JFR Explorer

Very early preview version! Idea for this tool by Johannes Bechberger. JFRExplorer on GitHub

NameCategoryLabelAttributesFields
ThreadStartJava ApplicationJava Thread Start
NameValue
threadtrue
startTimefalse
stackTracetrue
NameTypeLabel
threadThreadNew Java Thread
parentThreadThreadParent Java Thread
ThreadEndJava ApplicationJava Thread End
NameValue
threadtrue
startTimefalse
NameTypeLabel
threadThreadJava Thread
ThreadSleepJava ApplicationJava Thread Sleep
NameValue
threadtrue
stackTracetrue
NameTypeContentTypeLabel
timelongmillisSleep Time
ThreadParkJava ApplicationJava Thread Park
NameValue
threadtrue
stackTracetrue
NameTypeContentTypeLabel
parkedClassClassClass Parked On
timeoutlongnanosPark Timeout
untillongepochmillisPark Until
addressulongaddressAddress of Object Parked
JavaMonitorEnterJava ApplicationJava Monitor Blocked
NameValue
threadtrue
stackTracetrue
NameTypeContentTypeLabel
monitorClassClassMonitor Class
previousOwnerThreadPrevious Monitor Owner
addressulongaddressMonitor Address
JavaMonitorWaitJava ApplicationJava Monitor Wait
NameValue
descriptionWaiting on a Java monitor
threadtrue
stackTracetrue
NameTypeContentTypeLabelDescription
monitorClassClassMonitor ClassClass of object waited on
notifierThreadNotifier ThreadNotifying Thread
timeoutlongmillisTimeoutMaximum wait time
timedOutbooleanTimed OutWait has been timed out
addressulongaddressMonitor AddressAddress of object waited on
JavaMonitorInflateJava ApplicationJava Monitor Inflated
NameValue
threadtrue
stackTracetrue
NameTypeContentTypeLabelDescription
monitorClassClassMonitor Class
addressulongaddressMonitor Address
causeInflateCauseMonitor Inflation CauseCause of inflation
SyncOnValueBasedClassJVM -> DiagnosticsValue Based Class Synchronization
NameValue
threadtrue
stackTracetrue
startTimefalse
experimentaltrue
NameTypeLabel
valueBasedClassClassValue Based Class
BiasedLockRevocationJVM -> RuntimeBiased Lock Revocation
NameValue
descriptionRevoked bias of object
threadtrue
stackTracetrue
NameTypeLabelDescription
lockClassClassLock ClassClass of object whose biased lock was revoked
safepointIdulongSafepoint Identifier
previousOwnerThreadPrevious OwnerThread owning the bias before revocation
BiasedLockSelfRevocationJVM -> RuntimeBiased Lock Self Revocation
NameValue
descriptionRevoked bias of object biased towards own thread
threadtrue
stackTracetrue
NameTypeLabelDescription
lockClassClassLock ClassClass of object whose biased lock was revoked
BiasedLockClassRevocationJVM -> RuntimeBiased Lock Class Revocation
NameValue
descriptionRevoked biases for all instances of a class
threadtrue
stackTracetrue
NameTypeLabelDescription
revokedClassClassRevoked ClassClass whose biased locks were revoked
disableBiasingbooleanDisable Further BiasingWhether further biasing for instances of this class will be allowed
safepointIdulongSafepoint Identifier
ReservedStackActivationJVM -> RuntimeReserved Stack Activation
NameValue
descriptionActivation of Reserved Stack Area caused by stack overflow with ReservedStackAccess annotated method in call stack
threadtrue
stackTracetrue
startTimefalse
NameTypeLabel
methodMethodJava Method
ClassLoadJVM -> Class LoadingClass Load
NameValue
threadtrue
stackTracetrue
NameTypeLabel
loadedClassClassLoaded Class
definingClassLoaderClassLoaderDefining Class Loader
initiatingClassLoaderClassLoaderInitiating Class Loader
ClassDefineJVM -> Class LoadingClass Define
NameValue
threadtrue
stackTracetrue
startTimefalse
NameTypeLabel
definedClassClassDefined Class
definingClassLoaderClassLoaderDefining Class Loader
ClassRedefinitionJVM -> Class LoadingClass Redefinition
NameValue
threadfalse
stackTracefalse
startTimefalse
NameTypeLabelDescription
redefinedClassClassRedefined Class
classModificationCountintClass Modification CountThe number of times the class has changed
redefinitionIdulongClass Redefinition Id
RedefineClassesJVM -> Class LoadingRedefine Classes
NameValue
threadtrue
stackTracetrue
NameTypeLabel
classCountintClass Count
redefinitionIdulongClass Redefinition Id
RetransformClassesJVM -> Class LoadingRetransform Classes
NameValue
threadtrue
stackTracetrue
NameTypeLabel
classCountintClass Count
redefinitionIdulongClass Redefinition Id
ClassUnloadJVM -> Class LoadingClass Unload
NameValue
threadtrue
startTimefalse
NameTypeLabel
unloadedClassClassUnloaded Class
definingClassLoaderClassLoaderDefining Class Loader
IntFlagChangedJVM -> FlagInt Flag Changed
NameValue
startTimefalse
NameTypeLabel
namestringName
oldValueintOld Value
newValueintNew Value
originFlagValueOriginOrigin
UnsignedIntFlagChangedJVM -> FlagUnsigned Int Flag Changed
NameValue
startTimefalse
NameTypeLabel
namestringName
oldValueuintOld Value
newValueuintNew Value
originFlagValueOriginOrigin
LongFlagChangedJVM -> FlagLong Flag Changed
NameValue
startTimefalse
NameTypeLabel
namestringName
oldValuelongOld Value
newValuelongNew Value
originFlagValueOriginOrigin
UnsignedLongFlagChangedJVM -> FlagUnsigned Long Flag Changed
NameValue
startTimefalse
NameTypeLabel
namestringName
oldValueulongOld Value
newValueulongNew Value
originFlagValueOriginOrigin
DoubleFlagChangedJVM -> FlagDouble Flag Changed
NameValue
startTimefalse
NameTypeLabel
namestringName
oldValuedoubleOld Value
newValuedoubleNew Value
originFlagValueOriginOrigin
BooleanFlagChangedJVM -> FlagBoolean Flag Changed
NameValue
startTimefalse
NameTypeLabel
namestringName
oldValuebooleanOld Value
newValuebooleanNew Value
originFlagValueOriginOrigin
StringFlagChangedJVM -> FlagString Flag Changed
NameValue
startTimefalse
NameTypeLabel
namestringName
oldValuestringOld Value
newValuestringNew Value
originFlagValueOriginOrigin
GCHeapSummaryJVM -> GC -> HeapHeap Summary
NameValue
startTimefalse
NameTypeContentTypeLabelDescription
gcIduintGC Identifier
whenGCWhenWhen
heapSpaceVirtualSpaceHeap Space
heapUsedulongbytesHeap UsedBytes allocated by objects in the heap
MetaspaceSummaryJVM -> GC -> HeapMetaspace Summary
NameValue
startTimefalse
NameTypeContentTypeLabel
gcIduintGC Identifier
whenGCWhenWhen
gcThresholdulongbytesGC Threshold
metaspaceMetaspaceSizesTotal
dataSpaceMetaspaceSizesData
classSpaceMetaspaceSizesClass
MetaspaceGCThresholdJVM -> GC -> MetaspaceMetaspace GC Threshold
NameValue
startTimefalse
NameTypeContentTypeLabel
oldValueulongbytesOld Value
newValueulongbytesNew Value
updaterGCThresholdUpdaterUpdater
MetaspaceAllocationFailureJVM -> GC -> MetaspaceMetaspace Allocation Failure
NameValue
startTimefalse
stackTracetrue
NameTypeContentTypeLabel
classLoaderClassLoaderClass Loader
hiddenClassLoaderbooleanHidden Class Loader
sizeulongbytesSize
metadataTypeMetadataTypeMetadata Type
metaspaceObjectTypeMetaspaceObjectTypeMetaspace Object Type
MetaspaceOOMJVM -> GC -> MetaspaceMetaspace Out of Memory
NameValue
startTimefalse
stackTracetrue
NameTypeContentTypeLabel
classLoaderClassLoaderClass Loader
hiddenClassLoaderbooleanHidden Class Loader
sizeulongbytesSize
metadataTypeMetadataTypeMetadata Type
metaspaceObjectTypeMetaspaceObjectTypeMetaspace Object Type
MetaspaceChunkFreeListSummaryJVM -> GC -> MetaspaceMetaspace Chunk Free List Summary
NameValue
startTimefalse
NameTypeContentTypeLabel
gcIduintGC Identifier
whenGCWhenWhen
metadataTypeMetadataTypeMetadata Type
specializedChunksulongSpecialized Chunks
specializedChunksTotalSizeulongbytesSpecialized Chunks Total Size
smallChunksulongSmall Chunks
smallChunksTotalSizeulongbytesSmall Chunks Total Size
mediumChunksulongMedium Chunks
mediumChunksTotalSizeulongbytesMedium Chunks Total Size
humongousChunksulongHumongous Chunks
humongousChunksTotalSizeulongbytesHumongous Chunks Total Size
PSHeapSummaryJVM -> GC -> HeapParallel Scavenge Heap Summary
NameValue
startTimefalse
NameTypeLabel
gcIduintGC Identifier
whenGCWhenWhen
oldSpaceVirtualSpaceOld Space
oldObjectSpaceObjectSpaceOld Object Space
youngSpaceVirtualSpaceYoung Space
edenSpaceObjectSpaceEden Space
fromSpaceObjectSpaceFrom Space
toSpaceObjectSpaceTo Space
G1HeapSummaryJVM -> GC -> HeapG1 Heap Summary
NameValue
startTimefalse
NameTypeContentTypeLabel
gcIduintGC Identifier
whenGCWhenWhen
edenUsedSizeulongbytesEden Used Size
edenTotalSizeulongbytesEden Total Size
survivorUsedSizeulongbytesSurvivor Used Size
numberOfRegionsuintNumber of Regions
GarbageCollectionJVM -> GC -> CollectorGarbage Collection
NameValue
descriptionGarbage collection performed by the JVM
NameTypeLabelDescription
gcIduintGC Identifier
nameGCNameNameThe name of the Garbage Collector
causeGCCauseCauseThe reason for triggering this Garbage Collection
sumOfPausesTickspanSum of PausesSum of all the times in which Java execution was paused during the garbage collection
longestPauseTickspanLongest PauseLongest individual pause during the garbage collection
SystemGCJVM -> GC -> CollectorSystem GC
NameValue
stackTracetrue
startTimetrue
threadtrue
NameTypeLabel
invokedConcurrentbooleanInvoked Concurrent
ParallelOldGarbageCollectionJVM -> GC -> CollectorParallel Old Garbage Collection
NameValue
descriptionExtra information specific to Parallel Old Garbage Collections
NameTypeContentTypeLabelDescription
gcIduintGC Identifier
densePrefixulongaddressDense PrefixThe address of the dense prefix, used when compacting
YoungGarbageCollectionJVM -> GC -> CollectorYoung Garbage Collection
NameValue
descriptionExtra information specific to Young Garbage Collections
NameTypeLabel
gcIduintGC Identifier
tenuringThresholduintTenuring Threshold
OldGarbageCollectionJVM -> GC -> CollectorOld Garbage Collection
NameValue
descriptionExtra information specific to Old Garbage Collections
NameTypeLabel
gcIduintGC Identifier
G1GarbageCollectionJVM -> GC -> CollectorG1 Young Garbage Collection
NameValue
descriptionExtra information specific to G1 Young Garbage Collections
NameTypeLabel
gcIduintGC Identifier
typeG1YCTypeType
G1MMUJVM -> GC -> DetailedG1 MMU Information
NameValue
startTimefalse
NameTypeContentTypeLabelDescription
gcIduintGC Identifier
timeSlicelongmillisTime SliceTime slice used to calculate MMU
gcTimelongmillisGC TimeTime stopped because of GC during last time slice
pauseTargetlongmillisPause TargetMax time allowed to be spent on GC during last time slice
EvacuationInformationJVM -> GC -> DetailedEvacuation Information
NameValue
startTimefalse
NameTypeContentTypeLabelDescription
gcIduintGC Identifier
cSetRegionsuintCollection Set Regions
cSetUsedBeforeulongbytesCollection Set BeforeMemory usage before GC in the collection set regions
cSetUsedAfterulongbytesCollection Set AfterMemory usage after GC in the collection set regions
allocationRegionsuintAllocation RegionsRegions chosen as allocation regions during evacuation (includes survivors and old space regions)
allocationRegionsUsedBeforeulongbytesAllocation Regions BeforeMemory usage before GC in allocation regions
allocationRegionsUsedAfterulongbytesAllocation Regions AfterMemory usage after GC in allocation regions
bytesCopiedulongbytesBytes Copied
regionsFreeduintRegions Freed
GCReferenceStatisticsJVM -> GC -> ReferenceGC Reference Statistics
NameValue
startTimefalse
descriptionTotal count of processed references during GC
NameTypeLabel
gcIduintGC Identifier
typeReferenceTypeType
countulongTotal Count
ObjectCountAfterGCJVM -> GC -> DetailedObject Count after GC
NameValue
startTimefalse
NameTypeContentTypeLabel
gcIduintGC Identifier
objectClassClassObject Class
countlongCount
totalSizeulongbytesTotal Size
G1EvacuationYoungStatisticsJVM -> GC -> DetailedG1 Evacuation Statistics for Young
NameValue
startTimefalse
descriptionMemory related evacuation statistics during GC for the young generation
NameTypeLabel
statisticsG1EvacuationStatisticsEvacuation Statistics
G1EvacuationOldStatisticsJVM -> GC -> DetailedG1 Evacuation Memory Statistics for Old
NameValue
startTimefalse
descriptionMemory related evacuation statistics during GC for the old generation
NameTypeLabel
statisticsG1EvacuationStatisticsEvacuation Statistics
G1BasicIHOPJVM -> GC -> DetailedG1 Basic IHOP Statistics
NameValue
startTimefalse
descriptionBasic statistics related to current IHOP calculation
NameTypeContentTypeLabelDescription
gcIduintGC Identifier
thresholdulongbytesCurrent IHOP ThresholdCurrent IHOP threshold
thresholdPercentagefloatpercentageCurrent IHOP ThresholdCurrent IHOP threshold in percent of old generation
targetOccupancyulongbytesTarget OccupancyTarget old generation occupancy to reach at the start of mixed GC
currentOccupancyulongbytesCurrent OccupancyCurrent old generation occupancy
recentMutatorAllocationSizeulongbytesRecent Mutator Allocation SizeMutator allocation during mutator operation in the most recent interval
recentMutatorDurationlongmillisRecent Mutator DurationTime the mutator ran in the most recent interval
recentAllocationRatedoublebytes-per-secondRecent Allocation RateAllocation rate of the mutator in the most recent interval in bytes/second
lastMarkingDurationlongmillisLast Marking DurationLast time from the end of the last concurrent start to the first mixed GC
G1AdaptiveIHOPJVM -> GC -> DetailedG1 Adaptive IHOP Statistics
NameValue
startTimefalse
descriptionStatistics related to current adaptive IHOP calculation
NameTypeContentTypeLabelDescription
gcIduintGC Identifier
thresholdulongbytesThresholdCurrent IHOP Threshold
thresholdPercentagefloatpercentageThresholdCurrent IHOP threshold in percent of the internal target occupancy
ihopTargetOccupancyulongbytesIHOP Target OccupancyInternal target old generation occupancy to reach at the start of mixed GC
currentOccupancyulongbytesCurrent OccupancyCurrent old generation occupancy
additionalBufferSizeulongbytesAdditional BufferAdditional buffer size
predictedAllocationRatedoublebytes-per-secondPredicted Allocation RateCurrent predicted allocation rate for the mutator in bytes/second
predictedMarkingDurationlongmillisPredicted Marking DurationCurrent predicted time from the end of the last concurrent start to the first mixed GC
predictionActivebooleanPrediction ActiveIndicates whether the adaptive IHOP prediction is active
PromoteObjectInNewPLABJVM -> GC -> DetailedPromotion in new PLAB
NameValue
descriptionObject survived scavenge and was copied to a new Promotion Local Allocation Buffer (PLAB). Supported GCs are Parallel Scavange, G1 and CMS with Parallel New. Due to promotion being done in parallel an object might be reported multiple times as the GC threads race to copy all objects.
threadtrue
stackTracefalse
startTimefalse
NameTypeContentTypeLabelDescription
gcIduintGC IdentifierIdentifier signifying GC during which the object was promoted
objectClassClassObject ClassClass of promoted object
objectSizeulongbytesObject SizeSize of promoted object
tenuringAgeuintObject Tenuring AgeTenuring age of a surviving object before being copied. The tenuring age of an object is a value between 0-15 and is incremented each scavange the object survives. Newly allocated objects have tenuring age 0.
tenuredbooleanTenuredTrue if object was promoted to Old space, otherwise the object was aged and copied to a Survivor space
plabSizeulongbytesPLAB SizeSize of the allocated PLAB to which the object was copied
PromoteObjectOutsidePLABJVM -> GC -> DetailedPromotion outside PLAB
NameValue
descriptionObject survived scavenge and was copied directly to the heap. Supported GCs are Parallel Scavange, G1 and CMS with Parallel New. Due to promotion being done in parallel an object might be reported multiple times as the GC threads race to copy all objects.
threadtrue
stackTracefalse
startTimefalse
NameTypeContentTypeLabelDescription
gcIduintGC IdentifierIdentifier signifying GC during which the object was promoted
objectClassClassObject ClassClass of promoted object
objectSizeulongbytesObject SizeSize of promoted object
tenuringAgeuintObject Tenuring AgeTenuring age of a surviving object before being copied. The tenuring age of an object is a value between 0-15 and is incremented each scavange the object survives. Newly allocated objects have tenuring age 0.
tenuredbooleanTenuredTrue if object was promoted to Old space, otherwise the object was aged and copied to a Survivor space
PromotionFailedJVM -> GC -> DetailedPromotion Failed
NameValue
startTimefalse
descriptionPromotion of an object failed
NameTypeLabel
gcIduintGC Identifier
promotionFailedCopyFailedPromotion Failed Data
threadThreadRunning thread
EvacuationFailedJVM -> GC -> DetailedEvacuation Failed
NameValue
startTimefalse
descriptionEvacuation of an object failed
NameTypeLabel
gcIduintGC Identifier
evacuationFailedCopyFailedEvacuation Failed Data
ConcurrentModeFailureJVM -> GC -> DetailedConcurrent Mode Failure
NameValue
startTimefalse
descriptionConcurrent Mode failed
NameTypeLabel
gcIduintGC Identifier
GCPhasePauseJVM -> GC -> PhasesGC Phase Pause
NameValue
threadtrue
NameTypeLabel
gcIduintGC Identifier
namestringName
GCPhasePauseLevel1JVM -> GC -> PhasesGC Phase Pause Level 1
NameValue
threadtrue
NameTypeLabel
gcIduintGC Identifier
namestringName
GCPhasePauseLevel2JVM -> GC -> PhasesGC Phase Pause Level 2
NameValue
threadtrue
NameTypeLabel
gcIduintGC Identifier
namestringName
GCPhasePauseLevel3JVM -> GC -> PhasesGC Phase Pause Level 3
NameValue
threadtrue
NameTypeLabel
gcIduintGC Identifier
namestringName
GCPhasePauseLevel4JVM -> GC -> PhasesGC Phase Pause Level 4
NameValue
threadtrue
NameTypeLabel
gcIduintGC Identifier
namestringName
GCPhaseConcurrentJVM -> GC -> PhasesGC Phase Concurrent
NameValue
threadtrue
NameTypeLabel
gcIduintGC Identifier
namestringName
GCPhaseConcurrentLevel1JVM -> GC -> PhasesGC Phase Concurrent Level 1
NameValue
threadtrue
NameTypeLabel
gcIduintGC Identifier
namestringName
GCPhaseParallelJVM -> GC -> PhasesGC Phase Parallel
NameValue
startTimetrue
threadtrue
descriptionGC phases for parallel workers
NameTypeLabel
gcIduintGC Identifier
gcWorkerIduintGC Worker Identifier
namestringName
AllocationRequiringGCJVM -> GC -> DetailedAllocation Requiring GC
NameValue
threadtrue
stackTracetrue
startTimefalse
NameTypeContentTypeLabel
gcIduintPending GC Identifier
sizeulongbytesAllocation Size
TenuringDistributionJVM -> GC -> DetailedTenuring Distribution
NameValue
startTimefalse
NameTypeContentTypeLabel
gcIduintGC Identifier
ageuintAge
sizeulongbytesSize
G1HeapRegionTypeChangeJVM -> GC -> DetailedG1 Heap Region Type Change
NameValue
descriptionInformation about a G1 heap region type change
startTimefalse
NameTypeContentTypeLabel
indexuintIndex
fromG1HeapRegionTypeFrom
toG1HeapRegionTypeTo
startulongaddressStart
usedulongbytesUsed
CompilationJVM -> CompilerCompilation
NameValue
threadtrue
commitState_thread_in_native
NameTypeContentTypeLabel
compileIduintCompilation Identifier
compilerCompilerTypeCompiler
methodMethodMethod
compileLevelushortCompilation Level
succededbooleanSucceeded
isOsrbooleanOn Stack Replacement
codeSizeulongbytesCompiled Code Size
inlinedBytesulongbytesInlined Code Size
CompilerPhaseJVM -> CompilerCompiler Phase
NameValue
threadtrue
NameTypeLabel
phaseCompilerPhaseTypeCompile Phase
compileIduintCompilation Identifier
phaseLevelushortPhase Level
CompilationFailureJVM -> CompilerCompilation Failure
NameValue
threadtrue
startTimefalse
NameTypeLabel
failureMessagestringFailure Message
compileIduintCompilation Identifier
CompilerInliningJVM -> Compiler -> OptimizationMethod Inlining
NameValue
threadtrue
startTimefalse
commitState_thread_in_native
NameTypeLabel
compileIduintCompilation Identifier
callerMethodCaller Method
calleeCalleeMethodCallee Method
succeededbooleanSucceeded
messagestringMessage
bciintBytecode Index
SweepCodeCacheJVM -> Code SweeperSweep Code Cache
NameValue
threadtrue
NameTypeLabel
sweepIdintSweep Identifier
sweptCountuintMethods Swept
flushedCountuintMethods Flushed
zombifiedCountuintMethods Zombified
CodeCacheFullJVM -> Code CacheCode Cache Full
NameValue
threadtrue
startTimefalse
NameTypeContentTypeLabel
codeBlobTypeCodeBlobTypeCode Heap
startAddressulongaddressStart Address
commitedTopAddressulongaddressCommited Top
reservedTopAddressulongaddressReserved Top
entryCountintEntries
methodCountintMethods
adaptorCountintAdaptors
unallocatedCapacityulongbytesUnallocated
fullCountintFull Count
DeoptimizationJVM -> CompilerDeoptimization
NameValue
threadtrue
stackTracetrue
startTimefalse
NameTypeLabel
compileIduintCompilation Identifier
compilerCompilerTypeCompiler
methodMethodMethod
lineNumberintLine Number
bciintBytecode Index
instructionBytecodeInstruction
reasonDeoptimizationReasonReason
actionDeoptimizationActionAction
SafepointBeginJVM -> Runtime -> SafepointSafepoint Begin
NameValue
descriptionSafepointing begin
threadtrue
NameTypeLabelDescription
safepointIdulongSafepoint Identifier
totalThreadCountintTotal ThreadsThe total number of threads at the start of safe point
jniCriticalThreadCountintJNI Critical ThreadsThe number of threads in JNI critical sections
SafepointStateSynchronizationJVM -> Runtime -> SafepointSafepoint State Synchronization
NameValue
descriptionSynchronize run state of threads
threadtrue
NameTypeLabelDescription
safepointIdulongSafepoint Identifier
initialThreadCountintInitial ThreadsThe number of threads running at the beginning of state check
runningThreadCountintRunning ThreadsThe number of threads still running
iterationsintIterationsNumber of state check iterations
SafepointCleanupJVM -> Runtime -> SafepointSafepoint Cleanup
NameValue
descriptionSafepointing begin running cleanup tasks
threadtrue
NameTypeLabel
safepointIdulongSafepoint Identifier
SafepointCleanupTaskJVM -> Runtime -> SafepointSafepoint Cleanup Task
NameValue
descriptionSafepointing begin running cleanup tasks
threadtrue
NameTypeLabelDescription
safepointIdulongSafepoint Identifier
namestringTask NameThe task name
SafepointEndJVM -> Runtime -> SafepointSafepoint End
NameValue
descriptionSafepointing end
threadtrue
NameTypeLabel
safepointIdulongSafepoint Identifier
ExecuteVMOperationJVM -> RuntimeVM Operation
NameValue
descriptionExecution of a VM Operation
threadtrue
NameTypeLabelDescription
operationVMOperationTypeOperation
safepointbooleanAt SafepointIf the operation occured at a safepoint
blockingbooleanCaller BlockedIf the calling thread was blocked until the operation was complete
callerThreadCallerThread requesting operation. If non-blocking, will be set to 0 indicating thread is unknown
safepointIdulongSafepoint IdentifierThe safepoint (if any) under which this operation was completed
ShutdownJVM -> RuntimeJVM Shutdown
NameValue
descriptionJVM shutting down
threadtrue
stackTracetrue
startTimefalse
NameTypeLabelDescription
reasonstringReasonReason for JVM shutdown
ObjectAllocationInNewTLABJava ApplicationAllocation in new TLAB
NameValue
descriptionAllocation in new Thread Local Allocation Buffer
threadtrue
stackTracetrue
startTimefalse
NameTypeContentTypeLabelDescription
objectClassClassObject ClassClass of allocated object
allocationSizeulongbytesAllocation Size
tlabSizeulongbytesTLAB Size
ObjectAllocationOutsideTLABJava ApplicationAllocation outside TLAB
NameValue
descriptionAllocation outside Thread Local Allocation Buffers
threadtrue
stackTracetrue
startTimefalse
NameTypeContentTypeLabelDescription
objectClassClassObject ClassClass of allocated object
allocationSizeulongbytesAllocation Size
ObjectAllocationSampleJava ApplicationObject Allocation Sample
NameValue
threadtrue
stackTracetrue
startTimefalse
throttletrue
NameTypeContentTypeLabelDescription
objectClassClassObject ClassClass of allocated object
weightlongbytesSample WeightThe 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
OldObjectSampleJVM -> ProfilingOld Object Sample
NameValue
descriptionA potential memory leak
stackTracetrue
threadtrue
startTimefalse
cutofftrue
NameTypeContentTypeLabelDescription
allocationTimeTicksAllocation Time
objectAgeTickspanObject Age
lastKnownHeapUsageulongbytesLast Known Heap Usage
objectOldObjectObject
arrayElementsintArray ElementsIf the object is an array, the number of elements, or -1 if it is not an array
rootOldObjectGcRootGC Root
DumpReasonFlight RecorderRecording Reason
NameValue
descriptionWho requested the recording and why
startTimefalse
NameTypeLabelDescription
reasonstringReasonReason for writing recording data to disk
recordingIdintRecording IdId of the recording that triggered the dump, or -1 if it was not related to a recording
DataLossFlight RecorderData Loss
NameValue
descriptionData could not be copied out from a buffer, typically because of contention
startTimefalse
NameTypeContentTypeLabelDescription
amountulongbytesAmountAmount lost data
totalulongbytesTotalTotal lost amount for thread
JVMInformationJVMJVM Information
NameValue
descriptionDescription of JVM and the Java application
periodendChunk
NameTypeContentTypeLabel
jvmNamestringJVM Name
jvmVersionstringJVM Version
jvmArgumentsstringJVM Command Line Arguments
jvmFlagsstringJVM Settings File Arguments
javaArgumentsstringJava Application Arguments
jvmStartTimelongepochmillisJVM Start Time
pidlongProcess Identifier
OSInformationOperating SystemOS Information
NameValue
periodendChunk
NameTypeLabel
osVersionstringOS Version
VirtualizationInformationOperating SystemVirtualization Information
NameValue
periodendChunk
NameTypeLabel
namestringName
InitialSystemPropertyJVMInitial System Property
NameValue
descriptionSystem Property at JVM start
periodendChunk
NameTypeLabel
keystringKey
valuestringValue
InitialEnvironmentVariableOperating SystemInitial Environment Variable
NameValue
periodendChunk
NameTypeLabel
keystringKey
valuestringValue
SystemProcessOperating SystemSystem Process
NameValue
periodendChunk
NameTypeLabel
pidstringProcess Identifier
commandLinestringCommand Line
CPUInformationOperating System -> ProcessorCPU Information
NameValue
periodendChunk
NameTypeLabel
cpustringType
descriptionstringDescription
socketsuintSockets
coresuintCores
hwThreadsuintHardware Threads
CPUTimeStampCounterOperating System -> ProcessorCPU Time Stamp Counter
NameValue
periodendChunk
NameTypeContentTypeLabel
fastTimeEnabledbooleanFast Time
fastTimeAutoEnabledbooleanTrusted Platform
osFrequencylonghertzOS Frequency
fastTimeFrequencylonghertzFast Time Frequency
CPULoadOperating System -> ProcessorCPU Load
NameValue
descriptionOS CPU Load
periodeveryChunk
NameTypeContentTypeLabel
jvmUserfloatpercentageJVM User
jvmSystemfloatpercentageJVM System
machineTotalfloatpercentageMachine Total
ThreadCPULoadOperating System -> ProcessorThread CPU Load
NameValue
periodeveryChunk
threadtrue
NameTypeContentTypeLabelDescription
userfloatpercentageUser Mode CPU LoadUser mode thread CPU load
systemfloatpercentageSystem Mode CPU LoadSystem mode thread CPU load
ThreadContextSwitchRateOperating System -> ProcessorThread Context Switch Rate
NameValue
periodeveryChunk
NameTypeContentTypeLabelDescription
switchRatefloathertzSwitch RateNumber of context switches per second
NetworkUtilizationOperating System -> NetworkNetwork Utilization
NameValue
periodeveryChunk
NameTypeContentTypeLabelDescription
networkInterfaceNetworkInterfaceNameNetwork InterfaceNetwork Interface Name
readRatelongbits-per-secondRead RateNumber of incoming bits per second
writeRatelongbits-per-secondWrite RateNumber of outgoing bits per second
JavaThreadStatisticsJava Application -> StatisticsJava Thread Statistics
NameValue
periodeveryChunk
NameTypeLabelDescription
activeCountlongActive ThreadsNumber of live active threads including both daemon and non-daemon threads
daemonCountlongDaemon ThreadsNumber of live daemon threads
accumulatedCountlongAccumulated ThreadsNumber of threads created and also started since JVM start
peakCountlongPeak ThreadsPeak live thread count since JVM start or when peak count was reset
ClassLoadingStatisticsJava Application -> StatisticsClass Loading Statistics
NameValue
periodeveryChunk
NameTypeLabelDescription
loadedClassCountlongLoaded Class CountNumber of classes loaded since JVM start
unloadedClassCountlongUnloaded Class CountNumber of classes unloaded since JVM start
ClassLoaderStatisticsJava Application -> StatisticsClass Loader Statistics
NameValue
periodeveryChunk
NameTypeContentTypeLabelDescription
classLoaderClassLoaderClass Loader
parentClassLoaderClassLoaderParent Class Loader
classLoaderDataulongaddressClassLoaderData PointerPointer to the ClassLoaderData structure in the JVM
classCountlongClassesNumber of loaded classes
chunkSizeulongbytesTotal Chunk SizeTotal size of all allocated metaspace chunks (each chunk has several blocks)
blockSizeulongbytesTotal Block SizeTotal size of all allocated metaspace blocks (each chunk has several blocks)
hiddenClassCountlongHidden ClassesNumber of hidden classes
hiddenChunkSizeulongbytesTotal Hidden Classes Chunk SizeTotal size of all allocated metaspace chunks for hidden classes (each chunk has several blocks)
hiddenBlockSizeulongbytesTotal Hidden Classes Block SizeTotal size of all allocated metaspace blocks for hidden classes (each chunk has several blocks)
SymbolTableStatisticsJVM -> Runtime -> TablesSymbol Table Statistics
NameValue
periodeveryChunk
NameTypeContentTypeLabelDescription
bucketCountulongBucket CountNumber of buckets
entryCountulongEntry CountNumber of all entries
totalFootprintulongbytesTotal FootprintTotal memory footprint (the table itself plus all of the entries)
bucketCountMaximumulongMaximum Bucket CountThe maximum bucket length (entries in a single bucket)
bucketCountAveragefloatAverage Bucket CountThe average bucket length
bucketCountVariancefloatBucket Count VarianceHow far bucket lengths are spread out from their average value
bucketCountStandardDeviationfloatBucket Count Standard DeviationHow far bucket lengths are spread out from their mean (expected) value
insertionRatefloatInsertion RateHow many items were added since last event (per second)
removalRatefloatRemoval RateHow many items were removed since last event (per second)
StringTableStatisticsJVM -> Runtime -> TablesString Table Statistics
NameValue
periodeveryChunk
NameTypeContentTypeLabelDescription
bucketCountulongBucket CountNumber of buckets
entryCountulongEntry CountNumber of all entries
totalFootprintulongbytesTotal FootprintTotal memory footprint (the table itself plus all of the entries)
bucketCountMaximumulongMaximum Bucket CountThe maximum bucket length (entries in a single bucket)
bucketCountAveragefloatAverage Bucket CountThe average bucket length
bucketCountVariancefloatBucket Count VarianceHow far bucket lengths are spread out from their average value
bucketCountStandardDeviationfloatBucket Count Standard DeviationHow far bucket lengths are spread out from their mean (expected) value
insertionRatefloatInsertion RateHow many items were added since last event (per second)
removalRatefloatRemoval RateHow many items were removed since last event (per second)
PlaceholderTableStatisticsJVM -> Runtime -> TablesPlaceholder Table Statistics
NameValue
periodeveryChunk
NameTypeContentTypeLabelDescription
bucketCountulongBucket CountNumber of buckets
entryCountulongEntry CountNumber of all entries
totalFootprintulongbytesTotal FootprintTotal memory footprint (the table itself plus all of the entries)
bucketCountMaximumulongMaximum Bucket CountThe maximum bucket length (entries in a single bucket)
bucketCountAveragefloatAverage Bucket CountThe average bucket length
bucketCountVariancefloatBucket Count VarianceHow far bucket lengths are spread out from their average value
bucketCountStandardDeviationfloatBucket Count Standard DeviationHow far bucket lengths are spread out from their mean (expected) value
insertionRatefloatInsertion RateHow many items were added since last event (per second)
removalRatefloatRemoval RateHow many items were removed since last event (per second)
LoaderConstraintsTableStatisticsJVM -> Runtime -> TablesLoader Constraints Table Statistics
NameValue
periodeveryChunk
NameTypeContentTypeLabelDescription
bucketCountulongBucket Count
entryCountulongEntry CountNumber of all entries
totalFootprintulongbytesTotal FootprintTotal memory footprint (the table itself plus all of the entries)
bucketCountMaximumulongMaximum Bucket CountThe maximum bucket length (entries in a single bucket)
bucketCountAveragefloatAverage Bucket CountThe average bucket length
bucketCountVariancefloatBucket Count VarianceHow far bucket lengths are spread out from their average value
bucketCountStandardDeviationfloatBucket Count Standard DeviationHow far bucket lengths are spread out from their mean (expected) value
insertionRatefloatInsertion RateHow many items were added since last event (per second)
removalRatefloatRemoval RateHow many items were removed since last event (per second)
ProtectionDomainCacheTableStatisticsJVM -> Runtime -> TablesProtection Domain Cache Table Statistics
NameValue
periodeveryChunk
NameTypeContentTypeLabelDescription
bucketCountulongBucket CountNumber of buckets
entryCountulongEntry CountNumber of all entries
totalFootprintulongbytesTotal FootprintTotal memory footprint (the table itself plus all of the entries)
bucketCountMaximumulongMaximum Bucket CountThe maximum bucket length (entries in a single bucket)
bucketCountAveragefloatAverage Bucket CountThe average bucket length
bucketCountVariancefloatBucket Count VarianceHow far bucket lengths are spread out from their average value
bucketCountStandardDeviationfloatBucket Count Standard DeviationHow far bucket lengths are spread out from their mean (expected) value
insertionRatefloatInsertion RateHow many items were added since last event (per second)
removalRatefloatRemoval RateHow many items were removed since last event (per second)
ThreadAllocationStatisticsJava Application -> StatisticsThread Allocation Statistics
NameValue
periodeveryChunk
NameTypeContentTypeLabelDescription
allocatedulongbytesAllocatedApproximate number of bytes allocated since thread start
threadThreadThread
PhysicalMemoryOperating System -> MemoryPhysical Memory
NameValue
descriptionOS Physical Memory
periodeveryChunk
NameTypeContentTypeLabelDescription
totalSizeulongbytesTotal SizeTotal amount of physical memory available to OS
usedSizeulongbytesUsed SizeTotal amount of physical memory in use
ExecutionSampleJVM -> ProfilingMethod Profiling Sample
NameValue
descriptionSnapshot of a threads state
periodeveryChunk
NameTypeLabel
sampledThreadThreadThread
stackTraceStackTraceStack Trace
stateThreadStateThread State
NativeMethodSampleJVM -> ProfilingMethod Profiling Sample Native
NameValue
descriptionSnapshot of a threads state when in native
periodeveryChunk
NameTypeLabel
sampledThreadThreadThread
stackTraceStackTraceStack Trace
stateThreadStateThread State
ThreadDumpJVM -> RuntimeThread Dump
NameValue
periodeveryChunk
NameTypeLabel
resultstringThread Dump
NativeLibraryJVM -> RuntimeNative Library
NameValue
periodeveryChunk
NameTypeContentTypeLabelDescription
namestringName
baseAddressulongaddressBase AddressStarting address of the module
topAddressulongaddressTop AddressEnding address of the module
ModuleRequireJVM -> Runtime -> ModulesModule Require
NameValue
threadfalse
periodeveryChunk
descriptionA directed edge representing a dependency
NameTypeLabel
sourceModuleSource Module
requiredModuleModuleRequired Module
ModuleExportJVM -> Runtime -> ModulesModule Export
NameValue
threadfalse
periodeveryChunk
NameTypeLabelDescription
exportedPackagePackageExported Package
targetModuleModuleTarget ModuleModule to which the package is qualifiedly exported. If null or N/A, the package is unqualifiedly exported
CompilerStatisticsJVM -> CompilerCompiler Statistics
NameValue
threadfalse
periodeveryChunk
startTimefalse
NameTypeContentTypeLabel
compileCountintCompiled Methods
bailoutCountintBailouts
invalidatedCountintInvalidated Compilations
osrCompileCountintOSR Compilations
standardCompileCountintStandard Compilations
osrBytesCompiledulongbytesOSR Bytes Compiled
standardBytesCompiledulongbytesStandard Bytes Compiled
nmethodsSizeulongbytesCompilation Resulting Size
nmethodCodeSizeulongbytesCompilation Resulting Code Size
peakTimeSpentlongmillisPeak Time
totalTimeSpentlongmillisTotal time
CompilerConfigurationJVM -> CompilerCompiler Configuration
NameValue
threadfalse
periodendChunk
startTimefalse
NameTypeLabel
threadCountintThread Count
tieredCompilationbooleanTiered Compilation
CodeCacheStatisticsJVM -> Code CacheCode Cache Statistics
NameValue
threadfalse
periodeveryChunk
startTimefalse
NameTypeContentTypeLabel
codeBlobTypeCodeBlobTypeCode Heap
startAddressulongaddressStart Address
reservedTopAddressulongaddressReserved Top
entryCountintEntries
methodCountintMethods
adaptorCountintAdaptors
unallocatedCapacityulongbytesUnallocated
fullCountintFull Count
CodeCacheConfigurationJVM -> Code CacheCode Cache Configuration
NameValue
threadfalse
periodendChunk
startTimefalse
NameTypeContentTypeLabel
initialSizeulongbytesInitial Size
reservedSizeulongbytesReserved Size
nonNMethodSizeulongbytesNon-nmethod Size
profiledSizeulongbytesProfiled Size
nonProfiledSizeulongbytesNon-profiled Size
expansionSizeulongbytesExpansion size
minBlockLengthulongbytesMinimum Block Length
startAddressulongaddressStart Address
reservedTopAddressulongaddressReserved Top
CodeSweeperStatisticsJVM -> Code SweeperCode Sweeper Statistics
NameValue
threadfalse
periodeveryChunk
startTimefalse
NameTypeLabel
sweepCountintSweeps
methodReclaimedCountintMethods Reclaimed
totalSweepTimeTickspanTime Spent Sweeping
peakFractionTimeTickspanPeak Time Fraction Sweep
peakSweepTimeTickspanPeak Time Full Sweep
CodeSweeperConfigurationJVM -> Code SweeperCode Sweeper Configuration
NameValue
threadfalse
periodendChunk
startTimefalse
NameTypeContentTypeLabel
sweeperEnabledbooleanCode Sweeper Enabled
flushingEnabledbooleanCode Cache Flushing Enabled
sweepThresholdulongbytesSweep Threshold
IntFlagJVM -> FlagInt Flag
NameValue
periodendChunk
NameTypeLabel
namestringName
valueintValue
originFlagValueOriginOrigin
UnsignedIntFlagJVM -> FlagUnsigned Int Flag
NameValue
periodendChunk
NameTypeLabel
namestringName
valueuintValue
originFlagValueOriginOrigin
LongFlagJVM -> FlagLong Flag
NameValue
periodendChunk
NameTypeLabel
namestringName
valuelongValue
originFlagValueOriginOrigin
UnsignedLongFlagJVM -> FlagUnsigned Long Flag
NameValue
periodendChunk
NameTypeLabel
namestringName
valueulongValue
originFlagValueOriginOrigin
DoubleFlagJVM -> FlagDouble Flag
NameValue
periodendChunk
NameTypeLabel
namestringName
valuedoubleValue
originFlagValueOriginOrigin
BooleanFlagJVM -> FlagBoolean Flag
NameValue
periodendChunk
NameTypeLabel
namestringName
valuebooleanValue
originFlagValueOriginOrigin
StringFlagJVM -> FlagString Flag
NameValue
periodendChunk
NameTypeLabel
namestringName
valuestringValue
originFlagValueOriginOrigin
ObjectCountJVM -> GC -> DetailedObject Count
NameValue
startTimefalse
periodeveryChunk
NameTypeContentTypeLabel
gcIduintGC Identifier
objectClassClassObject Class
countlongCount
totalSizeulongbytesTotal Size
G1HeapRegionInformationJVM -> GC -> DetailedG1 Heap Region Information
NameValue
descriptionInformation about a specific heap region in the G1 GC
periodeveryChunk
NameTypeContentTypeLabel
indexuintIndex
typeG1HeapRegionTypeType
startulongaddressStart
usedulongbytesUsed
GCConfigurationJVM -> GC -> ConfigurationGC Configuration
NameValue
descriptionThe configuration of the garbage collector
periodendChunk
NameTypeContentTypeLabelDescription
youngCollectorGCNameYoung Garbage CollectorThe garbage collector used for the young generation
oldCollectorGCNameOld Garbage CollectorThe garbage collector used for the old generation
parallelGCThreadsuintParallel GC ThreadsNumber of parallel threads to use for garbage collection
concurrentGCThreadsuintConcurrent GC ThreadsNumber of concurrent threads to use for garbage collection
usesDynamicGCThreadsbooleanUses Dynamic GC ThreadsWhether a dynamic number of GC threads are used or not
isExplicitGCConcurrentbooleanConcurrent Explicit GCWhether System.gc() is concurrent or not
isExplicitGCDisabledbooleanDisabled Explicit GCWhether System.gc() will cause a garbage collection or not
pauseTargetlongmillisPause TargetTarget for GC pauses
gcTimeRatiouintGC Time RatioTarget for runtime vs garbage collection time
GCSurvivorConfigurationJVM -> GC -> ConfigurationGC Survivor Configuration
NameValue
descriptionThe configuration of the survivors of garbage collection
periodendChunk
NameTypeLabelDescription
maxTenuringThresholdubyteMaximum Tenuring ThresholdUpper limit for the age of how old objects to keep in the survivor area
initialTenuringThresholdubyteInitial Tenuring ThresholdInitial age limit for how old objects to keep in survivor area
GCTLABConfigurationJVM -> GC -> ConfigurationTLAB Configuration
NameValue
descriptionThe configuration of the Thread Local Allocation Buffers (TLABs)
periodendChunk
NameTypeContentTypeLabelDescription
usesTLABsbooleanTLABs UsedIf Thread Local Allocation Buffers (TLABs) are in use
minTLABSizeulongbytesMinimum TLAB Size
tlabRefillWasteLimitulongbytesTLAB Refill Waste Limit
GCHeapConfigurationJVM -> GC -> ConfigurationGC Heap Configuration
NameValue
descriptionThe configuration of the garbage collected heap
periodendChunk
NameTypeContentTypeLabelDescription
minSizeulongbytesMinimum Heap Size
maxSizeulongbytesMaximum Heap Size
initialSizeulongbytesInitial Heap Size
usesCompressedOopsbooleanIf Compressed Oops Are UsedIf compressed Oops (Ordinary Object Pointers) are enabled
compressedOopsModeNarrowOopModeCompressed Oops ModeThe kind of compressed oops being used
objectAlignmentulongbytesObject AlignmentObject alignment (in bytes) on the heap
heapAddressBitsubyteHeap Address SizeHeap Address Size (in bits)
YoungGenerationConfigurationJVM -> GC -> ConfigurationYoung Generation Configuration
NameValue
descriptionThe configuration of the young generation of the garbage collected heap
periodendChunk
NameTypeContentTypeLabelDescription
minSizeulongbytesMinimum Young Generation Size
maxSizeulongbytesMaximum Young Generation Size
newRatiouintNew RatioThe size of the young generation relative to the tenured generation
ZAllocationStallJVM -> GC -> DetailedZGC Allocation Stall
NameValue
descriptionTime spent waiting for memory to become available
threadtrue
NameTypeContentTypeLabel
typeZPageTypeTypeType
sizeulongbytesSize
ZPageAllocationJVM -> GC -> DetailedZGC Page Allocation
NameValue
descriptionAllocation of a ZPage
threadtrue
stackTracetrue
NameTypeContentTypeLabel
typeZPageTypeTypeType
sizeulongbytesSize
flushedulongbytesFlushed
committedulongbytesCommitted
segmentsuintSegments
nonBlockingbooleanNon-blocking
ZRelocationSetJVM -> GC -> DetailedZGC Relocation Set
NameValue
threadtrue
NameTypeContentTypeLabel
totalulongbytesTotal
emptyulongbytesEmpty
relocateulongbytesRelocate
ZRelocationSetGroupJVM -> GC -> DetailedZGC Relocation Set Group
NameValue
threadtrue
NameTypeContentTypeLabel
typeZPageTypeTypeType
pagesulongPages
totalulongbytesTotal
emptyulongbytesEmpty
relocateulongbytesRelocate
ZStatisticsCounterJVM -> GC -> DetailedZGC Statistics Counter
NameValue
threadtrue
experimentaltrue
NameTypeLabel
idZStatisticsCounterTypeId
incrementulongIncrement
valueulongValue
ZStatisticsSamplerJVM -> GC -> DetailedZGC Statistics Sampler
NameValue
threadtrue
experimentaltrue
NameTypeLabel
idZStatisticsSamplerTypeId
valueulongValue
ZThreadPhaseJVM -> GC -> DetailedZGC Thread Phase
NameValue
threadtrue
experimentaltrue
NameTypeLabel
gcIduintGC Identifier
namestringName
ZUncommitJVM -> GC -> DetailedZGC Uncommit
NameValue
descriptionUncommitting of memory
threadtrue
NameTypeContentTypeLabel
uncommittedulongbytesUncommitted
ZUnmapJVM -> GC -> DetailedZGC Unmap
NameValue
descriptionUnmapping of memory
threadtrue
NameTypeContentTypeLabel
unmappedulongbytesUnmapped
ShenandoahHeapRegionStateChangeJVM -> GC -> DetailedShenandoah Heap Region State Change
NameValue
descriptionInformation about a Shenandoah heap region state change
startTimefalse
NameTypeContentTypeLabel
indexuintIndex
fromShenandoahHeapRegionStateFrom
toShenandoahHeapRegionStateTo
startulongaddressStart
usedulongbytesUsed
ShenandoahHeapRegionInformationJVM -> GC -> DetailedShenandoah Heap Region Information
NameValue
descriptionInformation about a specific heap region in the Shenandoah GC
periodeveryChunk
NameTypeContentTypeLabel
indexuintIndex
stateShenandoahHeapRegionStateState
startulongaddressStart
usedulongbytesUsed
FlushFlight RecorderFlush
NameValue
threadfalse
experimentaltrue
NameTypeContentTypeLabel
flushIdulongFlush Identifier
elementsulongElements Written
sizeulongbytesSize Written
HeapDumpJVM -> DiagnosticsHeap Dump
NameValue
stackTracetrue
threadtrue
NameTypeLabel
destinationstringDestination
sizelongSize
gcBeforeDumpbooleanGC Before Dump
onOutOfMemoryErrorbooleanOn Out of Memory Error
GCLockerJVM -> GC -> DetailedGC Locker
NameValue
startTimetrue
threadtrue
stackTracetrue
NameTypeLabelDescription
lockCountuintLock CountThe number of Java threads in a critical section when the GC locker is started
stallCountuintStall CountThe number of Java threads stalled by the GC locker