关键的Java JVM选项和参数 – 信码由缰

2023-04-14 04:33| 来源: 网络整理| 查看: 265

内容纲要 1. 关键的Java JVM选项和参数

让我们来看看在Java环境中可以配置的21个最重要的JVM选项和参数。

-Xms：将设置JVM的初始堆大小。 -Xmx：将设置JVM的最大堆大小。 -Xss：将设置每个线程的内部使用的线程堆栈的大小。 -XX：+UseCompressedOops：启用使用压缩对象指针以减少内存使用的功能。 -XX：+UseThreadPriorities：将指示JVM使用本机线程优先级。 -XX：PermSize：将设置垃圾收集器永久生成空间的初始大小。 -XX：MaxPermSize：将设置垃圾收集器永久生成空间的最大大小。 -XX：NewSize：设置年轻代空间的初始大小。 -XX：MaxNewSize：设置年轻代空间的最大大小。 -XX：SurvivorRatio：设置伊甸园空间与幸存者空间的比例。 -XX：MaxTenuringThreshold：设置幸存者空间中对象的最大年龄。 -XX：+UseParNewGC：指示JVM使用新的并行生成垃圾收集器。 -XX：+UseSerialGC：指示JVM使用串行垃圾收集器。 -XX：+UseG1GC：指示JVM使用Garbage First（G1）垃圾收集器。 -XX：+UseZGC：指示JVM使用ZGC垃圾收集器。 -XX：+HeapDumpOnOutOfMemoryError：告诉JVM在发生OutOfMemoryError时创建堆转储文件。 -XX：HeapDumpPath：为JVM提供自定义路径，在堆转储期间写入堆的内容。 -Djava.library.path：允许您指定在运行时需要的本机库的路径。 -Duser.timezone：允许您为JVM设置自定义时区。 -XX：+PrintGCDetails：指示JVM打印详细的垃圾回收日志，以帮助您进行GC优化。 -XX：+PrintFlagsFinal-version：将打印在JVM上设置的所有当前配置的标志和选项。 2. 如何使用Java JVM选项

所有这些JVM选项都可以通过将它们作为文本附加到Java运行时命令后来简单地使用。

例如，以下命令将使用六个不同的参数运行名为Go的应用程序，以优化内存分配和垃圾回收：

java Go -XX:MaxPermSize=128m -XX:MaxNewSize=256m -Xms768m -Xmx768m -XX:SurvivorRatio=128 -XX:MaxTenuringThreshold=0

Java JVM选项可用于管理内存和优化GC性能

3. 最常用的JVM参数

在列举的所有 JVM 选项中，最常用的是 Xms 和 Xmx，分别设置最小堆大小和最大堆大小。

下面的示例将最小堆大小设置为 768 MB，最大堆大小设置为 2 GB。

-Xms768m -Xmx2048 4. GC 选择 JVM 选项

Java的一个优点是它为开发者执行垃圾回收，这使得应用程序更加健壮，更不容易发生内存泄漏问题。

有许多垃圾回收器可用，具有各种暂停行为和停顿时间。

在启动运行时，您只能使用以下 Java JVM 选项之一选择一个垃圾收集器：

-XX:+UseSerialGC -XX:+UseParallelGC -XX:+USeParNewGC -XX:+UseG1GC -XX:+UseZGC 5. 垃圾回收调优选项

VM实现了一种分代垃圾回收算法，它积极监控新对象，而很少检查旧对象。JVM管理eden空间、tenured空间甚至PermGen空间的方式可以通过JVM选项进行配置，如下：

-XX:MaxPermSize -XX:PermSize -XX:NewSize -XX:MaxNewSize -XX:SurvivorRatio -XX:MaxTenuringThreshold 6. 用于检查的JVM打印选项

JVM还提供了一些打印方法，允许您查看Java运行时的状态。有用的JVM打印选项包括：

-XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+PrintHeapAtGC -XX:+PrintCommandLineFlags -XX:+PrintFlagsFinal

PrintFlagsFinal是一项有趣的JVM选项，它将显示所有JVM标志设置的详细信息，输出内容有超过500行。本文介绍的Java JVM选项已经全部讲解完毕，如果你对PrintFlagsFinal JVM标志的详细输出感兴趣，可以查看上文提到的输出内容。

$ java -XX:+PrintFlagsFinal -version [Global flags] int ActiveProcessorCount = -1 uintx AdaptiveSizeDecrementScaleFactor = 4 uintx AdaptiveSizeMajorGCDecayTimeScale = 10 uintx AdaptiveSizePolicyCollectionCostMargin = 50 uintx AdaptiveSizePolicyInitializingSteps = 20 uintx AdaptiveSizePolicyOutputInterval = 0 uintx AdaptiveSizePolicyWeight = 10 uintx AdaptiveSizeThroughPutPolicy = 0 uintx AdaptiveTimeWeight = 25 bool AggressiveHeap = false intx AliasLevel = 3 bool AlignVector = false ccstr AllocateHeapAt = intx AllocateInstancePrefetchLines = 1 intx AllocatePrefetchDistance = 256 intx AllocatePrefetchInstr = 0 intx AllocatePrefetchLines = 3 intx AllocatePrefetchStepSize = 64 intx AllocatePrefetchStyle = 1 bool AllowParallelDefineClass = false bool AllowRedefinitionToAddDeleteMethods = false bool AllowUserSignalHandlers = false bool AllowVectorizeOnDemand = true bool AlwaysActAsServerClassMachine = false bool AlwaysCompileLoopMethods = false bool AlwaysLockClassLoader = false bool AlwaysPreTouch = false bool AlwaysRestoreFPU = false bool AlwaysTenure = false ccstr ArchiveClassesAtExit = intx ArrayCopyLoadStoreMaxElem = 8 size_t AsyncLogBufferSize = 2097152 intx AutoBoxCacheMax = 128 intx BCEATraceLevel = 0 bool BackgroundCompilation = true size_t BaseFootPrintEstimate = 268435456 intx BiasedLockingBulkRebiasThreshold = 20 intx BiasedLockingBulkRevokeThreshold = 40 intx BiasedLockingDecayTime = 25000 intx BiasedLockingStartupDelay = 0 bool BlockLayoutByFrequency = true intx BlockLayoutMinDiamondPercentage = 20 bool BlockLayoutRotateLoops = true intx C1InlineStackLimit = 5 intx C1MaxInlineLevel = 9 intx C1MaxInlineSize = 35 intx C1MaxRecursiveInlineLevel = 1 intx C1MaxTrivialSize = 6 bool C1OptimizeVirtualCallProfiling = true bool C1ProfileBranches = true bool C1ProfileCalls = true bool C1ProfileCheckcasts = true bool C1ProfileInlinedCalls = true bool C1ProfileVirtualCalls = true bool C1UpdateMethodData = true intx CICompilerCount = 4 bool CICompilerCountPerCPU = true bool CITime = false bool CheckJNICalls = false bool ClassUnloading = true bool ClassUnloadingWithConcurrentMark = true bool ClipInlining = true uintx CodeCacheExpansionSize = 65536 bool CompactStrings = true ccstr CompilationMode = default ccstrlist CompileCommand = ccstr CompileCommandFile = ccstrlist CompileOnly = intx CompileThreshold = 10000 double CompileThresholdScaling = 1.000000 intx CompilerThreadPriority = -1 intx CompilerThreadStackSize = 0 size_t CompressedClassSpaceSize = 1073741824 uint ConcGCThreads = 3 intx ConditionalMoveLimit = 3 intx ContendedPaddingWidth = 128 bool CrashOnOutOfMemoryError = false bool CreateCoredumpOnCrash = true bool CriticalJNINatives = false bool DTraceAllocProbes = false bool DTraceMethodProbes = false bool DTraceMonitorProbes = false bool DisableAttachMechanism = false bool DisableExplicitGC = false bool DisplayVMOutputToStderr = false bool DisplayVMOutputToStdout = false bool DoEscapeAnalysis = true bool DoReserveCopyInSuperWord = true bool DontCompileHugeMethods = true bool DontYieldALot = false ccstr DumpLoadedClassList = bool DumpReplayDataOnError = true bool DumpSharedSpaces = false bool DynamicDumpSharedSpaces = false bool EagerXrunInit = false intx EliminateAllocationArraySizeLimit = 64 bool EliminateAllocations = true bool EliminateAutoBox = true bool EliminateLocks = true bool EliminateNestedLocks = true bool EnableContended = true bool EnableDynamicAgentLoading = true size_t ErgoHeapSizeLimit = 0 ccstr ErrorFile = bool ErrorFileToStderr = false bool ErrorFileToStdout = false uint64_t ErrorLogTimeout = 120 double EscapeAnalysisTimeout = 20.000000 bool EstimateArgEscape = true bool ExecutingUnitTests = false bool ExitOnOutOfMemoryError = false bool ExplicitGCInvokesConcurrent = false bool ExtendedDTraceProbes = false bool ExtensiveErrorReports = false ccstr ExtraSharedClassListFile = bool FilterSpuriousWakeups = true bool FlightRecorder = false ccstr FlightRecorderOptions = bool ForceTimeHighResolution = false intx FreqInlineSize = 325 double G1ConcMarkStepDurationMillis = 10.000000 uintx G1ConcRSHotCardLimit = 4 size_t G1ConcRSLogCacheSize = 10 size_t G1ConcRefinementGreenZone = 0 size_t G1ConcRefinementRedZone = 0 uintx G1ConcRefinementServiceIntervalMillis = 300 uint G1ConcRefinementThreads = 10 size_t G1ConcRefinementThresholdStep = 2 size_t G1ConcRefinementYellowZone = 0 uintx G1ConfidencePercent = 50 size_t G1HeapRegionSize = 2097152 uintx G1HeapWastePercent = 5 uintx G1MixedGCCountTarget = 8 uintx G1PeriodicGCInterval = 0 bool G1PeriodicGCInvokesConcurrent = true double G1PeriodicGCSystemLoadThreshold = 0.000000 intx G1RSetRegionEntries = 512 intx G1RSetSparseRegionEntries = 16 intx G1RSetUpdatingPauseTimePercent = 10 uint G1RefProcDrainInterval = 1000 uintx G1ReservePercent = 10 uintx G1SATBBufferEnqueueingThresholdPercent = 60 size_t G1SATBBufferSize = 1024 size_t G1UpdateBufferSize = 256 bool G1UseAdaptiveConcRefinement = true bool G1UseAdaptiveIHOP = true uintx GCDrainStackTargetSize = 64 uintx GCHeapFreeLimit = 2 uintx GCLockerEdenExpansionPercent = 5 uintx GCPauseIntervalMillis = 201 uintx GCTimeLimit = 98 uintx GCTimeRatio = 12 size_t HeapBaseMinAddress = 2147483648 bool HeapDumpAfterFullGC = false bool HeapDumpBeforeFullGC = false intx HeapDumpGzipLevel = 0 bool HeapDumpOnOutOfMemoryError = false ccstr HeapDumpPath = uintx HeapFirstMaximumCompactionCount = 3 uintx HeapMaximumCompactionInterval = 20 uintx HeapSearchSteps = 3 size_t HeapSizePerGCThread = 43620760 bool IgnoreEmptyClassPaths = false bool IgnoreUnrecognizedVMOptions = false uintx IncreaseFirstTierCompileThresholdAt = 50 bool IncrementalInline = true uintx InitialCodeCacheSize = 2555904 size_t InitialHeapSize = 268435456 uintx InitialRAMFraction = 64 double InitialRAMPercentage = 1.562500 uintx InitialSurvivorRatio = 8 uintx InitialTenuringThreshold = 7 uintx InitiatingHeapOccupancyPercent = 45 bool Inline = true ccstr InlineDataFile = intx InlineSmallCode = 2500 bool InlineSynchronizedMethods = true intx InteriorEntryAlignment = 16 intx InterpreterProfilePercentage = 33 bool JavaMonitorsInStackTrace = true intx JavaPriority10_To_OSPriority = -1 intx JavaPriority1_To_OSPriority = -1 intx JavaPriority2_To_OSPriority = -1 intx JavaPriority3_To_OSPriority = -1 intx JavaPriority4_To_OSPriority = -1 intx JavaPriority5_To_OSPriority = -1 intx JavaPriority6_To_OSPriority = -1 intx JavaPriority7_To_OSPriority = -1 intx JavaPriority8_To_OSPriority = -1 intx JavaPriority9_To_OSPriority = -1 size_t LargePageHeapSizeThreshold = 134217728 size_t LargePageSizeInBytes = 0 intx LiveNodeCountInliningCutoff = 40000 intx LoopMaxUnroll = 16 intx LoopOptsCount = 43 intx LoopPercentProfileLimit = 10 uintx LoopStripMiningIter = 1000 uintx LoopStripMiningIterShortLoop = 100 intx LoopUnrollLimit = 60 intx LoopUnrollMin = 4 bool LoopUnswitching = true bool ManagementServer = false size_t MarkStackSize = 4194304 size_t MarkStackSizeMax = 536870912 uint MarkSweepAlwaysCompactCount = 4 uintx MarkSweepDeadRatio = 5 intx MaxBCEAEstimateLevel = 5 intx MaxBCEAEstimateSize = 150 uint64_t MaxDirectMemorySize = 0 bool MaxFDLimit = true uintx MaxGCMinorPauseMillis = 18446744073709551615 uintx MaxGCPauseMillis = 200 uintx MaxHeapFreeRatio = 70 size_t MaxHeapSize = 4282384384 intx MaxInlineLevel = 15 intx MaxInlineSize = 35 intx MaxJNILocalCapacity = 65536 intx MaxJavaStackTraceDepth = 1024 intx MaxJumpTableSize = 65000 intx MaxJumpTableSparseness = 5 intx MaxLabelRootDepth = 1100 intx MaxLoopPad = 15 size_t MaxMetaspaceExpansion = 5439488 uintx MaxMetaspaceFreeRatio = 70 size_t MaxMetaspaceSize = 18446744073709551615 size_t MaxNewSize = 2569011200 intx MaxNodeLimit = 80000 uint64_t MaxRAM = 137438953472 uintx MaxRAMFraction = 4 double MaxRAMPercentage = 25.000000 intx MaxRecursiveInlineLevel = 1 uintx MaxTenuringThreshold = 15 intx MaxTrivialSize = 6 intx MaxVectorSize = 32 ccstr MetaspaceReclaimPolicy = balanced size_t MetaspaceSize = 22020096 bool MethodFlushing = true size_t MinHeapDeltaBytes = 2097152 uintx MinHeapFreeRatio = 40 size_t MinHeapSize = 8388608 intx MinInliningThreshold = 250 intx MinJumpTableSize = 10 size_t MinMetaspaceExpansion = 327680 uintx MinMetaspaceFreeRatio = 40 uintx MinRAMFraction = 2 double MinRAMPercentage = 50.000000 uintx MinSurvivorRatio = 3 size_t MinTLABSize = 2048 intx MultiArrayExpandLimit = 6 uintx NUMAChunkResizeWeight = 20 size_t NUMAInterleaveGranularity = 2097152 uintx NUMAPageScanRate = 256 size_t NUMASpaceResizeRate = 1073741824 bool NUMAStats = false ccstr NativeMemoryTracking = off bool NeverActAsServerClassMachine = false bool NeverTenure = false uintx NewRatio = 2 size_t NewSize = 1363144 size_t NewSizeThreadIncrease = 5320 intx NmethodSweepActivity = 10 intx NodeLimitFudgeFactor = 2000 uintx NonNMethodCodeHeapSize = 5839372 uintx NonProfiledCodeHeapSize = 122909434 intx NumberOfLoopInstrToAlign = 4 intx ObjectAlignmentInBytes = 8 { size_t OldPLABSize = 1024 size_t OldSize = 5452592 bool OmitStackTraceInFastThrow = true ccstrlist OnError = ccstrlist OnOutOfMemoryError = intx OnStackReplacePercentage = 140 bool OptimizeFill = false bool OptimizePtrCompare = true bool OptimizeStringConcat = true bool OptoBundling = false intx OptoLoopAlignment = 16 bool OptoRegScheduling = true bool OptoScheduling = false uintx PLABWeight = 75 bool PSChunkLargeArrays = true int ParGCArrayScanChunk = 50 uintx ParallelGCBufferWastePct = 10 uint ParallelGCThreads = 10 size_t ParallelOldDeadWoodLimiterMean = 50 size_t ParallelOldDeadWoodLimiterStdDev = 80 bool ParallelRefProcBalancingEnabled = true bool ParallelRefProcEnabled = true bool PartialPeelAtUnsignedTests = true bool PartialPeelLoop = true intx PartialPeelNewPhiDelta = 0 uintx PausePadding = 1 intx PerBytecodeRecompilationCutoff = 200 intx PerBytecodeTrapLimit = 4 intx PerMethodRecompilationCutoff = 400 intx PerMethodTrapLimit = 100 bool PerfAllowAtExitRegistration = false bool PerfBypassFileSystemCheck = false intx PerfDataMemorySize = 32768 intx PerfDataSamplingInterval = 50 ccstr PerfDataSaveFile = bool PerfDataSaveToFile = false bool PerfDisableSharedMem = false intx PerfMaxStringConstLength = 1024 size_t PreTouchParallelChunkSize = 1073741824 bool PreferInterpreterNativeStubs = false intx PrefetchCopyIntervalInBytes = 576 intx PrefetchFieldsAhead = 1 intx PrefetchScanIntervalInBytes = 576 bool PreserveAllAnnotations = false bool PreserveFramePointer = false size_t PretenureSizeThreshold = 0 bool PrintClassHistogram = false bool PrintCodeCache = false bool PrintCodeCacheOnCompilation = false bool PrintCommandLineFlags = false bool PrintCompilation = false bool PrintConcurrentLocks = false bool PrintExtendedThreadInfo = false bool PrintFlagsFinal = true bool PrintFlagsInitial = false bool PrintFlagsRanges = false bool PrintGC = false bool PrintGCDetails = false bool PrintHeapAtSIGBREAK = true bool PrintSharedArchiveAndExit = false bool PrintSharedDictionary = false bool PrintStringTableStatistics = false bool PrintTieredEvents = false bool PrintVMOptions = false bool PrintWarnings = true uintx ProcessDistributionStride = 4 bool ProfileInterpreter = true intx ProfileMaturityPercentage = 20 uintx ProfiledCodeHeapSize = 122909434 uintx PromotedPadding = 3 uintx QueuedAllocationWarningCount = 0 int RTMRetryCount = 5 bool RangeCheckElimination = true bool ReassociateInvariants = true bool RecordDynamicDumpInfo = false bool ReduceBulkZeroing = true bool ReduceFieldZeroing = true bool ReduceInitialCardMarks = true bool ReduceSignalUsage = false intx RefDiscoveryPolicy = 0 bool RegisterFinalizersAtInit = true bool RelaxAccessControlCheck = false ccstr ReplayDataFile = bool RequireSharedSpaces = false uintx ReservedCodeCacheSize = 251658240 bool ResizePLAB = true bool ResizeTLAB = true bool RestoreMXCSROnJNICalls = false bool RestrictContended = true bool RestrictReservedStack = true bool RewriteBytecodes = true bool RewriteFrequentPairs = true bool SafepointTimeout = false intx SafepointTimeoutDelay = 10000 bool ScavengeBeforeFullGC = false bool SegmentedCodeCache = true intx SelfDestructTimer = 0 ccstr SharedArchiveConfigFile = ccstr SharedArchiveFile = size_t SharedBaseAddress = 34359738368 ccstr SharedClassListFile = uintx SharedSymbolTableBucketSize = 4 ccstr ShenandoahGCHeuristics = adaptive ccstr ShenandoahGCMode = satb bool ShowCodeDetailsInExceptionMessages = true bool ShowMessageBoxOnError = false bool ShrinkHeapInSteps = true size_t SoftMaxHeapSize = 4282384384 intx SoftRefLRUPolicyMSPerMB = 1000 bool SplitIfBlocks = true intx StackRedPages = 1 intx StackReservedPages = 0 intx StackShadowPages = 7 bool StackTraceInThrowable = true intx StackYellowPages = 3 uintx StartAggressiveSweepingAt = 10 bool StartAttachListener = false ccstr StartFlightRecording = uint StringDeduplicationAgeThreshold = 3 uintx StringTableSize = 65536 bool SuperWordLoopUnrollAnalysis = true bool SuperWordReductions = true bool SuppressFatalErrorMessage = false uintx SurvivorPadding = 3 uintx SurvivorRatio = 8 double SweeperThreshold = 0.500000 uintx TLABAllocationWeight = 35 uintx TLABRefillWasteFraction = 64 size_t TLABSize = 0 bool TLABStats = true uintx TLABWasteIncrement = 4 uintx TLABWasteTargetPercent = 1 uintx TargetPLABWastePct = 10 uintx TargetSurvivorRatio = 50 uintx TenuredGenerationSizeIncrement = 20 uintx TenuredGenerationSizeSupplement = 80 uintx TenuredGenerationSizeSupplementDecay = 2 intx ThreadPriorityPolicy = 0 bool ThreadPriorityVerbose = false intx ThreadStackSize = 0 uintx ThresholdTolerance = 10 intx Tier0BackedgeNotifyFreqLog = 10 intx Tier0InvokeNotifyFreqLog = 7 intx Tier0ProfilingStartPercentage = 200 intx Tier23InlineeNotifyFreqLog = 20 intx Tier2BackEdgeThreshold = 0 intx Tier2BackedgeNotifyFreqLog = 14 intx Tier2CompileThreshold = 0 intx Tier2InvokeNotifyFreqLog = 11 intx Tier3BackEdgeThreshold = 60000 intx Tier3BackedgeNotifyFreqLog = 13 intx Tier3CompileThreshold = 2000 intx Tier3DelayOff = 2 intx Tier3DelayOn = 5 intx Tier3InvocationThreshold = 200 intx Tier3InvokeNotifyFreqLog = 10 intx Tier3LoadFeedback = 5 intx Tier3MinInvocationThreshold = 100 intx Tier4BackEdgeThreshold = 40000 intx Tier4CompileThreshold = 15000 intx Tier4InvocationThreshold = 5000 intx Tier4LoadFeedback = 3 intx Tier4MinInvocationThreshold = 600 bool TieredCompilation = true intx TieredCompileTaskTimeout = 50 intx TieredRateUpdateMaxTime = 25 intx TieredRateUpdateMinTime = 1 intx TieredStopAtLevel = 4 bool TimeLinearScan = false ccstr TraceJVMTI = intx TrackedInitializationLimit = 50 bool TrapBasedNullChecks = false bool TrapBasedRangeChecks = false intx TypeProfileArgsLimit = 2 uintx TypeProfileLevel = 111 intx TypeProfileMajorReceiverPercent = 90 intx TypeProfileParmsLimit = 2 intx TypeProfileWidth = 2 intx UnguardOnExecutionViolation = 0 bool UseAES = true intx UseAVX = 2 bool UseAdaptiveGenerationSizePolicyAtMajorCollection = true bool UseAdaptiveGenerationSizePolicyAtMinorCollection = true bool UseAdaptiveNUMAChunkSizing = true bool UseAdaptiveSizeDecayMajorGCCost = true bool UseAdaptiveSizePolicy = true bool UseAdaptiveSizePolicyFootprintGoal = true bool UseAdaptiveSizePolicyWithSystemGC = false bool UseAddressNop = true bool UseBASE64Intrinsics = false bool UseBMI1Instructions = true bool UseBMI2Instructions = true bool UseBiasedLocking = false bool UseBimorphicInlining = true bool UseCLMUL = true bool UseCMoveUnconditionally = false bool UseCodeAging = true bool UseCodeCacheFlushing = true bool UseCompiler = true bool UseCompressedClassPointers = true { bool UseCompressedOops = true { bool UseCondCardMark = false bool UseCountLeadingZerosInstruction = true bool UseCountTrailingZerosInstruction = true bool UseCountedLoopSafepoints = true bool UseCounterDecay = true bool UseDivMod = true bool UseDynamicNumberOfCompilerThreads = true bool UseDynamicNumberOfGCThreads = true bool UseEmptySlotsInSupers = true bool UseFMA = true bool UseFPUForSpilling = true bool UseFastJNIAccessors = true bool UseFastStosb = false bool UseG1GC = true bool UseGCOverheadLimit = true bool UseHeavyMonitors = false bool UseInlineCaches = true bool UseInterpreter = true bool UseJumpTables = true bool UseLargePages = false bool UseLargePagesIndividualAllocation = false bool UseLoopCounter = true bool UseLoopInvariantCodeMotion = true bool UseLoopPredicate = true bool UseMaximumCompactionOnSystemGC = true bool UseNUMA = false bool UseNUMAInterleaving = false bool UseNewLongLShift = true bool UseNotificationThread = true bool UseOSErrorReporting = false bool UseOnStackReplacement = true bool UseOnlyInlinedBimorphic = true bool UseOptoBiasInlining = false bool UsePSAdaptiveSurvivorSizePolicy = true bool UseParallelGC = false bool UsePerfData = true bool UsePopCountInstruction = true bool UseProfiledLoopPredicate = true bool UseRTMDeopt = false bool UseRTMLocking = false bool UseSHA = true intx UseSSE = 4 bool UseSSE42Intrinsics = true bool UseSerialGC = false bool UseSharedSpaces = true bool UseShenandoahGC = false bool UseSignalChaining = true bool UseStoreImmI16 = true bool UseStringDeduplication = false bool UseSubwordForMaxVector = true bool UseSuperWord = true bool UseTLAB = true bool UseThreadPriorities = true bool UseTypeProfile = true bool UseTypeSpeculation = true bool UseUnalignedLoadStores = true bool UseVectorCmov = false bool UseXMMForArrayCopy = true bool UseXMMForObjInit = true bool UseXmmI2D = true bool UseXmmI2F = true bool UseXmmLoadAndClearUpper = true bool UseXmmRegToRegMoveAll = true bool UseZGC = false intx VMThreadPriority = -1 intx VMThreadStackSize = 0 intx ValueMapInitialSize = 11 intx ValueMapMaxLoopSize = 8 intx ValueSearchLimit = 1000 bool VerifySharedSpaces = false uintx YoungGenerationSizeIncrement = 20 uintx YoungGenerationSizeSupplement = 80 uintx YoungGenerationSizeSupplementDecay = 8 size_t YoungPLABSize = 4096 double ZAllocationSpikeTolerance = 2.000000 double ZCollectionInterval = 0.000000 double ZFragmentationLimit = 25.000000 size_t ZMarkStackSpaceLimit = 8589934592 bool ZProactive = true bool ZUncommit = true uintx ZUncommitDelay = 300 bool ZeroTLAB = false openjdk version "17.0.6" 2023-01-17 OpenJDK Runtime Environment Temurin-17.0.6+10 (build 17.0.6+10) OpenJDK 64-Bit Server VM Temurin-17.0.6+10 (build 17.0.6+10, mixed mode, sharing)

【本文地址】

公司简介

联系我们