1 /*
   2  * Copyright (c) 2001, 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_GC_G1_G1_GLOBALS_HPP
  26 #define SHARE_VM_GC_G1_G1_GLOBALS_HPP
  27 
  28 #include "runtime/globals.hpp"
  29 #include <float.h> // for DBL_MAX
  30 //
  31 // Defines all globals flags used by the garbage-first compiler.
  32 //
  33 
  34 #define G1_FLAGS(develop, develop_pd, product, product_pd, diagnostic, experimental, notproduct, manageable, product_rw, range, constraint) \
  35                                                                             \
  36   product(bool, G1UseAdaptiveIHOP, false,                                   \
  37           "Adaptively adjust InitiatingHeapOccupancyPercent from the "      \
  38           "initial value.")                                                 \
  39                                                                             \
  40   experimental(size_t, G1AdaptiveIHOPNumInitialSamples, 3,                  \
  41           "How many completed time periods from initial mark to first "     \
  42           "mixed gc are required to use the input values for prediction "   \
  43           "of the optimal occupancy to start marking.")                     \
  44           range(1, max_intx)                                                \
  45                                                                             \
  46   product(uintx, G1ConfidencePercent, 50,                                   \
  47           "Confidence level for MMU/pause predictions")                     \
  48           range(0, 100)                                                     \
  49                                                                             \
  50   develop(intx, G1MarkingOverheadPercent, 0,                                \
  51           "Overhead of concurrent marking")                                 \
  52           range(0, 100)                                                     \
  53                                                                             \
  54   develop(intx, G1MarkingVerboseLevel, 0,                                   \
  55           "Level (0-4) of verboseness of the marking code")                 \
  56           range(0, 4)                                                       \
  57                                                                             \
  58   develop(bool, G1TraceMarkStackOverflow, false,                            \
  59           "If true, extra debugging code for CM restart for ovflw.")        \
  60                                                                             \
  61   diagnostic(bool, G1SummarizeConcMark, false,                              \
  62           "Summarize concurrent mark info")                                 \
  63                                                                             \
  64   diagnostic(bool, G1SummarizeRSetStats, false,                             \
  65           "Summarize remembered set processing info")                       \
  66                                                                             \
  67   diagnostic(intx, G1SummarizeRSetStatsPeriod, 0,                           \
  68           "The period (in number of GCs) at which we will generate "        \
  69           "update buffer processing info "                                  \
  70           "(0 means do not periodically generate this info); "              \
  71           "it also requires -XX:+G1SummarizeRSetStats")                     \
  72           range(0, max_intx)                                                \
  73                                                                             \
  74   diagnostic(bool, G1TraceConcRefinement, false,                            \
  75           "Trace G1 concurrent refinement")                                 \
  76                                                                             \
  77   experimental(bool, G1TraceStringSymbolTableScrubbing, false,              \
  78           "Trace information string and symbol table scrubbing.")           \
  79                                                                             \
  80   product(double, G1ConcMarkStepDurationMillis, 10.0,                       \
  81           "Target duration of individual concurrent marking steps "         \
  82           "in milliseconds.")                                               \
  83           range(1.0, DBL_MAX)                                               \
  84                                                                             \
  85   product(intx, G1RefProcDrainInterval, 10,                                 \
  86           "The number of discovered reference objects to process before "   \
  87           "draining concurrent marking work queues.")                       \
  88           range(1, max_intx)                                                \
  89                                                                             \
  90   experimental(bool, G1UseConcMarkReferenceProcessing, true,                \
  91           "If true, enable reference discovery during concurrent "          \
  92           "marking and reference processing at the end of remark.")         \
  93                                                                             \
  94   experimental(double, G1LastPLABAverageOccupancy, 50.0,                    \
  95                "The expected average occupancy of the last PLAB in "        \
  96                "percent.")                                                  \
  97                range(0.001, 100.0)                                          \
  98                                                                             \
  99   product(size_t, G1SATBBufferSize, 1*K,                                    \
 100           "Number of entries in an SATB log buffer.")                       \
 101           range(1, max_uintx)                                               \
 102                                                                             \
 103   develop(intx, G1SATBProcessCompletedThreshold, 20,                        \
 104           "Number of completed buffers that triggers log processing.")      \
 105           range(0, max_jint)                                                \
 106                                                                             \
 107   product(uintx, G1SATBBufferEnqueueingThresholdPercent, 60,                \
 108           "Before enqueueing them, each mutator thread tries to do some "   \
 109           "filtering on the SATB buffers it generates. If post-filtering "  \
 110           "the percentage of retained entries is over this threshold "      \
 111           "the buffer will be enqueued for processing. A value of 0 "       \
 112           "specifies that mutator threads should not do such filtering.")   \
 113           range(0, 100)                                                     \
 114                                                                             \
 115   experimental(intx, G1ExpandByPercentOfAvailable, 20,                      \
 116           "When expanding, % of uncommitted space to claim.")               \
 117           range(0, 100)                                                     \
 118                                                                             \
 119   develop(bool, G1RSBarrierRegionFilter, true,                              \
 120           "If true, generate region filtering code in RS barrier")          \
 121                                                                             \
 122   diagnostic(bool, G1PrintRegionLivenessInfo, false,                        \
 123             "Prints the liveness information for all regions in the heap "  \
 124             "at the end of a marking cycle.")                               \
 125                                                                             \
 126   product(size_t, G1UpdateBufferSize, 256,                                  \
 127           "Size of an update buffer")                                       \
 128           range(1, NOT_LP64(32*M) LP64_ONLY(1*G))                           \
 129                                                                             \
 130   product(intx, G1ConcRefinementYellowZone, 0,                              \
 131           "Number of enqueued update buffers that will "                    \
 132           "trigger concurrent processing. Will be selected ergonomically "  \
 133           "by default.")                                                    \
 134           range(0, max_intx)                                                \
 135                                                                             \
 136   product(intx, G1ConcRefinementRedZone, 0,                                 \
 137           "Maximum number of enqueued update buffers before mutator "       \
 138           "threads start processing new ones instead of enqueueing them. "  \
 139           "Will be selected ergonomically by default. Zero will disable "   \
 140           "concurrent processing.")                                         \
 141           range(0, max_intx)                                                \
 142                                                                             \
 143   product(intx, G1ConcRefinementGreenZone, 0,                               \
 144           "The number of update buffers that are left in the queue by the " \
 145           "concurrent processing threads. Will be selected ergonomically "  \
 146           "by default.")                                                    \
 147           range(0, max_intx)                                                \
 148                                                                             \
 149   product(intx, G1ConcRefinementServiceIntervalMillis, 300,                 \
 150           "The last concurrent refinement thread wakes up every "           \
 151           "specified number of milliseconds to do miscellaneous work.")     \
 152           range(0, max_jint)                                                \
 153                                                                             \
 154   product(intx, G1ConcRefinementThresholdStep, 0,                           \
 155           "Each time the rset update queue increases by this amount "       \
 156           "activate the next refinement thread if available. "              \
 157           "Will be selected ergonomically by default.")                     \
 158                                                                             \
 159   product(intx, G1RSetUpdatingPauseTimePercent, 10,                         \
 160           "A target percentage of time that is allowed to be spend on "     \
 161           "process RS update buffers during the collection pause.")         \
 162           range(0, 100)                                                     \
 163                                                                             \
 164   product(bool, G1UseAdaptiveConcRefinement, true,                          \
 165           "Select green, yellow and red zones adaptively to meet the "      \
 166           "the pause requirements.")                                        \
 167                                                                             \
 168   product(size_t, G1ConcRSLogCacheSize, 10,                                 \
 169           "Log base 2 of the length of conc RS hot-card cache.")            \
 170           range(0, 27)                                                      \
 171                                                                             \
 172   product(uintx, G1ConcRSHotCardLimit, 4,                                   \
 173           "The threshold that defines (>=) a hot card.")                    \
 174           range(0, max_jubyte)                                              \
 175                                                                             \
 176   develop(intx, G1RSetRegionEntriesBase, 256,                               \
 177           "Max number of regions in a fine-grain table per MB.")            \
 178           range(1, max_jint/wordSize)                                       \
 179                                                                             \
 180   product(intx, G1RSetRegionEntries, 0,                                     \
 181           "Max number of regions for which we keep bitmaps."                \
 182           "Will be set ergonomically by default")                           \
 183           range(0, max_jint/wordSize)                                       \
 184           constraint(G1RSetRegionEntriesConstraintFunc,AfterErgo)           \
 185                                                                             \
 186   develop(intx, G1RSetSparseRegionEntriesBase, 4,                           \
 187           "Max number of entries per region in a sparse table "             \
 188           "per MB.")                                                        \
 189           range(1, max_jint/wordSize)                                       \
 190                                                                             \
 191   product(intx, G1RSetSparseRegionEntries, 0,                               \
 192           "Max number of entries per region in a sparse table."             \
 193           "Will be set ergonomically by default.")                          \
 194           range(0, max_jint/wordSize)                                       \
 195           constraint(G1RSetSparseRegionEntriesConstraintFunc,AfterErgo)     \
 196                                                                             \
 197   develop(intx, G1MaxVerifyFailures, -1,                                    \
 198           "The maximum number of verification failures to print.  "         \
 199           "-1 means print all.")                                            \
 200           range(-1, max_jint)                                               \
 201                                                                             \
 202   develop(bool, G1ScrubRemSets, true,                                       \
 203           "When true, do RS scrubbing after cleanup.")                      \
 204                                                                             \
 205   develop(bool, G1RSScrubVerbose, false,                                    \
 206           "When true, do RS scrubbing with verbose output.")                \
 207                                                                             \
 208   develop(bool, G1YoungSurvRateVerbose, false,                              \
 209           "print out the survival rate of young regions according to age.") \
 210                                                                             \
 211   develop(intx, G1YoungSurvRateNumRegionsSummary, 0,                        \
 212           "the number of regions for which we'll print a surv rate "        \
 213           "summary.")                                                       \
 214           range(0, max_intx)                                                \
 215           constraint(G1YoungSurvRateNumRegionsSummaryConstraintFunc,AfterErgo)\
 216                                                                             \
 217   product(uintx, G1ReservePercent, 10,                                      \
 218           "It determines the minimum reserve we should have in the heap "   \
 219           "to minimize the probability of promotion failure.")              \
 220           range(0, 50)                                                      \
 221                                                                             \
 222   diagnostic(bool, G1PrintHeapRegions, false,                               \
 223           "If set G1 will print information on which regions are being "    \
 224           "allocated and which are reclaimed.")                             \
 225                                                                             \
 226   develop(bool, G1HRRSUseSparseTable, true,                                 \
 227           "When true, use sparse table to save space.")                     \
 228                                                                             \
 229   develop(bool, G1HRRSFlushLogBuffersOnVerify, false,                       \
 230           "Forces flushing of log buffers before verification.")            \
 231                                                                             \
 232   product(size_t, G1HeapRegionSize, 0,                                      \
 233           "Size of the G1 regions.")                                        \
 234           range(0, 32*M)                                                    \
 235           constraint(G1HeapRegionSizeConstraintFunc,AfterMemoryInit)        \
 236                                                                             \
 237   product(uintx, G1ConcRefinementThreads, 0,                                \
 238           "If non-0 is the number of parallel rem set update threads, "     \
 239           "otherwise the value is determined ergonomically.")               \
 240           range(0, (max_jint-1)/wordSize)                                   \
 241                                                                             \
 242   develop(bool, G1VerifyCTCleanup, false,                                   \
 243           "Verify card table cleanup.")                                     \
 244                                                                             \
 245   product(size_t, G1RSetScanBlockSize, 64,                                  \
 246           "Size of a work unit of cards claimed by a worker thread"         \
 247           "during RSet scanning.")                                          \
 248           range(1, max_uintx)                                               \
 249                                                                             \
 250   develop(uintx, G1SecondaryFreeListAppendLength, 5,                        \
 251           "The number of regions we will add to the secondary free list "   \
 252           "at every append operation")                                      \
 253                                                                             \
 254   develop(bool, G1ConcRegionFreeingVerbose, false,                          \
 255           "Enables verboseness during concurrent region freeing")           \
 256                                                                             \
 257   develop(bool, G1StressConcRegionFreeing, false,                           \
 258           "It stresses the concurrent region freeing operation")            \
 259                                                                             \
 260   develop(uintx, G1StressConcRegionFreeingDelayMillis, 0,                   \
 261           "Artificial delay during concurrent region freeing")              \
 262                                                                             \
 263   develop(uintx, G1DummyRegionsPerGC, 0,                                    \
 264           "The number of dummy regions G1 will allocate at the end of "     \
 265           "each evacuation pause in order to artificially fill up the "     \
 266           "heap and stress the marking implementation.")                    \
 267                                                                             \
 268   develop(bool, G1ExitOnExpansionFailure, false,                            \
 269           "Raise a fatal VM exit out of memory failure in the event "       \
 270           " that heap expansion fails due to running out of swap.")         \
 271                                                                             \
 272   develop(uintx, G1ConcMarkForceOverflow, 0,                                \
 273           "The number of times we'll force an overflow during "             \
 274           "concurrent marking")                                             \
 275                                                                             \
 276   experimental(uintx, G1MaxNewSizePercent, 60,                              \
 277           "Percentage (0-100) of the heap size to use as default "          \
 278           " maximum young gen size.")                                       \
 279           range(0, 100)                                                     \
 280           constraint(G1MaxNewSizePercentConstraintFunc,AfterErgo)           \
 281                                                                             \
 282   experimental(uintx, G1NewSizePercent, 5,                                  \
 283           "Percentage (0-100) of the heap size to use as default "          \
 284           "minimum young gen size.")                                        \
 285           range(0, 100)                                                     \
 286           constraint(G1NewSizePercentConstraintFunc,AfterErgo)              \
 287                                                                             \
 288   experimental(uintx, G1MixedGCLiveThresholdPercent, 85,                    \
 289           "Threshold for regions to be considered for inclusion in the "    \
 290           "collection set of mixed GCs. "                                   \
 291           "Regions with live bytes exceeding this will not be collected.")  \
 292           range(0, 100)                                                     \
 293                                                                             \
 294   product(uintx, G1HeapWastePercent, 5,                                     \
 295           "Amount of space, expressed as a percentage of the heap size, "   \
 296           "that G1 is willing not to collect to avoid expensive GCs.")      \
 297           range(0, 100)                                                     \
 298                                                                             \
 299   product(uintx, G1MixedGCCountTarget, 8,                                   \
 300           "The target number of mixed GCs after a marking cycle.")          \
 301                                                                             \
 302   experimental(bool, G1EagerReclaimHumongousObjects, true,                  \
 303           "Try to reclaim dead large objects at every young GC.")           \
 304                                                                             \
 305   experimental(bool, G1EagerReclaimHumongousObjectsWithStaleRefs, true,     \
 306           "Try to reclaim dead large objects that have a few stale "        \
 307           "references at every young GC.")                                  \
 308                                                                             \
 309   experimental(bool, G1TraceEagerReclaimHumongousObjects, false,            \
 310           "Print some information about large object liveness "             \
 311           "at every young GC.")                                             \
 312                                                                             \
 313   experimental(bool, G1RetainAllocRegionsDuringGC, true,                    \
 314           "Try to retain and reuse allocation regions with some space left "\
 315           "during GC.")                                                     \
 316                                                                             \
 317   experimental(uintx, G1OldCSetRegionThresholdPercent, 10,                  \
 318           "An upper bound for the number of old CSet regions expressed "    \
 319           "as a percentage of the heap size.")                              \
 320           range(0, 100)                                                     \
 321                                                                             \
 322   experimental(ccstr, G1LogLevel, NULL,                                     \
 323           "Log level for G1 logging: fine, finer, finest")                  \
 324                                                                             \
 325   notproduct(bool, G1EvacuationFailureALot, false,                          \
 326           "Force use of evacuation failure handling during certain "        \
 327           "evacuation pauses")                                              \
 328                                                                             \
 329   develop(uintx, G1EvacuationFailureALotCount, 1000,                        \
 330           "Number of successful evacuations between evacuation failures "   \
 331           "occurring at object copying")                                    \
 332                                                                             \
 333   develop(uintx, G1EvacuationFailureALotInterval, 5,                        \
 334           "Total collections between forced triggering of evacuation "      \
 335           "failures")                                                       \
 336                                                                             \
 337   develop(bool, G1EvacuationFailureALotDuringConcMark, true,                \
 338           "Force use of evacuation failure handling during evacuation "     \
 339           "pauses when marking is in progress")                             \
 340                                                                             \
 341   develop(bool, G1EvacuationFailureALotDuringInitialMark, true,             \
 342           "Force use of evacuation failure handling during initial mark "   \
 343           "evacuation pauses")                                              \
 344                                                                             \
 345   develop(bool, G1EvacuationFailureALotDuringYoungGC, true,                 \
 346           "Force use of evacuation failure handling during young "          \
 347           "evacuation pauses")                                              \
 348                                                                             \
 349   develop(bool, G1EvacuationFailureALotDuringMixedGC, true,                 \
 350           "Force use of evacuation failure handling during mixed "          \
 351           "evacuation pauses")                                              \
 352                                                                             \
 353   diagnostic(bool, G1VerifyRSetsDuringFullGC, false,                        \
 354           "If true, perform verification of each heap region's "            \
 355           "remembered set when verifying the heap during a full GC.")       \
 356                                                                             \
 357   diagnostic(bool, G1VerifyHeapRegionCodeRoots, false,                      \
 358           "Verify the code root lists attached to each heap region.")       \
 359                                                                             \
 360   develop(bool, G1VerifyBitmaps, false,                                     \
 361           "Verifies the consistency of the marking bitmaps")
 362 
 363 G1_FLAGS(DECLARE_DEVELOPER_FLAG, \
 364          DECLARE_PD_DEVELOPER_FLAG, \
 365          DECLARE_PRODUCT_FLAG, \
 366          DECLARE_PD_PRODUCT_FLAG, \
 367          DECLARE_DIAGNOSTIC_FLAG, \
 368          DECLARE_EXPERIMENTAL_FLAG, \
 369          DECLARE_NOTPRODUCT_FLAG, \
 370          DECLARE_MANAGEABLE_FLAG, \
 371          DECLARE_PRODUCT_RW_FLAG, \
 372          IGNORE_RANGE, \
 373          IGNORE_CONSTRAINT)
 374 
 375 #endif // SHARE_VM_GC_G1_G1_GLOBALS_HPP