Introduction

The following are the events for OpenJDK 24 (jdk-24+21, permalink, 30-October-2024), and Graal VM 24.2.0 (jdk-24+21) . 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

default profiling startTime 11 17 21 23 24

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
default true
profiling true

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

DataLoss

default profiling startTime 11 17 21 23 24 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_swap_memory(JNIEnv* env, jclass jvm))
#ifdef LINUX
  // We want the host swap memory, not the container value.
  return os::Linux::host_swap();
#else
  return os::total_swap_space();
#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

NO_TRANSITION(jlong, jfr_nanos_now(JNIEnv* env, jclass jvm))

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
default true
profiling true

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

Flush

experimental startTime duration 14 17 21 23 24

Category: Flight Recorder

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

class StackTraceRepository : public StackObj {
 private:

Configuration enabled threshold
default false 0 ns
profiling false 0 ns

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

Examples 3
elements ulong
7987
flushId ulong
687
size ulong: bytes
1347356
startTime long: millis
902927740375
elements ulong
3301
flushId ulong
61
size ulong: bytes
655013
startTime long: millis
68221526208
elements ulong
2341
flushId ulong
38
size ulong: bytes
436031
startTime long: millis
40431316167

ActiveRecording

default profiling startTime duration stackTrace 11 17 21 23 24

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

Category: Flight Recorder

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined 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")
@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/JDKEvents.java:

public final class JDKEvents {

    private static final Class<?>[] eventClasses = {
        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.FileForceEvent.class,
        jdk.internal.event.FileReadEvent.class,
        jdk.internal.event.FileWriteEvent.class,
        jdk.internal.event.ProcessStartEvent.class,
        jdk.internal.event.SecurityPropertyModificationEvent.class,

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()
                    );

Configuration enabled
default true
profiling true

Field Type Description
id long Id
name string Name Consider contributing a description to jfreventcollector.
destination string Destination Consider contributing a description to jfreventcollector.
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
[...]/code/experiments/jfreventcollector/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
1702899981921
stackTrace StackTrace
null
startTime long: millis
75960656375
destination string
[...]/code/experiments/jfreventcollector/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
1727266203142
startTime long: millis
914255486833
destination string
[...]/code/experiments/jfreventcollector/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
1702899886817
stackTrace StackTrace
null
startTime long: millis
60342722167

ActiveSetting

default profiling startTime duration stackTrace 11 17 21 23 24

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

Category: Flight Recorder

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

package jdk.jfr.events;

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

@Name(Type.EVENT_NAME_PREFIX + "ActiveSetting")
@Label("Recording Setting")
@Category("Flight Recorder")
@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/JDKEvents.java:

public final class JDKEvents {

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

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/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;

Configuration enabled
default true
profiling true

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

Examples 3
id long
49
name string
threshold
startTime long: millis
791746993083
value string
0 ms
id long
45
name string
threshold
stackTrace StackTrace
null
startTime long: millis
416785542
value string
0 ms
id long
7
name string
period
stackTrace StackTrace
null
startTime long: millis
360834042
value string
1000 ms

JVM

JVMInformation

default profiling startTime duration end of every chunk 11 17 21 23 24 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
default true beginChunk
profiling true beginChunk

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

Examples 3
javaArguments string
[...]/code/experiments/jfreventcollector/.cache/renaissance.jar -t 5 -r 1 all
jvmArguments string
-XX:StartFlightRecording=filename=[...]/code/experiments/jfreventcollector/jfr/sample_UseParallelGC.jfr,settings=[...]/code/experiments/jfreventcollector/.cache/jfc.jfc -XX:+UseParallelGC
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1702899886436
jvmVersion string
OpenJDK 64-Bit Server VM (21.0.1+12-LTS) for bsd-aarch64 JRE (21.0.1+12-LTS), built on 2023-10-17T00:00:00Z by "admin" with clang Apple LLVM 12.0.0 (clang-1200.0.32.29)
pid long
13981
startTime long: millis
78940150083
javaArguments string
[...]/code/experiments/jfreventcollector/.cache/renaissance.jar -t 5 -r 1 all
jvmArguments string
-XX:StartFlightRecording=filename=[...]/code/experiments/jfreventcollector/jfr/sample_UseG1GC.jfr,settings=[...]/code/experiments/jfreventcollector/.cache/jfc.jfc -XX:+UseG1GC
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1727266202802
jvmVersion string
OpenJDK 64-Bit Server VM (22+36) for bsd-aarch64 JRE (22+36), built on 2024-03-13T13:18:01Z by "sapmachine" with clang Apple LLVM 13.0.0 (clang-1300.0.29.3)
pid long
26284
startTime long: millis
914271586292
javaArguments string
[...]/code/experiments/jfreventcollector/.cache/renaissance.jar -t 5 -r 1 all
jvmArguments string
-XX:StartFlightRecording=filename=[...]/code/experiments/jfreventcollector/jfr/sample_UseSerialGC.jfr,settings=[...]/code/experiments/jfreventcollector/.cache/jfc.jfc -XX:+UseSerialGC
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1702899981604
jvmVersion string
OpenJDK 64-Bit Server VM (21.0.1+12-LTS) for bsd-aarch64 JRE (21.0.1+12-LTS), built on 2023-10-17T00:00:00Z by "admin" with clang Apple LLVM 12.0.0 (clang-1200.0.32.29)
pid long
14273
startTime long: millis
84413939583

InitialSystemProperty

default profiling startTime end of every chunk 11 17 21 23 24 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
default true beginChunk
profiling true beginChunk

Field Type Description
key string Key
value string Value

Examples 3
key string
java.vm.specification.vendor
startTime long: millis
422632500
value string
Oracle Corporation
key string
java.vm.specification.vendor
startTime long: millis
842464969167
value string
Oracle Corporation
key string
java.vm.version
startTime long: millis
52080831625
value string
21.0.1+12-LTS

JVM: Class Loading

ClassLoad

startTime duration eventThread stackTrace 11 17 21 23 24

Category: Java Virtual Machine / Class Loading

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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/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()) {

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;"
  DEBUG_ONLY(ResourceMark rm(THREAD));
  assert(name != nullptr && !Signature::is_array(name) &&
         !Signature::has_envelope(name), "invalid class name: %s", name == nullptr ? "nullptr" : name->as_C_string());

  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");

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

Field Type Description
loadedClass Class Loaded Class Consider contributing a description to jfreventcollector.
definingClassLoader ClassLoader Defining Class Loader Consider contributing a description to jfreventcollector.
initiatingClassLoader ClassLoader Initiating Class Loader Consider contributing a description to jfreventcollector.

Examples 3
definingClassLoader ClassLoader
name string
bootstrap
type Class
null
initiatingClassLoader ClassLoader
name string
bootstrap
type Class
null
loadedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
32
name string
java/util/Collections$SynchronizedCollection
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
2407
method Method
descriptor string
(Ljava/util/Set;Ljava/lang/Object;)Ljava/util/Set;
hidden boolean
false
modifiers int
8
name string
synchronizedSet
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/util/Collections
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
378631375
definingClassLoader ClassLoader
name string
bootstrap
type Class
null
initiatingClassLoader ClassLoader
name string
bootstrap
type Class
null
loadedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
32
name string
java/util/Collections$SynchronizedSet
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
2407
method Method
descriptor string
(Ljava/util/Set;Ljava/lang/Object;)Ljava/util/Set;
hidden boolean
false
modifiers int
8
name string
synchronizedSet
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/util/Collections
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
436992042
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
22
name string
java/net
initiatingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/net
loadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/net
hidden boolean
false
modifiers int
1537
name string
scala/reflect/runtime/ThreadLocalStorage
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
22
name string
java/net
location string
null
name string
null
version string
null
name string
scala/reflect/runtime
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
22
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
843465551250

ClassDefine

startTime eventThread stackTrace 11 17 21 23 24

Category: Java Virtual Machine / Class Loading

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

Field Type Description
definedClass Class Defined Class Consider contributing a description to jfreventcollector.
definingClassLoader ClassLoader Defining Class Loader Consider contributing a description to jfreventcollector.

Examples 3
definedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1537
name string
sun/util/locale/provider/AvailableLanguageTags
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
sun/util/locale/provider
definingClassLoader ClassLoader
name string
bootstrap
type Class
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
221
method Method
descriptor string
()Ljava/text/spi/DecimalFormatSymbolsProvider;
hidden boolean
false
modifiers int
4098
name string
lambda$getDecimalFormatSymbolsProvider$4
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
sun/util/locale/provider/JRELocaleProviderAdapter
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
sun/util/locale/provider
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
402625708
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
22
name string
java/net
hidden boolean
false
modifiers int
17
name string
org/apache/spark/sql/SQLImplicits$$typecreator1$5
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
22
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
22
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
22
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
843437812125
definedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/text/DecimalFormatSymbols
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/text
definingClassLoader ClassLoader
name string
bootstrap
type Class
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
22
lineNumber int
2032
method Method
descriptor string
(Ljava/util/Locale;)Ljava/text/DecimalFormatSymbols;
hidden boolean
false
modifiers int
10
name string
getDecimalFormatSymbols
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
49
name string
java/util/Formatter
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
461199042

ClassRedefinition

default profiling startTime 15 17 21 23 24

Category: Java Virtual Machine / Class Loading

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true
profiling true

Field Type Description
redefinedClass Class Redefined Class Consider contributing a description to jfreventcollector.
classModificationCount int Class Modification Count The number of times the class has changed
redefinitionId ulong Class Redefinition Id

RedefineClasses

default profiling startTime duration eventThread stackTrace 15 17 21 23 24

Category: Java Virtual Machine / Class Loading

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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


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

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

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

RetransformClasses

default profiling startTime duration eventThread stackTrace 15 17 21 23 24

Category: Java Virtual Machine / Class Loading

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

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

ClassUnload

startTime eventThread 11 17 21 23 24

Category: Java Virtual Machine / Class Loading

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default false
profiling false

Field Type Description
unloadedClass Class Unloaded Class Consider contributing a description to jfreventcollector.
definingClassLoader ClassLoader Defining Class Loader Consider contributing a description to jfreventcollector.

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
22
name string
java/net
startTime long: millis
852482771417
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
22
name string
java/net
hidden boolean
false
modifiers int
25
name string
scala/collection/mutable/ArraySeq$ofByte
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
22
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection/mutable
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
startTime long: millis
3889491000
unloadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hidden boolean
false
modifiers int
1056
name string
org/sparkproject/guava/collect/AbstractMapEntry
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
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/sparkproject/guava/collect
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
startTime long: millis
4558815292
unloadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hidden boolean
false
modifiers int
48
name string
org/sparkproject/guava/collect/Maps$9
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
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
org/sparkproject/guava/collect

JVM: Code Cache

CodeCacheFull

default profiling startTime eventThread 11 17 21 23 24

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
default true
profiling true

Field Type Description
codeBlobType CodeBlobType Code Heap Consider contributing a description to jfreventcollector.
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

default profiling startTime every chunk 11 17 21 23 24

Category: Java Virtual Machine / Code Cache

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

Examples 3
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'profiled nmethods'
entryCount int
6766
fullCount int
0
methodCount int
6766
reservedTopAddress ulong: address
4668653568
startAddress ulong: address
4545757184
startTime long: millis
798681830958
unallocatedCapacity ulong: bytes
103619584
adaptorCount int
359
codeBlobType CodeBlobType
CodeHeap 'non-nmethods'
entryCount int
449
fullCount int
0
methodCount int
0
reservedTopAddress ulong: address
5094801408
startAddress ulong: address
5088952320
startTime long: millis
423297625
unallocatedCapacity ulong: bytes
4571136
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'profiled nmethods'
entryCount int
3759
fullCount int
0
methodCount int
3759
reservedTopAddress ulong: address
4604248064
startAddress ulong: address
4481351680
startTime long: millis
87695871083
unallocatedCapacity ulong: bytes
113593856

CodeCacheConfiguration

default profiling startTime end of every chunk 11 17 21 23 24

Category: Java Virtual Machine / Code Cache

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

Configuration enabled period
default true beginChunk
profiling true beginChunk

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

Examples 3
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
5839564
nonProfiledSize ulong: bytes
122909338
profiledSize ulong: bytes
122909338
reservedSize ulong: bytes
251658240
reservedTopAddress ulong: address
5217714176
startAddress ulong: address
4966055936
startTime long: millis
30586818958
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
5839564
nonProfiledSize ulong: bytes
122909338
profiledSize ulong: bytes
122909338
reservedSize ulong: bytes
251658240
reservedTopAddress ulong: address
4797415424
startAddress ulong: address
4545757184
startTime long: millis
833251964000
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
5839564
nonProfiledSize ulong: bytes
122909338
profiledSize ulong: bytes
122909338
reservedSize ulong: bytes
251658240
reservedTopAddress ulong: address
4733009920
startAddress ulong: address
4481351680
startTime long: millis
364792917

JVM: Compiler

JITRestart

default profiling startTime eventThread 17 21 23 24

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
default true
profiling true

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

Compilation

default profiling startTime duration eventThread 11 17 21 23 24

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/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, size_t arenaBytes) 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;

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(),
                                        task->arena_bytes());
}

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.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, size_t arenaBytes) {
  event.set_compileId(compile_id);
  event.set_compiler(compiler_type);
  event.set_method(method);
  event.set_compileLevel((short)compile_level);
  event.set_succeded(success);
  event.set_isOsr(is_osr);
  event.set_codeSize(code_size);
  event.set_inlinedBytes(inlined_bytecodes);
  event.set_arenaBytes(arenaBytes);

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

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

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

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

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

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

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

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

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

        void setCompileId(int compileId);

        void setCompileLevel(int compileLevel);

        void setSucceeded(boolean succeeded);

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

package jdk.vm.ci.hotspot;

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

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

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

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

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

Configuration enabled threshold
default true 1000 ms
profiling true 100 ms

Field Type Description
compileId int Compilation Identifier
compiler CompilerType 14+ Compiler Consider contributing a description to jfreventcollector.
method Method Method Consider contributing a description to jfreventcollector.
compileLevel ushort Compilation Level
succeded boolean Succeeded
isOsr boolean On Stack Replacement
codeSize ulong: bytes Compiled Code Size
inlinedBytes ulong: bytes Inlined Code Size
arenaBytes ulong: bytes 23+ Arena Usage

Examples 3
codeSize ulong: bytes
36728
compileId int
110185
compileLevel ushort
4
compiler CompilerType
c2
inlinedBytes ulong: bytes
4485
isOsr boolean
false
method Method
descriptor string
(Ldotty/tools/dotc/core/Names$Name;Ldotty/tools/dotc/core/Types$Type;JJLdotty/tools/dotc/core/Contexts$Context;Ldotty/tools/dotc/core/Types$Type;)Ldotty/tools/dotc/core/Denotations$Denotation;
hidden boolean
false
modifiers int
18
name string
go$1
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/net
hidden boolean
false
modifiers int
1033
name string
dotty/tools/dotc/core/Types$Type
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
22
name string
java/net
location string
null
name string
null
version string
null
name string
dotty/tools/dotc/core
startTime long: millis
912204325458
succeded boolean
true
codeSize ulong: bytes
36688
compileId int
16822
compileLevel ushort
4
compiler CompilerType
c2
inlinedBytes ulong: bytes
7319
isOsr boolean
false
method Method
descriptor string
(Lio/reactors/ReactorSystem;Ljava/lang/Throwable;)V
hidden boolean
false
modifiers int
1
name string
postschedule
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hidden boolean
false
modifiers int
33
name string
io/reactors/JvmScheduler$ReactorForkJoinWorkerThread
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
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/reactors
startTime long: millis
46091483875
succeded boolean
true
codeSize ulong: bytes
3536
compileId int
8398
compileLevel ushort
4
compiler CompilerType
c2
inlinedBytes ulong: bytes
500
isOsr boolean
false
method Method
descriptor string
()I
hidden boolean
false
modifiers int
1
name string
deleteMax
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hidden boolean
false
modifiers int
33
name string
cafesat/common/FixedIntDoublePriorityQueue
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
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
cafesat/common
startTime long: millis
30200636417
succeded boolean
true

CompilerPhase

default profiling startTime duration eventThread 11 17 21 23 24

Category: Java Virtual Machine / Compiler

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

Code Context

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

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

    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_internal()) { return; } // failing_internal to not stress bailouts from printing code.
  EventCompilerPhase event(UNTIMED);
  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));
  int iter = ++_igv_phase_iter[cpt];
  if (iter > 1) {
    ss.print(" %d", iter);
  }

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(UNTIMED);
  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_isOsr(is_osr);
  event.set_codeSize(code_size);
  event.set_inlinedBytes(inlined_bytecodes);
  event.set_arenaBytes(arenaBytes);
  commit(event);
}

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

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

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

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

C2V_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(UNTIMED);
  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/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
default true 60 s
profiling true 10 s

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

CompilationFailure

profiling startTime eventThread 11 17 21 23 24

Category: Java Virtual Machine / Compiler

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

Code Context

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

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

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

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

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

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

    int inlined_bytecodes, size_t arenaBytes) {
  event.set_compileId(compile_id);
  event.set_compiler(compiler_type);
  event.set_method(method);
  event.set_compileLevel((short)compile_level);
  event.set_succeded(success);
  event.set_isOsr(is_osr);
  event.set_codeSize(code_size);
  event.set_inlinedBytes(inlined_bytecodes);
  event.set_arenaBytes(arenaBytes);
  commit(event);
}

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

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

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

// ------------------------------------------------------------------
// ciEnv::record_failure()
void ciEnv::record_failure(const char* reason) {
  if (_failure_reason.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) {

Configuration enabled
default false
profiling true

Field Type Description
failureMessage string Failure Message
compileId int Compilation Identifier

Examples 3
compileId int
22930
failureMessage string
concurrent class loading
startTime long: millis
74091028458
compileId int
23245
failureMessage string
concurrent class loading
startTime long: millis
82998780708
compileId int
99696
failureMessage string
concurrent class loading
startTime long: millis
890105317542

CompilerInlining

startTime eventThread 11 17 21 23 24

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/compiler/compilerEvent.hpp:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

C2V_VMENTRY(void, notifyCompilerPhaseEvent, (JNIEnv* env, jobject, jlong startTime, jint phase, jint compileId, jint level))
  EventCompilerPhase event(UNTIMED);
  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/c1/c1_GraphBuilder.cpp:

  append(new MemBar(lir_membar_storestore));
}

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/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
default false
profiling 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
1
callee CalleeMethod
descriptor string
()Lorg/apache/spark/util/LongAccumulator;
name string
_executorCpuTime
type string
org/apache/spark/executor/TaskMetrics
caller Method
descriptor string
()J
hidden boolean
false
modifiers int
1
name string
executorCpuTime
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
22
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/spark/executor/TaskMetrics
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
22
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/executor
compileId int
85781
message string
inline
startTime long: millis
791931772083
succeeded boolean
true
bci int
94
callee CalleeMethod
descriptor string
(B)V
name string
putUncheckedByte
type string
jdk/jfr/internal/event/EventWriter
caller Method
descriptor string
(J)V
hidden boolean
false
modifiers int
2
name string
putUncheckedLong
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
49
name string
jdk/jfr/internal/event/EventWriter
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.jfr
name string
jdk.jfr
version string
21.0.1
name string
jdk/jfr/internal/event
compileId int
1446
message string
callee uses too much stack
startTime long: millis
361734250
succeeded boolean
false
bci int
2
callee CalleeMethod
descriptor string
(I)Ljava/lang/AbstractStringBuilder;
name string
append
type string
java/lang/AbstractStringBuilder
caller Method
descriptor string
(I)Ljava/lang/StringBuilder;
hidden boolean
false
modifiers int
1
name string
append
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
49
name string
java/lang/StringBuilder
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/lang
compileId int
1448
message string
callee is too large
startTime long: millis
415542875
succeeded boolean
false

Deoptimization

default profiling startTime eventThread stackTrace 14 17 21 23 24

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(nmethod* 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
default true false
profiling true true

Field Type Description
compileId int Compilation Identifier
compiler CompilerType Compiler Consider contributing a description to jfreventcollector.
method Method Method Consider contributing a description to jfreventcollector.
lineNumber int Line Number
bci int Bytecode Index
instruction Bytecode Instruction Consider contributing a description to jfreventcollector.
reason DeoptimizationReason Reason Consider contributing a description to jfreventcollector.
action DeoptimizationAction Action Consider contributing a description to jfreventcollector.

Examples 3
action DeoptimizationAction
maybe_recompile
bci int
12
compileId int
2640
compiler CompilerType
c2
instruction Bytecode
invokevirtual
lineNumber int
3743
method Method
descriptor string
(Ljava/util/regex/Pattern$TreeInfo;)Z
hidden boolean
false
modifiers int
0
name string
study
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
32
name string
java/util/regex/Pattern$Node
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util/regex
reason DeoptimizationReason
class_check
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
12
lineNumber int
3743
method Method
descriptor string
(Ljava/util/regex/Pattern$TreeInfo;)Z
hidden boolean
false
modifiers int
0
name string
study
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
32
name string
java/util/regex/Pattern$Node
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util/regex
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
4167293792
action DeoptimizationAction
reinterpret
bci int
7
compileId int
88645
compiler CompilerType
c2
instruction Bytecode
ifeq
lineNumber int
82
method Method
descriptor string
(J)Z
hidden boolean
false
modifiers int
1
name string
pendingWakeups
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
22
name string
java/net
hidden boolean
false
modifiers int
17
name string
scala/concurrent/stm/ccstm/CCSTM$
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
22
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
7
lineNumber int
82
method Method
descriptor string
(J)Z
hidden boolean
false
modifiers int
1
name string
pendingWakeups
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
22
name string
java/net
hidden boolean
false
modifiers int
17
name string
scala/concurrent/stm/ccstm/CCSTM$
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
22
name string
java/net
location string
null
name string
null
version string
null
name string
scala/concurrent/stm/ccstm
type FrameType
Inlined
truncated boolean
false
startTime long: millis
853034560750
action DeoptimizationAction
reinterpret
bci int
10
compileId int
2621
compiler CompilerType
c2
instruction Bytecode
ifeq
lineNumber int
751
method Method
descriptor string
(Ljava/util/Spliterator;)I
hidden boolean
false
modifiers int
8
name string
fromCharacteristics
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
16432
name string
java/util/stream/StreamOpFlag
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util/stream
reason DeoptimizationReason
unstable_if
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
10
lineNumber int
751
method Method
descriptor string
(Ljava/util/Spliterator;)I
hidden boolean
false
modifiers int
8
name string
fromCharacteristics
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
16432
name string
java/util/stream/StreamOpFlag
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util/stream
type FrameType
Inlined
truncated boolean
false
startTime long: millis
2043598542

CompilerQueueUtilization

default profiling startTime duration every chunk 22 23 24

Category: Java Virtual Machine / Compiler

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true 10 s
profiling true 5 s

Field Type Description
compiler CompilerType Compiler Consider contributing a description to jfreventcollector.
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

Examples 1
addedCount long
200
addedRate long: hertz
10
compiler CompilerType
c1
compilerThreadCount int
1
peakQueueSize long
206
queueSize long
0
removedCount long
200
removedRate long: hertz
10
startTime long: millis
817603746792
totalAddedCount long
64419
totalRemovedCount long
64419

CompilerStatistics

default profiling startTime every chunk 11 17 21 23 24

Category: Java Virtual Machine / Compiler

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true 1000 ms
profiling true 1000 ms

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

Examples 3
bailoutCount int
3
compileCount int
19149
invalidatedCount int
0
nmethodCodeSize ulong: bytes
23129880
nmethodsSize ulong: bytes
36106760
osrBytesCompiled ulong: bytes
0
osrCompileCount int
195
peakTimeSpent long: millis
953
standardBytesCompiled ulong: bytes
0
standardCompileCount int
18954
startTime long: millis
66530844292
totalTimeSpent long: millis
47870
bailoutCount int
3
compileCount int
31243
invalidatedCount int
0
nmethodCodeSize ulong: bytes
39667208
nmethodsSize ulong: bytes
61096056
osrBytesCompiled ulong: bytes
0
osrCompileCount int
216
peakTimeSpent long: millis
1360
standardBytesCompiled ulong: bytes
0
standardCompileCount int
31027
startTime long: millis
88354715250
totalTimeSpent long: millis
73879
bailoutCount int
10
compileCount int
82910
invalidatedCount int
0
nmethodCodeSize ulong: bytes
109251776
nmethodsSize ulong: bytes
165193688
osrBytesCompiled ulong: bytes
0
osrCompileCount int
969
peakTimeSpent long: millis
10885
standardBytesCompiled ulong: bytes
0
standardCompileCount int
81941
startTime long: millis
851133905542
totalTimeSpent long: millis
384556

CompilerConfiguration

default profiling startTime end of every chunk 11 17 21 23 24

Category: Java Virtual Machine / Compiler

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true beginChunk
profiling 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
842485375458
threadCount int
4
tieredCompilation boolean
true
dynamicCompilerThreadCount boolean
true
startTime long: millis
423294458
threadCount int
4
tieredCompilation boolean
true
dynamicCompilerThreadCount boolean
true
startTime long: millis
84416222667
threadCount int
4
tieredCompilation boolean
true

JVM: Diagnostics

SyncOnValueBasedClass

experimental default profiling startTime eventThread stackTrace 16 17 21 23 24

Category: Java Virtual Machine / Diagnostics

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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;
    Log(valuebasedclasses) vblog;

    vblog.info("Synchronizing on object " INTPTR_FORMAT " of klass %s", p2i(obj()), obj->klass()->external_name());
    if (locking_thread->has_last_Java_frame()) {
      LogStream info_stream(vblog.info());
      locking_thread->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
default true true
profiling true true

Field Type Description
valueBasedClass Class Value Based Class Consider contributing a description to jfreventcollector.

HeapDump

default profiling startTime duration eventThread stackTrace 15 17 21 23 24

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:

  if (_oome && num_dump_threads > 1) {
    // Each additional parallel writer requires several MB of internal memory
    // (DumpWriter buffer, DumperClassCacheTable, GZipCompressor buffers).
    // For the OOM handling we may already be limited in memory.
    // Lets ensure we have at least 20MB per thread.
    julong max_threads = os::free_memory() / (20 * M);
    if (num_dump_threads > max_threads) {
      num_dump_threads = MAX2<uint>(1, (uint)max_threads);
    }
  }

  // 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
default true true 0 ns
profiling 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

default profiling startTime end of every chunk 21 23 24

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
default true endChunk
profiling 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

default profiling startTime end of every chunk 21 23 24

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
default true endChunk
profiling 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

default profiling startTime 11 17 21 23 24

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

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

Configuration enabled
default true
profiling true

Field Type Description
name string Name
oldValue int Old Value
newValue int New Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

UnsignedIntFlagChanged

default profiling startTime 11 17 21 23 24

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

Configuration enabled
default true
profiling true

Field Type Description
name string Name
oldValue uint Old Value
newValue uint New Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

LongFlagChanged

default profiling startTime 11 17 21 23 24

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

Configuration enabled
default true
profiling true

Field Type Description
name string Name
oldValue long Old Value
newValue long New Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

UnsignedLongFlagChanged

default profiling startTime 11 17 21 23 24

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

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

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

Configuration enabled
default true
profiling true

Field Type Description
name string Name
oldValue ulong Old Value
newValue ulong New Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

DoubleFlagChanged

default profiling startTime 11 17 21 23 24

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

Configuration enabled
default true
profiling true

Field Type Description
name string Name
oldValue double Old Value
newValue double New Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

BooleanFlagChanged

default profiling startTime 11 17 21 23 24

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

    return JVMFlag::SUCCESS;
  }

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

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

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

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

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

Configuration enabled
default true
profiling true

Field Type Description
name string Name
oldValue boolean Old Value
newValue boolean New Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

StringFlagChanged

default profiling startTime 11 17 21 23 24

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true
profiling true

Field Type Description
name string Name
oldValue string Old Value
newValue string New Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

IntFlag

default profiling startTime duration end of every chunk 11 17 21 23 24

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
name string Name
value int Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

Examples 3
name string
JavaPriority1_To_OSPriority
origin FlagValueOrigin
Default
startTime long: millis
39268374542
value int
-1
name string
StackPrintLimit
origin FlagValueOrigin
Default
startTime long: millis
805718650625
value int
100
name string
ParGCArrayScanChunk
origin FlagValueOrigin
Default
startTime long: millis
40031149792
value int
50

UnsignedIntFlag

default profiling startTime duration end of every chunk 11 17 21 23 24

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
name string Name
value uint Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

Examples 3
name string
TestCrashInErrorHandler
origin FlagValueOrigin
Default
startTime long: millis
805718657625
value uint
0
name string
VerifyIterativeGVN
origin FlagValueOrigin
Default
startTime long: millis
39268377083
value uint
0
name string
G1RemSetArrayOfCardsEntriesBase
origin FlagValueOrigin
Default
startTime long: millis
30519915125
value uint
8

LongFlag

default profiling startTime duration end of every chunk 11 17 21 23 24

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
name string Name
value long Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

Examples 3
name string
CIStop
origin FlagValueOrigin
Default
startTime long: millis
423472750
value long
2147483647
name string
Tier2BackedgeNotifyFreqLog
origin FlagValueOrigin
Default
startTime long: millis
364810750
value long
14
name string
Tier3BackedgeNotifyFreqLog
origin FlagValueOrigin
Default
startTime long: millis
791773047375
value long
13

UnsignedLongFlag

default profiling startTime duration end of every chunk 11 17 21 23 24

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
name string Name
value ulong Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

Examples 3
name string
CodeCacheExpansionSize
origin FlagValueOrigin
Default
startTime long: millis
791773058458
value ulong
65536
name string
CompressedClassSpaceSize
origin FlagValueOrigin
Default
startTime long: millis
423586042
value ulong
1073741824
name string
NUMAPageScanRate
origin FlagValueOrigin
Default
startTime long: millis
364820042
value ulong
256

DoubleFlag

default profiling startTime duration end of every chunk 11 17 21 23 24

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
name string Name
value double Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

Examples 3
name string
CompileThresholdScaling
origin FlagValueOrigin
Default
startTime long: millis
423590875
value double
1.0
name string
ZAllocationSpikeTolerance
origin FlagValueOrigin
Default
startTime long: millis
15845390083
value double
2.0
name string
ZFragmentationLimit
origin FlagValueOrigin
Default
startTime long: millis
791773070250
value double
0.0

BooleanFlag

default profiling startTime duration end of every chunk 11 17 21 23 24

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
name string Name
value boolean Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

Examples 3
name string
AssertRangeCheckElimination
origin FlagValueOrigin
Default
startTime long: millis
423597833
value boolean
false
name string
EliminateBlocks
origin FlagValueOrigin
Default
startTime long: millis
791773074792
value boolean
true
name string
UseCompressedOops
origin FlagValueOrigin
Ergonomic
startTime long: millis
364836292
value boolean
true

StringFlag

default profiling startTime duration end of every chunk 11 17 21 23 24

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
name string Name
value string Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

Examples 3
name string
StartFlightRecording
origin FlagValueOrigin
Command line
startTime long: millis
805718891583
value string
filename=[...]/code/experiments/jfreventcollector/jfr/sample_UseG1GC.jfr,settings=[...]/code/experiments/jfreventcollector/.cache/jfc.jfc
name string
ShenandoahGCMode
origin FlagValueOrigin
Default
startTime long: millis
364881167
value string
satb
name string
DeoptimizeOnlyAt
origin FlagValueOrigin
Default
startTime long: millis
17899930458
value string

JVM: GC: Collector

GarbageCollection

default profiling startTime duration eventThread 11 17 21 23 24 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
default true 0 ms
profiling true 0 ms

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

Examples 3
cause GCCause
G1 Evacuation Pause
gcId uint
916
longestPause Tickspan
3350416
name GCName
G1New
startTime long: millis
854442733292
sumOfPauses Tickspan
3350416
cause GCCause
Allocation Failure
gcId uint
67
longestPause Tickspan
78378084
name GCName
DefNew
startTime long: millis
8232473833
sumOfPauses Tickspan
78378084
cause GCCause
Allocation Failure
gcId uint
31
longestPause Tickspan
85214708
name GCName
ParallelScavenge
startTime long: millis
18795478417
sumOfPauses Tickspan
85214708

SystemGC

default profiling startTime duration eventThread stackTrace 17 21 23 24 graal vm

Category: Java Virtual Machine / GC / Collector

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true true 0 ms
profiling true true 0 ms

Field Type Description
invokedConcurrent boolean Invoked Concurrent

Examples 3
invokedConcurrent boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
257
name string
gc
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
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
21.0.1
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
45189866000
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
33
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
21.0.1
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
38514425792
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
22
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
852435396125

ParallelOldGarbageCollection

default profiling startTime duration 11 17 21 23 24

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
default true 0 ms
profiling true 0 ms

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

Examples 1
densePrefix ulong: address
30160715776
gcId uint
92
startTime long: millis
64383837083

YoungGarbageCollection

default profiling startTime duration 11 17 21 23 24

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
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
tenuringThreshold uint Tenuring Threshold

Examples 3
gcId uint
83
startTime long: millis
12832219667
tenuringThreshold uint
1
gcId uint
980
startTime long: millis
909315560667
tenuringThreshold uint
15
gcId uint
58
startTime long: millis
38452683542
tenuringThreshold uint
15

OldGarbageCollection

default profiling startTime duration 11 17 21 23 24

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
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier

Examples 3
gcId uint
60
startTime long: millis
39039436375
gcId uint
924
startTime long: millis
871529937917
gcId uint
69
startTime long: millis
8416182875

G1GarbageCollection

default profiling startTime duration 11 17 21 23 24

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
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
type G1YCType Type Consider contributing a description to jfreventcollector.

Examples 1
gcId uint
904
startTime long: millis
846688164000
type G1YCType
Concurrent Start

ZYoungGarbageCollection

default profiling startTime duration eventThread 21 23 24

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
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
tenuringThreshold uint Tenuring Threshold

ZOldGarbageCollection

default profiling startTime duration eventThread 21 23 24

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
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier

JVM: GC: Configuration

GCConfiguration

default profiling startTime duration end of every chunk 11 17 21 23 24

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
default true everyChunk
profiling true everyChunk

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

Examples 3
concurrentGCThreads uint
0
gcTimeRatio uint
99
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
SerialOld
parallelGCThreads uint
0
pauseTarget long: millis
-9223372036854775808
startTime long: millis
87968008833
usesDynamicGCThreads boolean
true
youngCollector GCName
DefNew
concurrentGCThreads uint
0
gcTimeRatio uint
99
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
ParallelOld
parallelGCThreads uint
8
pauseTarget long: millis
-9223372036854775808
startTime long: millis
39156311500
usesDynamicGCThreads boolean
true
youngCollector GCName
ParallelScavenge
concurrentGCThreads uint
2
gcTimeRatio uint
12
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
G1Old
parallelGCThreads uint
8
pauseTarget long: millis
-9223372036854775808
startTime long: millis
914473073667
usesDynamicGCThreads boolean
true
youngCollector GCName
G1New

GCSurvivorConfiguration

default profiling startTime duration end of every chunk 11 17 21 23 24

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
default true beginChunk
profiling true beginChunk

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

Examples 3
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
805885237958
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
76136277167
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
75222449417

GCTLABConfiguration

default profiling startTime duration end of every chunk 11 17 21 23 24

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
default true beginChunk
profiling true beginChunk

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

Examples 3
minTLABSize ulong: bytes
2048
startTime long: millis
18250636333
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
minTLABSize ulong: bytes
2048
startTime long: millis
791929054625
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
minTLABSize ulong: bytes
2048
startTime long: millis
30690533708
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true

GCHeapConfiguration

default profiling startTime duration end of every chunk 11 17 21 23 24

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
default true beginChunk
profiling true beginChunk

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

Examples 3
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
268435456
maxSize ulong: bytes
4294967296
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
39413198875
usesCompressedOops boolean
true
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
268435456
maxSize ulong: bytes
4294967296
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
871662545375
usesCompressedOops boolean
true
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
268435456
maxSize ulong: bytes
4294967296
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
88354589583
usesCompressedOops boolean
true

YoungGenerationConfiguration

default profiling startTime duration end of every chunk 11 17 21 23 24

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
default true beginChunk
profiling true beginChunk

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

Examples 3
maxSize ulong: bytes
1431633920
minSize ulong: bytes
89456640
newRatio uint
2
startTime long: millis
30690535375
maxSize ulong: bytes
2575302656
minSize ulong: bytes
1363144
newRatio uint
2
startTime long: millis
857590629958
maxSize ulong: bytes
1431306240
minSize ulong: bytes
89128960
newRatio uint
2
startTime long: millis
436502958

JVM: GC: Detailed

ZThreadDebug

internal startTime duration eventThread 18 21 23 24

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.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());
}

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();
  }
}

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

G1MMU

default profiling startTime 11 17 21 23 24

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

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

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

Configuration enabled
default true
profiling true

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

Examples 1
gcId uint
896
gcTime long: millis
33
pauseTarget long: millis
200
startTime long: millis
840073382792
timeSlice long: millis
201

EvacuationInformation

default profiling startTime 11 17 21 23 24

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true
profiling true

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

Examples 1
allocationRegions uint
1
allocationRegionsUsedAfter ulong: bytes
1645488
allocationRegionsUsedBefore ulong: bytes
0
bytesCopied ulong: bytes
1645488
cSetRegions uint
11
cSetUsedAfter ulong: bytes
0
cSetUsedBefore ulong: bytes
21030152
gcId uint
901
regionsFreed uint
11
startTime long: millis
843406119792

ObjectCountAfterGC

startTime 11 17 21 23 24

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, ZGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default false
profiling false

Field Type Description
gcId uint GC Identifier
objectClass Class Object Class Consider contributing a description to jfreventcollector.
count long Count
totalSize ulong: bytes Total Size

Examples 3
count long
60440
gcId uint
69
objectClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hidden boolean
false
modifiers int
33
name string
akka/actor/ActorCell
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
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
akka/actor
startTime long: millis
8663866792
totalSize ulong: bytes
5318720
count long
129370
gcId uint
866
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
22
name string
java/lang
startTime long: millis
792378118375
totalSize ulong: bytes
2069920
count long
341
gcId uint
1
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
49
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
21.0.1
name string
java/lang/invoke
startTime long: millis
431274583
totalSize ulong: bytes
13640

G1EvacuationYoungStatistics

default profiling startTime 11 17 21 23 24

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
default true
profiling true

Field Type Description
statistics G1EvacuationStatistics struct Evacuation Statistics

Examples 1
startTime long: millis
846703996458
statistics G1EvacuationStatistics
allocated ulong: bytes
1630080
directAllocated ulong: bytes
16400
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
904
numDirectAllocated ulong
5
numPlabsFilled ulong
6652858312
regionEndWaste ulong: bytes
0
regionsRefilled uint
1
undoWaste ulong: bytes
0
used ulong: bytes
1425320
wasted ulong: bytes
6456

G1EvacuationOldStatistics

default profiling startTime 11 17 21 23 24

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
default true
profiling true

Field Type Description
statistics G1EvacuationStatistics struct Evacuation Statistics

Examples 1
startTime long: millis
854446022375
statistics G1EvacuationStatistics
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
916
numDirectAllocated ulong
6115354792
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
0
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0

G1BasicIHOP

default profiling startTime 11 17 21 23 24

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
default true
profiling true

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

Examples 1
currentOccupancy ulong: bytes
284283512
gcId uint
999
lastMarkingDuration long: millis
3397
recentAllocationRate double: bytes-per-second
0.0
recentMutatorAllocationSize ulong: bytes
0
recentMutatorDuration long: millis
1514
startTime long: millis
940332101250
targetOccupancy ulong: bytes
895483904
threshold ulong: bytes
10972078
thresholdPercentage float: percentage
0.01225268

G1AdaptiveIHOP

default profiling startTime 11 17 21 23 24

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
default true
profiling true

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

Examples 1
additionalBufferSize ulong: bytes
1509949440
currentOccupancy ulong: bytes
391457464
gcId uint
953
ihopTargetOccupancy ulong: bytes
2390753280
predictedAllocationRate double: bytes-per-second
1.3699919867794466E8
predictedMarkingDuration long: millis
3728
predictionActive boolean
true
startTime long: millis
884747014083
threshold ulong: bytes
369976249
thresholdPercentage float: percentage
0.154753

PromoteObjectInNewPLAB

profiling startTime eventThread 11 17 21 23 24

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
default false
profiling true

Field Type Description
gcId uint GC Identifier Identifier signifying GC during which the object was promoted
objectClass Class Object Class Class of promoted object
objectSize ulong: bytes Object Size Size of promoted object
tenuringAge uint Object Tenuring Age Tenuring age of a surviving object before being copied. The tenuring age of an object is a value between 0-15 and is incremented each 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
865
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
2064
startTime long: millis
792215746042
tenured boolean
false
tenuringAge uint
0
gcId uint
5
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
[B
package Package
null
objectSize ulong: bytes
24
plabSize ulong: bytes
8176
startTime long: millis
1164011125
tenured boolean
true
tenuringAge uint
1

PromoteObjectOutsidePLAB

profiling startTime eventThread 11 17 21 23 24

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
default false
profiling true

Field Type Description
gcId uint GC Identifier Identifier signifying GC during which the object was promoted
objectClass Class Object Class Class of promoted object
objectSize ulong: bytes Object Size Size of promoted object
tenuringAge uint Object Tenuring Age Tenuring age of a surviving object before being copied. The tenuring age of an object is a value between 0-15 and is incremented each 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
2
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
[B
package Package
null
objectSize ulong: bytes
51824
startTime long: millis
969292333
tenured boolean
false
tenuringAge uint
0
gcId uint
895
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
22
name string
java/io
objectSize ulong: bytes
5648
startTime long: millis
839859170708
tenured boolean
false
tenuringAge uint
0

PromotionFailed

default profiling startTime 11 17 21 23 24

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
default true
profiling true

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

EvacuationFailed

default profiling startTime 11 17 21 23 24

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
default true
profiling true

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

ConcurrentModeFailure

default profiling startTime 11 17 21 23 24

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
default true
profiling true

Field Type Description
gcId uint GC Identifier

Examples 1
gcId uint
899
startTime long: millis
842593416333

GCCPUTime

default profiling startTime 17 21 23 24

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
default true
profiling 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
66
realTime ulong: nanos
0
startTime long: millis
49108722792
systemTime ulong: nanos
0
userTime ulong: nanos
0
gcId uint
35
realTime ulong: nanos
0
startTime long: millis
2032856375
systemTime ulong: nanos
0
userTime ulong: nanos
9999999
gcId uint
922
realTime ulong: nanos
0
startTime long: millis
869730737083
systemTime ulong: nanos
0
userTime ulong: nanos
0

AllocationRequiringGC

startTime eventThread stackTrace 11 17 21 23 24 graal vm

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, ZGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

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

Configuration enabled stackTrace
default false true
profiling false true

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

Examples 3
gcId uint
969
size ulong: bytes
1048576
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
27
lineNumber int
177
method Method
descriptor string
(Ljava/util/stream/Collector;)Ljava/util/stream/TerminalOp;
hidden boolean
false
modifiers int
9
name string
makeRef
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
16
name string
java/util/stream/ReduceOps
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/util/stream
type FrameType
Inlined
truncated boolean
true
startTime long: millis
895818638292
gcId uint
74
size ulong: bytes
2064
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
133
lineNumber int
710
method Method
descriptor string
()[Ljava/util/HashMap$Node;
hidden boolean
false
modifiers int
16
name string
resize
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/util/HashMap
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
59401052208
gcId uint
68
size ulong: bytes
16
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
30
lineNumber int
201
method Method
descriptor string
(Lakka/actor/ActorSystemImpl;Lakka/actor/RepointableActorRef;Lakka/actor/Props;Lakka/actor/InternalActorRef;)V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hidden boolean
false
modifiers int
33
name string
akka/actor/UnstartedCell
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
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
akka/actor
type FrameType
Inlined
truncated boolean
false
startTime long: millis
8362537958

TenuringDistribution

default profiling startTime 11 17 21 23 24

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, SerialGC

Missing in: ParallelGC, ShenandoahGC, ZGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

Configuration enabled
default true
profiling true

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

Examples 2
age uint
1
gcId uint
873
size ulong: bytes
26984
startTime long: millis
802915843708
age uint
15
gcId uint
5
size ulong: bytes
0
startTime long: millis
1187180792

G1HeapRegionTypeChange

startTime 11 17 21 23 24

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/g1HeapRegionTracer.cpp:

void G1HeapRegionTracer::send_region_type_change(uint index,
                                               G1HeapRegionTraceType::Type from,
                                               G1HeapRegionTraceType::Type to,
                                               uintptr_t start,
                                               size_t used) {
  EventG1HeapRegionTypeChange e;
  if (e.should_commit()) {
    e.set_index(index);
    e.set_from(from);
    e.set_to(to);
    e.set_start(start);
    e.set_used(used);
    e.commit();
  }
}

Configuration enabled
default false
profiling false

Field Type Description
index uint Index
from G1HeapRegionType From Consider contributing a description to jfreventcollector.
to G1HeapRegionType To Consider contributing a description to jfreventcollector.
start ulong: address Start
used ulong: bytes Used

Examples 1
from G1HeapRegionType
Free
index uint
157
start ulong: address
30394023936
startTime long: millis
791919066167
to G1HeapRegionType
Free
used ulong: bytes
0

ObjectCount

startTime every chunk 11 17 21 23 24

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, ZGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

Field Type Description
gcId uint GC Identifier
objectClass Class Object Class Consider contributing a description to jfreventcollector.
count long Count
totalSize ulong: bytes Total Size

Examples 3
count long
1658
gcId uint
8
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
[Ljava/util/HashMap$Node;
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util
startTime long: millis
1360118500
totalSize ulong: bytes
2284072
count long
194342
gcId uint
22
objectClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hidden boolean
false
modifiers int
49
name string
akka/dispatch/sysmsg/DeathWatchNotification
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
akka/dispatch/sysmsg
startTime long: millis
9266401125
totalSize ulong: bytes
4664208
count long
3649
gcId uint
872
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1040
name string
[Ljava/util/concurrent/ConcurrentHashMap$Node;
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/util/concurrent
startTime long: millis
800281069667
totalSize ulong: bytes
28055784

G1HeapRegionInformation

startTime duration every chunk 11 17 21 23 24

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 G1HeapRegionClosure {
public:
  bool do_heap_region(G1HeapRegion* 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
default false everyChunk
profiling false everyChunk

Field Type Description
index uint Index
type G1HeapRegionType Type Consider contributing a description to jfreventcollector.
start ulong: address Start
used ulong: bytes Used

Examples 1
index uint
88
start ulong: address
30249320448
startTime long: millis
791928945542
type G1HeapRegionType
Old
used ulong: bytes
1629040

ZAllocationStall

default profiling startTime duration eventThread stackTrace 15 17 21 23 24

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 stackTrace threshold
default true true 17+ 0 ms
profiling true true 17+ 0 ms

Field Type Description
type ZPageTypeType Type Consider contributing a description to jfreventcollector.
size ulong: bytes Size

Examples 1
size ulong: bytes
2097152
startTime long: millis
12626236958
type ZPageTypeType
Small

ZPageAllocation

default profiling startTime duration eventThread stackTrace 11 17 21 23 24

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
default true true 15+ 1 ms
profiling true true 15+ 1 ms

Field Type Description
type ZPageTypeType 15+ Type Consider contributing a description to jfreventcollector.
size ulong: bytes 15+ Size
flushed ulong: bytes 15+ Flushed
committed ulong: bytes 15+ Committed
segments uint 15+ Segments
nonBlocking boolean Non-blocking

Examples 1
committed ulong: bytes
2097152
flushed ulong: bytes
0
nonBlocking boolean
false
segments uint
1
size ulong: bytes
2097152
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
114
lineNumber int
156
method Method
descriptor string
(Lscala/collection/IterableOnce;)Lscala/collection/immutable/List;
hidden boolean
false
modifiers int
1
name string
prependedAll
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hidden boolean
false
modifiers int
1057
name string
scala/collection/immutable/List
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
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection/immutable
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
11642285333
type ZPageTypeType
Small

ZRelocationSet

default profiling startTime duration eventThread 15 17 21 23 24

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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/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 {

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 {

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

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

Examples 1
empty ulong: bytes
2464153600
relocate ulong: bytes
3496024
startTime long: millis
66245131458
total ulong: bytes
2787115008

ZRelocationSetGroup

default profiling startTime duration eventThread 15 17 21 23 24

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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/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),

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);
    }
  }

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
type ZPageTypeType Type Consider contributing a description to jfreventcollector.
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
2
empty ulong: bytes
6291456
relocate ulong: bytes
0
selectedPages ulong
0
startTime long: millis
1112214500
total ulong: bytes
14680064
type ZPageTypeType
Large

ZStatisticsCounter

experimental startTime duration eventThread 11 17 21 23 24

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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.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) {

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;

Configuration enabled threshold
default false 0 ms
profiling false 0 ms

Field Type Description
id ZStatisticsCounterType Id Consider contributing a description to jfreventcollector.
increment ulong Increment
value ulong Value

Examples 1
id ZStatisticsCounterType
Page Cache Hit L3
increment ulong
1
startTime long: millis
756457291
value ulong
19

ZStatisticsSampler

experimental startTime duration eventThread 11 17 21 23 24

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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.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) {

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);

Configuration enabled threshold
default false 0 ms
profiling false 0 ms

Field Type Description
id ZStatisticsSamplerType Id Consider contributing a description to jfreventcollector.
value ulong Value

Examples 1
id ZStatisticsSamplerType
Concurrent Weak Roots OopStorageSet
startTime long: millis
751977916
value ulong
104167

ZThreadPhase

experimental startTime duration eventThread 11 17 21 23 24

Category: Java Virtual Machine / GC / Detailed

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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.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) :

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;

Configuration enabled threshold
default false 0 ms
profiling false 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 1
gcId uint
4
name string
Concurrent Mark Try Flush
startTime long: millis
1995255500

ZUncommit

default profiling startTime duration eventThread 15 17 21 23 24

Category: Java Virtual Machine / GC / Detailed

Uncommitting of memory

Code Context

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

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

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

void ZUncommitter::run_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;

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;

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
uncommitted ulong: bytes Uncommitted

ZUnmap

default profiling startTime duration eventThread 15 17 21 23 24

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/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) {

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) {

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
unmapped ulong: bytes Unmapped

Examples 1
startTime long: millis
17684273250
unmapped ulong: bytes
2097152

ShenandoahHeapRegionStateChange

startTime 11 17 21 23 24

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
default false
profiling false

Field Type Description
index uint Index
from ShenandoahHeapRegionState From Consider contributing a description to jfreventcollector.
to ShenandoahHeapRegionState To Consider contributing a description to jfreventcollector.
start ulong: address Start
used ulong: bytes Used

Examples 1
from ShenandoahHeapRegionState
Regular
index uint
6
start ulong: address
30077353984
startTime long: millis
805901542
to ShenandoahHeapRegionState
Collection Set
used ulong: bytes
2097152

ShenandoahHeapRegionInformation

startTime duration every chunk 11 17 21 23 24

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
default false everyChunk
profiling false everyChunk

Field Type Description
index uint Index
state ShenandoahHeapRegionState State Consider contributing a description to jfreventcollector.
start ulong: address Start
used ulong: bytes Used

Examples 1
index uint
11
start ulong: address
30087839744
startTime long: millis
363233542
state ShenandoahHeapRegionState
Regular
used ulong: bytes
2097152

GCLocker

default profiling startTime eventThread stackTrace 17 21 23 24

Category: Java Virtual Machine / GC / Detailed

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true true 1 s
profiling true true 100 ms

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

JVM: GC: Heap

GCHeapSummary

default profiling startTime 11 17 21 23 24 graal vm

Category: Java Virtual Machine / GC / Heap

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

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

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

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

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier
when GCWhen When Consider contributing a description to jfreventcollector.
heapSpace VirtualSpace struct Heap Space Consider contributing a description to jfreventcollector.
heapUsed ulong: bytes Heap Used Bytes allocated by objects in the heap

Examples 3
gcId uint
879
heapSpace VirtualSpace
committedEnd ulong: address
31086084096
committedSize ulong: bytes
1021313024
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4294967296
start ulong: address
30064771072
heapUsed ulong: bytes
439765288
startTime long: millis
810904214833
when GCWhen
Before GC
gcId uint
27
heapSpace VirtualSpace
committedEnd ulong: address
30324359168
committedSize ulong: bytes
259588096
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4294967296
start ulong: address
30064771072
heapUsed ulong: bytes
108132400
startTime long: millis
1927833792
when GCWhen
After GC
gcId uint
16
heapSpace VirtualSpace
committedEnd ulong: address
30968643584
committedSize ulong: bytes
903872512
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4294967296
start ulong: address
30064771072
heapUsed ulong: bytes
91897456
startTime long: millis
4601091042
when GCWhen
After GC

MetaspaceSummary

default profiling startTime 11 17 21 23 24

Category: Java Virtual Machine / GC / Heap

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

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

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier
when GCWhen When Consider contributing a description to jfreventcollector.
gcThreshold ulong: bytes GC Threshold
metaspace MetaspaceSizes struct Total Consider contributing a description to jfreventcollector.
dataSpace MetaspaceSizes struct Data Consider contributing a description to jfreventcollector.
classSpace MetaspaceSizes struct Class Consider contributing a description to jfreventcollector.

Examples 3
classSpace MetaspaceSizes
committed ulong: bytes
87490560
reserved ulong: bytes
1073741824
used ulong: bytes
86004336
dataSpace MetaspaceSizes
committed ulong: bytes
552992768
reserved ulong: bytes
603979776
used ulong: bytes
551276784
gcId uint
883
gcThreshold ulong: bytes
1067515904
metaspace MetaspaceSizes
committed ulong: bytes
640483328
reserved ulong: bytes
1677721600
used ulong: bytes
637281120
startTime long: millis
824395518417
when GCWhen
After GC
classSpace MetaspaceSizes
committed ulong: bytes
3080192
reserved ulong: bytes
1073741824
used ulong: bytes
2799096
dataSpace MetaspaceSizes
committed ulong: bytes
23265280
reserved ulong: bytes
67108864
used ulong: bytes
23160768
gcId uint
44
gcThreshold ulong: bytes
42860544
metaspace MetaspaceSizes
committed ulong: bytes
26345472
reserved ulong: bytes
1140850688
used ulong: bytes
25959864
startTime long: millis
4795756917
when GCWhen
Before GC
classSpace MetaspaceSizes
committed ulong: bytes
2490368
reserved ulong: bytes
1073741824
used ulong: bytes
2420392
dataSpace MetaspaceSizes
committed ulong: bytes
20512768
reserved ulong: bytes
67108864
used ulong: bytes
20385360
gcId uint
5
gcThreshold ulong: bytes
36700160
metaspace MetaspaceSizes
committed ulong: bytes
23003136
reserved ulong: bytes
1140850688
used ulong: bytes
22805752
startTime long: millis
1161052083
when GCWhen
Before GC

PSHeapSummary

default profiling startTime 11 17 21 23 24

Category: Java Virtual Machine / GC / Heap

Appearing in: ParallelGC

Missing in: G1GC, SerialGC, ShenandoahGC, ZGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

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

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

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier
when GCWhen When Consider contributing a description to jfreventcollector.
oldSpace VirtualSpace struct Old Space Consider contributing a description to jfreventcollector.
oldObjectSpace ObjectSpace struct Old Object Space Consider contributing a description to jfreventcollector.
youngSpace VirtualSpace struct Young Space Consider contributing a description to jfreventcollector.
edenSpace ObjectSpace struct Eden Space Consider contributing a description to jfreventcollector.
fromSpace ObjectSpace struct From Space Consider contributing a description to jfreventcollector.
toSpace ObjectSpace struct To Space Consider contributing a description to jfreventcollector.

Examples 1
edenSpace ObjectSpace
end ulong: address
33871101952
size ulong: bytes
942669824
start ulong: address
32928432128
used ulong: bytes
0
fromSpace ObjectSpace
end ulong: address
34359738368
size ulong: bytes
202375168
start ulong: address
34157363200
used ulong: bytes
144064608
gcId uint
35
oldObjectSpace ObjectSpace
end ulong: address
30407131136
size ulong: bytes
342360064
start ulong: address
30064771072
used ulong: bytes
274960072
oldSpace VirtualSpace
committedEnd ulong: address
30407131136
committedSize ulong: bytes
342360064
reservedEnd ulong: address
32928432128
reservedSize ulong: bytes
2863661056
start ulong: address
30064771072
startTime long: millis
21800381417
toSpace ObjectSpace
end ulong: address
34115420160
size ulong: bytes
244318208
start ulong: address
33871101952
used ulong: bytes
0
when GCWhen
After GC
youngSpace VirtualSpace
committedEnd ulong: address
34359738368
committedSize ulong: bytes
1431306240
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
1431306240
start ulong: address
32928432128

G1HeapSummary

default profiling startTime 11 17 21 23 24

Category: Java Virtual Machine / GC / Heap

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true
profiling true

Field Type Description
gcId uint GC Identifier
when GCWhen When Consider contributing a description to jfreventcollector.
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
545259520
edenUsedSize ulong: bytes
20971520
gcId uint
898
numberOfRegions uint
434
oldGenUsedSize ulong: bytes
256618680
startTime long: millis
842424691167
survivorUsedSize ulong: bytes
0
when GCWhen
Before GC

JVM: GC: Metaspace

MetaspaceGCThreshold

default profiling startTime 11 17 21 23 24

Category: Java Virtual Machine / GC / Metaspace

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

Configuration enabled
default true
profiling true

Field Type Description
oldValue ulong: bytes Old Value
newValue ulong: bytes New Value
updater GCThresholdUpdater Updater Consider contributing a description to jfreventcollector.

Examples 3
newValue ulong: bytes
1247739904
oldValue ulong: bytes
1245839360
startTime long: millis
873182723792
updater GCThresholdUpdater
compute_new_size
newValue ulong: bytes
38338560
oldValue ulong: bytes
36700160
startTime long: millis
1497583958
updater GCThresholdUpdater
compute_new_size
newValue ulong: bytes
140050432
oldValue ulong: bytes
138608640
startTime long: millis
52069724333
updater GCThresholdUpdater
compute_new_size

MetaspaceAllocationFailure

default profiling startTime stackTrace 11 17 21 23 24

Category: Java Virtual Machine / GC / Metaspace

Appearing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Missing in: G1GC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

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

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

Configuration enabled stackTrace
default true true
profiling true true

Field Type Description
classLoader ClassLoader Class Loader Consider contributing a description to jfreventcollector.
hiddenClassLoader boolean 15+ Hidden Class Loader
size ulong: bytes Size
metadataType MetadataType Metadata Type Consider contributing a description to jfreventcollector.
metaspaceObjectType MetaspaceObjectType Metaspace Object Type Consider contributing a description to jfreventcollector.

Examples 3
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hiddenClassLoader boolean
false
metadataType MetadataType
Metadata
metaspaceObjectType MetaspaceObjectType
Method
size ulong: bytes
88
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/String;[BIILjava/security/ProtectionDomain;Ljava/lang/String;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass1
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1057
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
21.0.1
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
858453667
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hiddenClassLoader boolean
false
metadataType MetadataType
Metadata
metaspaceObjectType MetaspaceObjectType
ConstMethod
size ulong: bytes
104
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
1057
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
21.0.1
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
817189417
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hiddenClassLoader boolean
false
metadataType MetadataType
Metadata
metaspaceObjectType MetaspaceObjectType
ConstantPool
size ulong: bytes
2440
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
1057
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
21.0.1
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
967526042

MetaspaceOOM

default profiling startTime stackTrace 11 17 21 23 24

Category: Java Virtual Machine / GC / Metaspace

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

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

Configuration enabled stackTrace
default true true
profiling true true

Field Type Description
classLoader ClassLoader Class Loader Consider contributing a description to jfreventcollector.
hiddenClassLoader boolean 15+ Hidden Class Loader
size ulong: bytes Size
metadataType MetadataType Metadata Type Consider contributing a description to jfreventcollector.
metaspaceObjectType MetaspaceObjectType Metaspace Object Type Consider contributing a description to jfreventcollector.

MetaspaceChunkFreeListSummary

default profiling startTime 11 17 21 23 24

Category: Java Virtual Machine / GC / Metaspace

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

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

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

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier
when GCWhen When Consider contributing a description to jfreventcollector.
metadataType MetadataType Metadata Type Consider contributing a description to jfreventcollector.
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
869
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
798809177208
when GCWhen
After GC
gcId uint
10
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
1762570542
when GCWhen
After GC
gcId uint
3
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
1087489708
when GCWhen
After GC

JVM: GC: Phases

GCPhasePause

default profiling startTime duration eventThread 11 17 21 23 24 graal vm

Category: Java Virtual Machine / GC / Phases

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
86
name string
GC Pause
startTime long: millis
13827072417
gcId uint
45
name string
GC Pause
startTime long: millis
27460490917
gcId uint
910
name string
GC Pause
startTime long: millis
849799673875

GCPhasePauseLevel1

default profiling startTime duration eventThread 11 17 21 23 24 graal vm

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Missing in: ZGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
875
name string
Notify PhantomReferences
startTime long: millis
808675904333
gcId uint
17
name string
Weak Processing
startTime long: millis
5544432500
gcId uint
24
name string
Notify Soft/WeakReferences
startTime long: millis
1888599958

GCPhasePauseLevel2

default profiling startTime duration eventThread 11 17 21 23 24 graal vm

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, ZGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
95
name string
Reference Processing
startTime long: millis
16230376542
gcId uint
872
name string
Purge Class Loader Data
startTime long: millis
800253094000
gcId uint
9
name string
Dense Prefix Task Setup
startTime long: millis
1444495417

GCPhasePauseLevel3

startTime duration eventThread 11 17 21 23 24 graal vm

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, ZGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default false 0 ms
profiling false 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
37
name string
Trigger cleanups
startTime long: millis
3891150042
gcId uint
874
name string
Notify Soft/WeakReferences
startTime long: millis
805788732792
gcId uint
9
name string
ClassLoaderData
startTime long: millis
1429261708

GCPhasePauseLevel4

startTime duration eventThread 11 17 21 23 24 graal vm

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ParallelGC

Missing in: SerialGC, ShenandoahGC, ZGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default false 0 ms
profiling false 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 2
gcId uint
879
name string
Balance queues
startTime long: millis
810946346417
gcId uint
71
name string
Balance queues
startTime long: millis
54597846208

GCPhaseConcurrent

default profiling startTime duration eventThread 11 17 21 23 24

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ShenandoahGC, ZGC

Missing in: ParallelGC, SerialGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

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

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

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:

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
5
name string
Concurrent Reset Relocation Set
startTime long: millis
2336060208
gcId uint
0
name string
Roots
startTime long: millis
806388000
gcId uint
891
name string
Concurrent Mark From Roots
startTime long: millis
839560765125

GCPhaseConcurrentLevel1

default profiling startTime duration eventThread 15 17 21 23 24

Category: Java Virtual Machine / GC / Phases

Appearing in: G1GC, ShenandoahGC, ZGC

Missing in: ParallelGC, SerialGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

Examples 3
gcId uint
26
name string
ClassLoaderData
startTime long: millis
38806322708
gcId uint
49
name string
Trigger cleanups
startTime long: millis
71924028333
gcId uint
996
name string
Preclean PhantomReferences
startTime long: millis
935763658875

GCPhaseConcurrentLevel2

default profiling startTime duration eventThread 21 23 24

Category: Java Virtual Machine / GC / Phases

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
name string Name

GCPhaseParallel

default profiling startTime duration eventThread 12 17 21 23 24

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/g1/g1YoungGCPostEvacuateTasks.cpp:

    _before_used_bytes += used;
    _regions_freed += 1;
  }

  void account_card_rs_length(G1HeapRegion* r) {
    _card_rs_length += r->rem_set()->occupied();
  }
};

// Closure applied to all regions in the collection set.
class FreeCSetClosure : public G1HeapRegionClosure {
  // Helper to send JFR events for regions.
  class JFREventForRegion {
    EventGCPhaseParallel _event;

  public:
    JFREventForRegion(G1HeapRegion* 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/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(G1HeapRegion* 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);
      G1ScanAndCountNMethodClosure cl(_pss->closures()->weak_nmethods());

      // 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/g1HeapRegionManager.cpp:

      _worker_freelists[worker].~G1FreeRegionList();
    }
    FREE_C_HEAP_ARRAY(G1FreeRegionList, _worker_freelists);
  }

  G1FreeRegionList* 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;
    }

    G1FreeRegionList* free_list = worker_freelist(worker_id);
    for (uint i = start; i < end; i++) {

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

#ifndef SHARE_GC_G1_G1GCPARPHASETIMESTRACKER_HPP
#define SHARE_GC_G1_G1GCPARPHASETIMESTRACKER_HPP

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

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

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

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

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

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

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

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

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

#endif // SHARE_GC_SHENANDOAH_SHENANDOAHPHASETIMINGS_HPP

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) {

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

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

Examples 2
gcId uint
865
gcWorkerId uint
4
name string
RedirtyCards
startTime long: millis
792225952625
gcId uint
3
gcWorkerId uint
2
name string
Update Region States
startTime long: millis
4564598792

JVM: GC: Reference

GCReferenceStatistics

default profiling startTime 11 17 21 23 24

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
default true
profiling true

Field Type Description
gcId uint GC Identifier
type ReferenceType Type Consider contributing a description to jfreventcollector.
count ulong Total Count

Examples 3
count ulong
452
gcId uint
879
startTime long: millis
810947954792
type ReferenceType
Final reference
count ulong
0
gcId uint
8
startTime long: millis
1360544208
type ReferenceType
Soft reference
count ulong
0
gcId uint
1
startTime long: millis
861512917
type ReferenceType
Soft reference

JVM: Heap

GCHeapMemoryUsage

default profiling startTime every chunk 21 23 24

Category: Java Virtual Machine / Heap

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true everyChunk
profiling 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
1852833792
max ulong: bytes
3817865216
startTime long: millis
74874892000
used ulong: bytes
241191600
committed ulong: bytes
973078528
max ulong: bytes
4294967296
startTime long: millis
795726495167
used ulong: bytes
434993720
committed ulong: bytes
471662592
max ulong: bytes
4151836672
startTime long: millis
84155356917
used ulong: bytes
142681576

GCHeapMemoryPoolUsage

default profiling startTime every chunk 21 23 24

Category: Java Virtual Machine / Heap

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true everyChunk
profiling 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
431030272
max ulong: bytes
2863333376
name string
Tenured Gen
startTime long: millis
39583546125
used ulong: bytes
89389008
committed ulong: bytes
708837376
max ulong: bytes
2863661056
name string
PS Old Gen
startTime long: millis
74874892000
used ulong: bytes
98390136
committed ulong: bytes
442499072
max ulong: bytes
4294967296
name string
G1 Old Gen
startTime long: millis
805691504000
used ulong: bytes
292067832

JVM: Internal

Duration

internal startTime duration eventThread 18 21 23 24

Category: Java Virtual Machine / Internal

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Instant

internal startTime eventThread 18 21 23 24

Category: Java Virtual Machine / Internal

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined 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 23 24

Category: Java Virtual Machine / Internal

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Field Type Description
value ulong Value

Text

internal startTime eventThread 18 21 23 24

Category: Java Virtual Machine / Internal

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Field Type Description
text string Text

JVM: Memory

ResidentSetSize

default profiling startTime duration every chunk 21 23 24

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/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;

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/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;
    }
  }

Configuration enabled period
default true 1000 ms
profiling 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
2008924160
size ulong: bytes
1620656128
startTime long: millis
62484732875
peak ulong: bytes
936050688
size ulong: bytes
579600384
startTime long: millis
53353705625
peak ulong: bytes
2562785280
size ulong: bytes
387039232
startTime long: millis
860629520708

NativeMemoryUsage

default profiling startTime duration every chunk 20 21 23 24 graal vm

Category: Java Virtual Machine / Memory

Native memory usage for a given memory tag 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, MemTag mem_tag, size_t reserved, size_t committed) {
  EventNativeMemoryUsage event(UNTIMED);
  event.set_starttime(starttime);
  event.set_type(NMTUtil::tag_to_index(mem_tag));
  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
default true 1000 ms
profiling 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

default profiling startTime duration every chunk 20 21 23 24 graal vm

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, MemTag mem_tag, size_t reserved, size_t committed) {
  EventNativeMemoryUsage event(UNTIMED);
  event.set_starttime(starttime);
  event.set_type(NMTUtil::tag_to_index(mem_tag));
  event.set_reserved(reserved);

Configuration enabled period
default true 1000 ms
profiling 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

NativeMemoryUsageTotalPeak

experimental startTime duration graal vm only

Category: Java Virtual Machine / Memory

Total native memory peak usage for the JVM (GraalVM Native Image only). Might not be the exact sum of the NativeMemoryUsagePeak events due to timing.

Field Type Description
peakReserved long: bytes Peak Reserved
peakCommitted long: bytes Peak Committed
countAtPeak long Count At Peak

NativeMemoryUsagePeak

experimental startTime duration graal vm only

Category: Java Virtual Machine / Memory

Native memory peak usage for a given memory type in the JVM (GraalVM Native Image only).

Field Type Description
type string Memory Type
peakReserved long: bytes Peak Reserved
peakCommitted long: bytes Peak Committed
countAtPeak long Count At Peak

JVM: Profiling

OldObjectSample

cutoff default profiling startTime eventThread stackTrace 11 17 21 23 24 graal vm

Category: Java Virtual Machine / Profiling

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/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

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();
    }
  }
};

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

Field Type Description
allocationTime Ticks Allocation Time Consider contributing a description to jfreventcollector.
objectSize ulong: bytes 18+ Object Size
objectAge Tickspan 14+ Object Age Consider contributing a description to jfreventcollector.
lastKnownHeapUsage ulong: bytes Last Known Heap Usage
object OldObject Object Consider contributing a description to jfreventcollector.
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 Consider contributing a description to jfreventcollector.

Examples 3
allocationTime Ticks
37575647500
arrayElements int
10447
lastKnownHeapUsage ulong: bytes
132764920
object OldObject
address ulong: address
31582952064
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
[B
package Package
null
objectAge Tickspan
61392350208
objectSize ulong: bytes
10464
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
128
lineNumber int
1678
method Method
descriptor string
(I)V
hidden boolean
false
modifiers int
2
name string
initCEN
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
32
name string
java/util/zip/ZipFile$Source
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util/zip
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
98967997708
allocationTime Ticks
93744217333
arrayElements int
-2147483648
lastKnownHeapUsage ulong: bytes
117658120
object OldObject
address ulong: address
30180937480
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
48
name string
java/util/concurrent/SynchronousQueue$TransferStack$SNode
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util/concurrent
objectAge Tickspan
322692917
objectSize ulong: bytes
32
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
4
lineNumber int
328
method Method
descriptor string
(Ljava/util/concurrent/SynchronousQueue$TransferStack$SNode;Ljava/lang/Object;Ljava/util/concurrent/SynchronousQueue$TransferStack$SNode;I)Ljava/util/concurrent/SynchronousQueue$TransferStack$SNode;
hidden boolean
false
modifiers int
8
name string
snode
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
48
name string
java/util/concurrent/SynchronousQueue$TransferStack
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util/concurrent
type FrameType
Inlined
truncated boolean
false
startTime long: millis
94066910250
allocationTime Ticks
890593730875
arrayElements int
57
lastKnownHeapUsage ulong: bytes
254588816
object OldObject
address ulong: address
30279696552
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
50271951542
objectSize ulong: bytes
80
root OldObjectGcRoot
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
59
lineNumber int
3852
method Method
descriptor string
([BII)[B
hidden boolean
false
modifiers int
9
name string
copyOfRange
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/util/Arrays
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/util
type FrameType
Inlined
truncated boolean
false
startTime long: millis
940865682417

ExecutionSample

default profiling startTime every chunk 11 17 21 23 24 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/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

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);

Configuration enabled period
default true 20 ms
profiling true 10 ms

Field Type Description
sampledThread Thread Thread Consider contributing a description to jfreventcollector.
stackTrace StackTrace Stack Trace Consider contributing a description to jfreventcollector.
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 3.0 in stage 22.0 (TID 158)
javaThreadId long
1677
osName string
Executor task launch worker for task 3.0 in stage 22.0 (TID 158)
osThreadId long
178003
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
120
lineNumber int
496
method Method
descriptor string
(I)Z
hidden boolean
false
modifiers int
2
name string
resize
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
22
name string
java/util
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
796150399042
state ThreadState
STATE_RUNNABLE
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
ForkJoinPool.commonPool-worker-1
javaThreadId long
23
osName string
ForkJoinPool.commonPool-worker-1
osThreadId long
31751
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
5
lineNumber int
54
method Method
descriptor string
(I)Ljava/lang/Object;
hidden boolean
false
modifiers int
1
name string
get
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hidden boolean
false
modifiers int
49
name string
io/jenetics/internal/collection/ObjectStore
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
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/jenetics/internal/collection
type FrameType
Inlined
truncated boolean
false
startTime long: millis
4511862500
state ThreadState
STATE_RUNNABLE
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
ForkJoinPool.commonPool-worker-2
javaThreadId long
32
osName string
ForkJoinPool.commonPool-worker-2
osThreadId long
27143
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
5
lineNumber int
54
method Method
descriptor string
(I)Ljava/lang/Object;
hidden boolean
false
modifiers int
1
name string
get
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hidden boolean
false
modifiers int
49
name string
io/jenetics/internal/collection/ObjectStore
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
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/jenetics/internal/collection
type FrameType
Inlined
truncated boolean
false
startTime long: millis
4753113667
state ThreadState
STATE_RUNNABLE

NativeMethodSample

default profiling startTime every chunk 11 17 21 23 24 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/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

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;

Configuration enabled period
default true 20 ms
profiling true 20 ms

Field Type Description
sampledThread Thread Thread Consider contributing a description to jfreventcollector.
stackTrace StackTrace Stack Trace Consider contributing a description to jfreventcollector.
state ThreadState Thread State

Examples 3
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
1
osName string
main
osThreadId long
8707
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
([BII)I
hidden boolean
false
modifiers int
258
name string
readBytes0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/io/RandomAccessFile
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/io
type FrameType
Native
truncated boolean
false
startTime long: millis
787061083
state ThreadState
STATE_RUNNABLE
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
1
osName string
main
osThreadId long
10499
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
([BII)I
hidden boolean
false
modifiers int
258
name string
readBytes0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/io/RandomAccessFile
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/io
type FrameType
Native
truncated boolean
false
startTime long: millis
2775126375
state ThreadState
STATE_RUNNABLE
sampledThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
SparkUI-1619
javaThreadId long
1619
osName string
SparkUI-1619
osThreadId long
172567
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(IJIJ)I
hidden boolean
false
modifiers int
264
name string
poll
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
sun/nio/ch/KQueue
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
sun/nio/ch
type FrameType
Native
truncated boolean
false
startTime long: millis
795008902917
state ThreadState
STATE_RUNNABLE

JVM: Runtime

ContinuationFreeze

experimental startTime duration eventThread stackTrace 19 21 23 24

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
default false false 0 ms
profiling false false 0 ms

Field Type Description
carrierThread Thread Carrier Thread Thread enlisted as a carrier
continuationClass Class Continuation Class Consider contributing a description to jfreventcollector.
interpretedFrames ushort Interpreted Frames
size ushort: bytes Stack Size

ContinuationThaw

experimental startTime duration eventThread stackTrace 19 21 23 24

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
default false false 0 ms
profiling false false 0 ms

Field Type Description
carrierThread Thread Carrier Thread Thread enlisted as a carrier
continuationClass Class Continuation Class Consider contributing a description to jfreventcollector.
interpretedFrames ushort Interpreted Frames
size ushort: bytes Stack Size

ContinuationFreezeFast

experimental startTime eventThread 20 21 23 24

Category: Java Virtual Machine / Runtime

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default false
profiling false

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

ContinuationFreezeSlow

experimental startTime eventThread 20 21 23 24

Category: Java Virtual Machine / Runtime

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default false
profiling false

Field Type Description
id ulong Continuation ID

ContinuationThawFast

experimental startTime eventThread 20 21 23 24

Category: Java Virtual Machine / Runtime

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default false
profiling false

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

ContinuationThawSlow

experimental startTime eventThread 20 21 23 24

Category: Java Virtual Machine / Runtime

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default false
profiling false

Field Type Description
id ulong Continuation ID

ReservedStackActivation

default profiling startTime eventThread stackTrace 11 17 21 23 24

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
default true true
profiling true true

Field Type Description
method Method Java Method

SafepointBegin

default profiling startTime duration eventThread 11 17 21 23 24 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
default true 10 ms
profiling true 0 ms

Field Type Description
safepointId ulong Safepoint Identifier
totalThreadCount int Total Threads The total number of threads at the start of safe point
jniCriticalThreadCount int JNI Critical Threads The number of threads in JNI critical sections

Examples 3
jniCriticalThreadCount int
0
safepointId ulong
38
startTime long: millis
1859602375
totalThreadCount int
21
jniCriticalThreadCount int
0
safepointId ulong
1960
startTime long: millis
839606684417
totalThreadCount int
150
jniCriticalThreadCount int
0
safepointId ulong
52
startTime long: millis
7959333833
totalThreadCount int
46

SafepointStateSynchronization

startTime duration eventThread 11 17 21 23 24

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:

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_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
default false 10 ms
profiling false 0 ms

Field Type Description
safepointId ulong Safepoint Identifier
initialThreadCount int Initial Threads The number of threads running at the beginning of state check
runningThreadCount int Running Threads The number of threads still running
iterations int Iterations Number of state check iterations

Examples 3
initialThreadCount int
1
iterations int
1165
runningThreadCount int
0
safepointId ulong
1907
startTime long: millis
796772691083
initialThreadCount int
2
iterations int
3
runningThreadCount int
0
safepointId ulong
71
startTime long: millis
8756644500
initialThreadCount int
4
iterations int
6
runningThreadCount int
0
safepointId ulong
87
startTime long: millis
7029690708

SafepointEnd

startTime duration eventThread 11 17 21 23 24 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:

                                             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_end_event(EventSafepointEnd& event, uint64_t safepoint_id) {
  if (event.should_commit()) {
    event.set_safepointId(safepoint_id);
    event.commit();
  }
}

// SafepointCheck
SafepointStateTracker::SafepointStateTracker(uint64_t safepoint_id, bool at_safepoint)
  : _safepoint_id(safepoint_id), _at_safepoint(at_safepoint) {}

bool SafepointStateTracker::safepoint_state_changed() {

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

  } // ~JavaThreadIteratorWithHandle

  // Release threads lock, so threads can be created/destroyed again.
  Threads_lock->unlock();

  // Wake threads after local state is correctly set.
  _wait_barrier->disarm();
}

// Wake up all threads, so they are ready to resume execution after the safepoint
// operation has been carried out
void SafepointSynchronize::end() {
  assert(Threads_lock->owned_by_self(), "must hold Threads_lock");
  EventSafepointEnd event;
  assert(Thread::current()->is_VM_thread(), "Only VM thread can execute a safepoint");

  disarm_safepoint();

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

  SafepointTracing::end();

  post_safepoint_end_event(event, safepoint_id());
}

Configuration enabled threshold
default false 10 ms
profiling false 0 ms

Field Type Description
safepointId ulong Safepoint Identifier

Examples 3
safepointId ulong
91
startTime long: millis
18880704625
safepointId ulong
1951
startTime long: millis
833719277125
safepointId ulong
7
startTime long: millis
364495667

ExecuteVMOperation

default profiling startTime duration eventThread 11 17 21 23 24 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
default true 10 ms
profiling true 0 ms

Field Type Description
operation VMOperationType Operation Consider contributing a description to jfreventcollector.
safepoint boolean At Safepoint If the operation occurred at a safepoint
blocking boolean Caller Blocked If the calling thread was blocked until the operation was complete
caller Thread Caller Thread requesting operation. If non-blocking, will be set to 0 indicating thread is unknown
safepointId ulong Safepoint Identifier The safepoint (if any) under which this operation was completed

Examples 3
blocking boolean
true
caller Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
1
osName string
main
osThreadId long
8707
virtual boolean
false
operation VMOperationType
HandshakeAllThreads
safepoint boolean
false
safepointId ulong
0
startTime long: millis
6720294917
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
20
osName string
JFR Periodic Tasks
osThreadId long
33027
virtual boolean
false
operation VMOperationType
ClassLoaderStatsOperation
safepoint boolean
true
safepointId ulong
1908
startTime long: millis
798650623083
blocking boolean
true
caller Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-16
javaThreadId long
90
osName string
UCT-akka.actor.default-dispatcher-16
osThreadId long
61699
virtual boolean
false
operation VMOperationType
ICBufferFull
safepoint boolean
true
safepointId ulong
64
startTime long: millis
8754194333

Shutdown

default profiling startTime eventThread stackTrace 11 17 21 23 24

Category: Java Virtual Machine / Runtime

JVM shutting down

Code Context

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

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

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

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/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();

Configuration enabled stackTrace
default true true
profiling true true

Field Type Description
reason string Reason Reason for JVM shutdown

Examples 3
reason string
Shutdown requested from Java
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
264
name string
beforeHalt
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
32
name string
java/lang/Shutdown
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
94066455250
reason string
Shutdown requested from Java
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
264
name string
beforeHalt
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
32
name string
java/lang/Shutdown
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
98967385458
reason string
No remaining non-daemon Java threads
stackTrace StackTrace
null
startTime long: millis
940851933500

SymbolTableStatistics

default profiling startTime duration every chunk 13 17 21 23 24

Category: Java Virtual Machine / Runtime / Tables

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true 10 s
profiling true 10 s

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

Examples 3
bucketCount ulong
32768
bucketCountAverage float
5.020691
bucketCountMaximum ulong
18
bucketCountStandardDeviation float
2.2593527
bucketCountVariance float
5.1046743
entryCount ulong
164518
insertionRate float
3.701437
removalRate float
0.9740624
startTime long: millis
98631548708
totalFootprint ulong: bytes
14301672
bucketCount ulong
65536
bucketCountAverage float
7.767639
bucketCountMaximum ulong
21
bucketCountStandardDeviation float
2.7926807
bucketCountVariance float
7.799066
entryCount ulong
509060
insertionRate float
0.09782524
removalRate float
0.0
startTime long: millis
839841975500
totalFootprint ulong: bytes
54764784
bucketCount ulong
32768
bucketCountAverage float
2.537384
bucketCountMaximum ulong
11
bucketCountStandardDeviation float
1.6110258
bucketCountVariance float
2.5954041
entryCount ulong
83145
insertionRate float
54598.0
removalRate float
11831.0
startTime long: millis
10650465500
totalFootprint ulong: bytes
6187440

StringTableStatistics

default profiling startTime duration every chunk 13 17 21 23 24

Category: Java Virtual Machine / Runtime / Tables

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true 10 s
profiling true 10 s

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

Examples 3
bucketCount ulong
65536
bucketCountAverage float
0.1854248
bucketCountMaximum ulong
4
bucketCountStandardDeviation float
0.43189627
bucketCountVariance float
0.18653439
entryCount ulong
12152
insertionRate float
7.4777584
removalRate float
0.29911032
startTime long: millis
24980481750
totalFootprint ulong: bytes
1487776
bucketCount ulong
65536
bucketCountAverage float
1.8220978
bucketCountMaximum ulong
10
bucketCountStandardDeviation float
1.3467039
bucketCountVariance float
1.8136114
entryCount ulong
119413
insertionRate float
5.6370516
removalRate float
0.9719054
startTime long: millis
937661141292
totalFootprint ulong: bytes
12202312
bucketCount ulong
65536
bucketCountAverage float
0.34371948
bucketCountMaximum ulong
6
bucketCountStandardDeviation float
0.5813279
bucketCountVariance float
0.33794212
entryCount ulong
22526
insertionRate float
1223.0361
removalRate float
193.10052
startTime long: millis
32373892667
totalFootprint ulong: bytes
2499552

ThreadDump

default profiling startTime duration every chunk 11 17 21 23 24

Category: Java Virtual Machine / Runtime

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true everyChunk
profiling true 60 s

Field Type Description
result string Thread Dump

Examples 3
result string
2024-09-25 14:24:36 Full thread dump OpenJDK 64-Bit Server VM (22+36 mixed mode, sharing): Threads class SMR info: _java_thread_list=0x0000600006146140, length=116, elements={ 0x000000014c808c00, 0x000000013d835200, 0x000000014c863a00, 0x000000013c81ac00, 0x000000013d835a00, 0x000000013c812a00, 0x0
startTime long: millis
874049188417
result string
2023-12-18 12:45:49 Full thread dump OpenJDK 64-Bit Server VM (21.0.1+12-LTS mixed mode): Threads class SMR info: _java_thread_list=0x00006000003cd500, length=77, elements={ 0x000000011f00f200, 0x000000010e038800, 0x000000010e03b200, 0x000000011f80ec00, 0x000000011f80c800, 0x000000011f811600, 0x000
startTime long: millis
63501309417
result string
2023-12-18 12:47:28 Full thread dump OpenJDK 64-Bit Server VM (21.0.1+12-LTS mixed mode): Threads class SMR info: _java_thread_list=0x000060000092cca0, length=77, elements={ 0x0000000132812000, 0x0000000131017000, 0x0000000131014c00, 0x000000013203b200, 0x0000000132008200, 0x0000000132009600, 0x000
startTime long: millis
67214999000

NativeLibrary

default profiling startTime every chunk 11 17 21 23 24

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
default true everyChunk
profiling true everyChunk

Field Type Description
name string Name
baseAddress ulong: address Base Address Starting address of the module
topAddress ulong: address Top Address Ending address of the module, if available

Examples 3
baseAddress ulong: address
8394989568
name string
/System/Library/Frameworks/CoreTransferable.framework/Versions/A/CoreTransferable
startTime long: millis
423214667
topAddress ulong: address
0
baseAddress ulong: address
10182955008
name string
/System/Library/PrivateFrameworks/WritingTools.framework/Versions/A/WritingTools
startTime long: millis
791772826333
topAddress ulong: address
0
baseAddress ulong: address
4303388672
name string
[...]/.sdkman/candidates/java/21.0.1-tem/lib/libjli.dylib
startTime long: millis
364596583
topAddress ulong: address
0

NativeLibraryLoad

default profiling startTime duration eventThread stackTrace 22 23 24

Category: Java Virtual Machine / Runtime

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

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), _fp_env_correction_attempt(false), _fp_env_correction_success(false) {
  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;
}

static void set_additional_data(EventNativeLibraryLoad& event, const NativeLibraryLoadEvent& helper) {
  event.set_fpuCorrectionAttempt(helper.get_fp_env_correction_attempt());
  event.set_fpuCorrectionSuccess(helper.get_fp_env_correction_success());
}

static void set_additional_data(EventNativeLibraryUnload& event, const NativeLibraryUnloadEvent& helper) {
  // no additional entries atm. for the unload event
}

template <typename EventType, typename HelperType>
static void commit(const HelperType& helper) {
  if (!helper.has_start_time()) {

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

  assert(thread != nullptr, "invariant");
  if (thread->is_Java_thread()) {
    JavaThread* jt = JavaThread::cast(thread);
    if (jt->thread_state() == _thread_in_native) {
      // For a JavaThread to take a JFR stacktrace, it must be in _thread_in_vm. Can safepoint here.
      MACOS_AARCH64_ONLY(ThreadWXEnable __wx(WXWrite, jt));
      ThreadInVMfromNative transition(jt);
      event.commit();
      return;
    }
    // If a thread comes here still _thread_in_Java, which can happen for example
    // when loading the disassembler library in response to traps in JIT code - all is ok.
    // Since there is no ljf, an event will be committed without a stacktrace.
  }
  event.commit();
}

NativeLibraryLoadEvent::~NativeLibraryLoadEvent() {
  commit<EventNativeLibraryLoad>(*this);
}

NativeLibraryUnloadEvent::~NativeLibraryUnloadEvent() {
  commit<EventNativeLibraryUnload>(*this);
}

Configuration enabled stackTrace threshold
default true true 0 ms
profiling 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
fpuCorrectionAttempt boolean 23+ FPU Environment Correction In case of IEEE conformance issues we might reset the FP environment
fpuCorrectionSuccess boolean 23+ FPU Environment Correction Result Stores the result in the case of an FP environment correction

Examples 1
errorMessage string
dlopen(/Library/Java/Extensions/libhadoop.dylib, 0x0001): tried: '/Library/Java/Extensions/libhadoop.dylib' (no such file), '/System/Volumes/Preboot/Cryptexes/OS/Library/Java/Extensions/libhadoop.dylib' (no such file), '/Library/Java/Extensions/libhadoop.dylib' (no such file)
name string
/Library/Java/Extensions/libhadoop.dylib
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljdk/internal/loader/NativeLibraries$NativeLibraryImpl;Ljava/lang/String;ZZ)Z
hidden boolean
false
modifiers int
266
name string
load
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
jdk/internal/loader/NativeLibraries
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
jdk/internal/loader
type FrameType
Native
truncated boolean
false
startTime long: millis
858012818417
success boolean
false

NativeLibraryUnload

default profiling startTime duration eventThread stackTrace 22 23 24

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), _fp_env_correction_attempt(false), _fp_env_correction_success(false) {
  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;
}

static void set_additional_data(EventNativeLibraryLoad& event, const NativeLibraryLoadEvent& helper) {
  event.set_fpuCorrectionAttempt(helper.get_fp_env_correction_attempt());
  event.set_fpuCorrectionSuccess(helper.get_fp_env_correction_success());
}

static void set_additional_data(EventNativeLibraryUnload& event, const NativeLibraryUnloadEvent& helper) {
  // no additional entries atm. for the unload event
}

template <typename EventType, typename HelperType>
static void commit(const 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:

  assert(thread != nullptr, "invariant");
  if (thread->is_Java_thread()) {
    JavaThread* jt = JavaThread::cast(thread);
    if (jt->thread_state() == _thread_in_native) {
      // For a JavaThread to take a JFR stacktrace, it must be in _thread_in_vm. Can safepoint here.
      MACOS_AARCH64_ONLY(ThreadWXEnable __wx(WXWrite, jt));
      ThreadInVMfromNative transition(jt);
      event.commit();
      return;
    }
    // If a thread comes here still _thread_in_Java, which can happen for example
    // when loading the disassembler library in response to traps in JIT code - all is ok.
    // Since there is no ljf, an event will be committed without a stacktrace.
  }
  event.commit();
}

NativeLibraryLoadEvent::~NativeLibraryLoadEvent() {
  commit<EventNativeLibraryLoad>(*this);
}

NativeLibraryUnloadEvent::~NativeLibraryUnloadEvent() {
  commit<EventNativeLibraryUnload>(*this);
}

Configuration enabled stackTrace threshold
default true true 0 ms
profiling 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

default profiling startTime every chunk 11 17 21 23 24

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
default true endChunk
profiling true endChunk

Field Type Description
source Module Source Module
requiredModule Module Required Module Consider contributing a description to jfreventcollector.

Examples 3
requiredModule Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
source Module
classLoader ClassLoader
name string
platform
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
32
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
21.0.1
name string
jdk/internal/loader
location string
jrt:/jdk.httpserver
name string
jdk.httpserver
version string
21.0.1
startTime long: millis
16763952708
requiredModule Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
source Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/jdk.nio.mapmode
name string
jdk.nio.mapmode
version string
21.0.1
startTime long: millis
14998474333
requiredModule Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/net
location string
null
name string
null
version string
null
source Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/net
location string
null
name string
jdk.proxy4
version string
null
startTime long: millis
795760285625

ModuleExport

default profiling startTime every chunk 11 17 21 23 24

Category: Java Virtual Machine / Runtime / Modules

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

Field Type Description
exportedPackage Package Exported Package Consider contributing a description to jfreventcollector.
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
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/concurrent/duration
startTime long: millis
16764024625
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
22
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection/convert/impl
startTime long: millis
795760593292
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
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection
startTime long: millis
14998523917
targetModule Module
null

Java Application

ThreadStart

default profiling startTime eventThread stackTrace 11 17 21 23 24 graal vm

Category: Java Application

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

Examples 3
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-ask-thread-pool-34
javaThreadId long
1752
osName string
block-manager-ask-thread-pool-34
osThreadId long
65571
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
2
lineNumber int
2582
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
22
name string
java/lang
type FrameType
Inlined
truncated boolean
false
startTime long: millis
791551338167
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-ask-thread-pool-35
javaThreadId long
1753
osName string
block-manager-ask-thread-pool-35
osThreadId long
51991
virtual boolean
false
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
main
javaThreadId long
1
osName string
main
osThreadId long
8707
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
2
lineNumber int
2573
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
32
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
21.0.1
name string
java/lang
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
6720543458
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.internal-dispatcher-2
javaThreadId long
41
osName string
UCT-akka.actor.internal-dispatcher-2
osThreadId long
27403
virtual boolean
false
parentThread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-11
javaThreadId long
131
osName string
UCT-akka.actor.default-dispatcher-11
osThreadId long
48135
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
2
lineNumber int
2573
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
32
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
21.0.1
name string
java/lang
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
12610050333
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-18
javaThreadId long
137
osName string
UCT-akka.actor.default-dispatcher-18
osThreadId long
46343
virtual boolean
false

ThreadEnd

default profiling startTime eventThread 11 17 21 23 24 graal vm

Category: Java Application

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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:

    JVMCI::shutdown(thread);
  }
#endif

#if INCLUDE_CDS
  ClassListWriter::write_resolved_constants();
#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
default true
profiling true

Field Type Description
thread Thread Java Thread

Examples 3
startTime long: millis
845382287375
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
task-result-getter-3
javaThreadId long
1658
osName string
task-result-getter-3
osThreadId long
99099
virtual boolean
false
startTime long: millis
15749250917
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-16
javaThreadId long
135
osName string
UCT-akka.actor.default-dispatcher-16
osThreadId long
50183
virtual boolean
false
startTime long: millis
17495244250
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-9
javaThreadId long
98
osName string
UCT-akka.actor.default-dispatcher-9
osThreadId long
34823
virtual boolean
false

ThreadPark

default profiling startTime duration eventThread stackTrace 11 17 21 23 24 graal vm

Category: Java Application

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true true 20 ms
profiling true true 10 ms

Field Type Description
parkedClass Class Class Parked On
timeout long: nanos Park Timeout
until long: epochmillis Park Until
address ulong: address Address of Object Parked

Examples 3
address ulong: address
30156597904
parkedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
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
21.0.1
name string
java/util/concurrent
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
49
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
21.0.1
name string
jdk/internal/misc
type FrameType
Native
truncated boolean
false
startTime long: millis
5915698667
timeout long: nanos
-9223372036854775808
until long: epochmillis
-9223372036854775808
address ulong: address
30121492296
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
22
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
22
name string
jdk/internal/misc
type FrameType
Native
truncated boolean
false
startTime long: millis
794895652708
timeout long: nanos
-9223372036854775808
until long: epochmillis
-9223372036854775808
address ulong: address
31586136128
parkedClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
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
21.0.1
name string
java/util/concurrent
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(ZJ)V
hidden boolean
false
modifiers int
257
name string
park
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
49
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
21.0.1
name string
jdk/internal/misc
type FrameType
Native
truncated boolean
false
startTime long: millis
5613112208
timeout long: nanos
-9223372036854775808
until long: epochmillis
-9223372036854775808

JavaMonitorEnter

default profiling startTime duration eventThread stackTrace 11 17 21 23 24 graal vm

Category: Java Application

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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:

  // At this point this ObjectMonitor cannot be deflated, finish contended enter
  enter_with_contention_mark(current, contention_mark);
  return true;
}

void ObjectMonitor::enter_with_contention_mark(JavaThread *current, ObjectMonitorContentionMark &cm) {
  assert(current == JavaThread::current(), "must be");
  assert(owner_raw() != current, "must be");
  assert(cm._monitor == this, "must be");
  assert(!is_being_async_deflated(), "must be");

  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:

      return;
    }
  }

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

#if INCLUDE_JFR
  // get the owner's thread id for the MonitorEnter event
  // if it is enabled and the thread isn't suspended
  if (not_suspended && EventJavaMonitorEnter::is_enabled()) {
    _previous_owner_tid = JFR_THREAD_ID(current);
  }
#endif

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

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

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

Field Type Description
monitorClass Class Monitor Class Consider contributing a description to jfreventcollector.
previousOwner Thread Previous Monitor Owner
address ulong: address Monitor Address

Examples 3
address ulong: address
105553170730032
monitorClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hidden boolean
false
modifiers int
33
name string
edu/rice/habanero/actors/AkkaActorState$actorLatch$
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
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
edu/rice/habanero/actors
previousOwner Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-5
javaThreadId long
45
osName string
UCT-akka.actor.default-dispatcher-5
osThreadId long
28167
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
-1
lineNumber int
115
method Method
descriptor string
()V
hidden boolean
false
modifiers int
33
name string
countUp
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hidden boolean
false
modifiers int
33
name string
edu/rice/habanero/actors/AkkaActorState$actorLatch$
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
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
edu/rice/habanero/actors
type FrameType
Inlined
truncated boolean
false
startTime long: millis
7504717708
address ulong: address
105553210298640
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/lang
previousOwner Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
shuffle-client-5-7
javaThreadId long
1848
osName string
shuffle-client-5-7
osThreadId long
170519
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
572
method Method
descriptor string
(Ljava/lang/String;Z)Ljava/lang/Class;
hidden boolean
false
modifiers int
4
name string
loadClass
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1025
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/lang
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
847425148000
address ulong: address
105553176308912
monitorClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hidden boolean
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modifiers int
33
name string
edu/rice/habanero/actors/AkkaActorState$actorLatch$
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
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
edu/rice/habanero/actors
previousOwner Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-7
javaThreadId long
54
osName string
UCT-akka.actor.default-dispatcher-7
osThreadId long
35331
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
-1
lineNumber int
109
method Method
descriptor string
()V
hidden boolean
false
modifiers int
33
name string
countDown
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
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21.0.1
name string
java/net
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33
name string
edu/rice/habanero/actors/AkkaActorState$actorLatch$
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module Module
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null
type Class
classLoader ClassLoader
name string
bootstrap
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null
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false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
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null
location string
jrt:/java.base
name string
java.base
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21.0.1
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java/net
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null
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null
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edu/rice/habanero/actors
type FrameType
Inlined
truncated boolean
false
startTime long: millis
8108352583

JavaMonitorWait

default profiling startTime duration eventThread stackTrace 11 17 21 23 24 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::jdk_jfr_internal_management_HiddenWait() == 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
default true true 20 ms
profiling true true 10 ms

Field Type Description
monitorClass Class Monitor Class Class of object waited on
notifier Thread Notifier Thread Notifying Thread
timeout long: millis Timeout Maximum wait time
timedOut boolean Timed Out Wait has been timed out
address ulong: address Monitor Address Address of object waited on

Examples 3
address ulong: address
105553167499680
monitorClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
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
21.0.1
name string
java/lang
notifier Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Thread-24
javaThreadId long
349
osName string
Thread-24
osThreadId long
46367
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
274
name string
wait0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
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
21.0.1
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
67992197083
timedOut boolean
false
timeout long: millis
0
address ulong: address
105553345132768
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
22
name string
java/net
hidden boolean
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modifiers int
9
name string
org/renaissance/scala/stm/RealityShowPhilosophers$CameraThread
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
22
name string
java/net
location string
null
name string
null
version string
null
name string
org/renaissance/scala/stm
notifier Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
Thread-360
javaThreadId long
1887
osName string
Thread-360
osThreadId long
39199
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
274
name string
wait0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
854788144917
timedOut boolean
false
timeout long: millis
0
address ulong: address
105553176308912
monitorClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
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21.0.1
name string
java/net
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33
name string
edu/rice/habanero/actors/AkkaActorState$actorLatch$
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exported boolean
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module Module
classLoader ClassLoader
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classLoader ClassLoader
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bootstrap
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null
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33
name string
java/net/URLClassLoader
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module Module
classLoader ClassLoader
name string
bootstrap
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null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
edu/rice/habanero/actors
notifier Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-18
javaThreadId long
115
osName string
UCT-akka.actor.default-dispatcher-18
osThreadId long
44551
virtual boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(J)V
hidden boolean
false
modifiers int
274
name string
wait0
type Class
classLoader ClassLoader
name string
bootstrap
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null
hidden boolean
false
modifiers int
33
name string
java/lang/Object
package Package
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true
module Module
classLoader ClassLoader
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bootstrap
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null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
10801087542
timedOut boolean
false
timeout long: millis
0

JavaMonitorInflate

profiling startTime duration eventThread stackTrace 11 17 21 23 24 graal vm

Category: Java Application

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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) {

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

  assert(current == Thread::current(), "must be");
  assert(LockingMode != LM_LIGHTWEIGHT, "only inflate through enter");
  return inflate_impl(obj, cause);
}

ObjectMonitor* ObjectSynchronizer::inflate_for(JavaThread* thread, oop obj, const InflateCause cause) {
  assert(thread == Thread::current() || thread->is_obj_deopt_suspend(), "must be");
  assert(LockingMode != LM_LIGHTWEIGHT, "LM_LIGHTWEIGHT cannot use inflate_for");
  return inflate_impl(obj, cause);
}

ObjectMonitor* ObjectSynchronizer::inflate_impl(oop object, const InflateCause cause) {
  assert(LockingMode != LM_LIGHTWEIGHT, "LM_LIGHTWEIGHT cannot use inflate_impl");
  EventJavaMonitorInflate event;

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

    // The mark can be in one of the following states:
    // *  inflated     - Just return it.
    // *  stack-locked - Coerce it to inflated from stack-locked.
    // *  INFLATING    - Busy wait for conversion from stack-locked to
    //                   inflated.
    // *  unlocked     - Aggressively inflate the object.

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

static void log_inflate(Thread* current, oop object, ObjectSynchronizer::InflateCause cause) {
  if (log_is_enabled(Trace, monitorinflation)) {
    ResourceMark rm(current);
    log_trace(monitorinflation)("inflate: object=" INTPTR_FORMAT ", mark="
                                INTPTR_FORMAT ", type='%s' cause=%s", p2i(object),
                                object->mark().value(), object->klass()->external_name(),
                                ObjectSynchronizer::inflate_cause_name(cause));
  }
}

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();
}

ObjectMonitor* LightweightSynchronizer::get_or_insert_monitor(oop object, JavaThread* current, ObjectSynchronizer::InflateCause cause) {
  assert(UseObjectMonitorTable, "must be");

  EventJavaMonitorInflate event;

  bool inserted;
  ObjectMonitor* monitor = get_or_insert_monitor_from_table(object, current, &inserted);

  if (inserted) {
    // Hopefully the performance counters are allocated on distinct
    // cache lines to avoid false sharing on MP systems ...
    OM_PERFDATA_OP(Inflations, inc());
    log_inflate(current, object, cause);
    if (event.should_commit()) {
      post_monitor_inflate_event(&event, object, cause);

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

ObjectMonitor* LightweightSynchronizer::inflate_into_object_header(oop object, ObjectSynchronizer::InflateCause cause, JavaThread* inflating_thread, Thread* current) {

  // The JavaThread* inflating_thread parameter is only used by LM_LIGHTWEIGHT and requires
  // that the inflating_thread == Thread::current() or is suspended throughout the call by
  // some other mechanism.
  // Even with LM_LIGHTWEIGHT the thread might be nullptr when called from a non
  // JavaThread. (As may still be the case from FastHashCode). However it is only
  // important for the correctness of the LM_LIGHTWEIGHT algorithm that the thread
  // is set when called from ObjectSynchronizer::enter from the owning thread,
  // ObjectSynchronizer::enter_for from any thread, or ObjectSynchronizer::exit.
  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 inflating_thread owns the
    //                   object lock, then we make the inflating_thread
    //                   the ObjectMonitor owner and remove the lock from
    //                   the inflating_thread's lock stack.

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

Field Type Description
monitorClass Class Monitor Class Consider contributing a description to jfreventcollector.
address ulong: address Monitor Address
cause InflateCause Monitor Inflation Cause Cause of inflation

ObjectAllocationInNewTLAB

startTime eventThread stackTrace 11 17 21 23 24 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
default false true
profiling false true

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

Examples 3
allocationSize ulong: bytes
144
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
[I
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
143
lineNumber int
1934
method Method
descriptor string
()V
hidden boolean
false
modifiers int
2
name string
compile
type Class
classLoader ClassLoader
name string
bootstrap
type Class
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hidden boolean
false
modifiers int
49
name string
java/util/regex/Pattern
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
21.0.1
name string
java/util/regex
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
1133899583
tlabSize ulong: bytes
1314912
allocationSize ulong: bytes
2176
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
15
lineNumber int
3540
method Method
descriptor string
([BI)[B
hidden boolean
false
modifiers int
9
name string
copyOf
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
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modifiers int
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name string
java/util/Arrays
package Package
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module Module
classLoader ClassLoader
name string
bootstrap
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null
location string
jrt:/java.base
name string
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version string
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name string
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JIT compiled
truncated boolean
false
startTime long: millis
792254932250
tlabSize ulong: bytes
28608
allocationSize ulong: bytes
88
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
49
name string
java/util/regex/Pattern
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
21.0.1
name string
java/util/regex
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
1101
method Method
descriptor string
(Ljava/lang/String;)Ljava/util/regex/Pattern;
hidden boolean
false
modifiers int
9
name string
compile
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
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modifiers int
49
name string
java/util/regex/Pattern
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
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21.0.1
name string
java/util/regex
type FrameType
Interpreted
truncated boolean
false
startTime long: millis
960832250
tlabSize ulong: bytes
1434008

ObjectAllocationOutsideTLAB

startTime eventThread stackTrace 11 17 21 23 24

Category: Java Application

Allocation outside Thread Local Allocation Buffers

Code Context

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

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

#if INCLUDE_JFR
#include "jfr/support/jfrAllocationTracer.hpp"
#endif

void AllocTracer::send_allocation_outside_tlab(Klass* klass, HeapWord* obj, size_t alloc_size, JavaThread* thread) {
  JFR_ONLY(JfrAllocationTracer tracer(klass, obj, alloc_size, true, thread);)
  EventObjectAllocationOutsideTLAB event;
  if (event.should_commit()) {
    event.set_objectClass(klass);
    event.set_allocationSize(alloc_size);
    event.commit();
  }
}

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

Configuration enabled stackTrace
default false true
profiling false true

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

Examples 3
allocationSize ulong: bytes
24
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
[B
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
10
lineNumber int
3863
method Method
descriptor string
([BII)[B
hidden boolean
false
modifiers int
10
name string
copyOfRangeByte
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
49
name string
java/util/Arrays
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util
type FrameType
Inlined
truncated boolean
false
startTime long: millis
1175917833
allocationSize ulong: bytes
32952
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[B
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
50
lineNumber int
104
method Method
descriptor string
(Ljava/io/OutputStream;ILnet/jpountz/lz4/LZ4Compressor;Ljava/util/zip/Checksum;Z)V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/net
hidden boolean
false
modifiers int
1
name string
net/jpountz/lz4/LZ4BlockOutputStream
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
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null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
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bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
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
801290700208
allocationSize ulong: bytes
7056
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
[Ljava/lang/Object;
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/lang
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
3513
method Method
descriptor string
([Ljava/lang/Object;ILjava/lang/Class;)[Ljava/lang/Object;
hidden boolean
false
modifiers int
9
name string
copyOf
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
49
name string
java/util/Arrays
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
2020327167

ObjectAllocationSample

throttle default profiling startTime eventThread stackTrace 16 17 21 23 24 graal vm

Category: Java Application

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true true 150/s
profiling true true 300/s

Field Type Description
objectClass Class Object Class Class of allocated object
weight long: bytes Sample Weight The relative weight of the sample. Aggregating the weights for a large number of samples, for a particular class, thread or stack trace, gives a statistically accurate representation of the allocation pressure

Examples 3
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
49
name string
java/util/regex/Pattern
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util/regex
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
1101
method Method
descriptor string
(Ljava/lang/String;)Ljava/util/regex/Pattern;
hidden boolean
false
modifiers int
9
name string
compile
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
49
name string
java/util/regex/Pattern
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util/regex
type FrameType
Inlined
truncated boolean
false
startTime long: millis
1124923958
weight long: bytes
1313736
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
[I
package Package
null
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
143
lineNumber int
1934
method Method
descriptor string
()V
hidden boolean
false
modifiers int
2
name string
compile
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
49
name string
java/util/regex/Pattern
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util/regex
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
1038790500
weight long: bytes
1393456
objectClass Class
classLoader ClassLoader
name string
bootstrap
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null
hidden boolean
false
modifiers int
1
name string
java/util/HashMap
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
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name string
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34
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89
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descriptor string
(Ljava/lang/String;Ljava/lang/String;)V
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classLoader ClassLoader
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classLoader ClassLoader
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bootstrap
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null
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false
modifiers int
1
name string
java/net/URLClassLoader
package Package
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true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
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22
name string
java/net
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org/apache/logging/log4j/spi/DefaultThreadContextMap
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classLoader ClassLoader
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classLoader ClassLoader
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Interpreted
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startTime long: millis
792255406458
weight long: bytes
221952

JavaExceptionThrow

startTime duration 11 17 21 23 24

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

Category: Java Application

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

Configuration enabled stackTrace
default false true
profiling false true

Field Type Description
message string Message Consider contributing a description to jfreventcollector.
thrownClass Class Class Consider contributing a description to jfreventcollector.

Examples 3
message string
org.renaissance.harness.ConfigParser$$anon$1
startTime long: millis
580902583
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/lang/ClassNotFoundException
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/lang
message string
scala.Product
startTime long: millis
667748750
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/lang/ClassNotFoundException
package Package
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module Module
classLoader ClassLoader
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bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/lang
message string
null
startTime long: millis
792248652833
thrownClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
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false
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name string
java/net/URLClassLoader
package Package
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module Module
classLoader ClassLoader
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bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/net
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scala/runtime/NonLocalReturnControl
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true
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classLoader ClassLoader
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classLoader ClassLoader
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bootstrap
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java/net/URLClassLoader
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module Module
classLoader ClassLoader
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null
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jrt:/java.base
name string
java.base
version string
22
name string
java/net
location string
null
name string
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version string
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name string
scala/runtime

FileWrite

default profiling startTime duration 11 17 21 23 24

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

Category: Java Application

Excludes in stack trace: java.io.FileOutputStream, java.io.RandomAccessFile, sun.nio.ch.FileChannelImpl

Appearing in: G1GC, ParallelGC, ShenandoahGC, ZGC

Missing in: SerialGC

Writing data to a file

Code Context

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

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

/**
 * This class registers all mirror events.
 */
final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadPinnedEvent", VirtualThreadPinnedEvent.class);

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

@Name(Type.EVENT_NAME_PREFIX + "FileWrite")
@Label("File Write")
@Category("Java Application")
@Description("Writing data to a file")
@StackFilter({"java.io.FileOutputStream", "java.io.RandomAccessFile", "sun.nio.ch.FileChannelImpl"})
public final class FileWriteEvent extends MirrorEvent {

    @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
    public long bytesWritten;
}

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

    @Override
    public int write(ByteBuffer src) throws IOException {
        if (jfrTracing && FileWriteEvent.enabled()) {
            return traceImplWrite(src);

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

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

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

    @Override
    public long write(ByteBuffer[] srcs, int offset, int length) throws IOException {
        if (jfrTracing && FileWriteEvent.enabled()) {
            return traceImplWrite(srcs, offset, length);

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

        long bytesWritten = 0;
        long start = 0;
        try {
            start = FileWriteEvent.timestamp();
            bytesWritten = implWrite(srcs, offset, length);
        } finally {
            long duration = FileWriteEvent.timestamp() - start;
            if (FileWriteEvent.shouldCommit(duration)) {
                long bytes = bytesWritten > 0 ? bytesWritten : 0;
                FileWriteEvent.commit(start, duration, path, bytes);
            }

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

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

src/java.base/share/classes/java/io/FileOutputStream.java:

    private void traceWrite(int b, boolean append) throws IOException {
        long bytesWritten = 0;
        long start = 0;
        try {
            start = FileWriteEvent.timestamp();
            write(b, append);
            bytesWritten = 1;
        } finally {
            long duration = FileWriteEvent.timestamp() - start;
            if (FileWriteEvent.shouldCommit(duration)) {
                FileWriteEvent.commit(start, duration, path, bytesWritten);
            }
        }

src/java.base/share/classes/java/io/FileOutputStream.java:

     */
    @Override
    public void write(int b) throws IOException {
        boolean append = FD_ACCESS.getAppend(fd);
        if (jfrTracing && FileWriteEvent.enabled()) {
            traceWrite(b, append);
            return;

src/java.base/share/classes/java/io/FileOutputStream.java:

    private void traceWriteBytes(byte b[], int off, int len, boolean append) throws IOException {
        long bytesWritten = 0;
        long start = 0;
        try {
            start = FileWriteEvent.timestamp();
            writeBytes(b, off, len, append);
            bytesWritten = len;
        } finally {
            long duration = FileWriteEvent.timestamp() - start;
            if (FileWriteEvent.shouldCommit(duration)) {
                FileWriteEvent.commit(start, duration, path, bytesWritten);
            }
        }

src/java.base/share/classes/java/io/FileOutputStream.java:

     */
    @Override
    public void write(byte[] b) throws IOException {
        boolean append = FD_ACCESS.getAppend(fd);
        if (jfrTracing && FileWriteEvent.enabled()) {
            traceWriteBytes(b, 0, b.length, append);
            return;

src/java.base/share/classes/java/io/FileOutputStream.java:

     */
    @Override
    public void write(byte[] b, int off, int len) throws IOException {
        boolean append = FD_ACCESS.getAppend(fd);
        if (jfrTracing && FileWriteEvent.enabled()) {
            traceWriteBytes(b, off, len, append);
            return;

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

package jdk.internal.event;

/**
 * Event recording file writes.
 */
public final class FileWriteEvent extends Event {

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

    public static boolean enabled() {
        // Generated by JFR
        return false;
    }

    public static long timestamp() {
        // Generated by JFR
        return 0L;
    }

    public static boolean shouldCommit(long duration) {
        // Generated by JFR
        return false;

src/java.base/share/classes/java/io/RandomAccessFile.java:

     * @param      b   the {@code byte} to be written.
     * @throws     IOException  if an I/O error occurs.
     */
    public void write(int b) throws IOException {
        if (jfrTracing && FileWriteEvent.enabled()) {
            traceImplWrite(b);
            return;
        }

src/java.base/share/classes/java/io/RandomAccessFile.java:

    private void traceImplWrite(int b) throws IOException {
        long bytesWritten = 0;
        long start = 0;
        try {
            start = FileWriteEvent.timestamp();
            implWrite(b);
            bytesWritten = 1;
        } finally {
            long duration = FileWriteEvent.timestamp() - start;
            if (FileWriteEvent.shouldCommit(duration)) {
                FileWriteEvent.commit(start, duration, path, bytesWritten);
            }
        }
    }

src/java.base/share/classes/java/io/RandomAccessFile.java:

     * @param     len the number of bytes that are written
     * @throws    IOException If an I/O error has occurred.
     */
    private void writeBytes(byte[] b, int off, int len) throws IOException {
        if (jfrTracing && FileWriteEvent.enabled()) {
            traceImplWriteBytes(b, off, len);
            return;
        }

src/java.base/share/classes/java/io/RandomAccessFile.java:

    private void traceImplWriteBytes(byte b[], int off, int len) throws IOException {
        long bytesWritten = 0;
        long start = 0;
        try {
            start = FileWriteEvent.timestamp();
            implWriteBytes(b, off, len);
            bytesWritten = len;
        } finally {
            long duration = FileWriteEvent.timestamp() - start;
            if (FileWriteEvent.shouldCommit(duration)) {
                FileWriteEvent.commit(start, duration, path, bytesWritten);
            }
        }
    }

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

Field Type Description
path string Path Full path of the file, or N/A if a file descriptor was used to create the stream, for example System.out and System.err
bytesWritten long: bytes Bytes Written Number of bytes written to the file

Examples 3
bytesWritten long: bytes
120
path string
null
startTime long: millis
56404662458
bytesWritten long: bytes
85803
path string
[...]/code/experiments/jfreventcollector/harness-141003-16632656921422798882/apache-spark/als/blockmgr-3624345d-f4f5-494f-a482-f63f3a3023ec/3c/shuffle_6_208_0.data.e3525a2a-52bc-4c33-a14c-eec5321adac3
startTime long: millis
809944337750
bytesWritten long: bytes
16384
path string
harness-124802-11372319207631724376/apache-spark/lib/spark-sql_2.13-3.2.0.jar
startTime long: millis
2721627083

VirtualThreadEnd

startTime duration 19 21 23 24

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

Category: Java Application

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadPinnedEvent", VirtualThreadPinnedEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
    };

    private static void register(String eventClassName, Class<? extends MirrorEvent> mirrorClass) {
        mirrorLookup.put(eventClassName, mirrorClass);

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")
@RemoveFields({"duration", "stackTrace"})
public final class VirtualThreadEndEvent extends MirrorEvent {

    @Label("Thread Id")
    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();
            }
        }
    }

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 static final VirtualThreadEndEvent EVENT = new VirtualThreadEndEvent();

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

    public long javaThreadId;
}

Configuration enabled
default false
profiling false

Field Type Description
javaThreadId long Thread Id

SocketRead

default profiling startTime duration 11 17 21 23 24

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/internal/MirrorEvents.java:

final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadPinnedEvent", VirtualThreadPinnedEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);

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

@Name(Type.EVENT_NAME_PREFIX + "SocketRead")
@Label("Socket Read")
@Category("Java Application")
@Description("Reading data from a socket")
public final class SocketReadEvent extends MirrorEvent {

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

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

    @Label("Remote Port")
    public int port;

    @Label("Timeout Value")

src/java.base/share/classes/java/net/Socket.java:

        @Override
        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 {
                return in.read(b, off, len);

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 {
        sc.close();

src/java.base/share/classes/sun/nio/ch/SocketChannelImpl.java:

        } finally {
            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;
    }

    /**
     * Marks the beginning of a write operation that might block.

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;

    /**

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

Field Type Description
host string Remote Host
address string Remote Address
port int Remote Port
timeout long: millis Timeout Value
bytesRead long: bytes Bytes Read Number of bytes read from the socket
endOfStream boolean End of Stream If end of stream was reached

Examples 3
address string
127.0.0.1
bytesRead long: bytes
1
endOfStream boolean
false
host string
port int
52656
startTime long: millis
50076812250
timeout long: millis
0
address string
127.0.0.1
bytesRead long: bytes
26
endOfStream boolean
false
host string
127.0.0.1
port int
56489
startTime long: millis
933488506792
timeout long: millis
0
address string
127.0.0.1
bytesRead long: bytes
39
endOfStream boolean
false
host string
port int
52501
startTime long: millis
85008396000
timeout long: millis
0

FileRead

default profiling startTime duration 11 17 21 23 24

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

Category: Java Application

Excludes in stack trace: java.io.FileInputStream, java.io.RandomAccessFile, sun.nio.ch.FileChannelImpl

Appearing in: G1GC, SerialGC, ZGC

Missing in: 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/internal/MirrorEvents.java:

/**
 * This class registers all mirror events.
 */
final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);

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

@Name(Type.EVENT_NAME_PREFIX + "FileRead")
@Label("File Read")
@Category("Java Application")
@Description("Reading data from a file")
@StackFilter({"java.io.FileInputStream", "java.io.RandomAccessFile", "sun.nio.ch.FileChannelImpl"})
public final class FileReadEvent extends MirrorEvent {

    @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
    public long bytesRead;

    @Label("End of File")

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

    @Override
    public int read(ByteBuffer dst) throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceImplRead(dst);

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

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

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

    @Override
    public long read(ByteBuffer[] dsts, int offset, int length) throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceImplRead(dsts, offset, length);

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

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

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

    @Override
    public int read(ByteBuffer dst, long position) throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceImplRead(dst, position);

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

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

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

    @Override
    public int write(ByteBuffer src, long position) throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceImplWrite(src, position);

src/java.base/share/classes/java/io/FileInputStream.java:

     */
    @Override
    public int read() throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceRead0();
        }

src/java.base/share/classes/java/io/FileInputStream.java:

        long bytesRead = 0;
        long start = 0;
        try {
            start = FileReadEvent.timestamp();
            result = read0();
            if (result < 0) {

src/java.base/share/classes/java/io/FileInputStream.java:

                bytesRead = 1;
            }
        } finally {
            long duration = FileReadEvent.timestamp() - start;
            if (FileReadEvent.shouldCommit(duration)) {
                FileReadEvent.commit(start, duration, path, bytesRead, endOfFile);
            }
        }

src/java.base/share/classes/java/io/FileInputStream.java:

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

src/java.base/share/classes/java/io/FileInputStream.java:

     */
    @Override
    public int read(byte[] b) throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceReadBytes(b, 0, b.length);
        }

src/java.base/share/classes/java/io/FileInputStream.java:

     */
    @Override
    public int read(byte[] b, int off, int len) throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceReadBytes(b, off, len);
        }

src/java.base/share/classes/java/io/RandomAccessFile.java:

     * @throws     IOException  if an I/O error occurs. Not thrown if
     *                          end-of-file has been reached.
     */
    public int read() throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceRead0();
        }

src/java.base/share/classes/java/io/RandomAccessFile.java:

        long bytesRead = 0;
        boolean endOfFile = false;
        long start = 0;
        try {
            start = FileReadEvent.timestamp();
            result = read0();
            if (result < 0) {

src/java.base/share/classes/java/io/RandomAccessFile.java:

            } else {
                bytesRead = 1;
            }
        } finally {
            long duration = FileReadEvent.timestamp() - start;
            if (FileReadEvent.shouldCommit(duration)) {
                FileReadEvent.commit(start, duration, path, bytesRead, endOfFile);
            }
        }

src/java.base/share/classes/java/io/RandomAccessFile.java:

     * @param     len the number of bytes to read.
     * @throws    IOException If an I/O error has occurred.
     */
    private int readBytes(byte[] b, int off, int len) throws IOException {
        if (jfrTracing && FileReadEvent.enabled()) {
            return traceReadBytes0(b, off, len);
        }

src/java.base/share/classes/java/io/RandomAccessFile.java:

    private int traceReadBytes0(byte b[], int off, int len) throws IOException {
        int bytesRead = 0;
        long start = 0;
        try {
            start = FileReadEvent.timestamp();
            bytesRead = readBytes0(b, off, len);
        } finally {
            long duration = FileReadEvent.timestamp() - start;
            if (FileReadEvent.shouldCommit(duration)) {
                if (bytesRead < 0) {
                    FileReadEvent.commit(start, duration, path, 0L, true);
                } else {
                    FileReadEvent.commit(start, duration, path, bytesRead, false);
                }
            }

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

package jdk.internal.event;

/**
 * Event recording file reads.
 */
public final class FileReadEvent extends Event {

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

    public static boolean enabled() {
        // Generated by JFR
        return false;
    }

    public static long timestamp() {
        // Generated by JFR
        return 0L;
    }

    public static boolean shouldCommit(long duration) {
        // Generated by JFR

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

Field Type Description
path string Path Full path of the file, 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 3
bytesRead long: bytes
4
endOfFile boolean
false
path string
[...]/code/experiments/jfreventcollector/harness-124622-12434569844652140370/apache-spark/lib/avro-ipc-1.10.2.jar
startTime long: millis
28227785042
bytesRead long: bytes
28072
endOfFile boolean
false
path string
[...]/code/experiments/jfreventcollector/harness-141003-16632656921422798882/apache-spark/als/blockmgr-3624345d-f4f5-494f-a482-f63f3a3023ec/09/shuffle_4_230_0.data
startTime long: millis
839849996667
bytesRead long: bytes
8192
endOfFile boolean
false
path string
[...]/code/experiments/jfreventcollector/.cache/renaissance.jar
startTime long: millis
3341103166

VirtualThreadPinned

default profiling startTime duration 19 21 23 24

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

Category: Java Application

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadPinnedEvent", VirtualThreadPinnedEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
    };

    private static void register(String eventClassName, Class<? extends MirrorEvent> mirrorClass) {
        mirrorLookup.put(eventClassName, mirrorClass);
    }

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")
public final class VirtualThreadPinnedEvent extends MirrorEvent {
}

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) {

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

    @JvmtiMountTransition
    private static native void notifyJvmtiHideFrames(boolean hide);

    @IntrinsicCandidate
    private static native void notifyJvmtiDisableSuspend(boolean enter);

    private static native void registerNatives();
    static {
        registerNatives();

        // ensure VTHREAD_GROUP is created, may be accessed by JVMTI
        var group = Thread.virtualThreadGroup();

        // ensure VirtualThreadPinnedEvent is loaded/initialized
        U.ensureClassInitialized(VirtualThreadPinnedEvent.class);
    }

    /**
     * Creates the default ForkJoinPool scheduler.
     */
    @SuppressWarnings("removal")
    private static ForkJoinPool createDefaultScheduler() {
        ForkJoinWorkerThreadFactory factory = pool -> {
            PrivilegedAction<ForkJoinWorkerThread> pa = () -> new CarrierThread(pool);
            return AccessController.doPrivileged(pa);
        };

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 {
}

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

ThreadSleep

default profiling startTime duration 11 17 21 23 24

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

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadPinnedEvent", VirtualThreadPinnedEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
    };

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")
@StackFilter({"java.lang.Thread::afterSleep",
              "java.lang.Thread::sleepNanos",
              "java.lang.Thread::sleep"})
public final class ThreadSleepEvent extends MirrorEvent {
    @Label("Sleep Time")
    @Timespan(Timespan.NANOSECONDS)
    public long time;
}

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

    public static void yield() {
        if (currentThread() instanceof VirtualThread vthread) {
            vthread.tryYield();
        } else {
            yield0();
        }
    }

    private static native void yield0();

    /**
     * Called before sleeping to create a jdk.ThreadSleep event.
     */
    private static ThreadSleepEvent beforeSleep(long nanos) {
        try {
            ThreadSleepEvent event = new ThreadSleepEvent();
            if (event.isEnabled()) {
                event.time = nanos;
                event.begin();
                return event;
            }
        } catch (OutOfMemoryError e) {
            // ignore
        }
        return null;
    }


    /**
     * 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);
        }
    }

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

package jdk.internal.event;

/**
 * Event recording thread sleeping.
 */

public final class ThreadSleepEvent extends Event {
    public long time;
}

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

Field Type Description
time long: nanos Sleep Time

Examples 3
startTime long: millis
7524095583
time long: nanos
8000000
startTime long: millis
792492430750
time long: nanos
10000000
startTime long: millis
8171749667
time long: nanos
10000000

JavaErrorThrow

default profiling startTime duration 11 17 21 23 24

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

Category: Java Application

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

Configuration enabled stackTrace
default true true
profiling true true

Field Type Description
message string Message Consider contributing a description to jfreventcollector.
thrownClass Class Class Consider contributing a description to jfreventcollector.

Examples 3
message string
static Lorg/apache/spark/util/CollectionAccumulator;.<clinit>()V
startTime long: millis
869745810417
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
22
name string
java/lang
message string
Exception java.lang.ExceptionInInitializerError [in thread "main"]
startTime long: millis
3766716625
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/lang/ExceptionInInitializerError
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/lang
message string
'java.lang.Object java.lang.invoke.DirectMethodHandle$Holder.invokeInterface(java.lang.Object, java.lang.Object)'
startTime long: millis
548414625
thrownClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
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
21.0.1
name string
java/lang

FileForce

default profiling startTime duration 11 17 21 23 24

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/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.MirrorEvent;
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 MirrorEvent {

    // 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/MirrorEvents.java:

/**
 * This class registers all mirror events.
 */
final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);

src/java.base/share/classes/sun/nio/ch/SimpleAsynchronousFileChannelImpl.java:

                do {
                    n = nd.force(fdObj, metaData);
                } while ((n == IOStatus.INTERRUPTED) && isOpen());
            } finally {
                end(n >= 0);
            }
        } finally {
            threads.remove(ti);
        }
    }

    @Override
    public void force(boolean metaData) throws IOException {
        if (!FileForceEvent.enabled()) {
            implForce(metaData);
            return;
        }
        long start = FileForceEvent.timestamp();
        implForce(metaData);
        FileForceEvent.offer(start, path, metaData);
    }

    @Override
    <A> Future<FileLock> implLock(final long position,
                                  final long size,
                                  final boolean shared,
                                  final A attachment,
                                  final CompletionHandler<FileLock,? super A> handler)
    {
        if (shared && !reading)
            throw new NonReadableChannelException();

src/java.base/share/classes/sun/nio/ch/FileChannelImpl.java:

                } finally {
                    Blocker.end(attempted);
                }
            } while ((rv == IOStatus.INTERRUPTED) && isOpen());
        } finally {
            threads.remove(ti);
            endBlocking(rv > -1);
            assert IOStatus.check(rv);
        }
    }

    @Override
    public void force(boolean metaData) throws IOException {
        if (!FileForceEvent.enabled()) {
            implForce(metaData);
            return;
        }
        long start = FileForceEvent.timestamp();
        implForce(metaData);
        FileForceEvent.offer(start, path, metaData);
    }

    // Assume at first that the underlying kernel supports sendfile/equivalent;
    // set this to true if we find out later that it doesn't
    //
    private static volatile boolean transferToDirectNotSupported;

    // Assume at first that the underlying kernel supports copy_file_range/equivalent;
    // set this to true if we find out later that it doesn't
    //
    private static volatile boolean transferFromDirectNotSupported;

src/java.base/windows/classes/sun/nio/ch/WindowsAsynchronousFileChannelImpl.java:

    private void implForce(boolean metaData) throws IOException {
        try {
            begin();
            nd.force(fdObj, metaData);
        } finally {
            end();
        }
    }

    @Override
    public void force(boolean metaData) throws IOException {
        if (!FileForceEvent.enabled()) {
            implForce(metaData);
            return;
        }
        long start = FileForceEvent.timestamp();
        implForce(metaData);
        FileForceEvent.offer(start, path, metaData);
    }

    // -- file locking --

    /**
     * Task that initiates locking operation and handles completion result.
     */
    private class LockTask<A> implements Runnable, Iocp.ResultHandler {
        private final long position;
        private final FileLockImpl fli;
        private final PendingFuture<FileLock,A> result;

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

package jdk.internal.event;

/**
 * A JFR event for forced updates written to files.  This event is mirrored in
 * {@code jdk.jfr.events.FileForceEvent } where the event annotations are
 * provided.  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, boolean)} method
 * must be the same as the order of the fields.
 */
public class FileForceEvent extends Event {

    // THE ORDER OF THE FOLLOWING FIELDS IS IMPORTANT!
    // The order must match the argument order of the generated commit method.
    public String path;
    public boolean metaData;

    /**
     * Helper method to offer the data needed to potentially commit an event.
     * The duration of the operation is computed using the current
     * timestamp and the given start time.  If the duration is meets
     * or exceeds the configured value (determined by calling the generated method
     * {@link #shouldCommit(long)}), an event will be emitted by calling
     * {@link #commit(long, long, String, boolean)}.

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

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

SocketWrite

default profiling startTime duration 11 17 21 23 24

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")
public final class SocketWriteEvent extends MirrorEvent {

    @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:

    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadPinnedEvent", VirtualThreadPinnedEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);

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);
            } catch (InterruptedIOException e) {

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/sun/nio/ch/SocketChannelImpl.java:

        } finally {
            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;
    }

    /**
     * Writes a byte of out of band data.

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.

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

Field Type Description
host string Remote Host
address string Remote Address
port int Remote Port
bytesWritten long: bytes Bytes Written Number of bytes written to the socket

Examples 3
address string
127.0.0.1
bytesWritten long: bytes
34
host string
localhost
port int
56443
startTime long: millis
931139051417
address string
127.0.0.1
bytesWritten long: bytes
13
host string
localhost
port int
52652
startTime long: millis
41292561917
address string
127.0.0.1
bytesWritten long: bytes
50
host string
port int
52291
startTime long: millis
40820524708

VirtualThreadStart

startTime duration 19 21 23 24

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

Category: Java Application

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined 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")
@RemoveFields("duration")
public final class VirtualThreadStartEvent extends MirrorEvent {

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

}

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

    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadPinnedEvent", VirtualThreadPinnedEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
    };

    private static void register(String eventClassName, Class<? extends MirrorEvent> mirrorClass) {

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 {

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 static final VirtualThreadStartEvent EVENT = new VirtualThreadStartEvent();

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

    public long javaThreadId;
}

Configuration enabled stackTrace
default false true
profiling false true

Field Type Description
javaThreadId long Thread Id

Java Application Statistics

JavaThreadStatistics

default profiling startTime duration every chunk 11 17 21 23 24 graal vm

Category: Java Application / Statistics

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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_totalSize(totalPhysicalMemory);
  event.set_usedSize(totalPhysicalMemory - os::available_memory());
  event.commit();
}

TRACE_REQUEST_FUNC(SwapSpace) {
  EventSwapSpace event;
  event.set_totalSize(os::total_swap_space());
  event.set_freeSize(os::free_swap_space());
  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
default true 1000 ms
profiling true 1000 ms

Field Type Description
activeCount long Active Threads Number of live active threads including both daemon and non-daemon threads
daemonCount long Daemon Threads Number of live daemon threads
accumulatedCount long Accumulated Threads Number of threads created and also started since JVM start
peakCount long Peak Threads Peak live thread count since JVM start or when peak count was reset

Examples 3
accumulatedCount long
321
activeCount long
75
daemonCount long
74
peakCount long
75
startTime long: millis
49496714250
accumulatedCount long
2452
activeCount long
126
daemonCount long
117
peakCount long
314
startTime long: millis
926263948083
accumulatedCount long
53
activeCount long
42
daemonCount long
22
peakCount long
42
startTime long: millis
7582623958

ClassLoadingStatistics

default profiling startTime duration every chunk 11 17 21 23 24 graal vm

Category: Java Application / Statistics

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true 1000 ms
profiling true 1000 ms

Field Type Description
loadedClassCount long Loaded Class Count Number of classes loaded since JVM start
unloadedClassCount long Unloaded Class Count Number of classes unloaded since JVM start

Examples 3
loadedClassCount long
28776
startTime long: millis
80071262583
unloadedClassCount long
11848
loadedClassCount long
6943
startTime long: millis
31108945250
unloadedClassCount long
1589
loadedClassCount long
125965
startTime long: millis
908663813708
unloadedClassCount long
3325

ClassLoaderStatistics

default profiling startTime duration every chunk 11 17 21 23 24

Category: Java Application / Statistics

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

Field Type Description
classLoader ClassLoader Class Loader Consider contributing a description to jfreventcollector.
parentClassLoader ClassLoader Parent Class Loader Consider contributing a description to jfreventcollector.
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
5288
chunkSize ulong: bytes
6144
classCount long
2
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/codehaus/commons/compiler/util/reflect/ByteArrayClassLoader
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
22
name string
java/net
location string
null
name string
null
version string
null
name string
org/codehaus/commons/compiler/util/reflect
classLoaderData ulong: address
105553268069536
hiddenBlockSize ulong: bytes
0
hiddenChunkSize ulong: bytes
0
hiddenClassCount long
0
parentClassLoader ClassLoader
null
startTime long: millis
791772636958
blockSize ulong: bytes
1783552
chunkSize ulong: bytes
1789952
classCount long
187
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
classLoaderData ulong: address
105553176938688
hiddenBlockSize ulong: bytes
0
hiddenChunkSize ulong: bytes
0
hiddenClassCount long
0
parentClassLoader ClassLoader
name string
app
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
32
name string
jdk/internal/loader/ClassLoaders$AppClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
jdk/internal/loader
startTime long: millis
52082024292
blockSize ulong: bytes
0
chunkSize ulong: bytes
0
classCount long
0
classLoader ClassLoader
name string
platform
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
32
name string
jdk/internal/loader/ClassLoaders$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
21.0.1
name string
jdk/internal/loader
classLoaderData ulong: address
105553170253376
hiddenBlockSize ulong: bytes
0
hiddenChunkSize ulong: bytes
0
hiddenClassCount long
0
parentClassLoader ClassLoader
null
startTime long: millis
423166833

ThreadAllocationStatistics

default profiling startTime every chunk 11 17 21 23 24 graal vm

Category: Java Application / Statistics

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

Field Type Description
allocated ulong: bytes Allocated Approximate number of bytes allocated since thread start
thread Thread Thread Consider contributing a description to jfreventcollector.

Examples 3
allocated ulong: bytes
32
startTime long: millis
791772808042
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
map-output-dispatcher-6
javaThreadId long
1611
osName string
map-output-dispatcher-6
osThreadId long
64299
virtual boolean
false
allocated ulong: bytes
466400272
startTime long: millis
17899740292
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
ForkJoinPool.commonPool-worker-6
javaThreadId long
36
osName string
ForkJoinPool.commonPool-worker-6
osThreadId long
43267
virtual boolean
false
allocated ulong: bytes
32139592
startTime long: millis
14906032000
thread Thread
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
UCT-akka.actor.default-dispatcher-12
javaThreadId long
123
osName string
UCT-akka.actor.default-dispatcher-12
osThreadId long
47111
virtual boolean
false

FinalizerStatistics

default profiling startTime end of every chunk 18 21 23 24

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
default true endChunk
profiling true endChunk

Field Type Description
finalizableClass Class Class Overriding Finalize
codeSource Symbol Code Source URL from where the class was loaded
objects ulong Finalizable Objects on Heap Number of objects on heap that can be finalized
totalFinalizersRun ulong Finalizers Run Total number of finalizers run since JVM start

Examples 3
codeSource Symbol
file://[...]/code/experiments/jfreventcollector/harness-124447-3147988932466435938/twitter-finagle/lib/netty-buffer-4.1.72.Final.jar
finalizableClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hidden boolean
false
modifiers int
48
name string
io/netty/buffer/PoolArena$HeapArena
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/buffer
objects ulong
16
startTime long: millis
93710152708
totalFinalizersRun ulong
0
codeSource Symbol
file://[...]/code/experiments/jfreventcollector/harness-141003-16632656921422798882/apache-spark/lib/netty-buffer-4.1.99.Final.jar
finalizableClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/net
hidden boolean
false
modifiers int
24
name string
io/netty/buffer/PoolArena$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
22
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/buffer
objects ulong
32
startTime long: millis
824402883208
totalFinalizersRun ulong
0
codeSource Symbol
file://[...]/code/experiments/jfreventcollector/harness-124622-12434569844652140370/twitter-finagle/lib/netty-buffer-4.1.72.Final.jar
finalizableClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
hidden boolean
false
modifiers int
48
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
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/buffer
objects ulong
16
startTime long: millis
52070349292
totalFinalizersRun ulong
0

DeprecatedInvocation

default profiling startTime stackTrace 22 23 24

Category: Java Application / Statistics

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

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
default true forRemoval true
profiling 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

Examples 1
forRemoval boolean
true
invocationTime Ticks
388237030375
method Method
descriptor string
(Ljava/security/PrivilegedAction;)Ljava/lang/Object;
hidden boolean
false
modifiers int
9
name string
doPrivileged
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/security/AccessController
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/security
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
46
lineNumber int
186
method Method
descriptor string
()Lio/netty/channel/nio/NioEventLoop$SelectorTuple;
hidden boolean
false
modifiers int
2
name string
openSelector
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
22
name string
java/net
hidden boolean
false
modifiers int
17
name string
io/netty/channel/nio/NioEventLoop
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
22
name string
java/net
location string
null
name string
null
version string
null
name string
io/netty/channel/nio
type FrameType
Interpreted
truncated boolean
true
startTime long: millis
798537852583

ExceptionStatistics

default profiling startTime duration 11 17 21 23 24

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.internal.MirrorEvent;
import jdk.jfr.internal.RemoveFields;
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")
@RemoveFields({"duration", "eventThread", "stackTrace"})
public final class ExceptionStatisticsEvent extends MirrorEvent {

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

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

        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadPinnedEvent", VirtualThreadPinnedEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
    };

    private static void register(String eventClassName, Class<? extends MirrorEvent> mirrorClass) {
        mirrorLookup.put(eventClassName, mirrorClass);
    }

    static Class<? extends MirrorEvent> find(Class<? extends jdk.internal.event.Event> eventClass) {
        return find(Utils.isJDKClass(eventClass), eventClass.getName());
    }

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
default true 1000 ms
profiling true 1000 ms

Field Type Description
throwables long Exceptions Created

Examples 3
startTime long: millis
833403711958
throwables long
2319216
startTime long: millis
61736881042
throwables long
202110
startTime long: millis
92191504875
throwables long
340156

DirectBufferStatistics

default profiling startTime duration stackTrace 15 17 21 23 24

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/JDKEvents.java:

        jdk.internal.event.SecurityPropertyModificationEvent.class,
        jdk.internal.event.SecurityProviderServiceEvent.class,
        jdk.internal.event.SerializationMisdeclarationEvent.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,
    };

    private static final Runnable emitExceptionStatistics = JDKEvents::emitExceptionStatistics;
    private static final Runnable emitDirectBufferStatistics = JDKEvents::emitDirectBufferStatistics;
    private static final Runnable emitContainerConfiguration = JDKEvents::emitContainerConfiguration;
    private static final Runnable emitContainerCPUUsage = JDKEvents::emitContainerCPUUsage;
    private static final Runnable emitContainerCPUThrottling = JDKEvents::emitContainerCPUThrottling;
    private static final Runnable emitContainerMemoryUsage = JDKEvents::emitContainerMemoryUsage;
    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();
                JFRTracing.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/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
default true 5 s
profiling true 5 s

Examples 3
startTime long: millis
879137650167
stackTrace StackTrace
null
startTime long: millis
58104091583
stackTrace StackTrace
null
startTime long: millis
30104250083

Java Development Kit

VirtualThreadSubmitFailed

default profiling startTime duration 19 21 23 24

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/internal/MirrorEvents.java:

        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadPinnedEvent", VirtualThreadPinnedEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
    };

    private static void register(String eventClassName, Class<? extends MirrorEvent> mirrorClass) {
        mirrorLookup.put(eventClassName, mirrorClass);
    }

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")
@RemoveFields("duration")
public final class VirtualThreadSubmitFailedEvent extends MirrorEvent {

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

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

}

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

        if (scheduler == DEFAULT_SCHEDULER && currentCarrierThread() instanceof CarrierThread ct) {
            try {
                ct.getPool().externalSubmit(ForkJoinTask.adapt(runContinuation));
            } catch (RejectedExecutionException ree) {
                submitFailed(ree);
                throw ree;
            }
        } else {
            submitRunContinuation(scheduler, false);
        }
    }

    /**
     * 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) {

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;
}

Configuration enabled stackTrace
default true true
profiling true true

Field Type Description
javaThreadId long Thread Id
exceptionMessage string Exception Message Consider contributing a description to jfreventcollector.

SecurityProviderService

startTime duration 11 17 21 23 24

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/internal/MirrorEvents.java:

 * This class registers all mirror events.
 */
final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadPinnedEvent", VirtualThreadPinnedEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);

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")
@RemoveFields("duration")
@StackFilter({"java.security.Provider::getService"})
public final class SecurityProviderServiceEvent extends MirrorEvent {
    @Label("Type of Service")
    public String type;

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

    @Label("Security Provider")
    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

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 static final 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;
}

Configuration enabled stackTrace
default false true
profiling false true

Field Type Description
type string Type of Service
algorithm string Algorithm Name
provider string Security Provider

Examples 3
algorithm string
NativePRNG
provider string
SUN
startTime long: millis
463012625
type string
SecureRandom
algorithm string
NativePRNG
provider string
SUN
startTime long: millis
537709583
type string
SecureRandom
algorithm string
SHA
provider string
SUN
startTime long: millis
869702513875
type string
MessageDigest

SecurityPropertyModification

startTime duration 11 17 21 23 24

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/internal/MirrorEvents.java:

/**
 * This class registers all mirror events.
 */
final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadPinnedEvent", VirtualThreadPinnedEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);

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")
@RemoveFields("duration")
@StackFilter({"java.security.Security::setProperty"})
public final class SecurityPropertyModificationEvent extends MirrorEvent {
    @Label("Key")
    public String key;

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

src/java.base/share/classes/java/security/Security.java:

     * @throws  IllegalArgumentException if key is reserved and cannot be
     *          used as a Security property name. Reserved keys are:
     *          "include".
     *
     * @see #getProperty
     * @see java.security.SecurityPermission
     */
    public static void setProperty(String key, String datum) {
        SecPropLoader.checkReservedKey(key);
        check("setProperty." + key);
        props.put(key, datum);
        invalidateSMCache(key);  /* See below. */

        SecurityPropertyModificationEvent spe = new SecurityPropertyModificationEvent();
        // following is a no-op if event is disabled
        spe.key = key;
        spe.value = datum;
        spe.commit();

        if (EventHelper.isLoggingSecurity()) {
            EventHelper.logSecurityPropertyEvent(key, datum);
        }
    }

    /*

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

package jdk.internal.event;

/**
 * Event details relating to the modification of a Security property.
 */

public final class SecurityPropertyModificationEvent extends Event {
    public String key;
    public String value;
}

Configuration enabled stackTrace
default false true
profiling false true

Field Type Description
key string Key Consider contributing a description to jfreventcollector.
value string Value Consider contributing a description to jfreventcollector.

X509Certificate

startTime duration 11 17 21 23 24

Source src/jdk.jfr/share/classes/jdk/jfr/events/X509CertificateEvent.java

Category: Java Development Kit / Security

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

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")
@RemoveFields("duration")
public final class X509CertificateEvent extends MirrorEvent {
    @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:

        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadPinnedEvent", VirtualThreadPinnedEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
    };

    private static void register(String eventClassName, Class<? extends MirrorEvent> mirrorClass) {
        mirrorLookup.put(eventClassName, mirrorClass);
    }

    static Class<? extends MirrorEvent> find(Class<? extends jdk.internal.event.Event> eventClass) {

src/java.base/share/classes/sun/security/jca/JCAUtil.java:

        SecureRandom result = def;
        if (result == null) {
            synchronized (JCAUtil.class) {
                result = def;
                if (result == null) {
                    def = result = new SecureRandom();
                }
            }
        }
        return result;
    }

    public static void tryCommitCertEvent(Certificate cert) {
        if ((X509CertificateEvent.isTurnedOn() || EventHelper.isLoggingSecurity()) &&
                (cert instanceof X509Certificate x509)) {
            PublicKey pKey = x509.getPublicKey();
            String algId = x509.getSigAlgName();
            String serNum = Debug.toString(x509.getSerialNumber());
            String subject = x509.getSubjectX500Principal().toString();
            String issuer = x509.getIssuerX500Principal().toString();
            String keyType = pKey.getAlgorithm();
            int length = KeyUtil.getKeySize(pKey);
            int hashCode = x509.hashCode();
            long 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();
            }

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;

Configuration enabled stackTrace
default false true
profiling false true

Field Type Description
algorithm string Signature Algorithm
serialNumber string Serial Number Consider contributing a description to jfreventcollector.
subject string Subject Consider contributing a description to jfreventcollector.
issuer string Issuer Consider contributing a description to jfreventcollector.
keyType string Key Type Consider contributing a description to jfreventcollector.
keyLength int Key Length
certificateId ulong: certificateId Certificate Id
validFrom long: epochmillis Valid From
validUntil long: epochmillis Valid Until

Examples 1
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
46101f71
startTime long: millis
869989482917
subject string
CN=Unknown, OU=Unknown, O=Unknown, L=Unknown, ST=Unknown, C=Unknown
validFrom long: epochmillis
1175461745000
validUntil long: epochmillis
4329061745000

Deserialization

startTime duration 11 17 21 23 24

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

Category: Java Development Kit / Serialization

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

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")
@RemoveFields("duration")
public final class DeserializationEvent extends MirrorEvent {

    @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:

/**
 * This class registers all mirror events.
 */
final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);

src/java.base/share/classes/java/io/ObjectInputStream.java:

        ObjectInputFilter next = Config.getSerialFilterFactory()
                .apply(serialFilter, filter);
        if (serialFilter != null && next == null) {
            throw new IllegalStateException("filter can not be replaced with null filter");
        }
        serialFilter = next;
    }

    /**
     * Invokes the deserialization filter if non-null.
     *
     * If the filter rejects or an exception is thrown, throws InvalidClassException.
     *
     * Logs and/or commits a {@code DeserializationEvent}, if configured.
     *
     * @param clazz the class; may be null
     * @param arrayLength the array length requested; use {@code -1} if not creating an array
     * @throws InvalidClassException if it rejected by the filter or
     *        a {@link RuntimeException} is thrown
     */
    private void filterCheck(Class<?> clazz, int arrayLength)
            throws InvalidClassException {
        // Info about the stream is not available if overridden by subclass, return 0
        long bytesRead = (bin == null) ? 0 : bin.getBytesRead();
        RuntimeException ex = null;

src/java.base/share/classes/java/io/ObjectInputStream.java:

                status = ObjectInputFilter.Status.REJECTED;
                ex = e;
            }
            if (Logging.filterLogger != null) {
                // Debug logging of filter checks that fail; Tracing for those that succeed
                Logging.filterLogger.log(status == null || status == ObjectInputFilter.Status.REJECTED
                                ? Logger.Level.DEBUG
                                : Logger.Level.TRACE,
                        "ObjectInputFilter {0}: {1}, array length: {2}, nRefs: {3}, depth: {4}, bytes: {5}, ex: {6}",
                        status, clazz, arrayLength, totalObjectRefs, depth, bytesRead,
                        Objects.toString(ex, "n/a"));
            }
        }
        DeserializationEvent event = new DeserializationEvent();
        if (event.shouldCommit()) {
            event.filterConfigured = serialFilter != null;
            event.filterStatus = status != null ? status.name() : null;
            event.type = clazz;
            event.arrayLength = arrayLength;
            event.objectReferences = totalObjectRefs;
            event.depth = depth;
            event.bytesRead = bytesRead;
            event.exceptionType = ex != null ? ex.getClass() : null;
            event.exceptionMessage = ex != null ? ex.getMessage() : null;
            event.commit();

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

package jdk.internal.event;

/**
 * Event details relating to deserialization.
 */

public final class DeserializationEvent extends Event {
    public boolean filterConfigured;
    public String filterStatus;
    public Class<?> type;
    public int arrayLength;
    public long objectReferences;
    public long depth;
    public long bytesRead;
    public Class<?> exceptionType;
    public String exceptionMessage;
}

Configuration enabled stackTrace
default false true
profiling false true

Field Type Description
filterConfigured boolean Filter Configured
filterStatus string Filter Status Consider contributing a description to jfreventcollector.
type Class Type Consider contributing a description to jfreventcollector.
arrayLength int Array Length
objectReferences long Object References
depth long Depth
bytesRead long Bytes Read
exceptionType Class Exception Type Consider contributing a description to jfreventcollector.
exceptionMessage string Exception Message Consider contributing a description to jfreventcollector.

Examples 1
arrayLength int
10
bytesRead long
98053
depth long
3
exceptionMessage string
null
exceptionType Class
null
filterConfigured boolean
false
filterStatus string
null
objectReferences long
1967
startTime long: millis
791550348833
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[F
package Package
null

TLSHandshake

startTime duration 11 17 21 23 24

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")
@RemoveFields("duration")
@StackFilter("sun.security.ssl.Finished::recordEvent")
public final class TLSHandshakeEvent extends MirrorEvent {
    @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:

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadPinnedEvent", VirtualThreadPinnedEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
    };

src/java.base/share/classes/sun/security/ssl/Finished.java:

                shc.conContext.finishHandshake();
            }
            recordEvent(shc.conContext.conSession);

            //
            // produce
            if (SSLConfiguration.serverNewSessionTicketCount > 0) {
                NewSessionTicket.t13PosthandshakeProducer.produce(shc);
            }
        }
    }

    private static void recordEvent(SSLSessionImpl session) {
        TLSHandshakeEvent event = new TLSHandshakeEvent();
        if (event.shouldCommit() || EventHelper.isLoggingSecurity()) {
            int hash = 0;
            try {
                // use hash code for Id
                hash = session
                        .getCertificateChain()[0]
                        .hashCode();
            } catch (SSLPeerUnverifiedException e) {
                 // not verified msg
            }
            long peerCertificateId = Integer.toUnsignedLong(hash);

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;
}

Configuration enabled stackTrace
default false true
profiling false true

Field Type Description
peerHost string Peer Host Consider contributing a description to jfreventcollector.
peerPort int Peer Port
protocolVersion string Protocol Version Consider contributing a description to jfreventcollector.
cipherSuite string Cipher Suite Consider contributing a description to jfreventcollector.
certificateId ulong: certificateId Certificate Id Peer Certificate Id

X509Validation

startTime duration 11 17 21 23 24

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")
@RemoveFields("duration")
public final class X509ValidationEvent extends MirrorEvent {
    @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:

        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadPinnedEvent", VirtualThreadPinnedEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);
        register("jdk.internal.event.ExceptionStatisticsEvent", ExceptionStatisticsEvent.class);
        register("jdk.internal.event.ExceptionThrownEvent", ExceptionThrownEvent.class);
    };

    private static void register(String eventClassName, Class<? extends MirrorEvent> mirrorClass) {
        mirrorLookup.put(eventClassName, mirrorClass);
    }

    static Class<? extends MirrorEvent> find(Class<? extends jdk.internal.event.Event> eventClass) {
        return find(Utils.isJDKClass(eventClass), eventClass.getName());

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

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;
}

Configuration enabled stackTrace
default false true
profiling 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

SerializationMisdeclaration

profiling startTime duration 23 24

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

Category: Java Development Kit / Serialization

Methods and fields misdeclarations. The checks are usually performed just once per serializable class, the first time it is used by serialization. Under high memory pressure, a class might be re-checked again.

Code Context

The event is likely defined 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/SerializationMisdeclarationEvent.java:

@Name(Type.EVENT_NAME_PREFIX + "SerializationMisdeclaration")
@Label("Serialization Misdeclaration")
@Category({"Java Development Kit", "Serialization"})
@Description("Methods and fields misdeclarations." +
        " The checks are usually performed just once per serializable class," +
        " the first time it is used by serialization." +
        " Under high memory pressure, a class might be re-checked again.")
@RemoveFields({"duration", "stackTrace", "eventThread"})
public final class SerializationMisdeclarationEvent extends MirrorEvent {

    @Label("Misdeclared Class")
    public Class<?> misdeclaredClass;

    @Label("Message")
    public String message;

}

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

 */
final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadPinnedEvent", VirtualThreadPinnedEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);
        register("jdk.internal.event.X509CertificateEvent", X509CertificateEvent.class);
        register("jdk.internal.event.X509ValidationEvent", X509ValidationEvent.class);
        register("jdk.internal.event.ErrorThrownEvent", ErrorThrownEvent.class);

src/java.base/share/classes/java/io/ObjectStreamClass.java:

        if (isRecord && canonicalCtr == null) {
            deserializeEx = new ExceptionInfo(name, "record canonical constructor not found");
        } else {
            for (int i = 0; i < fields.length; i++) {
                if (fields[i].getField() == null) {
                    defaultSerializeEx = new ExceptionInfo(
                        name, "unmatched serializable field(s) declared");
                }
            }
        }
        initialized = true;

        if (SerializationMisdeclarationEvent.enabled() && serializable) {
            SerializationMisdeclarationChecker.checkMisdeclarations(cl);
        }
    }

    /**
     * Creates blank class descriptor which should be initialized via a
     * subsequent call to initProxy(), initNonProxy() or readNonProxy().
     */
    ObjectStreamClass() {
    }

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

package jdk.internal.event;

/**
 * A JFR event for serialization misdeclarations.
 * This event is mirrored in {@code jdk.jfr.events.SerializationMisdeclarationEvent}
 * 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,Class,String)}
 * method must be the same as the order of the fields.
 */
public class SerializationMisdeclarationEvent extends Event {

    public Class<?> misdeclaredClass;
    public String message;

    /**
     * Commit a serialization misdeclaration event.
     * The implementation of this method is generated automatically if jfr is enabled.
     * The order of the fields must be the same as the parameters in this method.
     * {@code commit(long,Class,String)}
     *
     * @param start             timestamp of the start of the operation
     * @param misdeclaredClass  the affected class
     * @param message           the specific event message

Configuration enabled
default false
profiling true

Field Type Description
misdeclaredClass Class Misdeclared Class Consider contributing a description to jfreventcollector.
message string Message Consider contributing a description to jfreventcollector.

InitialSecurityProperty

default profiling startTime duration stackTrace 17 21 23 24

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/JDKEvents.java:

        jdk.internal.event.SecurityProviderServiceEvent.class,
        jdk.internal.event.SerializationMisdeclarationEvent.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,
    };

    private static final Runnable emitExceptionStatistics = JDKEvents::emitExceptionStatistics;
    private static final Runnable emitDirectBufferStatistics = JDKEvents::emitDirectBufferStatistics;
    private static final Runnable emitContainerConfiguration = JDKEvents::emitContainerConfiguration;
    private static final Runnable emitContainerCPUUsage = JDKEvents::emitContainerCPUUsage;
    private static final Runnable emitContainerCPUThrottling = JDKEvents::emitContainerCPUThrottling;
    private static final Runnable emitContainerMemoryUsage = JDKEvents::emitContainerMemoryUsage;
    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();
                JFRTracing.enable();
                initializationTriggered = true;
            }
        } catch (Exception e) {
            Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Could not initialize JDK events. " + e.getMessage());
        }
    }

    private static void initializeContainerEvents() {

src/jdk.jfr/share/classes/jdk/jfr/internal/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
default true beginChunk
profiling true beginChunk

Field Type Description
key string Key Consider contributing a description to jfreventcollector.
value string Value Consider contributing a description to jfreventcollector.

Examples 3
key string
security.provider.5
stackTrace StackTrace
null
startTime long: millis
379246833
value string
SunJCE
key string
sun.security.krb5.maxReferrals
startTime long: millis
798811468875
value string
5
key string
jceks.key.serialFilter
stackTrace StackTrace
null
startTime long: millis
437366667
value string
java.base/java.lang.Enum;java.base/java.security.KeyRep;java.base/java.security.KeyRep$Type;java.base/javax.crypto.spec.SecretKeySpec;!*

Operating System

OSInformation

default profiling startTime duration end of every chunk 11 17 21 23 24 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_version = nullptr;
  JfrOSInterface::os_version(&os_version);
  EventOSInformation event;
  event.set_osVersion(os_version);
  event.commit();
}

TRACE_REQUEST_FUNC(VirtualizationInformation) {
  EventVirtualizationInformation event;
  event.set_name(JfrOSInterface::virtualization_name());
  event.commit();
}

TRACE_REQUEST_FUNC(ModuleRequire) {

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
osVersion string OS Version

Examples 3
osVersion string
uname: Darwin 24.0.0 Darwin Kernel Version 24.0.0: Mon Aug 12 20:49:48 PDT 2024; root:xnu-11215.1.10~2/RELEASE_ARM64_T8103 arm64
startTime long: millis
904000710208
osVersion string
uname: Darwin 23.2.0 Darwin Kernel Version 23.2.0: Wed Nov 15 21:53:34 PST 2023; root:xnu-10002.61.3~2/RELEASE_ARM64_T8103 arm64
startTime long: millis
52080830500
osVersion string
uname: Darwin 23.2.0 Darwin Kernel Version 23.2.0: Wed Nov 15 21:53:34 PST 2023; root:xnu-10002.61.3~2/RELEASE_ARM64_T8103 arm64
startTime long: millis
60343485667

VirtualizationInformation

default profiling startTime duration end of every chunk 11 17 21 23 24

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_version = nullptr;
  JfrOSInterface::os_version(&os_version);
  EventOSInformation event;
  event.set_osVersion(os_version);
  event.commit();
}

TRACE_REQUEST_FUNC(VirtualizationInformation) {
  EventVirtualizationInformation event;
  event.set_name(JfrOSInterface::virtualization_name());
  event.commit();
}

TRACE_REQUEST_FUNC(ModuleRequire) {
  JfrModuleEvent::generate_module_dependency_events();
}

TRACE_REQUEST_FUNC(ModuleExport) {
  JfrModuleEvent::generate_module_export_events();
}

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
name string Name

Examples 3
name string
No virtualization detected
startTime long: millis
96710863583
name string
No virtualization detected
startTime long: millis
17889808458
name string
No virtualization detected
startTime long: millis
857424887333

InitialEnvironmentVariable

default profiling startTime end of every chunk 11 17 21 23 24 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
default true beginChunk
profiling true beginChunk

Field Type Description
key string Key
value string Value

Examples 3
key string
POMCHECKER_HOME
startTime long: millis
798650496458
value string
[...]/.sdkman/candidates/pomchecker/current
key string
LANG
startTime long: millis
422640458
value string
en_US.UTF-8
key string
ZSH
startTime long: millis
15755091500
value string
[...]/.oh-my-zsh

SystemProcess

default profiling startTime duration end of every chunk 11 17 21 23 24

Category: Operating System

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

Field Type Description
pid string Process Identifier
commandLine string Command Line

Examples 3
commandLine string
/usr/sbin/distnoted
pid string
651
startTime long: millis
16726490792
commandLine string
/Library/Application Support/NexthinkVersions/24.6.1.27_1/nxtcoordinator
pid string
609
startTime long: millis
795726520208
commandLine string
/System/Library/PrivateFrameworks/ApplePushService.framework/apsd
pid string
575
startTime long: millis
14787855958

CPUInformation

default profiling startTime duration end of every chunk 11 17 21 23 24

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
default true beginChunk
profiling true beginChunk

Field Type Description
cpu string Type
description string Description
sockets uint Sockets
cores uint Cores
hwThreads uint Hardware Threads

Examples 3
cores uint
8
cpu string
AArch64
description string
AArch64 0x61:0x0:0x1b588bb3:0, fp, asimd, aes, pmull, sha1, sha256, crc32, lse, sha3, sha512
hwThreads uint
8
sockets uint
8
startTime long: millis
84413966333
cores uint
8
cpu string
AArch64
description string
AArch64 0x61:0x0:0x1b588bb3:0, fp, asimd, aes, pmull, sha1, sha256, crc32, lse, sha3, sha512
hwThreads uint
8
sockets uint
8
startTime long: millis
917977184833
cores uint
8
cpu string
AArch64
description string
AArch64 0x61:0x0:0x1b588bb3:0, fp, asimd, aes, pmull, sha1, sha256, crc32, lse, sha3, sha512
hwThreads uint
8
sockets uint
8
startTime long: millis
78940176625

CPUTimeStampCounter

default profiling startTime duration end of every chunk 11 17 21 23 24

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
default true beginChunk
profiling true beginChunk

Field Type Description
fastTimeEnabled boolean Fast Time
fastTimeAutoEnabled boolean Trusted Platform
osFrequency long: hertz OS Frequency
fastTimeFrequency long: hertz Fast Time Frequency

Examples 3
fastTimeAutoEnabled boolean
false
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
75961252333
fastTimeAutoEnabled boolean
false
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
839577541333
fastTimeAutoEnabled boolean
false
fastTimeEnabled boolean
false
fastTimeFrequency long: hertz
1000000000
osFrequency long: hertz
1000000000
startTime long: millis
78940177167

CPULoad

default profiling startTime duration every chunk 11 17 21 23 24

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
default true 1000 ms
profiling true 1000 ms

Field Type Description
jvmUser float: percentage JVM User
jvmSystem float: percentage JVM System
machineTotal float: percentage Machine Total

Examples 3
jvmSystem float: percentage
0.0010318022
jvmUser float: percentage
0.005607464
machineTotal float: percentage
0.98376626
startTime long: millis
884659123375
jvmSystem float: percentage
6.6612905E-4
jvmUser float: percentage
0.01064864
machineTotal float: percentage
0.93257
startTime long: millis
7613770458
jvmSystem float: percentage
9.003277E-5
jvmUser float: percentage
0.0028848457
machineTotal float: percentage
0.7691327
startTime long: millis
66184971292

ThreadCPULoad

default profiling startTime duration eventThread every chunk 11 17 21 23 24 graal vm

Category: Operating System / Processor

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

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

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

int JfrThreadCPULoadEvent::get_processor_count() {
  int cur_processor_count = os::active_processor_count();
  int last_processor_count = _last_active_processor_count;
  _last_active_processor_count = cur_processor_count;

  // If the number of processors decreases, we don't know at what point during
  // the sample interval this happened, so use the largest number to try
  // to avoid percentages above 100%
  return MAX2(cur_processor_count, last_processor_count);
}

// Returns false if the thread has not been scheduled since the last call to updateEvent
// (i.e. the delta for both system and user time is 0 milliseconds)
bool JfrThreadCPULoadEvent::update_event(EventThreadCPULoad& event, JavaThread* thread, jlong cur_wallclock_time, int processor_count) {
  JfrThreadLocal* const tl = thread->jfr_thread_local();

  jlong cur_cpu_time = os::thread_cpu_time(thread, true);
  jlong prev_cpu_time = tl->get_cpu_time();

  jlong prev_wallclock_time = tl->get_wallclock_time();
  tl->set_wallclock_time(cur_wallclock_time);

  // Threshold of 1 ms
  if (cur_cpu_time - prev_cpu_time < 1 * NANOSECS_PER_MILLISEC) {
    return false;

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

void JfrThreadCPULoadEvent::send_events() {
  Thread* periodic_thread = Thread::current();
  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();
    }
  }
}

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

Configuration enabled period
default true 10 s
profiling true 10 s

Field Type Description
user float: percentage User Mode CPU Load User mode thread CPU load
system float: percentage System Mode CPU Load System mode thread CPU load

Examples 3
startTime long: millis
6536868208
system float: percentage
0.0047701197
user float: percentage
0.0075395685
startTime long: millis
11595339875
system float: percentage
4.5879654E-4
user float: percentage
0.005210238
startTime long: millis
798811731500
system float: percentage
2.4332287E-6
user float: percentage
1.3262093E-6

ThreadContextSwitchRate

default profiling startTime duration every chunk 11 17 21 23 24

Category: Operating System / Processor

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true 10 s
profiling true 10 s

Field Type Description
switchRate float: hertz Switch Rate Number of context switches per second

Examples 3
startTime long: millis
67196140417
switchRate float: hertz
21043.934
startTime long: millis
73569042667
switchRate float: hertz
8249.412
startTime long: millis
895277721042
switchRate float: hertz
13638.212

NetworkUtilization

default profiling startTime every chunk 11 17 21 23 24

Category: Operating System / Network

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Code Context

The event is likely defined and utilized 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
default true 5 s
profiling true 5 s

Field Type Description
networkInterface NetworkInterfaceName Network Interface Network Interface Name
readRate long: bits-per-second Read Rate Number of incoming bits per second
writeRate long: bits-per-second Write Rate Number of outgoing bits per second

Examples 3
networkInterface NetworkInterfaceName
en0
readRate long: bits-per-second
3845016
startTime long: millis
88354783958
writeRate long: bits-per-second
2522560
networkInterface NetworkInterfaceName
lo0
readRate long: bits-per-second
7504
startTime long: millis
911682882875
writeRate long: bits-per-second
7504
networkInterface NetworkInterfaceName
lo0
readRate long: bits-per-second
22240608
startTime long: millis
37414570708
writeRate long: bits-per-second
22240608

PhysicalMemory

default profiling startTime duration every chunk 11 17 21 23 24 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(SwapSpace) {
  EventSwapSpace event;
  event.set_totalSize(os::total_swap_space());
  event.set_freeSize(os::free_swap_space());
  event.commit();
}

Configuration enabled period
default true everyChunk
profiling true everyChunk

Field Type Description
totalSize ulong: bytes Total Size Total amount of physical memory available to OS
usedSize ulong: bytes Used Size Total amount of physical memory in use

Examples 3
startTime long: millis
805717376542
totalSize ulong: bytes
17179869184
usedSize ulong: bytes
17110302720
startTime long: millis
75086819833
totalSize ulong: bytes
17179869184
usedSize ulong: bytes
17063084032
startTime long: millis
40030993708
totalSize ulong: bytes
17179869184
usedSize ulong: bytes
17094295552

SwapSpace

default profiling startTime duration every chunk 23 24

Category: Operating System / Memory

OS Swap Space

Code Context

The event is likely defined and utilized 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(SwapSpace) {
  EventSwapSpace event;
  event.set_totalSize(os::total_swap_space());
  event.set_freeSize(os::free_swap_space());
  event.commit();
}

TRACE_REQUEST_FUNC(JavaThreadStatistics) {
  EventJavaThreadStatistics event;
  event.set_activeCount(ThreadService::get_live_thread_count());
  event.set_daemonCount(ThreadService::get_daemon_thread_count());
  event.set_accumulatedCount(ThreadService::get_total_thread_count());
  event.set_peakCount(ThreadService::get_peak_thread_count());

Configuration enabled period
default true everyChunk
profiling true everyChunk

Field Type Description
totalSize long: bytes Total Size Total swap space available to the OS
freeSize long: bytes Free Size Free swap space

ProcessStart

default profiling startTime duration 15 17 21 23 24

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

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

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/internal/MirrorEvents.java:

/**
 * This class registers all mirror events.
 */
final class MirrorEvents {
    private static final Map<String, Class<? extends MirrorEvent>> mirrorLookup = new ConcurrentHashMap<>();

    // Add mirror event mapping here. See MirrorEvent class for details.
    static {
        register("jdk.internal.event.DeserializationEvent", DeserializationEvent.class);
        register("jdk.internal.event.FileForceEvent", FileForceEvent.class);
        register("jdk.internal.event.FileReadEvent", FileReadEvent.class);
        register("jdk.internal.event.FileWriteEvent", FileWriteEvent.class);
        register("jdk.internal.event.ProcessStartEvent", ProcessStartEvent.class);
        register("jdk.internal.event.SecurityPropertyModificationEvent", SecurityPropertyModificationEvent.class);
        register("jdk.internal.event.SecurityProviderServiceEvent", SecurityProviderServiceEvent.class);
        register("jdk.internal.event.SerializationMisdeclarationEvent", SerializationMisdeclarationEvent.class);
        register("jdk.internal.event.SocketReadEvent", SocketReadEvent.class);
        register("jdk.internal.event.SocketWriteEvent", SocketWriteEvent.class);
        register("jdk.internal.event.ThreadSleepEvent", ThreadSleepEvent.class);
        register("jdk.internal.event.TLSHandshakeEvent", TLSHandshakeEvent.class);
        register("jdk.internal.event.VirtualThreadStartEvent", VirtualThreadStartEvent.class);
        register("jdk.internal.event.VirtualThreadEndEvent", VirtualThreadEndEvent.class);
        register("jdk.internal.event.VirtualThreadPinnedEvent", VirtualThreadPinnedEvent.class);
        register("jdk.internal.event.VirtualThreadSubmitFailedEvent", VirtualThreadSubmitFailedEvent.class);

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

@Category({"Operating System"})
@Label("Process Start")
@Name("jdk.ProcessStart")
@Description("Operating system process started")
@RemoveFields("duration")
@StackFilter({"java.lang.ProcessBuilder", "java.lang.Runtime::exec"})
public final class ProcessStartEvent extends MirrorEvent {
    @Label("Process Id")
    public long pid;

    @Label("Directory")
    public String directory;

    @Label("Command")
    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");
            }

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;
}

Configuration enabled stackTrace
default true true
profiling true true

Field Type Description
pid long Process Id
directory string Directory Consider contributing a description to jfreventcollector.
command string Command Consider contributing a description to jfreventcollector.

Examples 1
command string
rm -rf [...]/code/experiments/jfreventcollector/harness-141003-16632656921422798882/apache-spark/als/spark-22d93730-23e3-46bf-b3cc-0c2cd596c37f
directory string
null
pid long
58054
startTime long: millis
940914394625

ContainerCPUUsage

default profiling startTime duration stackTrace 17 21 23 24

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/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/JDKEvents.java:

            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.hostTotalSwapMemory = JVM.hostTotalSwapMemory();
            t.commit();
        }
    }

    private static void emitContainerCPUUsage() {
        if (containerMetrics != null) {
            ContainerCPUUsageEvent event = new ContainerCPUUsageEvent();

            event.cpuTime = containerMetrics.getCpuUsage();
            event.cpuSystemTime = containerMetrics.getCpuSystemUsage();
            event.cpuUserTime = containerMetrics.getCpuUserUsage();
            event.commit();
        }
    }
    private static void emitContainerMemoryUsage() {
        if (containerMetrics != null) {
            ContainerMemoryUsageEvent event = new ContainerMemoryUsageEvent();

Configuration enabled period
default true 30 s
profiling true 30 s

Field Type Description
cpuTime long: nanos CPU Time Aggregate time consumed by all tasks in the container
cpuUserTime long: nanos CPU User Time Aggregate user time consumed by all tasks in the container
cpuSystemTime long: nanos CPU System Time Aggregate system time consumed by all tasks in the container

ContainerIOUsage

default profiling startTime duration stackTrace 17 21 23 24

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/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/JDKEvents.java:

    private static void emitContainerMemoryUsage() {
        if (containerMetrics != null) {
            ContainerMemoryUsageEvent event = new ContainerMemoryUsageEvent();

            event.memoryFailCount = containerMetrics.getMemoryFailCount();
            event.memoryUsage = containerMetrics.getMemoryUsage();
            event.swapMemoryUsage = containerMetrics.getMemoryAndSwapUsage();
            event.commit();
        }
    }

    private static void emitContainerIOUsage() {
        if (containerMetrics != null) {
            ContainerIOUsageEvent event = new ContainerIOUsageEvent();

            event.serviceRequests = containerMetrics.getBlkIOServiceCount();
            event.dataTransferred = containerMetrics.getBlkIOServiced();
            event.commit();
        }
    }

    private static void emitContainerCPUThrottling() {
        if (containerMetrics != null) {
            ContainerCPUThrottlingEvent event = new ContainerCPUThrottlingEvent();

Configuration enabled period
default true 30 s
profiling true 30 s

Field Type Description
serviceRequests long Block IO Request Count Number of block IO requests to the disk that have been issued by the container
dataTransferred long: bytes Block IO Transfer Number of block IO bytes that have been transferred to/from the disk by the container

ContainerConfiguration

default profiling startTime duration stackTrace 17 21 23 24

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/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.hostTotalSwapMemory = JVM.hostTotalSwapMemory();
            t.commit();

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
containerType string Container Type Container type information
cpuSlicePeriod long: microseconds CPU Slice Period Length of the scheduling period for processes within the container
cpuQuota long: microseconds CPU Quota Total available run-time allowed during each scheduling period for all tasks in the container
cpuShares long CPU Shares Relative weighting of processes with the container used for prioritizing the scheduling of processes across all containers running on a host
effectiveCpuCount long Effective CPU Count Number of effective processors that this container has available to it
memorySoftLimit long: bytes Memory Soft Limit Hint to the operating system that allows groups to specify the minimum required amount of physical memory
memoryLimit long: bytes Memory Limit Maximum amount of physical memory that can be allocated in the container
swapMemoryLimit long: bytes Memory and Swap Limit Maximum amount of physical memory and swap space, in bytes, that can be allocated in the container
hostTotalMemory long: bytes 20+ Container Host Total Memory Total memory of the host running the container
hostTotalSwapMemory long: bytes 23+ Container Host Total Swap Memory Total swap memory of the host running the container

ContainerCPUThrottling

default profiling startTime duration stackTrace 17 21 23 24

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/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/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();
        }
    }

    public static void remove() {
        PeriodicEvents.removeEvent(emitExceptionStatistics);
        PeriodicEvents.removeEvent(emitDirectBufferStatistics);

Configuration enabled period
default true 30 s
profiling true 30 s

Field Type Description
cpuElapsedSlices long CPU Elapsed Slices Number of time-slice periods that have elapsed if a CPU quota has been setup for the container
cpuThrottledSlices long CPU Throttled Slices Number of time-slice periods that the CPU has been throttled or limited due to exceeding CPU quota
cpuThrottledTime long: nanos CPU Throttled Time Total time duration, in nanoseconds, that the CPU has been throttled or limited due to exceeding CPU quota

ContainerMemoryUsage

default profiling startTime duration stackTrace 17 21 23 24

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/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/JDKEvents.java:

    private static void emitContainerCPUUsage() {
        if (containerMetrics != null) {
            ContainerCPUUsageEvent event = new ContainerCPUUsageEvent();

            event.cpuTime = containerMetrics.getCpuUsage();
            event.cpuSystemTime = containerMetrics.getCpuSystemUsage();
            event.cpuUserTime = containerMetrics.getCpuUserUsage();
            event.commit();
        }
    }
    private static void emitContainerMemoryUsage() {
        if (containerMetrics != null) {
            ContainerMemoryUsageEvent event = new ContainerMemoryUsageEvent();

            event.memoryFailCount = containerMetrics.getMemoryFailCount();
            event.memoryUsage = containerMetrics.getMemoryUsage();
            event.swapMemoryUsage = containerMetrics.getMemoryAndSwapUsage();
            event.commit();
        }
    }

    private static void emitContainerIOUsage() {
        if (containerMetrics != null) {
            ContainerIOUsageEvent event = new ContainerIOUsageEvent();

Configuration enabled period
default true 30 s
profiling true 30 s

Field Type Description
memoryFailCount long Memory Fail Count Number of times that user memory requests in the container have exceeded the memory limit
memoryUsage long: bytes Memory Usage Amount of physical memory, in bytes, that is currently allocated in the current container
swapMemoryUsage long: bytes Memory and Swap Usage Amount of physical memory and swap space, in bytes, that is currently allocated in the current container

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.Deoptimization

startTime duration graal vm only

Category: Truffle Compiler

Truffle Call Target Deoptimization

Field Type Description
engineId long 24+ EngineId Truffle Engine Unique Id
id long 23+ Id Truffle Compilable Unique Id
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
engineId long 24+ EngineId Truffle Engine Unique Id
id long 23+ Id Truffle Compilable Unique Id
source string Source Compiled Source
language string Language Guest Language
rootFunction string Root Function Root Function
reason string Reason Invalidation Reason

graal.compiler.truffle.CompilationFailure

startTime duration graal vm only

Category: Truffle Compiler

Truffe Compilation Failures

Field Type Description
engineId long 24+ EngineId Truffle Engine Unique Id
id long 23+ Id Truffle Compilable Unique Id
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
truffleTier int 23+ Tier The Tier of the Truffle Compiler
stackTrace string 23+ Exception Stack Trace Exception Stack Trace

graal.compiler.truffle.Compilation

startTime duration graal vm only

Category: Truffle Compiler

Truffe Compilation

Field Type Description
engineId long 24+ EngineId Truffle Engine Unique Id
id long 23+ Id Truffle Compilable Unique Id
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
truffleTier int 23+ Tier The Tier of the Truffle Compiler

Types

Bytecode

14+

Bytecode Instruction

Field Type Description
bytecode string Instruction

Examples 3
invokevirtual
ifeq
ifeq

CalleeMethod

No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
type string Class
name string Method Name
descriptor string Method Descriptor

Examples 3
descriptor string
(I)Ljava/lang/AbstractStringBuilder;
name string
append
type string
java/lang/AbstractStringBuilder
descriptor string
()Lorg/apache/spark/util/LongAccumulator;
name string
_executorCpuTime
type string
org/apache/spark/executor/TaskMetrics
descriptor string
(B)V
name string
putUncheckedByte
type string
jdk/jfr/internal/event/EventWriter

ChunkHeader

14+

Chunk Header No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
payload array byte Payload

Class

Java Class

Field Type Description
classLoader ClassLoader Class Loader Consider contributing a description to jfreventcollector.
name Symbol Name Consider contributing a description to jfreventcollector.
package Package Package Consider contributing a description to jfreventcollector.
modifiers int Access Modifiers
hidden boolean 15+ Hidden

ClassLoader

Java Class Loader

Field Type Description
type Class Type Consider contributing a description to jfreventcollector.
name Symbol Name Consider contributing a description to jfreventcollector.

CodeBlobType

Code Blob Type No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
type string Type

Examples 3
CodeHeap 'profiled nmethods'
CodeHeap 'profiled nmethods'
CodeHeap 'non-nmethods'

CompilerPhaseType

Compiler Phase Type No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
phase string Phase

CompilerType

14+

Compiler Type No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
compiler string Compiler

Examples 3
c2
c1
c2

CopyFailed

No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

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 No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
action string Action

Examples 3
reinterpret
reinterpret
maybe_recompile

DeoptimizationReason

14+

Deoptimization Reason No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
reason string Reason

Examples 3
unstable_if
class_check
unstable_if

FlagValueOrigin

Flag Value Origin No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
origin string Origin

Examples 3
Default
Default
Default

FrameType

Frame type No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
description string Description

Examples 3
Interpreted
Interpreted
JIT compiled

G1EvacuationStatistics

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
gcId uint GC Identifier
allocated ulong: bytes Allocated Total memory allocated by PLABs
wasted ulong: bytes Wasted Total memory wasted within PLABs due to alignment or refill
used ulong: bytes Used Total memory occupied by objects within PLABs
undoWaste ulong: bytes Undo Wasted Total memory wasted due to allocation undo within PLABs
regionEndWaste ulong: bytes Region End Wasted Total memory wasted at the end of regions due to refill
regionsRefilled uint Region Refills Number of regions refilled
numPlabsFilled ulong 17+ PLAB Fills Number of PLABs filled
directAllocated ulong: bytes Allocated (direct) Total memory allocated using direct allocation outside of PLABs
numDirectAllocated ulong 17+ Direct allocations Number of direct allocations
failureUsed ulong: bytes Used (failure) Total memory occupied by objects in regions where evacuation failed
failureWaste ulong: bytes Wasted (failure) Total memory left unused in regions where evacuation failed

Examples 2
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
916
numDirectAllocated ulong
6115354792
numPlabsFilled ulong
0
regionEndWaste ulong: bytes
0
regionsRefilled uint
0
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0
allocated ulong: bytes
1630080
directAllocated ulong: bytes
16400
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
904
numDirectAllocated ulong
5
numPlabsFilled ulong
6652858312
regionEndWaste ulong: bytes
0
regionsRefilled uint
1
undoWaste ulong: bytes
0
used ulong: bytes
1425320
wasted ulong: bytes
6456

G1HeapRegionType

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

G1 Heap Region Type No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
type string Type

Examples 2
Old
Free

G1YCType

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

G1 YC Type No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
type string Type

Examples 1
Concurrent Start

GCCause

GC Cause No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
cause string Cause

Examples 3
Allocation Failure
Allocation Failure
G1 Evacuation Pause

GCName

GC Name No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
name string Name

Examples 3
G1New
G1Old
ParallelScavenge

GCThresholdUpdater

GC Threshold Updater No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
updater string Updater

Examples 3
compute_new_size
compute_new_size
compute_new_size

GCWhen

GC When No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
when string When

Examples 3
Before GC
After GC
After GC

InflateCause

Inflation Cause No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
cause string Cause

MetadataType

Metadata Type No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
type string Type

Examples 3
Metadata
Metadata
Class

MetaspaceObjectType

Appearing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Missing in: G1GC

Metaspace Object Type No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
type string Type

Examples 3
ConstantPool
ConstMethod
Method

MetaspaceSizes

No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

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
640483328
reserved ulong: bytes
1677721600
used ulong: bytes
637281120
committed ulong: bytes
87490560
reserved ulong: bytes
1073741824
used ulong: bytes
86004336
committed ulong: bytes
552992768
reserved ulong: bytes
603979776
used ulong: bytes
551276784

Method

Java Method

Field Type Description
type Class Type Consider contributing a description to jfreventcollector.
name Symbol Name Consider contributing a description to jfreventcollector.
descriptor Symbol Descriptor Consider contributing a description to jfreventcollector.
modifiers int Access Modifiers
hidden boolean Hidden

Module

Module No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
name Symbol Name Consider contributing a description to jfreventcollector.
version Symbol Version Consider contributing a description to jfreventcollector.
location Symbol Location Consider contributing a description to jfreventcollector.
classLoader ClassLoader Class Loader Consider contributing a description to jfreventcollector.

NMTType

21+

Native Memory Tracking Type

Field Type Description
name string Name

NarrowOopMode

Narrow Oop Mode No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
mode string Mode

Examples 3
Zero based
Zero based
Zero based

NetworkInterfaceName

Network Interface No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
networkInterface string Network Interface Network Interface Name

Examples 3
en0
lo0
lo0

ObjectSpace

Appearing in: ParallelGC

Missing in: G1GC, SerialGC, ShenandoahGC, ZGC

No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

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
34359738368
size ulong: bytes
202375168
start ulong: address
34157363200
used ulong: bytes
144064608
end ulong: address
33871101952
size ulong: bytes
942669824
start ulong: address
32928432128
used ulong: bytes
0
end ulong: address
30407131136
size ulong: bytes
342360064
start ulong: address
30064771072
used ulong: bytes
274960072

OldObject

Old Object No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

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
31582952064
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
[B
package Package
null
address ulong: address
30279696552
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
30180937480
description string
null
referrer Reference
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
48
name string
java/util/concurrent/SynchronousQueue$TransferStack$SNode
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1
name string
java/util/concurrent

OldObjectArray

Old Object Array No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
size int Array Size Size of array
index int Index Index in the array

OldObjectField

Old Object Field No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
name string Field Name of field
modifiers short Field Modifiers Field modifiers

OldObjectGcRoot

GC Root No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

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 No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
system string System

OldObjectRootType

GC Root Type No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
type string Type

Package

Package No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
name Symbol Name Consider contributing a description to jfreventcollector.
module Module Module Consider contributing a description to jfreventcollector.
exported boolean Exported

Reference

Reference No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

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 No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
type string Type

Examples 3
Soft reference
Final reference
Soft reference

ShenandoahHeapRegionState

Appearing in: ShenandoahGC

Missing in: G1GC, ParallelGC, SerialGC, ZGC

Shenandoah Heap Region State No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
state string State

Examples 2
Regular
Collection Set

StackFrame

No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
method Method Java Method
lineNumber int Line Number
bytecodeIndex int Bytecode Index
type FrameType Frame Type

Examples 3
bytecodeIndex int
15
lineNumber int
3540
method Method
descriptor string
([BI)[B
hidden boolean
false
modifiers int
9
name string
copyOf
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/util/Arrays
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/util
type FrameType
JIT compiled
bytecodeIndex int
50
lineNumber int
104
method Method
descriptor string
(Ljava/io/OutputStream;ILnet/jpountz/lz4/LZ4Compressor;Ljava/util/zip/Checksum;Z)V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/net
hidden boolean
false
modifiers int
1
name string
net/jpountz/lz4/LZ4BlockOutputStream
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
22
name string
java/net
location string
null
name string
null
version string
null
name string
net/jpountz/lz4
type FrameType
JIT compiled
bytecodeIndex int
34
lineNumber int
89
method Method
descriptor string
(Ljava/lang/String;Ljava/lang/String;)V
hidden boolean
false
modifiers int
1
name string
put
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
22
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/logging/log4j/spi/DefaultThreadContextMap
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
22
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/logging/log4j/spi
type FrameType
Interpreted

StackTrace

Stacktrace No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
truncated boolean Truncated
frames array StackFrame struct Stack Frames

Symbol

Symbol No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
string string String

Examples 3
file://[...]/code/experiments/jfreventcollector/harness-124622-12434569844652140370/twitter-finagle/lib/netty-buffer-4.1.72.Final.jar
file://[...]/code/experiments/jfreventcollector/harness-141003-16632656921422798882/apache-spark/lib/netty-buffer-4.1.99.Final.jar
file://[...]/code/experiments/jfreventcollector/harness-124447-3147988932466435938/twitter-finagle/lib/netty-buffer-4.1.72.Final.jar

Thread

Thread No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

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 No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
parent ThreadGroup Parent Consider contributing a description to jfreventcollector.
name string Name

Examples 3
name string
system
parent ThreadGroup
null
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
null

ThreadState

Java Thread State

Field Type Description
name string Name

Examples 3
STATE_RUNNABLE
STATE_RUNNABLE
STATE_RUNNABLE

VMOperationType

VM Operation Type No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
type string Type

Examples 3
ClassLoaderStatsOperation
ICBufferFull
HandshakeAllThreads

VirtualSpace

No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

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
31086084096
committedSize ulong: bytes
1021313024
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4294967296
start ulong: address
30064771072
committedEnd ulong: address
30968643584
committedSize ulong: bytes
903872512
reservedEnd ulong: address
34359738368
reservedSize ulong: bytes
4294967296
start ulong: address
30064771072
committedEnd ulong: address
30407131136
committedSize ulong: bytes
342360064
reservedEnd ulong: address
32928432128
reservedSize ulong: bytes
2863661056
start ulong: address
30064771072

ZPageTypeType

15+

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Z Page Type No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
type string Type

Examples 2
Large
Small

ZStatisticsCounterType

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Z Statistics Counter No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
counter string Counter

Examples 1
Page Cache Hit L3

ZStatisticsSamplerType

Appearing in: ZGC

Missing in: G1GC, ParallelGC, SerialGC, ShenandoahGC

Z Statistics Sampler No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Field Type Description
sampler string Sampler

Examples 1
Concurrent Weak Roots OopStorageSet

XML Content Types

address

Annotation: jdk.jfr.MemoryAddress

Examples 3
10182955008
30394023936
0

bits-per-second

Annotation: jdk.jfr.DataAmount(BITS), jdk.jfr.Frequency

Examples 3
3845016
22240608
7504

bytes

Annotation: jdk.jfr.DataAmount(BYTES)

Examples 3
221952
2176
262144000

bytes-per-second

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Annotation: jdk.jfr.DataAmount(BYTES), jdk.jfr.Frequency

Examples 2
0.0
1.3699919867794466E8

certificateId

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Annotation: jdk.jfr.events.CertificateId

Examples 1
3045411335

epochmillis

Annotation: jdk.jfr.Timestamp(MILLISECONDS_SINCE_EPOCH)

Examples 3
-9223372036854775808
1727266202802
1727266203142

hertz

Annotation: jdk.jfr.Frequency

Examples 3
1000000000
10
1000000000

microseconds

17+

Annotation: jdk.jfr.Timespan(MICROSECONDS)

millis

Annotation: jdk.jfr.Timespan(MILLISECONDS)

Examples 3
9223372036854775807
792248652833
791550348833

nanos

Annotation: jdk.jfr.Timespan(NANOSECONDS)

Examples 3
-9223372036854775808
0
0

percentage

Annotation: jdk.jfr.Percentage

Examples 3
0.0010318022
0.005607464
0.98376626

tickspan

Annotation: jdk.jfr.Timespan(TICKS)

Examples 3
85214708
3350416
50271951542

tickstamp

Annotation: jdk.jfr.Timestamp(TICKS)

XML Types

Class

No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Parameter Type const Klass*
Field Type const Klass*
Java Type java.lang.Class
Examples 3
null
null
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1041
name string
[F
package Package
null

ClassLoader

No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

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

No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Parameter Type const Method*
Field Type const Method*
Examples 3
descriptor string
(Ljava/lang/String;Ljava/lang/String;)V
hidden boolean
false
modifiers int
1
name string
put
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
22
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/logging/log4j/spi/DefaultThreadContextMap
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
22
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/logging/log4j/spi
descriptor string
(Ljava/io/OutputStream;ILnet/jpountz/lz4/LZ4Compressor;Ljava/util/zip/Checksum;Z)V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/net
hidden boolean
false
modifiers int
1
name string
net/jpountz/lz4/LZ4BlockOutputStream
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
22
name string
java/net
location string
null
name string
null
version string
null
name string
net/jpountz/lz4
descriptor string
([BI)[B
hidden boolean
false
modifiers int
9
name string
copyOf
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/util/Arrays
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/util

Module

No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Parameter Type const ModuleEntry*
Field Type const ModuleEntry*
Examples 3
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/net
location string
null
name string
null
version string
null
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
21.0.1

Package

No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

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
21.0.1
name string
java/text
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/net
null

StackTrace

15+

No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Parameter Type u8
Field Type u8
Java Type jdk.types.StackTrace
Examples 3
frames StackFrame
bytecodeIndex int
50
lineNumber int
104
method Method
descriptor string
(Ljava/io/OutputStream;ILnet/jpountz/lz4/LZ4Compressor;Ljava/util/zip/Checksum;Z)V
hidden boolean
false
modifiers int
1
name string
<init>
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/net
hidden boolean
false
modifiers int
1
name string
net/jpountz/lz4/LZ4BlockOutputStream
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
22
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
frames StackFrame
bytecodeIndex int
15
lineNumber int
3540
method Method
descriptor string
([BI)[B
hidden boolean
false
modifiers int
9
name string
copyOf
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
17
name string
java/util/Arrays
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
22
name string
java/util
type FrameType
JIT compiled
truncated boolean
false
frames StackFrame
bytecodeIndex int
34
lineNumber int
89
method Method
descriptor string
(Ljava/lang/String;Ljava/lang/String;)V
hidden boolean
false
modifiers int
1
name string
put
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
22
name string
java/net
hidden boolean
false
modifiers int
1
name string
org/apache/logging/log4j/spi/DefaultThreadContextMap
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
22
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/logging/log4j/spi
type FrameType
Interpreted
truncated boolean
false

Thread

No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

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
JFR Periodic Tasks
javaThreadId long
20
osName string
JFR Periodic Tasks
osThreadId long
33027
virtual boolean
false
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
map-output-dispatcher-6
javaThreadId long
1611
osName string
map-output-dispatcher-6
osThreadId long
64299
virtual boolean
false
group ThreadGroup
name string
main
parent ThreadGroup
name string
system
parent ThreadGroup
null
javaName string
block-manager-ask-thread-pool-35
javaThreadId long
1753
osName string
block-manager-ask-thread-pool-35
osThreadId long
51991
virtual boolean
false

Ticks

unsigned

No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

Parameter Type const Ticks&
Field Type Ticks
Java Type long
Content Type tickstamp
Examples 3
388237030375
890593730875
93744217333

Tickspan

unsigned

No description available. Write your own and contribute it to jfreventcollector. or directly to the OpenJDK.

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
true
false

byte

Parameter Type s1
Field Type s1
Java Type byte

char

Parameter Type char
Field Type char
Java Type char

double

Parameter Type double
Field Type double
Java Type double
Examples 3
0.0
2.0
1.0

float

Parameter Type float
Field Type float
Java Type float
Examples 3
7.799066
7.767639
2.7926807

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
1967
98053
3

short

Parameter Type s2
Field Type s2
Java Type short

string

Parameter Type const char*
Field Type const char*
Java Type java.lang.String
Examples 3
bootstrap
[F
null

ubyte

unsigned

Parameter Type u1
Field Type u1
Java Type byte
Examples 3
7
15
32

uint

unsigned

Parameter Type unsigned
Field Type unsigned
Java Type int
Examples 3
157
8
8

ulong

unsigned

Parameter Type u8
Field Type u8
Java Type long
Examples 3
1951
65536
1908

ushort

unsigned

Parameter Type u2
Field Type u2
Java Type short
Examples 3
4
4
4