1 /*
   2  * Copyright (c) 2001, 2018, 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 <float.h> // for DBL_MAX
  29 //
  30 // Defines all globals flags used by the garbage-first compiler.
  31 //
  32 
  33 #define GC_G1_FLAGS(develop,                                                \
  34                     develop_pd,                                             \
  35                     product,                                                \
  36                     product_pd,                                             \
  37                     diagnostic,                                             \
  38                     diagnostic_pd,                                          \
  39                     experimental,                                           \
  40                     notproduct,                                             \
  41                     manageable,                                             \
  42                     product_rw,                                             \
  43                     lp64_product,                                           \
  44                     range,                                                  \
  45                     constraint,                                             \
  46                     writeable)                                              \
  47                                                                             \
  48   product(bool, G1UseAdaptiveIHOP, true,                                    \
  49           "Adaptively adjust the initiating heap occupancy from the "       \
  50           "initial value of InitiatingHeapOccupancyPercent. The policy "    \
  51           "attempts to start marking in time based on application "         \
  52           "behavior.")                                                      \
  53                                                                             \
  54   experimental(size_t, G1AdaptiveIHOPNumInitialSamples, 3,                  \
  55           "How many completed time periods from initial mark to first "     \
  56           "mixed gc are required to use the input values for prediction "   \
  57           "of the optimal occupancy to start marking.")                     \
  58           range(1, max_intx)                                                \
  59                                                                             \
  60   product(uintx, G1ConfidencePercent, 50,                                   \
  61           "Confidence level for MMU/pause predictions")                     \
  62           range(0, 100)                                                     \
  63                                                                             \
  64   diagnostic(intx, G1SummarizeRSetStatsPeriod, 0,                           \
  65           "The period (in number of GCs) at which we will generate "        \
  66           "update buffer processing info "                                  \
  67           "(0 means do not periodically generate this info); "              \
  68           "it also requires that logging is enabled on the trace"           \
  69           "level for gc+remset")                                            \
  70           range(0, max_intx)                                                \
  71                                                                             \
  72   product(double, G1ConcMarkStepDurationMillis, 10.0,                       \
  73           "Target duration of individual concurrent marking steps "         \
  74           "in milliseconds.")                                               \
  75           range(1.0, DBL_MAX)                                               \
  76                                                                             \
  77   product(uint, G1RefProcDrainInterval, 1000,                               \
  78           "The number of discovered reference objects to process before "   \
  79           "draining concurrent marking work queues.")                       \
  80           range(1, INT_MAX)                                                 \
  81                                                                             \
  82   experimental(bool, G1UseReferencePrecleaning, true,                       \
  83                "Concurrently preclean java.lang.ref.references instances "  \
  84                "before the Remark pause.")                                  \
  85                                                                             \
  86   experimental(double, G1LastPLABAverageOccupancy, 50.0,                    \
  87                "The expected average occupancy of the last PLAB in "        \
  88                "percent.")                                                  \
  89                range(0.001, 100.0)                                          \
  90                                                                             \
  91   product(size_t, G1SATBBufferSize, 1*K,                                    \
  92           "Number of entries in an SATB log buffer.")                       \
  93           range(1, max_uintx)                                               \
  94                                                                             \
  95   develop(intx, G1SATBProcessCompletedThreshold, 20,                        \
  96           "Number of completed buffers that triggers log processing.")      \
  97           range(0, max_jint)                                                \
  98                                                                             \
  99   product(uintx, G1SATBBufferEnqueueingThresholdPercent, 60,                \
 100           "Before enqueueing them, each mutator thread tries to do some "   \
 101           "filtering on the SATB buffers it generates. If post-filtering "  \
 102           "the percentage of retained entries is over this threshold "      \
 103           "the buffer will be enqueued for processing. A value of 0 "       \
 104           "specifies that mutator threads should not do such filtering.")   \
 105           range(0, 100)                                                     \
 106                                                                             \
 107   experimental(intx, G1ExpandByPercentOfAvailable, 20,                      \
 108           "When expanding, % of uncommitted space to claim.")               \
 109           range(0, 100)                                                     \
 110                                                                             \
 111   develop(bool, G1RSBarrierRegionFilter, true,                              \
 112           "If true, generate region filtering code in RS barrier")          \
 113                                                                             \
 114   product(size_t, G1UpdateBufferSize, 256,                                  \
 115           "Size of an update buffer")                                       \
 116           range(1, NOT_LP64(32*M) LP64_ONLY(1*G))                           \
 117                                                                             \
 118   product(size_t, G1ConcRefinementYellowZone, 0,                            \
 119           "Number of enqueued update buffers that will "                    \
 120           "trigger concurrent processing. Will be selected ergonomically "  \
 121           "by default.")                                                    \
 122           range(0, max_intx)                                                \
 123                                                                             \
 124   product(size_t, G1ConcRefinementRedZone, 0,                               \
 125           "Maximum number of enqueued update buffers before mutator "       \
 126           "threads start processing new ones instead of enqueueing them. "  \
 127           "Will be selected ergonomically by default.")                     \
 128           range(0, max_intx)                                                \
 129                                                                             \
 130   product(size_t, G1ConcRefinementGreenZone, 0,                             \
 131           "The number of update buffers that are left in the queue by the " \
 132           "concurrent processing threads. Will be selected ergonomically "  \
 133           "by default.")                                                    \
 134           range(0, max_intx)                                                \
 135                                                                             \
 136   product(uintx, G1ConcRefinementServiceIntervalMillis, 300,                \
 137           "The last concurrent refinement thread wakes up every "           \
 138           "specified number of milliseconds to do miscellaneous work.")     \
 139           range(0, max_jint)                                                \
 140                                                                             \
 141   product(size_t, G1ConcRefinementThresholdStep, 2,                         \
 142           "Each time the rset update queue increases by this amount "       \
 143           "activate the next refinement thread if available. "              \
 144           "The actual step size will be selected ergonomically by "         \
 145           "default, with this value used to determine a lower bound.")      \
 146           range(1, SIZE_MAX)                                                \
 147                                                                             \
 148   product(intx, G1RSetUpdatingPauseTimePercent, 10,                         \
 149           "A target percentage of time that is allowed to be spend on "     \
 150           "process RS update buffers during the collection pause.")         \
 151           range(0, 100)                                                     \
 152                                                                             \
 153   product(bool, G1UseAdaptiveConcRefinement, true,                          \
 154           "Select green, yellow and red zones adaptively to meet the "      \
 155           "the pause requirements.")                                        \
 156                                                                             \
 157   product(size_t, G1ConcRSLogCacheSize, 10,                                 \
 158           "Log base 2 of the length of conc RS hot-card cache.")            \
 159           range(0, 27)                                                      \
 160                                                                             \
 161   product(uintx, G1ConcRSHotCardLimit, 4,                                   \
 162           "The threshold that defines (>=) a hot card.")                    \
 163           range(0, max_jubyte)                                              \
 164                                                                             \
 165   develop(intx, G1RSetRegionEntriesBase, 256,                               \
 166           "Max number of regions in a fine-grain table per MB.")            \
 167           range(1, max_jint/wordSize)                                       \
 168                                                                             \
 169   product(intx, G1RSetRegionEntries, 0,                                     \
 170           "Max number of regions for which we keep bitmaps."                \
 171           "Will be set ergonomically by default")                           \
 172           range(0, max_jint/wordSize)                                       \
 173           constraint(G1RSetRegionEntriesConstraintFunc,AfterErgo)           \
 174                                                                             \
 175   develop(intx, G1RSetSparseRegionEntriesBase, 4,                           \
 176           "Max number of entries per region in a sparse table "             \
 177           "per MB.")                                                        \
 178           range(1, max_jint/wordSize)                                       \
 179                                                                             \
 180   product(intx, G1RSetSparseRegionEntries, 0,                               \
 181           "Max number of entries per region in a sparse table."             \
 182           "Will be set ergonomically by default.")                          \
 183           range(0, max_jint/wordSize)                                       \
 184           constraint(G1RSetSparseRegionEntriesConstraintFunc,AfterErgo)     \
 185                                                                             \
 186   develop(intx, G1MaxVerifyFailures, -1,                                    \
 187           "The maximum number of verification failures to print.  "         \
 188           "-1 means print all.")                                            \
 189           range(-1, max_jint)                                               \
 190                                                                             \
 191   product(uintx, G1ReservePercent, 10,                                      \
 192           "It determines the minimum reserve we should have in the heap "   \
 193           "to minimize the probability of promotion failure.")              \
 194           range(0, 50)                                                      \
 195                                                                             \
 196   develop(bool, G1HRRSUseSparseTable, true,                                 \
 197           "When true, use sparse table to save space.")                     \
 198                                                                             \
 199   product(size_t, G1HeapRegionSize, 0,                                      \
 200           "Size of the G1 regions.")                                        \
 201           range(0, 32*M)                                                    \
 202           constraint(G1HeapRegionSizeConstraintFunc,AfterMemoryInit)        \
 203                                                                             \
 204   product(uint, G1ConcRefinementThreads, 0,                                 \
 205           "The number of parallel rem set update threads. "                 \
 206           "Will be set ergonomically by default.")                          \
 207           range(0, (max_jint-1)/wordSize)                                   \
 208                                                                             \
 209   develop(bool, G1VerifyCTCleanup, false,                                   \
 210           "Verify card table cleanup.")                                     \
 211                                                                             \
 212   product(size_t, G1RSetScanBlockSize, 64,                                  \
 213           "Size of a work unit of cards claimed by a worker thread"         \
 214           "during RSet scanning.")                                          \
 215           range(1, max_uintx)                                               \
 216                                                                             \
 217   develop(uintx, G1DummyRegionsPerGC, 0,                                    \
 218           "The number of dummy regions G1 will allocate at the end of "     \
 219           "each evacuation pause in order to artificially fill up the "     \
 220           "heap and stress the marking implementation.")                    \
 221                                                                             \
 222   develop(bool, G1ExitOnExpansionFailure, false,                            \
 223           "Raise a fatal VM exit out of memory failure in the event "       \
 224           " that heap expansion fails due to running out of swap.")         \
 225                                                                             \
 226   experimental(uintx, G1MaxNewSizePercent, 60,                              \
 227           "Percentage (0-100) of the heap size to use as default "          \
 228           " maximum young gen size.")                                       \
 229           range(0, 100)                                                     \
 230           constraint(G1MaxNewSizePercentConstraintFunc,AfterErgo)           \
 231                                                                             \
 232   experimental(uintx, G1NewSizePercent, 5,                                  \
 233           "Percentage (0-100) of the heap size to use as default "          \
 234           "minimum young gen size.")                                        \
 235           range(0, 100)                                                     \
 236           constraint(G1NewSizePercentConstraintFunc,AfterErgo)              \
 237                                                                             \
 238   experimental(uintx, G1MixedGCLiveThresholdPercent, 85,                    \
 239           "Threshold for regions to be considered for inclusion in the "    \
 240           "collection set of mixed GCs. "                                   \
 241           "Regions with live bytes exceeding this will not be collected.")  \
 242           range(0, 100)                                                     \
 243                                                                             \
 244   product(uintx, G1HeapWastePercent, 5,                                     \
 245           "Amount of space, expressed as a percentage of the heap size, "   \
 246           "that G1 is willing not to collect to avoid expensive GCs.")      \
 247           range(0, 100)                                                     \
 248                                                                             \
 249   product(uintx, G1MixedGCCountTarget, 8,                                   \
 250           "The target number of mixed GCs after a marking cycle.")          \
 251           range(0, max_uintx)                                               \
 252                                                                             \
 253   experimental(bool, G1PretouchAuxiliaryMemory, false,                      \
 254           "Pre-touch large auxiliary data structures used by the GC.")      \
 255                                                                             \
 256   experimental(bool, G1EagerReclaimHumongousObjects, true,                  \
 257           "Try to reclaim dead large objects at every young GC.")           \
 258                                                                             \
 259   experimental(bool, G1EagerReclaimHumongousObjectsWithStaleRefs, true,     \
 260           "Try to reclaim dead large objects that have a few stale "        \
 261           "references at every young GC.")                                  \
 262                                                                             \
 263   experimental(size_t, G1RebuildRemSetChunkSize, 256 * K,                   \
 264           "Chunk size used for rebuilding the remembered set.")             \
 265           range(4 * K, 32 * M)                                              \
 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 #endif // SHARE_VM_GC_G1_G1_GLOBALS_HPP