view src/share/vm/gc_implementation/g1/g1_globals.hpp @ 2346:e1162778c1c8

7009266: G1: assert(obj->is_oop_or_null(true )) failed: Error Summary: A referent object that is only weakly reachable at the start of concurrent marking but is re-attached to the strongly reachable object graph during marking may not be marked as live. This can cause the reference object to be processed prematurely and leave dangling pointers to the referent object. Implement a read barrier for the java.lang.ref.Reference::referent field by intrinsifying the Reference.get() method, and intercepting accesses though JNI, reflection, and Unsafe, so that when a non-null referent object is read it is also logged in an SATB buffer. Reviewed-by: kvn, iveresov, never, tonyp, dholmes
author johnc
date Thu, 07 Apr 2011 09:53:20 -0700
parents 8f1042ff784d
children 49a67202bc67
line wrap: on
line source
/*
 * Copyright (c) 2001, 2011, 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_VM_GC_IMPLEMENTATION_G1_G1_GLOBALS_HPP
#define SHARE_VM_GC_IMPLEMENTATION_G1_G1_GLOBALS_HPP

#include "runtime/globals.hpp"

//
// Defines all globals flags used by the garbage-first compiler.
//

#define G1_FLAGS(develop, develop_pd, product, product_pd, diagnostic, experimental, notproduct, manageable, product_rw) \
                                                                            \
  product(intx, G1ConfidencePercent, 50,                                    \
          "Confidence level for MMU/pause predictions")                     \
                                                                            \
  develop(intx, G1MarkingOverheadPercent, 0,                                \
          "Overhead of concurrent marking")                                 \
                                                                            \
  develop(bool, G1Gen, true,                                                \
          "If true, it will enable the generational G1")                    \
                                                                            \
  develop(intx, G1PolicyVerbose, 0,                                         \
          "The verbosity level on G1 policy decisions")                     \
                                                                            \
  develop(intx, G1MarkingVerboseLevel, 0,                                   \
          "Level (0-4) of verboseness of the marking code")                 \
                                                                            \
  develop(bool, G1PrintReachableAtInitialMark, false,                       \
          "Reachable object dump at the initial mark pause")                \
                                                                            \
  develop(bool, G1VerifyDuringGCPrintReachable, false,                      \
          "If conc mark verification fails, dump reachable objects")        \
                                                                            \
  develop(ccstr, G1PrintReachableBaseFile, NULL,                            \
          "The base file name for the reachable object dumps")              \
                                                                            \
  develop(bool, G1TraceMarkStackOverflow, false,                            \
          "If true, extra debugging code for CM restart for ovflw.")        \
                                                                            \
  develop(intx, G1PausesBtwnConcMark, -1,                                   \
          "If positive, fixed number of pauses between conc markings")      \
                                                                            \
  diagnostic(bool, G1SummarizeConcMark, false,                              \
          "Summarize concurrent mark info")                                 \
                                                                            \
  diagnostic(bool, G1SummarizeRSetStats, false,                             \
          "Summarize remembered set processing info")                       \
                                                                            \
  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 -XX:+G1SummarizeRSetStats")                     \
                                                                            \
  diagnostic(bool, G1TraceConcRefinement, false,                            \
          "Trace G1 concurrent refinement")                                 \
                                                                            \
  product(intx, G1MarkRegionStackSize, 1024 * 1024,                         \
          "Size of the region stack for concurrent marking.")               \
                                                                            \
  product(double, G1ConcMarkStepDurationMillis, 10.0,                       \
          "Target duration of individual concurrent marking steps "         \
          "in milliseconds.")                                               \
                                                                            \
  product(intx, G1RefProcDrainInterval, 10,                                 \
          "The number of discovered reference objects to process before "   \
          "draining concurrent marking work queues.")                       \
                                                                            \
  experimental(bool, G1UseConcMarkReferenceProcessing, true,                \
          "If true, enable reference discovery during concurrent "          \
          "marking and reference processing at the end of remark.")         \
                                                                            \
  product(intx, G1SATBBufferSize, 1*K,                                      \
          "Number of entries in an SATB log buffer.")                       \
                                                                            \
  develop(intx, G1SATBProcessCompletedThreshold, 20,                        \
          "Number of completed buffers that triggers log processing.")      \
                                                                            \
  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.")   \
                                                                            \
  develop(intx, G1ExtraRegionSurvRate, 33,                                  \
          "If the young survival rate is S, and there's room left in "      \
          "to-space, we will allow regions whose survival rate is up to "   \
          "S + (1 - S)*X, where X is this parameter (as a fraction.)")      \
                                                                            \
  develop(intx, G1InitYoungSurvRatio, 50,                                   \
          "Expected Survival Rate for newly allocated bytes")               \
                                                                            \
  develop(bool, G1SATBPrintStubs, false,                                    \
          "If true, print generated stubs for the SATB barrier")            \
                                                                            \
  experimental(intx, G1ExpandByPercentOfAvailable, 20,                      \
          "When expanding, % of uncommitted space to claim.")               \
                                                                            \
  develop(bool, G1RSBarrierRegionFilter, true,                              \
          "If true, generate region filtering code in RS barrier")          \
                                                                            \
  develop(bool, G1RSBarrierNullFilter, true,                                \
          "If true, generate null-pointer filtering code in RS barrier")    \
                                                                            \
  develop(bool, G1PrintCTFilterStats, false,                                \
          "If true, print stats on RS filtering effectiveness")             \
                                                                            \
  develop(bool, G1DeferredRSUpdate, true,                                   \
          "If true, use deferred RS updates")                               \
                                                                            \
  develop(bool, G1RSLogCheckCardTable, false,                               \
          "If true, verify that no dirty cards remain after RS log "        \
          "processing.")                                                    \
                                                                            \
  develop(bool, G1RSCountHisto, false,                                      \
          "If true, print a histogram of RS occupancies after each pause")  \
                                                                            \
  product(bool, G1PrintRegionLivenessInfo, false,                           \
          "Prints the liveness information for all regions in the heap "    \
          "at the end of a marking cycle.")                                 \
                                                                            \
  develop(bool, G1PrintParCleanupStats, false,                              \
          "When true, print extra stats about parallel cleanup.")           \
                                                                            \
  product(intx, G1UpdateBufferSize, 256,                                    \
          "Size of an update buffer")                                       \
                                                                            \
  product(intx, G1ConcRefinementYellowZone, 0,                              \
          "Number of enqueued update buffers that will "                    \
          "trigger concurrent processing. Will be selected ergonomically "  \
          "by default.")                                                    \
                                                                            \
  product(intx, 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. Zero will disable "   \
          "concurrent processing.")                                         \
                                                                            \
  product(intx, G1ConcRefinementGreenZone, 0,                               \
          "The number of update buffers that are left in the queue by the " \
          "concurrent processing threads. Will be selected ergonomically "  \
          "by default.")                                                    \
                                                                            \
  product(intx, G1ConcRefinementServiceIntervalMillis, 300,                 \
          "The last concurrent refinement thread wakes up every "           \
          "specified number of milliseconds to do miscellaneous work.")     \
                                                                            \
  product(intx, G1ConcRefinementThresholdStep, 0,                           \
          "Each time the rset update queue increases by this amount "       \
          "activate the next refinement thread if available. "              \
          "Will be selected ergonomically by default.")                     \
                                                                            \
  product(intx, G1RSetUpdatingPauseTimePercent, 10,                         \
          "A target percentage of time that is allowed to be spend on "     \
          "process RS update buffers during the collection pause.")         \
                                                                            \
  product(bool, G1UseAdaptiveConcRefinement, true,                          \
          "Select green, yellow and red zones adaptively to meet the "      \
          "the pause requirements.")                                        \
                                                                            \
  develop(intx, G1ConcRSLogCacheSize, 10,                                   \
          "Log base 2 of the length of conc RS hot-card cache.")            \
                                                                            \
  develop(intx, G1ConcRSHotCardLimit, 4,                                    \
          "The threshold that defines (>=) a hot card.")                    \
                                                                            \
  develop(intx, G1MaxHotCardCountSizePercent, 25,                           \
          "The maximum size of the hot card count cache as a "              \
          "percentage of the number of cards for the maximum heap.")        \
                                                                            \
  develop(bool, G1PrintOopAppls, false,                                     \
          "When true, print applications of closures to external locs.")    \
                                                                            \
  develop(intx, G1RSetRegionEntriesBase, 256,                               \
          "Max number of regions in a fine-grain table per MB.")            \
                                                                            \
  product(intx, G1RSetRegionEntries, 0,                                     \
          "Max number of regions for which we keep bitmaps."                \
          "Will be set ergonomically by default")                           \
                                                                            \
  develop(intx, G1RSetSparseRegionEntriesBase, 4,                           \
          "Max number of entries per region in a sparse table "             \
          "per MB.")                                                        \
                                                                            \
  product(intx, G1RSetSparseRegionEntries, 0,                               \
          "Max number of entries per region in a sparse table."             \
          "Will be set ergonomically by default.")                          \
                                                                            \
  develop(bool, G1RecordHRRSOops, false,                                    \
          "When true, record recent calls to rem set operations.")          \
                                                                            \
  develop(bool, G1RecordHRRSEvents, false,                                  \
          "When true, record recent calls to rem set operations.")          \
                                                                            \
  develop(intx, G1MaxVerifyFailures, -1,                                    \
          "The maximum number of verification failrues to print.  "         \
          "-1 means print all.")                                            \
                                                                            \
  develop(bool, G1ScrubRemSets, true,                                       \
          "When true, do RS scrubbing after cleanup.")                      \
                                                                            \
  develop(bool, G1RSScrubVerbose, false,                                    \
          "When true, do RS scrubbing with verbose output.")                \
                                                                            \
  develop(bool, G1YoungSurvRateVerbose, false,                              \
          "print out the survival rate of young regions according to age.") \
                                                                            \
  develop(intx, G1YoungSurvRateNumRegionsSummary, 0,                        \
          "the number of regions for which we'll print a surv rate "        \
          "summary.")                                                       \
                                                                            \
  product(intx, G1ReservePercent, 10,                                       \
          "It determines the minimum reserve we should have in the heap "   \
          "to minimize the probability of promotion failure.")              \
                                                                            \
  diagnostic(bool, G1PrintHeapRegions, false,                               \
          "If set G1 will print information on which regions are being "    \
          "allocated and which are reclaimed.")                             \
                                                                            \
  develop(bool, G1HRRSUseSparseTable, true,                                 \
          "When true, use sparse table to save space.")                     \
                                                                            \
  develop(bool, G1HRRSFlushLogBuffersOnVerify, false,                       \
          "Forces flushing of log buffers before verification.")            \
                                                                            \
  develop(bool, G1FailOnFPError, false,                                     \
          "When set, G1 will fail when it encounters an FP 'error', "       \
          "so as to allow debugging")                                       \
                                                                            \
  develop(bool, G1FixedTenuringThreshold, false,                            \
          "When set, G1 will not adjust the tenuring threshold")            \
                                                                            \
  develop(bool, G1FixedEdenSize, false,                                     \
          "When set, G1 will not allocate unused survivor space regions")   \
                                                                            \
  develop(uintx, G1FixedSurvivorSpaceSize, 0,                               \
          "If non-0 is the size of the G1 survivor space, "                 \
          "otherwise SurvivorRatio is used to determine the size")          \
                                                                            \
  product(uintx, G1HeapRegionSize, 0,                                       \
          "Size of the G1 regions.")                                        \
                                                                            \
  experimental(bool, G1UseParallelRSetUpdating, true,                       \
          "Enables the parallelization of remembered set updating "         \
          "during evacuation pauses")                                       \
                                                                            \
  experimental(bool, G1UseParallelRSetScanning, true,                       \
          "Enables the parallelization of remembered set scanning "         \
          "during evacuation pauses")                                       \
                                                                            \
  product(uintx, G1ConcRefinementThreads, 0,                                \
          "If non-0 is the number of parallel rem set update threads, "     \
          "otherwise the value is determined ergonomically.")               \
                                                                            \
  develop(intx, G1CardCountCacheExpandThreshold, 16,                        \
          "Expand the card count cache if the number of collisions for "    \
          "a particular entry exceeds this value.")                         \
                                                                            \
  develop(bool, G1VerifyCTCleanup, false,                                   \
          "Verify card table cleanup.")                                     \
                                                                            \
  product(uintx, G1RSetScanBlockSize, 64,                                   \
          "Size of a work unit of cards claimed by a worker thread"         \
          "during RSet scanning.")                                          \
                                                                            \
  develop(uintx, G1SecondaryFreeListAppendLength, 5,                        \
          "The number of regions we will add to the secondary free list "   \
          "at every append operation")                                      \
                                                                            \
  develop(bool, G1ConcRegionFreeingVerbose, false,                          \
          "Enables verboseness during concurrent region freeing")           \
                                                                            \
  develop(bool, G1StressConcRegionFreeing, false,                           \
          "It stresses the concurrent region freeing operation")            \
                                                                            \
  develop(uintx, G1StressConcRegionFreeingDelayMillis, 0,                   \
          "Artificial delay during concurrent region freeing")              \
                                                                            \
  develop(bool, ReduceInitialCardMarksForG1, false,                         \
          "When ReduceInitialCardMarks is true, this flag setting "         \
          " controls whether G1 allows the RICM optimization")              \
                                                                            \
  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.")

G1_FLAGS(DECLARE_DEVELOPER_FLAG, DECLARE_PD_DEVELOPER_FLAG, DECLARE_PRODUCT_FLAG, DECLARE_PD_PRODUCT_FLAG, DECLARE_DIAGNOSTIC_FLAG, DECLARE_EXPERIMENTAL_FLAG, DECLARE_NOTPRODUCT_FLAG, DECLARE_MANAGEABLE_FLAG, DECLARE_PRODUCT_RW_FLAG)

#endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1_GLOBALS_HPP