Чтобы посмотреть, какие опции поддерживает ваша версия Java, запускаем:
java -showversion -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+PrintFlagsFinal
и получаем на экране полный список:
У меня на Java 14 получилось 806 опций:
java version "14" 2020-03-17
Java(TM) SE Runtime Environment (build 14+36-1461)
Java HotSpot(TM) 64-Bit Server VM (build 14+36-1461, mixed mode, sharing)
[Global flags]
ccstrlist AOTLibrary = {experimental} {default}
int AVX3Threshold = 4096 {ARCH diagnostic} {default}
bool AbortVMOnCompilationFailure = false {diagnostic} {default}
ccstr AbortVMOnException = {diagnostic} {default}
ccstr AbortVMOnExceptionMessage = {diagnostic} {default}
bool AbortVMOnSafepointTimeout = false {diagnostic} {default}
bool AbortVMOnVMOperationTimeout = false {diagnostic} {default}
intx AbortVMOnVMOperationTimeoutDelay = 1000 {diagnostic} {default}
int ActiveProcessorCount = -1 {product} {default}
uintx AdaptiveSizeDecrementScaleFactor = 4 {product} {default}
uintx AdaptiveSizeMajorGCDecayTimeScale = 10 {product} {default}
uintx AdaptiveSizePolicyCollectionCostMargin = 50 {product} {default}
uintx AdaptiveSizePolicyInitializingSteps = 20 {product} {default}
uintx AdaptiveSizePolicyOutputInterval = 0 {product} {default}
uintx AdaptiveSizePolicyWeight = 10 {product} {default}
uintx AdaptiveSizeThroughPutPolicy = 0 {product} {default}
uintx AdaptiveTimeWeight = 25 {product} {default}
bool AggressiveHeap = false {product} {default}
bool AggressiveUnboxing = true {C2 diagnostic} {default}
intx AliasLevel = 3 {C2 product} {default}
bool AlignVector = false {C2 product} {default}
ccstr AllocateHeapAt = {product} {default}
intx AllocateInstancePrefetchLines = 1 {product} {default}
ccstr AllocateOldGenAt = {experimental} {default}
intx AllocatePrefetchDistance = 256 {product} {default}
intx AllocatePrefetchInstr = 3 {product} {default}
intx AllocatePrefetchLines = 3 {product} {default}
intx AllocatePrefetchStepSize = 64 {product} {default}
intx AllocatePrefetchStyle = 1 {product} {default}
bool AllowArchivingWithJavaAgent = false {diagnostic} {default}
bool AllowParallelDefineClass = false {product} {default}
bool AllowRedefinitionToAddDeleteMethods = false {product} {default}
bool AllowUserSignalHandlers = false {product} {default}
bool AllowVectorizeOnDemand = true {C2 product} {default}
bool AlwaysActAsServerClassMachine = false {product} {default}
bool AlwaysAtomicAccesses = false {experimental} {default}
bool AlwaysCompileLoopMethods = false {product} {default}
bool AlwaysLockClassLoader = false {product} {default}
bool AlwaysPreTouch = false {product} {default}
bool AlwaysRestoreFPU = false {product} {default}
bool AlwaysSafeConstructors = false {experimental} {default}
bool AlwaysTenure = false {product} {default}
ccstr ArchiveClassesAtExit = {product} {default}
intx ArchiveRelocationMode = 0 {diagnostic} {default}
size_t ArrayAllocatorMallocLimit = 18446744073709551615 {experimental} {default}
intx ArrayCopyLoadStoreMaxElem = 8 {C2 product} {default}
bool AssertOnSuspendWaitFailure = false {product} {default}
intx AutoBoxCacheMax = 128 {C2 product} {default}
intx BCEATraceLevel = 0 {product} {default}
bool BackgroundCompilation = true {pd product} {default}
size_t BaseFootPrintEstimate = 268435456 {product} {default}
intx BiasedLockingBulkRebiasThreshold = 20 {product} {default}
intx BiasedLockingBulkRevokeThreshold = 40 {product} {default}
intx BiasedLockingDecayTime = 25000 {product} {default}
intx BiasedLockingStartupDelay = 0 {product} {default}
bool BlockLayoutByFrequency = true {C2 product} {default}
intx BlockLayoutMinDiamondPercentage = 20 {C2 product} {default}
bool BlockLayoutRotateLoops = true {C2 product} {default}
bool BootstrapJVMCI = false {JVMCI experimental} {default}
bool BranchOnRegister = false {C2 product} {default}
bool BytecodeVerificationLocal = false {diagnostic} {default}
bool BytecodeVerificationRemote = true {diagnostic} {default}
bool C1OptimizeVirtualCallProfiling = true {C1 product} {default}
bool C1ProfileBranches = true {C1 product} {default}
bool C1ProfileCalls = true {C1 product} {default}
bool C1ProfileCheckcasts = true {C1 product} {default}
bool C1ProfileInlinedCalls = true {C1 product} {default}
bool C1ProfileVirtualCalls = true {C1 product} {default}
bool C1UpdateMethodData = true {C1 product} {default}
intx CICompilerCount = 3 {product} {ergonomic}
bool CICompilerCountPerCPU = true {product} {default}
bool CIPrintCompileQueue = false {diagnostic} {default}
bool CITime = false {product} {default}
bool CalculateClassFingerprint = false {product} {default}
bool CheckIntrinsics = true {diagnostic} {default}
bool CheckJNICalls = false {product} {default}
bool ClassUnloading = true {product} {default}
bool ClassUnloadingWithConcurrentMark = true {product} {default}
bool ClipInlining = true {product} {default}
uintx CodeCacheExpansionSize = 65536 {pd product} {default}
uintx CodeCacheMinBlockLength = 6 {pd diagnostic} {default}
bool CompactFields = true {product} {default}
bool CompactStrings = true {pd product} {default}
ccstr CompilationMode = default {product} {default}
ccstrlist CompileCommand = {product} {default}
ccstr CompileCommandFile = {product} {default}
ccstrlist CompileOnly = {product} {default}
intx CompileThreshold = 10000 {pd product} {default}
double CompileThresholdScaling = 1.000000 {product} {default}
ccstr CompilerDirectivesFile = {diagnostic} {default}
bool CompilerDirectivesIgnoreCompileCommands = false {diagnostic} {default}
int CompilerDirectivesLimit = 50 {diagnostic} {default}
bool CompilerDirectivesPrint = false {diagnostic} {default}
intx CompilerThreadPriority = -1 {product} {default}
intx CompilerThreadStackSize = 0 {pd product} {default}
size_t CompressedClassSpaceSize = 1073741824 {product} {default}
uint ConcGCThreads = 1 {product} {ergonomic}
intx ConditionalMoveLimit = 3 {C2 pd product} {default}
intx ContendedPaddingWidth = 128 {product} {default}
bool CrashOnOutOfMemoryError = false {product} {default}
bool CreateCoredumpOnCrash = true {product} {default}
bool CriticalJNINatives = true {product} {default}
bool DTraceAllocProbes = false {product} {default}
bool DTraceMethodProbes = false {product} {default}
bool DTraceMonitorProbes = false {product} {default}
bool DebugInlinedCalls = true {C2 diagnostic} {default}
bool DebugNonSafepoints = false {diagnostic} {default}
bool Debugging = false {product} {default}
bool DeferInitialCardMark = false {diagnostic} {default}
bool DisableAttachMechanism = false {product} {default}
bool DisableExplicitGC = false {product} {default}
ccstrlist DisableIntrinsic = {diagnostic} {default}
bool DisablePrimordialThreadGuardPages = false {experimental} {default}
bool DisplayVMOutput = true {diagnostic} {default}
bool DisplayVMOutputToStderr = false {product} {default}
bool DisplayVMOutputToStdout = false {product} {default}
bool DoEscapeAnalysis = true {C2 product} {default}
bool DoReserveCopyInSuperWord = true {C2 product} {default}
intx DominatorSearchLimit = 1000 {C2 diagnostic} {default}
bool DontCompileHugeMethods = true {product} {default}
bool DontYieldALot = false {pd product} {default}
ccstr DumpLoadedClassList = {product} {default}
bool DumpReplayDataOnError = true {product} {default}
bool DumpSharedSpaces = false {product} {default}
bool DynamicDumpSharedSpaces = false {product} {default}
bool DynamicallyResizeSystemDictionaries = true {diagnostic} {default}
bool EagerJVMCI = false {JVMCI experimental} {default}
bool EagerXrunInit = false {product} {default}
intx EliminateAllocationArraySizeLimit = 64 {C2 product} {default}
bool EliminateAllocations = true {C2 product} {default}
bool EliminateAutoBox = true {C2 product} {default}
bool EliminateLocks = true {C2 product} {default}
bool EliminateNestedLocks = true {C2 product} {default}
bool EnableContended = true {product} {default}
bool EnableDynamicAgentLoading = true {product} {default}
bool EnableJVMCI = false {JVMCI experimental} {default}
bool EnableJVMCIProduct = false {JVMCI experimental} {default}
bool EnableThreadSMRExtraValidityChecks = true {diagnostic} {default}
bool EnableThreadSMRStatistics = false {diagnostic} {default}
bool EpsilonElasticTLAB = true {experimental} {default}
bool EpsilonElasticTLABDecay = true {experimental} {default}
size_t EpsilonMaxTLABSize = 4194304 {experimental} {default}
size_t EpsilonMinHeapExpand = 134217728 {experimental} {default}
size_t EpsilonPrintHeapSteps = 20 {experimental} {default}
size_t EpsilonTLABDecayTime = 1000 {experimental} {default}
double EpsilonTLABElasticity = 1.100000 {experimental} {default}
size_t EpsilonUpdateCountersStep = 1048576 {experimental} {default}
size_t ErgoHeapSizeLimit = 0 {product} {default}
ccstr ErrorFile = {product} {default}
bool ErrorFileToStderr = false {product} {default}
bool ErrorFileToStdout = false {product} {default}
uint64_t ErrorLogTimeout = 120 {product} {default}
double EscapeAnalysisTimeout = 20.000000 {C2 product} {default}
bool EstimateArgEscape = true {product} {default}
bool ExecutingUnitTests = false {product} {default}
bool ExitOnOutOfMemoryError = false {product} {default}
bool ExplicitGCInvokesConcurrent = false {product} {default}
bool ExtendedDTraceProbes = false {product} {default}
bool ExtensiveErrorReports = false {product} {default}
ccstr ExtraSharedClassListFile = {product} {default}
intx FieldsAllocationStyle = 1 {product} {default}
bool FilterSpuriousWakeups = true {product} {default}
bool FlightRecorder = false {product} {default}
ccstr FlightRecorderOptions = {product} {default}
bool FoldStableValues = true {diagnostic} {default}
bool ForceDynamicNumberOfGCThreads = false {diagnostic} {default}
bool ForceNUMA = false {product} {default}
bool ForceTimeHighResolution = false {product} {default}
bool ForceUnreachable = false {diagnostic} {default}
intx FreqInlineSize = 325 {pd product} {default}
size_t G1AdaptiveIHOPNumInitialSamples = 3 {experimental} {default}
double G1ConcMarkStepDurationMillis = 10.000000 {product} {default}
uintx G1ConcRSHotCardLimit = 4 {product} {default}
size_t G1ConcRSLogCacheSize = 10 {product} {default}
size_t G1ConcRefinementGreenZone = 0 {product} {default}
size_t G1ConcRefinementRedZone = 0 {product} {default}
uintx G1ConcRefinementServiceIntervalMillis = 300 {product} {default}
uint G1ConcRefinementThreads = 4 {product} {ergonomic}
size_t G1ConcRefinementThresholdStep = 2 {product} {default}
size_t G1ConcRefinementYellowZone = 0 {product} {default}
uintx G1ConfidencePercent = 50 {product} {default}
bool G1EagerReclaimHumongousObjects = true {experimental} {default}
bool G1EagerReclaimHumongousObjectsWithStaleRefs = true {experimental} {default}
intx G1ExpandByPercentOfAvailable = 20 {experimental} {default}
size_t G1HeapRegionSize = 1048576 {product} {ergonomic}
uintx G1HeapWastePercent = 5 {product} {default}
double G1LastPLABAverageOccupancy = 50.000000 {experimental} {default}
uintx G1MaxNewSizePercent = 60 {experimental} {default}
uintx G1MixedGCCountTarget = 8 {product} {default}
uintx G1MixedGCLiveThresholdPercent = 85 {experimental} {default}
uintx G1NewSizePercent = 5 {experimental} {default}
uintx G1OldCSetRegionThresholdPercent = 10 {experimental} {default}
uintx G1PeriodicGCInterval = 0 {manageable} {default}
bool G1PeriodicGCInvokesConcurrent = true {product} {default}
double G1PeriodicGCSystemLoadThreshold = 0.000000 {manageable} {default}
intx G1RSetRegionEntries = 256 {product} {default}
size_t G1RSetScanBlockSize = 64 {product} {default}
intx G1RSetSparseRegionEntries = 8 {product} {default}
intx G1RSetUpdatingPauseTimePercent = 10 {product} {default}
size_t G1RebuildRemSetChunkSize = 262144 {experimental} {default}
uint G1RefProcDrainInterval = 1000 {product} {default}
uintx G1ReservePercent = 10 {product} {default}
uintx G1SATBBufferEnqueueingThresholdPercent = 60 {product} {default}
size_t G1SATBBufferSize = 1024 {product} {default}
intx G1SummarizeRSetStatsPeriod = 0 {diagnostic} {default}
size_t G1UpdateBufferSize = 256 {product} {default}
bool G1UseAdaptiveConcRefinement = true {product} {default}
bool G1UseAdaptiveIHOP = true {product} {default}
bool G1UseReferencePrecleaning = true {experimental} {default}
bool G1VerifyHeapRegionCodeRoots = false {diagnostic} {default}
bool G1VerifyRSetsDuringFullGC = false {diagnostic} {default}
uintx G1YoungExpansionBufferPercent = 10 {experimental} {default}
uintx GCDrainStackTargetSize = 64 {product} {ergonomic}
uintx GCHeapFreeLimit = 2 {product} {default}
uintx GCLockerEdenExpansionPercent = 5 {product} {default}
uintx GCLockerRetryAllocationCount = 2 {diagnostic} {default}
bool GCParallelVerificationEnabled = true {diagnostic} {default}
uintx GCPauseIntervalMillis = 201 {product} {default}
uintx GCTimeLimit = 98 {product} {default}
uintx GCTimeRatio = 12 {product} {default}
intx GuaranteedSafepointInterval = 1000 {diagnostic} {default}
bool HandshakeALot = false {diagnostic} {default}
uint HandshakeTimeout = 0 {diagnostic} {default}
size_t HeapBaseMinAddress = 2147483648 {pd product} {default}
bool HeapDumpAfterFullGC = false {manageable} {default}
bool HeapDumpBeforeFullGC = false {manageable} {default}
bool HeapDumpOnOutOfMemoryError = false {manageable} {default}
ccstr HeapDumpPath = {manageable} {default}
uintx HeapFirstMaximumCompactionCount = 3 {product} {default}
uintx HeapMaximumCompactionInterval = 20 {product} {default}
uintx HeapSearchSteps = 3 {product} {default}
size_t HeapSizePerGCThread = 43620760 {product} {default}
intx HotMethodDetectionLimit = 100000 {diagnostic} {default}
bool IdealizeClearArrayNode = true {C2 pd diagnostic} {default}
bool IgnoreEmptyClassPaths = false {product} {default}
bool IgnoreUnrecognizedVMOptions = false {product} {default}
bool ImplicitNullChecks = true {pd diagnostic} {default}
uintx IncreaseFirstTierCompileThresholdAt = 50 {product} {default}
bool IncrementalInline = true {C2 product} {default}
intx InitArrayShortSize = 64 {pd diagnostic} {default}
size_t InitialBootClassLoaderMetaspaceSize = 4194304 {product} {default}
uintx InitialCodeCacheSize = 2555904 {pd product} {default}
size_t InitialHeapSize = 266338304 {product} {ergonomic}
uintx InitialRAMFraction = 64 {product} {default}
double InitialRAMPercentage = 1.562500 {product} {default}
uintx InitialSurvivorRatio = 8 {product} {default}
uintx InitialTenuringThreshold = 7 {product} {default}
uintx InitiatingHeapOccupancyPercent = 45 {product} {default}
bool InjectGCWorkerCreationFailure = false {diagnostic} {default}
bool Inline = true {product} {default}
bool InlineArrayCopy = true {diagnostic} {default}
bool InlineClassNatives = true {diagnostic} {default}
ccstr InlineDataFile = {product} {default}
intx InlineFrequencyCount = 100 {pd diagnostic} {default}
bool InlineMathNatives = true {diagnostic} {default}
bool InlineNIOCheckIndex = true {C1 diagnostic} {default}
bool InlineNatives = true {diagnostic} {default}
bool InlineObjectCopy = true {C2 diagnostic} {default}
bool InlineObjectHash = true {diagnostic} {default}
bool InlineReflectionGetCallerClass = true {C2 diagnostic} {default}
intx InlineSmallCode = 2000 {pd product} {default}
bool InlineSynchronizedMethods = true {C1 product} {default}
bool InlineThreadNatives = true {diagnostic} {default}
bool InlineUnsafeOps = true {diagnostic} {default}
bool InsertMemBarAfterArraycopy = true {C2 product} {default}
intx InteriorEntryAlignment = 16 {C2 pd product} {default}
intx InterpreterProfilePercentage = 33 {product} {default}
intx JVMCICounterSize = 0 {JVMCI experimental} {default}
bool JVMCICountersExcludeCompiler = true {JVMCI experimental} {default}
intx JVMCIHostThreads = 1 {JVMCI experimental} {default}
ccstr JVMCILibDumpJNIConfig = {JVMCI experimental} {default}
ccstr JVMCILibPath = {JVMCI experimental} {default}
intx JVMCINMethodSizeLimit = 655360 {JVMCI experimental} {default}
bool JVMCIPrintProperties = false {JVMCI experimental} {default}
intx JVMCIThreads = 1 {JVMCI experimental} {default}
intx JVMCITraceLevel = 0 {JVMCI experimental} {default}
bool JavaMonitorsInStackTrace = true {product} {default}
intx JavaPriority10_To_OSPriority = -1 {product} {default}
intx JavaPriority1_To_OSPriority = -1 {product} {default}
intx JavaPriority2_To_OSPriority = -1 {product} {default}
intx JavaPriority3_To_OSPriority = -1 {product} {default}
intx JavaPriority4_To_OSPriority = -1 {product} {default}
intx JavaPriority5_To_OSPriority = -1 {product} {default}
intx JavaPriority6_To_OSPriority = -1 {product} {default}
intx JavaPriority7_To_OSPriority = -1 {product} {default}
intx JavaPriority8_To_OSPriority = -1 {product} {default}
intx JavaPriority9_To_OSPriority = -1 {product} {default}
bool LIRFillDelaySlots = false {C1 pd product} {default}
size_t LargePageHeapSizeThreshold = 134217728 {product} {default}
size_t LargePageSizeInBytes = 0 {product} {default}
intx LiveNodeCountInliningCutoff = 40000 {C2 product} {default}
bool LogCompilation = false {diagnostic} {default}
bool LogEvents = true {diagnostic} {default}
uintx LogEventsBufferEntries = 20 {diagnostic} {default}
ccstr LogFile = {diagnostic} {default}
bool LogTouchedMethods = false {diagnostic} {default}
bool LogVMOutput = false {diagnostic} {default}
intx LoopMaxUnroll = 16 {C2 product} {default}
intx LoopOptsCount = 43 {C2 product} {default}
intx LoopPercentProfileLimit = 30 {C2 pd product} {default}
uintx LoopStripMiningIter = 1000 {C2 product} {default}
uintx LoopStripMiningIterShortLoop = 100 {C2 product} {default}
intx LoopUnrollLimit = 60 {C2 pd product} {default}
intx LoopUnrollMin = 4 {C2 product} {default}
bool LoopUnswitching = true {C2 product} {default}
uintx MallocMaxTestWords = 0 {diagnostic} {default}
bool ManagementServer = false {product} {default}
size_t MarkStackSize = 4194304 {product} {ergonomic}
size_t MarkStackSizeMax = 16777216 {product} {default}
uint MarkSweepAlwaysCompactCount = 4 {product} {default}
uintx MarkSweepDeadRatio = 5 {product} {default}
intx MaxBCEAEstimateLevel = 5 {product} {default}
intx MaxBCEAEstimateSize = 150 {product} {default}
uint64_t MaxDirectMemorySize = 0 {product} {default}
bool MaxFDLimit = true {product} {default}
uintx MaxGCMinorPauseMillis = 18446744073709551615 {product} {default}
uintx MaxGCPauseMillis = 200 {product} {default}
uintx MaxHeapFreeRatio = 70 {manageable} {default}
size_t MaxHeapSize = 4259315712 {product} {ergonomic}
intx MaxInlineLevel = 15 {product} {default}
intx MaxInlineSize = 35 {product} {default}
intx MaxJNILocalCapacity = 65536 {product} {default}
intx MaxJavaStackTraceDepth = 1024 {product} {default}
intx MaxJumpTableSize = 65000 {C2 product} {default}
intx MaxJumpTableSparseness = 5 {C2 product} {default}
intx MaxLabelRootDepth = 1100 {C2 product} {default}
intx MaxLoopPad = 11 {C2 product} {default}
size_t MaxMetaspaceExpansion = 5451776 {product} {default}
uintx MaxMetaspaceFreeRatio = 70 {product} {default}
size_t MaxMetaspaceSize = 18446744073709486080 {product} {default}
size_t MaxNewSize = 2555379712 {product} {ergonomic}
intx MaxNodeLimit = 80000 {C2 product} {default}
uint64_t MaxRAM = 137438953472 {pd product} {default}
uintx MaxRAMFraction = 4 {product} {default}
double MaxRAMPercentage = 25.000000 {product} {default}
intx MaxRecursiveInlineLevel = 1 {product} {default}
uintx MaxTenuringThreshold = 15 {product} {default}
intx MaxTrivialSize = 6 {product} {default}
intx MaxVectorSize = 32 {C2 product} {default}
size_t MetaspaceSize = 21807104 {pd product} {default}
bool MethodFlushing = true {product} {default}
intx MethodProfileWidth = 0 {JVMCI experimental} {default}
size_t MinHeapDeltaBytes = 1048576 {product} {ergonomic}
uintx MinHeapFreeRatio = 40 {manageable} {default}
size_t MinHeapSize = 8388608 {product} {ergonomic}
intx MinInliningThreshold = 250 {product} {default}
intx MinJumpTableSize = 10 {C2 pd product} {default}
size_t MinMetaspaceExpansion = 339968 {product} {default}
uintx MinMetaspaceFreeRatio = 40 {product} {default}
intx MinPassesBeforeFlush = 10 {diagnostic} {default}
uintx MinRAMFraction = 2 {product} {default}
double MinRAMPercentage = 50.000000 {product} {default}
uintx MinSurvivorRatio = 3 {product} {default}
size_t MinTLABSize = 2048 {product} {default}
intx MonitorBound = 0 {product} {default}
intx MonitorUsedDeflationThreshold = 90 {experimental} {default}
intx MultiArrayExpandLimit = 6 {C2 product} {default}
uintx NUMAChunkResizeWeight = 20 {product} {default}
size_t NUMAInterleaveGranularity = 2097152 {product} {default}
uintx NUMAPageScanRate = 256 {product} {default}
size_t NUMASpaceResizeRate = 1073741824 {product} {default}
bool NUMAStats = false {product} {default}
ccstr NativeMemoryTracking = off {product} {default}
bool NeverActAsServerClassMachine = false {pd product} {default}
bool NeverTenure = false {product} {default}
uintx NewRatio = 2 {product} {default}
size_t NewSize = 1363144 {product} {default}
size_t NewSizeThreadIncrease = 5320 {pd product} {default}
intx NmethodSweepActivity = 10 {product} {default}
intx NodeLimitFudgeFactor = 2000 {C2 product} {default}
uintx NonNMethodCodeHeapSize = 5832780 {pd product} {ergonomic}
uintx NonProfiledCodeHeapSize = 122912730 {pd product} {ergonomic}
intx NumberOfLoopInstrToAlign = 4 {C2 product} {default}
intx ObjectAlignmentInBytes = 8 {lp64_product} {default}
double ObjectCountCutOffPercent = 0.500000 {experimental} {default}
size_t OldPLABSize = 1024 {product} {default}
size_t OldSize = 5452592 {product} {default}
bool OmitStackTraceInFastThrow = true {product} {default}
ccstrlist OnError = {product} {default}
ccstrlist OnOutOfMemoryError = {product} {default}
intx OnStackReplacePercentage = 140 {pd product} {default}
bool OptimizeExpensiveOps = true {C2 diagnostic} {default}
bool OptimizeFill = true {C2 product} {default}
bool OptimizePtrCompare = true {C2 product} {default}
bool OptimizeStringConcat = true {C2 product} {default}
bool OptoBundling = false {C2 pd product} {default}
intx OptoLoopAlignment = 16 {pd product} {default}
bool OptoRegScheduling = true {C2 pd product} {default}
bool OptoScheduling = false {C2 pd product} {default}
uintx PLABWeight = 75 {product} {default}
bool PSChunkLargeArrays = true {product} {default}
int ParGCArrayScanChunk = 50 {product} {default}
uintx ParallelGCBufferWastePct = 10 {product} {default}
uint ParallelGCThreads = 4 {product} {default}
size_t ParallelOldDeadWoodLimiterMean = 50 {product} {default}
size_t ParallelOldDeadWoodLimiterStdDev = 80 {product} {default}
bool ParallelRefProcBalancingEnabled = true {product} {default}
bool ParallelRefProcEnabled = true {product} {default}
bool PartialPeelAtUnsignedTests = true {C2 product} {default}
bool PartialPeelLoop = true {C2 product} {default}
intx PartialPeelNewPhiDelta = 0 {C2 product} {default}
bool PauseAtExit = false {diagnostic} {default}
bool PauseAtStartup = false {diagnostic} {default}
ccstr PauseAtStartupFile = {diagnostic} {default}
uintx PausePadding = 1 {product} {default}
intx PerBytecodeRecompilationCutoff = 200 {product} {default}
intx PerBytecodeTrapLimit = 4 {product} {default}
intx PerMethodRecompilationCutoff = 400 {product} {default}
intx PerMethodSpecTrapLimit = 5000 {experimental} {default}
intx PerMethodTrapLimit = 100 {product} {default}
bool PerfAllowAtExitRegistration = false {product} {default}
bool PerfBypassFileSystemCheck = false {product} {default}
intx PerfDataMemorySize = 32768 {product} {default}
intx PerfDataSamplingInterval = 50 {product} {default}
ccstr PerfDataSaveFile = {product} {default}
bool PerfDataSaveToFile = false {product} {default}
bool PerfDisableSharedMem = false {product} {default}
intx PerfMaxStringConstLength = 1024 {product} {default}
bool PostLoopMultiversioning = false {C2 experimental} {default}
size_t PreTouchParallelChunkSize = 1073741824 {product} {default}
bool PreferInterpreterNativeStubs = false {pd product} {default}
intx PrefetchCopyIntervalInBytes = 576 {product} {default}
intx PrefetchFieldsAhead = 1 {product} {default}
intx PrefetchScanIntervalInBytes = 576 {product} {default}
bool PreserveAllAnnotations = false {product} {default}
bool PreserveFramePointer = false {pd product} {default}
size_t PretenureSizeThreshold = 0 {product} {default}
bool PrintAOT = false {experimental} {default}
bool PrintAdapterHandlers = false {diagnostic} {default}
bool PrintAssembly = false {diagnostic} {default}
ccstr PrintAssemblyOptions = {diagnostic} {default}
bool PrintBiasedLockingStatistics = false {diagnostic} {default}
bool PrintBootstrap = true {JVMCI experimental} {default}
bool PrintClassHistogram = false {manageable} {default}
bool PrintCodeCache = false {product} {default}
bool PrintCodeCacheOnCompilation = false {product} {default}
bool PrintCodeHeapAnalytics = false {diagnostic} {default}
bool PrintCommandLineFlags = false {product} {default}
bool PrintCompilation = false {product} {default}
bool PrintCompilation2 = false {diagnostic} {default}
bool PrintConcurrentLocks = false {manageable} {default}
bool PrintExtendedThreadInfo = false {product} {default}
bool PrintFlagsFinal = true {product} {command line}
bool PrintFlagsInitial = false {product} {default}
bool PrintFlagsRanges = false {product} {default}
bool PrintGC = false {product} {default}
bool PrintGCDetails = false {product} {default}
bool PrintHeapAtSIGBREAK = true {product} {default}
bool PrintInlining = false {diagnostic} {default}
bool PrintInterpreter = false {diagnostic} {default}
bool PrintIntrinsics = false {C2 diagnostic} {default}
bool PrintMethodData = false {diagnostic} {default}
bool PrintMethodFlushingStatistics = false {diagnostic} {default}
bool PrintMethodHandleStubs = false {diagnostic} {default}
bool PrintNMTStatistics = false {diagnostic} {default}
bool PrintNMethods = false {diagnostic} {default}
bool PrintNativeNMethods = false {diagnostic} {default}
bool PrintOptoAssembly = false {C2 diagnostic} {default}
bool PrintPreciseBiasedLockingStatistics = false {C2 diagnostic} {default}
bool PrintPreciseRTMLockingStatistics = false {C2 diagnostic} {default}
bool PrintSharedArchiveAndExit = false {product} {default}
bool PrintSharedDictionary = false {product} {default}
bool PrintSignatureHandlers = false {diagnostic} {default}
bool PrintStringTableStatistics = false {product} {default}
bool PrintStubCode = false {diagnostic} {default}
bool PrintTieredEvents = false {product} {default}
bool PrintTouchedMethodsAtExit = false {diagnostic} {default}
bool PrintVMOptions = false {product} {default}
bool PrintVMQWaitTime = false {product} {default}
bool PrintWarnings = true {product} {default}
uintx ProcessDistributionStride = 4 {product} {default}
bool ProfileDynamicTypes = true {C2 diagnostic} {default}
bool ProfileInterpreter = true {pd product} {default}
intx ProfileMaturityPercentage = 20 {product} {default}
uintx ProfiledCodeHeapSize = 122912730 {pd product} {ergonomic}
uintx PromotedPadding = 3 {product} {default}
uintx QueuedAllocationWarningCount = 0 {product} {default}
int RTMAbortRatio = 50 {ARCH experimental} {default}
int RTMAbortThreshold = 1000 {ARCH experimental} {default}
intx RTMLockingCalculationDelay = 0 {ARCH experimental} {default}
int RTMLockingThreshold = 10000 {ARCH experimental} {default}
int RTMRetryCount = 5 {ARCH product} {default}
int RTMSpinLoopCount = 100 {ARCH experimental} {default}
int RTMTotalCountIncrRate = 64 {ARCH experimental} {default}
bool RangeCheckElimination = true {product} {default}
bool ReassociateInvariants = true {C2 product} {default}
bool ReduceBulkZeroing = true {C2 product} {default}
bool ReduceFieldZeroing = true {C2 product} {default}
bool ReduceInitialCardMarks = true {C2 product} {default}
bool ReduceNumberOfCompilerThreads = true {diagnostic} {default}
bool ReduceSignalUsage = false {product} {default}
intx RefDiscoveryPolicy = 0 {product} {default}
size_t ReferencesPerThread = 1000 {experimental} {default}
bool RegisterFinalizersAtInit = true {product} {default}
bool RelaxAccessControlCheck = false {product} {default}
ccstr ReplayDataFile = {product} {default}
bool RequireSharedSpaces = false {product} {default}
uintx ReservedCodeCacheSize = 251658240 {pd product} {ergonomic}
bool ResizePLAB = true {product} {default}
bool ResizeTLAB = true {pd product} {default}
bool RestoreMXCSROnJNICalls = false {product} {default}
bool RestrictContended = true {product} {default}
bool RestrictReservedStack = true {product} {default}
bool RewriteBytecodes = true {pd product} {default}
bool RewriteFrequentPairs = true {pd product} {default}
bool SafepointALot = false {diagnostic} {default}
bool SafepointTimeout = false {product} {default}
intx SafepointTimeoutDelay = 10000 {product} {default}
bool ScavengeBeforeFullGC = false {product} {default}
intx ScavengeRootsInCode = 2 {diagnostic} {default}
bool SegmentedCodeCache = true {product} {ergonomic}
intx SelfDestructTimer = 0 {product} {default}
bool SerializeVMOutput = true {diagnostic} {default}
ccstr SharedArchiveConfigFile = {product} {default}
ccstr SharedArchiveFile = {product} {default}
size_t SharedBaseAddress = 34359738368 {product} {default}
ccstr SharedClassListFile = {product} {default}
uintx SharedSymbolTableBucketSize = 4 {product} {default}
bool ShowCodeDetailsInExceptionMessages = false {manageable} {default}
bool ShowHiddenFrames = false {diagnostic} {default}
bool ShowMessageBoxOnError = false {product} {default}
bool ShowRegistersOnAssert = false {diagnostic} {default}
bool ShrinkHeapInSteps = true {product} {default}
size_t SoftMaxHeapSize = 4259315712 {manageable} {ergonomic}
intx SoftRefLRUPolicyMSPerMB = 1000 {product} {default}
intx SpecTrapLimitExtraEntries = 3 {experimental} {default}
bool SpecialArraysEquals = true {C2 diagnostic} {default}
bool SpecialEncodeISOArray = true {C2 diagnostic} {default}
bool SpecialStringCompareTo = true {C2 diagnostic} {default}
bool SpecialStringEquals = true {C2 diagnostic} {default}
bool SpecialStringIndexOf = true {C2 diagnostic} {default}
bool SplitIfBlocks = true {C2 product} {default}
intx StackRedPages = 1 {pd product} {default}
intx StackReservedPages = 0 {pd product} {default}
intx StackShadowPages = 7 {pd product} {default}
bool StackTraceInThrowable = true {product} {default}
intx StackYellowPages = 3 {pd product} {default}
uintx StartAggressiveSweepingAt = 10 {product} {default}
bool StartAttachListener = false {product} {default}
ccstr StartFlightRecording = {product} {default}
bool StressCodeAging = false {diagnostic} {default}
bool StressGCM = false {C2 diagnostic} {default}
bool StressLCM = false {C2 diagnostic} {default}
bool StressLdcRewrite = false {product} {default}
uintx StringDeduplicationAgeThreshold = 3 {product} {default}
bool StringDeduplicationRehashALot = false {diagnostic} {default}
bool StringDeduplicationResizeALot = false {diagnostic} {default}
uintx StringTableSize = 65536 {product} {default}
bool SuperWordLoopUnrollAnalysis = true {C2 pd product} {default}
bool SuperWordReductions = true {C2 product} {default}
bool SuppressFatalErrorMessage = false {product} {default}
intx SurvivorAlignmentInBytes = 8 {experimental} {default}
uintx SurvivorPadding = 3 {product} {default}
uintx SurvivorRatio = 8 {product} {default}
intx SuspendRetryCount = 50 {product} {default}
intx SuspendRetryDelay = 5 {product} {default}
uintx SymbolTableSize = 32768 {experimental} {default}
uintx TLABAllocationWeight = 35 {product} {default}
uintx TLABRefillWasteFraction = 64 {product} {default}
size_t TLABSize = 0 {product} {default}
bool TLABStats = true {product} {default}
uintx TLABWasteIncrement = 4 {product} {default}
uintx TLABWasteTargetPercent = 1 {product} {default}
uintx TargetPLABWastePct = 10 {product} {default}
uintx TargetSurvivorRatio = 50 {product} {default}
uintx TenuredGenerationSizeIncrement = 20 {product} {default}
uintx TenuredGenerationSizeSupplement = 80 {product} {default}
uintx TenuredGenerationSizeSupplementDecay = 2 {product} {default}
intx ThreadPriorityPolicy = 0 {product} {default}
bool ThreadPriorityVerbose = false {product} {default}
intx ThreadStackSize = 0 {pd product} {default}
uintx ThresholdTolerance = 10 {product} {default}
intx Tier0AOTBackEdgeThreshold = 60000 {diagnostic} {default}
intx Tier0AOTCompileThreshold = 2000 {diagnostic} {default}
intx Tier0AOTInvocationThreshold = 200 {diagnostic} {default}
intx Tier0AOTMinInvocationThreshold = 100 {diagnostic} {default}
intx Tier0BackedgeNotifyFreqLog = 10 {product} {default}
intx Tier0Delay = 5 {diagnostic} {default}
intx Tier0InvokeNotifyFreqLog = 7 {product} {default}
intx Tier0ProfilingStartPercentage = 200 {product} {default}
intx Tier23InlineeNotifyFreqLog = 20 {product} {default}
intx Tier2BackEdgeThreshold = 0 {product} {default}
intx Tier2BackedgeNotifyFreqLog = 14 {product} {default}
intx Tier2CompileThreshold = 0 {product} {default}
intx Tier2InvokeNotifyFreqLog = 11 {product} {default}
intx Tier3AOTBackEdgeThreshold = 120000 {product} {default}
intx Tier3AOTCompileThreshold = 15000 {product} {default}
intx Tier3AOTInvocationThreshold = 10000 {product} {default}
intx Tier3AOTMinInvocationThreshold = 1000 {product} {default}
intx Tier3BackEdgeThreshold = 60000 {product} {default}
intx Tier3BackedgeNotifyFreqLog = 13 {product} {default}
intx Tier3CompileThreshold = 2000 {product} {default}
intx Tier3DelayOff = 2 {product} {default}
intx Tier3DelayOn = 5 {product} {default}
intx Tier3InvocationThreshold = 200 {product} {default}
intx Tier3InvokeNotifyFreqLog = 10 {product} {default}
intx Tier3LoadFeedback = 5 {product} {default}
intx Tier3MinInvocationThreshold = 100 {product} {default}
intx Tier40BackEdgeThreshold = 15000 {diagnostic} {default}
intx Tier40CompileThreshold = 10000 {diagnostic} {default}
intx Tier40InvocationThreshold = 5000 {diagnostic} {default}
intx Tier40MinInvocationThreshold = 600 {diagnostic} {default}
intx Tier4BackEdgeThreshold = 40000 {product} {default}
intx Tier4CompileThreshold = 15000 {product} {default}
intx Tier4InvocationThreshold = 5000 {product} {default}
intx Tier4LoadFeedback = 3 {product} {default}
intx Tier4MinInvocationThreshold = 600 {product} {default}
bool TieredCompilation = true {pd product} {default}
intx TieredCompileTaskTimeout = 50 {product} {default}
intx TieredRateUpdateMaxTime = 25 {product} {default}
intx TieredRateUpdateMinTime = 1 {product} {default}
intx TieredStopAtLevel = 4 {product} {default}
bool TimeLinearScan = false {C1 product} {default}
bool TraceCompilerThreads = false {diagnostic} {default}
ccstr TraceJVMTI = {product} {default}
bool TraceJVMTIObjectTagging = false {diagnostic} {default}
bool TraceSpilling = false {C2 diagnostic} {default}
bool TraceSuspendWaitFailures = false {product} {default}
bool TraceTypeProfile = false {C2 diagnostic} {default}
intx TrackedInitializationLimit = 50 {C2 product} {default}
bool TrapBasedNullChecks = false {pd product} {default}
bool TrapBasedRangeChecks = false {C2 pd product} {default}
bool TrustFinalNonStaticFields = false {experimental} {default}
intx TypeProfileArgsLimit = 2 {product} {default}
uintx TypeProfileLevel = 111 {pd product} {default}
intx TypeProfileMajorReceiverPercent = 90 {C2 product} {default}
intx TypeProfileParmsLimit = 2 {product} {default}
intx TypeProfileWidth = 2 {product} {default}
intx UnguardOnExecutionViolation = 0 {product} {default}
bool UnlockDiagnosticVMOptions = true {diagnostic} {command line}
bool UnlockExperimentalVMOptions = true {experimental} {command line}
bool UseAES = true {product} {default}
bool UseAESCTRIntrinsics = true {diagnostic} {default}
bool UseAESIntrinsics = true {diagnostic} {default}
bool UseAOT = false {experimental} {default}
bool UseAOTStrictLoading = false {diagnostic} {default}
intx UseAVX = 2 {ARCH product} {default}
bool UseAdaptiveGCBoundary = false {product} {default}
bool UseAdaptiveGenerationSizePolicyAtMajorCollection = true {product} {default}
bool UseAdaptiveGenerationSizePolicyAtMinorCollection = true {product} {default}
bool UseAdaptiveNUMAChunkSizing = true {product} {default}
bool UseAdaptiveSizeDecayMajorGCCost = true {product} {default}
bool UseAdaptiveSizePolicy = true {product} {default}
bool UseAdaptiveSizePolicyFootprintGoal = true {product} {default}
bool UseAdaptiveSizePolicyWithSystemGC = false {product} {default}
bool UseAddressNop = true {ARCH product} {default}
bool UseAdler32Intrinsics = false {diagnostic} {default}
bool UseBASE64Intrinsics = false {product} {default}
bool UseBMI1Instructions = true {ARCH product} {default}
bool UseBMI2Instructions = true {ARCH product} {default}
bool UseBiasedLocking = true {product} {default}
bool UseBimorphicInlining = true {C2 product} {default}
int UseBootstrapCallInfo = 1 {diagnostic} {default}
bool UseCLMUL = true {ARCH product} {default}
bool UseCMoveUnconditionally = false {C2 product} {default}
bool UseCRC32CIntrinsics = true {diagnostic} {default}
bool UseCRC32Intrinsics = true {diagnostic} {default}
bool UseCharacterCompareIntrinsics = false {C2 diagnostic} {default}
bool UseCodeAging = true {product} {default}
bool UseCodeCacheFlushing = true {product} {default}
bool UseCompiler = true {product} {default}
bool UseCompressedClassPointers = true {lp64_product} {ergonomic}
bool UseCompressedOops = true {lp64_product} {ergonomic}
bool UseCondCardMark = false {product} {default}
bool UseCountLeadingZerosInstruction = true {ARCH product} {default}
bool UseCountTrailingZerosInstruction = true {ARCH product} {default}
bool UseCountedLoopSafepoints = true {C2 product} {default}
bool UseCounterDecay = true {product} {default}
bool UseCriticalCompilerThreadPriority = false {experimental} {default}
bool UseCriticalJavaThreadPriority = false {experimental} {default}
bool UseDivMod = true {C2 product} {default}
bool UseDynamicNumberOfCompilerThreads = true {product} {default}
bool UseDynamicNumberOfGCThreads = true {product} {default}
bool UseEpsilonGC = false {experimental} {default}
bool UseFMA = true {product} {default}
bool UseFPUForSpilling = true {C2 product} {default}
bool UseFastJNIAccessors = true {product} {default}
bool UseFastStosb = true {ARCH product} {default}
bool UseFastUnorderedTimeStamps = false {experimental} {default}
bool UseG1GC = true {product} {ergonomic}
bool UseGCOverheadLimit = true {product} {default}
bool UseGHASHIntrinsics = true {diagnostic} {default}
bool UseHeavyMonitors = false {product} {default}
bool UseIncDec = true {ARCH diagnostic} {default}
bool UseInlineCaches = true {product} {default}
bool UseInlineDepthForSpeculativeTypes = true {C2 diagnostic} {default}
bool UseInterpreter = true {product} {default}
bool UseJVMCICompiler = false {JVMCI experimental} {default}
bool UseJVMCINativeLibrary = false {JVMCI experimental} {default}
bool UseJumpTables = true {C2 product} {default}
bool UseLWPSynchronization = true {product} {default}
bool UseLargePages = false {pd product} {default}
bool UseLargePagesInMetaspace = false {product} {default}
bool UseLargePagesIndividualAllocation = false {pd product} {ergonomic}
bool UseLibmIntrinsic = true {ARCH diagnostic} {default}
bool UseLoopCounter = true {product} {default}
bool UseLoopInvariantCodeMotion = true {C1 product} {default}
bool UseLoopPredicate = true {C2 product} {default}
bool UseMathExactIntrinsics = true {C2 diagnostic} {default}
bool UseMaximumCompactionOnSystemGC = true {product} {default}
bool UseMontgomeryMultiplyIntrinsic = true {C2 diagnostic} {default}
bool UseMontgomerySquareIntrinsic = true {C2 diagnostic} {default}
bool UseMulAddIntrinsic = true {C2 diagnostic} {default}
bool UseMultiplyToLenIntrinsic = true {C2 diagnostic} {default}
bool UseNUMA = false {product} {default}
bool UseNUMAInterleaving = false {product} {default}
bool UseNewCode = false {diagnostic} {default}
bool UseNewCode2 = false {diagnostic} {default}
bool UseNewCode3 = false {diagnostic} {default}
bool UseNewLongLShift = false {ARCH product} {default}
bool UseNotificationThread = true {product} {default}
bool UseOSErrorReporting = false {pd product} {default}
bool UseOWSTTaskTerminator = true {diagnostic} {default}
bool UseOnStackReplacement = true {pd product} {default}
bool UseOnlyInlinedBimorphic = true {C2 product} {default}
bool UseOptoBiasInlining = true {C2 product} {default}
bool UsePSAdaptiveSurvivorSizePolicy = true {product} {default}
bool UseParallelGC = false {product} {default}
bool UseParallelOldGC = false {product} {default}
bool UsePerfData = true {product} {default}
bool UsePopCountInstruction = true {product} {default}
bool UseProfiledLoopPredicate = true {C2 product} {default}
bool UseRDPCForConstantTableBase = false {C2 product} {default}
bool UseRTMDeopt = false {ARCH product} {default}
bool UseRTMForStackLocks = false {ARCH experimental} {default}
bool UseRTMLocking = false {ARCH product} {default}
bool UseRTMXendForLockBusy = true {ARCH experimental} {default}
bool UseSHA = true {product} {default}
bool UseSHA1Intrinsics = false {diagnostic} {default}
bool UseSHA256Intrinsics = true {diagnostic} {default}
bool UseSHA512Intrinsics = true {diagnostic} {default}
intx UseSSE = 4 {product} {default}
bool UseSSE42Intrinsics = true {ARCH product} {default}
bool UseSemaphoreGCThreadsSynchronization = true {diagnostic} {default}
bool UseSerialGC = false {product} {default}
bool UseSharedSpaces = true {product} {default}
bool UseShenandoahGC = false {experimental} {default}
bool UseSignalChaining = true {product} {default}
bool UseSquareToLenIntrinsic = true {C2 diagnostic} {default}
bool UseStoreImmI16 = false {ARCH product} {default}
bool UseStringDeduplication = false {product} {default}
bool UseSubwordForMaxVector = true {C2 product} {default}
bool UseSuperWord = true {C2 product} {default}
bool UseSwitchProfiling = true {diagnostic} {default}
bool UseTLAB = true {pd product} {default}
bool UseThreadPriorities = true {pd product} {default}
bool UseTypeProfile = true {product} {default}
bool UseTypeSpeculation = true {C2 product} {default}
bool UseUnalignedAccesses = true {diagnostic} {default}
bool UseUnalignedLoadStores = true {ARCH product} {default}
bool UseVectorCmov = false {C2 product} {default}
bool UseVectorizedMismatchIntrinsic = true {diagnostic} {default}
bool UseXMMForArrayCopy = true {product} {default}
bool UseXMMForObjInit = false {ARCH product} {default}
bool UseXmmI2D = false {ARCH product} {default}
bool UseXmmI2F = false {ARCH product} {default}
bool UseXmmLoadAndClearUpper = true {ARCH product} {default}
bool UseXmmRegToRegMoveAll = true {ARCH product} {default}
bool UseZGC = false {experimental} {default}
intx VMThreadPriority = -1 {product} {default}
intx VMThreadStackSize = 0 {pd product} {default}
intx ValueMapInitialSize = 11 {C1 product} {default}
intx ValueMapMaxLoopSize = 8 {C1 product} {default}
intx ValueSearchLimit = 1000 {C2 product} {default}
bool VerifyAdapterCalls = false {diagnostic} {default}
bool VerifyAfterGC = false {diagnostic} {default}
bool VerifyBeforeExit = false {diagnostic} {default}
bool VerifyBeforeGC = false {diagnostic} {default}
bool VerifyBeforeIteration = false {diagnostic} {default}
bool VerifyDuringGC = false {diagnostic} {default}
bool VerifyDuringStartup = false {diagnostic} {default}
intx VerifyGCLevel = 0 {diagnostic} {default}
uintx VerifyGCStartAt = 0 {diagnostic} {default}
ccstrlist VerifyGCType = {diagnostic} {default}
bool VerifyMergedCPBytecodes = true {product} {default}
bool VerifyMethodHandles = false {diagnostic} {default}
bool VerifyObjectStartArray = true {diagnostic} {default}
bool VerifyRememberedSets = false {diagnostic} {default}
bool VerifySharedSpaces = false {product} {default}
bool VerifyStringTableAtExit = false {diagnostic} {default}
ccstrlist VerifySubSet = {diagnostic} {default}
bool WhiteBoxAPI = false {diagnostic} {default}
uintx WorkStealingHardSpins = 4096 {experimental} {default}
uintx WorkStealingSleepMillis = 1 {experimental} {default}
uintx WorkStealingSpinToYieldRatio = 10 {experimental} {default}
uintx WorkStealingYieldsBeforeSleep = 5000 {experimental} {default}
uintx YoungGenerationSizeIncrement = 20 {product} {default}
uintx YoungGenerationSizeSupplement = 80 {product} {default}
uintx YoungGenerationSizeSupplementDecay = 8 {product} {default}
size_t YoungPLABSize = 4096 {product} {default}
double ZAllocationSpikeTolerance = 2.000000 {experimental} {default}
uint ZCollectionInterval = 0 {experimental} {default}
double ZFragmentationLimit = 25.000000 {experimental} {default}
size_t ZMarkStackSpaceLimit = 8589934592 {experimental} {default}
ccstr ZPath = {experimental} {default}
bool ZProactive = true {diagnostic} {default}
uint ZStatisticsInterval = 10 {diagnostic} {default}
bool ZUncommit = true {experimental} {default}
uintx ZUncommitDelay = 300 {experimental} {default}
bool ZVerifyForwarding = false {diagnostic} {default}
bool ZVerifyMarking = false {diagnostic} {default}
bool ZVerifyObjects = false {diagnostic} {default}
bool ZVerifyRoots = false {diagnostic} {default}
bool ZVerifyViews = false {diagnostic} {default}
bool ZeroTLAB = false {product} {default}
intx hashCode = 5 {experimental} {default}
Оцпии {experimental} для включения требуют флага -XX:+UnlockExperimentalVMOptions. Могут работать, а могут и не работать. Java не гарантирует их корректную работу и их наличие в следующей версии Java.
Оцпии {diagnostic} требуют флага -XX:+UnlockDiagnosticVMOptions. Используются для тестирования, отладки и сбора детальной информации.
Опции {product} стандартные опции. Впрочем, некоторые из них могут работать в комбинации с другими опциями. Например, опции CMSxxx работают, только если вы включили сборщик мусора CMS, а опции {C1 product} и {С2 product} вступают в действие, когда во время работы программы JIT-компилятор переключается с C1 уровня, на уровень C2.
Мои любимые опции
Эти опции я выставляю при старте любого Java-приложения в Production:
-showversion -XX:+PrintCommandLineFlags -XX:+PrintFlagsFinal
Флаг -showversion выводит в консоль сигнатуру версии Java и дальше продолжает выполнение Java-программы. Сигнатура полезна для того, чтобы точно знать какая версия Java и какой её build используется для запуска. Если вы заметите на следующий день, что сигнатура поменялась, значит что-то на Production поменялось без вашего ведома.
Флаг -XX:+PrintCommandLineFlags выводит в консоль параметры, которые вы передаете JVM при запуске. Помогает убедиться, что ваша Java-программа действительно получает те параметры, которые вы пытаетесь передать.
Флаг -XX:+PringFlagsFinal выводит на консоль список всех параметров JVM и их окончательные выставленные значения, которые будут влиять на работу вашего приложения. Если между запусками вы заметите, что какие-то значениея изменились, значит на Production произошло какое-то изменение без вашего ведома.
Разумеется, помимо этих трех простых флагов я использую и другие, например для настройки JVM под low-latency, сборщика мусора, JIT-компилятора, heap и проч., но на эту тему будет отдельная статья.
VM Options Explorer
Замечательный и полезный веб-сайт позволяет посмотреть и удобно отфильтровать все опции JVM по каждой версии Java и разных JVM, например:
Автор веб-сайта — Chris Newland, который является:
- Java Champion 2017 года;
- является соавтором свежей книги Optimizing Java об оптимизации JVM;
- автором JITWatch — утилиты, анализирующей логи JVM JIT-компилятора и выводящая красивые удобные для анализа графики.
Algo & DMA: технологии биржевой торговли 