeding CPU quota

ProcessStart

default profiling startTime duration stackTrace 15 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ProcessStartEvent.java

Category: Operating System

Operating system process started

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/java.base/share/classes/jdk/internal/event/ProcessStartEvent.java:

package jdk.internal.event;

/**
 * Event for the start of an OS procsss
 */

public final class ProcessStartEvent extends Event {
    public long pid;
    public String directory;
    public String command;
}

src/java.base/share/classes/java/lang/ProcessBuilder.java:

        for (int i = 1; i < cmdarray.length; i++) {
            if (cmdarray[i].indexOf('\u0000') >= 0) {
                throw new IOException("invalid null character in command");
            }
        }

        try {
            Process process = ProcessImpl.start(cmdarray,
                                     environment,
                                     dir,
                                     redirects,
                                     redirectErrorStream);
            ProcessStartEvent event = new ProcessStartEvent();
            if (event.isEnabled()) {
                StringJoiner command = new StringJoiner(" ");
                for (String s: cmdarray) {
                    command.add(s);
                }
                event.directory = dir;
                event.command = command.toString();
                event.pid = process.pid();
                event.commit();
            }
            return process;

src/jdk.jfr/share/classes/jdk/jfr/events/ProcessStartEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.MirrorEvent;

@Category({"Operating System"})
@Label("Process Start")
@Name("jdk.ProcessStart")
@Description("Operating system process started")
@MirrorEvent(className = "jdk.internal.event.ProcessStartEvent")
public final class ProcessStartEvent extends AbstractJDKEvent {
    @Label("Process Id")
    public long pid;

    @Label("Directory")
    public String directory;

    @Label("Command")
    public String command;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

public final class JDKEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        TLSHandshakeEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class
    };

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,

Configuration enabled stackTrace
default true true
profiling true true

Field Type Description
pid long Process Id
directory string Directory
command string Command

Examples 3
command string
/sbin/ldconfig -p
directory string
null
pid long
3012
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
18
lineNumber int
1025
method Method
descriptor string
()Ljava/util/ArrayList;
hidden boolean
false
modifiers int
10
name string
getLinuxLdPaths
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
25.0.3
name string
java/net
hidden boolean
false
modifiers int
1
name string
com/sun/jna/NativeLibrary
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
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
com/sun/jna
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
29988536905
command string
setsid bash -c echo $$
directory string
null
pid long
3153
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
133
lineNumber int
998
method Method
descriptor string
()V
hidden boolean
false
modifiers int
2
name string
runCommand
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
25.0.3
name string
java/net
hidden boolean
false
modifiers int
1025
name string
org/apache/hadoop/util/Shell
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
25.0.3
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/hadoop/util
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
90494505323
command string
java -version
directory string
null
pid long
3319
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
27
lineNumber int
238
method Method
descriptor string
()V
hidden boolean
false
modifiers int
8
name string
startProcess
type Class
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/loader
hidden boolean
false
modifiers int
1
name string
jfr_sample/Main
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$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
25.0.3
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
1179010083

ContainerMemoryUsage

default profiling startTime duration stackTrace 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ContainerMemoryUsageEvent.java

Category: Operating System / Memory

Container memory usage related information

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/ContainerMemoryUsageEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "ContainerMemoryUsage")
@Label("Container Memory Usage")
@Category({"Operating System", "Memory"})
@Description("Container memory usage related information")
public final class ContainerMemoryUsageEvent extends AbstractJDKEvent {
    @Label("Memory Fail Count")
    @Description("Number of times that user memory requests in the container have exceeded the memory limit")
    public long memoryFailCount;

    @Label("Memory Usage")
    @Description("Amount of physical memory, in bytes, that is currently allocated in the current container")
    @DataAmount
    public long memoryUsage;

    @Label("Memory and Swap Usage")
    @Description("Amount of physical memory and swap space, in bytes, that is currently allocated in the current container")

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

            jvm.retransformClasses(list.toArray(new Class<?>[list.size()]));
        } catch (IllegalStateException ise) {
            throw ise;
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not add instrumentation for JDK events. " + e.getMessage());
        }
    }

    private static void initializeContainerEvents() {
        containerMetrics = Container.metrics();
        SecuritySupport.registerEvent(ContainerConfigurationEvent.class);
        SecuritySupport.registerEvent(ContainerCPUUsageEvent.class);
        SecuritySupport.registerEvent(ContainerCPUThrottlingEvent.class);
        SecuritySupport.registerEvent(ContainerMemoryUsageEvent.class);
        SecuritySupport.registerEvent(ContainerIOUsageEvent.class);

        RequestEngine.addTrustedJDKHook(ContainerConfigurationEvent.class, emitContainerConfiguration);
        RequestEngine.addTrustedJDKHook(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        RequestEngine.addTrustedJDKHook(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        RequestEngine.addTrustedJDKHook(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        RequestEngine.addTrustedJDKHook(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void emitExceptionStatistics() {
        ExceptionStatisticsEvent t = new ExceptionStatisticsEvent();
        t.throwables = ThrowableTracer.numThrowables();
        t.commit();
    }

    private static void emitContainerConfiguration() {
        if (containerMetrics != null) {

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

    private static void emitContainerCPUUsage() {
        if (containerMetrics != null) {
            ContainerCPUUsageEvent event = new ContainerCPUUsageEvent();

            event.cpuTime = containerMetrics.getCpuUsage();
            event.cpuSystemTime = containerMetrics.getCpuSystemUsage();
            event.cpuUserTime = containerMetrics.getCpuUserUsage();
            event.commit();
        }
    }
    private static void emitContainerMemoryUsage() {
        if (containerMetrics != null) {
            ContainerMemoryUsageEvent event = new ContainerMemoryUsageEvent();

            event.memoryFailCount = containerMetrics.getMemoryFailCount();
            event.memoryUsage = containerMetrics.getMemoryUsage();
            event.swapMemoryUsage = containerMetrics.getMemoryAndSwapUsage();
            event.commit();
        }
    }

    private static void emitContainerIOUsage() {
        if (containerMetrics != null) {
            ContainerIOUsageEvent event = new ContainerIOUsageEvent();

Configuration enabled period
default true 30 s
profiling true 30 s

Field Type Description
memoryFailCount long Memory Fail Count Number of times that user memory requests in the container have exceeded the memory limit
memoryUsage long: bytes Memory Usage Amount of physical memory, in bytes, that is currently allocated in the current container
swapMemoryUsage long: bytes Memory and Swap Usage Amount of physical memory and swap space, in bytes, that is currently allocated in the current container

ContainerCPUUsage

default profiling startTime duration stackTrace 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ContainerCPUUsageEvent.java

Category: Operating System / Processor

Container CPU usage related information

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/ContainerCPUUsageEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "ContainerCPUUsage")
@Label("CPU Usage")
@Category({"Operating System", "Processor"})
@Description("Container CPU usage related information")
public class ContainerCPUUsageEvent extends AbstractJDKEvent {
  @Label("CPU Time")
  @Description("Aggregate time consumed by all tasks in the container")
  @Timespan
  public long cpuTime;

  @Label("CPU User Time")
  @Description("Aggregate user time consumed by all tasks in the container")
  @Timespan
  public long cpuUserTime;

  @Label("CPU System Time")

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

            list.add(java.lang.Error.class);
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.INFO, "Retransformed JDK classes");
            jvm.retransformClasses(list.toArray(new Class<?>[list.size()]));
        } catch (IllegalStateException ise) {
            throw ise;
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not add instrumentation for JDK events. " + e.getMessage());
        }
    }

    private static void initializeContainerEvents() {
        containerMetrics = Container.metrics();
        SecuritySupport.registerEvent(ContainerConfigurationEvent.class);
        SecuritySupport.registerEvent(ContainerCPUUsageEvent.class);
        SecuritySupport.registerEvent(ContainerCPUThrottlingEvent.class);
        SecuritySupport.registerEvent(ContainerMemoryUsageEvent.class);
        SecuritySupport.registerEvent(ContainerIOUsageEvent.class);

        RequestEngine.addTrustedJDKHook(ContainerConfigurationEvent.class, emitContainerConfiguration);
        RequestEngine.addTrustedJDKHook(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        RequestEngine.addTrustedJDKHook(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        RequestEngine.addTrustedJDKHook(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        RequestEngine.addTrustedJDKHook(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void emitExceptionStatistics() {
        ExceptionStatisticsEvent t = new ExceptionStatisticsEvent();
        t.throwables = ThrowableTracer.numThrowables();
        t.commit();
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

            t.cpuSlicePeriod = containerMetrics.getCpuPeriod();
            t.cpuQuota = containerMetrics.getCpuQuota();
            t.cpuShares = containerMetrics.getCpuShares();
            t.effectiveCpuCount = containerMetrics.getEffectiveCpuCount();
            t.memorySoftLimit = containerMetrics.getMemorySoftLimit();
            t.memoryLimit = containerMetrics.getMemoryLimit();
            t.swapMemoryLimit = containerMetrics.getMemoryAndSwapLimit();
            t.commit();
        }
    }

    private static void emitContainerCPUUsage() {
        if (containerMetrics != null) {
            ContainerCPUUsageEvent event = new ContainerCPUUsageEvent();

            event.cpuTime = containerMetrics.getCpuUsage();
            event.cpuSystemTime = containerMetrics.getCpuSystemUsage();
            event.cpuUserTime = containerMetrics.getCpuUserUsage();
            event.commit();
        }
    }
    private static void emitContainerMemoryUsage() {
        if (containerMetrics != null) {
            ContainerMemoryUsageEvent event = new ContainerMemoryUsageEvent();

Configuration enabled period
default true 30 s
profiling true 30 s

Field Type Description
cpuTime long: nanos CPU Time Aggregate time consumed by all tasks in the container
cpuUserTime long: nanos CPU User Time Aggregate user time consumed by all tasks in the container
cpuSystemTime long: nanos CPU System Time Aggregate system time consumed by all tasks in the container

ContainerConfiguration

default profiling startTime duration stackTrace 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ContainerConfigurationEvent.java

Category: Operating System

A set of container specific attributes

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/ContainerConfigurationEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "ContainerConfiguration")
@Label("Container Configuration")
@Category({"Operating System"})
@Description("A set of container specific attributes")
public final class ContainerConfigurationEvent extends AbstractJDKEvent {
    @Label("Container Type")
    @Description("Container type information")
    public String containerType;

    @Label("CPU Slice Period")
    @Description("Length of the scheduling period for processes within the container")
    @Timespan(Timespan.MICROSECONDS)
    public long cpuSlicePeriod;

    @Label("CPU Quota")
    @Description("Total available run-time allowed during each scheduling period for all tasks in the container")

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

            list.add(java.lang.Throwable.class);
            list.add(java.lang.Error.class);
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.INFO, "Retransformed JDK classes");
            jvm.retransformClasses(list.toArray(new Class<?>[list.size()]));
        } catch (IllegalStateException ise) {
            throw ise;
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not add instrumentation for JDK events. " + e.getMessage());
        }
    }

    private static void initializeContainerEvents() {
        containerMetrics = Container.metrics();
        SecuritySupport.registerEvent(ContainerConfigurationEvent.class);
        SecuritySupport.registerEvent(ContainerCPUUsageEvent.class);
        SecuritySupport.registerEvent(ContainerCPUThrottlingEvent.class);
        SecuritySupport.registerEvent(ContainerMemoryUsageEvent.class);
        SecuritySupport.registerEvent(ContainerIOUsageEvent.class);

        RequestEngine.addTrustedJDKHook(ContainerConfigurationEvent.class, emitContainerConfiguration);
        RequestEngine.addTrustedJDKHook(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        RequestEngine.addTrustedJDKHook(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        RequestEngine.addTrustedJDKHook(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        RequestEngine.addTrustedJDKHook(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void emitExceptionStatistics() {
        ExceptionStatisticsEvent t = new ExceptionStatisticsEvent();
        t.throwables = ThrowableTracer.numThrowables();
        t.commit();
    }

    private static void emitContainerConfiguration() {
        if (containerMetrics != null) {
            ContainerConfigurationEvent t = new ContainerConfigurationEvent();
            t.containerType = containerMetrics.getProvider();
            t.cpuSlicePeriod = containerMetrics.getCpuPeriod();
            t.cpuQuota = containerMetrics.getCpuQuota();
            t.cpuShares = containerMetrics.getCpuShares();
            t.effectiveCpuCount = containerMetrics.getEffectiveCpuCount();
            t.memorySoftLimit = containerMetrics.getMemorySoftLimit();
            t.memoryLimit = containerMetrics.getMemoryLimit();
            t.swapMemoryLimit = containerMetrics.getMemoryAndSwapLimit();
            t.commit();
        }
    }

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
containerType string Container Type Container type information
cpuSlicePeriod long: microseconds CPU Slice Period Length of the scheduling period for processes within the container
cpuQuota long: microseconds CPU Quota Total available run-time allowed during each scheduling period for all tasks in the container
cpuShares long CPU Shares Relative weighting of processes with the container used for prioritizing the scheduling of processes across all containers running on a host
effectiveCpuCount long Effective CPU Count Number of effective processors that this container has available to it
memorySoftLimit long: bytes Memory Soft Limit Hint to the operating system that allows groups to specify the minimum required amount of physical memory
memoryLimit long: bytes Memory Limit Maximum amount of physical memory that can be allocated in the container
swapMemoryLimit long: bytes Memory and Swap Limit Maximum amount of physical memory and swap space, in bytes, that can be allocated in the container

ContainerIOUsage

default profiling startTime duration stackTrace 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ContainerIOUsageEvent.java

Category: Operating System / File System

Container IO usage related information

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/ContainerIOUsageEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "ContainerIOUsage")
@Label("Container IO Usage")
@Category({"Operating System", "File System"})
@Description("Container IO usage related information")
public class ContainerIOUsageEvent extends AbstractJDKEvent {

  @Label("Block IO Request Count")
  @Description("Number of block IO requests to the disk that have been issued by the container")
  public long serviceRequests;

  @Label("Block IO Transfer")
  @Description("Number of block IO bytes that have been transferred to/from the disk by the container")
  @DataAmount
  public long dataTransferred;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

        } catch (IllegalStateException ise) {
            throw ise;
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not add instrumentation for JDK events. " + e.getMessage());
        }
    }

    private static void initializeContainerEvents() {
        containerMetrics = Container.metrics();
        SecuritySupport.registerEvent(ContainerConfigurationEvent.class);
        SecuritySupport.registerEvent(ContainerCPUUsageEvent.class);
        SecuritySupport.registerEvent(ContainerCPUThrottlingEvent.class);
        SecuritySupport.registerEvent(ContainerMemoryUsageEvent.class);
        SecuritySupport.registerEvent(ContainerIOUsageEvent.class);

        RequestEngine.addTrustedJDKHook(ContainerConfigurationEvent.class, emitContainerConfiguration);
        RequestEngine.addTrustedJDKHook(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        RequestEngine.addTrustedJDKHook(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        RequestEngine.addTrustedJDKHook(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        RequestEngine.addTrustedJDKHook(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void emitExceptionStatistics() {
        ExceptionStatisticsEvent t = new ExceptionStatisticsEvent();
        t.throwables = ThrowableTracer.numThrowables();
        t.commit();
    }

    private static void emitContainerConfiguration() {
        if (containerMetrics != null) {
            ContainerConfigurationEvent t = new ContainerConfigurationEvent();

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

    private static void emitContainerMemoryUsage() {
        if (containerMetrics != null) {
            ContainerMemoryUsageEvent event = new ContainerMemoryUsageEvent();

            event.memoryFailCount = containerMetrics.getMemoryFailCount();
            event.memoryUsage = containerMetrics.getMemoryUsage();
            event.swapMemoryUsage = containerMetrics.getMemoryAndSwapUsage();
            event.commit();
        }
    }

    private static void emitContainerIOUsage() {
        if (containerMetrics != null) {
            ContainerIOUsageEvent event = new ContainerIOUsageEvent();

            event.serviceRequests = containerMetrics.getBlkIOServiceCount();
            event.dataTransferred = containerMetrics.getBlkIOServiced();
            event.commit();
        }
    }

    private static void emitContainerCPUThrottling() {
        if (containerMetrics != null) {
            ContainerCPUThrottlingEvent event = new ContainerCPUThrottlingEvent();

Configuration enabled period
default true 30 s
profiling true 30 s

Field Type Description
serviceRequests long Block IO Request Count Number of block IO requests to the disk that have been issued by the container
dataTransferred long: bytes Block IO Transfer Number of block IO bytes that have been transferred to/from the disk by the container

Types

Bytecode

14+

Bytecode Instruction

Field Type Description
bytecode string Instruction

Examples 3
invokeinterface
invokevirtual
invokeinterface

CalleeMethod

Field Type Description
type string Class
name string Method Name
descriptor string Method Descriptor

Examples 3
descriptor string
()Ljava/lang/String;
name string
getValue
type string
jdk/jfr/SettingControl
descriptor string
(Ljava/lang/String;)Ljava/lang/StringBuilder;
name string
append
type string
java/lang/StringBuilder
descriptor string
(Ljava/lang/Object;JB)V
name string
putByte
type string
jdk/internal/misc/Unsafe

ChunkHeader

14+

Chunk Header

Field Type Description
payload array byte Payload

Class

Java Class

Field Type Description
classLoader ClassLoader Class Loader
name Symbol Name
package Package Package
modifiers int Access Modifiers
hidden boolean 15+ Hidden

ClassLoader

Java Class Loader

Field Type Description
type Class Type
name Symbol Name

CodeBlobType

Code Blob Type

Field Type Description
type string Type

Examples 3
CodeHeap 'profiled nmethods'
CodeHeap 'non-profiled nmethods'
CodeHeap 'profiled nmethods'

CompilerPhaseType

Compiler Phase Type

Field Type Description
phase string Phase

Examples 3
After Iter GVN
Conservative coalescing
Fix up spills

CompilerType

14+

Compiler Type

Field Type Description
compiler string Compiler

Examples 3

CopyFailed

Field Type Description
objectCount ulong Object Count
firstSize ulong: bytes First Failed Object Size
smallestSize ulong: bytes Smallest Failed Object Size
totalSize ulong: bytes Total Object Size

DeoptimizationAction

14+

Deoptimization Action

Field Type Description
action string Action

Examples 3
maybe_recompile
maybe_recompile
maybe_recompile

DeoptimizationReason

14+

Deoptimization Reason

Field Type Description
reason string Reason

Examples 3
class_check
class_check
bimorphic_or_optimized_type_check

FlagValueOrigin

Flag Value Origin

Field Type Description
origin string Origin

Examples 3

FrameType

Frame type

Field Type Description
description string Description

Examples 3

G1EvacuationStatistics

Appearing in: linux_G1GC

Missing in: linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Field Type Description
gcId uint GC Identifier
allocated ulong: bytes Allocated Total memory allocated by PLABs
wasted ulong: bytes Wasted Total memory wasted within PLABs due to alignment or refill
used ulong: bytes Used Total memory occupied by objects within PLABs
undoWaste ulong: bytes Undo Wasted Total memory wasted due to allocation undo within PLABs
regionEndWaste ulong: bytes Region End Wasted Total memory wasted at the end of regions due to refill
regionsRefilled uint: 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
allocated ulong: bytes
3431968
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
6
regionEndWaste ulong: bytes
0
regionsRefilled uint: bytes
2
undoWaste ulong: bytes
0
used ulong: bytes
3056624
wasted ulong: bytes
32784
allocated ulong: bytes
8388608
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
109
regionEndWaste ulong: bytes
0
regionsRefilled uint: bytes
4
undoWaste ulong: bytes
0
used ulong: bytes
8388568
wasted ulong: bytes
40
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
128
regionEndWaste ulong: bytes
0
regionsRefilled uint: bytes
0
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0

G1HeapRegionType

Appearing in: linux_G1GC

Missing in: linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

G1 Heap Region Type

Field Type Description
type string Type

Examples 3

G1YCType

Appearing in: linux_G1GC

Missing in: linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

G1 YC Type

Field Type Description
type string Type

Examples 2
Normal
Concurrent Start

GCCause

GC Cause

Field Type Description
cause string Cause

Examples 3
System.gc()
G1 Evacuation Pause
Allocation Failure

GCName

GC Name

Field Type Description
name string Name

Examples 3

GCThresholdUpdater

GC Threshold Updater

Field Type Description
updater string Updater

Examples 3
compute_new_size
compute_new_size
compute_new_size

GCWhen

GC When

Field Type Description
when string When

Examples 3

InflateCause

Inflation Cause

Field Type Description
cause string Cause

Examples 3
Monitor Enter
VM Internal
Monitor Wait

MetadataType

Metadata Type

Field Type Description
type string Type

Examples 3

MetaspaceObjectType

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ZGC

Missing in: linux_ShenandoahGC

Metaspace Object Type

Field Type Description
type string Type

Examples 3
ConstantPool
ConstantPool
TypeArrayU8

MetaspaceSizes

Field Type Description
committed ulong: bytes Committed Committed memory for this space
used ulong: bytes Used Bytes allocated by objects in the space
reserved ulong: bytes Reserved Reserved memory for this space

Examples 3
committed ulong: bytes
26345472
reserved ulong: bytes
67108864
used ulong: bytes
26126520
committed ulong: bytes
32702464
reserved ulong: bytes
1140850688
used ulong: bytes
32350432
committed ulong: bytes
6356992
reserved ulong: bytes
1073741824
used ulong: bytes
6223912

Method

Java Method

Field Type Description
type Class Type
name Symbol Name
descriptor Symbol Descriptor
modifiers int Access Modifiers
hidden boolean Hidden

Module

Module

Field Type Description
name Symbol Name
version Symbol Version
location Symbol Location
classLoader ClassLoader Class Loader

NarrowOopMode

Narrow Oop Mode

Field Type Description
mode string Mode

Examples 3

NetworkInterfaceName

Network Interface

Field Type Description
networkInterface string Network Interface Network Interface Name

Examples 3

ObjectSpace

Appearing in: linux_ParallelGC

Missing in: linux_G1GC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Field Type Description
start ulong: address Start Address Start address of the space
end ulong: address End Address End address of the space
used ulong: bytes Used Bytes allocated by objects in the space
size ulong: bytes Size Size of the space

Examples 3
end ulong: address
33093058560
size ulong: bytes
130023424
start ulong: address
32963035136
used ulong: bytes
0
end ulong: address
30343692288
size ulong: bytes
176160768
start ulong: address
30167531520
used ulong: bytes
71483952
end ulong: address
33103544320
size ulong: bytes
10485760
start ulong: address
33093058560
used ulong: bytes
0

OldObject

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ZGC

Missing in: linux_ShenandoahGC

Old Object

Field Type Description
address ulong: address Memory Address
type Class Java Class
description string Object Description Object description
referrer Reference Referrer Object Object referencing this object

Examples 3
address ulong: address
30245886360
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/invoke/MethodType
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang/invoke
address ulong: address
30173450728
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
address ulong: address
30184347728
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/String
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang

OldObjectArray

Old Object Array

Field Type Description
size int Array Size Size of array
index int Index Index in the array

OldObjectField

Old Object Field

Field Type Description
name string Field Name of field
modifiers short Field Modifiers Field modifiers

OldObjectGcRoot

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ZGC

Missing in: linux_ShenandoahGC

GC Root

Field Type Description
description string Root Description Root information
system OldObjectRootSystem System The subsystem of origin for the root
type OldObjectRootType Type The root type

Examples 3

OldObjectRootSystem

GC Root System

Field Type Description
system string System

OldObjectRootType

GC Root Type

Field Type Description
type string Type

Package

Package

Field Type Description
name Symbol Name
module Module Module
exported boolean Exported

Reference

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ZGC

Missing in: linux_ShenandoahGC

Reference

Field Type Description
array OldObjectArray Array Information Array or null if it is not an array
field OldObjectField Field Information Field or null if it is an array
object OldObject Object Object holder for this reference
skip int Skip Value The object is this many hops away

Examples 3

ReferenceType

Reference Type

Field Type Description
type string Type

Examples 3
Weak reference
Final reference
Final reference

ShenandoahHeapRegionState

Appearing in: linux_ShenandoahGC

Missing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ZGC

Shenandoah Heap Region State

Field Type Description
state string State

Examples 2

StackFrame

Field Type Description
method Method Java Method
lineNumber int Line Number
bytecodeIndex int Bytecode Index
type FrameType Frame Type

Examples 3
bytecodeIndex int
7
lineNumber int
760
method Method
descriptor string
([BII)Ljava/lang/String;
hidden boolean
false
modifiers int
9
name string
newString
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
16
name string
java/lang/StringLatin1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
type FrameType
Inlined
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Z)[Ljava/lang/reflect/Method;
hidden boolean
false
modifiers int
258
name string
getDeclaredMethods0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Class
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
type FrameType
Native
bytecodeIndex int
9
lineNumber int
58
method Method
descriptor string
()Ljava/lang/System$Logger$Level;
hidden boolean
false
modifiers int
8
name string
getDefaultLevel
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
jdk/internal/logger/SimpleConsoleLogger
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/logger
type FrameType
Interpreted

StackTrace

Stacktrace

Field Type Description
truncated boolean Truncated
frames array StackFrame struct Stack Frames

Symbol

Symbol

Field Type Description
string string String

Examples 3
file:///home/runner/work/jfrevents/jfrevents/harness-140602-2306766489842645582/neo4j/lib/jna-5.13.0.jar
file:///home/runner/work/jfrevents/jfrevents/harness-140614-780637367523948717/twitter-finagle/lib/netty-buffer-4.1.99.Final.jar
file:///home/runner/work/jfrevents/jfrevents/harness-140629-9485767527491855067/twitter-finagle/lib/netty-buffer-4.1.99.Final.jar

Thread

Thread

Field Type Description
osName string OS Thread Name
osThreadId long OS Thread Id
javaName string Java Thread Name
javaThreadId long Java Thread Id
group ThreadGroup Java Thread Group

ThreadGroup

Thread Group

Field Type Description
parent ThreadGroup Parent
name string Name

Examples 3
null
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
name string
system
parent ThreadGroup
null

ThreadState

Java Thread State

Field Type Description
name string Name

Examples 3
STATE_RUNNABLE
STATE_RUNNABLE
STATE_RUNNABLE

VMOperationType

VM Operation Type

Field Type Description
type string Type

Examples 3
G1CollectForAllocation
CollectForMetadataAllocation
CollectForMetadataAllocation

VirtualSpace

Field Type Description
start ulong: address Start Address Start address of the virtual space
committedEnd ulong: address Committed End Address End address of the committed memory for the virtual space
committedSize ulong: bytes Committed Size Size of the committed memory for the virtual space
reservedEnd ulong: address Reserved End Address End address of the reserved memory for the virtual space
reservedSize ulong: bytes Reserved Size Size of the reserved memory for the virtual space

Examples 3
committedEnd ulong: address
30196891648
committedSize ulong: bytes
29360128
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
committedEnd ulong: address
30272389120
committedSize ulong: bytes
104857600
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
committedEnd ulong: address
31792824320
committedSize ulong: bytes
1625292800
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520

ZPageTypeType

15+

Appearing in: linux_ZGC

Missing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Z Page Type

Field Type Description
type string Type

Examples 2

ZStatisticsCounterType

Appearing in: linux_ZGC

Missing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Z Statistics Counter

Field Type Description
counter string Counter

Examples 1
Allocation Rate

ZStatisticsSamplerType

Appearing in: linux_ZGC

Missing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC

Z Statistics Sampler

Field Type Description
sampler string Sampler

Examples 2
Concurrent Remap Remembered
Concurrent Roots JavaThreads

XML Content Types

address

Annotation: jdk.jfr.MemoryAddress

Examples 3
140681343401984
140681368375296
140680850571264

bits-per-second

Annotation: jdk.jfr.DataAmount(BITS), jdk.jfr.Frequency

Examples 3

bytes

Annotation: jdk.jfr.DataAmount(BYTES)

Examples 3

bytes-per-second

Appearing in: linux_G1GC

Missing in: linux_ParallelGC, linux_SerialGC, linux_ShenandoahGC, linux_ZGC

Annotation: jdk.jfr.DataAmount(BYTES), jdk.jfr.Frequency

Examples 3
4.3104568865833527E8
0.0
1.5829618055923047E9

certificateId

Annotation: jdk.jfr.events.CertificateId

Examples 3
3406046841
657172038
2494060369

epochmillis

Annotation: jdk.jfr.Timestamp(MILLISECONDS_SINCE_EPOCH)

Examples 3
1780495574039
1780495574399
-9223372036854775808

hertz

Annotation: jdk.jfr.Frequency

Examples 3
6067.0127
1000000000
1000000000

microseconds

17+

Annotation: jdk.jfr.Timespan(MICROSECONDS)

millis

Annotation: jdk.jfr.Timespan(MILLISECONDS)

Examples 3
1000
374409948
9223372036854775807

nanos

Annotation: jdk.jfr.Timespan(NANOSECONDS)

Examples 3
1000000
-9223372036854775808
-9223372036854775808

percentage

Annotation: jdk.jfr.Percentage

Examples 3
0.89873415
0.017721519
0.9265823

tickspan

Annotation: jdk.jfr.Timespan(TICKS)

Examples 3

tickstamp

Annotation: jdk.jfr.Timestamp(TICKS)

XML Types

Class

Parameter Type const Klass*
Field Type const Klass*
Java Type java.lang.Class
Examples 3
null
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
16
name string
jdk/jfr/internal/Control
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
25.0.3
name string
jdk/jfr/internal
null

ClassLoader

Parameter Type const ClassLoaderData*
Field Type const ClassLoaderData*
Examples 3
name string
bootstrap
type Class
null
name string
bootstrap
type Class
null
name string
bootstrap
type Class
null

Method

Parameter Type const Method*
Field Type const Method*
Examples 3
descriptor string
(Ljava/lang/String;)V
hidden boolean
false
modifiers int
1
name string
setValue
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
16
name string
jdk/jfr/internal/Control
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
25.0.3
name string
jdk/jfr/internal
descriptor string
()Ljava/lang/System$Logger$Level;
hidden boolean
false
modifiers int
8
name string
getDefaultLevel
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
jdk/internal/logger/SimpleConsoleLogger
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/logger
descriptor string
(Ljava/util/regex/Matcher;ILjava/lang/CharSequence;)Z
hidden boolean
false
modifiers int
0
name string
match
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
24
name string
java/util/regex/Pattern$BmpCharPropertyGreedy
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util/regex

Module

Parameter Type const ModuleEntry*
Field Type const ModuleEntry*
Examples 3
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.jfr
name string
jdk.jfr
version string
25.0.3
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.jfr
name string
jdk.jfr
version string
25.0.3
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3

Package

Parameter Type const PackageEntry*
Field Type const PackageEntry*
Examples 3
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/util/regex
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.jfr
name string
jdk.jfr
version string
25.0.3
name string
jdk/jfr/internal

StackTrace

15+

Parameter Type u8
Field Type u8
Java Type jdk.types.StackTrace
Examples 3
frames StackFrame
bytecodeIndex int
7
lineNumber int
760
method Method
descriptor string
([BII)Ljava/lang/String;
hidden boolean
false
modifiers int
9
name string
newString
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
16
name string
java/lang/StringLatin1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
type FrameType
Inlined
truncated boolean
false
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Z)[Ljava/lang/reflect/Method;
hidden boolean
false
modifiers int
258
name string
getDeclaredMethods0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/Class
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
java/lang
type FrameType
Native
truncated boolean
false
frames StackFrame
bytecodeIndex int
9
lineNumber int
58
method Method
descriptor string
()Ljava/lang/System$Logger$Level;
hidden boolean
false
modifiers int
8
name string
getDefaultLevel
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
jdk/internal/logger/SimpleConsoleLogger
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
25.0.3
name string
jdk/internal/logger
type FrameType
Interpreted
truncated boolean
false

Thread

Parameter Type u8
Field Type u8
Java Type java.lang.Thread
Examples 3
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-13
javaThreadId long
64
osName string
UCT-akka.actor.default-dispatcher-13
osThreadId long
2841
virtual boolean
false
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-10
javaThreadId long
119
osName string
UCT-akka.actor.default-dispatcher-10
osThreadId long
2893
virtual boolean
false
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-8
javaThreadId long
56
osName string
UCT-akka.actor.default-dispatcher-8
osThreadId long
2833
virtual boolean
false

Ticks

unsigned

Appearing in: linux_G1GC, linux_ParallelGC, linux_SerialGC, linux_ZGC

Missing in: linux_ShenandoahGC

Parameter Type const Ticks&
Field Type Ticks
Java Type long
Content Type tickstamp
Examples 3
47254146138
25399055860
34487343876

Tickspan

unsigned

Parameter Type const Tickspan&
Field Type Tickspan
Java Type long
Content Type tickspan

boolean

Parameter Type bool
Field Type bool
Java Type boolean
Examples 3

byte

Parameter Type s1
Field Type s1
Java Type byte

char

Parameter Type char
Field Type char
Java Type char

double

Parameter Type double
Field Type double
Java Type double
Examples 3

float

Parameter Type float
Field Type float
Java Type float
Examples 3
2.5820923
2.5779777
1.6056082

int

Parameter Type s4
Field Type s4
Java Type int
Examples 3

long

Parameter Type s8
Field Type s8
Java Type long
Examples 3

short

Parameter Type s2
Field Type s2
Java Type short

string

Parameter Type const char*
Field Type const char*
Java Type java.lang.String
Examples 3
/home/runner/work/jfrevents/jfrevents/jfr/sample_linux_UseG1GC.jfr
1
threshold

ubyte

unsigned

Parameter Type u1
Field Type u1
Java Type byte
Examples 3

uint

unsigned

Parameter Type unsigned
Field Type unsigned
Java Type int
Examples 3

ulong

unsigned

Parameter Type u8
Field Type u8
Java Type long
Examples 3

ushort

unsigned

Parameter Type u2
Field Type u2
Java Type short
Examples 3