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