| /* |
| * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #ifndef SHARE_GC_SHARED_GC_GLOBALS_HPP |
| #define SHARE_GC_SHARED_GC_GLOBALS_HPP |
| |
| #include "runtime/globals_shared.hpp" |
| #include "utilities/macros.hpp" |
| #if INCLUDE_EPSILONGC |
| #include "gc/epsilon/epsilon_globals.hpp" |
| #endif |
| #if INCLUDE_G1GC |
| #include "gc/g1/g1_globals.hpp" |
| #endif |
| #if INCLUDE_PARALLELGC |
| #include "gc/parallel/parallel_globals.hpp" |
| #endif |
| #if INCLUDE_SERIALGC |
| #include "gc/serial/serial_globals.hpp" |
| #endif |
| #if INCLUDE_SHENANDOAHGC |
| #include "gc/shenandoah/shenandoah_globals.hpp" |
| #endif |
| #if INCLUDE_ZGC |
| #include "gc/z/z_globals.hpp" |
| #endif |
| |
| #define GC_FLAGS(develop, \ |
| develop_pd, \ |
| product, \ |
| product_pd, \ |
| range, \ |
| constraint) \ |
| \ |
| EPSILONGC_ONLY(GC_EPSILON_FLAGS( \ |
| develop, \ |
| develop_pd, \ |
| product, \ |
| product_pd, \ |
| range, \ |
| constraint)) \ |
| \ |
| G1GC_ONLY(GC_G1_FLAGS( \ |
| develop, \ |
| develop_pd, \ |
| product, \ |
| product_pd, \ |
| range, \ |
| constraint)) \ |
| \ |
| PARALLELGC_ONLY(GC_PARALLEL_FLAGS( \ |
| develop, \ |
| develop_pd, \ |
| product, \ |
| product_pd, \ |
| range, \ |
| constraint)) \ |
| \ |
| SERIALGC_ONLY(GC_SERIAL_FLAGS( \ |
| develop, \ |
| develop_pd, \ |
| product, \ |
| product_pd, \ |
| range, \ |
| constraint)) \ |
| \ |
| SHENANDOAHGC_ONLY(GC_SHENANDOAH_FLAGS( \ |
| develop, \ |
| develop_pd, \ |
| product, \ |
| product_pd, \ |
| range, \ |
| constraint)) \ |
| \ |
| ZGC_ONLY(GC_Z_FLAGS( \ |
| develop, \ |
| develop_pd, \ |
| product, \ |
| product_pd, \ |
| range, \ |
| constraint)) \ |
| \ |
| /* gc */ \ |
| \ |
| product(bool, UseSerialGC, false, \ |
| "Use the Serial garbage collector") \ |
| \ |
| product(bool, UseG1GC, false, \ |
| "Use the Garbage-First garbage collector") \ |
| \ |
| product(bool, UseParallelGC, false, \ |
| "Use the Parallel garbage collector.") \ |
| \ |
| product(bool, UseEpsilonGC, false, EXPERIMENTAL, \ |
| "Use the Epsilon (no-op) garbage collector") \ |
| \ |
| product(bool, UseZGC, false, \ |
| "Use the Z garbage collector") \ |
| \ |
| product(bool, UseShenandoahGC, false, \ |
| "Use the Shenandoah garbage collector") \ |
| \ |
| /* notice: the max range value here is INT_MAX not UINT_MAX */ \ |
| /* to protect from overflows */ \ |
| product(uint, ParallelGCThreads, 0, \ |
| "Number of parallel threads parallel gc will use") \ |
| range(0, INT_MAX) \ |
| \ |
| product(bool, UseDynamicNumberOfGCThreads, true, \ |
| "Dynamically choose the number of threads up to a maximum of " \ |
| "ParallelGCThreads parallel collectors will use for garbage " \ |
| "collection work") \ |
| \ |
| product(bool, InjectGCWorkerCreationFailure, false, DIAGNOSTIC, \ |
| "Inject thread creation failures for " \ |
| "UseDynamicNumberOfGCThreads") \ |
| \ |
| product(size_t, HeapSizePerGCThread, ScaleForWordSize(32*M), \ |
| "Size of heap (bytes) per GC thread used in calculating the " \ |
| "number of GC threads") \ |
| constraint(VMPageSizeConstraintFunc, AtParse) \ |
| \ |
| product(uint, ConcGCThreads, 0, \ |
| "Number of threads concurrent gc will use") \ |
| \ |
| product(bool, AlwaysTenure, false, \ |
| "Always tenure objects in eden (ParallelGC only)") \ |
| \ |
| product(bool, NeverTenure, false, \ |
| "Never tenure objects in eden, may tenure on overflow " \ |
| "(ParallelGC only)") \ |
| \ |
| product(bool, ExplicitGCInvokesConcurrent, false, \ |
| "A System.gc() request invokes a concurrent collection; " \ |
| "(effective only when using concurrent collectors)") \ |
| \ |
| product(uint, ParallelGCBufferWastePct, 10, \ |
| "Wasted fraction of parallel allocation buffer") \ |
| range(0, 100) \ |
| \ |
| product(uint, TargetPLABWastePct, 10, \ |
| "Target wasted space in last buffer as percent of overall " \ |
| "allocation") \ |
| range(1, 100) \ |
| \ |
| product(uint, PLABWeight, 75, \ |
| "Percentage (0-100) used to weight the current sample when " \ |
| "computing exponentially decaying average for ResizePLAB") \ |
| range(0, 100) \ |
| \ |
| product(bool, ResizePLAB, true, \ |
| "Dynamically resize (survivor space) promotion LAB's") \ |
| \ |
| product(int, ParGCArrayScanChunk, 50, \ |
| "Scan a subset of object array and push remainder, if array is " \ |
| "bigger than this") \ |
| range(1, INT_MAX/3) \ |
| \ |
| \ |
| product(bool, AlwaysPreTouch, false, \ |
| "Force all freshly committed pages to be pre-touched") \ |
| \ |
| product(bool, AlwaysPreTouchStacks, false, DIAGNOSTIC, \ |
| "Force java thread stacks to be fully pre-touched") \ |
| \ |
| product_pd(size_t, PreTouchParallelChunkSize, \ |
| "Per-thread chunk size for parallel memory pre-touch.") \ |
| range(4*K, SIZE_MAX / 2) \ |
| \ |
| /* where does the range max value of (max_jint - 1) come from? */ \ |
| product(size_t, MarkStackSizeMax, NOT_LP64(4*M) LP64_ONLY(512*M), \ |
| "Maximum size of marking stack in bytes.") \ |
| range(1, (INT_MAX - 1)) \ |
| \ |
| product(size_t, MarkStackSize, NOT_LP64(64*K) LP64_ONLY(4*M), \ |
| "Size of marking stack in bytes.") \ |
| constraint(MarkStackSizeConstraintFunc,AfterErgo) \ |
| range(1, (INT_MAX - 1)) \ |
| \ |
| product(bool, ParallelRefProcEnabled, false, \ |
| "Enable parallel reference processing whenever possible") \ |
| \ |
| product(bool, ParallelRefProcBalancingEnabled, true, \ |
| "Enable balancing of reference processing queues") \ |
| \ |
| product(size_t, ReferencesPerThread, 1000, EXPERIMENTAL, \ |
| "Ergonomically start one thread for this amount of " \ |
| "references for reference processing if " \ |
| "ParallelRefProcEnabled is true. Specify 0 to disable and " \ |
| "use all threads.") \ |
| \ |
| product(uint, InitiatingHeapOccupancyPercent, 45, \ |
| "The percent occupancy (IHOP) of the current old generation " \ |
| "capacity above which a concurrent mark cycle will be initiated " \ |
| "Its value may change over time if adaptive IHOP is enabled, " \ |
| "otherwise the value remains constant. " \ |
| "In the latter case a value of 0 will result as frequent as " \ |
| "possible concurrent marking cycles. A value of 100 disables " \ |
| "concurrent marking. " \ |
| "Fragmentation waste in the old generation is not considered " \ |
| "free space in this calculation. (G1 collector only)") \ |
| range(0, 100) \ |
| \ |
| develop(bool, ScavengeALot, false, \ |
| "Force scavenge at every Nth exit from the runtime system " \ |
| "(N=ScavengeALotInterval)") \ |
| \ |
| develop(bool, FullGCALot, false, \ |
| "Force full gc at every Nth exit from the runtime system " \ |
| "(N=FullGCALotInterval)") \ |
| \ |
| develop(bool, GCALotAtAllSafepoints, false, \ |
| "Enforce ScavengeALot/GCALot at all potential safepoints") \ |
| \ |
| develop(bool, PromotionFailureALot, false, \ |
| "Use promotion failure handling on every youngest generation " \ |
| "collection") \ |
| \ |
| develop(uintx, PromotionFailureALotCount, 1000, \ |
| "Number of promotion failures occurring at PLAB promotion " \ |
| "attempts at young collectors") \ |
| \ |
| develop(uintx, PromotionFailureALotInterval, 5, \ |
| "Total collections between promotion failures a lot") \ |
| \ |
| product(uintx, WorkStealingSleepMillis, 1, EXPERIMENTAL, \ |
| "Sleep time when sleep is used for yields") \ |
| \ |
| product(uintx, WorkStealingYieldsBeforeSleep, 5000, EXPERIMENTAL, \ |
| "Number of yields before a sleep is done during work stealing") \ |
| \ |
| product(uintx, WorkStealingHardSpins, 4096, EXPERIMENTAL, \ |
| "Number of iterations in a spin loop between checks on " \ |
| "time out of hard spin") \ |
| \ |
| product(uintx, WorkStealingSpinToYieldRatio, 10, EXPERIMENTAL, \ |
| "Ratio of hard spins to calls to yield") \ |
| \ |
| develop(uintx, ObjArrayMarkingStride, 2048, \ |
| "Number of object array elements to push onto the marking stack " \ |
| "before pushing a continuation entry") \ |
| \ |
| product_pd(bool, NeverActAsServerClassMachine, \ |
| "Never act like a server-class machine") \ |
| \ |
| product(bool, AlwaysActAsServerClassMachine, false, \ |
| "Always act like a server-class machine") \ |
| \ |
| product_pd(uint64_t, MaxRAM, \ |
| "Real memory size (in bytes) used to set maximum heap size") \ |
| range(0, 0XFFFFFFFFFFFFFFFF) \ |
| \ |
| product(bool, AggressiveHeap, false, \ |
| "Optimize heap options for long-running memory intensive apps") \ |
| \ |
| product(size_t, ErgoHeapSizeLimit, 0, \ |
| "Maximum ergonomically set heap size (in bytes); zero means use " \ |
| "MaxRAM * MaxRAMPercentage / 100") \ |
| range(0, max_uintx) \ |
| \ |
| product(double, MaxRAMPercentage, 25.0, \ |
| "Maximum percentage of real memory used for maximum heap size") \ |
| range(0.0, 100.0) \ |
| \ |
| product(double, MinRAMPercentage, 50.0, \ |
| "Minimum percentage of real memory used for maximum heap" \ |
| "size on systems with small physical memory size") \ |
| range(0.0, 100.0) \ |
| \ |
| product(double, InitialRAMPercentage, 1.5625, \ |
| "Percentage of real memory used for initial heap size") \ |
| range(0.0, 100.0) \ |
| \ |
| product(int, ActiveProcessorCount, -1, \ |
| "Specify the CPU count the VM should use and report as active") \ |
| \ |
| develop(uintx, MaxVirtMemFraction, 2, \ |
| "Maximum fraction (1/n) of virtual memory used for ergonomically "\ |
| "determining maximum heap size") \ |
| range(1, max_uintx) \ |
| \ |
| product(bool, UseAdaptiveSizePolicy, true, \ |
| "Use adaptive generation sizing policies") \ |
| \ |
| product(bool, UsePSAdaptiveSurvivorSizePolicy, true, \ |
| "Use adaptive survivor sizing policies") \ |
| \ |
| product(bool, UseAdaptiveGenerationSizePolicyAtMinorCollection, true, \ |
| "Use adaptive young-old sizing policies at minor collections") \ |
| \ |
| product(bool, UseAdaptiveGenerationSizePolicyAtMajorCollection, true, \ |
| "Use adaptive young-old sizing policies at major collections") \ |
| \ |
| product(bool, UseAdaptiveSizePolicyWithSystemGC, false, \ |
| "Include statistics from System.gc() for adaptive size policy") \ |
| \ |
| product(uint, AdaptiveSizeThroughPutPolicy, 0, \ |
| "Policy for changing generation size for throughput goals") \ |
| range(0, 1) \ |
| \ |
| product(uintx, AdaptiveSizePolicyInitializingSteps, 20, \ |
| "Number of steps where heuristics is used before data is used") \ |
| range(0, max_uintx) \ |
| \ |
| develop(uintx, AdaptiveSizePolicyReadyThreshold, 5, \ |
| "Number of collections before the adaptive sizing is started") \ |
| \ |
| product(uintx, AdaptiveSizePolicyOutputInterval, 0, \ |
| "Collection interval for printing information; zero means never") \ |
| range(0, max_uintx) \ |
| \ |
| product(bool, UseAdaptiveSizePolicyFootprintGoal, true, \ |
| "Use adaptive minimum footprint as a goal") \ |
| \ |
| product(uint, AdaptiveSizePolicyWeight, 10, \ |
| "Weight given to exponential resizing, between 0 and 100") \ |
| range(0, 100) \ |
| \ |
| product(uint, AdaptiveTimeWeight, 25, \ |
| "Weight given to time in adaptive policy, between 0 and 100") \ |
| range(0, 100) \ |
| \ |
| product(uint, PausePadding, 1, \ |
| "How much buffer to keep for pause time") \ |
| range(0, UINT_MAX) \ |
| \ |
| product(uint, PromotedPadding, 3, \ |
| "How much buffer to keep for promotion failure") \ |
| range(0, UINT_MAX) \ |
| \ |
| product(uint, SurvivorPadding, 3, \ |
| "How much buffer to keep for survivor overflow") \ |
| range(0, UINT_MAX) \ |
| \ |
| product(uint, ThresholdTolerance, 10, \ |
| "Allowed collection cost difference between generations") \ |
| range(0, 100) \ |
| \ |
| product(uint, YoungGenerationSizeIncrement, 20, \ |
| "Adaptive size percentage change in young generation") \ |
| range(0, 100) \ |
| \ |
| product(uint, YoungGenerationSizeSupplement, 80, \ |
| "Supplement to YoungGenerationSizeIncrement used at startup") \ |
| range(0, 100) \ |
| \ |
| product(uintx, YoungGenerationSizeSupplementDecay, 8, \ |
| "Decay factor to YoungGenerationSizeSupplement") \ |
| range(1, max_uintx) \ |
| \ |
| product(uint, TenuredGenerationSizeIncrement, 20, \ |
| "Adaptive size percentage change in tenured generation") \ |
| range(0, 100) \ |
| \ |
| product(uint, TenuredGenerationSizeSupplement, 80, \ |
| "Supplement to TenuredGenerationSizeIncrement used at startup") \ |
| range(0, 100) \ |
| \ |
| product(uintx, TenuredGenerationSizeSupplementDecay, 2, \ |
| "Decay factor to TenuredGenerationSizeIncrement") \ |
| range(1, max_uintx) \ |
| \ |
| product(uintx, MaxGCPauseMillis, max_uintx - 1, \ |
| "Adaptive size policy maximum GC pause time goal in millisecond, "\ |
| "or (G1 Only) the maximum GC time per MMU time slice") \ |
| range(1, max_uintx - 1) \ |
| constraint(MaxGCPauseMillisConstraintFunc,AfterErgo) \ |
| \ |
| product(uintx, GCPauseIntervalMillis, 0, \ |
| "Time slice for MMU specification") \ |
| constraint(GCPauseIntervalMillisConstraintFunc,AfterErgo) \ |
| \ |
| product(uint, GCTimeRatio, 99, \ |
| "Adaptive size policy application time to GC time ratio") \ |
| range(0, UINT_MAX) \ |
| \ |
| product(uintx, AdaptiveSizeDecrementScaleFactor, 4, \ |
| "Adaptive size scale down factor for shrinking") \ |
| range(1, max_uintx) \ |
| \ |
| product(bool, UseAdaptiveSizeDecayMajorGCCost, true, \ |
| "Adaptive size decays the major cost for long major intervals") \ |
| \ |
| product(uintx, AdaptiveSizeMajorGCDecayTimeScale, 10, \ |
| "Time scale over which major costs decay") \ |
| range(0, max_uintx) \ |
| \ |
| product(uintx, MinSurvivorRatio, 3, \ |
| "Minimum ratio of young generation/survivor space size") \ |
| range(3, max_uintx) \ |
| \ |
| product(uintx, InitialSurvivorRatio, 8, \ |
| "Initial ratio of young generation/survivor space size") \ |
| range(3, max_uintx) \ |
| \ |
| product(bool, UseGCOverheadLimit, true, \ |
| "Use policy to limit of proportion of time spent in GC " \ |
| "before an OutOfMemory error is thrown") \ |
| \ |
| product(uint, GCTimeLimit, 98, \ |
| "Limit of the proportion of time spent in GC before " \ |
| "an OutOfMemoryError is thrown (used with GCHeapFreeLimit)") \ |
| range(0, 100) \ |
| \ |
| product(uint, GCHeapFreeLimit, 2, \ |
| "Minimum percentage of free space after a full GC before an " \ |
| "OutOfMemoryError is thrown (used with GCTimeLimit)") \ |
| range(0, 100) \ |
| \ |
| develop(uintx, GCOverheadLimitThreshold, 5, \ |
| "Number of consecutive collections before gc time limit fires") \ |
| range(1, max_uintx) \ |
| \ |
| product(intx, PrefetchCopyIntervalInBytes, -1, \ |
| "How far ahead to prefetch destination area (<= 0 means off)") \ |
| range(-1, max_jint) \ |
| \ |
| product(intx, PrefetchScanIntervalInBytes, -1, \ |
| "How far ahead to prefetch scan area (<= 0 means off)") \ |
| range(-1, max_jint) \ |
| \ |
| product(bool, VerifyDuringStartup, false, DIAGNOSTIC, \ |
| "Verify memory system before executing any Java code " \ |
| "during VM initialization") \ |
| \ |
| product(bool, VerifyBeforeExit, trueInDebug, DIAGNOSTIC, \ |
| "Verify system before exiting") \ |
| \ |
| product(bool, VerifyBeforeGC, false, DIAGNOSTIC, \ |
| "Verify memory system before GC") \ |
| \ |
| product(bool, VerifyAfterGC, false, DIAGNOSTIC, \ |
| "Verify memory system after GC") \ |
| \ |
| product(bool, VerifyDuringGC, false, DIAGNOSTIC, \ |
| "Verify memory system during GC (between phases)") \ |
| \ |
| product(int, VerifyArchivedFields, 0, DIAGNOSTIC, \ |
| "Verify memory when archived oop fields are loaded from CDS; " \ |
| "0: No check; " \ |
| "1: Basic verification with VM_Verify (no side effects); " \ |
| "2: Detailed verification by forcing a GC (with side effects)") \ |
| range(0, 2) \ |
| \ |
| product(ccstrlist, VerifyGCType, "", DIAGNOSTIC, \ |
| "GC type(s) to verify when Verify*GC is enabled." \ |
| "Available types are collector specific.") \ |
| \ |
| product(ccstrlist, VerifySubSet, "", DIAGNOSTIC, \ |
| "Memory sub-systems to verify when Verify*GC flag(s) " \ |
| "are enabled. One or more sub-systems can be specified " \ |
| "in a comma separated string. Sub-systems are: " \ |
| "threads, heap, symbol_table, string_table, codecache, " \ |
| "dictionary, classloader_data_graph, metaspace, jni_handles, " \ |
| "codecache_oops, resolved_method_table, stringdedup") \ |
| \ |
| product(bool, DeferInitialCardMark, false, DIAGNOSTIC, \ |
| "When +ReduceInitialCardMarks, explicitly defer any that " \ |
| "may arise from new_pre_store_barrier") \ |
| \ |
| product(bool, UseCondCardMark, false, \ |
| "Check for already marked card before updating card table") \ |
| \ |
| product(bool, DisableExplicitGC, false, \ |
| "Ignore calls to System.gc()") \ |
| \ |
| product(bool, PrintGC, false, \ |
| "Print message at garbage collection. " \ |
| "Deprecated, use -Xlog:gc instead.") \ |
| \ |
| product(bool, PrintGCDetails, false, \ |
| "Print more details at garbage collection. " \ |
| "Deprecated, use -Xlog:gc* instead.") \ |
| \ |
| develop(intx, ConcGCYieldTimeout, 0, \ |
| "If non-zero, assert that GC threads yield within this " \ |
| "number of milliseconds") \ |
| range(0, max_intx) \ |
| \ |
| develop(int, ScavengeALotInterval, 1, \ |
| "Interval between which scavenge will occur with +ScavengeALot") \ |
| \ |
| develop(int, FullGCALotInterval, 1, \ |
| "Interval between which full gc will occur with +FullGCALot") \ |
| \ |
| develop(int, FullGCALotStart, 0, \ |
| "For which invocation to start FullGCAlot") \ |
| \ |
| develop(int, FullGCALotDummies, 32*K, \ |
| "Dummy object allocated with +FullGCALot, forcing all objects " \ |
| "to move") \ |
| \ |
| /* gc parameters */ \ |
| product(size_t, MinHeapSize, 0, \ |
| "Minimum heap size (in bytes); zero means use ergonomics") \ |
| constraint(MinHeapSizeConstraintFunc,AfterErgo) \ |
| \ |
| product(size_t, InitialHeapSize, 0, \ |
| "Initial heap size (in bytes); zero means use ergonomics") \ |
| constraint(InitialHeapSizeConstraintFunc,AfterErgo) \ |
| \ |
| product(size_t, MaxHeapSize, ScaleForWordSize(96*M), \ |
| "Maximum heap size (in bytes)") \ |
| constraint(MaxHeapSizeConstraintFunc,AfterErgo) \ |
| \ |
| product(size_t, SoftMaxHeapSize, 0, MANAGEABLE, \ |
| "Soft limit for maximum heap size (in bytes)") \ |
| constraint(SoftMaxHeapSizeConstraintFunc,AfterMemoryInit) \ |
| \ |
| product(size_t, NewSize, ScaleForWordSize(1*M), \ |
| "Initial new generation size (in bytes)") \ |
| constraint(NewSizeConstraintFunc,AfterErgo) \ |
| \ |
| product(size_t, MaxNewSize, max_uintx, \ |
| "Maximum new generation size (in bytes), max_uintx means set " \ |
| "ergonomically") \ |
| range(0, max_uintx) \ |
| \ |
| product_pd(size_t, HeapBaseMinAddress, \ |
| "OS specific low limit for heap base address") \ |
| constraint(HeapBaseMinAddressConstraintFunc,AfterErgo) \ |
| \ |
| product(size_t, PretenureSizeThreshold, 0, \ |
| "Maximum size in bytes of objects allocated in DefNew " \ |
| "generation; zero means no maximum") \ |
| range(0, max_uintx) \ |
| \ |
| product(uintx, SurvivorRatio, 8, \ |
| "Ratio of eden/survivor space size") \ |
| range(1, max_uintx-2) \ |
| constraint(SurvivorRatioConstraintFunc,AfterMemoryInit) \ |
| \ |
| product(uintx, NewRatio, 2, \ |
| "Ratio of old/new generation sizes") \ |
| range(0, max_uintx-1) \ |
| \ |
| product_pd(size_t, NewSizeThreadIncrease, \ |
| "Additional size added to desired new generation size per " \ |
| "non-daemon thread (in bytes)") \ |
| range(0, max_uintx) \ |
| \ |
| product(uintx, QueuedAllocationWarningCount, 0, \ |
| "Number of times an allocation that queues behind a GC " \ |
| "will retry before printing a warning") \ |
| range(0, max_uintx) \ |
| \ |
| product(uintx, VerifyGCStartAt, 0, DIAGNOSTIC, \ |
| "GC invoke count where +VerifyBefore/AfterGC kicks in") \ |
| range(0, max_uintx) \ |
| \ |
| product(uint, MaxTenuringThreshold, 15, \ |
| "Maximum value for tenuring threshold") \ |
| range(0, markWord::max_age + 1) \ |
| constraint(MaxTenuringThresholdConstraintFunc,AfterErgo) \ |
| \ |
| product(uint, InitialTenuringThreshold, 7, \ |
| "Initial value for tenuring threshold") \ |
| range(0, markWord::max_age + 1) \ |
| constraint(InitialTenuringThresholdConstraintFunc,AfterErgo) \ |
| \ |
| product(uint, TargetSurvivorRatio, 50, \ |
| "Desired percentage of survivor space used after scavenge") \ |
| range(0, 100) \ |
| \ |
| product(uint, MarkSweepDeadRatio, 5, \ |
| "Percentage (0-100) of the old gen allowed as dead wood. " \ |
| "Serial full gc treats this as both the minimum and maximum " \ |
| "value. " \ |
| "Parallel full gc treats this as maximum value, i.e. when " \ |
| "allowing dead wood, Parallel full gc wastes at most this amount "\ |
| "of space." \ |
| "G1 full gc treats this as an allowed garbage threshold to skip " \ |
| "compaction of heap regions, i.e. if a heap region has less " \ |
| "garbage than this value, then the region will not be compacted" \ |
| "during G1 full GC.") \ |
| range(0, 100) \ |
| \ |
| product(uint, MarkSweepAlwaysCompactCount, 4, \ |
| "How often should we fully compact the heap (ignoring the dead " \ |
| "space parameters)") \ |
| range(1, UINT_MAX) \ |
| \ |
| develop(uintx, GCExpandToAllocateDelayMillis, 0, \ |
| "Delay between expansion and allocation (in milliseconds)") \ |
| \ |
| product(uint, GCDrainStackTargetSize, 64, \ |
| "Number of entries we will try to leave on the stack " \ |
| "during parallel gc") \ |
| range(0, 8 * 1024) \ |
| \ |
| product(uint, GCCardSizeInBytes, 512, \ |
| "Card table entry size (in bytes) for card based collectors") \ |
| range(128, NOT_LP64(512) LP64_ONLY(1024)) \ |
| constraint(GCCardSizeInBytesConstraintFunc,AtParse) |
| // end of GC_FLAGS |
| |
| DECLARE_FLAGS(GC_FLAGS) |
| |
| #endif // SHARE_GC_SHARED_GC_GLOBALS_HPP |
