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