/* * Copyright (c) 2001, 2024, 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_G1_G1_GLOBALS_HPP #define SHARE_GC_G1_G1_GLOBALS_HPP #include "runtime/globals_shared.hpp" // Enable allocation failure injector by default in non-product builds. #ifdef ALLOCATION_FAILURE_INJECTOR #error "ALLOCATION_FAILURE_INJECTOR already defined" #endif #ifndef PRODUCT #define ALLOCATION_FAILURE_INJECTOR 1 #else #define ALLOCATION_FAILURE_INJECTOR 0 #endif #if ALLOCATION_FAILURE_INJECTOR #define GC_G1_EVACUATION_FAILURE_FLAGS(develop, \ develop_pd, \ product, \ product_pd, \ range, \ constraint) \ \ product(bool, G1GCAllocationFailureALot, false, \ "Force execution of evacuation failure handling by inducing " \ "allocation failures during certain young collection pauses") \ \ product(uintx, G1GCAllocationFailureALotCount, 1000, \ "Number of successful evacuations between induced allocation " \ "failures occurring at object copying per thread") \ \ product(uintx, G1GCAllocationFailureALotInterval, 5, \ "Total collections between forced triggering of evacuation " \ "failures") \ \ product(bool, G1GCAllocationFailureALotDuringConcMark, true, \ "Trigger evacuation failure handling in collection pauses where " \ "marking is in progress") \ \ product(bool, G1GCAllocationFailureALotDuringConcurrentStart, true, \ "Trigger evacuation failure handling during concurrent start " \ "collection pauses") \ \ product(bool, G1GCAllocationFailureALotDuringYoungGC, true, \ "Trigger evacuation failure handling during young collection " \ "pauses") \ \ product(bool, G1GCAllocationFailureALotDuringMixedGC, true, \ "Force use of evacuation failure handling during mixed " \ "collection pauses") \ \ product(uint, G1GCAllocationFailureALotCSetPercent, 100, \ "The percentage of regions in the collection set starting " \ "from the beginning where the allocation failures are " \ "injected.") \ range(1, 100) #else #define GC_G1_EVACUATION_FAILURE_FLAGS(develop, \ develop_pd, \ product, \ product_pd, \ range, \ constraint) #endif // // Defines all globals flags used by the garbage-first compiler. // #define GC_G1_FLAGS(develop, \ develop_pd, \ product, \ product_pd, \ range, \ constraint) \ \ product(bool, G1UseAdaptiveIHOP, true, \ "Adaptively adjust the initiating heap occupancy from the " \ "initial value of InitiatingHeapOccupancyPercent. The policy " \ "attempts to start marking in time based on application " \ "behavior.") \ \ product(size_t, G1AdaptiveIHOPNumInitialSamples, 3, EXPERIMENTAL, \ "How many completed time periods from concurrent start to first " \ "mixed gc are required to use the input values for prediction " \ "of the optimal occupancy to start marking.") \ range(1, max_intx) \ \ product(uint, G1ConfidencePercent, 50, \ "Confidence level for MMU/pause predictions. A higher value " \ "means that G1 will use less safety margin for its predictions.") \ range(1, 100) \ \ product(uintx, G1SummarizeRSetStatsPeriod, 0, DIAGNOSTIC, \ "The period (in number of GCs) at which we will generate " \ "update buffer processing info " \ "(0 means do not periodically generate this info); " \ "it also requires that logging is enabled on the trace" \ "level for gc+remset") \ range(0, max_intx) \ \ product(double, G1ConcMarkStepDurationMillis, 10.0, \ "Target duration of individual concurrent marking steps " \ "in milliseconds.") \ range(1.0, DBL_MAX) \ \ product(uint, G1RefProcDrainInterval, 1000, \ "The number of discovered reference objects to process before " \ "draining concurrent marking work queues.") \ range(1, INT_MAX) \ \ product(bool, G1UseReferencePrecleaning, true, EXPERIMENTAL, \ "Concurrently preclean java.lang.ref.references instances " \ "before the Remark pause.") \ \ product(double, G1LastPLABAverageOccupancy, 50.0, EXPERIMENTAL, \ "The expected average occupancy of the last PLAB in " \ "percent.") \ range(0.001, 100.0) \ \ product(size_t, G1SATBBufferSize, 1*K, \ "Number of entries in an SATB log buffer.") \ constraint(G1SATBBufferSizeConstraintFunc, AtParse) \ \ develop(uintx, G1SATBProcessCompletedThreshold, 20, \ "Number of completed buffers that triggers log processing.") \ range(0, max_jint) \ \ product(uint, G1SATBBufferEnqueueingThresholdPercent, 60, \ "Before enqueueing them, each mutator thread tries to do some " \ "filtering on the SATB buffers it generates. If post-filtering " \ "the percentage of retained entries is over this threshold " \ "the buffer will be enqueued for processing.") \ range(0, 100) \ \ product(uint, G1ExpandByPercentOfAvailable, 20, EXPERIMENTAL, \ "When expanding, % of uncommitted space to claim.") \ range(0, 100) \ \ product(size_t, G1UpdateBufferSize, 256, \ "Size of an update buffer") \ constraint(G1UpdateBufferSizeConstraintFunc, AtParse) \ \ product(uint, G1RSetUpdatingPauseTimePercent, 10, \ "A target percentage of time that is allowed to be spend on " \ "processing remembered set update buffers during the collection " \ "pause.") \ range(0, 100) \ \ product(bool, G1UseConcRefinement, true, DIAGNOSTIC, \ "Control whether concurrent refinement is performed. " \ "Disabling effectively ignores G1RSetUpdatingPauseTimePercent") \ \ develop(uint, G1RemSetArrayOfCardsEntriesBase, 8, \ "Maximum number of entries per region in the Array of Cards " \ "card set container per MB of a heap region.") \ range(1, 65536) \ \ product(uint, G1RemSetArrayOfCardsEntries, 0, EXPERIMENTAL, \ "Maximum number of entries per Array of Cards card set " \ "container. Will be set ergonomically by default.") \ range(0, 65536) \ constraint(G1RemSetArrayOfCardsEntriesConstraintFunc,AfterErgo) \ \ product(uint, G1RemSetHowlMaxNumBuckets, 8, EXPERIMENTAL, \ "Maximum number of buckets per Howl card set container. The " \ "default gives at worst bitmaps of size 8k. This showed to be a " \ "good tradeoff between bitmap size (waste) and cacheability of " \ "the bucket array. Must be a power of two.") \ range(1, 1024) \ constraint(G1RemSetHowlMaxNumBucketsConstraintFunc,AfterErgo) \ \ product(uint, G1RemSetHowlNumBuckets, 0, EXPERIMENTAL, \ "Number of buckets per Howl card set container. Must be a power " \ "of two. Will be set ergonomically by default.") \ range(0, 1024) \ constraint(G1RemSetHowlNumBucketsConstraintFunc,AfterErgo) \ \ product(uint, G1RemSetCoarsenHowlBitmapToHowlFullPercent, 90, EXPERIMENTAL, \ "Percentage at which to coarsen a Howl bitmap to Howl full card " \ "set container.") \ range(1, 100) \ \ product(uint, G1RemSetCoarsenHowlToFullPercent, 90, EXPERIMENTAL, \ "Percentage at which to coarsen a Howl card set to Full card " \ "set container.") \ range(1, 100) \ \ develop(size_t, G1MaxVerifyFailures, SIZE_MAX, \ "The maximum number of liveness and remembered set verification " \ "failures to print per thread.") \ range(1, SIZE_MAX) \ \ product(uint, G1ReservePercent, 10, \ "It determines the minimum reserve we should have in the heap " \ "to minimize the probability of promotion failure.") \ range(0, 50) \ \ product(size_t, G1HeapRegionSize, 0, \ "Size of the G1 regions.") \ range(0, NOT_LP64(32*M) LP64_ONLY(512*M)) \ constraint(G1HeapRegionSizeConstraintFunc,AfterMemoryInit) \ \ product(uint, G1ConcRefinementThreads, 0, \ "The number of parallel remembered set update threads. " \ "Will be set ergonomically by default.") \ range(0, (max_jint-1)/wordSize) \ \ product(uint, G1MaxNewSizePercent, 60, EXPERIMENTAL, \ "Percentage (0-100) of the heap size to use as default " \ " maximum young gen size.") \ range(0, 100) \ constraint(G1MaxNewSizePercentConstraintFunc,AfterErgo) \ \ product(uint, G1NewSizePercent, 5, EXPERIMENTAL, \ "Percentage (0-100) of the heap size to use as default " \ "minimum young gen size.") \ range(0, 100) \ constraint(G1NewSizePercentConstraintFunc,AfterErgo) \ \ product(uint, G1MixedGCLiveThresholdPercent, 85, EXPERIMENTAL, \ "Threshold for regions to be considered for inclusion in the " \ "collection set of mixed GCs. " \ "Regions with live bytes exceeding this will not be collected.") \ range(0, 100) \ \ product(uint, G1RetainRegionLiveThresholdPercent, 85, EXPERIMENTAL, \ "Threshold for evacuation failed regions to be considered for " \ "inclusion in the collection set candidates." \ "Regions with live bytes exceeding this will not be retained.") \ range(0, 100) \ \ product(uint, G1HeapWastePercent, 5, \ "Amount of space, expressed as a percentage of the heap size, " \ "that G1 is willing not to collect to avoid expensive GCs.") \ range(0, 100) \ \ product(uintx, G1MixedGCCountTarget, 8, \ "The target number of mixed GCs after a marking cycle.") \ range(0, max_uintx) \ \ product(uint, G1EagerReclaimRemSetThreshold, 0, EXPERIMENTAL, \ "Maximum number of remembered set entries a humongous region " \ "otherwise eligible for eager reclaim may have to be a candidate "\ "for eager reclaim. Will be selected ergonomically by default.") \ \ product(size_t, G1RebuildRemSetChunkSize, 256 * K, EXPERIMENTAL, \ "Chunk size used for rebuilding the remembered set.") \ range(4 * K, 32 * M) \ \ product(uint, G1OldCSetRegionThresholdPercent, 10, EXPERIMENTAL, \ "An upper bound for the number of old CSet regions expressed " \ "as a percentage of the heap size.") \ range(0, 100) \ \ product(uint, G1OldCSetGroupSize, 5, EXPERIMENTAL, \ "The maximum number of old CSet regions in a collection group. " \ "All regions in a group will be evacuated in the same GC pause." \ "The first group calculated after marking from marking " \ "candidates may exceed this limit as it is calculated based on " \ "G1MixedGCCountTarget.") \ range(1, 256) \ \ product(bool, G1VerifyHeapRegionCodeRoots, false, DIAGNOSTIC, \ "Verify the code root lists attached to each heap region.") \ \ develop(bool, G1VerifyBitmaps, false, \ "Verifies the consistency of the marking bitmaps") \ \ product(uintx, G1PeriodicGCInterval, 0, MANAGEABLE, \ "Number of milliseconds after a previous GC to wait before " \ "triggering a periodic gc. A value of zero disables periodically "\ "enforced gc cycles.") \ \ product(bool, G1PeriodicGCInvokesConcurrent, true, \ "Determines the kind of periodic GC. Set to true to have G1 " \ "perform a concurrent GC as periodic GC, otherwise use a STW " \ "Full GC.") \ \ product(double, G1PeriodicGCSystemLoadThreshold, 0.0, MANAGEABLE, \ "Maximum recent system wide load as returned by the 1m value " \ "of getloadavg() at which G1 triggers a periodic GC. A load " \ "above this value cancels a given periodic GC. A value of zero " \ "disables this check.") \ range(0.0, (double)max_uintx) \ \ product(uint, G1RemSetFreeMemoryRescheduleDelayMillis, 10, EXPERIMENTAL, \ "Time after which the card set free memory task reschedules " \ "itself if there is work remaining.") \ range(1, UINT_MAX) \ \ product(double, G1RemSetFreeMemoryStepDurationMillis, 1, EXPERIMENTAL, \ "The amount of time that the free memory task should spend " \ "before a pause of G1RemSetFreeMemoryRescheduleDelayMillis " \ "length.") \ range(1e-3, 1e+6) \ \ product(double, G1RemSetFreeMemoryKeepExcessRatio, 0.1, EXPERIMENTAL, \ "The percentage of free card set memory that G1 should keep as " \ "percentage of the currently used memory.") \ range(0.0, 1.0) \ \ product(uint, G1RestoreRetainedRegionChunksPerWorker, 16, DIAGNOSTIC, \ "The number of chunks assigned per worker thread for " \ "retained region restore purposes.") \ range(1, 256) \ \ product(uint, G1NumCollectionsKeepPinned, 8, DIAGNOSTIC, \ "After how many GCs a region has been found pinned G1 should " \ "give up reclaiming it.") \ \ product(uint, G1NumCardsCostSampleThreshold, 1000, DIAGNOSTIC, \ "Threshold for the number of cards when reporting remembered set "\ "card cost related prediction samples. A sample must involve " \ "the same or more than that number of cards to be used.") \ \ product(uint, G1NumCodeRootsCostSampleThreshold, 100, DIAGNOSTIC, \ "Threshold for the number of code roots when reporting code root "\ "scan cost related prediction samples. A sample must involve " \ "the same or more than this number of code roots to be used.") \ \ GC_G1_EVACUATION_FAILURE_FLAGS(develop, \ develop_pd, \ product, \ product_pd, \ range, \ constraint) // end of GC_G1_FLAGS #endif // SHARE_GC_G1_G1_GLOBALS_HPP