Introduction

The following are the events for OpenJDK 22 (jdk-22.0.2+9, permalink, 22-February-2026), and Graal VM 24.0.2 (jdk-22.0.2) . The events are collected from the event configuration and the source code. Visit the jfreventcollector repository for more information. This is also the place you can contribute additional event descriptions, if you don't want to contribute them directly to the OpenJDK. The site generator lives on GitHub, too.

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

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

Flight Recorder

DumpReason

profiling default startTime 11 17 21 25 26 27

Category: Flight Recorder

Who requested the recording and why

Code Context

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

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

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

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

Configuration enabled
profiling true
default true

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

DataLoss

profiling default startTime 11 17 21 25 26 27 graal vm

Category: Flight Recorder

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

Code Context

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

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

JVM_ENTRY_NO_ENV(jlong, jfr_host_total_memory(JNIEnv* env, jclass jvm))
#ifdef LINUX
  // We want the host memory, not the container limit.
  // os::physical_memory() would return the container limit.
  return os::Linux::physical_memory();
#else
  return os::physical_memory();
#endif
JVM_END

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

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

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

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

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

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

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

Configuration enabled
profiling true
default true

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

Flush

experimental startTime duration 14 17 21 25 26 27

Category: Flight Recorder

Code Context

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

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

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

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

class StackTraceRepository : public StackObj {
 private:

Configuration enabled threshold
profiling false 0 ns
default false 0 ns

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

Examples 3
elements ulong
1389
flushId ulong
274
size ulong: bytes
277222
startTime long: millis
387461911035
elements ulong
2123
flushId ulong
203
size ulong: bytes
460527
startTime long: millis
398381932714
elements ulong
3569
flushId ulong
174
size ulong: bytes
1143203
startTime long: millis
367229007438

ActiveRecording

profiling default startTime duration stackTrace 11 17 21 25 26 27

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

Category: Flight Recorder

Code Context

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

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

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

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

    @Label("Id")
    public long id;

    @Label("Name")
    public String name;

    @Label("Destination")

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

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

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

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

public final class JDKEvents {

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

Configuration enabled
profiling true
default true

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

Examples 3
destination string
/home/runner/work/jfrevents/jfrevents/jfr/sample_UseG1GC.jfr
disk boolean
true
flushInterval long: millis
1000
id long
1
maxAge long: millis
9223372036854775807
maxSize long: bytes
262144000
name string
1
recordingDuration long: millis
9223372036854775807
recordingStart long: epochmillis
1771720994247
stackTrace StackTrace
null
startTime long: millis
387244211012
destination string
/home/runner/work/jfrevents/jfrevents/jfr/sample_UseParallelGC.jfr
disk boolean
true
flushInterval long: millis
1000
id long
1
maxAge long: millis
9223372036854775807
maxSize long: bytes
262144000
name string
1
recordingDuration long: millis
9223372036854775807
recordingStart long: epochmillis
1771720993815
stackTrace StackTrace
null
startTime long: millis
451229306601
destination string
/home/runner/work/jfrevents/jfrevents/jfr/sample_UseSerialGC.jfr
disk boolean
true
flushInterval long: millis
1000
id long
1
maxAge long: millis
9223372036854775807
maxSize long: bytes
262144000
name string
1
recordingDuration long: millis
9223372036854775807
recordingStart long: epochmillis
1771721007066
stackTrace StackTrace
null
startTime long: millis
472617687045

ActiveSetting

profiling default startTime duration stackTrace 11 17 21 25 26 27

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

Category: Flight Recorder

Code Context

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

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

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

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

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

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

    @Label("Setting Value")

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

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

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

    public PlatformEventType getEventType() {
        return type;

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

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

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

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

public final class JDKEvents {

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

Configuration enabled
profiling true
default true

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

Examples 3
id long
21
name string
stackTrace
stackTrace StackTrace
null
startTime long: millis
398043285082
value string
true
id long
19
name string
enabled
stackTrace StackTrace
null
startTime long: millis
296982034566
value string
true
id long
56
name string
enabled
stackTrace StackTrace
null
startTime long: millis
351476198762
value string
true

JVM

JVMInformation

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

Category: Java Virtual Machine

Description of JVM and the Java application

Code Context

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

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

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

TRACE_REQUEST_FUNC(ResidentSetSize) {
  os::jfr_report_memory_info();
}

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

TRACE_REQUEST_FUNC(OSInformation) {

Configuration enabled period
profiling true beginChunk
default true beginChunk

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

Examples 3
javaArguments string
/home/runner/work/jfrevents/jfrevents/.cache/renaissance.jar -t 5 -r 1 all
jvmArguments string
-XX:StartFlightRecording=filename=/home/runner/work/jfrevents/jfrevents/jfr/sample_UseG1GC.jfr,settings=/home/runner/work/jfrevents/jfrevents/.cache/jfc.jfc -XX:+UseG1GC
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1771720993806
jvmVersion string
OpenJDK 64-Bit Server VM (21.0.10.0.1+1-LTS) for linux-amd64 JRE (21.0.10.0.1+1-LTS), built on 2026-02-17T05:46:25Z by "jenkinsi" with gcc 11.3.0
pid long
2319
startTime long: millis
304467154761
javaArguments string
/home/runner/work/jfrevents/jfrevents/.cache/renaissance.jar -t 5 -r 1 all
jvmArguments string
-XX:StartFlightRecording=filename=/home/runner/work/jfrevents/jfrevents/jfr/sample_UseParallelGC.jfr,settings=/home/runner/work/jfrevents/jfrevents/.cache/jfc.jfc -XX:+UseParallelGC
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1771720993410
jvmVersion string
OpenJDK 64-Bit Server VM (21.0.10.0.1+1-LTS) for linux-amd64 JRE (21.0.10.0.1+1-LTS), built on 2026-02-17T05:46:25Z by "jenkinsi" with gcc 11.3.0
pid long
2294
startTime long: millis
377586501655
javaArguments string
/home/runner/work/jfrevents/jfrevents/.cache/renaissance.jar -t 5 -r 1 all
jvmArguments string
-XX:StartFlightRecording=filename=/home/runner/work/jfrevents/jfrevents/jfr/sample_UseSerialGC.jfr,settings=/home/runner/work/jfrevents/jfrevents/.cache/jfc.jfc -XX:+UseSerialGC
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1771721006649
jvmVersion string
OpenJDK 64-Bit Server VM (21.0.10.0.1+1-LTS) for linux-amd64 JRE (21.0.10.0.1+1-LTS), built on 2026-02-17T05:46:25Z by "jenkinsi" with gcc 11.3.0
pid long
2318
startTime long: millis
399929709678

InitialSystemProperty

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

Category: Java Virtual Machine

System Property at JVM start

Code Context

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

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

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

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

TRACE_REQUEST_FUNC(ThreadAllocationStatistics) {

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
key string Key
value string Value

Examples 3
key string
java.class.path
startTime long: millis
351480057407
value string
/home/runner/work/jfrevents/jfrevents/.cache/renaissance.jar
key string
java.vm.specification.vendor
startTime long: millis
398047142339
value string
Oracle Corporation
key string
java.library.path
startTime long: millis
314692125127
value string
/usr/java/packages/lib:/usr/lib64:/lib64:/lib:/usr/lib

JVM: Class Loading

ClassLoad

startTime duration eventThread stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / Class Loading

Code Context

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

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

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

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

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

 public:

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

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

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

protected:
  // Used by SystemDictionaryShared

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

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

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

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

// 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 != nullptr && !Signature::is_array(name) &&
         !Signature::has_envelope(name), "invalid class name");

  EventClassLoad class_load_start_event;

  HandleMark hm(THREAD);

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

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

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

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

  EventClassLoad class_load_start_event;
  ClassLoaderData* loader_data;

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

  assert(st != nullptr, "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 == nullptr) {
    return nullptr;
  }

  // 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;

  // Add to class hierarchy, and do possible deoptimizations.
  loaded_lambda->add_to_hierarchy(THREAD);
  // 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);
  }
  if (class_load_start_event.should_commit()) {

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

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

Examples 3
definingClassLoader ClassLoader
null
initiatingClassLoader ClassLoader
null
loadedClass Class
classLoader ClassLoader
null
hidden boolean
true
modifiers int
16
name string
java.lang.invoke.LambdaForm$MH/0x00007fd828422000
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang/invoke
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/Class;Ljava/lang/String;[BIILjava/security/ProtectionDomain;ZILjava/lang/Object;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Native
truncated boolean
true
startTime long: millis
353892221806
definingClassLoader ClassLoader
null
initiatingClassLoader ClassLoader
null
loadedClass Class
classLoader ClassLoader
null
hidden boolean
true
modifiers int
16
name string
java.lang.invoke.LambdaForm$MH/0x00007f9fdd428800
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang/invoke
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
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method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/Class;Ljava/lang/String;[BIILjava/security/ProtectionDomain;ZILjava/lang/Object;)Ljava/lang/Class;
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264
name string
defineClass0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
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java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
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truncated boolean
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startTime long: millis
428965742889
definingClassLoader ClassLoader
null
initiatingClassLoader ClassLoader
null
loadedClass Class
classLoader ClassLoader
null
hidden boolean
true
modifiers int
16
name string
java.lang.invoke.LambdaForm$MH/0x00007fceb541b800
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang/invoke
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
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lineNumber int
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method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/Class;Ljava/lang/String;[BIILjava/security/ProtectionDomain;ZILjava/lang/Object;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
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modifiers int
1025
name string
java/lang/ClassLoader
package Package
exported boolean
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module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Native
truncated boolean
true
startTime long: millis
299253814205

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:

    // before references to the initiating class loader.
    loader_data->record_dependency(loaded_class);

    update_dictionary(THREAD, loaded_class, loader_data);

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

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

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

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

Configuration enabled stackTrace
profiling false true
default false true

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

Examples 3
definedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
1537
name string
scala/reflect/internal/FreshNames
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/reflect/internal
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/String;[BIILjava/security/ProtectionDomain;Ljava/lang/String;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass1
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
455351421203
definedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
org/apache/spark/sql/SQLImplicits$$typecreator1$12
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/sql
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/String;[BIILjava/security/ProtectionDomain;Ljava/lang/String;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass1
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
334962812465
definedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
1537
name string
scala/reflect/runtime/JavaMirrors
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/reflect/runtime
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/String;[BIILjava/security/ProtectionDomain;Ljava/lang/String;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass1
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
413371402286

ClassRedefinition

profiling default startTime 15 17 21 25 26 27

Category: Java Virtual Machine / Class Loading

Code Context

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

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

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

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

  increment_class_counter(the_class);

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

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

Configuration enabled
profiling true
default true

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

RedefineClasses

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

Category: Java Virtual Machine / Class Loading

Code Context

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

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

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


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

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

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

RetransformClasses

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

Category: Java Virtual Machine / Class Loading

Code Context

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

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

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

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

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

ClassUnload

startTime eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Class Loading

Code Context

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

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

  ClassLoadingService::notify_class_unloaded(ik);

  SystemDictionaryShared::handle_class_unloading(ik);

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

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

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

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

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

Configuration enabled
profiling false
default false

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

Examples 3
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
startTime long: millis
306847408288
unloadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
true
modifiers int
4112
name string
scala.concurrent.Future$$$Lambda/0x00007fceb0b5f068
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/concurrent
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
startTime long: millis
465677176776
unloadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
1537
name string
scala/collection/immutable/StrictOptimizedMapOps
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection/immutable
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
startTime long: millis
425285366143
unloadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
scala/collection/immutable/BitmapIndexedMapNode
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection/immutable

JVM: Code Cache

CodeCacheFull

profiling default startTime eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Code Cache

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

Code Context

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

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

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

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

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

Configuration enabled
profiling true
default true

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

CodeCacheStatistics

profiling default startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Code Cache

Code Context

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

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

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

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

Configuration enabled period
profiling true everyChunk
default true everyChunk

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

Examples 3
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'non-profiled nmethods'
entryCount int
7357
fullCount int
0
methodCount int
7357
reservedTopAddress ulong: address
140527429222400
startAddress ulong: address
140527306309632
startTime long: millis
311710891600
unallocatedCapacity ulong: bytes
109065728
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'non-profiled nmethods'
entryCount int
7638
fullCount int
0
methodCount int
7638
reservedTopAddress ulong: address
140325834194944
startAddress ulong: address
140325711282176
startTime long: millis
401576577173
unallocatedCapacity ulong: bytes
109754240
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'profiled nmethods'
entryCount int
9389
fullCount int
0
methodCount int
9389
reservedTopAddress ulong: address
140567700008960
startAddress ulong: address
140567577100288
startTime long: millis
431684184214
unallocatedCapacity ulong: bytes
94907648

CodeCacheConfiguration

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

Category: Java Virtual Machine / Code Cache

Code Context

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

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

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

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

Configuration enabled period
profiling true beginChunk
default true beginChunk

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

Examples 3
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
5832780
nonProfiledSize ulong: bytes
122912730
profiledSize ulong: bytes
122912730
reservedSize ulong: bytes
251658240
reservedTopAddress ulong: address
140325834194944
startAddress ulong: address
140325582536704
startTime long: millis
451934234922
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
5832780
nonProfiledSize ulong: bytes
122912730
profiledSize ulong: bytes
122912730
reservedSize ulong: bytes
251658240
reservedTopAddress ulong: address
140567828758528
startAddress ulong: address
140567577100288
startTime long: millis
403214738507
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
5832780
nonProfiledSize ulong: bytes
122912730
profiledSize ulong: bytes
122912730
reservedSize ulong: bytes
251658240
reservedTopAddress ulong: address
140527429222400
startAddress ulong: address
140527177564160
startTime long: millis
378343600612

JVM: Compiler

JITRestart

profiling default startTime eventThread 17 21 25 26 27

Category: Java Virtual Machine / Compiler

Restart of the JIT compilers after they were stopped

Code Context

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

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

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

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

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

uint8_t CodeCache::_unloading_cycle = 1;

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

Configuration enabled
profiling true
default true

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

Compilation

profiling default startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Compiler

Results of method compilation attempts

Code Context

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

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

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

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

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 = nullptr;
  bool failure_reason_on_C_heap = false;
  const char* retry_message = nullptr;

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

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

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

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

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

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

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

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

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

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

  class PhaseEvent : AllStatic {
    friend class CompilerPhaseTypeConstant;
   public:

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

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

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

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

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

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

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

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

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

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

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

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

        void setCompileId(int compileId);

        void setCompileLevel(int compileLevel);

        void setSucceeded(boolean succeeded);

Configuration enabled threshold
profiling true 100 ms
default true 1000 ms

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

Examples 3
codeSize ulong: bytes
1608
compileId int
85153
compileLevel ushort
3
compiler CompilerType
c1
inlinedBytes ulong: bytes
47
isOsr boolean
false
method Method
descriptor string
()Ljava/lang/Object;
hidden boolean
false
modifiers int
1
name string
writeReplace
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
breeze/linalg/DenseVector
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
breeze/linalg
startTime long: millis
442685772876
succeded boolean
true
codeSize ulong: bytes
1248
compileId int
74151
compileLevel ushort
3
compiler CompilerType
c1
inlinedBytes ulong: bytes
32
isOsr boolean
false
method Method
descriptor string
(JLscala/Enumeration$Value;Ljava/nio/ByteBuffer;)V
hidden boolean
false
modifiers int
1
name string
statusUpdate
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/scheduler/local/LocalSchedulerBackend
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/scheduler/local
startTime long: millis
302621573723
succeded boolean
true
codeSize ulong: bytes
152312
compileId int
94199
compileLevel ushort
4
compiler CompilerType
c2
inlinedBytes ulong: bytes
6077
isOsr boolean
false
method Method
descriptor string
(Ldotty/tools/dotc/ast/Trees$Tree;Ldotty/tools/dotc/core/Contexts$Context;)Ldotty/tools/dotc/ast/Trees$Tree;
hidden boolean
false
modifiers int
1
name string
transform
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
dotty/tools/dotc/transform/PostTyper$PostTyperTransformer
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
dotty/tools/dotc/transform
startTime long: millis
492676850609
succeded boolean
true

CompilerPhase

profiling default startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Compiler

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

Code Context

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

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

C2V_END

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_END

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_END

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

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

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

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

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

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

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

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

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

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

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

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

  class CompilationEvent : AllStatic {
   public:

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

  class PhaseEvent : AllStatic {
    friend class CompilerPhaseTypeConstant;
   public:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Configuration enabled threshold
profiling true 10 s
default true 60 s

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

CompilationFailure

profiling startTime eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Compiler

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

Code Context

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

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

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

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

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

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

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

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

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

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

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

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

  class PhaseEvent : AllStatic {
    friend class CompilerPhaseTypeConstant;
   public:

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

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

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

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

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

Configuration enabled
profiling true
default false

Field Type Description
failureMessage string Failure Message
compileId int Compilation Identifier

Examples 3
compileId int
99213
failureMessage string
retry without subsuming loads
startTime long: millis
497796311703
compileId int
93776
failureMessage string
retry without subsuming loads
startTime long: millis
370469244151
compileId int
92593
failureMessage string
retry without subsuming loads
startTime long: millis
452846828130

CompilerInlining

startTime eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / Compiler / Optimization

Describes the result of a method inlining attempt

Code Context

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

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

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

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

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

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

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

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

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

#else
  return -1;
#endif // !INCLUDE_JFR
C2V_END

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_END

C2V_VMENTRY(void, notifyCompilerInliningEvent, (JNIEnv* env, jobject, jint compileId, ARGUMENT_PAIR(caller), ARGUMENT_PAIR(callee), jboolean succeeded, jstring jmessage, jint bci))
  EventCompilerInlining event;
  if (event.should_commit()) {
    Method* caller = UNPACK_PAIR(Method, caller);
    Method* callee = UNPACK_PAIR(Method, callee);
    JVMCIObject message = JVMCIENV->wrap(jmessage);
    CompilerEvent::InlineEvent::post(event, compileId, caller, callee, succeeded, JVMCIENV->as_utf8_string(message), bci);
  }
C2V_END

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Configuration enabled
profiling false
default false

Field Type Description
compileId int 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
6
callee CalleeMethod
descriptor string
(Lscala/collection/Iterator;Lscala/Function0;)V
name string
<init>
type string
org/apache/spark/util/CompletionIterator$$anon$1
caller Method
descriptor string
(Lscala/collection/Iterator;Lscala/Function0;)Lorg/apache/spark/util/CompletionIterator;
hidden boolean
false
modifiers int
1
name string
apply
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
org/apache/spark/util/CompletionIterator$
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/util
compileId int
72655
message string
inline
startTime long: millis
351479277603
succeeded boolean
true
bci int
39
callee CalleeMethod
descriptor string
(I)Ljava/lang/StringBuilder;
name string
append
type string
java/lang/StringBuilder
caller Method
descriptor string
(I)Ljava/lang/Object;
hidden boolean
false
modifiers int
1
name string
remove
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
scala/collection/mutable/ArrayBuffer
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection/mutable
compileId int
73844
message string
inline
startTime long: millis
298681172931
succeeded boolean
true
bci int
17
callee CalleeMethod
descriptor string
(Lscala/Function1;)Lscala/Option;
name string
map
type string
scala/Option
caller Method
descriptor string
()J
hidden boolean
false
modifiers int
2
name string
currentTaskAttemptId
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/storage/memory/MemoryStore
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/storage/memory
compileId int
72731
message string
inline
startTime long: millis
398044610743
succeeded boolean
true

Deoptimization

profiling default startTime eventThread stackTrace 14 17 21 25 26 27

Category: Java Virtual Machine / Compiler

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

Code Context

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

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

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

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

Configuration enabled stackTrace
profiling true true
default true false

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

Examples 3
action DeoptimizationAction
maybe_recompile
bci int
36
compileId int
76302
compiler CompilerType
c2
instruction Bytecode
if_icmplt
lineNumber int
654
method Method
descriptor string
(I)V
hidden boolean
false
modifiers int
2
name string
rollbackWriteBuffer
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
1025
name string
scala/concurrent/stm/ccstm/AccessHistory
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/concurrent/stm/ccstm
reason DeoptimizationReason
loop_limit_check
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
36
lineNumber int
654
method Method
descriptor string
(I)V
hidden boolean
false
modifiers int
2
name string
rollbackWriteBuffer
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
1025
name string
scala/concurrent/stm/ccstm/AccessHistory
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/concurrent/stm/ccstm
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
461942884121
action DeoptimizationAction
maybe_recompile
bci int
4
compileId int
79282
compiler CompilerType
c2
instruction Bytecode
invokeinterface
lineNumber int
206
method Method
descriptor string
()Lscala/reflect/runtime/SynchronizedSymbols;
hidden boolean
false
modifiers int
4097
name string
scala$reflect$runtime$SynchronizedSymbols$SynchronizedSymbol$$$outer
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
scala/reflect/runtime/SynchronizedSymbols$SynchronizedSymbol$$anon$8
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/reflect/runtime
reason DeoptimizationReason
bimorphic_or_optimized_type_check
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
4
lineNumber int
206
method Method
descriptor string
()Lscala/reflect/runtime/SynchronizedSymbols;
hidden boolean
false
modifiers int
4097
name string
scala$reflect$runtime$SynchronizedSymbols$SynchronizedSymbol$$$outer
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
scala/reflect/runtime/SynchronizedSymbols$SynchronizedSymbol$$anon$8
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/reflect/runtime
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
347579166732
action DeoptimizationAction
reinterpret
bci int
108
compileId int
76126
compiler CompilerType
c2
instruction Bytecode
ifne
lineNumber int
187
method Method
descriptor string
(Lscala/concurrent/stm/ccstm/TxnLevelImpl;Ljava/lang/Object;)V
hidden boolean
false
modifiers int
1
name string
awaitCompleted
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
scala/concurrent/stm/ccstm/TxnLevelImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/concurrent/stm/ccstm
reason DeoptimizationReason
unstable_if
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
108
lineNumber int
187
method Method
descriptor string
(Lscala/concurrent/stm/ccstm/TxnLevelImpl;Ljava/lang/Object;)V
hidden boolean
false
modifiers int
1
name string
awaitCompleted
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
scala/concurrent/stm/ccstm/TxnLevelImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/concurrent/stm/ccstm
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
426337924774

CompilerQueueUtilization

profiling default startTime duration every chunk 22 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/jfrCompilerQueueUtilization.cpp:

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

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

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

Configuration enabled period
profiling true 5 s
default true 10 s

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

CompilerStatistics

profiling default startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Compiler

Code Context

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

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

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

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

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

Configuration enabled period
profiling true 1000 ms
default true 1000 ms

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

Examples 3
bailoutCount int
15
compileCount int
84635
invalidatedCount int
0
nmethodCodeSize ulong: bytes
112012456
nmethodsSize ulong: bytes
165595472
osrBytesCompiled ulong: bytes
0
osrCompileCount int
971
peakTimeSpent long: millis
9396
standardBytesCompiled ulong: bytes
0
standardCompileCount int
83664
startTime long: millis
483904562231
totalTimeSpent long: millis
663224
bailoutCount int
16
compileCount int
88496
invalidatedCount int
0
nmethodCodeSize ulong: bytes
123178336
nmethodsSize ulong: bytes
178054792
osrBytesCompiled ulong: bytes
0
osrCompileCount int
1002
peakTimeSpent long: millis
6148
standardBytesCompiled ulong: bytes
0
standardCompileCount int
87494
startTime long: millis
367647061019
totalTimeSpent long: millis
345780
bailoutCount int
13
compileCount int
82684
invalidatedCount int
0
nmethodCodeSize ulong: bytes
109211480
nmethodsSize ulong: bytes
161492320
osrBytesCompiled ulong: bytes
0
osrCompileCount int
912
peakTimeSpent long: millis
7055
standardBytesCompiled ulong: bytes
0
standardCompileCount int
81772
startTime long: millis
441329578707
totalTimeSpent long: millis
814247

CompilerConfiguration

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

Category: Java Virtual Machine / Compiler

Code Context

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

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

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

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

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

Configuration enabled period
profiling true beginChunk
default true beginChunk

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

Examples 3
dynamicCompilerThreadCount boolean
true
startTime long: millis
403214734019
threadCount int
3
tieredCompilation boolean
true
dynamicCompilerThreadCount boolean
true
startTime long: millis
387265540918
threadCount int
3
tieredCompilation boolean
true
dynamicCompilerThreadCount boolean
true
startTime long: millis
487381469646
threadCount int
3
tieredCompilation boolean
true

JVM: Diagnostics

SyncOnValueBasedClass

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

Category: Java Virtual Machine / Diagnostics

Code Context

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

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

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

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

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

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

Configuration enabled stackTrace
profiling true true
default true true

Field Type Description
valueBasedClass Class Value Based Class

HeapDump

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

Category: Java Virtual Machine / Diagnostics

Information about a successfully written Java heap dump

Code Context

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

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

  thread_dumper.dump_stack_refs(segment_writer);
}

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

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

  AbstractCompressor* compressor = nullptr;

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

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

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

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

JavaAgent

profiling default startTime end of every chunk 21 25 26 27

Category: Java Virtual Machine / Diagnostics

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

Code Context

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

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

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

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

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

Configuration enabled period
profiling true endChunk
default true endChunk

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

NativeAgent

profiling default startTime end of every chunk 21 25 26 27

Category: Java Virtual Machine / Diagnostics

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

Code Context

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

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

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

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

TRACE_REQUEST_FUNC(NativeAgent) {
  const JvmtiAgentList::Iterator native_agents_it = JvmtiAgentList::native_agents();
  send_native_agent_events(native_agents_it);
  const JvmtiAgentList::Iterator xrun_agents_it = JvmtiAgentList::xrun_agents();
  send_native_agent_events(xrun_agents_it);
}

Configuration enabled period
profiling true endChunk
default true endChunk

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

JVM: Flag

IntFlagChanged

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Code Context

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

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

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

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

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

Configuration enabled
profiling true
default true

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

UnsignedIntFlagChanged

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Code Context

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

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

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

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

Configuration enabled
profiling true
default true

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

LongFlagChanged

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Code Context

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

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

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

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

Configuration enabled
profiling true
default true

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

UnsignedLongFlagChanged

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Code Context

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

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

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

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

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

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

Configuration enabled
profiling true
default true

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

DoubleFlagChanged

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Code Context

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

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

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

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

Configuration enabled
profiling true
default true

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

BooleanFlagChanged

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Code Context

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

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

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

    return JVMFlag::SUCCESS;
  }

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

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

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

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

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

Configuration enabled
profiling true
default true

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

StringFlagChanged

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / Flag

Code Context

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

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

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

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

Configuration enabled
profiling true
default true

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

IntFlag

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

Category: Java Virtual Machine / Flag

Configuration enabled period
profiling true beginChunk
default true beginChunk

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

Examples 3
name string
PerfMaxStringConstLength
origin FlagValueOrigin
Default
startTime long: millis
297002695018
value int
1024
name string
JavaPriority6_To_OSPriority
origin FlagValueOrigin
Default
startTime long: millis
408193202130
value int
-1
name string
VMThreadPriority
origin FlagValueOrigin
Default
startTime long: millis
351492530050
value int
-1

UnsignedIntFlag

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

Category: Java Virtual Machine / Flag

Configuration enabled period
profiling true beginChunk
default true beginChunk

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

Examples 3
name string
GCCardSizeInBytes
origin FlagValueOrigin
Default
startTime long: millis
319565657313
value uint
512
name string
G1ConcRefinementThreads
origin FlagValueOrigin
Default
startTime long: millis
416849048129
value uint
0
name string
StringDeduplicationAgeThreshold
origin FlagValueOrigin
Default
startTime long: millis
393178232945
value uint
3

LongFlag

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

Category: Java Virtual Machine / Flag

Configuration enabled period
profiling true beginChunk
default true beginChunk

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

Examples 3
name string
ConditionalMoveLimit
origin FlagValueOrigin
Default
startTime long: millis
398060570718
value long
3
name string
TraceDwarfLevel
origin FlagValueOrigin
Default
startTime long: millis
297002721017
value long
0
name string
Tier0BackedgeNotifyFreqLog
origin FlagValueOrigin
Default
startTime long: millis
351492558613
value long
10

UnsignedLongFlag

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

Category: Java Virtual Machine / Flag

Configuration enabled period
profiling true beginChunk
default true beginChunk

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

Examples 3
name string
MetadataAllocationFailALotInterval
origin FlagValueOrigin
Default
startTime long: millis
398060594262
value ulong
1000
name string
G1SATBBufferEnqueueingThresholdPercent
origin FlagValueOrigin
Default
startTime long: millis
351492586866
value ulong
60
name string
GCTimeRatio
origin FlagValueOrigin
Default
startTime long: millis
297002747056
value ulong
12

DoubleFlag

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

Category: Java Virtual Machine / Flag

Configuration enabled period
profiling true beginChunk
default true beginChunk

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

Examples 3
name string
EscapeAnalysisTimeout
origin FlagValueOrigin
Default
startTime long: millis
393178293098
value double
20.0
name string
MaxRAMPercentage
origin FlagValueOrigin
Default
startTime long: millis
398060611114
value double
25.0
name string
CompileThresholdScaling
origin FlagValueOrigin
Default
startTime long: millis
311710974044
value double
1.0

BooleanFlag

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

Category: Java Virtual Machine / Flag

Configuration enabled period
profiling true beginChunk
default true beginChunk

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

Examples 3
name string
NeverTenure
origin FlagValueOrigin
Default
startTime long: millis
398060659934
value boolean
false
name string
UseSHM
origin FlagValueOrigin
Default
startTime long: millis
351492732859
value boolean
false
name string
AlwaysPreTouch
origin FlagValueOrigin
Default
startTime long: millis
297002836182
value boolean
false

StringFlag

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

Category: Java Virtual Machine / Flag

Configuration enabled period
profiling true beginChunk
default true beginChunk

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

Examples 3
name string
InlineDataFile
origin FlagValueOrigin
Default
startTime long: millis
358305787559
value string
null
name string
ShenandoahGCMode
origin FlagValueOrigin
Default
startTime long: millis
297002848115
value string
satb
name string
CompileCommandFile
origin FlagValueOrigin
Default
startTime long: millis
399942777008
value string
null

JVM: GC: Collector

GarbageCollection

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

Category: Java Virtual Machine / GC / Collector

Garbage collection performed by the JVM

Code Context

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

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

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

typedef uintptr_t TraceAddress;

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

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

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

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

Examples 3
cause GCCause
G1 Humongous Allocation
gcId uint
922
longestPause Tickspan
0
name GCName
G1Old
startTime long: millis
304460600141
sumOfPauses Tickspan
0
cause GCCause
Heap Inspection Initiated GC
gcId uint
900
longestPause Tickspan
319467321
name GCName
SerialOld
startTime long: millis
398060761862
sumOfPauses Tickspan
319467321
cause GCCause
Heap Inspection Initiated GC
gcId uint
428
longestPause Tickspan
2183860
name GCName
ParallelScavenge
startTime long: millis
361259282948
sumOfPauses Tickspan
2183860

SystemGC

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

Category: Java Virtual Machine / GC / Collector

Code Context

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

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

    event.commit();
  }
JVM_END


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


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


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

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

Field Type Description
invokedConcurrent boolean Invoked Concurrent

Examples 3
invokedConcurrent boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
257
name string
gc
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Runtime
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
499641647743
invokedConcurrent boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
257
name string
gc
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Runtime
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
429911236137
invokedConcurrent boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
257
name string
gc
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Runtime
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
378786717555

ParallelOldGarbageCollection

profiling default startTime duration 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Collector

Appearing in: ParallelGC

Missing in: G1GC, SerialGC, ShenandoahGC, ZGC

Extra information specific to Parallel Old Garbage Collections

Code Context

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

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

    e.set_smallChunksTotalSize(summary.small_chunks_size_in_bytes());

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

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

    e.commit();
  }
}

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

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

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

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

Examples 1
densePrefix ulong: address
30424956928
gcId uint
511
startTime long: millis
454775511187

YoungGarbageCollection

profiling default startTime duration 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Collector

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, ZGC

Extra information specific to Young Garbage Collections

Code Context

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

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

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

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

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

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
tenuringThreshold uint Tenuring Threshold

Examples 3
gcId uint
486
startTime long: millis
436520576102
tenuringThreshold uint
13
gcId uint
929
startTime long: millis
457453430958
tenuringThreshold uint
15
gcId uint
981
startTime long: millis
341863097051
tenuringThreshold uint
15

OldGarbageCollection

profiling default startTime duration 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Collector

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, ZGC

Extra information specific to Old Garbage Collections

Code Context

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

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

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

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

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

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier

Examples 3
gcId uint
1021
startTime long: millis
500281592502
gcId uint
472
startTime long: millis
425224949592
gcId uint
1043
startTime long: millis
378038258954

G1GarbageCollection

profiling default startTime duration 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Collector

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Extra information specific to G1 Young Garbage Collections

Code Context

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

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

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

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

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

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

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
type G1YCType Type

Examples 1
gcId uint
941
startTime long: millis
314684195320
type G1YCType
Concurrent Start

ZYoungGarbageCollection

profiling default startTime duration eventThread 21 25 26 27

Category: Java Virtual Machine / GC / Collector

Extra information specific to ZGC Young Garbage Collections

Code Context

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

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

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

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

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

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

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

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

  EventZOldGarbageCollection e(UNTIMED);

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
tenuringThreshold uint Tenuring Threshold

ZOldGarbageCollection

profiling default startTime duration eventThread 21 25 26 27

Category: Java Virtual Machine / GC / Collector

Extra information specific to ZGC Old Garbage Collections

Code Context

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

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

  NoSafepointVerifier nsv;

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

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

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

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

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

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier

JVM: GC: Configuration

GCConfiguration

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

Category: Java Virtual Machine / GC / Configuration

The configuration of the garbage collector

Code Context

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

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

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

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

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

Configuration enabled period
profiling true everyChunk
default true everyChunk

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

Examples 3
concurrentGCThreads uint
1
gcTimeRatio uint
12
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
G1Old
parallelGCThreads uint
4
pauseTarget long: millis
-9223372036854775808
startTime long: millis
367142495941
usesDynamicGCThreads boolean
true
youngCollector GCName
G1New
concurrentGCThreads uint
0
gcTimeRatio uint
99
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
SerialOld
parallelGCThreads uint
0
pauseTarget long: millis
-9223372036854775808
startTime long: millis
491005757679
usesDynamicGCThreads boolean
true
youngCollector GCName
DefNew
concurrentGCThreads uint
0
gcTimeRatio uint
99
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
ParallelOld
parallelGCThreads uint
4
pauseTarget long: millis
-9223372036854775808
startTime long: millis
463035720867
usesDynamicGCThreads boolean
true
youngCollector GCName
ParallelScavenge

GCSurvivorConfiguration

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

Category: Java Virtual Machine / GC / Configuration

The configuration of the survivors of garbage collection

Code Context

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

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

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

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

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

Configuration enabled period
profiling true beginChunk
default true beginChunk

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

Examples 3
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
463035723311
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
334601004855
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
441907212849

GCTLABConfiguration

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

Category: Java Virtual Machine / GC / Configuration

The configuration of the Thread Local Allocation Buffers (TLABs)

Code Context

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

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

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

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

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

Configuration enabled period
profiling true beginChunk
default true beginChunk

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

Examples 3
minTLABSize ulong: bytes
2048
startTime long: millis
334601005987
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
minTLABSize ulong: bytes
2048
startTime long: millis
351651921549
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
minTLABSize ulong: bytes
2048
startTime long: millis
487855849927
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true

GCHeapConfiguration

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

Category: Java Virtual Machine / GC / Configuration

The configuration of the garbage collected heap

Code Context

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

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

  event.commit();
}

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

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

TRACE_REQUEST_FUNC(YoungGenerationConfiguration) {

Configuration enabled period
profiling true beginChunk
default true beginChunk

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

Examples 3
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
262144000
maxSize ulong: bytes
4194304000
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
309811547446
usesCompressedOops boolean
true
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
262144000
maxSize ulong: bytes
4194304000
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
443321485238
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
408547728840
usesCompressedOops boolean
true

YoungGenerationConfiguration

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

Category: Java Virtual Machine / GC / Configuration

The configuration of the young generation of the garbage collected heap

Code Context

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

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

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

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

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

Configuration enabled period
profiling true beginChunk
default true beginChunk

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

Examples 3
maxSize ulong: bytes
1397751808
minSize ulong: bytes
87031808
newRatio uint
2
startTime long: millis
458237049310
maxSize ulong: bytes
2516582400
minSize ulong: bytes
1363144
newRatio uint
2
startTime long: millis
319733105139
maxSize ulong: bytes
1397358592
minSize ulong: bytes
87359488
newRatio uint
2
startTime long: millis
510557156298

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/x/xTracer.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 XTracer::send_thread_debug(const char* name, const Ticks& start, const Ticks& end) {
  NoSafepointVerifier nsv;

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

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

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

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

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

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

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

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/x/xTracer.inline.hpp:

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

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

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

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

inline XTraceThreadDebug::~XTraceThreadDebug() {
  XTracer::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

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Code Context

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

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

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

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

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

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

Configuration enabled
profiling true
default true

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

Examples 1
gcId uint
939
gcTime long: millis
48
pauseTarget long: millis
200
startTime long: millis
312757542920
timeSlice long: millis
201

EvacuationInformation

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Code Context

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

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

  G1GCPauseTypeHelper::assert_is_young_pause(_pause);

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

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

Configuration enabled
profiling true
default true

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

Examples 1
allocationRegions uint
7
allocationRegionsUsedAfter ulong: bytes
11209376
allocationRegionsUsedBefore ulong: bytes
153472
bytesCopied ulong: bytes
11055904
cSetRegions uint
609
cSetUsedAfter ulong: bytes
0
cSetUsedBefore ulong: bytes
1276194456
gcId uint
975
regionsFreed uint
609
startTime long: millis
337737583038

ObjectCountAfterGC

startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, ZGC

Code Context

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

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

#if INCLUDE_SERVICES

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

bool ObjectCountEventSender::_should_send_requestable_event = false;

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

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

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

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

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

#endif // INCLUDE_SERVICES

Configuration enabled
profiling false
default false

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

Examples 3
count long
128328
gcId uint
904
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
startTime long: millis
403735804531
totalSize ulong: bytes
2053248
count long
138
gcId uint
431
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[F
package Package
null
startTime long: millis
367181098579
totalSize ulong: bytes
24002304
count long
62459
gcId uint
913
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/reflect/Method
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang/reflect
startTime long: millis
298966839832
totalSize ulong: bytes
5496392

G1EvacuationYoungStatistics

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Memory related evacuation statistics during GC for the young generation

Code Context

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

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

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

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

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

Configuration enabled
profiling true
default true

Field Type Description
statistics G1EvacuationStatistics struct Evacuation Statistics

Examples 1
startTime long: millis
311692841323
statistics G1EvacuationStatistics
allocated ulong: bytes
1447160
directAllocated ulong: bytes
157840
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
935
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
1
undoWaste ulong: bytes
0
used ulong: bytes
1360536
wasted ulong: bytes
2352

G1EvacuationOldStatistics

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Memory related evacuation statistics during GC for the old generation

Code Context

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

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

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

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

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

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

Configuration enabled
profiling true
default true

Field Type Description
statistics G1EvacuationStatistics struct Evacuation Statistics

Examples 1
startTime long: millis
361348333338
statistics G1EvacuationStatistics
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1023
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
0
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0

G1BasicIHOP

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Basic statistics related to current IHOP calculation

Code Context

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

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

  EventG1EvacuationOldStatistics old_evt;
  if (old_evt.should_commit()) {
    old_evt.set_statistics(create_g1_evacstats(GCId::current(), summary));
    old_evt.commit();
  }
}

void G1NewTracer::send_basic_ihop_statistics(size_t threshold,
                                             size_t target_occupancy,
                                             size_t current_occupancy,
                                             size_t last_allocation_size,
                                             double last_allocation_duration,
                                             double last_marking_length) {
  EventG1BasicIHOP evt;
  if (evt.should_commit()) {
    evt.set_gcId(GCId::current());
    evt.set_threshold(threshold);
    evt.set_targetOccupancy(target_occupancy);
    evt.set_thresholdPercentage(target_occupancy > 0 ? ((double)threshold / target_occupancy) : 0.0);
    evt.set_currentOccupancy(current_occupancy);
    evt.set_recentMutatorAllocationSize(last_allocation_size);
    evt.set_recentMutatorDuration(last_allocation_duration * MILLIUNITS);
    evt.set_recentAllocationRate(last_allocation_duration != 0.0 ? last_allocation_size / last_allocation_duration : 0.0);
    evt.set_lastMarkingDuration(last_marking_length * MILLIUNITS);
    evt.commit();

Configuration enabled
profiling true
default true

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

Examples 1
currentOccupancy ulong: bytes
289447560
gcId uint
1037
lastMarkingDuration long: millis
1403
recentAllocationRate double: bytes-per-second
0.0
recentMutatorAllocationSize ulong: bytes
0
recentMutatorDuration long: millis
2543
startTime long: millis
369701080935
targetOccupancy ulong: bytes
874512384
threshold ulong: bytes
64562102
thresholdPercentage float: percentage
0.0738264

G1AdaptiveIHOP

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Statistics related to current adaptive IHOP calculation

Code Context

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

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

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

void G1NewTracer::send_adaptive_ihop_statistics(size_t threshold,
                                                size_t internal_target_occupancy,
                                                size_t current_occupancy,
                                                size_t additional_buffer_size,
                                                double predicted_allocation_rate,
                                                double predicted_marking_length,
                                                bool prediction_active) {
  EventG1AdaptiveIHOP evt;
  if (evt.should_commit()) {
    evt.set_gcId(GCId::current());
    evt.set_threshold(threshold);
    evt.set_thresholdPercentage(internal_target_occupancy > 0 ? ((double)threshold / internal_target_occupancy) : 0.0);
    evt.set_ihopTargetOccupancy(internal_target_occupancy);
    evt.set_currentOccupancy(current_occupancy);
    evt.set_additionalBufferSize(additional_buffer_size);
    evt.set_predictedAllocationRate(predicted_allocation_rate);
    evt.set_predictedMarkingDuration(predicted_marking_length * MILLIUNITS);
    evt.set_predictionActive(prediction_active);
    evt.commit();

Configuration enabled
profiling true
default true

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

Examples 1
additionalBufferSize ulong: bytes
520093696
currentOccupancy ulong: bytes
264424688
gcId uint
1027
ihopTargetOccupancy ulong: bytes
824809881
predictedAllocationRate double: bytes-per-second
2.0795261666761062E8
predictedMarkingDuration long: millis
1653
predictionActive boolean
true
startTime long: millis
362274153300
threshold ulong: bytes
0
thresholdPercentage float: percentage
0.0

PromoteObjectInNewPLAB

profiling startTime eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC

Missing in: SerialGC, ShenandoahGC, ZGC

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

Code Context

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

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

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

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

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

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

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

Configuration enabled
profiling true
default false

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

Examples 2
gcId uint
921
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[F
package Package
null
objectSize ulong: bytes
56
plabSize ulong: bytes
8024
startTime long: millis
304455775571
tenured boolean
false
tenuringAge uint
0
gcId uint
424
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[F
package Package
null
objectSize ulong: bytes
56
plabSize ulong: bytes
32752
startTime long: millis
353959756812
tenured boolean
false
tenuringAge uint
0

PromoteObjectOutsidePLAB

profiling startTime eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC

Missing in: SerialGC, ShenandoahGC, ZGC

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

Code Context

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

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

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

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

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

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

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

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

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

void OldGCTracer::send_old_gc_event() const {

Configuration enabled
profiling true
default false

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

Examples 2
gcId uint
432
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
41936
startTime long: millis
370177000509
tenured boolean
false
tenuringAge uint
0
gcId uint
947
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1042
name string
[Ljava/io/ObjectInputStream$HandleTable$HandleList;
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/io
objectSize ulong: bytes
11280
startTime long: millis
319537220168
tenured boolean
false
tenuringAge uint
0

PromotionFailed

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Promotion of an object failed

Code Context

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

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

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

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

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

Configuration enabled
profiling true
default true

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

EvacuationFailed

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Evacuation of an object failed

Code Context

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

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

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

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

Configuration enabled
profiling true
default true

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

ConcurrentModeFailure

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Concurrent Mode failed

Code Context

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

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

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

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

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

Configuration enabled
profiling true
default true

Field Type Description
gcId uint GC Identifier

Examples 1
gcId uint
1052
startTime long: millis
389826132531

GCCPUTime

profiling default startTime 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, ZGC

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

Code Context

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

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

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

typedef uintptr_t TraceAddress;

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

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

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

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

Configuration enabled
profiling true
default true

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

Examples 3
gcId uint
942
realTime ulong: nanos
9999999
startTime long: millis
459110135714
systemTime ulong: nanos
0
userTime ulong: nanos
9999999
gcId uint
441
realTime ulong: nanos
160000000
startTime long: millis
388980056964
systemTime ulong: nanos
0
userTime ulong: nanos
500000000
gcId uint
957
realTime ulong: nanos
0
startTime long: millis
328918742615
systemTime ulong: nanos
0
userTime ulong: nanos
0

AllocationRequiringGC

startTime eventThread stackTrace 11 17 21 25 26 27 graal vm

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, ZGC

Code Context

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

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

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

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

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

Configuration enabled stackTrace
profiling false true
default false true

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

Examples 3
gcId uint
990
size ulong: bytes
40
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
371
method Method
descriptor string
()Ljava/util/Spliterator;
hidden boolean
false
modifiers int
1
name string
spliterator
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/HashSet
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/util
type FrameType
Inlined
truncated boolean
true
startTime long: millis
481588274671
gcId uint
981
size ulong: bytes
1048576
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
394
method Method
descriptor string
(Lscala/concurrent/stm/TxnExecutor;Lscala/Function1;)Ljava/lang/Object;
hidden boolean
false
modifiers int
2
name string
topLevelAtomicImpl
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
scala/concurrent/stm/ccstm/InTxnImpl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/concurrent/stm/ccstm
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
341862705231
gcId uint
463
size ulong: bytes
32
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
180
method Method
descriptor string
()Ljava/util/stream/ReduceOps$3ReducingSink;
hidden boolean
false
modifiers int
1
name string
makeSink
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/util/stream/ReduceOps$3
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/util/stream
type FrameType
Inlined
truncated boolean
true
startTime long: millis
421891268478

TenuringDistribution

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, SerialGC

Missing in: ParallelGC, ShenandoahGC, ZGC

Code Context

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

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

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

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

Configuration enabled
profiling true
default true

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

Examples 2
age uint
12
gcId uint
911
size ulong: bytes
0
startTime long: millis
297156966364
age uint
6
gcId uint
928
size ulong: bytes
1363856
startTime long: millis
457356015600

G1HeapRegionTypeChange

startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Information about a G1 heap region type change

Code Context

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

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

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

Configuration enabled
profiling false
default false

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

Examples 1
from G1HeapRegionType
Free
index uint
967
start ulong: address
32193380352
startTime long: millis
296978424614
to G1HeapRegionType
Free
used ulong: bytes
0

ObjectCount

startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, ZGC

Code Context

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

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

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

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

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

#endif // INCLUDE_SERVICES

Configuration enabled period
profiling false everyChunk
default false everyChunk

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

Examples 3
count long
96741
gcId uint
913
objectClass 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
21.0.10.0.1
name string
java/lang
startTime long: millis
298966839832
totalSize ulong: bytes
11273304
count long
33822
gcId uint
903
objectClass 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
21.0.10.0.1
name string
java/lang/invoke
startTime long: millis
401800115632
totalSize ulong: bytes
1352880
count long
398715
gcId uint
429
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
startTime long: millis
361366612720
totalSize ulong: bytes
65724232

G1HeapRegionInformation

startTime duration every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Information about a specific heap region in the G1 GC

Code Context

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

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

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

class VM_G1SendHeapRegionInfoEvents : public VM_Operation {
  virtual void doit() {
    DumpEventInfoClosure c;

Configuration enabled period
profiling false everyChunk
default false everyChunk

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

Examples 1
index uint
317
start ulong: address
30830231552
startTime long: millis
297164785007
type G1HeapRegionType
Continues Humongous
used ulong: bytes
2097152

ZAllocationStall

profiling default startTime duration eventThread 15 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

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/x/xPageAllocator.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 XPageAllocator::alloc_page_stall(XPageAllocation* allocation) {
  XStatTimer timer(XCriticalPhaseAllocationStall);
  EventZAllocationStall event;
  XPageAllocationStall 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
    XCollectedHeap::heap()->collect(GCCause::_z_allocation_stall);

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;

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

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

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

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
type ZPageTypeType Type
size ulong: bytes Size

Examples 1
size ulong: bytes
2097152
startTime long: millis
467314362172
type ZPageTypeType
Small

ZPageAllocation

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

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Allocation of a ZPage

Code Context

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

src/hotspot/share/gc/x/xPageAllocator.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();
}

XPage* XPageAllocator::alloc_page(uint8_t type, size_t size, XAllocationFlags flags) {
  EventZPageAllocation event;

retry:
  XPageAllocation 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

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

  // so that it will be re-inserted into the page cache.
  ZPage* const committed_page = page->split_committed();
  destroy_page(page);

  if (committed_page != nullptr) {
    map_page(committed_page);
    allocation->pages()->insert_last(committed_page);
  }

  return nullptr;
}

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

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

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

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

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

Examples 1
committed ulong: bytes
0
flushed ulong: bytes
0
nonBlocking boolean
false
segments uint
1
size ulong: bytes
2097152
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
12
lineNumber int
501
method Method
descriptor string
(Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
false
modifiers int
8
name string
allocateInstance
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/invoke/DirectMethodHandle
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang/invoke
type FrameType
Inlined
truncated boolean
false
startTime long: millis
468535793540
type ZPageTypeType
Small

ZRelocationSet

profiling default startTime duration eventThread 15 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Code Context

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

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

ZRelocationSetSelector::ZRelocationSetSelector(double fragmentation_limit)
  : _small("Small", ZPageType::small, ZPageSizeSmall, ZObjectSizeLimitSmall, fragmentation_limit),
    _medium("Medium", ZPageType::medium, ZPageSizeMedium, ZObjectSizeLimitMedium, fragmentation_limit),
    _large("Large", ZPageType::large, 0 /* page_size */, 0 /* object_size_limit */, fragmentation_limit),
    _empty_pages() {}

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

  EventZRelocationSet event;

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

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

ZRelocationSetSelectorStats ZRelocationSetSelector::stats() const {

src/hotspot/share/gc/x/xRelocationSetSelector.cpp:

XRelocationSetSelector::XRelocationSetSelector() :
    _small("Small", XPageTypeSmall, XPageSizeSmall, XObjectSizeLimitSmall),
    _medium("Medium", XPageTypeMedium, XPageSizeMedium, XObjectSizeLimitMedium),
    _large("Large", XPageTypeLarge, 0 /* page_size */, 0 /* object_size_limit */),
    _empty_pages() {}

void XRelocationSetSelector::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());
}

XRelocationSetSelectorStats XRelocationSetSelector::stats() const {

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

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

Examples 1
empty ulong: bytes
0
relocate ulong: bytes
5478528
startTime long: millis
489345684330
total ulong: bytes
413138944

ZRelocationSetGroup

profiling default startTime duration eventThread 15 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Code Context

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

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

    _stats[i]._relocate = selected_live_bytes[i];
    _stats[i]._npages_selected = npages_selected[i];
  }

  log_debug(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();
  } else {
    // Mark pages as not selected
    const int npages = _live_pages.length();
    for (int from = 1; from <= npages; from++) {
      ZPage* const page = _live_pages.at(from - 1);
      _not_selected_pages.append(page);
    }
  }

src/hotspot/share/gc/x/xRelocationSetSelector.cpp:

  // Update statistics
  _stats._relocate = selected_live_bytes;
  _stats._npages_selected = npages_selected;

  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 XRelocationSetSelectorGroup::select() {
  if (is_disabled()) {
    return;
  }

  EventZRelocationSetGroup event;

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

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

XRelocationSetSelector::XRelocationSetSelector() :
    _small("Small", XPageTypeSmall, XPageSizeSmall, XObjectSizeLimitSmall),

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
type ZPageTypeType Type
candidatePages ulong 21+ Candidate Pages
total ulong: bytes Total
empty ulong: bytes Empty
selectedPages ulong 21+ Selected Pages
relocate ulong: bytes 16+ Relocate

Examples 1
candidatePages ulong
8
empty ulong: bytes
6291456
relocate ulong: bytes
0
selectedPages ulong
0
startTime long: millis
378822575683
total ulong: bytes
71303168
type ZPageTypeType
Large

ZStatisticsCounter

experimental startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Code Context

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

src/hotspot/share/gc/x/xTracer.cpp:

XTracer::XTracer() :
    GCTracer(Z) {}

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

void XTracer::send_stat_counter(const XStatCounter& 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 XTracer::send_stat_sampler(const XStatSampler& sampler, uint64_t value) {
  NoSafepointVerifier nsv;

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

#ifndef SHARE_GC_Z_ZTRACER_INLINE_HPP
#define SHARE_GC_Z_ZTRACER_INLINE_HPP

#include "gc/z/zTracer.hpp"

#include "jfr/jfrEvents.hpp"

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

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

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

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

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

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

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

  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/x/xTracer.inline.hpp:

#ifndef SHARE_GC_X_XTRACER_INLINE_HPP
#define SHARE_GC_X_XTRACER_INLINE_HPP

#include "gc/x/xTracer.hpp"

#include "jfr/jfrEvents.hpp"

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

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

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

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

Configuration enabled threshold
profiling false 0 ms
default false 0 ms

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

Examples 1
id ZStatisticsCounterType
Page Cache Hit L1
increment ulong
1
startTime long: millis
378826796944
value ulong
6

ZStatisticsSampler

experimental startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Code Context

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

src/hotspot/share/gc/x/xTracer.cpp:

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

void XTracer::send_stat_sampler(const XStatSampler& sampler, uint64_t value) {
  NoSafepointVerifier nsv;

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

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

  EventZThreadPhase e(UNTIMED);

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

#define SHARE_GC_Z_ZTRACER_INLINE_HPP

#include "gc/z/zTracer.hpp"

#include "jfr/jfrEvents.hpp"

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

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

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

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

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/x/xTracer.inline.hpp:

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

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

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

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

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

Configuration enabled threshold
profiling false 0 ms
default false 0 ms

Field Type Description
id ZStatisticsSamplerType Id
value ulong Value

Examples 1
id ZStatisticsSamplerType
Concurrent Mark Free
startTime long: millis
378774561299
value ulong
942

ZThreadPhase

experimental startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Code Context

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

src/hotspot/share/gc/x/xTracer.cpp:

  NoSafepointVerifier nsv;

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

void XTracer::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 XTracer::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)

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/x/xTracer.inline.hpp:

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

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

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

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

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

Configuration enabled threshold
profiling false 0 ms
default false 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 1
gcId uint
220
name string
Concurrent Weak Roots OopStorageSet
startTime long: millis
405505988685

ZUncommit

profiling default startTime duration eventThread 15 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Uncommitting of memory

Code Context

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

src/hotspot/share/gc/x/xUncommitter.cpp:

bool XUncommitter::should_continue() const {
  XLocker<XConditionLock> locker(&_lock);
  return !_stop;
}

void XUncommitter::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;

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

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

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

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

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

      uncommitted += flushed;

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
uncommitted ulong: bytes Uncommitted

ZUnmap

profiling default startTime duration eventThread 17 21 until JDK 25

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Unmapping of memory

Code Context

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

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

size_t ZUnmapper::queue_capacity() const {
  return align_up<size_t>(_page_allocator->max_capacity() * ZAsyncUnmappingLimit / 100.0, ZGranuleSize);
}

bool ZUnmapper::is_saturated() const {
  return _enqueued_bytes >= queue_capacity();
}

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) {

src/hotspot/share/gc/x/xUnmapper.cpp:

size_t XUnmapper::queue_capacity() const {
  return align_up<size_t>(_page_allocator->max_capacity() * ZAsyncUnmappingLimit / 100.0, XGranuleSize);
}

bool XUnmapper::is_saturated() const {
  return _enqueued_bytes >= queue_capacity();
}

void XUnmapper::do_unmap_and_destroy_page(XPage* 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 XUnmapper::unmap_and_destroy_page(XPage* page) {

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
unmapped ulong: bytes Unmapped

Examples 1
startTime long: millis
455070452877
unmapped ulong: bytes
2097152

ShenandoahHeapRegionStateChange

startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Detailed

Appearing in: ShenandoahGC

Missing in: G1GC, ParallelGC, SerialGC, ZGC

Information about a Shenandoah heap region state change

Code Context

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

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

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

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

Configuration enabled
profiling false
default false

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

Examples 1
from ShenandoahHeapRegionState
Empty Uncommitted
index uint
150
start ulong: address
30324817920
startTime long: millis
369171398969
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: ShenandoahGC

Missing in: G1GC, ParallelGC, SerialGC, ZGC

Information about a specific heap region in the Shenandoah GC

Code Context

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

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

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

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

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

Configuration enabled period
profiling false everyChunk
default false everyChunk

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

Examples 1
index uint
3814
start ulong: address
34166800384
startTime long: millis
369481941105
state ShenandoahHeapRegionState
Empty Uncommitted
used ulong: bytes
0

GCLocker

profiling default startTime eventThread stackTrace 17 21 until JDK 25

Category: Java Virtual Machine / GC / Detailed

Code Context

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

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

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

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

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

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

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

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

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

JVM: GC: Heap

GCHeapSummary

profiling default startTime 11 17 21 25 26 27 graal vm

Category: Java Virtual Machine / GC / Heap

Code Context

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

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

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

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

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

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

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

Configuration enabled
profiling true
default true

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

Examples 3
gcId uint
934
heapSpace VirtualSpace
committedEnd ulong: address
31138512896
committedSize ulong: bytes
973078528
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4194304000
start ulong: address
30165434368
heapUsed ulong: bytes
398189256
startTime long: millis
310825054392
when GCWhen
Before GC
gcId uint
468
heapSpace VirtualSpace
committedEnd ulong: address
32787922944
committedSize ulong: bytes
2622488576
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4194304000
start ulong: address
30165434368
heapUsed ulong: bytes
245924120
startTime long: millis
423809933811
when GCWhen
After GC
gcId uint
922
heapSpace VirtualSpace
committedEnd ulong: address
31154188288
committedSize ulong: bytes
986656768
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4192206848
start ulong: address
30167531520
heapUsed ulong: bytes
236735768
startTime long: millis
456966071939
when GCWhen
After GC

MetaspaceSummary

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Heap

Code Context

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

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

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

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

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

Configuration enabled
profiling true
default true

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

Examples 3
classSpace MetaspaceSizes
committed ulong: bytes
88276992
reserved ulong: bytes
1073741824
used ulong: bytes
86404632
dataSpace MetaspaceSizes
committed ulong: bytes
571277312
reserved ulong: bytes
603979776
used ulong: bytes
569423536
gcId uint
912
gcThreshold ulong: bytes
1099300864
metaspace MetaspaceSizes
committed ulong: bytes
659554304
reserved ulong: bytes
1677721600
used ulong: bytes
655828168
startTime long: millis
431818056331
when GCWhen
Before GC
classSpace MetaspaceSizes
committed ulong: bytes
89980928
reserved ulong: bytes
1073741824
used ulong: bytes
88094144
dataSpace MetaspaceSizes
committed ulong: bytes
583663616
reserved ulong: bytes
603979776
used ulong: bytes
581693008
gcId uint
461
gcThreshold ulong: bytes
1122566144
metaspace MetaspaceSizes
committed ulong: bytes
673644544
reserved ulong: bytes
1677721600
used ulong: bytes
669787152
startTime long: millis
421423221186
when GCWhen
Before GC
classSpace MetaspaceSizes
committed ulong: bytes
88276992
reserved ulong: bytes
1073741824
used ulong: bytes
86378200
dataSpace MetaspaceSizes
committed ulong: bytes
571146240
reserved ulong: bytes
603979776
used ulong: bytes
569233368
gcId uint
920
gcThreshold ulong: bytes
1098645504
metaspace MetaspaceSizes
committed ulong: bytes
659423232
reserved ulong: bytes
1677721600
used ulong: bytes
655611568
startTime long: millis
303663868691
when GCWhen
Before GC

PSHeapSummary

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Heap

Appearing in: ParallelGC

Missing in: G1GC, SerialGC, ShenandoahGC, ZGC

Code Context

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

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

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

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

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

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

Configuration enabled
profiling true
default true

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

Examples 1
edenSpace ObjectSpace
end ulong: address
33925103616
size ulong: bytes
963117056
start ulong: address
32961986560
used ulong: bytes
963117056
fromSpace ObjectSpace
end ulong: address
34010038272
size ulong: bytes
38797312
start ulong: address
33971240960
used ulong: bytes
37437632
gcId uint
467
oldObjectSpace ObjectSpace
end ulong: address
31730958336
size ulong: bytes
1565523968
start ulong: address
30165434368
used ulong: bytes
202719288
oldSpace VirtualSpace
committedEnd ulong: address
31730958336
committedSize ulong: bytes
1565523968
reservedEnd ulong: address
32961986560
reservedSize ulong: bytes
2796552192
start ulong: address
30165434368
startTime long: millis
423377926115
toSpace ObjectSpace
end ulong: address
33971240960
size ulong: bytes
46137344
start ulong: address
33925103616
used ulong: bytes
0
when GCWhen
Before GC
youngSpace VirtualSpace
committedEnd ulong: address
34032058368
committedSize ulong: bytes
1070071808
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
1397751808
start ulong: address
32961986560

G1HeapSummary

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Heap

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Code Context

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

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

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

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

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

Configuration enabled
profiling true
default true

Field Type Description
gcId uint GC Identifier
when GCWhen When
edenUsedSize ulong: bytes Eden Used Size
edenTotalSize ulong: bytes Eden Total Size
survivorUsedSize ulong: bytes Survivor Used Size
oldGenUsedSize ulong: bytes 21+ Old Generation Used Size
numberOfRegions uint Number of Regions

Examples 1
edenTotalSize ulong: bytes
541065216
edenUsedSize ulong: bytes
4194304
gcId uint
932
numberOfRegions uint
464
oldGenUsedSize ulong: bytes
285958592
startTime long: millis
309824817526
survivorUsedSize ulong: bytes
0
when GCWhen
Before GC

JVM: GC: Metaspace

MetaspaceGCThreshold

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Metaspace

Code Context

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

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

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

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

Configuration enabled
profiling true
default true

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

Examples 3
newValue ulong: bytes
1469579264
oldValue ulong: bytes
1408827392
startTime long: millis
442644515460
updater GCThresholdUpdater
compute_new_size
newValue ulong: bytes
1450967040
oldValue ulong: bytes
1450246144
startTime long: millis
360730432052
updater GCThresholdUpdater
compute_new_size
newValue ulong: bytes
1518600192
oldValue ulong: bytes
1477967872
startTime long: millis
487303816388
updater GCThresholdUpdater
compute_new_size

MetaspaceAllocationFailure

profiling default startTime stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Metaspace

Code Context

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

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

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

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

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

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

Configuration enabled stackTrace
profiling true true
default true true

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

MetaspaceOOM

profiling default startTime stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Metaspace

Code Context

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

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

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

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

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

Configuration enabled stackTrace
profiling true true
default true true

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

MetaspaceChunkFreeListSummary

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Metaspace

Code Context

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

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

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

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

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

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

Configuration enabled
profiling true
default true

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

Examples 3
gcId uint
930
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
309621376773
when GCWhen
Before GC
gcId uint
903
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
401577178570
when GCWhen
Before GC
gcId uint
443
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
389263761529
when GCWhen
Before GC

JVM: GC: Phases

GCPhasePause

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

Category: Java Virtual Machine / GC / Phases

Code Context

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

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

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

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

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

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 3, "There are only three levels for ConcurrentPhase");

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
439
name string
GC Pause
startTime long: millis
387934878279
gcId uint
908
name string
GC Pause
startTime long: millis
416849298265
gcId uint
927
name string
Pause Remark
startTime long: millis
306314829729

GCPhasePauseLevel1

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

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Missing in: ZGC

Code Context

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

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

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

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

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

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 3, "There are only three levels for ConcurrentPhase");

    switch (phase->level()) {

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
916
name string
Phase 2: Compute new object addresses
startTime long: millis
453495958358
gcId uint
909
name string
Notify Soft/WeakReferences
startTime long: millis
296976369451
gcId uint
424
name string
Weak Processing
startTime long: millis
353960088515

GCPhasePauseLevel2

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

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, ZGC

Code Context

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

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

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

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

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

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 3, "There are only three levels for ConcurrentPhase");

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

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
907
name string
Weak Processing
startTime long: millis
411517914732
gcId uint
927
name string
Unregister NMethods
startTime long: millis
306323255379
gcId uint
423
name string
Par Mark
startTime long: millis
351495542149

GCPhasePauseLevel3

startTime duration eventThread 11 17 21 25 26 27 graal vm

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, ZGC

Code Context

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

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

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

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

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

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 3, "There are only three levels for ConcurrentPhase");

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

Configuration enabled threshold
profiling false 0 ms
default false 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
905
name string
Trigger cleanups
startTime long: millis
405477721851
gcId uint
914
name string
Free Code Blobs
startTime long: millis
299532384798
gcId uint
431
name string
ClassLoaderData
startTime long: millis
367129705787

GCPhasePauseLevel4

startTime duration eventThread 11 17 21 25 26 27 graal vm

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ParallelGC

Missing in: SerialGC, ShenandoahGC, ZGC

Code Context

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

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

    e.commit();
  }
}

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

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

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 3, "There are only three levels for ConcurrentPhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhaseConcurrent>(phase); break;
      case 1: send_phase<EventGCPhaseConcurrentLevel1>(phase); break;
      case 2: send_phase<EventGCPhaseConcurrentLevel2>(phase); break;

Configuration enabled threshold
profiling false 0 ms
default false 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 2
gcId uint
965
name string
Balance queues
startTime long: millis
334510913762
gcId uint
470
name string
Balance queues
startTime long: millis
424772624690

GCPhaseConcurrent

profiling default startTime duration eventThread 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ShenandoahGC, ZGC

Missing in: ParallelGC, SerialGC

Code Context

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

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

class ShenandoahWorkerSession : public StackObj {
protected:
  ShenandoahWorkerSession(uint worker_id);
public:
  static inline uint worker_id() {
    return WorkerThread::worker_id();
  }
};

class ShenandoahConcurrentWorkerSession : public ShenandoahWorkerSession {
private:
  EventGCPhaseConcurrent _event;

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

class ShenandoahParallelWorkerSession : public ShenandoahWorkerSession {
private:
  EventGCPhaseParallel _event;

public:

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

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

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 3, "There are only three levels for ConcurrentPhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhaseConcurrent>(phase); break;
      case 1: send_phase<EventGCPhaseConcurrentLevel1>(phase); break;
      case 2: send_phase<EventGCPhaseConcurrentLevel2>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

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

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
226
name string
Concurrent Mark Free
startTime long: millis
453992649155
gcId uint
995
name string
Concurrent Preclean
startTime long: millis
348809438833
gcId uint
252
name string
Concurrent cleanup
startTime long: millis
371686240172

GCPhaseConcurrentLevel1

profiling default startTime duration eventThread 15 17 21 25 26 27

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ShenandoahGC, ZGC

Missing in: ParallelGC, SerialGC

Code Context

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

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

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

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 3, "There are only three levels for ConcurrentPhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhaseConcurrent>(phase); break;
      case 1: send_phase<EventGCPhaseConcurrentLevel1>(phase); break;
      case 2: send_phase<EventGCPhaseConcurrentLevel2>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

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

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
267
name string
ClassLoaderData
startTime long: millis
387972143390
gcId uint
242
name string
Trigger cleanups
startTime long: millis
469310965578
gcId uint
982
name string
Preclean WeakReferences
startTime long: millis
342131233360

GCPhaseConcurrentLevel2

profiling default startTime duration eventThread 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:

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

  void visit_concurrent(GCPhase* phase) {
    assert(phase->level() < 3, "There are only three levels for ConcurrentPhase");

    switch (phase->level()) {
      case 0: send_phase<EventGCPhaseConcurrent>(phase); break;
      case 1: send_phase<EventGCPhaseConcurrentLevel1>(phase); break;
      case 2: send_phase<EventGCPhaseConcurrentLevel2>(phase); break;
      default: /* Ignore sending this phase */ break;
    }
  }

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

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

GCPhaseParallel

profiling default startTime duration eventThread 12 17 21 25 26 27

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ShenandoahGC

Missing in: ParallelGC, SerialGC, ZGC

GC phases for parallel workers

Code Context

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

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

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

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

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

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

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

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

class G1EvacuateRegionsBaseTask : public WorkerTask {

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

  size_t cards_scanned() const { return _cards_scanned; }
  size_t blocks_scanned() const { return _blocks_scanned; }
  size_t chunks_claimed() const { return _chunks_claimed; }
  size_t heap_roots_found() const { return _heap_roots_found; }
};

void G1RemSet::scan_heap_roots(G1ParScanThreadState* pss,
                               uint worker_id,
                               G1GCPhaseTimes::GCParPhases scan_phase,
                               G1GCPhaseTimes::GCParPhases objcopy_phase,
                               bool remember_already_scanned_cards) {
  EventGCPhaseParallel event;
  G1ScanHRForRegionClosure cl(_scan_state, pss, worker_id, scan_phase, remember_already_scanned_cards);
  _scan_state->iterate_dirty_regions_from(&cl, worker_id);

  event.commit(GCId::current(), worker_id, G1GCPhaseTimes::phase_name(scan_phase));

  G1GCPhaseTimes* p = _g1p->phase_times();

  p->record_or_add_time_secs(objcopy_phase, worker_id, cl.rem_set_trim_partially_time().seconds());

  p->record_or_add_time_secs(scan_phase, worker_id, cl.rem_set_root_scan_time().seconds());

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

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

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

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

    // Scan code root remembered sets.
    {
      EventGCPhaseParallel event;
      G1EvacPhaseWithTrimTimeTracker timer(_pss, _code_root_scan_time, _code_trim_partially_time);
      G1ScanAndCountCodeBlobClosure cl(_pss->closures()->weak_codeblobs());

      // Scan the code root list attached to the current region
      r->code_roots_do(&cl);

      _code_roots_scanned += cl.count();

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

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

    _before_used_bytes += used;
    _regions_freed += 1;
  }

  void account_card_rs_length(HeapRegion* r) {
    _card_rs_length += r->rem_set()->occupied();
  }
};

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

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

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

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

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

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

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

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

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

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

#ifndef SHARE_GC_G1_G1GCPARPHASETIMESTRACKER_HPP
#define SHARE_GC_G1_G1GCPARPHASETIMESTRACKER_HPP

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

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

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

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

Configuration enabled threshold
profiling true 0 ms
default true 0 ms

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

Examples 2
gcId uint
909
gcWorkerId uint
0
name string
RetireTLABsAndFlushLogs
startTime long: millis
296972938460
gcId uint
262
gcWorkerId uint
0
name string
Finish Mark
startTime long: millis
382367425587

JVM: GC: Reference

GCReferenceStatistics

profiling default startTime 11 17 21 25 26 27

Category: Java Virtual Machine / GC / Reference

Total count of processed references during GC

Code Context

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

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

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

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

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

Configuration enabled
profiling true
default true

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

Examples 3
count ulong
236
gcId uint
906
startTime long: millis
408320269768
type ReferenceType
Final reference
count ulong
0
gcId uint
917
startTime long: millis
302523280132
type ReferenceType
Soft reference
count ulong
4
gcId uint
434
startTime long: millis
377608583589
type ReferenceType
Phantom reference

JVM: Heap

GCHeapMemoryUsage

profiling default startTime every chunk 21 25 26 27

Category: Java Virtual Machine / 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:

TRACE_REQUEST_FUNC(JavaThreadStatistics) {
  EventJavaThreadStatistics event;
  event.set_activeCount(ThreadService::get_live_thread_count());
  event.set_daemonCount(ThreadService::get_daemon_thread_count());
  event.set_accumulatedCount(ThreadService::get_total_thread_count());
  event.set_peakCount(ThreadService::get_peak_thread_count());
  event.commit();
}

TRACE_REQUEST_FUNC(GCHeapMemoryUsage) {
  MemoryUsage usage = Universe::heap()->memory_usage();
  EventGCHeapMemoryUsage event(UNTIMED);
  event.set_used(usage.used());
  event.set_committed(usage.committed());
  event.set_max(usage.max_size());
  event.set_starttime(timestamp());
  event.set_endtime(timestamp());
  event.commit();
}

TRACE_REQUEST_FUNC(GCHeapMemoryPoolUsage) {
  ResourceMark mark;
  GrowableArray<MemoryPool*> pools = Universe::heap()->memory_pools();

Configuration enabled period
profiling true everyChunk
default true everyChunk

Field Type Description
used ulong: bytes Heap Used Bytes allocated for storing objects on the heap
committed ulong: bytes Heap Committed Bytes committed for storing objects on the heap
max ulong: bytes Heap Max Max size for the heap

Examples 3
committed ulong: bytes
986656768
max ulong: bytes
4052484096
startTime long: millis
487365000561
used ulong: bytes
263811520
committed ulong: bytes
2803367936
max ulong: bytes
3728736256
startTime long: millis
451229793913
used ulong: bytes
282860288
committed ulong: bytes
874512384
max ulong: bytes
4194304000
startTime long: millis
373241904952
used ulong: bytes
392232784

GCHeapMemoryPoolUsage

profiling default startTime every chunk 21 25 26 27

Category: Java Virtual Machine / 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_max(usage.max_size());
  event.set_starttime(timestamp());
  event.set_endtime(timestamp());
  event.commit();
}

TRACE_REQUEST_FUNC(GCHeapMemoryPoolUsage) {
  ResourceMark mark;
  GrowableArray<MemoryPool*> pools = Universe::heap()->memory_pools();
  for (int i = 0; i < pools.length(); i++) {
    MemoryPool* pool = pools.at(i);
    if (pool->is_heap()) {
      MemoryUsage usage = pool->get_memory_usage();
      EventGCHeapMemoryPoolUsage event(UNTIMED);
      event.set_name(pool->name());
      event.set_used(usage.used());
      event.set_committed(usage.committed());
      event.set_max(usage.max_size());
      event.set_starttime(timestamp());
      event.set_endtime(timestamp());
      event.commit();
    }
  }
}

Configuration enabled period
profiling true everyChunk
default true everyChunk

Field Type Description
name string Name GC Heap Memory Pool Name
used ulong: bytes GC Heap Memory Pool Used Bytes used for storing objects in this memory pool
committed ulong: bytes GC Heap Memory Pool Committed Bytes committed for storing objects in this memory pool
max ulong: bytes GC Heap Memory Pool Max Max size for storing objects in this memory pool

Examples 3
committed ulong: bytes
2097152
max ulong: bytes
-1
name string
G1 Survivor Space
startTime long: millis
306755821614
used ulong: bytes
660576
committed ulong: bytes
680407040
max ulong: bytes
2794848256
name string
Tenured Gen
startTime long: millis
475971792587
used ulong: bytes
237383864
committed ulong: bytes
1080033280
max ulong: bytes
1080033280
name string
PS Eden Space
startTime long: millis
443098909427
used ulong: bytes
192330784

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/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/EventProvider.java:

        void setIsOsr(boolean isOsr);

        void setCodeSize(int codeSize);

        void setInlinedBytes(int inlinedBytes);
    }

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

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

        void setMessage(String message);
    }
}

Value

internal startTime eventThread 18 21 25 26 27

Category: Java Virtual Machine / Internal

Field Type Description
value ulong Value

Text

internal startTime eventThread 18 21 25 26 27

Category: Java Virtual Machine / Internal

Field Type Description
text string Text

JVM: Memory

ResidentSetSize

profiling default startTime duration every chunk 21 25 26 27

Category: Java Virtual Machine / Memory

Resident set size of the process

Code Context

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

src/hotspot/os/windows/os_windows.cpp:

#if INCLUDE_JFR

void os::jfr_report_memory_info() {
  PROCESS_MEMORY_COUNTERS_EX pmex;
  ZeroMemory(&pmex, sizeof(PROCESS_MEMORY_COUNTERS_EX));
  pmex.cb = sizeof(pmex);

  BOOL ret = GetProcessMemoryInfo(GetCurrentProcess(), (PROCESS_MEMORY_COUNTERS*) &pmex, sizeof(pmex));
  if (ret != 0) {
    // Send the RSS JFR event
    EventResidentSetSize event;
    event.set_size(pmex.WorkingSetSize);
    event.set_peak(pmex.PeakWorkingSetSize);
    event.commit();
  } else {
    // Log a warning
    static bool first_warning = true;
    if (first_warning) {
      log_warning(jfr)("Error fetching RSS values: GetProcessMemoryInfo failed");
      first_warning = false;
    }
  }

src/hotspot/os/linux/os_linux.cpp:

  if (!print_model_name_and_flags(st, buf, buflen)) {
    _print_ascii_file_h("/proc/cpuinfo", "/proc/cpuinfo", st, false);
  }
  st->cr();
  print_sys_devices_cpu_info(st);
}

#if INCLUDE_JFR

void os::jfr_report_memory_info() {
  os::Linux::meminfo_t info;
  if (os::Linux::query_process_memory_info(&info)) {
    // Send the RSS JFR event
    EventResidentSetSize event;
    event.set_size(info.vmrss * K);
    event.set_peak(info.vmhwm * K);
    event.commit();
  } else {
    // Log a warning
    static bool first_warning = true;
    if (first_warning) {
      log_warning(jfr)("Error fetching RSS values: query_process_memory_info failed");
      first_warning = false;
    }
  }

src/hotspot/os/bsd/os_bsd.cpp:

void os::print_memory_mappings(char* addr, size_t bytes, outputStream* st) {}

#if INCLUDE_JFR

void os::jfr_report_memory_info() {
#ifdef __APPLE__
  mach_task_basic_info info;
  mach_msg_type_number_t count = MACH_TASK_BASIC_INFO_COUNT;

  kern_return_t ret = task_info(mach_task_self(), MACH_TASK_BASIC_INFO, (task_info_t)&info, &count);
  if (ret == KERN_SUCCESS) {
    // Send the RSS JFR event
    EventResidentSetSize event;
    event.set_size(info.resident_size);
    // We've seen that resident_size_max sometimes trails resident_size with one page.
    // Make sure we always report size <= peak
    event.set_peak(MAX2(info.resident_size_max, info.resident_size));
    event.commit();
  } else {
    // Log a warning
    static bool first_warning = true;
    if (first_warning) {
      log_warning(jfr)("Error fetching RSS values: task_info failed");
      first_warning = false;

Configuration enabled period
profiling true 1000 ms
default true 1000 ms

Field Type Description
size ulong: bytes Resident Set Size Resident set size of the process
peak ulong: bytes Resident Set Size Peak Value Resident set size peak value of the process

Examples 3
peak ulong: bytes
5425512448
size ulong: bytes
2856136704
startTime long: millis
357365681684
peak ulong: bytes
4228743168
size ulong: bytes
2799112192
startTime long: millis
452284582161
peak ulong: bytes
5530562560
size ulong: bytes
4679729152
startTime long: millis
414429261605

NativeMemoryUsage

profiling default startTime duration every chunk 20 21 25 26 27

Category: Java Virtual Machine / Memory

Native memory usage for a given memory type in the JVM

Code Context

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

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

    return;
  }

  NMTUsage* usage = get_usage(timestamp);

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

void JfrNativeMemoryEvent::send_type_event(const Ticks& starttime, MEMFLAGS flag, size_t reserved, size_t committed) {
  EventNativeMemoryUsage event(UNTIMED);
  event.set_starttime(starttime);
  event.set_type(NMTUtil::flag_to_index(flag));
  event.set_reserved(reserved);
  event.set_committed(committed);
  event.commit();
}

void JfrNativeMemoryEvent::send_type_events(const Ticks& timestamp) {
  if (!MemTracker::enabled()) {
    return;
  }

Configuration enabled period
profiling true 1000 ms
default true 1000 ms

Field Type Description
type NMTType Memory Type Type used for the native memory allocation
reserved ulong: bytes Reserved Memory Reserved bytes for this type
committed ulong: bytes Committed Memory Committed bytes for this type

NativeMemoryUsageTotal

profiling default startTime duration every chunk 20 21 25 26 27

Category: Java Virtual Machine / Memory

Total native memory usage for the JVM. Might not be the exact sum of the NativeMemoryUsage events due to timeing.

Code Context

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

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

    usage->refresh();
    last_timestamp = timestamp;
  }
  return usage;
}

void JfrNativeMemoryEvent::send_total_event(const Ticks& timestamp) {
  if (!MemTracker::enabled()) {
    return;
  }

  NMTUsage* usage = get_usage(timestamp);

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

void JfrNativeMemoryEvent::send_type_event(const Ticks& starttime, MEMFLAGS flag, size_t reserved, size_t committed) {
  EventNativeMemoryUsage event(UNTIMED);
  event.set_starttime(starttime);
  event.set_type(NMTUtil::flag_to_index(flag));
  event.set_reserved(reserved);

Configuration enabled period
profiling true 1000 ms
default true 1000 ms

Field Type Description
reserved ulong: bytes Reserved Memory Total amount of reserved bytes for the JVM
committed ulong: bytes Committed Memory Total amount of committed bytes for the JVM

JVM: Profiling

OldObjectSample

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

Category: Java Virtual Machine / Profiling

Appearing in: G1GC, ParallelGC, SerialGC, ZGC

Missing in: ShenandoahGC

A potential memory leak

Code Context

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

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

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

NO_TRANSITION(void, jfr_retransform_classes(JNIEnv* env, jclass jvm, jobjectArray classes))
  JfrJvmtiAgent::retransform_classes(env, classes, JavaThread::thread_from_jni_environment(env));
NO_TRANSITION_END

NO_TRANSITION(void, jfr_set_enabled(JNIEnv* env, jclass jvm, jlong event_type_id, jboolean enabled))
  JfrEventSetting::set_enabled(event_type_id, JNI_TRUE == enabled);
  if (EventOldObjectSample::eventId == event_type_id) {
    JavaThread* thread = JavaThread::thread_from_jni_environment(env);
    MACOS_AARCH64_ONLY(ThreadWXEnable __wx(WXWrite, thread));
    ThreadInVMfromNative transition(thread);
    if (JNI_TRUE == enabled) {
      LeakProfiler::start(JfrOptionSet::old_object_queue_size());
    } else {
      LeakProfiler::stop();
    }
  }
NO_TRANSITION_END

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

    // for regular threads, the blob is cached in the thread local data structure
    tl->set_thread_blob(JfrCheckpointManager::create_thread_blob(thread, tid));
    assert(tl->has_thread_blob(), "invariant");
  }
  return tl->thread_blob();
}

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

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

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

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

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

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

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

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

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

Examples 3
allocationTime Ticks
462124890239
arrayElements int
64
lastKnownHeapUsage ulong: bytes
263636960
object OldObject
address ulong: address
30412826536
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[Ljava/util/concurrent/ForkJoinTask;
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/util/concurrent
objectAge Tickspan
9289808619
objectSize ulong: bytes
272
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
32
lineNumber int
1607
method Method
descriptor string
(Ljava/util/concurrent/ForkJoinPool$WorkQueue;)V
hidden boolean
false
modifiers int
16
name string
registerWorker
type 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
21.0.10.0.1
name string
java/util/concurrent
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
471414698858
allocationTime Ticks
509318823370
arrayElements int
16
lastKnownHeapUsage ulong: bytes
281980968
object OldObject
address ulong: address
31813036704
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
2000279862
objectSize ulong: bytes
32
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
1
lineNumber int
211
method Method
descriptor string
([CII)[B
hidden boolean
false
modifiers int
9
name string
compress
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
16
name string
java/lang/StringUTF16
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
511319103232
allocationTime Ticks
389045465405
arrayElements int
-2147483648
lastKnownHeapUsage ulong: bytes
273477248
object OldObject
address ulong: address
31018090648
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
io/netty/util/concurrent/DefaultPromise
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/util/concurrent
objectAge Tickspan
570422417
objectSize ulong: bytes
32
root OldObjectGcRoot
null
stackTrace StackTrace
null
startTime long: millis
389615887822

ExecutionSample

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

Category: Java Virtual Machine / Profiling

Snapshot of a threads state

Code Context

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

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

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

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

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

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

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

  // Skip sample if we signaled a thread that moved to other state
  if (!thread_state_in_java(jt)) {
    return;
  }
  JfrGetCallTrace trace(true, jt);
  frame topframe;
  if (trace.get_topframe(context.ucontext(), topframe)) {
    if (_stacktrace.record_async(jt, topframe)) {
      /* If we managed to get a topframe and a stacktrace, create an event
      * and put it into our array. We can't call Jfr::_stacktraces.add()
      * here since it would allocate memory using malloc. Doing so while
      * the stopped thread is inside malloc would deadlock. */
      _success = true;
      EventExecutionSample *ev = _closure.next_event();
      ev->set_starttime(_suspend_time);
      ev->set_endtime(_suspend_time); // fake to not take an end time
      ev->set_sampledThread(JfrThreadLocal::thread_id(jt));
      ev->set_state(static_cast<u8>(JavaThreadStatus::RUNNABLE));
    }
  }
}

void OSThreadSampler::take_sample() {
  run();
}

src/hotspot/share/jfr/periodic/sampling/jfrThreadSampler.cpp:

  // skip frames in stack chunks on the Java heap.
  StackWatermarkSet::start_processing(thread, StackWatermarkKind::gc);

  OSThreadSampler sampler(thread, *this, frames, max_frames);
  sampler.take_sample();
  /* We don't want to allocate any memory using malloc/etc while the thread
  * is stopped, so everything is stored in stack allocated memory until this
  * point where the thread has been resumed again, if the sampling was a success
  * we need to store the stacktrace in the stacktrace repository and update
  * the event with the id that was returned. */
  if (!sampler.success()) {
    return false;
  }
  EventExecutionSample *event = &_events[_added_java - 1];
  traceid id = JfrStackTraceRepository::add(sampler.stacktrace());
  assert(id != 0, "Stacktrace id should not be 0");
  event->set_stackTrace(id);
  return true;
}

bool JfrThreadSampleClosure::sample_thread_in_native(JavaThread* thread, JfrStackFrame* frames, u4 max_frames) {
  // Process the oops in the thread head before calling into code that wants to
  // stack walk over Loom continuations. The stack walking code will otherwise
  // skip frames in stack chunks on the Java heap.
  StackWatermarkSet::start_processing(thread, StackWatermarkKind::gc);

src/hotspot/share/jfr/periodic/sampling/jfrThreadSampler.cpp:

  EventNativeMethodSample *event = &_events_native[_added_native - 1];
  traceid id = JfrStackTraceRepository::add(cb.stacktrace());
  assert(id != 0, "Stacktrace id should not be 0");
  event->set_stackTrace(id);
  return true;
}

static const uint MAX_NR_OF_JAVA_SAMPLES = 5;
static const uint MAX_NR_OF_NATIVE_SAMPLES = 1;

void JfrThreadSampleClosure::commit_events(JfrSampleType type) {
  if (JAVA_SAMPLE == type) {
    assert(_added_java > 0 && _added_java <= MAX_NR_OF_JAVA_SAMPLES, "invariant");
    if (EventExecutionSample::is_enabled()) {
      for (uint i = 0; i < _added_java; ++i) {
        _events[i].commit();
      }
    }
  } else {
    assert(NATIVE_SAMPLE == type, "invariant");
    assert(_added_native > 0 && _added_native <= MAX_NR_OF_NATIVE_SAMPLES, "invariant");
    if (EventNativeMethodSample::is_enabled()) {
      for (uint i = 0; i < _added_native; ++i) {
        _events_native[i].commit();
      }
    }
  }
}

JfrThreadSampleClosure::JfrThreadSampleClosure(EventExecutionSample* events, EventNativeMethodSample* events_native) :
  _events(events),
  _events_native(events_native),
  _self(Thread::current()),
  _added_java(0),
  _added_native(0) {
}

class JfrThreadSampler : public NonJavaThread {
  friend class JfrThreadSampling;
 private:
  Semaphore _sample;

src/hotspot/share/jfr/periodic/sampling/jfrThreadSampler.cpp:

const JfrBuffer* JfrThreadSampler::get_enqueue_buffer() {
  const JfrBuffer* buffer = JfrTraceIdLoadBarrier::get_sampler_enqueue_buffer(this);
  return buffer != nullptr ? renew_if_full(buffer) : JfrTraceIdLoadBarrier::renew_sampler_enqueue_buffer(this);
}

const JfrBuffer* JfrThreadSampler::renew_if_full(const JfrBuffer* enqueue_buffer) {
  assert(enqueue_buffer != nullptr, "invariant");
  return enqueue_buffer->free_size() < _min_size ? JfrTraceIdLoadBarrier::renew_sampler_enqueue_buffer(this) : enqueue_buffer;
}

void JfrThreadSampler::task_stacktrace(JfrSampleType type, JavaThread** last_thread) {
  ResourceMark rm;
  EventExecutionSample samples[MAX_NR_OF_JAVA_SAMPLES];
  EventNativeMethodSample samples_native[MAX_NR_OF_NATIVE_SAMPLES];
  JfrThreadSampleClosure sample_task(samples, samples_native);

  const uint sample_limit = JAVA_SAMPLE == type ? MAX_NR_OF_JAVA_SAMPLES : MAX_NR_OF_NATIVE_SAMPLES;
  uint num_samples = 0;
  JavaThread* start = nullptr;
  {
    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, jclass jvm, jobject log_tag, jint id))
  JfrJavaLog::subscribe_log_level(log_tag, id, thread);
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_set_output(JNIEnv* env, jclass jvm, jstring path))
  JfrRepository::set_chunk_path(path, thread);
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_set_method_sampling_period(JNIEnv* env, jclass jvm, jlong type, jlong periodMillis))
  if (periodMillis < 0) {
    periodMillis = 0;
  }
  JfrEventId typed_event_id = (JfrEventId)type;
  assert(EventExecutionSample::eventId == typed_event_id || EventNativeMethodSample::eventId == typed_event_id, "invariant");
  JfrEventSetting::set_enabled(typed_event_id, periodMillis > 0);
  if (EventExecutionSample::eventId == type) {
    JfrThreadSampling::set_java_sample_period(periodMillis);
  } else {
    JfrThreadSampling::set_native_sample_period(periodMillis);
  }
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_store_metadata_descriptor(JNIEnv* env, jclass jvm, jbyteArray descriptor))
  JfrMetadataEvent::update(descriptor);
JVM_END

// trace thread id for a thread object

Configuration enabled period
profiling true 10 ms
default true 20 ms

Field Type Description
sampledThread Thread Thread
stackTrace StackTrace Stack Trace
state ThreadState Thread State

Examples 3
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 9.0 in stage 16.0 (TID 96)
javaThreadId long
1202
osName string
Executor task launch worker for task 9.0 in stage 16.0 (TID 96)
osThreadId long
3842
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
297
lineNumber int
171
method Method
descriptor string
(Lscala/collection/Iterator;)V
hidden boolean
false
modifiers int
1
name string
write
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
16
name string
org/apache/spark/shuffle/sort/BypassMergeSortShuffleWriter
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/shuffle/sort
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
398555242166
state ThreadState
STATE_RUNNABLE
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 4.0 in stage 18.0 (TID 111)
javaThreadId long
1153
osName string
Executor task launch worker for task 4.0 in stage 18.0 (TID 111)
osThreadId long
3765
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
132
lineNumber int
58
method Method
descriptor string
([BII[BII)I
hidden boolean
false
modifiers int
8
name string
compress64k
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
16
name string
net/jpountz/lz4/LZ4JavaUnsafeCompressor
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
net/jpountz/lz4
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
299230311720
state ThreadState
STATE_RUNNABLE
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 7.0 in stage 18.0 (TID 114)
javaThreadId long
1224
osName string
Executor task launch worker for task 7.0 in stage 18.0 (TID 114)
osThreadId long
3867
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
70
lineNumber int
443
method Method
descriptor string
(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
false
modifiers int
1
name string
put
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/IdentityHashMap
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/util
type FrameType
Inlined
truncated boolean
true
startTime long: millis
349496672556
state ThreadState
STATE_RUNNABLE

NativeMethodSample

profiling default startTime every chunk 11 17 21 25 26 27 graal vm

Category: Java Virtual Machine / Profiling

Snapshot of a threads state when in native

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/sampling/jfrThreadSampler.cpp:

    case _thread_in_native_trans:
      break;
    case _thread_in_native:
      return true;
    default:
      ShouldNotReachHere();
      break;
  }
  return false;
}

class JfrThreadSampleClosure {
 public:
  JfrThreadSampleClosure(EventExecutionSample* events, EventNativeMethodSample* events_native);
  ~JfrThreadSampleClosure() {}
  EventExecutionSample* next_event() { return &_events[_added_java++]; }
  EventNativeMethodSample* next_event_native() { return &_events_native[_added_native++]; }
  void commit_events(JfrSampleType type);
  bool do_sample_thread(JavaThread* thread, JfrStackFrame* frames, u4 max_frames, JfrSampleType type);
  uint java_entries() { return _added_java; }
  uint native_entries() { return _added_native; }

 private:
  bool sample_thread_in_java(JavaThread* thread, JfrStackFrame* frames, u4 max_frames);
  bool sample_thread_in_native(JavaThread* thread, JfrStackFrame* frames, u4 max_frames);
  EventExecutionSample* _events;
  EventNativeMethodSample* _events_native;
  Thread* _self;
  uint _added_java;
  uint _added_native;
};

class OSThreadSampler : public SuspendedThreadTask {
 public:
  OSThreadSampler(JavaThread* thread,
                  JfrThreadSampleClosure& closure,
                  JfrStackFrame *frames,
                  u4 max_frames) : SuspendedThreadTask((Thread*)thread),

src/hotspot/share/jfr/periodic/sampling/jfrThreadSampler.cpp:

  virtual void call();
  bool success() { return _success; }
  JfrStackTrace& stacktrace() { return _stacktrace; }

 private:
  JfrThreadSampleClosure& _closure;
  JavaThread* _jt;
  oop _thread_oop;
  JfrStackTrace _stacktrace;
  bool _success;
};

static void write_native_event(JfrThreadSampleClosure& closure, JavaThread* jt, oop thread_oop) {
  EventNativeMethodSample *ev = closure.next_event_native();
  ev->set_starttime(JfrTicks::now());
  ev->set_sampledThread(JfrThreadLocal::thread_id(jt));
  ev->set_state(static_cast<u8>(JavaThreadStatus::RUNNABLE));
}

void JfrNativeSamplerCallback::call() {
  // When a thread is only attach it will be native without a last java frame
  if (!_jt->has_last_Java_frame()) {
    return;
  }

src/hotspot/share/jfr/periodic/sampling/jfrThreadSampler.cpp:

  JfrNativeSamplerCallback cb(*this, thread, frames, max_frames);
  if (JfrOptionSet::sample_protection()) {
    ThreadCrashProtection crash_protection;
    if (!crash_protection.call(cb)) {
      log_error(jfr)("Thread method sampler crashed for native");
    }
  } else {
    cb.call();
  }
  if (!cb.success()) {
    return false;
  }
  EventNativeMethodSample *event = &_events_native[_added_native - 1];
  traceid id = JfrStackTraceRepository::add(cb.stacktrace());
  assert(id != 0, "Stacktrace id should not be 0");
  event->set_stackTrace(id);
  return true;
}

static const uint MAX_NR_OF_JAVA_SAMPLES = 5;
static const uint MAX_NR_OF_NATIVE_SAMPLES = 1;

void JfrThreadSampleClosure::commit_events(JfrSampleType type) {
  if (JAVA_SAMPLE == type) {
    assert(_added_java > 0 && _added_java <= MAX_NR_OF_JAVA_SAMPLES, "invariant");
    if (EventExecutionSample::is_enabled()) {
      for (uint i = 0; i < _added_java; ++i) {
        _events[i].commit();
      }
    }
  } else {
    assert(NATIVE_SAMPLE == type, "invariant");
    assert(_added_native > 0 && _added_native <= MAX_NR_OF_NATIVE_SAMPLES, "invariant");
    if (EventNativeMethodSample::is_enabled()) {
      for (uint i = 0; i < _added_native; ++i) {
        _events_native[i].commit();
      }
    }
  }
}

JfrThreadSampleClosure::JfrThreadSampleClosure(EventExecutionSample* events, EventNativeMethodSample* events_native) :
  _events(events),
  _events_native(events_native),
  _self(Thread::current()),
  _added_java(0),
  _added_native(0) {
}

class JfrThreadSampler : public NonJavaThread {
  friend class JfrThreadSampling;
 private:
  Semaphore _sample;

src/hotspot/share/jfr/periodic/sampling/jfrThreadSampler.cpp:

const JfrBuffer* JfrThreadSampler::get_enqueue_buffer() {
  const JfrBuffer* buffer = JfrTraceIdLoadBarrier::get_sampler_enqueue_buffer(this);
  return buffer != nullptr ? renew_if_full(buffer) : JfrTraceIdLoadBarrier::renew_sampler_enqueue_buffer(this);
}

const JfrBuffer* JfrThreadSampler::renew_if_full(const JfrBuffer* enqueue_buffer) {
  assert(enqueue_buffer != nullptr, "invariant");
  return enqueue_buffer->free_size() < _min_size ? JfrTraceIdLoadBarrier::renew_sampler_enqueue_buffer(this) : enqueue_buffer;
}

void JfrThreadSampler::task_stacktrace(JfrSampleType type, JavaThread** last_thread) {
  ResourceMark rm;
  EventExecutionSample samples[MAX_NR_OF_JAVA_SAMPLES];
  EventNativeMethodSample samples_native[MAX_NR_OF_NATIVE_SAMPLES];
  JfrThreadSampleClosure sample_task(samples, samples_native);

  const uint sample_limit = JAVA_SAMPLE == type ? MAX_NR_OF_JAVA_SAMPLES : MAX_NR_OF_NATIVE_SAMPLES;
  uint num_samples = 0;
  JavaThread* start = nullptr;
  {
    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, jclass jvm, jobject log_tag, jint id))
  JfrJavaLog::subscribe_log_level(log_tag, id, thread);
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_set_output(JNIEnv* env, jclass jvm, jstring path))
  JfrRepository::set_chunk_path(path, thread);
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_set_method_sampling_period(JNIEnv* env, jclass jvm, jlong type, jlong periodMillis))
  if (periodMillis < 0) {
    periodMillis = 0;
  }
  JfrEventId typed_event_id = (JfrEventId)type;
  assert(EventExecutionSample::eventId == typed_event_id || EventNativeMethodSample::eventId == typed_event_id, "invariant");
  JfrEventSetting::set_enabled(typed_event_id, periodMillis > 0);
  if (EventExecutionSample::eventId == type) {
    JfrThreadSampling::set_java_sample_period(periodMillis);
  } else {
    JfrThreadSampling::set_native_sample_period(periodMillis);
  }
JVM_END

JVM_ENTRY_NO_ENV(void, jfr_store_metadata_descriptor(JNIEnv* env, jclass jvm, jbyteArray descriptor))
  JfrMetadataEvent::update(descriptor);
JVM_END

Configuration enabled period
profiling true 20 ms
default true 20 ms

Field Type Description
sampledThread Thread Thread
stackTrace StackTrace Stack Trace
state ThreadState Thread State

Examples 3
sampledThread Thread
group ThreadGroup
name string
finagle/netty4
parent ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
finagle/netty4-2-8
javaThreadId long
858
osName string
finagle/netty4-2-8
osThreadId long
3407
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(IJII)I
hidden boolean
false
modifiers int
266
name string
epollWait
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
io/netty/channel/epoll/Native
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/channel/epoll
type FrameType
Native
truncated boolean
false
startTime long: millis
299143643164
state ThreadState
STATE_RUNNABLE
sampledThread Thread
group ThreadGroup
name string
finagle/netty4/boss
parent ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
finagle/netty4/boss-1
javaThreadId long
887
osName string
finagle/netty4/boss-1
osThreadId long
3460
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(IJII)I
hidden boolean
false
modifiers int
266
name string
epollWait
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
io/netty/channel/epoll/Native
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/channel/epoll
type FrameType
Native
truncated boolean
false
startTime long: millis
350035024499
state ThreadState
STATE_RUNNABLE
sampledThread Thread
group ThreadGroup
name string
finagle/netty4
parent ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
finagle/netty4-2-6
javaThreadId long
887
osName string
finagle/netty4-2-6
osThreadId long
3486
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(IJII)I
hidden boolean
false
modifiers int
266
name string
epollWait
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
17
name string
io/netty/channel/epoll/Native
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/channel/epoll
type FrameType
Native
truncated boolean
false
startTime long: millis
398866879063
state ThreadState
STATE_RUNNABLE

JVM: Runtime

ContinuationFreeze

experimental startTime duration eventThread stackTrace 19 21 25 26 27

Category: Java Virtual Machine / Runtime

Invocation of Continuation.yield()

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/continuationFreezeThaw.cpp:

  JVMTI_ONLY(jvmti_yield_cleanup(thread, cont)); // can safepoint
  return freeze_epilog(thread, cont);
}

template<typename ConfigT>
static inline int freeze_internal(JavaThread* current, intptr_t* const sp) {
  assert(!current->has_pending_exception(), "");

#ifdef ASSERT
  log_trace(continuations)("~~~~ freeze sp: " INTPTR_FORMAT, p2i(current->last_continuation()->entry_sp()));
  log_frames(current);
#endif

  CONT_JFR_ONLY(EventContinuationFreeze event;)

  ContinuationEntry* entry = current->last_continuation();

  oop oopCont = entry->cont_oop(current);
  assert(oopCont == current->last_continuation()->cont_oop(current), "");
  assert(ContinuationEntry::assert_entry_frame_laid_out(current), "");

  verify_continuation(oopCont);
  ContinuationWrapper cont(current, oopCont);
  log_develop_debug(continuations)("FREEZE #" INTPTR_FORMAT " " INTPTR_FORMAT, cont.hash(), p2i((oopDesc*)oopCont));

Configuration enabled stackTrace threshold
profiling false false 0 ms
default false false 0 ms

Field Type Description
carrierThread Thread Carrier Thread Thread enlisted as a carrier
continuationClass Class Continuation Class
interpretedFrames ushort Interpreted Frames
size ushort: bytes Stack Size

ContinuationThaw

experimental startTime duration eventThread stackTrace 19 21 25 26 27

Category: Java Virtual Machine / Runtime

Invocation of Continuation.run() on a started continuation

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/continuationFreezeThaw.cpp:

    " to: " INTPTR_FORMAT " top_address: " INTPTR_FORMAT, p2i(f.sp() - frame::metadata_words), p2i(_top_stack_address));
  ContinuationHelper::Frame::patch_pc(f, f.raw_pc()); // in case we want to deopt the frame in a full transition, this is checked.
  ContinuationHelper::push_pd(f);

  assert(ContinuationHelper::Frame::assert_frame_laid_out(f), "");
}

// returns new top sp
// called after preparations (stack overflow check and making room)
template<typename ConfigT>
static inline intptr_t* thaw_internal(JavaThread* thread, const Continuation::thaw_kind kind) {
  assert(thread == JavaThread::current(), "Must be current thread");

  CONT_JFR_ONLY(EventContinuationThaw event;)

  log_develop_trace(continuations)("~~~~ thaw kind: %d sp: " INTPTR_FORMAT, kind, p2i(thread->last_continuation()->entry_sp()));

  ContinuationEntry* entry = thread->last_continuation();
  assert(entry != nullptr, "");
  oop oopCont = entry->cont_oop(thread);

  assert(!jdk_internal_vm_Continuation::done(oopCont), "");
  assert(oopCont == get_continuation(thread), "");
  verify_continuation(oopCont);

Configuration enabled stackTrace threshold
profiling false false 0 ms
default false false 0 ms

Field Type Description
carrierThread Thread Carrier Thread Thread enlisted as a carrier
continuationClass Class Continuation Class
interpretedFrames ushort Interpreted Frames
size ushort: bytes Stack Size

ContinuationFreezeFast

experimental startTime eventThread 20 21 25 26 27

Category: Java Virtual Machine / Runtime

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/continuationFreezeThaw.cpp:

  log_develop_trace(continuations)("FREEZE CHUNK #" INTPTR_FORMAT " (young)", _cont.hash());
  LogTarget(Trace, continuations) lt;
  if (lt.develop_is_enabled()) {
    LogStream ls(lt);
    chunk->print_on(true, &ls);
  }

  // Verification
  assert(_cont.chunk_invariant(), "");
  chunk->verify();

#if CONT_JFR
  EventContinuationFreezeFast e;
  if (e.should_commit()) {
    e.set_id(cast_from_oop<u8>(chunk));
    DEBUG_ONLY(e.set_allocate(chunk_is_allocated);)
    e.set_size(cont_size() << LogBytesPerWord);
    e.commit();
  }
#endif
}

NOINLINE freeze_result FreezeBase::freeze_slow() {
#ifdef ASSERT

Configuration enabled
profiling false
default false

Field Type Description
id ulong Continuation ID
size uint Size
allocate boolean Allocated New

ContinuationFreezeSlow

experimental startTime eventThread 20 21 25 26 27

Category: Java Virtual Machine / Runtime

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/continuationFreezeThaw.cpp:

NOINLINE freeze_result FreezeBase::freeze_slow() {
#ifdef ASSERT
  ResourceMark rm;
#endif

  log_develop_trace(continuations)("freeze_slow  #" INTPTR_FORMAT, _cont.hash());
  assert(_thread->thread_state() == _thread_in_vm || _thread->thread_state() == _thread_blocked, "");

#if CONT_JFR
  EventContinuationFreezeSlow e;
  if (e.should_commit()) {
    e.set_id(cast_from_oop<u8>(_cont.continuation()));
    e.commit();
  }
#endif

  init_rest();

  HandleMark hm(Thread::current());

  frame f = freeze_start_frame();

Configuration enabled
profiling false
default false

Field Type Description
id ulong Continuation ID

ContinuationThawFast

experimental startTime eventThread 20 21 25 26 27

Category: Java Virtual Machine / Runtime

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/continuationFreezeThaw.cpp:

  log_develop_trace(continuations)("setting entry argsize: %d", _cont.argsize());
  assert(rs.bottom_sp() == _cont.entry()->bottom_sender_sp(), "");

  // install the return barrier if not last frame, or the entry's pc if last
  patch_return(rs.bottom_sp(), is_last);

  // insert the back links from callee to caller frames
  patch_caller_links(rs.top(), rs.top() + rs.total_size());

  assert(is_last == _cont.is_empty(), "");
  assert(_cont.chunk_invariant(), "");

#if CONT_JFR
  EventContinuationThawFast e;
  if (e.should_commit()) {
    e.set_id(cast_from_oop<u8>(chunk));
    e.set_size(thaw_size << LogBytesPerWord);
    e.set_full(!partial);
    e.commit();
  }
#endif

#ifdef ASSERT
  set_anchor(_thread, rs.sp());
  log_frames(_thread);

Configuration enabled
profiling false
default false

Field Type Description
id ulong Continuation ID
full boolean Full
size uint Size

ContinuationThawSlow

experimental startTime eventThread 20 21 25 26 27

Category: Java Virtual Machine / Runtime

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/continuationFreezeThaw.cpp:

inline bool ThawBase::seen_by_gc() {
  return _barriers || _cont.tail()->is_gc_mode();
}

NOINLINE intptr_t* ThawBase::thaw_slow(stackChunkOop chunk, bool return_barrier) {
  LogTarget(Trace, continuations) lt;
  if (lt.develop_is_enabled()) {
    LogStream ls(lt);
    ls.print_cr("thaw slow return_barrier: %d " INTPTR_FORMAT, return_barrier, p2i(chunk));
    chunk->print_on(true, &ls);
  }

#if CONT_JFR
  EventContinuationThawSlow e;
  if (e.should_commit()) {
    e.set_id(cast_from_oop<u8>(_cont.continuation()));
    e.commit();
  }
#endif

  DEBUG_ONLY(_frames = 0;)
  _align_size = 0;
  int num_frames = (return_barrier ? 1 : 2);

  _stream = StackChunkFrameStream<ChunkFrames::Mixed>(chunk);

Configuration enabled
profiling false
default false

Field Type Description
id ulong Continuation ID

ReservedStackActivation

profiling default startTime eventThread stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime

Activation of Reserved Stack Area caused by stack overflow with ReservedStackAccess annotated method in call stack

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/sharedRuntime.cpp:

        for (ScopeDesc *sd = nm->scope_desc_near(fr.pc()); sd != nullptr; sd = sd->sender()) {
          method = sd->method();
          if (method != nullptr && method->has_reserved_stack_access()) {
            found = true;
      }
    }
      }
    }
    if (found) {
      activation = fr;
      warning("Potentially dangerous stack overflow in "
              "ReservedStackAccess annotated method %s [%d]",
              method->name_and_sig_as_C_string(), count++);
      EventReservedStackActivation event;
      if (event.should_commit()) {
        event.set_method(method);
        event.commit();
      }
    }
  }
  return activation;
}

void SharedRuntime::on_slowpath_allocation_exit(JavaThread* current) {
  // After any safepoint, just before going back to compiled code,

Configuration enabled stackTrace
profiling true true
default true true

Field Type Description
method Method Java Method

SafepointBegin

profiling default startTime duration eventThread 11 17 21 25 26 27 graal vm

Category: Java Virtual Machine / Runtime / Safepoint

Safepointing begin

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/safepoint.cpp:

static void post_safepoint_begin_event(EventSafepointBegin& event,
                                       uint64_t safepoint_id,
                                       int thread_count,
                                       int critical_thread_count) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.set_totalThreadCount(thread_count);
    event.set_jniCriticalThreadCount(critical_thread_count);
    event.commit();
  }
}

src/hotspot/share/runtime/safepoint.cpp:

    SafepointMechanism::arm_local_poll(cur);
  }
  if (UseSystemMemoryBarrier) {
    SystemMemoryBarrier::emit(); // storestore|storeload, global state -> local state
  } else {
    OrderAccess::fence(); // storestore|storeload, global state -> local state
  }
}

// Roll all threads forward to a safepoint and suspend them all
void SafepointSynchronize::begin() {
  assert(Thread::current()->is_VM_thread(), "Only VM thread may execute a safepoint");

  EventSafepointBegin begin_event;
  SafepointTracing::begin(VMThread::vm_op_type());

  Universe::heap()->safepoint_synchronize_begin();

  // By getting the Threads_lock, we assure that no threads are about to start or
  // exit. It is released again in SafepointSynchronize::end().
  Threads_lock->lock();

  assert( _state == _not_synchronized, "trying to safepoint synchronize with wrong state");

  int nof_threads = Threads::number_of_threads();

Configuration enabled threshold
profiling true 0 ms
default true 10 ms

Field Type Description
safepointId ulong Safepoint Identifier
totalThreadCount int Total Threads The total number of threads at the start of safe point
jniCriticalThreadCount int JNI Critical Threads The number of threads in JNI critical sections

Examples 3
jniCriticalThreadCount int
0
safepointId ulong
1212
startTime long: millis
405331260205
totalThreadCount int
180
jniCriticalThreadCount int
0
safepointId ulong
1510
startTime long: millis
302817534388
totalThreadCount int
180
jniCriticalThreadCount int
0
safepointId ulong
728
startTime long: millis
397865506785
totalThreadCount int
192

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,
                                             int iterations) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.set_initialThreadCount(initial_number_of_threads);
    event.set_runningThreadCount(threads_waiting_to_block);
    event.set_iterations(checked_cast<u4>(iterations));
    event.commit();
  }

src/hotspot/share/runtime/safepoint.cpp:

  _current_jni_active_count = 0;

  // Set number of threads to wait for
  _waiting_to_block = nof_threads;

  jlong safepoint_limit_time = 0;
  if (SafepointTimeout) {
    // Set the limit time, so that it can be compared to see if this has taken
    // too long to complete.
    safepoint_limit_time = SafepointTracing::start_of_safepoint() + (jlong)(SafepointTimeoutDelay * NANOSECS_PER_MILLISEC);
    timeout_error_printed = false;
  }

  EventSafepointStateSynchronization sync_event;
  int initial_running = 0;

  // Arms the safepoint, _current_jni_active_count and _waiting_to_block must be set before.
  arm_safepoint();

  // Will spin until all threads are safe.
  int iterations = synchronize_threads(safepoint_limit_time, nof_threads, &initial_running);
  assert(_waiting_to_block == 0, "No thread should be running");

#ifndef PRODUCT
  // Mark all threads

Configuration enabled threshold
profiling false 0 ms
default false 10 ms

Field Type Description
safepointId ulong Safepoint Identifier
initialThreadCount int Initial Threads The number of threads running at the beginning of state check
runningThreadCount int Running Threads The number of threads still running
iterations int Iterations Number of state check iterations

Examples 3
initialThreadCount int
3
iterations int
3
runningThreadCount int
0
safepointId ulong
1206
startTime long: millis
401577024072
initialThreadCount int
2
iterations int
3
runningThreadCount int
0
safepointId ulong
1539
startTime long: millis
310980430603
initialThreadCount int
0
iterations int
1
runningThreadCount int
0
safepointId ulong
757
startTime long: millis
423791459053

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,
                                             int iterations) {

src/hotspot/share/runtime/safepoint.cpp:

  // Update the count of active JNI critical regions
  GCLocker::set_jni_lock_count(_current_jni_active_count);

  post_safepoint_synchronize_event(sync_event,
                                   _safepoint_id,
                                   initial_running,
                                   _waiting_to_block, iterations);

  SafepointTracing::synchronized(nof_threads, initial_running, _nof_threads_hit_polling_page);

  // We do the safepoint cleanup first since a GC related safepoint
  // needs cleanup to be completed before running the GC op.
  EventSafepointCleanup cleanup_event;
  do_cleanup_tasks();
  post_safepoint_cleanup_event(cleanup_event, _safepoint_id);

  post_safepoint_begin_event(begin_event, _safepoint_id, nof_threads, _current_jni_active_count);
  SafepointTracing::cleanup();
}

void SafepointSynchronize::disarm_safepoint() {
  uint64_t active_safepoint_counter = _safepoint_counter;
  {
    JavaThreadIteratorWithHandle jtiwh;

Configuration enabled threshold
profiling false 0 ms
default false 10 ms

Field Type Description
safepointId ulong Safepoint Identifier

Examples 3
safepointId ulong
1224
startTime long: millis
416849221332
safepointId ulong
686
startTime long: millis
353945124017
safepointId ulong
1574
startTime long: millis
326790257546

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,
                                             int iterations) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.set_initialThreadCount(initial_number_of_threads);
    event.set_runningThreadCount(threads_waiting_to_block);
    event.set_iterations(checked_cast<u4>(iterations));
    event.commit();
  }
}

static void post_safepoint_cleanup_task_event(EventSafepointCleanupTask& event,
                                              uint64_t safepoint_id,
                                              const char* name) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.set_name(name);
    event.commit();
  }
}

static void post_safepoint_end_event(EventSafepointEnd& event, uint64_t safepoint_id) {
  if (event.should_commit()) {

src/hotspot/share/runtime/safepoint.cpp:

  if (StringTable::needs_rehashing()) return true;
  if (SymbolTable::needs_rehashing()) return true;
  return false;
}

class ParallelCleanupTask : public WorkerTask {
private:
  SubTasksDone _subtasks;
  bool _do_lazy_roots;

  class Tracer {
  private:
    const char*               _name;
    EventSafepointCleanupTask _event;
    TraceTime                 _timer;

  public:
    Tracer(const char* name) :
        _name(name),
        _event(),
        _timer(name, TRACETIME_LOG(Info, safepoint, cleanup)) {}
    ~Tracer() {
      post_safepoint_cleanup_task_event(_event, SafepointSynchronize::safepoint_id(), _name);
    }
  };

Configuration enabled threshold
profiling false 0 ms
default false 10 ms

Field Type Description
safepointId ulong Safepoint Identifier
name string Task Name The task name

Examples 3
name string
updating inline caches
safepointId ulong
759
startTime long: millis
425223299257
name string
updating inline caches
safepointId ulong
1522
startTime long: millis
306033634933
name string
updating inline caches
safepointId ulong
1249
startTime long: millis
453611559376

SafepointEnd

startTime duration eventThread 11 17 21 25 26 27 graal vm

Category: Java Virtual Machine / Runtime / Safepoint

Safepointing end

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/safepoint.cpp:

static void post_safepoint_cleanup_task_event(EventSafepointCleanupTask& event,
                                              uint64_t safepoint_id,
                                              const char* name) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.set_name(name);
    event.commit();
  }
}

static void post_safepoint_end_event(EventSafepointEnd& event, uint64_t safepoint_id) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.commit();
  }
}

// SafepointCheck
SafepointStateTracker::SafepointStateTracker(uint64_t safepoint_id, bool at_safepoint)
  : _safepoint_id(safepoint_id), _at_safepoint(at_safepoint) {}

bool SafepointStateTracker::safepoint_state_changed() {

src/hotspot/share/runtime/safepoint.cpp:

  } // ~JavaThreadIteratorWithHandle

  // Release threads lock, so threads can be created/destroyed again.
  Threads_lock->unlock();

  // Wake threads after local state is correctly set.
  _wait_barrier->disarm();
}

// Wake up all threads, so they are ready to resume execution after the safepoint
// operation has been carried out
void SafepointSynchronize::end() {
  assert(Threads_lock->owned_by_self(), "must hold Threads_lock");
  EventSafepointEnd event;
  assert(Thread::current()->is_VM_thread(), "Only VM thread can execute a safepoint");

  disarm_safepoint();

  Universe::heap()->safepoint_synchronize_end();

  SafepointTracing::end();

  post_safepoint_end_event(event, safepoint_id());
}

Configuration enabled threshold
profiling false 0 ms
default false 10 ms

Field Type Description
safepointId ulong Safepoint Identifier

Examples 3
safepointId ulong
1530
startTime long: millis
309645092835
safepointId ulong
1219
startTime long: millis
411384191398
safepointId ulong
767
startTime long: millis
431546937489

ExecuteVMOperation

profiling default startTime duration eventThread 11 17 21 25 26 27 graal vm

Category: Java Virtual Machine / Runtime

Execution of a VM Operation

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/vmThread.cpp:

  // Wait until VM thread is terminated
  // Note: it should be OK to use Terminator_lock here. But this is called
  // at a very delicate time (VM shutdown) and we are operating in non- VM
  // thread at Safepoint. It's safer to not share lock with other threads.
  {
    MonitorLocker ml(_terminate_lock, Mutex::_no_safepoint_check_flag);
    while (!VMThread::is_terminated()) {
      ml.wait();
    }
  }
}

static void post_vm_operation_event(EventExecuteVMOperation* event, VM_Operation* op) {
  assert(event != nullptr, "invariant");
  assert(op != nullptr, "invariant");
  const bool evaluate_at_safepoint = op->evaluate_at_safepoint();
  event->set_operation(op->type());
  event->set_safepoint(evaluate_at_safepoint);
  event->set_blocking(true);
  event->set_caller(JFR_THREAD_ID(op->calling_thread()));
  event->set_safepointId(evaluate_at_safepoint ? SafepointSynchronize::safepoint_id() : 0);
  event->commit();
}

void VMThread::evaluate_operation(VM_Operation* op) {
  ResourceMark rm;

  {
    PerfTraceTime vm_op_timer(perf_accumulated_vm_operation_time());
    HOTSPOT_VMOPS_BEGIN(
                     (char *) op->name(), strlen(op->name()),
                     op->evaluate_at_safepoint() ? 0 : 1);

    EventExecuteVMOperation event;
    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);
  }

  if (UsePerfData && os::is_thread_cpu_time_supported()) {

Configuration enabled threshold
profiling true 0 ms
default true 10 ms

Field Type Description
operation VMOperationType Operation
safepoint boolean At Safepoint If the operation occurred at a safepoint
blocking boolean Caller Blocked If the calling thread was blocked until the operation was complete
caller Thread Caller Thread requesting operation. If non-blocking, will be set to 0 indicating thread is unknown
safepointId ulong Safepoint Identifier The safepoint (if any) under which this operation was completed

Examples 3
blocking boolean
true
caller Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Executor task launch worker for task 4.0 in stage 18.0 (TID 111)
javaThreadId long
1153
osName string
Executor task launch worker for task 4.0 in stage 18.0 (TID 111)
osThreadId long
3765
virtual boolean
false
operation VMOperationType
G1TryInitiateConcMark
safepoint boolean
true
safepointId ulong
1540
startTime long: millis
311688916280
blocking boolean
true
caller Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
JFR Periodic Tasks
javaThreadId long
14
osName string
JFR Periodic Tasks
osThreadId long
2332
virtual boolean
false
operation VMOperationType
GC_HeapInspection
safepoint boolean
true
safepointId ulong
1248
startTime long: millis
453268516111
blocking boolean
true
caller Thread
group ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
JFR Recorder Thread
javaThreadId long
14
osName string
JFR Recorder Thread
osThreadId long
2308
virtual boolean
false
operation VMOperationType
JFRSafepointWrite
safepoint boolean
true
safepointId ulong
682
startTime long: millis
349228536123

Shutdown

profiling default startTime eventThread stackTrace 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime

JVM shutting down

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/threads.cpp:

  // Wait until we are the last non-daemon thread to execute, or
  // if we are a daemon then wait until the last non-daemon thread has
  // executed.
  bool daemon = java_lang_Thread::is_daemon(thread->threadObj());
  int expected = daemon ? 0 : 1;
  {
    MonitorLocker nu(Threads_lock);
    while (Threads::number_of_non_daemon_threads() > expected)
      // This wait should make safepoint checks, wait without a timeout.
      nu.wait(0);
  }

  EventShutdown e;
  if (e.should_commit()) {
    e.set_reason("No remaining non-daemon Java threads");
    e.commit();
  }

  // Hang forever on exit if we are reporting an error.
  if (ShowMessageBoxOnError && VMError::is_error_reported()) {
    os::infinite_sleep();
  }
  os::wait_for_keypress_at_exit();

src/hotspot/share/jfr/recorder/repository/jfrEmergencyDump.cpp:

  void transition_to_native() {
    if (_jt != nullptr) {
      assert(_jt->thread_state() == _thread_in_vm, "invariant");
      _jt->set_thread_state(_thread_in_native);
    }
  }
};

static void post_events(bool exception_handler, 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();
}

src/hotspot/share/prims/jvm.cpp:

JVM_ENTRY(jstring, JVM_GetTemporaryDirectory(JNIEnv *env))
  HandleMark hm(THREAD);
  const char* temp_dir = os::get_temp_directory();
  Handle h = java_lang_String::create_from_platform_dependent_str(temp_dir, CHECK_NULL);
  return (jstring) JNIHandles::make_local(THREAD, h());
JVM_END


// java.lang.Runtime /////////////////////////////////////////////////////////////////////////

extern volatile jint vm_created;

JVM_ENTRY_NO_ENV(void, JVM_BeforeHalt())
  EventShutdown event;
  if (event.should_commit()) {
    event.set_reason("Shutdown requested from Java");
    event.commit();
  }
JVM_END


JVM_ENTRY_NO_ENV(void, JVM_Halt(jint code))
  before_exit(thread, true);
  vm_exit(code);
JVM_END

Configuration enabled stackTrace
profiling true true
default true true

Field Type Description
reason string Reason Reason for JVM shutdown

Examples 3
reason string
No remaining non-daemon Java threads
stackTrace StackTrace
null
startTime long: millis
471414095831
reason string
No remaining non-daemon Java threads
stackTrace StackTrace
null
startTime long: millis
511318373210
reason string
No remaining non-daemon Java threads
stackTrace StackTrace
null
startTime long: millis
389613679294

SymbolTableStatistics

profiling default startTime duration every chunk 13 17 21 25 26 27

Category: Java Virtual Machine / Runtime / Tables

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  event.set_entryCount(statistics._number_of_entries);
  event.set_totalFootprint(statistics._total_footprint);
  event.set_bucketCountMaximum(statistics._maximum_bucket_size);
  event.set_bucketCountAverage(statistics._average_bucket_size);
  event.set_bucketCountVariance(statistics._variance_of_bucket_size);
  event.set_bucketCountStandardDeviation(statistics._stddev_of_bucket_size);
  event.set_insertionRate(statistics._add_rate);
  event.set_removalRate(statistics._remove_rate);
  event.commit();
}

TRACE_REQUEST_FUNC(SymbolTableStatistics) {
  TableStatistics statistics = SymbolTable::get_table_statistics();
  emit_table_statistics<EventSymbolTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(StringTableStatistics) {
  TableStatistics statistics = StringTable::get_table_statistics();
  emit_table_statistics<EventStringTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(CompilerStatistics) {
  EventCompilerStatistics event;
  event.set_compileCount(CompileBroker::get_total_compile_count());
  event.set_bailoutCount(CompileBroker::get_total_bailout_count());

Configuration enabled period
profiling true 10 s
default true 10 s

Field Type Description
bucketCount ulong Bucket Count Number of buckets
entryCount ulong Entry Count Number of all entries
totalFootprint ulong: bytes Total Footprint Total memory footprint (the table itself plus all of the entries)
bucketCountMaximum ulong Maximum Bucket Count The maximum bucket length (entries in a single bucket)
bucketCountAverage float Average Bucket Count The average bucket length
bucketCountVariance float Bucket Count Variance How far bucket lengths are spread out from their average value
bucketCountStandardDeviation float Bucket Count Standard Deviation How far bucket lengths are spread out from their mean (expected) value
insertionRate float Insertion Rate How many items were added since last event (per second)
removalRate float Removal Rate How many items were removed since last event (per second)

Examples 3
bucketCount ulong
131072
bucketCountAverage float
4.5954895
bucketCountMaximum ulong
17
bucketCountStandardDeviation float
2.1463
bucketCountVariance float
4.6066046
entryCount ulong
602340
insertionRate float
4869.7637
removalRate float
19.54551
startTime long: millis
372734661477
totalFootprint ulong: bytes
66907400
bucketCount ulong
65536
bucketCountAverage float
7.7863007
bucketCountMaximum ulong
21
bucketCountStandardDeviation float
2.7981353
bucketCountVariance float
7.8295617
entryCount ulong
510283
insertionRate float
238.55138
removalRate float
25.208181
startTime long: millis
429728271359
totalFootprint ulong: bytes
54975952
bucketCount ulong
131072
bucketCountAverage float
4.691452
bucketCountMaximum ulong
18
bucketCountStandardDeviation float
2.1653378
bucketCountVariance float
4.688688
entryCount ulong
614918
insertionRate float
1024.0675
removalRate float
4.647029
startTime long: millis
499538500217
totalFootprint ulong: bytes
67858360

StringTableStatistics

profiling default startTime duration every chunk 13 17 21 25 26 27

Category: Java Virtual Machine / Runtime / Tables

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  event.set_bucketCountStandardDeviation(statistics._stddev_of_bucket_size);
  event.set_insertionRate(statistics._add_rate);
  event.set_removalRate(statistics._remove_rate);
  event.commit();
}

TRACE_REQUEST_FUNC(SymbolTableStatistics) {
  TableStatistics statistics = SymbolTable::get_table_statistics();
  emit_table_statistics<EventSymbolTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(StringTableStatistics) {
  TableStatistics statistics = StringTable::get_table_statistics();
  emit_table_statistics<EventStringTableStatistics>(statistics);
}

TRACE_REQUEST_FUNC(CompilerStatistics) {
  EventCompilerStatistics event;
  event.set_compileCount(CompileBroker::get_total_compile_count());
  event.set_bailoutCount(CompileBroker::get_total_bailout_count());
  event.set_invalidatedCount(CompileBroker::get_total_invalidated_count());
  event.set_osrCompileCount(CompileBroker::get_total_osr_compile_count());
  event.set_standardCompileCount(CompileBroker::get_total_standard_compile_count());
  event.set_osrBytesCompiled(CompileBroker::get_sum_osr_bytes_compiled());
  event.set_standardBytesCompiled(CompileBroker::get_sum_standard_bytes_compiled());

Configuration enabled period
profiling true 10 s
default true 10 s

Field Type Description
bucketCount ulong Bucket Count Number of buckets
entryCount ulong Entry Count Number of all entries
totalFootprint ulong: bytes Total Footprint Total memory footprint (the table itself plus all of the entries)
bucketCountMaximum ulong Maximum Bucket Count The maximum bucket length (entries in a single bucket)
bucketCountAverage float Average Bucket Count The average bucket length
bucketCountVariance float Bucket Count Variance How far bucket lengths are spread out from their average value
bucketCountStandardDeviation float Bucket Count Standard Deviation How far bucket lengths are spread out from their mean (expected) value
insertionRate float Insertion Rate How many items were added since last event (per second)
removalRate float Removal Rate How many items were removed since last event (per second)

Examples 3
bucketCount ulong
65536
bucketCountAverage float
1.7398834
bucketCountMaximum ulong
9
bucketCountStandardDeviation float
1.309187
bucketCountVariance float
1.7139708
entryCount ulong
114025
insertionRate float
1004.1571
removalRate float
45.56368
startTime long: millis
372764437538
totalFootprint ulong: bytes
12690408
bucketCount ulong
65536
bucketCountAverage float
1.7169952
bucketCountMaximum ulong
10
bucketCountStandardDeviation float
1.304267
bucketCountVariance float
1.7011125
entryCount ulong
112525
insertionRate float
843.92676
removalRate float
23.042065
startTime long: millis
451554531422
totalFootprint ulong: bytes
12583776
bucketCount ulong
65536
bucketCountAverage float
1.7982788
bucketCountMaximum ulong
10
bucketCountStandardDeviation float
1.3266033
bucketCountVariance float
1.7598761
entryCount ulong
117852
insertionRate float
51.957638
removalRate float
11.546142
startTime long: millis
510647547601
totalFootprint ulong: bytes
12125984

ThreadDump

profiling default startTime duration every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

/*
 * This is left empty on purpose, having ExecutionSample as a requestable
 * is a way of getting the period. The period is passed to ThreadSampling::update_period.
 * Implementation in periodic/sampling/jfrThreadSampler.cpp.
 */
TRACE_REQUEST_FUNC(ExecutionSample) {
}
TRACE_REQUEST_FUNC(NativeMethodSample) {
}

TRACE_REQUEST_FUNC(ThreadDump) {
  ResourceMark rm;
  EventThreadDump event;
  event.set_result(JfrDcmdEvent::thread_dump());
  event.commit();
}

static int _native_library_callback(const char* name, address base, address top, void *param) {
  EventNativeLibrary event(UNTIMED);
  event.set_name(name);
  event.set_baseAddress((u8)base);
  event.set_topAddress((u8)top);
  event.set_starttime(*(JfrTicks*)param);
  event.set_endtime(*(JfrTicks*) param);

Configuration enabled period
profiling true 60 s
default true everyChunk

Field Type Description
result string Thread Dump

Examples 3
result string
2026-02-22 00:50:05 Full thread dump OpenJDK 64-Bit Server VM (21.0.10.0.1+1-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x00007fd7e8392870, length=180, elements={ 0x00007fd888057cf0, 0x00007fd888132130, 0x00007fd888133670, 0x00007fd888134dd0, 0x00007fd8881363e0, 0x00007fd88
startTime long: millis
411937040455
result string
2026-02-22 00:49:05 Full thread dump OpenJDK 64-Bit Server VM (21.0.10.0.1+1-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x00007fce50054530, length=136, elements={ 0x00007fcf20057d00, 0x00007fcf20196c30, 0x00007fcf201981a0, 0x00007fcf20199930, 0x00007fcf2019af70, 0x00007fcf2
startTime long: millis
352139743285
result string
2026-02-22 00:51:34 Full thread dump OpenJDK 64-Bit Server VM (21.0.10.0.1+1-LTS mixed mode, sharing): Threads class SMR info: _java_thread_list=0x00007f9fb0240480, length=51, elements={ 0x00007fa030057cd0, 0x00007fa0300ac8a0, 0x00007fa0300adde0, 0x00007fa0300af540, 0x00007fa0300b0b50, 0x00007fa030
startTime long: millis
487947087467

NativeLibrary

profiling default startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime

Information about a dynamic library or other native image loaded by the JVM process

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

TRACE_REQUEST_FUNC(ExecutionSample) {
}
TRACE_REQUEST_FUNC(NativeMethodSample) {
}

TRACE_REQUEST_FUNC(ThreadDump) {
  ResourceMark rm;
  EventThreadDump event;
  event.set_result(JfrDcmdEvent::thread_dump());
  event.commit();
}

static int _native_library_callback(const char* name, address base, address top, void *param) {
  EventNativeLibrary event(UNTIMED);
  event.set_name(name);
  event.set_baseAddress((u8)base);
  event.set_topAddress((u8)top);
  event.set_starttime(*(JfrTicks*)param);
  event.set_endtime(*(JfrTicks*) param);
  event.commit();
  return 0;
}

TRACE_REQUEST_FUNC(NativeLibrary) {
  JfrTicks ts= JfrTicks::now();

Configuration enabled period
profiling true everyChunk
default true everyChunk

Field Type Description
name string Name
baseAddress ulong: address Base Address Starting address of the module
topAddress ulong: address Top Address Ending address of the module, if available

Examples 3
baseAddress ulong: address
140326054395904
name string
/opt/hostedtoolcache/Java_SapMachine_jdk/21.0.10-0.1/x64/lib/server/libjvm.so
startTime long: millis
403519827831
topAddress ulong: address
140326077087744
baseAddress ulong: address
140568081072128
name string
/lib/x86_64-linux-gnu/libdl.so.2
startTime long: millis
367071309166
topAddress ulong: address
140568081092608
baseAddress ulong: address
140527728119808
name string
/lib/x86_64-linux-gnu/librt.so.1
startTime long: millis
303662272949
topAddress ulong: address
140527728140288

NativeLibraryLoad

profiling default startTime duration eventThread stackTrace 22 25 26 27

Category: Java Virtual Machine / Runtime

Information about a dynamic library or other native image load operation

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/support/jfrNativeLibraryLoadEvent.cpp:

/*
 * The JfrTicks value is heap allocated inside an object of type JfrTicksWrapper.
 * The reason is that a raw value object of type Ticks is not possible at this
 * location because this code runs as part of early VM bootstrap, at a moment
 * where Ticks support is not yet initialized.
 */
template <typename EventType>
static inline JfrTicksWrapper* allocate_start_time() {
  return EventType::is_enabled() ? new JfrTicksWrapper() : nullptr;
}

NativeLibraryLoadEvent::NativeLibraryLoadEvent(const char* name, void** result) : JfrNativeLibraryEventBase(name), _result(result) {
  assert(_result != nullptr, "invariant");
  _start_time = allocate_start_time<EventNativeLibraryLoad>();
}

bool NativeLibraryLoadEvent::success() const {
  return *_result != nullptr;
}

NativeLibraryUnloadEvent::NativeLibraryUnloadEvent(const char* name) : JfrNativeLibraryEventBase(name), _result(false) {
  _start_time = allocate_start_time<EventNativeLibraryUnload>();
}

bool NativeLibraryUnloadEvent::success() const {
  return _result;
}

src/hotspot/share/jfr/support/jfrNativeLibraryLoadEvent.cpp:

  event.set_errorMessage(helper.error_msg());
  event.set_success(helper.success());
  Thread* thread = Thread::current();
  assert(thread != nullptr, "invariant");
  if (thread->is_Java_thread()) {
    JavaThread* jt = JavaThread::cast(thread);
    if (jt->thread_state() != _thread_in_vm) {
      assert(jt->thread_state() == _thread_in_native, "invariant");
      // For a JavaThread to take a JFR stacktrace, it must be in _thread_in_vm. Can safepoint here.
      ThreadInVMfromNative transition(jt);
      event.commit();
      return;
    }
  }
  event.commit();
}

NativeLibraryLoadEvent::~NativeLibraryLoadEvent() {
  commit<EventNativeLibraryLoad>(*this);
}

NativeLibraryUnloadEvent::~NativeLibraryUnloadEvent() {
  commit<EventNativeLibraryUnload>(*this);
}

Configuration enabled stackTrace threshold
profiling true true 0 ms
default true true 0 ms

Field Type Description
name string Name
success boolean Success Success or failure of the load operation
errorMessage string Error Message In case of a load error, error description

NativeLibraryUnload

profiling default startTime duration eventThread stackTrace 22 25 26 27

Category: Java Virtual Machine / Runtime

Information about a dynamic library or other native image unload operation

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/support/jfrNativeLibraryLoadEvent.cpp:

static inline JfrTicksWrapper* allocate_start_time() {
  return EventType::is_enabled() ? new JfrTicksWrapper() : nullptr;
}

NativeLibraryLoadEvent::NativeLibraryLoadEvent(const char* name, void** result) : JfrNativeLibraryEventBase(name), _result(result) {
  assert(_result != nullptr, "invariant");
  _start_time = allocate_start_time<EventNativeLibraryLoad>();
}

bool NativeLibraryLoadEvent::success() const {
  return *_result != nullptr;
}

NativeLibraryUnloadEvent::NativeLibraryUnloadEvent(const char* name) : JfrNativeLibraryEventBase(name), _result(false) {
  _start_time = allocate_start_time<EventNativeLibraryUnload>();
}

bool NativeLibraryUnloadEvent::success() const {
  return _result;
}

void NativeLibraryUnloadEvent::set_result(bool result) {
  _result = result;
}

template <typename EventType, typename HelperType>
static void commit(HelperType& helper) {
  if (!helper.has_start_time()) {
    return;
  }
  EventType event(UNTIMED);
  event.set_endtime(JfrTicks::now());
  event.set_starttime(*helper.start_time());

src/hotspot/share/jfr/support/jfrNativeLibraryLoadEvent.cpp:

  event.set_errorMessage(helper.error_msg());
  event.set_success(helper.success());
  Thread* thread = Thread::current();
  assert(thread != nullptr, "invariant");
  if (thread->is_Java_thread()) {
    JavaThread* jt = JavaThread::cast(thread);
    if (jt->thread_state() != _thread_in_vm) {
      assert(jt->thread_state() == _thread_in_native, "invariant");
      // For a JavaThread to take a JFR stacktrace, it must be in _thread_in_vm. Can safepoint here.
      ThreadInVMfromNative transition(jt);
      event.commit();
      return;
    }
  }
  event.commit();
}

NativeLibraryLoadEvent::~NativeLibraryLoadEvent() {
  commit<EventNativeLibraryLoad>(*this);
}

NativeLibraryUnloadEvent::~NativeLibraryUnloadEvent() {
  commit<EventNativeLibraryUnload>(*this);
}

Configuration enabled stackTrace threshold
profiling true true 0 ms
default true true 0 ms

Field Type Description
name string Name
success boolean Success Success or failure of the unload operation
errorMessage string Error Message In case of an unload error, error description

ModuleRequire

profiling default startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime / Modules

A directed edge representing a dependency

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrModuleEvent.cpp:

   ModuleDependencyClosure(const ModuleEntry* module, EventFunc ef) : ModuleEventCallbackClosure(ef), _module(module) {}
   void do_module(ModuleEntry* entry);
};

class ModuleExportClosure : public ModuleEventCallbackClosure {
 private:
  const PackageEntry* const _package;
 public:
  ModuleExportClosure(const PackageEntry* pkg, EventFunc ef) : ModuleEventCallbackClosure(ef), _package(pkg) {}
  void do_module(ModuleEntry* entry);
};

static void write_module_dependency_event(const void* from_module, const ModuleEntry* to_module) {
  EventModuleRequire event(UNTIMED);
  event.set_starttime(invocation_time);
  event.set_endtime(invocation_time);
  event.set_source((const ModuleEntry*)from_module);
  event.set_requiredModule(to_module);
  event.commit();
}

static void write_module_export_event(const void* package, const ModuleEntry* qualified_export) {
  EventModuleExport event(UNTIMED);
  event.set_starttime(invocation_time);
  event.set_endtime(invocation_time);

Configuration enabled period
profiling true endChunk
default true endChunk

Field Type Description
source Module Source Module
requiredModule Module Required Module

Examples 3
requiredModule Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
source Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
jdk/internal/loader
location string
jrt:/jdk.editpad
name string
jdk.editpad
version string
21.0.10.0.1
startTime long: millis
299453566656
requiredModule Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.naming
name string
java.naming
version string
21.0.10.0.1
source Module
classLoader ClassLoader
name string
platform
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$PlatformClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
jdk/internal/loader
location string
jrt:/jdk.security.auth
name string
jdk.security.auth
version string
21.0.10.0.1
startTime long: millis
353956903209
requiredModule Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
source Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
jdk.proxy9
version string
null
startTime long: millis
399252294444

ModuleExport

profiling default startTime every chunk 11 17 21 25 26 27

Category: Java Virtual Machine / Runtime / Modules

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrModuleEvent.cpp:

  void do_module(ModuleEntry* entry);
};

static void write_module_dependency_event(const void* from_module, const ModuleEntry* to_module) {
  EventModuleRequire event(UNTIMED);
  event.set_starttime(invocation_time);
  event.set_endtime(invocation_time);
  event.set_source((const ModuleEntry*)from_module);
  event.set_requiredModule(to_module);
  event.commit();
}

static void write_module_export_event(const void* package, const ModuleEntry* qualified_export) {
  EventModuleExport event(UNTIMED);
  event.set_starttime(invocation_time);
  event.set_endtime(invocation_time);
  event.set_exportedPackage((const PackageEntry*)package);
  event.set_targetModule(qualified_export);
  event.commit();
}

void ModuleDependencyClosure::do_module(ModuleEntry* to_module) {
  assert_locked_or_safepoint(Module_lock);
  assert(to_module != nullptr, "invariant");
  assert(_module != nullptr, "invariant");

Configuration enabled period
profiling true endChunk
default true endChunk

Field Type Description
exportedPackage Package Exported Package
targetModule Module Target Module Module to which the package is qualifiedly exported. If null or N/A, the package is unqualifiedly exported

Examples 3
exportedPackage Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
com/fasterxml/jackson/module/scala/util
startTime long: millis
353957332822
targetModule Module
null
exportedPackage Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
jdk.proxy3
version string
null
name string
com/sun/proxy/jdk/proxy3
startTime long: millis
399252527639
targetModule Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
exportedPackage Package
exported boolean
true
module Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
jdk/internal/loader
location string
jrt:/jdk.internal.opt
name string
jdk.internal.opt
version string
21.0.10.0.1
name string
jdk/internal/opt
startTime long: millis
299453845968
targetModule Module
classLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
10
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
jdk/internal/loader
location string
jrt:/jdk.jartool
name string
jdk.jartool
version string
21.0.10.0.1

Java Application

ThreadStart

profiling default startTime eventThread stackTrace 11 17 21 25 26 27 graal vm

Category: Java Application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/support/jfrThreadLocal.cpp:

const JfrBlobHandle& JfrThreadLocal::thread_blob() const {
  return _thread;
}

static void send_java_thread_start_event(JavaThread* jt) {
  assert(jt != nullptr, "invariant");
  assert(Thread::current() == jt, "invariant");
  if (!JfrJavaSupport::on_thread_start(jt)) {
    // thread is excluded
    return;
  }
  EventThreadStart event;
  traceid thread_id = JfrThreadLocal::jvm_thread_id(jt);
  assert(thread_id != 0, "invariant");
  event.set_thread(thread_id);
  event.set_parentThread(jt->jfr_thread_local()->parent_thread_id());
  event.commit();
}

void JfrThreadLocal::on_start(Thread* t) {
  assign_thread_id(t, t->jfr_thread_local());
  if (JfrRecorder::is_recording()) {
    JfrCheckpointManager::write_checkpoint(t);

src/hotspot/share/jfr/support/jfrThreadLocal.cpp:

// The starter thread ensures that the startee has a valid _vm_thread_id and _contextual_id.
// This is to avoid recursion in thread assignment since accessing the java threadObj can lead
// to events being fired, a situation the starter thread can handle but not the startee.
void JfrThreadLocal::on_java_thread_start(JavaThread* starter, JavaThread* startee) {
  assert(starter != nullptr, "invariant");
  assert(startee != nullptr, "invariant");
  JfrThreadLocal* const tl = startee->jfr_thread_local();
  assign_thread_id(startee, tl);
  assert(vthread_id(startee) != 0, "invariant");
  assert(jvm_thread_id(startee) == vthread_id(startee), "invariant");
  if (JfrRecorder::is_recording() && EventThreadStart::is_enabled() && EventThreadStart::is_stacktrace_enabled()) {
    // skip level 2 to skip frames Thread.start() and Thread.start0()
    startee->jfr_thread_local()->set_cached_stack_trace_id(JfrStackTraceRepository::record(starter, 2));
  }
}

void JfrThreadLocal::release(Thread* t) {
  if (has_java_event_writer()) {
    assert(t->is_Java_thread(), "invariant");
    JfrJavaSupport::destroy_global_jni_handle(java_event_writer());
    _java_event_writer = nullptr;
  }

Configuration enabled stackTrace
profiling true true
default true true

Field Type Description
thread Thread New Java Thread
parentThread Thread Parent Java Thread

Examples 3
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-storage-async-thread-pool-63
javaThreadId long
1271
osName string
block-manager-storage-async-thread-pool-63
osThreadId long
3921
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
2
lineNumber int
2577
method Method
descriptor string
(Ljava/lang/Thread;Ljdk/internal/vm/ThreadContainer;)V
hidden boolean
false
modifiers int
1
name string
start
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/System$2
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
313486621651
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-storage-async-thread-pool-65
javaThreadId long
1273
osName string
block-manager-storage-async-thread-pool-65
osThreadId long
3923
virtual boolean
false
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
dispatcher-BlockManagerEndpoint1
javaThreadId long
1190
osName string
dispatcher-BlockManagerEndpoint1
osThreadId long
3829
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
2
lineNumber int
2577
method Method
descriptor string
(Ljava/lang/Thread;Ljdk/internal/vm/ThreadContainer;)V
hidden boolean
false
modifiers int
1
name string
start
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/System$2
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
354133172238
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-storage-async-thread-pool-42
javaThreadId long
1304
osName string
block-manager-storage-async-thread-pool-42
osThreadId long
3960
virtual boolean
false
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
dispatcher-BlockManagerEndpoint1
javaThreadId long
1169
osName string
dispatcher-BlockManagerEndpoint1
osThreadId long
3805
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
2
lineNumber int
2577
method Method
descriptor string
(Ljava/lang/Thread;Ljdk/internal/vm/ThreadContainer;)V
hidden boolean
false
modifiers int
1
name string
start
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
java/lang/System$2
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
405684622224
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-storage-async-thread-pool-48
javaThreadId long
1292
osName string
block-manager-storage-async-thread-pool-48
osThreadId long
3954
virtual boolean
false

ThreadEnd

profiling default startTime eventThread 11 17 21 25 26 27 graal vm

Category: Java Application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/java.cpp:

  // Actual shutdown logic begins here.

#if INCLUDE_JVMCI
  if (EnableJVMCI) {
    JVMCI::shutdown(thread);
  }
#endif

  // Hang forever on exit if we're reporting an error.
  if (ShowMessageBoxOnError && VMError::is_error_reported()) {
    os::infinite_sleep();
  }

  EventThreadEnd event;
  if (event.should_commit()) {
    event.set_thread(JFR_JVM_THREAD_ID(thread));
    event.commit();
  }

  JFR_ONLY(Jfr::on_vm_shutdown(false, halt);)

  // Stop the WatcherThread. We do this before disenrolling various
  // PeriodicTasks to reduce the likelihood of races.
  WatcherThread::stop();

src/hotspot/share/jfr/support/jfrThreadLocal.cpp:

  assert(t != nullptr, "invariant");
  assert(Thread::current() == t, "invariant");
  assert(!tl->is_dead(), "invariant");
  assert(tl->shelved_buffer() == nullptr, "invariant");
  tl->_dead = true;
  tl->release(t);
}

static void send_java_thread_end_event(JavaThread* jt, traceid tid) {
  assert(jt != nullptr, "invariant");
  assert(Thread::current() == jt, "invariant");
  assert(tid != 0, "invariant");
  if (JfrRecorder::is_recording()) {
    EventThreadEnd event;
    event.set_thread(tid);
    event.commit();
    ObjectSampleCheckpoint::on_thread_exit(tid);
  }
}

void JfrThreadLocal::on_exit(Thread* t) {
  assert(t != nullptr, "invariant");
  JfrThreadLocal * const tl = t->jfr_thread_local();
  assert(!tl->is_dead(), "invariant");
  if (JfrRecorder::is_recording()) {

Configuration enabled
profiling true
default true

Field Type Description
thread Thread Java Thread

Examples 3
startTime long: millis
396858677949
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-storage-async-thread-pool-11
javaThreadId long
1250
osName string
block-manager-storage-async-thread-pool-11
osThreadId long
3898
virtual boolean
false
startTime long: millis
335808186395
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
map-output-dispatcher-7
javaThreadId long
1119
osName string
map-output-dispatcher-7
osThreadId long
3725
virtual boolean
false
startTime long: millis
427107165085
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
ForkJoinPool.commonPool-worker-4
javaThreadId long
144
osName string
ForkJoinPool.commonPool-worker-4
osThreadId long
2484
virtual boolean
false

ThreadPark

profiling default startTime duration eventThread stackTrace 11 17 21 25 26 27 graal vm

Category: Java Application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/prims/unsafe.cpp:

UNSAFE_ENTRY_SCOPED(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_SCOPED(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 != nullptr, "invariant");
  event->set_parkedClass((obj != nullptr) ? obj->klass() : nullptr);
  event->set_timeout(timeout_nanos);
  event->set_until(until_epoch_millis);
  event->set_address((obj != nullptr) ? (u8)cast_from_oop<uintptr_t>(obj) : 0);
  event->commit();
}

UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time)) {
  HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time);
  EventThreadPark event;

  JavaThreadParkedState jtps(thread, time != 0);
  thread->parker()->park(isAbsolute != 0, time);
  if (event.should_commit()) {
    const oop obj = thread->current_park_blocker();
    if (time == 0) {
      post_thread_park_event(&event, obj, min_jlong, min_jlong);
    } else {
      if (isAbsolute != 0) {
        post_thread_park_event(&event, obj, min_jlong, time);
      } else {

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Field Type Description
parkedClass Class Class Parked On
timeout long: nanos Park Timeout
until long: epochmillis Park Until
address ulong: address Address of Object Parked

Examples 3
address ulong: address
30318662192
parkedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionObject
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/util/concurrent/locks
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
jdk/internal/misc
type FrameType
Native
truncated boolean
false
startTime long: millis
299173787040
timeout long: nanos
99999920
until long: epochmillis
-9223372036854775808
address ulong: address
30344710256
parkedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionObject
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/util/concurrent/locks
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
jdk/internal/misc
type FrameType
Native
truncated boolean
false
startTime long: millis
339997310380
timeout long: nanos
9384998273
until long: epochmillis
-9223372036854775808
address ulong: address
31740000440
parkedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionObject
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/util/concurrent/locks
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/misc/Unsafe
package Package
exported boolean
true
module Module
classLoader ClassLoader
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jrt:/java.base
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type FrameType
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startTime long: millis
391571693643
timeout long: nanos
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until long: epochmillis
-9223372036854775808

JavaMonitorEnter

profiling default startTime duration eventThread stackTrace 11 17 21 25 26 27 graal vm

Category: Java Application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/objectMonitor.cpp:

    // above lost the race to async deflation. Undo the work and
    // force the caller to retry.
    const oop l_object = object();
    if (l_object != nullptr) {
      // 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(JfrConditionalFlush<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 = nullptr;

#if INCLUDE_JFR
  // get the owner's thread id for the MonitorEnter event
  // if it is enabled and the thread isn't suspended
  if (not_suspended && EventJavaMonitorEnter::is_enabled()) {
    _previous_owner_tid = JFR_THREAD_ID(current);
  }
#endif

  for (;;) {
    assert(current == owner_raw(), "invariant");

    // Drop the lock.
    // release semantics: prior loads and stores from within the critical section
    // must not float (reorder) past the following store that drops the lock.
    // Uses a storeload to separate release_store(owner) from the

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Field Type Description
monitorClass Class Monitor Class
previousOwner Thread Previous Monitor Owner
address ulong: address Monitor Address

Examples 3
address ulong: address
140525088909200
monitorClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
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bootstrap
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null
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1
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java/net/URLClassLoader
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exported boolean
true
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classLoader ClassLoader
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bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
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21.0.10.0.1
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org/apache/spark/scheduler/TaskSchedulerImpl
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java/net/URLClassLoader
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bootstrap
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null
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jrt:/java.base
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java.base
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21.0.10.0.1
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null
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org/apache/spark/scheduler
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dispatcher-event-loop-0
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1108
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304655120624
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140565892152880
monitorClass Class
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null
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java/util/HashMap
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null
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Executor task launch worker for task 7.0 in stage 18.0 (TID 114)
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Executor task launch worker for task 7.0 in stage 18.0 (TID 114)
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397847121766
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140323092540336
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null
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1
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java/util/HashMap
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21.0.10.0.1
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previousOwner Thread
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javaName string
Executor task launch worker for task 3.0 in stage 16.0 (TID 90)
javaThreadId long
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Executor task launch worker for task 3.0 in stage 16.0 (TID 90)
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3878
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(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/util/Map;Ljava/util/Map;Ljava/lang/invoke/SerializedLambda;)Ljava/lang/Object;
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startTime long: millis
442347681265

JavaMonitorWait

profiling default startTime duration eventThread stackTrace 11 17 21 25 26 27 graal vm

Category: Java Application

Waiting on a Java monitor

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/objectMonitor.cpp:

    _recursions = 0;
    return true;
  }
  THROW_MSG_(vmSymbols::java_lang_IllegalMonitorStateException(),
             "current thread is not owner", false);
}

static inline bool is_excluded(const Klass* monitor_klass) {
  assert(monitor_klass != nullptr, "invariant");
  NOT_JFR_RETURN_(false);
  JFR_ONLY(return vmSymbols::jfr_chunk_rotation_monitor() == monitor_klass->name());
}

static void post_monitor_wait_event(EventJavaMonitorWait* event,
                                    ObjectMonitor* monitor,
                                    uint64_t notifier_tid,
                                    jlong timeout,
                                    bool timedout) {
  assert(event != nullptr, "invariant");
  assert(monitor != nullptr, "invariant");
  const Klass* monitor_klass = monitor->object()->klass();
  if (is_excluded(monitor_klass)) {
    return;
  }
  event->set_monitorClass(monitor_klass);

src/hotspot/share/runtime/objectMonitor.cpp:

// -----------------------------------------------------------------------------
// Wait/Notify/NotifyAll
//
// Note: a subset of changes to ObjectMonitor::wait()
// will need to be replicated in complete_exit
void ObjectMonitor::wait(jlong millis, bool interruptible, TRAPS) {
  JavaThread* current = THREAD;

  assert(InitDone, "Unexpectedly not initialized");

  CHECK_OWNER();  // Throws IMSE if not owner.

  EventJavaMonitorWait event;

  // check for a pending interrupt
  if (interruptible && current->is_interrupted(true) && !HAS_PENDING_EXCEPTION) {
    // post monitor waited event.  Note that this is past-tense, we are done waiting.
    if (JvmtiExport::should_post_monitor_waited()) {
      // Note: 'false' parameter is passed here because the
      // wait was not timed out due to thread interrupt.
      JvmtiExport::post_monitor_waited(current, this, false);

      // In this short circuit of the monitor wait protocol, the
      // current thread never drops ownership of the monitor and

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Field Type Description
monitorClass Class Monitor Class Class of object waited on
notifier Thread Notifier Thread Notifying Thread
timeout long: millis Timeout Maximum wait time
timedOut boolean Timed Out Wait has been timed out
address ulong: address Monitor Address Address of object waited on

Examples 3
address ulong: address
140523009191568
monitorClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
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org/renaissance/twitter/finagle/FinagleChirper$Client
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true
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null
type Class
classLoader ClassLoader
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bootstrap
type Class
null
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false
modifiers int
1
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java/net/URLClassLoader
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exported boolean
true
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classLoader ClassLoader
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bootstrap
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null
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jrt:/java.base
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java.base
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21.0.10.0.1
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java/net
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null
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org/renaissance/twitter/finagle
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Thread-295
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Thread-295
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java/lang/Object
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Executor task launch worker-0
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433611356991
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java/lang/Object
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JavaMonitorInflate

profiling startTime duration eventThread stackTrace 11 17 21 25 26 27 graal vm

Category: Java Application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/runtime/synchronizer.cpp:

  if (!ret_code) {
    log_info(monitorinflation)("Async Deflation DID NOT happen after %d checks.", N_CHECKS);
  }

  return ret_code;
}

jlong ObjectSynchronizer::time_since_last_async_deflation_ms() {
  return (os::javaTimeNanos() - last_async_deflation_time_ns()) / (NANOUNITS / MILLIUNITS);
}

static void post_monitor_inflate_event(EventJavaMonitorInflate* event,
                                       const oop obj,
                                       ObjectSynchronizer::InflateCause cause) {
  assert(event != nullptr, "invariant");
  event->set_monitorClass(obj->klass());
  event->set_address((uintptr_t)(void*)obj);
  event->set_cause((u1)cause);
  event->commit();
}

// Fast path code shared by multiple functions
void ObjectSynchronizer::inflate_helper(oop obj) {
  markWord mark = obj->mark_acquire();
  if (mark.has_monitor()) {
    ObjectMonitor* monitor = mark.monitor();
    markWord dmw = monitor->header();
    assert(dmw.is_neutral(), "sanity check: header=" INTPTR_FORMAT, dmw.value());
    return;
  }
  (void)inflate(Thread::current(), obj, inflate_cause_vm_internal);
}

ObjectMonitor* ObjectSynchronizer::inflate(Thread* current, oop object,
                                           const InflateCause cause) {
  EventJavaMonitorInflate event;

  for (;;) {
    const markWord mark = object->mark_acquire();

    // The mark can be in one of the following states:
    // *  inflated     - Just return if using stack-locking.
    //                   If using fast-locking and the ObjectMonitor owner
    //                   is anonymous and the current thread owns the
    //                   object lock, then we make the current thread the
    //                   ObjectMonitor owner and remove the lock from the
    //                   current thread's lock stack.

Configuration enabled stackTrace threshold
profiling true true 10 ms
default false true 20 ms

Field Type Description
monitorClass Class Monitor Class
address ulong: address Monitor Address
cause InflateCause Monitor Inflation Cause Cause of inflation

ObjectAllocationInNewTLAB

startTime eventThread stackTrace 11 17 21 25 26 27 graal vm

Category: Java Application

Allocation in new Thread Local Allocation Buffer

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/allocTracer.cpp:

void AllocTracer::send_allocation_outside_tlab(Klass* klass, HeapWord* obj, size_t alloc_size, JavaThread* thread) {
  JFR_ONLY(JfrAllocationTracer tracer(klass, obj, alloc_size, true, thread);)
  EventObjectAllocationOutsideTLAB event;
  if (event.should_commit()) {
    event.set_objectClass(klass);
    event.set_allocationSize(alloc_size);
    event.commit();
  }
}

void AllocTracer::send_allocation_in_new_tlab(Klass* klass, HeapWord* obj, size_t tlab_size, size_t alloc_size, JavaThread* thread) {
  JFR_ONLY(JfrAllocationTracer tracer(klass, obj, alloc_size, false, thread);)
  EventObjectAllocationInNewTLAB event;
  if (event.should_commit()) {
    event.set_objectClass(klass);
    event.set_allocationSize(alloc_size);
    event.set_tlabSize(tlab_size);
    event.commit();
  }
}

void AllocTracer::send_allocation_requiring_gc_event(size_t size, uint gcId) {
  EventAllocationRequiringGC event;
  if (event.should_commit()) {

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
objectClass Class Object Class Class of allocated object
allocationSize ulong: bytes Allocation Size
tlabSize ulong: bytes TLAB Size

Examples 3
allocationSize ulong: bytes
48
objectClass Class
classLoader ClassLoader
name string
bootstrap
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null
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java/util/HashMap
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jrt:/java.base
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351651955823
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1041
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398882592013
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ObjectAllocationOutsideTLAB

startTime eventThread stackTrace 11 17 21 25 26 27

Category: Java Application

Allocation outside Thread Local Allocation Buffers

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/gc/shared/allocTracer.cpp:

#if INCLUDE_JFR
#include "jfr/support/jfrAllocationTracer.hpp"
#endif

void AllocTracer::send_allocation_outside_tlab(Klass* klass, HeapWord* obj, size_t alloc_size, JavaThread* thread) {
  JFR_ONLY(JfrAllocationTracer tracer(klass, obj, alloc_size, true, thread);)
  EventObjectAllocationOutsideTLAB event;
  if (event.should_commit()) {
    event.set_objectClass(klass);
    event.set_allocationSize(alloc_size);
    event.commit();
  }
}

void AllocTracer::send_allocation_in_new_tlab(Klass* klass, HeapWord* obj, size_t tlab_size, size_t alloc_size, JavaThread* thread) {
  JFR_ONLY(JfrAllocationTracer tracer(klass, obj, alloc_size, false, thread);)
  EventObjectAllocationInNewTLAB event;
  if (event.should_commit()) {
    event.set_objectClass(klass);

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
objectClass Class Object Class Class of allocated object
allocationSize ulong: bytes Allocation Size

Examples 3
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ObjectAllocationSample

throttle profiling default startTime eventThread stackTrace 16 17 21 25 26 27

Category: Java Application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/support/jfrObjectAllocationSample.cpp:

inline bool send_allocation_sample(const Klass* klass, int64_t allocated_bytes, JfrThreadLocal* tl) {
  EventObjectAllocationSample event;
  if (event.should_commit()) {
    const int64_t weight = allocated_bytes - tl->last_allocated_bytes();
    assert(weight > 0, "invariant");
    event.set_objectClass(klass);
    event.set_weight(weight);
    event.commit();
    tl->set_last_allocated_bytes(allocated_bytes);
    return true;
  }
  return false;
}

inline int64_t estimate_tlab_size_bytes(Thread* thread) {
  const size_t desired_tlab_size_bytes = thread->tlab().desired_size() * HeapWordSize;

Configuration enabled stackTrace throttle
profiling true true 300/s
default true true 150/s

Field Type Description
objectClass Class Object Class Class of allocated object
weight long: bytes Sample Weight The relative weight of the sample. Aggregating the weights for a large number of samples, for a particular class, thread or stack trace, gives a statistically accurate representation of the allocation pressure

Examples 3
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FileForce

profiling default startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/FileForceEvent.java

Category: Java Application

Force updates to be written to file

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/EventConfigurations.java:

package jdk.jfr.events;
import jdk.jfr.internal.JVMSupport;
import jdk.jfr.internal.event.EventConfiguration;

public final class EventConfigurations {
    public static final EventConfiguration FILE_READ = JVMSupport.getConfiguration(FileReadEvent.class);
    public static final EventConfiguration FILE_WRITE = JVMSupport.getConfiguration(FileWriteEvent.class);
    public static final EventConfiguration FILE_FORCE = JVMSupport.getConfiguration(FileForceEvent.class);
}

src/jdk.jfr/share/classes/jdk/jfr/events/FileForceEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "FileForce")
@Label("File Force")
@Category("Java Application")
@Description("Force updates to be written to file")
public final class FileForceEvent extends AbstractJDKEvent {

    // The order of these fields must be the same as the parameters in
    // commit(..., String, boolean)

    @Label("Path")
    @Description("Full path of the file")
    public String path;

    @Label("Update Metadata")
    @Description("Whether the file metadata is updated")
    public boolean metaData;

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileChannelImplInstrumentor.java:

    public void force(boolean metaData) throws IOException {
        EventConfiguration eventConfiguration = EventConfigurations.FILE_FORCE;
        if (!eventConfiguration.isEnabled()) {
            force(metaData);
            return;
        }
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            force(metaData);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileForceEvent.commit(start, duration, path, metaData);
            }
        }
    }

    @JIInstrumentationMethod
    public int read(ByteBuffer dst) throws IOException {
        EventConfiguration eventConfiguration = EventConfigurations.FILE_READ;
        if (!eventConfiguration.isEnabled()) {
            return read(dst);
        }
        int bytesRead = 0;

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

public final class JDKEvents {

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        // jdk.internal.event.* classes need their mirror
        // event class to be listed in the MirrorEvents class.
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ErrorThrownEvent.class,
        jdk.internal.event.ExceptionStatisticsEvent.class,

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Field Type Description
path string Path Full path of the file
metaData boolean Update Metadata Whether the file metadata is updated

VirtualThreadStart

startTime duration stackTrace 19 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/VirtualThreadStartEvent.java

Category: Java Application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/VirtualThreadStartEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.MirrorEvent;
import jdk.jfr.internal.RemoveFields;

@Category("Java Application")
@Label("Virtual Thread Start")
@Name("jdk.VirtualThreadStart")
@MirrorEvent(className = "jdk.internal.event.VirtualThreadStartEvent")
@RemoveFields("duration")
public final class VirtualThreadStartEvent extends AbstractJDKEvent {

    @Label("Thread Id")
    public long javaThreadId;

}

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

public final class MirrorEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class,
        ErrorThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ExceptionThrownEvent.class,
    };

    private static final Map<String, Class<? extends Event>> mirrorLookup = createLookup();

src/java.base/share/classes/jdk/internal/event/VirtualThreadStartEvent.java:

package jdk.internal.event;

/**
 * Event recording that a virtual thread has been started.
 */
public class VirtualThreadStartEvent extends Event {
    private final static VirtualThreadStartEvent EVENT = new VirtualThreadStartEvent();

    /**
     * Returns {@code true} if event is enabled, {@code false} otherwise.
     */
    public static boolean isTurnedOn() {
        return EVENT.isEnabled();
    }

    public long javaThreadId;
}

src/java.base/share/classes/java/lang/VirtualThread.java:

    /**
     * Runs a task in the context of this virtual thread.
     */
    private void run(Runnable task) {
        assert Thread.currentThread() == this && state == RUNNING;

        // notify JVMTI, may post VirtualThreadStart event
        notifyJvmtiStart();

        // emit JFR event if enabled
        if (VirtualThreadStartEvent.isTurnedOn()) {
            var event = new VirtualThreadStartEvent();
            event.javaThreadId = threadId();
            event.commit();
        }

        Object bindings = Thread.scopedValueBindings();
        try {
            runWith(bindings, task);
        } catch (Throwable exc) {
            dispatchUncaughtException(exc);
        } finally {
            try {

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
javaThreadId long Thread Id

SocketRead

profiling default startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/SocketReadEvent.java

Category: Java Application

Reading data from a socket

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/SocketReadEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "SocketRead")
@Label("Socket Read")
@Category("Java Application")
@Description("Reading data from a socket")
@MirrorEvent(className = "jdk.internal.event.SocketReadEvent")
public final class SocketReadEvent extends AbstractJDKEvent {

    @Label("Remote Host")
    public String host;

    @Label("Remote Address")
    public String address;

    @Label("Remote Port")
    public int port;

    @Label("Timeout Value")

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

public final class MirrorEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class,
        ErrorThrownEvent.class,
        ExceptionStatisticsEvent.class,

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

public final class JDKEvents {

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        // jdk.internal.event.* classes need their mirror
        // event class to be listed in the MirrorEvents class.
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ErrorThrownEvent.class,
        jdk.internal.event.ExceptionStatisticsEvent.class,
        jdk.internal.event.ExceptionThrownEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,

src/java.base/share/classes/sun/nio/ch/SocketChannelImpl.java:

            readLock.unlock();
        }
    }

    @Override
    public int read(ByteBuffer buf) throws IOException {
        if (!SocketReadEvent.enabled()) {
            return implRead(buf);
        }
        long start = SocketReadEvent.timestamp();
        int nbytes = implRead(buf);
        SocketReadEvent.offer(start, nbytes, remoteAddress(), 0);
        return nbytes;
    }


    @Override
    public long read(ByteBuffer[] dsts, int offset, int length)
        throws IOException
    {
        if (!SocketReadEvent.enabled()) {
            return implRead(dsts, offset, length);
        }
        long start = SocketReadEvent.timestamp();
        long nbytes = implRead(dsts, offset, length);
        SocketReadEvent.offer(start, nbytes, remoteAddress(), 0);
        return nbytes;
    }

    /**

src/java.base/share/classes/sun/nio/ch/SocketInputStream.java:

    private int implRead(byte[] b, int off, int len, int timeout) throws IOException {
        if (timeout > 0) {
            long nanos = MILLISECONDS.toNanos(timeout);
            return sc.blockingRead(b, off, len, nanos);
        } else {
            return sc.blockingRead(b, off, len, 0);
        }
    }

    @Override
    public int read(byte[] b, int off, int len) throws IOException {
        int timeout = timeoutSupplier.getAsInt();
        if (!SocketReadEvent.enabled()) {
            return implRead(b, off, len, timeout);
        }
        long start = SocketReadEvent.timestamp();
        int n = implRead(b, off, len, timeout);
        SocketReadEvent.offer(start, n, sc.remoteAddress(), timeout);
        return n;
    }

    @Override
    public int available() throws IOException {
        return sc.available();
    }

    @Override
    public void close() throws IOException {

src/java.base/share/classes/jdk/internal/event/SocketReadEvent.java:

/**
 * A JFR event for socket read operations.  This event is mirrored in
 * {@code jdk.jfr.events.SocketReadEvent } where the metadata for the event is
 * provided with annotations.  Some of the methods are replaced by generated
 * methods when jfr is enabled.  Note that the order of the arguments of the
 * {@link #commit(long, long, String, String, int, long, long, boolean)} method
 * must be the same as the order of the fields.
 */
public class SocketReadEvent extends Event {

    // THE ORDER OF THE FOLLOWING FIELDS IS IMPORTANT!
    // The order must match the argument order of the generated commit method.
    public String host;
    public String address;
    public int port;
    public long timeout;
    public long bytesRead;
    public boolean endOfStream;

    /**

src/java.base/share/classes/java/net/Socket.java:

        public int read() throws IOException {
            byte[] a = new byte[1];
            int n = read(a, 0, 1);
            return (n > 0) ? (a[0] & 0xff) : -1;
        }
        @Override
        public int read(byte[] b, int off, int len) throws IOException {
            if (!SocketReadEvent.enabled()) {
                return implRead(b, off, len);
            }
            long start = SocketReadEvent.timestamp();
            int nbytes = implRead(b, off, len);
            long duration = SocketReadEvent.timestamp() - start;
            if (SocketReadEvent.shouldCommit(duration)) {
                SocketReadEvent.emit(start, duration, nbytes, parent.getRemoteSocketAddress(), getSoTimeout());
            }
            return nbytes;
        }

        private int implRead(byte[] b, int off, int len) throws IOException {
            try {

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Field Type Description
host string Remote Host
address string Remote Address
port int Remote Port
timeout long: millis Timeout Value
bytesRead long: bytes Bytes Read Number of bytes read from the socket
endOfStream boolean End of Stream If end of stream was reached

ThreadSleep

profiling default startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ThreadSleepEvent.java

Category: Java Application

Excludes in stack trace: java.lang.Thread::afterSleep, java.lang.Thread::sleepNanos, java.lang.Thread::sleep

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/ThreadSleepEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.Timespan;
import jdk.jfr.internal.MirrorEvent;

@Category("Java Application")
@Label("Java Thread Sleep")
@Name("jdk.ThreadSleep")
@MirrorEvent(className = "jdk.internal.event.ThreadSleepEvent")
@StackFilter({"java.lang.Thread::afterSleep",
              "java.lang.Thread::sleepNanos",
              "java.lang.Thread::sleep"})
public final class ThreadSleepEvent extends AbstractJDKEvent {
    @Label("Sleep Time")
    @Timespan(Timespan.NANOSECONDS)
    public long time;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

public final class MirrorEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class,
        ErrorThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ExceptionThrownEvent.class,
    };

src/java.base/share/classes/jdk/internal/event/ThreadSleepEvent.java:

package jdk.internal.event;

/**
 * Event recording thread sleeping.
 */

public final class ThreadSleepEvent extends Event {
    private static final ThreadSleepEvent EVENT = new ThreadSleepEvent();

    /**
     * Returns {@code true} if event is enabled, {@code false} otherwise.
     */
    public static boolean isTurnedOn() {
        return EVENT.isEnabled();
    }

    public long time;
}

src/java.base/share/classes/java/lang/Thread.java:

        } else {
            yield0();
        }
    }

    private static native void yield0();

    /**
     * Called before sleeping to create a jdk.ThreadSleep event.
     */
    private static ThreadSleepEvent beforeSleep(long nanos) {
        ThreadSleepEvent event = null;
        if (ThreadSleepEvent.isTurnedOn()) {
            try {
                event = new ThreadSleepEvent();
                event.time = nanos;
                event.begin();
            } catch (OutOfMemoryError e) {
                event = null;
            }
        }
        return event;
    }

    /**
     * Called after sleeping to commit the jdk.ThreadSleep event.
     */
    private static void afterSleep(ThreadSleepEvent event) {
        if (event != null) {
            try {
                event.commit();
            } catch (OutOfMemoryError e) {
                // ignore
            }
        }
    }

    /**
     * Sleep for the specified number of nanoseconds, subject to the precision
     * and accuracy of system timers and schedulers.
     */
    private static void sleepNanos(long nanos) throws InterruptedException {
        ThreadSleepEvent event = beforeSleep(nanos);
        try {
            if (currentThread() instanceof VirtualThread vthread) {
                vthread.sleepNanos(nanos);
            } else {
                sleepNanos0(nanos);
            }
        } finally {
            afterSleep(event);
        }

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Field Type Description
time long: nanos Sleep Time

Examples 3
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
5
lineNumber int
474
method Method
descriptor string
(Ljdk/internal/event/ThreadSleepEvent;)V
hidden boolean
false
modifiers int
10
name string
afterSleep
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Thread
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
392168512940
time long: nanos
10000000
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
5
lineNumber int
474
method Method
descriptor string
(Ljdk/internal/event/ThreadSleepEvent;)V
hidden boolean
false
modifiers int
10
name string
afterSleep
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Thread
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
295244746371
time long: nanos
10000000
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
5
lineNumber int
474
method Method
descriptor string
(Ljdk/internal/event/ThreadSleepEvent;)V
hidden boolean
false
modifiers int
10
name string
afterSleep
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Thread
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
349791086277
time long: nanos
10000000

JavaErrorThrow

profiling default startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ErrorThrownEvent.java

Category: Java Application

An object derived from java.lang.Error has been created. OutOfMemoryErrors are ignored

Configuration enabled stackTrace
profiling true true
default true true

Field Type Description
message string Message
thrownClass Class Class

Examples 3
message string
static Lorg/apache/spark/ml/classification/LogisticRegression;.<clinit>()V
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
68
method Method
descriptor string
(Ljava/lang/String;)V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Error
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
433429434252
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/NoSuchMethodError
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
message string
static Lorg/apache/spark/storage/StorageLevel;.<clinit>()V
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
68
method Method
descriptor string
(Ljava/lang/String;)V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Error
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Inlined
truncated boolean
true
startTime long: millis
466398297769
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/NoSuchMethodError
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
message string
static Ljava/lang/Object;.<clinit>()V
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
68
method Method
descriptor string
(Ljava/lang/String;)V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Error
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Inlined
truncated boolean
true
startTime long: millis
349625427806
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/NoSuchMethodError
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang

VirtualThreadEnd

startTime duration stackTrace 19 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/VirtualThreadEndEvent.java

Category: Java Application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/VirtualThreadEndEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.MirrorEvent;
import jdk.jfr.internal.RemoveFields;

@Category("Java Application")
@Label("Virtual Thread End")
@Name("jdk.VirtualThreadEnd")
@MirrorEvent(className = "jdk.internal.event.VirtualThreadEndEvent")
@RemoveFields({"duration", "stackTrace"})
public final class VirtualThreadEndEvent extends AbstractJDKEvent {

    @Label("Thread Id")
    public long javaThreadId;

}

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

public final class MirrorEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class,
        ErrorThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ExceptionThrownEvent.class,
    };

    private static final Map<String, Class<? extends Event>> mirrorLookup = createLookup();

src/java.base/share/classes/jdk/internal/event/VirtualThreadEndEvent.java:

package jdk.internal.event;

/**
 * Event recording that a virtual thread has terminated.
 */
public class VirtualThreadEndEvent extends Event {
    private final static VirtualThreadEndEvent EVENT = new VirtualThreadEndEvent();

    /**
     * Returns {@code true} if event is enabled, {@code false} otherwise.
     */
    public static boolean isTurnedOn() {
        return EVENT.isEnabled();
    }

    public long javaThreadId;
}

src/java.base/share/classes/java/lang/VirtualThread.java:

        Object bindings = Thread.scopedValueBindings();
        try {
            runWith(bindings, task);
        } catch (Throwable exc) {
            dispatchUncaughtException(exc);
        } finally {
            try {
                // pop any remaining scopes from the stack, this may block
                StackableScope.popAll();

                // emit JFR event if enabled
                if (VirtualThreadEndEvent.isTurnedOn()) {
                    var event = new VirtualThreadEndEvent();
                    event.javaThreadId = threadId();
                    event.commit();
                }

            } finally {
                // notify JVMTI, may post VirtualThreadEnd event
                notifyJvmtiEnd();
            }
        }
    }

Configuration enabled
profiling false
default false

Field Type Description
javaThreadId long Thread Id

FileRead

profiling default startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/FileReadEvent.java

Category: Java Application

Appearing in: SerialGC, ZGC

Missing in: G1GC, ParallelGC, ShenandoahGC

Reading data from a file

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/EventConfigurations.java:

package jdk.jfr.events;
import jdk.jfr.internal.JVMSupport;
import jdk.jfr.internal.event.EventConfiguration;

public final class EventConfigurations {
    public static final EventConfiguration FILE_READ = JVMSupport.getConfiguration(FileReadEvent.class);
    public static final EventConfiguration FILE_WRITE = JVMSupport.getConfiguration(FileWriteEvent.class);
    public static final EventConfiguration FILE_FORCE = JVMSupport.getConfiguration(FileForceEvent.class);
}

src/jdk.jfr/share/classes/jdk/jfr/events/FileReadEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.DataAmount;
import jdk.jfr.Name;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "FileRead")
@Label("File Read")
@Category("Java Application")
@Description("Reading data from a file")
public final class FileReadEvent extends AbstractJDKEvent {

    // The order of these fields must be the same as the parameters in
    // commit(..., String, long, boolean)

    @Label("Path")
    @Description("Full path of the file, or N/A if a file descriptor was used to create the stream, for example System.in")
    public String path;

    @Label("Bytes Read")
    @Description("Number of bytes read from the file (possibly 0)")
    @DataAmount

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileInputStreamInstrumentor.java:

            if (result < 0) {
                endOfFile = true;
            } else {
                bytesRead = 1;
            }
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileReadEvent.commit(start, duration, path, bytesRead, endOfFile);
            }
        }
        return result;
    }

    @JIInstrumentationMethod
    public int read(byte b[]) throws IOException {

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileInputStreamInstrumentor.java:

        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            bytesRead = read(b);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                if (bytesRead < 0) {
                    FileReadEvent.commit(start, duration, path, 0L, true);
                } else {
                    FileReadEvent.commit(start, duration, path, bytesRead, false);
                }
            }
        }
        return bytesRead;
    }

    @JIInstrumentationMethod

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileInputStreamInstrumentor.java:

        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            bytesRead = read(b, off, len);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                if (bytesRead < 0) {
                    FileReadEvent.commit(start, duration, path, 0L, true);
                } else {
                    FileReadEvent.commit(start, duration, path, bytesRead, false);
                }
            }
        }
        return bytesRead;
    }
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/RandomAccessFileInstrumentor.java:

            if (result < 0) {
                endOfFile = true;
            } else {
                bytesRead = 1;
            }
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileReadEvent.commit(start, duration, path, bytesRead, endOfFile);
            }
        }
        return result;
    }

    @JIInstrumentationMethod
    public int read(byte b[]) throws IOException {

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/RandomAccessFileInstrumentor.java:

        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            bytesRead = read(b);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                if (bytesRead < 0) {
                    FileReadEvent.commit(start, duration, path, 0L, true);
                } else {
                    FileReadEvent.commit(start, duration, path, bytesRead, false);
                }
            }
        }
        return bytesRead;
    }

    @JIInstrumentationMethod

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/RandomAccessFileInstrumentor.java:

        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            bytesRead = read(b, off, len);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                if (bytesRead < 0) {
                    FileReadEvent.commit(start, duration, path, 0L, true);
                } else {
                    FileReadEvent.commit(start, duration, path, bytesRead, false);
                }
            }
        }
        return bytesRead;
    }

    @JIInstrumentationMethod

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileChannelImplInstrumentor.java:

        try {
            start = EventConfiguration.timestamp();
            bytesRead = read(dst);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                if (bytesRead < 0) {
                    FileReadEvent.commit(start, duration, path, 0L, true);
                } else {
                    FileReadEvent.commit(start, duration, path, bytesRead, false);
                }
            }
        }
        return bytesRead;
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileChannelImplInstrumentor.java:

        try {
            start = EventConfiguration.timestamp();
            bytesRead = read(dst, position);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                if (bytesRead < 0) {
                    FileReadEvent.commit(start, duration, path, 0L, true);
                } else {
                    FileReadEvent.commit(start, duration, path, bytesRead, false);
                }
            }
        }
        return bytesRead;
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileChannelImplInstrumentor.java:

        try {
            start = EventConfiguration.timestamp();
            bytesRead = read(dsts, offset, length);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                if (bytesRead < 0) {
                    FileReadEvent.commit(start, duration, path, 0L, true);
                } else {
                    FileReadEvent.commit(start, duration, path, bytesRead, false);
                }
            }
        }
        return bytesRead;
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

public final class JDKEvents {

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        // jdk.internal.event.* classes need their mirror
        // event class to be listed in the MirrorEvents class.
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ErrorThrownEvent.class,
        jdk.internal.event.ExceptionStatisticsEvent.class,
        jdk.internal.event.ExceptionThrownEvent.class,

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Field Type Description
path string Path Full path of the file, or N/A if a file descriptor was used to create the stream, for example System.in
bytesRead long: bytes Bytes Read Number of bytes read from the file (possibly 0)
endOfFile boolean End of File If end of file was reached

Examples 2
bytesRead long: bytes
27929
endOfFile boolean
false
path string
/home/runner/work/jfrevents/jfrevents/harness-004314-12543806468965242608/apache-spark/als/blockmgr-c9299705-d4b8-4005-b845-4a0cda9e6164/2d/shuffle_12_145_0.data
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
162
lineNumber int
113
method Method
descriptor string
([BII)I
hidden boolean
false
modifiers int
1
name string
read
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/FileInputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/io
type FrameType
Inlined
truncated boolean
true
startTime long: millis
383966275978
bytesRead long: bytes
30
endOfFile boolean
false
path string
/home/runner/work/jfrevents/jfrevents/harness-004327-18431318799373161124/apache-spark/lib/scala-reflect-2.13.12.jar
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
114
lineNumber int
114
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/RandomAccessFile
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
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name string
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type FrameType
Interpreted
truncated boolean
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startTime long: millis
454792446498

VirtualThreadPinned

profiling default startTime duration stackTrace 19 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/VirtualThreadPinnedEvent.java

Category: Java Application

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/VirtualThreadPinnedEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.MirrorEvent;

@Category("Java Application")
@Label("Virtual Thread Pinned")
@Name("jdk.VirtualThreadPinned")
@MirrorEvent(className = "jdk.internal.event.VirtualThreadPinnedEvent")
public final class VirtualThreadPinnedEvent extends AbstractJDKEvent {
}

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

public final class MirrorEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class,
        ErrorThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ExceptionThrownEvent.class,
    };

    private static final Map<String, Class<? extends Event>> mirrorLookup = createLookup();

    public static Class<? extends Event> find(String name) {

src/java.base/share/classes/jdk/internal/event/VirtualThreadPinnedEvent.java:

package jdk.internal.event;

/**
 * Event recording that a virtual thread has parked on its carrier thread.
 */
public class VirtualThreadPinnedEvent extends Event {
}

src/java.base/share/classes/java/lang/VirtualThread.java:

    /**
     * Parks the current carrier thread up to the given waiting time or until
     * unparked or interrupted. If the virtual thread is interrupted then the
     * interrupt status will be propagated to the carrier thread.
     * @param timed true for a timed park, false for untimed
     * @param nanos the waiting time in nanoseconds
     */
    private void parkOnCarrierThread(boolean timed, long nanos) {
        assert state() == RUNNING;

        VirtualThreadPinnedEvent event;
        try {
            event = new VirtualThreadPinnedEvent();
            event.begin();
        } catch (OutOfMemoryError e) {
            event = null;
        }

        setState(timed ? TIMED_PINNED : PINNED);
        try {
            if (!parkPermit) {
                if (!timed) {
                    U.park(false, 0);
                } else if (nanos > 0) {

Configuration enabled stackTrace threshold
profiling true true 20 ms
default true true 20 ms

FileWrite

profiling default startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/FileWriteEvent.java

Category: Java Application

Writing data to a file

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/FileWriteEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.DataAmount;
import jdk.jfr.Name;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "FileWrite")
@Label("File Write")
@Category("Java Application")
@Description("Writing data to a file")
public final class FileWriteEvent extends AbstractJDKEvent {

    // The order of these fields must be the same as the parameters in
    // commit(..., String, long)

    @Label("Path")
    @Description("Full path of the file, or N/A if a file descriptor was used to create the stream, for example System.out and System.err")
    public String path;

    @Label("Bytes Written")
    @Description("Number of bytes written to the file")
    @DataAmount

src/jdk.jfr/share/classes/jdk/jfr/events/EventConfigurations.java:

package jdk.jfr.events;
import jdk.jfr.internal.JVMSupport;
import jdk.jfr.internal.event.EventConfiguration;

public final class EventConfigurations {
    public static final EventConfiguration FILE_READ = JVMSupport.getConfiguration(FileReadEvent.class);
    public static final EventConfiguration FILE_WRITE = JVMSupport.getConfiguration(FileWriteEvent.class);
    public static final EventConfiguration FILE_FORCE = JVMSupport.getConfiguration(FileForceEvent.class);
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/RandomAccessFileInstrumentor.java:

        if (!eventConfiguration.isEnabled()) {
            write(b);
            return;
        }
        long bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            write(b);
            bytesWritten = 1;
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileWriteEvent.commit(start, duration, path, bytesWritten);
            }
        }
    }

    @JIInstrumentationMethod
    public void write(byte b[]) throws IOException {
        EventConfiguration eventConfiguration = EventConfigurations.FILE_WRITE;
        if (!eventConfiguration.isEnabled()) {
            write(b);
            return;
        }
        long bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            write(b);
            bytesWritten = b.length;
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileWriteEvent.commit(start, duration, path, bytesWritten);
            }
        }
    }

    @JIInstrumentationMethod
    public void write(byte b[], int off, int len) throws IOException {
        EventConfiguration eventConfiguration = EventConfigurations.FILE_WRITE;
        if (!eventConfiguration.isEnabled()) {
            write(b, off, len);
            return;
        }
        long bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            write(b, off, len);
            bytesWritten = len;
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileWriteEvent.commit(start, duration, path, bytesWritten);
            }
        }
    }
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileChannelImplInstrumentor.java:

        EventConfiguration eventConfiguration = EventConfigurations.FILE_WRITE;
        if (!eventConfiguration.isEnabled()) {
            return write(src);
        }
        int bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            bytesWritten = write(src);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                long bytes = bytesWritten > 0 ? bytesWritten : 0;
                FileWriteEvent.commit(start, duration, path, bytes);
            }
        }
        return bytesWritten;
    }

    @JIInstrumentationMethod
    public int write(ByteBuffer src, long position) throws IOException {
        EventConfiguration eventConfiguration = EventConfigurations.FILE_WRITE;
        if (!eventConfiguration.isEnabled()) {
            return write(src, position);
        }

        int bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            bytesWritten = write(src, position);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                long bytes = bytesWritten > 0 ? bytesWritten : 0;
                FileWriteEvent.commit(start, duration, path, bytes);
            }
        }
        return bytesWritten;
    }

    @JIInstrumentationMethod
    public long write(ByteBuffer[] srcs, int offset, int length) throws IOException {
        EventConfiguration eventConfiguration = EventConfigurations.FILE_WRITE;
        if (!eventConfiguration.isEnabled()) {
            return write(srcs, offset, length);
        }
        long bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            bytesWritten = write(srcs, offset, length);
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                long bytes = bytesWritten > 0 ? bytesWritten : 0;
                FileWriteEvent.commit(start, duration, path, bytes);
            }
        }
        return bytesWritten;
    }
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/FileOutputStreamInstrumentor.java:

        if (!eventConfiguration.isEnabled()) {
            write(b);
            return;
        }
        long bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            write(b);
            bytesWritten = 1;
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileWriteEvent.commit(start, duration, path, bytesWritten);
            }
        }
    }

    @JIInstrumentationMethod
    public void write(byte b[]) throws IOException {
        EventConfiguration eventConfiguration = EventConfigurations.FILE_WRITE;
        if (!eventConfiguration.isEnabled()) {
            write(b);
            return;
        }
        long bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            write(b);
            bytesWritten = b.length;
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileWriteEvent.commit(start, duration, path, bytesWritten);
            }
        }
    }

    @JIInstrumentationMethod
    public void write(byte b[], int off, int len) throws IOException {
        EventConfiguration eventConfiguration = EventConfigurations.FILE_WRITE;
        if (!eventConfiguration.isEnabled()) {
            write(b, off, len);
            return;
        }
        long bytesWritten = 0;
        long start = 0;
        try {
            start = EventConfiguration.timestamp();
            write(b, off, len);
            bytesWritten = len;
        } finally {
            long duration = EventConfiguration.timestamp() - start;
            if (eventConfiguration.shouldCommit(duration)) {
                FileWriteEvent.commit(start, duration, path, bytesWritten);
            }
        }
    }
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

public final class JDKEvents {

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        // jdk.internal.event.* classes need their mirror
        // event class to be listed in the MirrorEvents class.
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ErrorThrownEvent.class,
        jdk.internal.event.ExceptionStatisticsEvent.class,
        jdk.internal.event.ExceptionThrownEvent.class,
        jdk.internal.event.ProcessStartEvent.class,

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Field Type Description
path string Path Full path of the file, or N/A if a file descriptor was used to create the stream, for example System.out and System.err
bytesWritten long: bytes Bytes Written Number of bytes written to the file

SocketWrite

profiling default startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/SocketWriteEvent.java

Category: Java Application

Writing data to a socket

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/SocketWriteEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "SocketWrite")
@Label("Socket Write")
@Category("Java Application")
@Description("Writing data to a socket")
@MirrorEvent(className = "jdk.internal.event.SocketWriteEvent")
public final class SocketWriteEvent extends AbstractJDKEvent {

    @Label("Remote Host")
    public String host;

    @Label("Remote Address")
    public String address;

    @Label("Remote Port")
    public int port;

    @Label("Bytes Written")

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

public final class MirrorEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class,
        ErrorThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ExceptionThrownEvent.class,

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

public final class JDKEvents {

    private static final Class<?>[] eventClasses = {
        FileForceEvent.class,
        FileReadEvent.class,
        FileWriteEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ActiveSettingEvent.class,
        ActiveRecordingEvent.class,
        // jdk.internal.event.* classes need their mirror
        // event class to be listed in the MirrorEvents class.
        jdk.internal.event.DeserializationEvent.class,
        jdk.internal.event.ErrorThrownEvent.class,
        jdk.internal.event.ExceptionStatisticsEvent.class,
        jdk.internal.event.ExceptionThrownEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.SecurityProviderServiceEvent.class,

src/java.base/share/classes/sun/nio/ch/SocketChannelImpl.java:

            writeLock.unlock();
        }
    }

    @Override
    public int write(ByteBuffer buf) throws IOException {
        if (!SocketWriteEvent.enabled()) {
            return implWrite(buf);
        }
        long start = SocketWriteEvent.timestamp();
        int nbytes = implWrite(buf);
        SocketWriteEvent.offer(start, nbytes, remoteAddress());
        return nbytes;
    }

    @Override
    public long write(ByteBuffer[] srcs, int offset, int length)
        throws IOException
    {
        if (!SocketWriteEvent.enabled()) {
            return implWrite(srcs, offset, length);
        }
        long start = SocketWriteEvent.timestamp();
        long nbytes = implWrite(srcs, offset, length);
        SocketWriteEvent.offer(start, nbytes, remoteAddress());
        return nbytes;
    }

    /**

src/java.base/share/classes/sun/nio/ch/SocketOutputStream.java:

    SocketChannelImpl channel() {
        return sc;
    }

    @Override
    public void write(int b) throws IOException {
        byte[] a = new byte[]{(byte) b};
        write(a, 0, 1);
    }

    @Override
    public void write(byte[] b, int off, int len) throws IOException {
        if (!SocketWriteEvent.enabled()) {
            sc.blockingWriteFully(b, off, len);
            return;
        }
        long start = SocketWriteEvent.timestamp();
        sc.blockingWriteFully(b, off, len);
        SocketWriteEvent.offer(start, len, sc.remoteAddress());
    }

    @Override
    public void close() throws IOException {
        sc.close();
    }
}

src/java.base/share/classes/jdk/internal/event/SocketWriteEvent.java:

/**
 * A JFR event for socket write operations.  This event is mirrored in
 * {@code jdk.jfr.events.SocketWriteEvent } where the metadata for the event is
 * provided with annotations.  Some of the methods are replaced by generated
 * methods when jfr is enabled.  Note that the order of the arguments of the
 * {@link #commit(long, long, String, String, int, long)} method
 * must be the same as the order of the fields.
 */
public class SocketWriteEvent extends Event {

    // THE ORDER OF THE FOLLOWING FIELDS IS IMPORTANT!
    // The order must match the argument order of the generated commit method.
    public String host;
    public String address;
    public int port;
    public long bytesWritten;

    /**
     * Actually commit a socket write event.  This is generated automatically.
     * The order of the fields must be the same as the parameters in this method.

src/java.base/share/classes/java/net/Socket.java:

        @Override
        public void write(int b) throws IOException {
            byte[] a = new byte[] { (byte) b };
            write(a, 0, 1);
        }
        @Override
        public void write(byte[] b, int off, int len) throws IOException {
            if (!SocketWriteEvent.enabled()) {
                implWrite(b, off, len);
                return;
            }
            long start = SocketWriteEvent.timestamp();
            implWrite(b, off, len);
            long duration = SocketWriteEvent.timestamp() - start;
            if (SocketWriteEvent.shouldCommit(duration)) {
                SocketWriteEvent.emit(start, duration, len, parent.getRemoteSocketAddress());
            }
        }

        private void implWrite(byte[] b, int off, int len) throws IOException {
            try {
                out.write(b, off, len);

Configuration enabled stackTrace threshold
profiling true true 10 ms
default true true 20 ms

Field Type Description
host string Remote Host
address string Remote Address
port int Remote Port
bytesWritten long: bytes Bytes Written Number of bytes written to the socket

JavaExceptionThrow

startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ExceptionThrownEvent.java

Category: Java Application

An object derived from java.lang.Exception has been created

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
message string Message
thrownClass Class Class

Examples 3
message string
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
30
lineNumber int
259
method Method
descriptor string
()V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Throwable
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Inlined
truncated boolean
true
startTime long: millis
351734249679
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/EOFException
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/io
message string
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
62
lineNumber int
375
method Method
descriptor string
(Ljava/lang/String;Ljava/lang/Throwable;ZZ)V
hidden boolean
false
modifiers int
4
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Throwable
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
298894876158
thrownClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
scala/runtime/NonLocalReturnControl
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/runtime
message string
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
30
lineNumber int
259
method Method
descriptor string
()V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Throwable
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Inlined
truncated boolean
true
startTime long: millis
398427696527
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/EOFException
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/io

Java Application Statistics

JavaThreadStatistics

profiling default startTime duration every chunk 11 17 21 25 26 27 graal vm

Category: Java Application / Statistics

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

 *
 *  If running inside a guest OS on top of a hypervisor in a virtualized environment,
 *  the total memory reported is the amount of memory configured for the guest OS by the hypervisor.
 */
TRACE_REQUEST_FUNC(PhysicalMemory) {
  u8 totalPhysicalMemory = os::physical_memory();
  EventPhysicalMemory event;
  event.set_totalSize(totalPhysicalMemory);
  event.set_usedSize(totalPhysicalMemory - os::available_memory());
  event.commit();
}

TRACE_REQUEST_FUNC(JavaThreadStatistics) {
  EventJavaThreadStatistics event;
  event.set_activeCount(ThreadService::get_live_thread_count());
  event.set_daemonCount(ThreadService::get_daemon_thread_count());
  event.set_accumulatedCount(ThreadService::get_total_thread_count());
  event.set_peakCount(ThreadService::get_peak_thread_count());
  event.commit();
}

TRACE_REQUEST_FUNC(GCHeapMemoryUsage) {
  MemoryUsage usage = Universe::heap()->memory_usage();
  EventGCHeapMemoryUsage event(UNTIMED);
  event.set_used(usage.used());

Configuration enabled period
profiling true 1000 ms
default true 1000 ms

Field Type Description
activeCount long Active Threads Number of live active threads including both daemon and non-daemon threads
daemonCount long Daemon Threads Number of live daemon threads
accumulatedCount long Accumulated Threads Number of threads created and also started since JVM start
peakCount long Peak Threads Peak live thread count since JVM start or when peak count was reset

Examples 3
accumulatedCount long
1827
activeCount long
73
daemonCount long
68
peakCount long
272
startTime long: millis
382002993590
accumulatedCount long
1708
activeCount long
95
daemonCount long
94
peakCount long
293
startTime long: millis
479440093576
accumulatedCount long
1651
activeCount long
63
daemonCount long
62
peakCount long
275
startTime long: millis
438207180759

ClassLoadingStatistics

profiling default startTime duration every chunk 11 17 21 25 26 27 graal vm

Category: Java Application / Statistics

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

      event.set_used(usage.used());
      event.set_committed(usage.committed());
      event.set_max(usage.max_size());
      event.set_starttime(timestamp());
      event.set_endtime(timestamp());
      event.commit();
    }
  }
}


TRACE_REQUEST_FUNC(ClassLoadingStatistics) {
#if INCLUDE_MANAGEMENT
  EventClassLoadingStatistics event;
  event.set_loadedClassCount(ClassLoadingService::loaded_class_count());
  event.set_unloadedClassCount(ClassLoadingService::unloaded_class_count());
  event.commit();
#else
  log_debug(jfr, system)("Unable to generate requestable event ClassLoadingStatistics. The required jvm feature 'management' is missing.");
#endif
}

class JfrClassLoaderStatsClosure : public ClassLoaderStatsClosure {
public:
  JfrClassLoaderStatsClosure() : ClassLoaderStatsClosure(nullptr) {}

Configuration enabled period
profiling true 1000 ms
default true 1000 ms

Field Type Description
loadedClassCount long Loaded Class Count Number of classes loaded since JVM start
unloadedClassCount long Unloaded Class Count Number of classes unloaded since JVM start

Examples 3
loadedClassCount long
96604
startTime long: millis
422657113456
unloadedClassCount long
2329
loadedClassCount long
96726
startTime long: millis
459553111096
unloadedClassCount long
2384
loadedClassCount long
94939
startTime long: millis
326990291639
unloadedClassCount long
3761

ClassLoaderStatistics

profiling default startTime duration every chunk 11 17 21 25 26 27

Category: Java Application / Statistics

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  log_debug(jfr, system)("Unable to generate requestable event ClassLoadingStatistics. The required jvm feature 'management' is missing.");
#endif
}

class JfrClassLoaderStatsClosure : public ClassLoaderStatsClosure {
public:
  JfrClassLoaderStatsClosure() : ClassLoaderStatsClosure(nullptr) {}

  bool do_entry(oop const& key, ClassLoaderStats const& cls) {
    const ClassLoaderData* this_cld = cls._class_loader != nullptr ?
      java_lang_ClassLoader::loader_data_acquire(cls._class_loader) : nullptr;
    const ClassLoaderData* parent_cld = cls._parent != nullptr ?
      java_lang_ClassLoader::loader_data_acquire(cls._parent) : nullptr;
    EventClassLoaderStatistics event;
    event.set_classLoader(this_cld);
    event.set_parentClassLoader(parent_cld);
    event.set_classLoaderData((intptr_t)cls._cld);
    event.set_classCount(cls._classes_count);
    event.set_chunkSize(cls._chunk_sz);
    event.set_blockSize(cls._block_sz);
    event.set_hiddenClassCount(cls._hidden_classes_count);
    event.set_hiddenChunkSize(cls._hidden_chunk_sz);
    event.set_hiddenBlockSize(cls._hidden_block_sz);
    event.commit();
    return true;

Configuration enabled period
profiling true everyChunk
default true everyChunk

Field Type Description
classLoader ClassLoader Class Loader
parentClassLoader ClassLoader Parent Class Loader
classLoaderData ulong: address ClassLoaderData Pointer Pointer to the ClassLoaderData structure in the JVM
classCount long Classes Number of loaded classes
chunkSize ulong: bytes Total Chunk Size Total size of all allocated metaspace chunks (each chunk has several blocks)
blockSize ulong: bytes Total Block Size Total size of all allocated metaspace blocks (each chunk has several blocks)
hiddenClassCount long 15+ Hidden Classes Number of hidden classes
hiddenChunkSize ulong: bytes 15+ Total Hidden Classes Chunk Size Total size of all allocated metaspace chunks for hidden classes (each chunk has several blocks)
hiddenBlockSize ulong: bytes 15+ Total Hidden Classes Block Size Total size of all allocated metaspace blocks for hidden classes (each chunk has several blocks)

Examples 3
blockSize ulong: bytes
3440
chunkSize ulong: bytes
4096
classCount long
1
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
jdk/internal/reflect/DelegatingClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
jdk/internal/reflect
classLoaderData ulong: address
140527037843408
hiddenBlockSize ulong: bytes
0
hiddenChunkSize ulong: bytes
0
hiddenClassCount long
0
parentClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
startTime long: millis
296999388369
blockSize ulong: bytes
3176
chunkSize ulong: bytes
4096
classCount long
1
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
jdk/internal/reflect/DelegatingClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
jdk/internal/reflect
classLoaderData ulong: address
140564663628768
hiddenBlockSize ulong: bytes
0
hiddenChunkSize ulong: bytes
0
hiddenClassCount long
0
parentClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
startTime long: millis
351492185534
blockSize ulong: bytes
3488
chunkSize ulong: bytes
4096
classCount long
1
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
jdk/internal/reflect/DelegatingClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
jdk/internal/reflect
classLoaderData ulong: address
140324100899376
hiddenBlockSize ulong: bytes
0
hiddenChunkSize ulong: bytes
0
hiddenClassCount long
0
parentClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
startTime long: millis
398060276529

ThreadAllocationStatistics

profiling default startTime every chunk 11 17 21 25 26 27 graal vm

Category: Java Application / Statistics

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  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 != nullptr, "invariant");
    allocated.append(jt->cooked_allocated_bytes());
    thread_ids.append(JFR_JVM_THREAD_ID(jt));
  }

  // Write allocation statistics to buffer.
  for(int i = 0; i < thread_ids.length(); i++) {
    EventThreadAllocationStatistics event(UNTIMED);
    event.set_allocated(allocated.at(i));
    event.set_thread(thread_ids.at(i));
    event.set_starttime(time_stamp);
    event.set_endtime(time_stamp);
    event.commit();
  }
}

/**
 *  PhysicalMemory event represents:
 *

Configuration enabled period
profiling true everyChunk
default true everyChunk

Field Type Description
allocated ulong: bytes Allocated Approximate number of bytes allocated since thread start
thread Thread Thread

Examples 3
allocated ulong: bytes
227334136
startTime long: millis
297002594661
thread Thread
group ThreadGroup
name string
finagle/netty4
parent ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
finagle/netty4-2-5
javaThreadId long
855
osName string
finagle/netty4-2-5
osThreadId long
3404
virtual boolean
false
allocated ulong: bytes
80
startTime long: millis
351492405286
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
QueryStageCreator-2
javaThreadId long
977
osName string
QueryStageCreator-2
osThreadId long
3594
virtual boolean
false
allocated ulong: bytes
7162768
startTime long: millis
398060452027
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
RxComputationThreadPool-2
javaThreadId long
830
osName string
RxComputationThreadPool-2
osThreadId long
3375
virtual boolean
false

FinalizerStatistics

profiling default startTime end of every chunk 18 21 25 26 27

Category: Java Application / Statistics

Per class statistics about finalizers

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrFinalizerStatisticsEvent.cpp:

static void send_event(const FinalizerEntry* fe, const InstanceKlass* ik, const JfrTicks& timestamp, Thread* thread) {
  assert(ik != nullptr, "invariant");
  assert(ik->has_finalizer(), "invariant");
  assert(thread != nullptr, "invariant");
  const char* const url = fe != nullptr ? fe->codesource() : nullptr;
  const traceid url_symbol_id = url != nullptr ? JfrSymbolTable::add(url) : 0;
  EventFinalizerStatistics event(UNTIMED);
  event.set_starttime(timestamp);
  event.set_endtime(timestamp);
  event.set_finalizableClass(ik);
  event.set_codeSource(url_symbol_id);
  if (fe == nullptr) {
    event.set_objects(0);
    event.set_totalFinalizersRun(0);
  } else {
    assert(fe->klass() == ik, "invariant");
    event.set_objects(fe->objects_on_heap());
    event.set_totalFinalizersRun(fe->total_finalizers_run());
  }
  event.commit();
}

void JfrFinalizerStatisticsEvent::send_unload_event(const InstanceKlass* ik) {
  if (!EventFinalizerStatistics::is_enabled()) {
    return;
  }
  Thread* const thread = Thread::current();
  ResourceMark rm(thread);
  send_event(FinalizerService::lookup(ik, thread), ik, JfrTicks::now(), thread);
}

// Finalizer events generated by the periodic task will all have the same timestamp.

class FinalizerStatisticsEventClosure : public FinalizerEntryClosure {
 private:

Configuration enabled period
profiling true endChunk
default true endChunk

Field Type Description
finalizableClass Class Class Overriding Finalize
codeSource Symbol Code Source URL from where the class was loaded
objects ulong Finalizable Objects on Heap Number of objects on heap that can be finalized
totalFinalizersRun ulong Finalizers Run Total number of finalizers run since JVM start

Examples 3
codeSource Symbol
file:///home/runner/work/jfrevents/jfrevents/harness-004327-18431318799373161124/apache-spark/lib/netty-buffer-4.1.99.Final.jar
finalizableClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
24
name string
io/netty/buffer/PoolArena$DirectArena
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/buffer
objects ulong
16
startTime long: millis
405682763163
totalFinalizersRun ulong
0
codeSource Symbol
file:///home/runner/work/jfrevents/jfrevents/harness-004314-16904521565326391942/apache-spark/lib/netty-buffer-4.1.99.Final.jar
finalizableClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
24
name string
io/netty/buffer/PoolArena$HeapArena
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/buffer
objects ulong
16
startTime long: millis
370338674447
totalFinalizersRun ulong
0
codeSource Symbol
file:///home/runner/work/jfrevents/jfrevents/harness-004314-6346519699961129921/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
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
24
name string
io/netty/buffer/PoolArena$HeapArena
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/buffer
objects ulong
8
startTime long: millis
306964676866
totalFinalizersRun ulong
0

DeprecatedInvocation

profiling default startTime stackTrace 22 25 26 27

Category: Java Application / Statistics

A unique invocation of a method that is annotated with @Deprecated. Packages and modules that are deprecated are ignored. At most 10 000 invocation sites and only the first invocation from a class is guaranteed to be included.

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/jni/jfrJniMethod.cpp:

NO_TRANSITION(jdouble, jfr_time_conv_factor(JNIEnv* env, jclass jvm))
  return (jdouble)JfrTimeConverter::nano_to_counter_multiplier();
NO_TRANSITION_END

NO_TRANSITION(jboolean, jfr_set_throttle(JNIEnv* env, jclass jvm, jlong event_type_id, jlong event_sample_size, jlong period_ms))
  JfrEventThrottler::configure(static_cast<JfrEventId>(event_type_id), event_sample_size, period_ms);
  return JNI_TRUE;
NO_TRANSITION_END

NO_TRANSITION(void, jfr_set_miscellaneous(JNIEnv* env, jobject jvm, jlong event_type_id, jlong value))
  JfrEventSetting::set_miscellaneous(event_type_id, value);
  const JfrEventId typed_event_id = (JfrEventId)event_type_id;
  if (EventDeprecatedInvocation::eventId == typed_event_id) {
    JfrDeprecationManager::on_level_setting_update(value);
  }
NO_TRANSITION_END

NO_TRANSITION(jboolean, jfr_should_rotate_disk(JNIEnv* env, jclass jvm))
  return JfrChunkRotation::should_rotate() ? JNI_TRUE : JNI_FALSE;
NO_TRANSITION_END

NO_TRANSITION(jlong, jfr_get_type_id_from_string(JNIEnv * env, jclass jvm, jstring type))
  const char* type_name = env->GetStringUTFChars(type, nullptr);
  jlong id = JfrType::name_to_id(type_name);

Configuration enabled level stackTrace
profiling true forRemoval true
default true forRemoval true

Field Type Description
method Method Deprecated Method
invocationTime Ticks Invocation Time The time the deprecated method was invoked for the first time
forRemoval boolean For Removal

ExceptionStatistics

profiling default startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ExceptionStatisticsEvent.java

Category: Java Application / Statistics

Number of objects derived from java.lang.Throwable that have been created

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/ExceptionStatisticsEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.StackTrace;
import jdk.jfr.internal.MirrorEvent;
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")
@MirrorEvent(className = "jdk.internal.event.ExceptionStatisticsEvent")
@StackTrace(false)
public final class ExceptionStatisticsEvent extends AbstractPeriodicEvent {

    @Label("Exceptions Created")
    public long throwables;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class,
        ErrorThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ExceptionThrownEvent.class,
    };

    private static final Map<String, Class<? extends Event>> mirrorLookup = createLookup();

    public static Class<? extends Event> find(String name) {
        // When <clinit> of this class is executed it may lead
        // to a JVM up call and invocation of this method before
        // the mirrorLookup field has been set. This is fine,
        // mirrors should not be instrumented.
        if (mirrorLookup != null) {

src/java.base/share/classes/jdk/internal/event/ThrowableTracer.java:

        if (ErrorThrownEvent.enabled()) {
            long timestamp = ErrorThrownEvent.timestamp();
            ErrorThrownEvent.commit(timestamp, message, clazz);
        }
        if (ExceptionThrownEvent.enabled()) {
            long timestamp = ExceptionThrownEvent.timestamp();
            ExceptionThrownEvent.commit(timestamp, message, clazz);
        }
        numThrowables.incrementAndGet();
    }

    public static void traceThrowable(Class<?> clazz, String message) {
        if (ExceptionThrownEvent.enabled()) {
            long timestamp = ExceptionThrownEvent.timestamp();
            ExceptionThrownEvent.commit(timestamp, message, clazz);
        }
        numThrowables.incrementAndGet();
    }

    public static void emitStatistics() {
        long timestamp = ExceptionStatisticsEvent.timestamp();
        ExceptionStatisticsEvent.commit(timestamp, numThrowables.get());
    }
}

src/java.base/share/classes/jdk/internal/event/ExceptionStatisticsEvent.java:

package jdk.internal.event;

/**
 * Event recording number of exceptions that has been created.
 */
public class ExceptionStatisticsEvent extends Event {

    public long throwables;

    public static void commit(long timestamp, long throwables) {
        // Generated by JFR
    }

    public static boolean enabled() {
        // Generated by JFR
        return false;
    }

    public static long timestamp() {
        // Generated by JFR
        return 0;
    }
}

Configuration enabled period
profiling true 1000 ms
default true 1000 ms

Field Type Description
throwables long Exceptions Created

Examples 3
stackTrace StackTrace
null
startTime long: millis
440239385023
throwables long
2227632
stackTrace StackTrace
null
startTime long: millis
334601545816
throwables long
2202928
stackTrace StackTrace
null
startTime long: millis
475163915683
throwables long
2224940

DirectBufferStatistics

profiling default startTime duration stackTrace 15 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/DirectBufferStatisticsEvent.java

Category: Java Application / Statistics

Statistics of direct buffer

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/DirectBufferStatisticsEvent.java:

package jdk.jfr.events;

import jdk.internal.misc.VM;
import jdk.internal.misc.VM.BufferPool;

import jdk.jfr.*;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "DirectBufferStatistics")
@Label("Direct Buffer Statistics")
@Description("Statistics of direct buffer")
public final class DirectBufferStatisticsEvent extends AbstractBufferStatisticsEvent {

    private static final BufferPool DIRECT_BUFFER_POOL = findPoolByName("direct");

    public DirectBufferStatisticsEvent() {
        super(DIRECT_BUFFER_POOL);
        this.maxCapacity = VM.maxDirectMemory();
    }

    @Label("Maximum Capacity")
    @Description("Maximum direct buffer capacity the process can use")
    @DataAmount
    final long maxCapacity;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.SecurityProviderServiceEvent.class,
        jdk.internal.event.SocketReadEvent.class,
        jdk.internal.event.SocketWriteEvent.class,
        jdk.internal.event.ThreadSleepEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.VirtualThreadStartEvent.class,
        jdk.internal.event.VirtualThreadEndEvent.class,
        jdk.internal.event.VirtualThreadPinnedEvent.class,
        jdk.internal.event.VirtualThreadSubmitFailedEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,
        DirectBufferStatisticsEvent.class,
        InitialSecurityPropertyEvent.class,
    };

    // This is a list of the classes with instrumentation code that should be applied.
    private static final Class<?>[] instrumentationClasses = new Class<?>[] {
        FileInputStreamInstrumentor.class,
        FileOutputStreamInstrumentor.class,
        RandomAccessFileInstrumentor.class,
        FileChannelImplInstrumentor.class
    };

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

    private static final Runnable emitContainerIOUsage = JDKEvents::emitContainerIOUsage;
    private static final Runnable emitInitialSecurityProperties = JDKEvents::emitInitialSecurityProperties;
    private static Metrics containerMetrics = null;
    private static boolean initializationTriggered;

    @SuppressWarnings("unchecked")
    public static synchronized void initialize() {
        try {
            if (initializationTriggered == false) {
                for (Class<?> eventClass : eventClasses) {
                    SecuritySupport.registerEvent((Class<? extends Event>) eventClass);
                }
                PeriodicEvents.addJDKEvent(jdk.internal.event.ExceptionStatisticsEvent.class, emitExceptionStatistics);
                PeriodicEvents.addJDKEvent(DirectBufferStatisticsEvent.class, emitDirectBufferStatistics);
                PeriodicEvents.addJDKEvent(InitialSecurityPropertyEvent.class, emitInitialSecurityProperties);

                initializeContainerEvents();
                ThrowableTracer.enable();
                initializationTriggered = true;
            }
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not initialize JDK events. " + e.getMessage());
        }
    }

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

    public static void remove() {
        PeriodicEvents.removeEvent(emitExceptionStatistics);
        PeriodicEvents.removeEvent(emitDirectBufferStatistics);
        PeriodicEvents.removeEvent(emitInitialSecurityProperties);

        PeriodicEvents.removeEvent(emitContainerConfiguration);
        PeriodicEvents.removeEvent(emitContainerCPUUsage);
        PeriodicEvents.removeEvent(emitContainerCPUThrottling);
        PeriodicEvents.removeEvent(emitContainerMemoryUsage);
        PeriodicEvents.removeEvent(emitContainerIOUsage);
    }

    private static void emitDirectBufferStatistics() {
        DirectBufferStatisticsEvent e = new DirectBufferStatisticsEvent();
        e.commit();
    }

    private static void emitInitialSecurityProperties() {
        Properties p = SharedSecrets.getJavaSecurityPropertiesAccess().getInitialProperties();
        if (p != null) {
            for (String key : p.stringPropertyNames()) {
                InitialSecurityPropertyEvent e = new InitialSecurityPropertyEvent();
                e.key = key;
                e.value = p.getProperty(key);
                e.commit();

Configuration enabled period
profiling true 5 s
default true 5 s

Examples 3
stackTrace StackTrace
null
startTime long: millis
505182980720
stackTrace StackTrace
null
startTime long: millis
467307465461
stackTrace StackTrace
null
startTime long: millis
335725319654

Java Development Kit

VirtualThreadSubmitFailed

profiling default startTime duration stackTrace 19 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/VirtualThreadSubmitFailedEvent.java

Category: Java Development Kit / Threading

Submit of task for virtual thread failed

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/VirtualThreadSubmitFailedEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.MirrorEvent;
import jdk.jfr.internal.RemoveFields;

@Category({"Java Development Kit", "Threading"})
@Label("Virtual Thread Submit Failed")
@Name("jdk.VirtualThreadSubmitFailed")
@Description("Submit of task for virtual thread failed")
@MirrorEvent(className = "jdk.internal.event.VirtualThreadSubmitFailedEvent")
@RemoveFields("duration")
public final class VirtualThreadSubmitFailedEvent extends AbstractJDKEvent {

    @Label("Thread Id")
    public long javaThreadId;

    @Label("Exception Message")
    public String exceptionMessage;

}

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

public final class MirrorEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class,
        ErrorThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ExceptionThrownEvent.class,
    };

    private static final Map<String, Class<? extends Event>> mirrorLookup = createLookup();

    public static Class<? extends Event> find(String name) {
        // When <clinit> of this class is executed it may lead

src/java.base/share/classes/jdk/internal/event/VirtualThreadSubmitFailedEvent.java:

package jdk.internal.event;

/**
 * Event recording when an attempt to submit the task for a virtual thread failed.
 */
public class VirtualThreadSubmitFailedEvent extends Event {
    public long javaThreadId;
    public String exceptionMessage;
}

src/java.base/share/classes/java/lang/VirtualThread.java:

     * @throws RejectedExecutionException
     * @see ForkJoinPool#externalSubmit(ForkJoinTask)
     */
    private void externalSubmitRunContinuation(ForkJoinPool pool) {
        try {
            pool.externalSubmit(ForkJoinTask.adapt(runContinuation));
        } catch (RejectedExecutionException ree) {
            submitFailed(ree);
            throw ree;
        }
    }

    /**
     * If enabled, emits a JFR VirtualThreadSubmitFailedEvent.
     */
    private void submitFailed(RejectedExecutionException ree) {
        var event = new VirtualThreadSubmitFailedEvent();
        if (event.isEnabled()) {
            event.javaThreadId = threadId();
            event.exceptionMessage = ree.getMessage();
            event.commit();
        }
    }

    /**
     * Runs a task in the context of this virtual thread.
     */
    private void run(Runnable task) {

Configuration enabled stackTrace
profiling true true
default true true

Field Type Description
javaThreadId long Thread Id
exceptionMessage string Exception Message

X509Validation

startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/X509ValidationEvent.java

Category: Java Development Kit / Security

Serial numbers from X.509 Certificates forming chain of trust

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/X509ValidationEvent.java:

package jdk.jfr.events;

import jdk.jfr.*;
import jdk.jfr.internal.MirrorEvent;
import jdk.jfr.internal.RemoveFields;

@Category({"Java Development Kit", "Security"})
@Label("X509 Validation")
@Name("jdk.X509Validation")
@Description("Serial numbers from X.509 Certificates forming chain of trust")
@MirrorEvent(className = "jdk.internal.event.X509ValidationEvent")
@RemoveFields("duration")
public final class X509ValidationEvent extends AbstractJDKEvent {
    @CertificateId
    @Label("Certificate Id")
    @Unsigned
    public long certificateId;

    @Label("Certificate Position")
    @Description("Certificate position in chain of trust, 1 = trust anchor")
    public int certificatePosition;

    @Label("Validation Counter")
    public long validationCounter;

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class,
        ErrorThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ExceptionThrownEvent.class,
    };

    private static final Map<String, Class<? extends Event>> mirrorLookup = createLookup();

    public static Class<? extends Event> find(String name) {
        // When <clinit> of this class is executed it may lead
        // to a JVM up call and invocation of this method before
        // the mirrorLookup field has been set. This is fine,

src/java.base/share/classes/jdk/internal/event/X509ValidationEvent.java:

package jdk.internal.event;

/**
 * Event recording details of X.509 Certificate serial numbers
 * used in X509 cert path validation.
 */

public final class X509ValidationEvent extends Event {
    public long certificateId;
    public int certificatePosition;
    public long validationCounter;
}

src/java.base/share/classes/sun/security/provider/certpath/PKIXCertPathValidator.java:

        // only add a RevocationChecker if revocation is enabled and
        // a PKIXRevocationChecker has not already been added
        if (params.revocationEnabled() && !revCheckerAdded) {
            certPathCheckers.add(new RevocationChecker(anchor, params));
        }
        // add user-specified checkers
        certPathCheckers.addAll(checkers);

        PKIXMasterCertPathValidator.validate(params.certPath(),
                                             params.certificates(),
                                             certPathCheckers);

        X509ValidationEvent xve = new X509ValidationEvent();
        if (xve.shouldCommit() || EventHelper.isLoggingSecurity()) {
            long[] certIds = params.certificates().stream()
                    .mapToInt(Certificate::hashCode)
                    .mapToLong(Integer::toUnsignedLong)
                    .toArray();
            int hash = (anchorCert != null) ?
                anchorCert.hashCode() : anchor.getCAPublicKey().hashCode();
            long anchorCertId = Integer.toUnsignedLong(hash);
            if (xve.shouldCommit()) {
                xve.certificateId = anchorCertId;
                int certificatePos = 1; // most trusted CA

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
certificateId ulong: certificateId Certificate Id
certificatePosition int Certificate Position Certificate position in chain of trust, 1 = trust anchor
validationCounter long Validation Counter

SecurityProviderService

startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/SecurityProviderServiceEvent.java

Category: Java Development Kit / Security

Excludes in stack trace: java.security.Provider::getService

Details of Provider.getInstance(String type, String algorithm) calls

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/SecurityProviderServiceEvent.java:

@Category({"Java Development Kit", "Security"})
@Label("Security Provider Instance Request")
@Name("jdk.SecurityProviderService")
@Description("Details of Provider.getInstance(String type, String algorithm) calls")
@MirrorEvent(className = "jdk.internal.event.SecurityProviderServiceEvent")
@RemoveFields("duration")
@StackFilter({"java.security.Provider::getService"})
public final class SecurityProviderServiceEvent extends AbstractJDKEvent {
    @Label("Type of Service")
    public String type;

    @Label("Algorithm Name")
    public String algorithm;

    @Label("Security Provider")
    public String provider;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

public final class MirrorEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class,
        ErrorThrownEvent.class,

src/java.base/share/classes/jdk/internal/event/SecurityProviderServiceEvent.java:

package jdk.internal.event;

/**
 * Event recording details of Provider.getService(String type, String algorithm) calls
 */

public final class SecurityProviderServiceEvent extends Event {
    private final static SecurityProviderServiceEvent EVENT = new SecurityProviderServiceEvent();

    /**
     * Returns {@code true} if event is enabled, {@code false} otherwise.
     */
    public static boolean isTurnedOn() {
        return EVENT.isEnabled();
    }

    public String type;
    public String algorithm;
    public String provider;
}

src/java.base/share/classes/java/security/Provider.java:

        if (!key.matches(type, algorithm)) {
            key = new ServiceKey(type, algorithm, false);
            previousKey = key;
        }

        Service s = serviceMap.get(key);
        if (s == null) {
            s = legacyMap.get(key);
            if (s != null && !s.isValid()) {
                legacyMap.remove(key, s);
            }
        }

        if (s != null && SecurityProviderServiceEvent.isTurnedOn()) {
            var e  = new SecurityProviderServiceEvent();
            e.provider = getName();
            e.type = type;
            e.algorithm = algorithm;
            e.commit();
        }

        return s;
    }

    // ServiceKey from previous getService() call
    // by re-using it if possible we avoid allocating a new object

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
type string Type of Service
algorithm string Algorithm Name
provider string Security Provider

Examples 3
algorithm string
SHA256withDSA
provider string
SUN
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
138
lineNumber int
1301
method Method
descriptor string
(Ljava/lang/String;Ljava/lang/String;)Ljava/security/Provider$Service;
hidden boolean
false
modifiers int
1
name string
getService
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/security/Provider
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/security
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
466570161923
type string
Signature
algorithm string
SHA-256
provider string
SUN
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
138
lineNumber int
1301
method Method
descriptor string
(Ljava/lang/String;Ljava/lang/String;)Ljava/security/Provider$Service;
hidden boolean
false
modifiers int
1
name string
getService
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/security/Provider
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/security
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
345131866743
type string
MessageDigest
algorithm string
SHA
provider string
SUN
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
138
lineNumber int
1301
method Method
descriptor string
(Ljava/lang/String;Ljava/lang/String;)Ljava/security/Provider$Service;
hidden boolean
false
modifiers int
1
name string
getService
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/security/Provider
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/security
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
430658634398
type string
MessageDigest

Deserialization

startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/DeserializationEvent.java

Category: Java Development Kit / Serialization

Results of deserialization and ObjectInputFilter checks

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/DeserializationEvent.java:

@Category({"Java Development Kit", "Serialization"})
@Label("Deserialization")
@Name("jdk.Deserialization")
@Description("Results of deserialization and ObjectInputFilter checks")
@MirrorEvent(className = "jdk.internal.event.DeserializationEvent")
@RemoveFields("duration")
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/MirrorEvents.java:

public final class MirrorEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,

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();

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
filterConfigured boolean Filter Configured
filterStatus string Filter Status
type Class Type
arrayLength int Array Length
objectReferences long Object References
depth long Depth
bytesRead long Bytes Read
exceptionType Class Exception Type
exceptionMessage string Exception Message

Examples 3
arrayLength int
10
bytesRead long
26103
depth long
3
exceptionMessage string
null
exceptionType Class
null
filterConfigured boolean
false
filterStatus string
null
objectReferences long
528
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
304
lineNumber int
1436
method Method
descriptor string
(Ljava/lang/Class;I)V
hidden boolean
false
modifiers int
2
name string
filterCheck
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/ObjectInputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/io
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
295202057674
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[F
package Package
null
arrayLength int
10
bytesRead long
72148
depth long
3
exceptionMessage string
null
exceptionType Class
null
filterConfigured boolean
false
filterStatus string
null
objectReferences long
1449
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
304
lineNumber int
1436
method Method
descriptor string
(Ljava/lang/Class;I)V
hidden boolean
false
modifiers int
2
name string
filterCheck
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/ObjectInputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/io
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
349228795905
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[F
package Package
null
arrayLength int
-1
bytesRead long
884
depth long
2
exceptionMessage string
null
exceptionType Class
null
filterConfigured boolean
false
filterStatus string
null
objectReferences long
28
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
304
lineNumber int
1436
method Method
descriptor string
(Ljava/lang/Class;I)V
hidden boolean
false
modifiers int
2
name string
filterCheck
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/ObjectInputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/io
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
391569505087
type Class
null

X509Certificate

startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/X509CertificateEvent.java

Category: Java Development Kit / Security

Details of X.509 Certificate parsed by JDK

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/X509CertificateEvent.java:

package jdk.jfr.events;

import jdk.jfr.*;
import jdk.jfr.internal.MirrorEvent;
import jdk.jfr.internal.RemoveFields;

@Category({"Java Development Kit", "Security"})
@Label("X509 Certificate")
@Name("jdk.X509Certificate")
@Description("Details of X.509 Certificate parsed by JDK")
@MirrorEvent(className = "jdk.internal.event.X509CertificateEvent")
@RemoveFields("duration")
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;

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class,
        ErrorThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ExceptionThrownEvent.class,
    };

    private static final Map<String, Class<? extends Event>> mirrorLookup = createLookup();

    public static Class<? extends Event> find(String name) {
        // When <clinit> of this class is executed it may lead
        // to a JVM up call and invocation of this method before

src/java.base/share/classes/jdk/internal/event/X509CertificateEvent.java:

package jdk.internal.event;


/**
 * Event recording details of X.509 Certificate.
 */

public final class X509CertificateEvent extends Event {
    private static final X509CertificateEvent EVENT = new X509CertificateEvent();

    /**
     * Returns {@code true} if event is enabled, {@code false} otherwise.
     */
    public static boolean isTurnedOn() {
        return EVENT.isEnabled();
    }

    public String algorithm;
    public String serialNumber;
    public String subject;
    public String issuer;
    public String keyType;
    public int keyLength;
    public long certificateId;

src/java.base/share/classes/sun/security/jca/JCAUtil.java:

        SecureRandom result = def;
        if (result == null) {
            synchronized (JCAUtil.class) {
                result = def;
                if (result == null) {
                    def = result = new SecureRandom();
                }
            }
        }
        return result;
    }

    public static void tryCommitCertEvent(Certificate cert) {
        if ((X509CertificateEvent.isTurnedOn() || EventHelper.isLoggingSecurity()) &&
                (cert instanceof X509Certificate x509)) {
            PublicKey pKey = x509.getPublicKey();
            String algId = x509.getSigAlgName();
            String serNum = x509.getSerialNumber().toString(16);
            String subject = x509.getSubjectX500Principal().toString();
            String issuer = x509.getIssuerX500Principal().toString();
            String keyType = pKey.getAlgorithm();
            int length = KeyUtil.getKeySize(pKey);
            int hashCode = x509.hashCode();
            long certifcateId = Integer.toUnsignedLong(hashCode);
            long beginDate = x509.getNotBefore().getTime();
            long endDate = x509.getNotAfter().getTime();
            if (X509CertificateEvent.isTurnedOn()) {
                X509CertificateEvent xce = new X509CertificateEvent();
                xce.algorithm = algId;
                xce.serialNumber = serNum;
                xce.subject = subject;
                xce.issuer = issuer;
                xce.keyType = keyType;
                xce.keyLength = length;
                xce.certificateId = certifcateId;
                xce.validFrom = beginDate;
                xce.validUntil = endDate;
                xce.commit();
            }

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
algorithm string Signature Algorithm
serialNumber string Serial Number
subject string Subject
issuer string Issuer
keyType string Key Type
keyLength int Key Length
certificateId ulong: certificateId Certificate Id
validFrom long: epochmillis Valid From
validUntil long: epochmillis Valid Until

Examples 3
algorithm string
SHA1withDSA
certificateId ulong: certificateId
3045411335
issuer string
CN=Unknown, OU=Unknown, O=Unknown, L=Unknown, ST=Unknown, C=Unknown
keyLength int
1024
keyType string
DSA
serialNumber string
46:10:1f:71
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
185
lineNumber int
128
method Method
descriptor string
(Ljava/security/cert/Certificate;)V
hidden boolean
false
modifiers int
9
name string
tryCommitCertEvent
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
sun/security/jca/JCAUtil
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
sun/security/jca
type FrameType
Interpreted
truncated boolean
true
startTime long: millis
347080797036
subject string
CN=Unknown, OU=Unknown, O=Unknown, L=Unknown, ST=Unknown, C=Unknown
validFrom long: epochmillis
1175461745000
validUntil long: epochmillis
4329061745000
algorithm string
SHA1withDSA
certificateId ulong: certificateId
3045411335
issuer string
CN=Unknown, OU=Unknown, O=Unknown, L=Unknown, ST=Unknown, C=Unknown
keyLength int
1024
keyType string
DSA
serialNumber string
46:10:1f:71
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
185
lineNumber int
128
method Method
descriptor string
(Ljava/security/cert/Certificate;)V
hidden boolean
false
modifiers int
9
name string
tryCommitCertEvent
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
sun/security/jca/JCAUtil
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
sun/security/jca
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
429649157311
subject string
CN=Unknown, OU=Unknown, O=Unknown, L=Unknown, ST=Unknown, C=Unknown
validFrom long: epochmillis
1175461745000
validUntil long: epochmillis
4329061745000
algorithm string
SHA1withDSA
certificateId ulong: certificateId
3045411335
issuer string
CN=Unknown, OU=Unknown, O=Unknown, L=Unknown, ST=Unknown, C=Unknown
keyLength int
1024
keyType string
DSA
serialNumber string
46:10:1f:71
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
185
lineNumber int
128
method Method
descriptor string
(Ljava/security/cert/Certificate;)V
hidden boolean
false
modifiers int
9
name string
tryCommitCertEvent
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
sun/security/jca/JCAUtil
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
sun/security/jca
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
465282108322
subject string
CN=Unknown, OU=Unknown, O=Unknown, L=Unknown, ST=Unknown, C=Unknown
validFrom long: epochmillis
1175461745000
validUntil long: epochmillis
4329061745000

TLSHandshake

startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/TLSHandshakeEvent.java

Category: Java Development Kit / Security

Excludes in stack trace: sun.security.ssl.Finished::recordEvent

Parameters used in TLS Handshake

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/TLSHandshakeEvent.java:

@Category({"Java Development Kit", "Security"})
@Label("TLS Handshake")
@Name("jdk.TLSHandshake")
@Description("Parameters used in TLS Handshake")
@MirrorEvent(className = "jdk.internal.event.TLSHandshakeEvent")
@RemoveFields("duration")
@StackFilter("sun.security.ssl.Finished::recordEvent")
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/MirrorEvents.java:

public final class MirrorEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class,
        ErrorThrownEvent.class,
        ExceptionStatisticsEvent.class,
        ExceptionThrownEvent.class,
    };

src/java.base/share/classes/jdk/internal/event/TLSHandshakeEvent.java:

package jdk.internal.event;

/**
 * Event recording details of successful TLS handshakes.
 */

public final class TLSHandshakeEvent extends Event {
    public String peerHost;
    public int peerPort;
    public String protocolVersion;
    public String cipherSuite;
    public long certificateId;
}

src/java.base/share/classes/sun/security/ssl/Finished.java:

            // May need to retransmit the last flight for DTLS.
            if (!shc.sslContext.isDTLS()) {
                shc.conContext.finishHandshake();
            }
            recordEvent(shc.conContext.conSession);

            //
            // produce
            NewSessionTicket.t13PosthandshakeProducer.produce(shc);
        }
    }

    private static void recordEvent(SSLSessionImpl session) {
        TLSHandshakeEvent event = new TLSHandshakeEvent();
        if (event.shouldCommit() || EventHelper.isLoggingSecurity()) {
            int hash = 0;
            try {
                // use hash code for Id
                hash = session
                        .getCertificateChain()[0]
                        .hashCode();
            } catch (SSLPeerUnverifiedException e) {
                 // not verified msg
            }
            long peerCertificateId = Integer.toUnsignedLong(hash);

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
peerHost string Peer Host
peerPort int Peer Port
protocolVersion string Protocol Version
cipherSuite string Cipher Suite
certificateId ulong: certificateId Certificate Id Peer Certificate Id

SecurityPropertyModification

startTime duration stackTrace 11 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/SecurityPropertyModificationEvent.java

Category: Java Development Kit / Security

Excludes in stack trace: java.security.Security::setProperty

Modification of Security property

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/SecurityPropertyModificationEvent.java:

package jdk.jfr.events;

import jdk.jfr.*;
import jdk.jfr.internal.MirrorEvent;
import jdk.jfr.internal.RemoveFields;

@Category({"Java Development Kit", "Security"})
@Label("Security Property Modification")
@Name("jdk.SecurityPropertyModification")
@Description("Modification of Security property")
@MirrorEvent(className = "jdk.internal.event.SecurityPropertyModificationEvent")
@RemoveFields("duration")
@StackFilter({"java.security.Security::setProperty"})
public final class SecurityPropertyModificationEvent extends AbstractJDKEvent {
    @Label("Key")
    public String key;

    @Label("Value")
    public String value;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/MirrorEvents.java:

public final class MirrorEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,
        X509ValidationEvent.class,

src/java.base/share/classes/jdk/internal/event/SecurityPropertyModificationEvent.java:

package jdk.internal.event;

/**
 * Event details relating to the modification of a Security property.
 */

public final class SecurityPropertyModificationEvent extends Event {
    public String key;
    public String value;
}

src/java.base/share/classes/java/security/Security.java:

     *          if a security manager exists and its {@link
     *          java.lang.SecurityManager#checkPermission} method
     *          denies access to set the specified security property value
     * @throws  NullPointerException if key or datum is {@code null}
     *
     * @see #getProperty
     * @see java.security.SecurityPermission
     */
    public static void setProperty(String key, String datum) {
        check("setProperty." + key);
        props.put(key, datum);
        invalidateSMCache(key);  /* See below. */

        SecurityPropertyModificationEvent spe = new SecurityPropertyModificationEvent();
        // following is a no-op if event is disabled
        spe.key = key;
        spe.value = datum;
        spe.commit();

        if (EventHelper.isLoggingSecurity()) {
            EventHelper.logSecurityPropertyEvent(key, datum);
        }
    }

    /*

Configuration enabled stackTrace
profiling false true
default false true

Field Type Description
key string Key
value string Value

InitialSecurityProperty

profiling default startTime duration stackTrace 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/InitialSecurityPropertyEvent.java

Category: Java Development Kit / Security

Initial Security Properties

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/InitialSecurityPropertyEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;

@Category({"Java Development Kit", "Security"})
@Label("Initial Security Property")
@Name("jdk.InitialSecurityProperty")
@Description("Initial Security Properties")
public final class InitialSecurityPropertyEvent extends AbstractPeriodicEvent {
    @Label("Key")
    public String key;

    @Label("Value")
    public String value;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.SecurityProviderServiceEvent.class,
        jdk.internal.event.SocketReadEvent.class,
        jdk.internal.event.SocketWriteEvent.class,
        jdk.internal.event.ThreadSleepEvent.class,
        jdk.internal.event.TLSHandshakeEvent.class,
        jdk.internal.event.VirtualThreadStartEvent.class,
        jdk.internal.event.VirtualThreadEndEvent.class,
        jdk.internal.event.VirtualThreadPinnedEvent.class,
        jdk.internal.event.VirtualThreadSubmitFailedEvent.class,
        jdk.internal.event.X509CertificateEvent.class,
        jdk.internal.event.X509ValidationEvent.class,
        DirectBufferStatisticsEvent.class,
        InitialSecurityPropertyEvent.class,
    };

    // This is a list of the classes with instrumentation code that should be applied.
    private static final Class<?>[] instrumentationClasses = new Class<?>[] {
        FileInputStreamInstrumentor.class,
        FileOutputStreamInstrumentor.class,
        RandomAccessFileInstrumentor.class,
        FileChannelImplInstrumentor.class
    };

    private static final Class<?>[] targetClasses = new Class<?>[instrumentationClasses.length];

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

    private static final Runnable emitInitialSecurityProperties = JDKEvents::emitInitialSecurityProperties;
    private static Metrics containerMetrics = null;
    private static boolean initializationTriggered;

    @SuppressWarnings("unchecked")
    public static synchronized void initialize() {
        try {
            if (initializationTriggered == false) {
                for (Class<?> eventClass : eventClasses) {
                    SecuritySupport.registerEvent((Class<? extends Event>) eventClass);
                }
                PeriodicEvents.addJDKEvent(jdk.internal.event.ExceptionStatisticsEvent.class, emitExceptionStatistics);
                PeriodicEvents.addJDKEvent(DirectBufferStatisticsEvent.class, emitDirectBufferStatistics);
                PeriodicEvents.addJDKEvent(InitialSecurityPropertyEvent.class, emitInitialSecurityProperties);

                initializeContainerEvents();
                ThrowableTracer.enable();
                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:

        PeriodicEvents.removeEvent(emitContainerConfiguration);
        PeriodicEvents.removeEvent(emitContainerCPUUsage);
        PeriodicEvents.removeEvent(emitContainerCPUThrottling);
        PeriodicEvents.removeEvent(emitContainerMemoryUsage);
        PeriodicEvents.removeEvent(emitContainerIOUsage);
    }

    private static void emitDirectBufferStatistics() {
        DirectBufferStatisticsEvent e = new DirectBufferStatisticsEvent();
        e.commit();
    }

    private static void emitInitialSecurityProperties() {
        Properties p = SharedSecrets.getJavaSecurityPropertiesAccess().getInitialProperties();
        if (p != null) {
            for (String key : p.stringPropertyNames()) {
                InitialSecurityPropertyEvent e = new InitialSecurityPropertyEvent();
                e.key = key;
                e.value = p.getProperty(key);
                e.commit();
            }
        }
    }
}

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
key string Key
value string Value

Examples 3
key string
http.auth.digest.disabledAlgorithms
stackTrace StackTrace
null
startTime long: millis
400299625122
value string
MD5, SHA-1
key string
krb5.kdc.bad.policy
stackTrace StackTrace
null
startTime long: millis
358469125686
value string
tryLast
key string
ssl.KeyManagerFactory.algorithm
stackTrace StackTrace
null
startTime long: millis
297165193365
value string
SunX509

Operating System

OSInformation

profiling default startTime duration end of every chunk 11 17 21 25 26 27 graal vm

Category: Operating System

Description of the OS the JVM runs on, for example, a uname-like output

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  event.set_jvmVersion(VM_Version::internal_vm_info_string());
  event.set_javaArguments(Arguments::java_command());
  event.set_jvmArguments(Arguments::jvm_args());
  event.set_jvmFlags(Arguments::jvm_flags());
  event.set_jvmStartTime(Management::vm_init_done_time());
  event.set_pid(os::current_process_id());
  event.commit();
 }

TRACE_REQUEST_FUNC(OSInformation) {
  ResourceMark rm;
  char* os_name = NEW_RESOURCE_ARRAY(char, 2048);
  JfrOSInterface::os_version(&os_name);
  EventOSInformation event;
  event.set_osVersion(os_name);
  event.commit();
}

TRACE_REQUEST_FUNC(VirtualizationInformation) {
  EventVirtualizationInformation event;
  event.set_name(JfrOSInterface::virtualization_name());
  event.commit();
}

TRACE_REQUEST_FUNC(ModuleRequire) {

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
osVersion string OS Version

Examples 3
osVersion string
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=24.04 DISTRIB_CODENAME=noble DISTRIB_DESCRIPTION="Ubuntu 24.04.3 LTS" uname: Linux 6.11.0-1018-azure #18~24.04.1-Ubuntu SMP Sat Jun 28 04:46:03 UTC 2025 x86_64 libc: glibc 2.39 NPTL 2.39
startTime long: millis
319552582037
osVersion string
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=24.04 DISTRIB_CODENAME=noble DISTRIB_DESCRIPTION="Ubuntu 24.04.3 LTS" uname: Linux 6.11.0-1018-azure #18~24.04.1-Ubuntu SMP Sat Jun 28 04:46:03 UTC 2025 x86_64 libc: glibc 2.39 NPTL 2.39
startTime long: millis
454792399724
osVersion string
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=24.04 DISTRIB_CODENAME=noble DISTRIB_DESCRIPTION="Ubuntu 24.04.3 LTS" uname: Linux 6.11.0-1018-azure #18~24.04.1-Ubuntu SMP Sat Jun 28 04:46:03 UTC 2025 x86_64 libc: glibc 2.39 NPTL 2.39
startTime long: millis
351480055383

VirtualizationInformation

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Operating System

Description of the virtualization technology the JVM runs on

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  event.commit();
 }

TRACE_REQUEST_FUNC(OSInformation) {
  ResourceMark rm;
  char* os_name = NEW_RESOURCE_ARRAY(char, 2048);
  JfrOSInterface::os_version(&os_name);
  EventOSInformation event;
  event.set_osVersion(os_name);
  event.commit();
}

TRACE_REQUEST_FUNC(VirtualizationInformation) {
  EventVirtualizationInformation event;
  event.set_name(JfrOSInterface::virtualization_name());
  event.commit();
}

TRACE_REQUEST_FUNC(ModuleRequire) {
  JfrModuleEvent::generate_module_dependency_events();
}

TRACE_REQUEST_FUNC(ModuleExport) {
  JfrModuleEvent::generate_module_export_events();
}

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
name string Name

Examples 3
name string
Hyper-V virtualization
startTime long: millis
367057051913
name string
Hyper-V virtualization
startTime long: millis
475971841559
name string
Hyper-V virtualization
startTime long: millis
309625723255

InitialEnvironmentVariable

profiling default startTime end of every chunk 11 17 21 25 26 27 graal vm

Category: Operating System

Key-value pairs for environment variables at JVM startup

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrOSInterface.cpp:

  } else if (vrt == PowerFullPartitionMode) {
    return "Power full partition";
  }

  return "No virtualization detected";
}

int JfrOSInterface::generate_initial_environment_variable_events() {
  if (os::get_environ() == nullptr) {
    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 != nullptr; p++) {
      char* variable = *p;
      char* equal_sign = strchr(variable, '=');
      if (equal_sign != nullptr) {
        // Extract key/value
        ResourceMark rm;
        ptrdiff_t key_length = equal_sign - variable;
        char* key = NEW_RESOURCE_ARRAY(char, key_length + 1);
        char* value = equal_sign + 1;
        strncpy(key, variable, key_length);
        key[key_length] = '\0';
        EventInitialEnvironmentVariable event(UNTIMED);
        event.set_starttime(time_stamp);
        event.set_endtime(time_stamp);
        event.set_key(key);
        event.set_value(value);
        event.commit();
      }
    }
  }
  return OS_OK;
}

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
key string Key
value string Value

Examples 3
key string
SYSTEMD_EXEC_PID
startTime long: millis
296986086879
value string
2039
key string
GITHUB_EVENT_NAME
startTime long: millis
351480059601
value string
schedule
key string
GITHUB_REF_TYPE
startTime long: millis
398047145084
value string
branch

SystemProcess

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Operating System

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

    while (processes != nullptr) {
      SystemProcess* tmp = processes;
      const char* info = processes->command_line();
      if (info == nullptr) {
         info = processes->path();
      }
      if (info == nullptr) {
         info = processes->name();
      }
      if (info == nullptr) {
         info = "?";
      }
      jio_snprintf(pid_buf, sizeof(pid_buf), "%d", processes->pid());
      EventSystemProcess event(UNTIMED);
      event.set_pid(pid_buf);
      event.set_commandLine(info);
      event.set_starttime(start_time);
      event.set_endtime(end_time);
      event.commit();
      processes = processes->next();
      delete tmp;
    }
  }
}

Configuration enabled period
profiling true endChunk
default true endChunk

Field Type Description
pid string Process Identifier
commandLine string Command Line

CPUInformation

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Operating System / Processor

Characteristics and descriptions of the processor(s) the JVM is running on

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

TRACE_REQUEST_FUNC(CPUInformation) {
  CPUInformation cpu_info;
  int ret_val = JfrOSInterface::cpu_information(cpu_info);
  if (ret_val == OS_ERR) {
    log_debug(jfr, system)( "Unable to generate requestable event CPUInformation");
    return;
  }
  if (ret_val == FUNCTIONALITY_NOT_IMPLEMENTED) {
     return;
  }
  if (ret_val == OS_OK) {
    EventCPUInformation event;
    event.set_cpu(cpu_info.cpu_name());
    event.set_description(cpu_info.cpu_description());
    event.set_sockets(cpu_info.number_of_sockets());
    event.set_cores(cpu_info.number_of_cores());
    event.set_hwThreads(cpu_info.number_of_hardware_threads());
    event.commit();
  }
}

TRACE_REQUEST_FUNC(CPULoad) {
  double u = 0; // user time

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
cpu string Type
description string Description
sockets uint Sockets
cores uint Cores
hwThreads uint Hardware Threads

Examples 3
cores uint
16
cpu string
AMD Unknown x86 (HT) SSE SSE2 SSE3 SSSE3 SSE4.1 SSE4.2 SSE4A AMD64
description string
Brand: AMD EPYC 7763 64-Core Processor , Vendor: AuthenticAMD Family: Unknown x86 (0x19), Model: <unknown> (0x1), Stepping: 0x1 Ext. family: 0xa, Ext. model: 0x0, Type: 0x0, Signature: 0x00a00f11 Features: ebx: 0x01100800, ecx: 0xfeda3203, edx: 0x178bfbff Ext. features: eax: 0x00a00f1
hwThreads uint
4
sockets uint
1
startTime long: millis
389249319311
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
296986100945
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
408179913692

CPUTimeStampCounter

profiling default startTime duration end of every chunk 11 17 21 25 26 27

Category: Operating System / Processor

Information about the CPU time stamp mechanism / (RD)TSC

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

TRACE_REQUEST_FUNC(ThreadCPULoad) {
  JfrThreadCPULoadEvent::send_events();
}

TRACE_REQUEST_FUNC(CompilerQueueUtilization) {
  JfrCompilerQueueUtilization::send_events();
}

TRACE_REQUEST_FUNC(NetworkUtilization) {
  JfrNetworkUtilization::send_events();
}

TRACE_REQUEST_FUNC(CPUTimeStampCounter) {
  EventCPUTimeStampCounter event;
  event.set_fastTimeEnabled(JfrTime::is_ft_enabled());
  event.set_fastTimeAutoEnabled(JfrTime::is_ft_supported());
  event.set_osFrequency(os::elapsed_frequency());
  event.set_fastTimeFrequency(JfrTime::frequency());
  event.commit();
}

TRACE_REQUEST_FUNC(SystemProcess) {
  char pid_buf[16];
  SystemProcess* processes = nullptr;
  int num_of_processes = 0;

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
fastTimeEnabled boolean Fast Time
fastTimeAutoEnabled boolean Trusted Platform
osFrequency long: hertz OS Frequency
fastTimeFrequency long: hertz Fast Time Frequency

Examples 3
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
451229872700
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
311699191333
fastTimeAutoEnabled boolean
true
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
416836178164

CPULoad

profiling default startTime duration every chunk 11 17 21 25 26 27

Category: Operating System / Processor

Information about the recent CPU usage of the JVM process

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

  double t = 0; // total time
  int ret_val = OS_ERR;
  {
    // Can take some time on certain platforms, especially under heavy load.
    // Transition to native to avoid unnecessary stalls for pending safepoint synchronizations.
    ThreadToNativeFromVM transition(JavaThread::current());
    ret_val = JfrOSInterface::cpu_loads_process(&u, &s, &t);
  }
  if (ret_val == OS_ERR) {
    log_debug(jfr, system)( "Unable to generate requestable event CPULoad");
    return;
  }
  if (ret_val == OS_OK) {
    EventCPULoad event;
    event.set_jvmUser((float)u);
    event.set_jvmSystem((float)s);
    event.set_machineTotal((float)t);
    event.commit();
  }
}

TRACE_REQUEST_FUNC(ThreadCPULoad) {
  JfrThreadCPULoadEvent::send_events();
}

Configuration enabled period
profiling true 1000 ms
default true 1000 ms

Field Type Description
jvmUser float: percentage JVM User
jvmSystem float: percentage JVM System
machineTotal float: percentage Machine Total

Examples 3
jvmSystem float: percentage
0.025
jvmUser float: percentage
0.3925
machineTotal float: percentage
0.42
startTime long: millis
377799808601
jvmSystem float: percentage
0.06467662
jvmUser float: percentage
0.9328358
machineTotal float: percentage
0.99751246
startTime long: millis
505182575133
jvmSystem float: percentage
0.011655011
jvmUser float: percentage
0.9114219
machineTotal float: percentage
0.9230769
startTime long: millis
452557123696

ThreadCPULoad

profiling default startTime duration eventThread every chunk 11 17 21 25 26 27 graal vm

Category: Operating System / Processor

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrThreadCPULoadEvent.hpp:

#ifndef SHARE_JFR_PERIODIC_JFRTHREADCPULOADEVENT_HPP
#define SHARE_JFR_PERIODIC_JFRTHREADCPULOADEVENT_HPP

#include "jni.h"
#include "memory/allStatic.hpp"

class JavaThread;
class EventThreadCPULoad;

class JfrThreadCPULoadEvent : public AllStatic {
  static int _last_active_processor_count;
 public:
  static jlong get_wallclock_time();
  static int get_processor_count();
  static bool update_event(EventThreadCPULoad& event, JavaThread* thread, jlong cur_wallclock_time, int processor_count);
  static void send_events();
  static void send_event_for_thread(JavaThread* jt);
};

#endif // SHARE_JFR_PERIODIC_JFRTHREADCPULOADEVENT_HPP

src/hotspot/share/jfr/periodic/jfrThreadCPULoadEvent.cpp:

int JfrThreadCPULoadEvent::get_processor_count() {
  int cur_processor_count = os::active_processor_count();
  int last_processor_count = _last_active_processor_count;
  _last_active_processor_count = cur_processor_count;

  // If the number of processors decreases, we don't know at what point during
  // the sample interval this happened, so use the largest number to try
  // to avoid percentages above 100%
  return MAX2(cur_processor_count, last_processor_count);
}

// Returns false if the thread has not been scheduled since the last call to updateEvent
// (i.e. the delta for both system and user time is 0 milliseconds)
bool JfrThreadCPULoadEvent::update_event(EventThreadCPULoad& event, JavaThread* thread, jlong cur_wallclock_time, int processor_count) {
  JfrThreadLocal* const tl = thread->jfr_thread_local();

  jlong cur_cpu_time = os::thread_cpu_time(thread, true);
  jlong prev_cpu_time = tl->get_cpu_time();

  jlong prev_wallclock_time = tl->get_wallclock_time();
  tl->set_wallclock_time(cur_wallclock_time);

  // Threshold of 1 ms
  if (cur_cpu_time - prev_cpu_time < 1 * NANOSECS_PER_MILLISEC) {
    return false;

src/hotspot/share/jfr/periodic/jfrThreadCPULoadEvent.cpp:

void JfrThreadCPULoadEvent::send_events() {
  Thread* periodic_thread = Thread::current();
  traceid periodic_thread_id = JfrThreadLocal::thread_id(periodic_thread);
  const int processor_count = JfrThreadCPULoadEvent::get_processor_count();
  JfrTicks event_time = JfrTicks::now();
  jlong cur_wallclock_time = JfrThreadCPULoadEvent::get_wallclock_time();

  JfrJavaThreadIterator iter;
  int number_of_threads = 0;
  while (iter.has_next()) {
    JavaThread* const jt = iter.next();
    assert(jt != nullptr, "invariant");
    ++number_of_threads;
    EventThreadCPULoad event(UNTIMED);
    if (JfrThreadCPULoadEvent::update_event(event, jt, cur_wallclock_time, processor_count)) {
      event.set_starttime(event_time);
      event.set_endtime(event_time);
      if (jt != periodic_thread) {
        // Commit reads the thread id from this thread's trace data, so put it there temporarily
        JfrThreadLocal::impersonate(periodic_thread, JFR_JVM_THREAD_ID(jt));
      } else {
        JfrThreadLocal::impersonate(periodic_thread, periodic_thread_id);
      }
      event.commit();
    }
  }
  log_trace(jfr)("Measured CPU usage for %d threads in %.3f milliseconds", number_of_threads,
    (double)(JfrTicks::now() - event_time).milliseconds());
  JfrThreadLocal::stop_impersonating(periodic_thread);
}

void JfrThreadCPULoadEvent::send_event_for_thread(JavaThread* jt) {
  EventThreadCPULoad event;
  if (event.should_commit()) {
    if (update_event(event, jt, get_wallclock_time(), get_processor_count())) {
      event.commit();
    }
  }
}

Configuration enabled period
profiling true 10 s
default true 10 s

Field Type Description
user float: percentage User Mode CPU Load User mode thread CPU load
system float: percentage System Mode CPU Load System mode thread CPU load

Examples 3
startTime long: millis
425596847220
system float: percentage
2.7296948E-4
user float: percentage
0.03941325
startTime long: millis
337845703299
system float: percentage
1.5257926E-4
user float: percentage
0.0
startTime long: millis
452285378737
system float: percentage
0.0
user float: percentage
3.174743E-5

ThreadContextSwitchRate

profiling default startTime duration every chunk 11 17 21 25 26 27

Category: Operating System / Processor

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

    // Can take some time on certain platforms, especially under heavy load.
    // Transition to native to avoid unnecessary stalls for pending safepoint synchronizations.
    ThreadToNativeFromVM transition(JavaThread::current());
    ret_val = JfrOSInterface::context_switch_rate(&rate);
  }
  if (ret_val == OS_ERR) {
    log_debug(jfr, system)( "Unable to generate requestable event ThreadContextSwitchRate");
    return;
  }
  if (ret_val == FUNCTIONALITY_NOT_IMPLEMENTED) {
    return;
  }
  if (ret_val == OS_OK) {
    EventThreadContextSwitchRate event;
    event.set_switchRate((float)rate + 0.0f);
    event.commit();
  }
}

#define SEND_FLAGS_OF_TYPE(eventType, flagType)                   \
  do {                                                            \
    JVMFlag *flag = JVMFlag::flags;                               \
    while (flag->name() != nullptr) {                             \
      if (flag->is_ ## flagType()) {                              \
        if (flag->is_unlocked()) {                                \

Configuration enabled period
profiling true 10 s
default true 10 s

Field Type Description
switchRate float: hertz Switch Rate Number of context switches per second

Examples 3
startTime long: millis
476374506171
switchRate float: hertz
4374.2896
startTime long: millis
440240395602
switchRate float: hertz
5556.799
startTime long: millis
340962707439
switchRate float: hertz
2961.711

NetworkUtilization

profiling default startTime every chunk 11 17 21 25 26 27

Category: Operating System / Network

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrNetworkUtilization.cpp:

  static JfrTicks last_sample_instant;
  const JfrTicks cur_time = JfrTicks::now();
  if (cur_time > last_sample_instant) {
    const JfrTickspan interval = cur_time - last_sample_instant;
    for (NetworkInterface *cur = network_interfaces; cur != nullptr; cur = cur->next()) {
      InterfaceEntry& entry = get_entry(cur);
      const uint64_t current_bytes_in = cur->get_bytes_in();
      const uint64_t current_bytes_out = cur->get_bytes_out();
      const uint64_t read_rate = rate_per_second(current_bytes_in, entry.bytes_in, interval);
      const uint64_t write_rate = rate_per_second(current_bytes_out, entry.bytes_out, interval);
      if (read_rate > 0 || write_rate > 0) {
        write_interface_constant(entry);
        EventNetworkUtilization event(UNTIMED);
        event.set_starttime(cur_time);
        event.set_endtime(cur_time);
        event.set_networkInterface(entry.id);
        event.set_readRate(8 * read_rate);
        event.set_writeRate(8 * write_rate);
        event.commit();
      }
      // update existing entry with new values
      entry.bytes_in = current_bytes_in;
      entry.bytes_out = current_bytes_out;
    }

Configuration enabled period
profiling true 5 s
default true 5 s

Field Type Description
networkInterface NetworkInterfaceName Network Interface Network Interface Name
readRate long: bits-per-second Read Rate Number of incoming bits per second
writeRate long: bits-per-second Write Rate Number of outgoing bits per second

Examples 3
networkInterface NetworkInterfaceName
eth0
readRate long: bits-per-second
7280
startTime long: millis
346986237277
writeRate long: bits-per-second
37640
networkInterface NetworkInterfaceName
eth0
readRate long: bits-per-second
4912
startTime long: millis
446353360793
writeRate long: bits-per-second
10296
networkInterface NetworkInterfaceName
enP36980s1
readRate long: bits-per-second
1072
startTime long: millis
459553448986
writeRate long: bits-per-second
12992

PhysicalMemory

profiling default startTime duration every chunk 11 17 21 25 26 27 graal vm

Category: Operating System / Memory

OS Physical Memory

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/hotspot/share/jfr/periodic/jfrPeriodic.cpp:

 *  PhysicalMemory event represents:
 *
 *  @totalSize == The amount of physical memory (hw) installed and reported by the OS, in bytes.
 *  @usedSize  == The amount of physical memory currently in use in the system (reserved/committed), in bytes.
 *
 *  Both fields are systemwide, i.e. represents the entire OS/HW environment.
 *  These fields do not include virtual memory.
 *
 *  If running inside a guest OS on top of a hypervisor in a virtualized environment,
 *  the total memory reported is the amount of memory configured for the guest OS by the hypervisor.
 */
TRACE_REQUEST_FUNC(PhysicalMemory) {
  u8 totalPhysicalMemory = os::physical_memory();
  EventPhysicalMemory event;
  event.set_totalSize(totalPhysicalMemory);
  event.set_usedSize(totalPhysicalMemory - os::available_memory());
  event.commit();
}

TRACE_REQUEST_FUNC(JavaThreadStatistics) {
  EventJavaThreadStatistics event;
  event.set_activeCount(ThreadService::get_live_thread_count());
  event.set_daemonCount(ThreadService::get_daemon_thread_count());
  event.set_accumulatedCount(ThreadService::get_total_thread_count());
  event.set_peakCount(ThreadService::get_peak_thread_count());

Configuration enabled period
profiling true everyChunk
default true everyChunk

Field Type Description
totalSize ulong: bytes Total Size Total amount of physical memory available to OS
usedSize ulong: bytes Used Size Total amount of physical memory in use

Examples 3
startTime long: millis
487381391971
totalSize ulong: bytes
16767533056
usedSize ulong: bytes
4091154432
startTime long: millis
373259115228
totalSize ulong: bytes
16771862528
usedSize ulong: bytes
3955011584
startTime long: millis
358305538183
totalSize ulong: bytes
16771862528
usedSize ulong: bytes
5830254592

ProcessStart

profiling default startTime duration stackTrace 15 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ProcessStartEvent.java

Category: Operating System

Excludes in stack trace: java.lang.ProcessBuilder, java.lang.Runtime::exec

Operating system process started

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/ProcessStartEvent.java:

@Category({"Operating System"})
@Label("Process Start")
@Name("jdk.ProcessStart")
@Description("Operating system process started")
@MirrorEvent(className = "jdk.internal.event.ProcessStartEvent")
@RemoveFields("duration")
@StackFilter({"java.lang.ProcessBuilder", "java.lang.Runtime::exec"})
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/MirrorEvents.java:

public final class MirrorEvents {
    private static final Class<?>[] mirrorEventClasses = {
        DeserializationEvent.class,
        ProcessStartEvent.class,
        SecurityPropertyModificationEvent.class,
        SecurityProviderServiceEvent.class,
        SocketReadEvent.class,
        SocketWriteEvent.class,
        ThreadSleepEvent.class,
        TLSHandshakeEvent.class,
        VirtualThreadStartEvent.class,
        VirtualThreadEndEvent.class,
        VirtualThreadPinnedEvent.class,
        VirtualThreadSubmitFailedEvent.class,
        X509CertificateEvent.class,

src/java.base/share/classes/jdk/internal/event/ProcessStartEvent.java:

package jdk.internal.event;

/**
 * Event for the start of an OS procsss
 */

public final class ProcessStartEvent extends Event {
    public long pid;
    public String directory;
    public String command;
}

src/java.base/share/classes/java/lang/ProcessBuilder.java:

        for (String s : cmdarray) {
            if (s.indexOf('\u0000') >= 0) {
                throw new IOException("invalid null character in command");
            }
        }

        try {
            Process process = ProcessImpl.start(cmdarray,
                                     environment,
                                     dir,
                                     redirects,
                                     redirectErrorStream);
            ProcessStartEvent event = new ProcessStartEvent();
            if (event.isEnabled()) {
                event.directory = dir;
                event.command = String.join(" ", cmdarray);
                event.pid = process.pid();
                event.commit();
            }
            // Racy initialization for logging; errors in configuration may throw exceptions
            System.Logger logger = LOGGER;
            if (logger == null) {
                LOGGER = logger = System.getLogger("java.lang.ProcessBuilder");
            }

Configuration enabled stackTrace
profiling true true
default true true

Field Type Description
pid long Process Id
directory string Directory
command string Command

Examples 3
command string
setsid bash -c echo $$
directory string
null
pid long
4113
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
232
lineNumber int
1154
method Method
descriptor string
([Ljava/lang/ProcessBuilder$Redirect;)Ljava/lang/Process;
hidden boolean
false
modifiers int
2
name string
start
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/ProcessBuilder
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
427720724115
command string
setsid bash -c echo $$
directory string
null
pid long
4089
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
232
lineNumber int
1154
method Method
descriptor string
([Ljava/lang/ProcessBuilder$Redirect;)Ljava/lang/Process;
hidden boolean
false
modifiers int
2
name string
start
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/ProcessBuilder
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
463439181127
command string
rm -rf /home/runner/work/jfrevents/jfrevents/harness-004314-6346519699961129921/apache-spark/log-regression/blockmgr-b939d0ce-0f51-417e-9ede-00a6b808671c
directory string
null
pid long
4258
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
232
lineNumber int
1154
method Method
descriptor string
([Ljava/lang/ProcessBuilder$Redirect;)Ljava/lang/Process;
hidden boolean
false
modifiers int
2
name string
start
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/lang/ProcessBuilder
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
354295335417

ContainerCPUThrottling

profiling default startTime duration stackTrace 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ContainerCPUThrottlingEvent.java

Category: Operating System / Processor

Container CPU throttling related information

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/ContainerCPUThrottlingEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.Timespan;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "ContainerCPUThrottling")
@Label("CPU Throttling")
@Category({"Operating System", "Processor"})
@Description("Container CPU throttling related information")
public class ContainerCPUThrottlingEvent extends AbstractPeriodicEvent {
  @Label("CPU Elapsed Slices")
  @Description("Number of time-slice periods that have elapsed if a CPU quota has been setup for the container")
  public long cpuElapsedSlices;

  @Label("CPU Throttled Slices")
  @Description("Number of time-slice periods that the CPU has been throttled or limited due to exceeding CPU quota")
  public long cpuThrottledSlices;

  @Label("CPU Throttled Time")
  @Description("Total time duration, in nanoseconds, that the CPU has been throttled or limited due to exceeding CPU quota")
  @Timespan

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

    private static void initializeContainerEvents() {
        if (JVM.isContainerized() ) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "JVM is containerized");
            containerMetrics = Container.metrics();
            if (containerMetrics != null) {
                Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "Container metrics are available");
            }
        }
        // The registration of events and hooks are needed to provide metadata,
        // even when not running in a container
        SecuritySupport.registerEvent(ContainerConfigurationEvent.class);
        SecuritySupport.registerEvent(ContainerCPUUsageEvent.class);
        SecuritySupport.registerEvent(ContainerCPUThrottlingEvent.class);
        SecuritySupport.registerEvent(ContainerMemoryUsageEvent.class);
        SecuritySupport.registerEvent(ContainerIOUsageEvent.class);

        PeriodicEvents.addJDKEvent(ContainerConfigurationEvent.class, emitContainerConfiguration);
        PeriodicEvents.addJDKEvent(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        PeriodicEvents.addJDKEvent(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        PeriodicEvents.addJDKEvent(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        PeriodicEvents.addJDKEvent(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void emitExceptionStatistics() {
        ThrowableTracer.emitStatistics();
    }

    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 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 {
        for (int i = 0; i < targetClasses.length; i++) {

Configuration enabled period
profiling true 30 s
default true 30 s

Field Type Description
cpuElapsedSlices long CPU Elapsed Slices Number of time-slice periods that have elapsed if a CPU quota has been setup for the container
cpuThrottledSlices long CPU Throttled Slices Number of time-slice periods that the CPU has been throttled or limited due to exceeding CPU quota
cpuThrottledTime long: nanos CPU Throttled Time Total time duration, in nanoseconds, that the CPU has been throttled or limited due to exceeding CPU quota

ContainerMemoryUsage

profiling default startTime duration stackTrace 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ContainerMemoryUsageEvent.java

Category: Operating System / Memory

Container memory usage related information

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/ContainerMemoryUsageEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.DataAmount;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "ContainerMemoryUsage")
@Label("Container Memory Usage")
@Category({"Operating System", "Memory"})
@Description("Container memory usage related information")
public final class ContainerMemoryUsageEvent extends AbstractPeriodicEvent {
    @Label("Memory Fail Count")
    @Description("Number of times that user memory requests in the container have exceeded the memory limit")
    public long memoryFailCount;

    @Label("Memory Usage")
    @Description("Amount of physical memory, in bytes, that is currently allocated in the current container")
    @DataAmount
    public long memoryUsage;

    @Label("Memory and Swap Usage")
    @Description("Amount of physical memory and swap space, in bytes, that is currently allocated in the current container")

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

    private static void initializeContainerEvents() {
        if (JVM.isContainerized() ) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "JVM is containerized");
            containerMetrics = Container.metrics();
            if (containerMetrics != null) {
                Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "Container metrics are available");
            }
        }
        // The registration of events and hooks are needed to provide metadata,
        // even when not running in a container
        SecuritySupport.registerEvent(ContainerConfigurationEvent.class);
        SecuritySupport.registerEvent(ContainerCPUUsageEvent.class);
        SecuritySupport.registerEvent(ContainerCPUThrottlingEvent.class);
        SecuritySupport.registerEvent(ContainerMemoryUsageEvent.class);
        SecuritySupport.registerEvent(ContainerIOUsageEvent.class);

        PeriodicEvents.addJDKEvent(ContainerConfigurationEvent.class, emitContainerConfiguration);
        PeriodicEvents.addJDKEvent(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        PeriodicEvents.addJDKEvent(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        PeriodicEvents.addJDKEvent(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        PeriodicEvents.addJDKEvent(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void emitExceptionStatistics() {
        ThrowableTracer.emitStatistics();
    }

    private static void emitContainerConfiguration() {
        if (containerMetrics != null) {
            ContainerConfigurationEvent t = new ContainerConfigurationEvent();
            t.containerType = containerMetrics.getProvider();

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

    private static void emitContainerCPUUsage() {
        if (containerMetrics != null) {
            ContainerCPUUsageEvent event = new ContainerCPUUsageEvent();

            event.cpuTime = containerMetrics.getCpuUsage();
            event.cpuSystemTime = containerMetrics.getCpuSystemUsage();
            event.cpuUserTime = containerMetrics.getCpuUserUsage();
            event.commit();
        }
    }
    private static void emitContainerMemoryUsage() {
        if (containerMetrics != null) {
            ContainerMemoryUsageEvent event = new ContainerMemoryUsageEvent();

            event.memoryFailCount = containerMetrics.getMemoryFailCount();
            event.memoryUsage = containerMetrics.getMemoryUsage();
            event.swapMemoryUsage = containerMetrics.getMemoryAndSwapUsage();
            event.commit();
        }
    }

    private static void emitContainerIOUsage() {
        if (containerMetrics != null) {
            ContainerIOUsageEvent event = new ContainerIOUsageEvent();

Configuration enabled period
profiling true 30 s
default true 30 s

Field Type Description
memoryFailCount long Memory Fail Count Number of times that user memory requests in the container have exceeded the memory limit
memoryUsage long: bytes Memory Usage Amount of physical memory, in bytes, that is currently allocated in the current container
swapMemoryUsage long: bytes Memory and Swap Usage Amount of physical memory and swap space, in bytes, that is currently allocated in the current container

ContainerConfiguration

profiling default startTime duration stackTrace 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ContainerConfigurationEvent.java

Category: Operating System

A set of container specific attributes

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/ContainerConfigurationEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "ContainerConfiguration")
@Label("Container Configuration")
@Category({"Operating System"})
@Description("A set of container specific attributes")
public final class ContainerConfigurationEvent extends AbstractPeriodicEvent {
    @Label("Container Type")
    @Description("Container type information")
    public String containerType;

    @Label("CPU Slice Period")
    @Description("Length of the scheduling period for processes within the container")
    @Timespan(Timespan.MICROSECONDS)
    public long cpuSlicePeriod;

    @Label("CPU Quota")
    @Description("Total available run-time allowed during each scheduling period for all tasks in the container")

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

    private static void initializeContainerEvents() {
        if (JVM.isContainerized() ) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "JVM is containerized");
            containerMetrics = Container.metrics();
            if (containerMetrics != null) {
                Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "Container metrics are available");
            }
        }
        // The registration of events and hooks are needed to provide metadata,
        // even when not running in a container
        SecuritySupport.registerEvent(ContainerConfigurationEvent.class);
        SecuritySupport.registerEvent(ContainerCPUUsageEvent.class);
        SecuritySupport.registerEvent(ContainerCPUThrottlingEvent.class);
        SecuritySupport.registerEvent(ContainerMemoryUsageEvent.class);
        SecuritySupport.registerEvent(ContainerIOUsageEvent.class);

        PeriodicEvents.addJDKEvent(ContainerConfigurationEvent.class, emitContainerConfiguration);
        PeriodicEvents.addJDKEvent(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        PeriodicEvents.addJDKEvent(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        PeriodicEvents.addJDKEvent(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        PeriodicEvents.addJDKEvent(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void emitExceptionStatistics() {
        ThrowableTracer.emitStatistics();
    }

    private static void emitContainerConfiguration() {
        if (containerMetrics != null) {
            ContainerConfigurationEvent t = new ContainerConfigurationEvent();
            t.containerType = containerMetrics.getProvider();
            t.cpuSlicePeriod = containerMetrics.getCpuPeriod();
            t.cpuQuota = containerMetrics.getCpuQuota();
            t.cpuShares = containerMetrics.getCpuShares();
            t.effectiveCpuCount = containerMetrics.getEffectiveCpuCount();
            t.memorySoftLimit = containerMetrics.getMemorySoftLimit();
            t.memoryLimit = containerMetrics.getMemoryLimit();
            t.swapMemoryLimit = containerMetrics.getMemoryAndSwapLimit();
            t.hostTotalMemory = JVM.hostTotalMemory();
            t.commit();
        }

Configuration enabled period
profiling true beginChunk
default true beginChunk

Field Type Description
containerType string Container Type Container type information
cpuSlicePeriod long: microseconds CPU Slice Period Length of the scheduling period for processes within the container
cpuQuota long: microseconds CPU Quota Total available run-time allowed during each scheduling period for all tasks in the container
cpuShares long CPU Shares Relative weighting of processes with the container used for prioritizing the scheduling of processes across all containers running on a host
effectiveCpuCount long Effective CPU Count Number of effective processors that this container has available to it
memorySoftLimit long: bytes Memory Soft Limit Hint to the operating system that allows groups to specify the minimum required amount of physical memory
memoryLimit long: bytes Memory Limit Maximum amount of physical memory that can be allocated in the container
swapMemoryLimit long: bytes Memory and Swap Limit Maximum amount of physical memory and swap space, in bytes, that can be allocated in the container
hostTotalMemory long: bytes 20+ Container Host Total Memory Total memory of the host running the container

ContainerCPUUsage

profiling default startTime duration stackTrace 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ContainerCPUUsageEvent.java

Category: Operating System / Processor

Container CPU usage related information

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/ContainerCPUUsageEvent.java:

package jdk.jfr.events;

import jdk.jfr.Category;
import jdk.jfr.Description;
import jdk.jfr.Label;
import jdk.jfr.Name;
import jdk.jfr.Timespan;
import jdk.jfr.internal.Type;

@Name(Type.EVENT_NAME_PREFIX + "ContainerCPUUsage")
@Label("CPU Usage")
@Category({"Operating System", "Processor"})
@Description("Container CPU usage related information")
public class ContainerCPUUsageEvent extends AbstractPeriodicEvent {
  @Label("CPU Time")
  @Description("Aggregate time consumed by all tasks in the container")
  @Timespan
  public long cpuTime;

  @Label("CPU User Time")
  @Description("Aggregate user time consumed by all tasks in the container")
  @Timespan
  public long cpuUserTime;

  @Label("CPU System Time")

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

    private static void initializeContainerEvents() {
        if (JVM.isContainerized() ) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "JVM is containerized");
            containerMetrics = Container.metrics();
            if (containerMetrics != null) {
                Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "Container metrics are available");
            }
        }
        // The registration of events and hooks are needed to provide metadata,
        // even when not running in a container
        SecuritySupport.registerEvent(ContainerConfigurationEvent.class);
        SecuritySupport.registerEvent(ContainerCPUUsageEvent.class);
        SecuritySupport.registerEvent(ContainerCPUThrottlingEvent.class);
        SecuritySupport.registerEvent(ContainerMemoryUsageEvent.class);
        SecuritySupport.registerEvent(ContainerIOUsageEvent.class);

        PeriodicEvents.addJDKEvent(ContainerConfigurationEvent.class, emitContainerConfiguration);
        PeriodicEvents.addJDKEvent(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        PeriodicEvents.addJDKEvent(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        PeriodicEvents.addJDKEvent(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        PeriodicEvents.addJDKEvent(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void emitExceptionStatistics() {
        ThrowableTracer.emitStatistics();
    }

    private static void emitContainerConfiguration() {
        if (containerMetrics != null) {

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

            t.cpuQuota = containerMetrics.getCpuQuota();
            t.cpuShares = containerMetrics.getCpuShares();
            t.effectiveCpuCount = containerMetrics.getEffectiveCpuCount();
            t.memorySoftLimit = containerMetrics.getMemorySoftLimit();
            t.memoryLimit = containerMetrics.getMemoryLimit();
            t.swapMemoryLimit = containerMetrics.getMemoryAndSwapLimit();
            t.hostTotalMemory = JVM.hostTotalMemory();
            t.commit();
        }
    }

    private static void emitContainerCPUUsage() {
        if (containerMetrics != null) {
            ContainerCPUUsageEvent event = new ContainerCPUUsageEvent();

            event.cpuTime = containerMetrics.getCpuUsage();
            event.cpuSystemTime = containerMetrics.getCpuSystemUsage();
            event.cpuUserTime = containerMetrics.getCpuUserUsage();
            event.commit();
        }
    }
    private static void emitContainerMemoryUsage() {
        if (containerMetrics != null) {
            ContainerMemoryUsageEvent event = new ContainerMemoryUsageEvent();

Configuration enabled period
profiling true 30 s
default true 30 s

Field Type Description
cpuTime long: nanos CPU Time Aggregate time consumed by all tasks in the container
cpuUserTime long: nanos CPU User Time Aggregate user time consumed by all tasks in the container
cpuSystemTime long: nanos CPU System Time Aggregate system time consumed by all tasks in the container

ContainerIOUsage

profiling default startTime duration stackTrace 17 21 25 26 27

Source src/jdk.jfr/share/classes/jdk/jfr/events/ContainerIOUsageEvent.java

Category: Operating System / File System

Container IO usage related information

Code Context

The event is likely defined and utilized in the following locations within the OpenJDK source code, which is licensed under the GPLv2, excluding any XML or configuration files:

src/jdk.jfr/share/classes/jdk/jfr/events/ContainerIOUsageEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "ContainerIOUsage")
@Label("Container IO Usage")
@Category({"Operating System", "File System"})
@Description("Container IO usage related information")
public class ContainerIOUsageEvent extends AbstractPeriodicEvent {

  @Label("Block IO Request Count")
  @Description("Number of block IO requests to the disk that have been issued by the container")
  public long serviceRequests;

  @Label("Block IO Transfer")
  @Description("Number of block IO bytes that have been transferred to/from the disk by the container")
  @DataAmount
  public long dataTransferred;
}

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

        if (JVM.isContainerized() ) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "JVM is containerized");
            containerMetrics = Container.metrics();
            if (containerMetrics != null) {
                Logger.log(LogTag.JFR_SYSTEM, LogLevel.DEBUG, "Container metrics are available");
            }
        }
        // The registration of events and hooks are needed to provide metadata,
        // even when not running in a container
        SecuritySupport.registerEvent(ContainerConfigurationEvent.class);
        SecuritySupport.registerEvent(ContainerCPUUsageEvent.class);
        SecuritySupport.registerEvent(ContainerCPUThrottlingEvent.class);
        SecuritySupport.registerEvent(ContainerMemoryUsageEvent.class);
        SecuritySupport.registerEvent(ContainerIOUsageEvent.class);

        PeriodicEvents.addJDKEvent(ContainerConfigurationEvent.class, emitContainerConfiguration);
        PeriodicEvents.addJDKEvent(ContainerCPUUsageEvent.class, emitContainerCPUUsage);
        PeriodicEvents.addJDKEvent(ContainerCPUThrottlingEvent.class, emitContainerCPUThrottling);
        PeriodicEvents.addJDKEvent(ContainerMemoryUsageEvent.class, emitContainerMemoryUsage);
        PeriodicEvents.addJDKEvent(ContainerIOUsageEvent.class, emitContainerIOUsage);
    }

    private static void emitExceptionStatistics() {
        ThrowableTracer.emitStatistics();
    }

    private static void emitContainerConfiguration() {
        if (containerMetrics != null) {
            ContainerConfigurationEvent t = new ContainerConfigurationEvent();
            t.containerType = containerMetrics.getProvider();
            t.cpuSlicePeriod = containerMetrics.getCpuPeriod();

src/jdk.jfr/share/classes/jdk/jfr/internal/instrument/JDKEvents.java:

    private static void emitContainerMemoryUsage() {
        if (containerMetrics != null) {
            ContainerMemoryUsageEvent event = new ContainerMemoryUsageEvent();

            event.memoryFailCount = containerMetrics.getMemoryFailCount();
            event.memoryUsage = containerMetrics.getMemoryUsage();
            event.swapMemoryUsage = containerMetrics.getMemoryAndSwapUsage();
            event.commit();
        }
    }

    private static void emitContainerIOUsage() {
        if (containerMetrics != null) {
            ContainerIOUsageEvent event = new ContainerIOUsageEvent();

            event.serviceRequests = containerMetrics.getBlkIOServiceCount();
            event.dataTransferred = containerMetrics.getBlkIOServiced();
            event.commit();
        }
    }

    private static void emitContainerCPUThrottling() {
        if (containerMetrics != null) {
            ContainerCPUThrottlingEvent event = new ContainerCPUThrottlingEvent();

Configuration enabled period
profiling true 30 s
default true 30 s

Field Type Description
serviceRequests long Block IO Request Count Number of block IO requests to the disk that have been issued by the container
dataTransferred long: bytes Block IO Transfer Number of block IO bytes that have been transferred to/from the disk by the container

Truffle Compiler

graal.compiler.truffle.CompilerStatistics

startTime duration every 1s graal vm only

Category: Truffle Compiler

Truffe Compiler Statistics

Field Type Description
compiledMethods ulong Compiled Methods Compiled Methods
bailouts ulong Bailouts Bailouts
invalidations ulong Invalidated Compilations Invalidated Compilations
compiledCodeSize ulong: bytes Compilation Resulting Size Compilation Resulting Size
totalTime long: millis Total Time Total Time
peakTime long: millis Peak Time Peak Time

graal.compiler.truffle.CompilationFailure

startTime duration graal vm only

Category: Truffle Compiler

Truffe Compilation Failures

Field Type Description
source string Source Compiled Source
language string Language Guest Language
rootFunction string Root Function Root Function
permanentFailure boolean Permanent Failure Permanent Failure
failureReason string Failure Reason Failure Reason

graal.compiler.truffle.Deoptimization

startTime duration graal vm only

Category: Truffle Compiler

Truffle Call Target Deoptimization

Field Type Description
source string Source Compiled Source
language string Language Guest Language
rootFunction string Root Function Root Function

graal.compiler.truffle.AssumptionInvalidation

startTime duration stackTrace graal vm only

Category: Truffle Compiler

Truffle Assumption Invalidation

Field Type Description
source string Source Compiled Source
language string Language Guest Language
rootFunction string Root Function Root Function
reason string Reason Invalidation Reason

graal.compiler.truffle.Compilation

startTime duration graal vm only

Category: Truffle Compiler

Truffe Compilation

Field Type Description
source string Source Compiled Source
language string Language Guest Language
rootFunction string Root Function Root Function
success boolean Succeeded Compilation Status
compiledCodeSize uint: bytes Compiled Code Size Compiled Code Size
compiledCodeAddress long Compiled Code Address Compiled Code Address
inlinedCalls uint Inlined Calls Inlined Calls
dispatchedCalls uint Dispatched Calls Dispatched Calls
graalNodeCount uint Graal Nodes Graal Node Count
peNodeCount uint Truffle Nodes Truffle Node Count
peTime ulong Partial Evaluation Time Partial Evaluation Time in Milliseconds

Types

Bytecode

14+

Bytecode Instruction

Field Type Description
bytecode string Instruction

Examples 3
ifne
invokeinterface
if_icmplt

CalleeMethod

Field Type Description
type string Class
name string Method Name
descriptor string Method Descriptor

Examples 3
descriptor string
(Lscala/Function1;)Lscala/Option;
name string
map
type string
scala/Option
descriptor string
(Lscala/collection/Iterator;Lscala/Function0;)V
name string
<init>
type string
org/apache/spark/util/CompletionIterator$$anon$1
descriptor string
(I)Ljava/lang/StringBuilder;
name string
append
type string
java/lang/StringBuilder

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 'non-profiled nmethods'
CodeHeap 'profiled nmethods'
CodeHeap 'non-profiled nmethods'

CompilerPhaseType

Compiler Phase Type

Field Type Description
phase string Phase

CompilerType

14+

Compiler Type

Field Type Description
compiler string Compiler

Examples 3
c2
c1
c1

CopyFailed

Field Type Description
objectCount ulong Object Count
firstSize ulong: bytes First Failed Object Size
smallestSize ulong: bytes Smallest Failed Object Size
totalSize ulong: bytes Total Object Size

DeoptimizationAction

14+

Deoptimization Action

Field Type Description
action string Action

Examples 3
reinterpret
maybe_recompile
maybe_recompile

DeoptimizationReason

14+

Deoptimization Reason

Field Type Description
reason string Reason

Examples 3
unstable_if
loop_limit_check
bimorphic_or_optimized_type_check

FlagValueOrigin

Flag Value Origin

Field Type Description
origin string Origin

Examples 3
Default
Default
Default

FrameType

Frame type

Field Type Description
description string Description

Examples 3
JIT compiled
JIT compiled
Inlined

G1EvacuationStatistics

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Field Type Description
gcId uint GC Identifier
allocated ulong: bytes Allocated Total memory allocated by PLABs
wasted ulong: bytes Wasted Total memory wasted within PLABs due to alignment or refill
used ulong: bytes Used Total memory occupied by objects within PLABs
undoWaste ulong: bytes Undo Wasted Total memory wasted due to allocation undo within PLABs
regionEndWaste ulong: bytes Region End Wasted Total memory wasted at the end of regions due to refill
regionsRefilled uint Region Refills Number of regions refilled
numPlabsFilled ulong 17+ PLAB Fills Number of PLABs filled
directAllocated ulong: bytes Allocated (direct) Total memory allocated using direct allocation outside of PLABs
numDirectAllocated ulong 17+ Direct allocations Number of direct allocations
failureUsed ulong: bytes Used (failure) Total memory occupied by objects in regions where evacuation failed
failureWaste ulong: bytes Wasted (failure) Total memory left unused in regions where evacuation failed

Examples 2
allocated ulong: bytes
1447160
directAllocated ulong: bytes
157840
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
935
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
1
undoWaste ulong: bytes
0
used ulong: bytes
1360536
wasted ulong: bytes
2352
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
1023
numDirectAllocated ulong
0
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
0
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0

G1HeapRegionType

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

G1 Heap Region Type

Field Type Description
type string Type

Examples 2
Continues Humongous
Free

G1YCType

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

G1 YC Type

Field Type Description
type string Type

Examples 1
Concurrent Start

GCCause

GC Cause

Field Type Description
cause string Cause

Examples 3
Heap Inspection Initiated GC
Heap Inspection Initiated GC
G1 Humongous Allocation

GCName

GC Name

Field Type Description
name string Name

Examples 3
G1Old
ParallelScavenge
G1New

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
After GC
Before GC
Before GC

InflateCause

Inflation Cause

Field Type Description
cause string Cause

MetadataType

Metadata Type

Field Type Description
type string Type

Examples 3
Metadata
Class
Metadata

MetaspaceObjectType

Metaspace Object Type

Field Type Description
type string Type

MetaspaceSizes

Field Type Description
committed ulong: bytes Committed Committed memory for this space
used ulong: bytes Used Bytes allocated by objects in the space
reserved ulong: bytes Reserved Reserved memory for this space

Examples 3
committed ulong: bytes
88276992
reserved ulong: bytes
1073741824
used ulong: bytes
86378200
committed ulong: bytes
571146240
reserved ulong: bytes
603979776
used ulong: bytes
569233368
committed ulong: bytes
659423232
reserved ulong: bytes
1677721600
used ulong: bytes
655611568

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

NMTType

21+

Native Memory Tracking Type

Field Type Description
name string Name

NarrowOopMode

Narrow Oop Mode

Field Type Description
mode string Mode

Examples 3
Zero based
Zero based
Zero based

NetworkInterfaceName

Network Interface

Field Type Description
networkInterface string Network Interface Network Interface Name

Examples 3
enP36980s1
eth0
eth0

ObjectSpace

Appearing in: ParallelGC

Missing in: G1GC, SerialGC, ShenandoahGC, ZGC

Field Type Description
start ulong: address Start Address Start address of the space
end ulong: address End Address End address of the space
used ulong: bytes Used Bytes allocated by objects in the space
size ulong: bytes Size Size of the space

Examples 3
end ulong: address
34010038272
size ulong: bytes
38797312
start ulong: address
33971240960
used ulong: bytes
37437632
end ulong: address
31730958336
size ulong: bytes
1565523968
start ulong: address
30165434368
used ulong: bytes
202719288
end ulong: address
33925103616
size ulong: bytes
963117056
start ulong: address
32961986560
used ulong: bytes
963117056

OldObject

Appearing in: G1GC, ParallelGC, SerialGC, ZGC

Missing in: ShenandoahGC

Old Object

Field Type Description
address ulong: address Memory Address
type Class Java Class
description string Object Description Object description
referrer Reference Referrer Object Object referencing this object

Examples 3
address ulong: address
31813036704
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
31018090648
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
hidden boolean
false
modifiers int
1
name string
io/netty/util/concurrent/DefaultPromise
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/util/concurrent
address ulong: address
30412826536
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[Ljava/util/concurrent/ForkJoinTask;
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/util/concurrent

OldObjectArray

Old Object Array

Field Type Description
size int Array Size Size of array
index int Index Index in the array

OldObjectField

Old Object Field

Field Type Description
name string Field Name of field
modifiers short Field Modifiers Field modifiers

OldObjectGcRoot

Appearing in: G1GC, ParallelGC, SerialGC, ZGC

Missing in: ShenandoahGC

GC Root

Field Type Description
description string Root Description Root information
system OldObjectRootSystem System The subsystem of origin for the root
type OldObjectRootType Type The root type

Examples 3
null
null
null

OldObjectRootSystem

GC Root System

Field Type Description
system string System

OldObjectRootType

GC Root Type

Field Type Description
type string Type

Package

Package

Field Type Description
name Symbol Name
module Module Module
exported boolean Exported

Reference

Appearing in: G1GC, ParallelGC, SerialGC, ZGC

Missing in: ShenandoahGC

Reference

Field Type Description
array OldObjectArray Array Information Array or null if it is not an array
field OldObjectField Field Information Field or null if it is an array
object OldObject Object Object holder for this reference
skip int Skip Value The object is this many hops away

Examples 3
null
null
null

ReferenceType

Reference Type

Field Type Description
type string Type

Examples 3
Final reference
Soft reference
Phantom reference

ShenandoahHeapRegionState

Appearing in: ShenandoahGC

Missing in: G1GC, ParallelGC, SerialGC, ZGC

Shenandoah Heap Region State

Field Type Description
state string State

Examples 2
Empty Uncommitted
Regular

StackFrame

Field Type Description
method Method Java Method
lineNumber int Line Number
bytecodeIndex int Bytecode Index
type FrameType Frame Type

Examples 3
bytecodeIndex int
5
lineNumber int
474
method Method
descriptor string
(Ljdk/internal/event/ThreadSleepEvent;)V
hidden boolean
false
modifiers int
10
name string
afterSleep
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Thread
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Inlined
bytecodeIndex int
304
lineNumber int
1436
method Method
descriptor string
(Ljava/lang/Class;I)V
hidden boolean
false
modifiers int
2
name string
filterCheck
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/ObjectInputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/io
type FrameType
JIT compiled
bytecodeIndex int
62
lineNumber int
375
method Method
descriptor string
(Ljava/lang/String;Ljava/lang/Throwable;ZZ)V
hidden boolean
false
modifiers int
4
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Throwable
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
JIT compiled

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-004314-16904521565326391942/apache-spark/lib/netty-buffer-4.1.99.Final.jar
file:///home/runner/work/jfrevents/jfrevents/harness-004314-6346519699961129921/twitter-finagle/lib/netty-buffer-4.1.99.Final.jar
file:///home/runner/work/jfrevents/jfrevents/harness-004327-18431318799373161124/apache-spark/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
virtual boolean 19+ Virtual Thread

ThreadGroup

Thread Group

Field Type Description
parent ThreadGroup Parent
name string Name

Examples 3
null
name string
system
parent ThreadGroup
null
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null

ThreadState

Java Thread State

Field Type Description
name string Name

Examples 3
STATE_RUNNABLE
STATE_RUNNABLE
STATE_RUNNABLE

VMOperationType

VM Operation Type

Field Type Description
type string Type

Examples 3
G1TryInitiateConcMark
JFRSafepointWrite
GC_HeapInspection

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
31730958336
committedSize ulong: bytes
1565523968
reservedEnd ulong: address
32961986560
reservedSize ulong: bytes
2796552192
start ulong: address
30165434368
committedEnd ulong: address
31138512896
committedSize ulong: bytes
973078528
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4194304000
start ulong: address
30165434368
committedEnd ulong: address
32787922944
committedSize ulong: bytes
2622488576
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4194304000
start ulong: address
30165434368

ZPageTypeType

15+

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Z Page Type

Field Type Description
type string Type

Examples 2
Small
Large

ZStatisticsCounterType

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Z Statistics Counter

Field Type Description
counter string Counter

Examples 1
Page Cache Hit L1

ZStatisticsSamplerType

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Z Statistics Sampler

Field Type Description
sampler string Sampler

Examples 1
Concurrent Mark Free

XML Content Types

address

Annotation: jdk.jfr.MemoryAddress

Examples 3
30165434368
30318662192
32193380352

bits-per-second

Annotation: jdk.jfr.DataAmount(BITS), jdk.jfr.Frequency

Examples 3
4912
37640
7280

bytes

Annotation: jdk.jfr.DataAmount(BYTES)

Examples 3
0
16
524208

bytes-per-second

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Annotation: jdk.jfr.DataAmount(BYTES), jdk.jfr.Frequency

Examples 2
2.0795261666761062E8
0.0

certificateId

Annotation: jdk.jfr.events.CertificateId

Examples 3
3045411335
3045411335
3045411335

epochmillis

Annotation: jdk.jfr.Timestamp(MILLISECONDS_SINCE_EPOCH)

Examples 3
1771720994247
1771720993806
-9223372036854775808

hertz

Annotation: jdk.jfr.Frequency

Examples 3
1000000000
2961.711
1000000000

microseconds

17+

Annotation: jdk.jfr.Timespan(MICROSECONDS)

millis

Annotation: jdk.jfr.Timespan(MILLISECONDS)

Examples 3
295244746371
298894876158
295202057674

nanos

Annotation: jdk.jfr.Timespan(NANOSECONDS)

Examples 3
0
10000000
99999920

percentage

Annotation: jdk.jfr.Percentage

Examples 3
0.025
0.3925
0.42

tickspan

Annotation: jdk.jfr.Timespan(TICKS)

Examples 3
0
570422417
2183860

tickstamp

Annotation: jdk.jfr.Timestamp(TICKS)

XML Types

Class

Parameter Type const Klass*
Field Type const Klass*
Java Type java.lang.Class
Examples 3
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[F
package Package
null
null
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;Ljava/lang/Throwable;ZZ)V
hidden boolean
false
modifiers int
4
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Throwable
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
descriptor string
(Ljdk/internal/event/ThreadSleepEvent;)V
hidden boolean
false
modifiers int
10
name string
afterSleep
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Thread
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
descriptor string
(Ljava/lang/Class;I)V
hidden boolean
false
modifiers int
2
name string
filterCheck
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/ObjectInputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/io

Module

Parameter Type const ModuleEntry*
Field Type const ModuleEntry*
Examples 3
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1

Package

Parameter Type const PackageEntry*
Field Type const PackageEntry*
Examples 3
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/net
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/io
null

StackTrace

15+

Parameter Type u8
Field Type u8
Java Type jdk.types.StackTrace
Examples 3
frames StackFrame
bytecodeIndex int
5
lineNumber int
474
method Method
descriptor string
(Ljdk/internal/event/ThreadSleepEvent;)V
hidden boolean
false
modifiers int
10
name string
afterSleep
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Thread
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
Inlined
truncated boolean
false
frames StackFrame
bytecodeIndex int
304
lineNumber int
1436
method Method
descriptor string
(Ljava/lang/Class;I)V
hidden boolean
false
modifiers int
2
name string
filterCheck
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/io/ObjectInputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/io
type FrameType
JIT compiled
truncated boolean
true
frames StackFrame
bytecodeIndex int
62
lineNumber int
375
method Method
descriptor string
(Ljava/lang/String;Ljava/lang/Throwable;ZZ)V
hidden boolean
false
modifiers int
4
name string
<init>
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Throwable
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.10.0.1
name string
java/lang
type FrameType
JIT compiled
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
block-manager-storage-async-thread-pool-65
javaThreadId long
1273
osName string
block-manager-storage-async-thread-pool-65
osThreadId long
3923
virtual boolean
false
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-storage-async-thread-pool-42
javaThreadId long
1304
osName string
block-manager-storage-async-thread-pool-42
osThreadId long
3960
virtual boolean
false
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-storage-async-thread-pool-63
javaThreadId long
1271
osName string
block-manager-storage-async-thread-pool-63
osThreadId long
3921
virtual boolean
false

Ticks

unsigned

Appearing in: G1GC, ParallelGC, SerialGC, ZGC

Missing in: ShenandoahGC

Parameter Type const Ticks&
Field Type Ticks
Java Type long
Content Type tickstamp
Examples 3
389045465405
509318823370
462124890239

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
true
false
false

byte

Parameter Type s1
Field Type s1
Java Type byte

char

Parameter Type char
Field Type char
Java Type char

double

Parameter Type double
Field Type double
Java Type double
Examples 3
20.0
1.0
25.0

float

Parameter Type float
Field Type float
Java Type float
Examples 3
2.1463
4.6066046
4.5954895

int

Parameter Type s4
Field Type s4
Java Type int
Examples 3
10
1
1041

long

Parameter Type s8
Field Type s8
Java Type long
Examples 3
3
528
26103

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
null
bootstrap
[F

ubyte

unsigned

Parameter Type u1
Field Type u1
Java Type byte
Examples 3
7
32
15

uint

unsigned

Parameter Type unsigned
Field Type unsigned
Java Type int
Examples 3
967
932
934

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