--- old/src/hotspot/share/gc/g1/g1_globals.hpp 2020-04-05 21:35:03.446403237 -0700 +++ new/src/hotspot/share/gc/g1/g1_globals.hpp 2020-04-05 21:35:03.094389987 -0700 @@ -28,296 +28,285 @@ #include "runtime/globals_shared.hpp" // -// Defines all globals flags used by the garbage-first compiler. +// Declare all globals flags used by the garbage-first compiler. // -#define GC_G1_FLAGS(develop, \ - develop_pd, \ - product, \ - product_pd, \ - diagnostic, \ - diagnostic_pd, \ - experimental, \ - notproduct, \ - manageable, \ - product_rw, \ - lp64_product, \ - 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.") \ - \ - experimental(size_t, G1AdaptiveIHOPNumInitialSamples, 3, \ - "How many completed time periods from initial mark 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(uintx, G1ConfidencePercent, 50, \ - "Confidence level for MMU/pause predictions") \ - range(0, 100) \ - \ - diagnostic(intx, G1SummarizeRSetStatsPeriod, 0, \ - "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) \ - \ - experimental(bool, G1UseReferencePrecleaning, true, \ - "Concurrently preclean java.lang.ref.references instances " \ - "before the Remark pause.") \ - \ - experimental(double, G1LastPLABAverageOccupancy, 50.0, \ - "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.") \ - range(1, max_uintx) \ - \ - develop(intx, G1SATBProcessCompletedThreshold, 20, \ - "Number of completed buffers that triggers log processing.") \ - range(0, max_jint) \ - \ - product(uintx, 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. A value of 0 " \ - "specifies that mutator threads should not do such filtering.") \ - range(0, 100) \ - \ - experimental(intx, G1ExpandByPercentOfAvailable, 20, \ - "When expanding, % of uncommitted space to claim.") \ - range(0, 100) \ - \ - product(size_t, G1UpdateBufferSize, 256, \ - "Size of an update buffer") \ - range(1, NOT_LP64(32*M) LP64_ONLY(1*G)) \ - \ - product(size_t, G1ConcRefinementYellowZone, 0, \ - "Number of enqueued update buffers that will " \ - "trigger concurrent processing. Will be selected ergonomically " \ - "by default.") \ - range(0, max_intx) \ - \ - product(size_t, G1ConcRefinementRedZone, 0, \ - "Maximum number of enqueued update buffers before mutator " \ - "threads start processing new ones instead of enqueueing them. " \ - "Will be selected ergonomically by default.") \ - range(0, max_intx) \ - \ - product(size_t, G1ConcRefinementGreenZone, 0, \ - "The number of update buffers that are left in the queue by the " \ - "concurrent processing threads. Will be selected ergonomically " \ - "by default.") \ - range(0, max_intx) \ - \ - product(uintx, G1ConcRefinementServiceIntervalMillis, 300, \ - "The last concurrent refinement thread wakes up every " \ - "specified number of milliseconds to do miscellaneous work.") \ - range(0, max_jint) \ - \ - product(size_t, G1ConcRefinementThresholdStep, 2, \ - "Each time the rset update queue increases by this amount " \ - "activate the next refinement thread if available. " \ - "The actual step size will be selected ergonomically by " \ - "default, with this value used to determine a lower bound.") \ - range(1, SIZE_MAX) \ - \ - product(intx, G1RSetUpdatingPauseTimePercent, 10, \ - "A target percentage of time that is allowed to be spend on " \ - "process RS update buffers during the collection pause.") \ - range(0, 100) \ - \ - product(bool, G1UseAdaptiveConcRefinement, true, \ - "Select green, yellow and red zones adaptively to meet the " \ - "the pause requirements.") \ - \ - product(size_t, G1ConcRSLogCacheSize, 10, \ - "Log base 2 of the length of conc RS hot-card cache.") \ - range(0, 27) \ - \ - product(uintx, G1ConcRSHotCardLimit, 4, \ - "The threshold that defines (>=) a hot card.") \ - range(0, max_jubyte) \ - \ - develop(intx, G1RSetRegionEntriesBase, 256, \ - "Max number of regions in a fine-grain table per MB.") \ - range(1, max_jint/wordSize) \ - \ - product(intx, G1RSetRegionEntries, 0, \ - "Max number of regions for which we keep bitmaps." \ - "Will be set ergonomically by default") \ - range(0, max_jint/wordSize) \ - constraint(G1RSetRegionEntriesConstraintFunc,AfterErgo) \ - \ - develop(intx, G1RSetSparseRegionEntriesBase, 4, \ - "Max number of entries per region in a sparse table " \ - "per MB.") \ - range(1, max_jint/wordSize) \ - \ - product(intx, G1RSetSparseRegionEntries, 0, \ - "Max number of entries per region in a sparse table." \ - "Will be set ergonomically by default.") \ - range(0, max_jint/wordSize) \ - constraint(G1RSetSparseRegionEntriesConstraintFunc,AfterErgo) \ - \ - develop(intx, G1MaxVerifyFailures, -1, \ - "The maximum number of verification failures to print. " \ - "-1 means print all.") \ - range(-1, max_jint) \ - \ - product(uintx, 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, 32*M) \ - constraint(G1HeapRegionSizeConstraintFunc,AfterMemoryInit) \ - \ - product(uint, G1ConcRefinementThreads, 0, \ - "The number of parallel rem set update threads. " \ - "Will be set ergonomically by default.") \ - range(0, (max_jint-1)/wordSize) \ - \ - develop(bool, G1VerifyCTCleanup, false, \ - "Verify card table cleanup.") \ - \ - develop(uintx, G1DummyRegionsPerGC, 0, \ - "The number of dummy regions G1 will allocate at the end of " \ - "each evacuation pause in order to artificially fill up the " \ - "heap and stress the marking implementation.") \ - \ - develop(bool, G1ExitOnExpansionFailure, false, \ - "Raise a fatal VM exit out of memory failure in the event " \ - " that heap expansion fails due to running out of swap.") \ - \ - experimental(uintx, G1MaxNewSizePercent, 60, \ - "Percentage (0-100) of the heap size to use as default " \ - " maximum young gen size.") \ - range(0, 100) \ - constraint(G1MaxNewSizePercentConstraintFunc,AfterErgo) \ - \ - experimental(uintx, G1NewSizePercent, 5, \ - "Percentage (0-100) of the heap size to use as default " \ - "minimum young gen size.") \ - range(0, 100) \ - constraint(G1NewSizePercentConstraintFunc,AfterErgo) \ - \ - experimental(uintx, G1MixedGCLiveThresholdPercent, 85, \ - "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(uintx, 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) \ - \ - experimental(bool, G1EagerReclaimHumongousObjects, true, \ - "Try to reclaim dead large objects at every young GC.") \ - \ - experimental(bool, G1EagerReclaimHumongousObjectsWithStaleRefs, true, \ - "Try to reclaim dead large objects that have a few stale " \ - "references at every young GC.") \ - \ - experimental(size_t, G1RebuildRemSetChunkSize, 256 * K, \ - "Chunk size used for rebuilding the remembered set.") \ - range(4 * K, 32 * M) \ - \ - experimental(uintx, G1OldCSetRegionThresholdPercent, 10, \ - "An upper bound for the number of old CSet regions expressed " \ - "as a percentage of the heap size.") \ - range(0, 100) \ - \ - notproduct(bool, G1EvacuationFailureALot, false, \ - "Force use of evacuation failure handling during certain " \ - "evacuation pauses") \ - \ - develop(uintx, G1EvacuationFailureALotCount, 1000, \ - "Number of successful evacuations between evacuation failures " \ - "occurring at object copying") \ - \ - develop(uintx, G1EvacuationFailureALotInterval, 5, \ - "Total collections between forced triggering of evacuation " \ - "failures") \ - \ - develop(bool, G1EvacuationFailureALotDuringConcMark, true, \ - "Force use of evacuation failure handling during evacuation " \ - "pauses when marking is in progress") \ - \ - develop(bool, G1EvacuationFailureALotDuringInitialMark, true, \ - "Force use of evacuation failure handling during initial mark " \ - "evacuation pauses") \ - \ - develop(bool, G1EvacuationFailureALotDuringYoungGC, true, \ - "Force use of evacuation failure handling during young " \ - "evacuation pauses") \ - \ - develop(bool, G1EvacuationFailureALotDuringMixedGC, true, \ - "Force use of evacuation failure handling during mixed " \ - "evacuation pauses") \ - \ - diagnostic(bool, G1VerifyRSetsDuringFullGC, false, \ - "If true, perform verification of each heap region's " \ - "remembered set when verifying the heap during a full GC.") \ - \ - diagnostic(bool, G1VerifyHeapRegionCodeRoots, false, \ - "Verify the code root lists attached to each heap region.") \ - \ - develop(bool, G1VerifyBitmaps, false, \ - "Verifies the consistency of the marking bitmaps") \ - \ - manageable(uintx, G1PeriodicGCInterval, 0, \ - "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.") \ - \ - manageable(double, G1PeriodicGCSystemLoadThreshold, 0.0, \ - "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) \ - \ - experimental(uintx, G1YoungExpansionBufferPercent, 10, \ - "When heterogenous heap is enabled by AllocateOldGenAt " \ - "option, after every GC, young gen is re-sized which " \ - "involves system calls to commit/uncommit memory. To " \ - "reduce these calls, we keep a buffer of extra regions to " \ - "absorb small changes in young gen length. This flag takes " \ - "the buffer size as an percentage of young gen length") \ - range(0, 100) \ +#include "utilities/macros.hpp" +#if INCLUDE_G1GC +#include "runtime/flags/jvmFlag.hpp" +PRODUCT_FLAG(bool, G1UseAdaptiveIHOP, true, JVMFlag::DEFAULT, + "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_FLAG(size_t, G1AdaptiveIHOPNumInitialSamples, 3, JVMFlag::EXPERIMENTAL | JVMFlag::RANGE, + "How many completed time periods from initial mark to first " + "mixed gc are required to use the input values for prediction " + "of the optimal occupancy to start marking."); + FLAG_RANGE( G1AdaptiveIHOPNumInitialSamples, 1, max_intx); + +PRODUCT_FLAG(uintx, G1ConfidencePercent, 50, JVMFlag::RANGE, + "Confidence level for MMU/pause predictions"); + FLAG_RANGE( G1ConfidencePercent, 0, 100); + +PRODUCT_FLAG(intx, G1SummarizeRSetStatsPeriod, 0, JVMFlag::DIAGNOSTIC | JVMFlag::RANGE, + "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"); + FLAG_RANGE( G1SummarizeRSetStatsPeriod, 0, max_intx); + +PRODUCT_FLAG(double, G1ConcMarkStepDurationMillis, 10.0, JVMFlag::RANGE, + "Target duration of individual concurrent marking steps " + "in milliseconds."); + FLAG_RANGE( G1ConcMarkStepDurationMillis, 1.0, DBL_MAX); + +PRODUCT_FLAG(uint, G1RefProcDrainInterval, 1000, JVMFlag::RANGE, + "The number of discovered reference objects to process before " + "draining concurrent marking work queues."); + FLAG_RANGE( G1RefProcDrainInterval, 1, INT_MAX); + +PRODUCT_FLAG(bool, G1UseReferencePrecleaning, true, JVMFlag::EXPERIMENTAL, + "Concurrently preclean java.lang.ref.references instances " + "before the Remark pause."); + +PRODUCT_FLAG(double, G1LastPLABAverageOccupancy, 50.0, JVMFlag::EXPERIMENTAL | JVMFlag::RANGE, + "The expected average occupancy of the last PLAB in " + "percent."); + FLAG_RANGE( G1LastPLABAverageOccupancy, 0.001, 100.0); + +PRODUCT_FLAG(size_t, G1SATBBufferSize, 1*K, JVMFlag::RANGE, + "Number of entries in an SATB log buffer."); + FLAG_RANGE( G1SATBBufferSize, 1, max_uintx); + +DEVELOP_FLAG(intx, G1SATBProcessCompletedThreshold, 20, JVMFlag::RANGE, + "Number of completed buffers that triggers log processing."); + FLAG_RANGE( G1SATBProcessCompletedThreshold, 0, max_jint); + +PRODUCT_FLAG(uintx, G1SATBBufferEnqueueingThresholdPercent, 60, JVMFlag::RANGE, + "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. A value of 0 " + "specifies that mutator threads should not do such filtering."); + FLAG_RANGE( G1SATBBufferEnqueueingThresholdPercent, 0, 100); + +PRODUCT_FLAG(intx, G1ExpandByPercentOfAvailable, 20, JVMFlag::EXPERIMENTAL | JVMFlag::RANGE, + "When expanding, % of uncommitted space to claim."); + FLAG_RANGE( G1ExpandByPercentOfAvailable, 0, 100); + +PRODUCT_FLAG(size_t, G1UpdateBufferSize, 256, JVMFlag::RANGE, + "Size of an update buffer"); + FLAG_RANGE( G1UpdateBufferSize, 1, NOT_LP64(32*M) LP64_ONLY(1*G)); + +PRODUCT_FLAG(size_t, G1ConcRefinementYellowZone, 0, JVMFlag::RANGE, + "Number of enqueued update buffers that will " + "trigger concurrent processing. Will be selected ergonomically " + "by default."); + FLAG_RANGE( G1ConcRefinementYellowZone, 0, max_intx); + +PRODUCT_FLAG(size_t, G1ConcRefinementRedZone, 0, JVMFlag::RANGE, + "Maximum number of enqueued update buffers before mutator " + "threads start processing new ones instead of enqueueing them. " + "Will be selected ergonomically by default."); + FLAG_RANGE( G1ConcRefinementRedZone, 0, max_intx); + +PRODUCT_FLAG(size_t, G1ConcRefinementGreenZone, 0, JVMFlag::RANGE, + "The number of update buffers that are left in the queue by the " + "concurrent processing threads. Will be selected ergonomically " + "by default."); + FLAG_RANGE( G1ConcRefinementGreenZone, 0, max_intx); + +PRODUCT_FLAG(uintx, G1ConcRefinementServiceIntervalMillis, 300, JVMFlag::RANGE, + "The last concurrent refinement thread wakes up every " + "specified number of milliseconds to do miscellaneous work."); + FLAG_RANGE( G1ConcRefinementServiceIntervalMillis, 0, max_jint); + +PRODUCT_FLAG(size_t, G1ConcRefinementThresholdStep, 2, JVMFlag::RANGE, + "Each time the rset update queue increases by this amount " + "activate the next refinement thread if available. " + "The actual step size will be selected ergonomically by " + "default, with this value used to determine a lower bound."); + FLAG_RANGE( G1ConcRefinementThresholdStep, 1, SIZE_MAX); + +PRODUCT_FLAG(intx, G1RSetUpdatingPauseTimePercent, 10, JVMFlag::RANGE, + "A target percentage of time that is allowed to be spend on " + "process RS update buffers during the collection pause."); + FLAG_RANGE( G1RSetUpdatingPauseTimePercent, 0, 100); + +PRODUCT_FLAG(bool, G1UseAdaptiveConcRefinement, true, JVMFlag::DEFAULT, + "Select green, yellow and red zones adaptively to meet the " + "the pause requirements."); + +PRODUCT_FLAG(size_t, G1ConcRSLogCacheSize, 10, JVMFlag::RANGE, + "Log base 2 of the length of conc RS hot-card cache."); + FLAG_RANGE( G1ConcRSLogCacheSize, 0, 27); + +PRODUCT_FLAG(uintx, G1ConcRSHotCardLimit, 4, JVMFlag::RANGE, + "The threshold that defines (>=) a hot card."); + FLAG_RANGE( G1ConcRSHotCardLimit, 0, max_jubyte); + +DEVELOP_FLAG(intx, G1RSetRegionEntriesBase, 256, JVMFlag::RANGE, + "Max number of regions in a fine-grain table per MB."); + FLAG_RANGE( G1RSetRegionEntriesBase, 1, max_jint/wordSize); + +PRODUCT_FLAG(intx, G1RSetRegionEntries, 0, JVMFlag::RANGE | JVMFlag::CONSTRAINT, + "Max number of regions for which we keep bitmaps." + "Will be set ergonomically by default"); + FLAG_RANGE( G1RSetRegionEntries, 0, max_jint/wordSize); + FLAG_CONSTRAINT( G1RSetRegionEntries, (void*)G1RSetRegionEntriesConstraintFunc, JVMFlag::AfterErgo); + +DEVELOP_FLAG(intx, G1RSetSparseRegionEntriesBase, 4, JVMFlag::RANGE, + "Max number of entries per region in a sparse table " + "per MB."); + FLAG_RANGE( G1RSetSparseRegionEntriesBase, 1, max_jint/wordSize); + +PRODUCT_FLAG(intx, G1RSetSparseRegionEntries, 0, JVMFlag::RANGE | JVMFlag::CONSTRAINT, + "Max number of entries per region in a sparse table." + "Will be set ergonomically by default."); + FLAG_RANGE( G1RSetSparseRegionEntries, 0, max_jint/wordSize); + FLAG_CONSTRAINT( G1RSetSparseRegionEntries, (void*)G1RSetSparseRegionEntriesConstraintFunc, JVMFlag::AfterErgo); + +DEVELOP_FLAG(intx, G1MaxVerifyFailures, -1, JVMFlag::RANGE, + "The maximum number of verification failures to print. " + "-1 means print all."); + FLAG_RANGE( G1MaxVerifyFailures, -1, max_jint); + +PRODUCT_FLAG(uintx, G1ReservePercent, 10, JVMFlag::RANGE, + "It determines the minimum reserve we should have in the heap " + "to minimize the probability of promotion failure."); + FLAG_RANGE( G1ReservePercent, 0, 50); + +PRODUCT_FLAG(size_t, G1HeapRegionSize, 0, JVMFlag::RANGE | JVMFlag::CONSTRAINT, + "Size of the G1 regions."); + FLAG_RANGE( G1HeapRegionSize, 0, 32*M); + FLAG_CONSTRAINT( G1HeapRegionSize, (void*)G1HeapRegionSizeConstraintFunc, JVMFlag::AfterMemoryInit); + +PRODUCT_FLAG(uint, G1ConcRefinementThreads, 0, JVMFlag::RANGE, + "The number of parallel rem set update threads. " + "Will be set ergonomically by default."); + FLAG_RANGE( G1ConcRefinementThreads, 0, (max_jint-1)/wordSize); + +DEVELOP_FLAG(bool, G1VerifyCTCleanup, false, JVMFlag::DEFAULT, + "Verify card table cleanup."); + +DEVELOP_FLAG(uintx, G1DummyRegionsPerGC, 0, JVMFlag::DEFAULT, + "The number of dummy regions G1 will allocate at the end of " + "each evacuation pause in order to artificially fill up the " + "heap and stress the marking implementation."); + +DEVELOP_FLAG(bool, G1ExitOnExpansionFailure, false, JVMFlag::DEFAULT, + "Raise a fatal VM exit out of memory failure in the event " + " that heap expansion fails due to running out of swap."); + +PRODUCT_FLAG(uintx, G1MaxNewSizePercent, 60, JVMFlag::EXPERIMENTAL | JVMFlag::RANGE | JVMFlag::CONSTRAINT, + "Percentage (0-100) of the heap size to use as default " + " maximum young gen size."); + FLAG_RANGE( G1MaxNewSizePercent, 0, 100); + FLAG_CONSTRAINT( G1MaxNewSizePercent, (void*)G1MaxNewSizePercentConstraintFunc, JVMFlag::AfterErgo); + +PRODUCT_FLAG(uintx, G1NewSizePercent, 5, JVMFlag::EXPERIMENTAL | JVMFlag::RANGE | JVMFlag::CONSTRAINT, + "Percentage (0-100) of the heap size to use as default " + "minimum young gen size."); + FLAG_RANGE( G1NewSizePercent, 0, 100); + FLAG_CONSTRAINT( G1NewSizePercent, (void*)G1NewSizePercentConstraintFunc, JVMFlag::AfterErgo); + +PRODUCT_FLAG(uintx, G1MixedGCLiveThresholdPercent, 85, JVMFlag::EXPERIMENTAL | JVMFlag::RANGE, + "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."); + FLAG_RANGE( G1MixedGCLiveThresholdPercent, 0, 100); + +PRODUCT_FLAG(uintx, G1HeapWastePercent, 5, JVMFlag::RANGE, + "Amount of space, expressed as a percentage of the heap size, " + "that G1 is willing not to collect to avoid expensive GCs."); + FLAG_RANGE( G1HeapWastePercent, 0, 100); + +PRODUCT_FLAG(uintx, G1MixedGCCountTarget, 8, JVMFlag::RANGE, + "The target number of mixed GCs after a marking cycle."); + FLAG_RANGE( G1MixedGCCountTarget, 0, max_uintx); + +PRODUCT_FLAG(bool, G1EagerReclaimHumongousObjects, true, JVMFlag::EXPERIMENTAL, + "Try to reclaim dead large objects at every young GC."); + +PRODUCT_FLAG(bool, G1EagerReclaimHumongousObjectsWithStaleRefs, true, JVMFlag::EXPERIMENTAL, + "Try to reclaim dead large objects that have a few stale " + "references at every young GC."); + +PRODUCT_FLAG(size_t, G1RebuildRemSetChunkSize, 256 * K, JVMFlag::EXPERIMENTAL | JVMFlag::RANGE, + "Chunk size used for rebuilding the remembered set."); + FLAG_RANGE( G1RebuildRemSetChunkSize, 4 * K, 32 * M); + +PRODUCT_FLAG(uintx, G1OldCSetRegionThresholdPercent, 10, JVMFlag::EXPERIMENTAL | JVMFlag::RANGE, + "An upper bound for the number of old CSet regions expressed " + "as a percentage of the heap size."); + FLAG_RANGE( G1OldCSetRegionThresholdPercent, 0, 100); + +NOTPROD_FLAG(bool, G1EvacuationFailureALot, false, JVMFlag::DEFAULT, + "Force use of evacuation failure handling during certain " + "evacuation pauses"); + +DEVELOP_FLAG(uintx, G1EvacuationFailureALotCount, 1000, JVMFlag::DEFAULT, + "Number of successful evacuations between evacuation failures " + "occurring at object copying"); + +DEVELOP_FLAG(uintx, G1EvacuationFailureALotInterval, 5, JVMFlag::DEFAULT, + "Total collections between forced triggering of evacuation " + "failures"); + +DEVELOP_FLAG(bool, G1EvacuationFailureALotDuringConcMark, true, JVMFlag::DEFAULT, + "Force use of evacuation failure handling during evacuation " + "pauses when marking is in progress"); + +DEVELOP_FLAG(bool, G1EvacuationFailureALotDuringInitialMark, true, JVMFlag::DEFAULT, + "Force use of evacuation failure handling during initial mark " + "evacuation pauses"); + +DEVELOP_FLAG(bool, G1EvacuationFailureALotDuringYoungGC, true, JVMFlag::DEFAULT, + "Force use of evacuation failure handling during young " + "evacuation pauses"); + +DEVELOP_FLAG(bool, G1EvacuationFailureALotDuringMixedGC, true, JVMFlag::DEFAULT, + "Force use of evacuation failure handling during mixed " + "evacuation pauses"); + +PRODUCT_FLAG(bool, G1VerifyRSetsDuringFullGC, false, JVMFlag::DIAGNOSTIC, + "If true, perform verification of each heap region's " + "remembered set when verifying the heap during a full GC."); + +PRODUCT_FLAG(bool, G1VerifyHeapRegionCodeRoots, false, JVMFlag::DIAGNOSTIC, + "Verify the code root lists attached to each heap region."); + +DEVELOP_FLAG(bool, G1VerifyBitmaps, false, JVMFlag::DEFAULT, + "Verifies the consistency of the marking bitmaps"); + +PRODUCT_FLAG(uintx, G1PeriodicGCInterval, 0, JVMFlag::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_FLAG(bool, G1PeriodicGCInvokesConcurrent, true, JVMFlag::DEFAULT, + "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_FLAG(double, G1PeriodicGCSystemLoadThreshold, 0.0, JVMFlag::MANAGEABLE | JVMFlag::RANGE, + "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."); + FLAG_RANGE( G1PeriodicGCSystemLoadThreshold, 0.0, (double)max_uintx); + +PRODUCT_FLAG(uintx, G1YoungExpansionBufferPercent, 10, JVMFlag::EXPERIMENTAL | JVMFlag::RANGE, + "When heterogenous heap is enabled by AllocateOldGenAt " + "option, after every GC, young gen is re-sized which " + "involves system calls to commit/uncommit memory. To " + "reduce these calls, we keep a buffer of extra regions to " + "absorb small changes in young gen length. This flag takes " + "the buffer size as an percentage of young gen length"); + FLAG_RANGE( G1YoungExpansionBufferPercent, 0, 100); +#endif // INCLUDE_G1GC #endif // SHARE_GC_G1_G1_GLOBALS_HPP