1 /* 2 * Copyright (c) 2016, Red Hat, Inc. and/or its affiliates. 3 * 4 * This code is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License version 2 only, as 6 * published by the Free Software Foundation. 7 * 8 * This code is distributed in the hope that it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 11 * version 2 for more details (a copy is included in the LICENSE file that 12 * accompanied this code). 13 * 14 * You should have received a copy of the GNU General Public License version 15 * 2 along with this work; if not, write to the Free Software Foundation, 16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 17 * 18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 19 * or visit www.oracle.com if you need additional information or have any 20 * questions. 21 * 22 */ 23 24 #ifndef SHARE_VM_GC_SHENANDOAH_SHENANDOAH_GLOBALS_HPP 25 #define SHARE_VM_GC_SHENANDOAH_SHENANDOAH_GLOBALS_HPP 26 27 #include "runtime/globals.hpp" 28 29 #define SHENANDOAH_FLAGS(develop, \ 30 develop_pd, \ 31 product, \ 32 product_pd, \ 33 diagnostic, \ 34 experimental, \ 35 notproduct, \ 36 manageable, \ 37 product_rw, \ 38 range, \ 39 constraint, \ 40 writeable) \ 41 \ 42 product(bool, UseShenandoahGC, false, \ 43 "Use the Shenandoah garbage collector") \ 44 \ 45 product(bool, ShenandoahOptimizeFinals, true, \ 46 "Optimize barriers on final and stable fields/arrays. " \ 47 "Turn it off for maximum compatibility with reflection or JNI " \ 48 "code that manipulates final fields." \ 49 "Defaults to true. ") \ 50 \ 51 product(size_t, ShenandoahHeapRegionSize, 0, \ 52 "Size of the Shenandoah regions. " \ 53 "Determined automatically by default.") \ 54 \ 55 experimental(size_t, ShenandoahMinRegionSize, 256 * K, \ 56 "Minimum heap region size. ") \ 57 \ 58 experimental(size_t, ShenandoahMaxRegionSize, 32 * M, \ 59 "Maximum heap region size. ") \ 60 \ 61 experimental(size_t, ShenandoahTargetNumRegions, 2048, \ 62 "Target number of regions. We try to get around that many " \ 63 "regions, based on ShenandoahMinRegionSize and " \ 64 "ShenandoahMaxRegionSizeSize. ") \ 65 \ 66 product(bool, UseShenandoahMatrix, false, \ 67 "Keep a connection matrix and use this to drive collection sets") \ 68 \ 69 product(bool, PrintShenandoahMatrix, false, \ 70 "Print connection matrix after marking") \ 71 \ 72 product(bool, VerifyShenandoahMatrix, false, \ 73 "Verify connection matrix after marking") \ 74 \ 75 product(ccstr, ShenandoahGCHeuristics, "adaptive", \ 76 "The heuristics to use in Shenandoah GC. Possible values: " \ 77 "dynamic, adaptive, aggressive." \ 78 "Defaults to adaptive") \ 79 \ 80 product(uintx, ShenandoahRefProcFrequency, 5, \ 81 "How often should (weak, soft, etc) references be processed. " \ 82 "References get processed at every Nth GC cycle. " \ 83 "Set to 0 to disable reference processing. " \ 84 "Defaults to process references every 5 cycles.") \ 85 \ 86 product(uintx, ShenandoahUnloadClassesFrequency, 5, \ 87 "How often should classes get unloaded. " \ 88 "Class unloading is performed at every Nth GC cycle. " \ 89 "Set to 0 to disable concurrent class unloading. " \ 90 "Defaults to unload classes every 5 cycles.") \ 91 \ 92 experimental(uintx, ShenandoahFullGCThreshold, 3, \ 93 "How many cycles in a row to do degenerated marking on " \ 94 "cancelled GC before triggering a full-gc" \ 95 "Defaults to 3") \ 96 writeable(Always) \ 97 \ 98 product_rw(uintx, ShenandoahGarbageThreshold, 60, \ 99 "Sets the percentage of garbage a region need to contain before " \ 100 "it can be marked for collection. Applies to " \ 101 "Shenandoah GC dynamic Heuristic mode only (ignored otherwise). " \ 102 "Defaults to 60%.") \ 103 range(0,100) \ 104 \ 105 product_rw(uintx, ShenandoahFreeThreshold, 10, \ 106 "Set the percentage of free heap at which a GC cycle is started. " \ 107 "Applies to Shenandoah GC dynamic Heuristic mode only " \ 108 "(ignored otherwise). Defaults to 10%.") \ 109 range(0,100) \ 110 \ 111 product_rw(uintx, ShenandoahCSetThreshold, 40, \ 112 "Set the approximate target percentage of the heap for the" \ 113 "collection set. Defaults to 40%.") \ 114 range(0,100) \ 115 \ 116 product_rw(uintx, ShenandoahAllocationThreshold, 0, \ 117 "Set percentage of memory allocated since last GC cycle before " \ 118 "a new GC cycle is started. " \ 119 "Applies to Shenandoah GC dynamic Heuristic mode only " \ 120 "(ignored otherwise). Defauls to 0%.") \ 121 range(0,100) \ 122 \ 123 experimental(uintx, ShenandoahInitFreeThreshold, 10, \ 124 "Initial remaininig free threshold for adaptive heuristics") \ 125 range(0,100) \ 126 \ 127 experimental(uintx, ShenandoahMinFreeThreshold, 3, \ 128 "Minimum remaininig free threshold for adaptive heuristics") \ 129 range(0,100) \ 130 \ 131 experimental(uintx, ShenandoahMaxFreeThreshold, 70, \ 132 "Maximum remaininig free threshold for adaptive heuristics") \ 133 range(0,100) \ 134 \ 135 experimental(uintx, ShenandoahHappyCyclesThreshold, 5, \ 136 "How many successful marking cycles before improving free " \ 137 "threshold for adaptive heuristics") \ 138 \ 139 experimental(uint, ShenandoahMarkLoopStride, 1000, \ 140 "How many items are processed during one marking step") \ 141 \ 142 experimental(bool, ShenandoahConcurrentCodeRoots, true, \ 143 "Scan code roots concurrently, instead of during a pause") \ 144 \ 145 experimental(bool, ShenandoahNoBarriersForConst, true, \ 146 "Constant oops don't need barriers") \ 147 \ 148 experimental(bool, ShenandoahDontIncreaseWBFreq, true, \ 149 "Common 2 WriteBarriers or WriteBarrier and a ReadBarrier only " \ 150 "if the resulting WriteBarrier isn't executed more frequently") \ 151 \ 152 experimental(bool, ShenandoahNoLivenessFullGC, true, \ 153 "Skip liveness counting for mark during full GC.") \ 154 \ 155 experimental(bool, ShenandoahWriteBarrierToIR, true, \ 156 "Convert write barrier to IR instead of using assembly blob") \ 157 \ 158 experimental(bool, ShenandoahWriteBarrierCsetTestInIR, true, \ 159 "Perform cset test in IR rather than in the stub") \ 160 \ 161 experimental(bool, ShenandoahLoopOptsAfterExpansion, true, \ 162 "Attempt more loop opts after write barrier expansion") \ 163 \ 164 experimental(bool, UseShenandoahOWST, true, \ 165 "Use Shenandoah work stealing termination protocol") \ 166 \ 167 experimental(size_t, ShenandoahSATBBufferSize, 1 * K, \ 168 "Number of entries in an SATB log buffer.") \ 169 range(1, max_uintx) \ 170 \ 171 experimental(int, ShenandoahRegionSamplingRate, 40, \ 172 "Sampling rate for heap region sampling. " \ 173 "Number of milliseconds between samples") \ 174 writeable(Always) \ 175 \ 176 experimental(bool, ShenandoahRegionSampling, false, \ 177 "Turns on heap region sampling via JVMStat") \ 178 writeable(Always) \ 179 \ 180 experimental(bool, ShenandoahReduceStoreValBarrier, false, \ 181 "If true, only execute storeval barrier when updating " \ 182 "references.") \ 183 \ 184 diagnostic(bool, ShenandoahWriteBarrier, true, \ 185 "Turn on/off write barriers in Shenandoah") \ 186 \ 187 diagnostic(bool, ShenandoahReadBarrier, true, \ 188 "Turn on/off read barriers in Shenandoah") \ 189 \ 190 diagnostic(bool, ShenandoahCASBarrier, true, \ 191 "Turn on/off CAS barriers in Shenandoah") \ 192 \ 193 diagnostic(bool, ShenandoahAcmpBarrier, true, \ 194 "Turn on/off acmp barriers in Shenandoah") \ 195 \ 196 diagnostic(bool, ShenandoahCloneBarrier, true, \ 197 "Turn on/off clone barriers in Shenandoah") \ 198 \ 199 diagnostic(bool, ShenandoahStoreCheck, false, \ 200 "Emit additional code that checks objects are written to only" \ 201 " in to-space") \ 202 \ 203 develop(bool, ShenandoahDumpHeapBeforeConcurrentMark, false, \ 204 "Dump the ShenanodahHeap Before Each ConcurrentMark") \ 205 \ 206 develop(bool, ShenandoahDumpHeapAfterConcurrentMark, false, \ 207 "Dump the ShenanodahHeap After Each Concurrent Mark") \ 208 \ 209 develop(bool, ShenandoahVerifyWritesToFromSpace, false, \ 210 "Use Memory Protection to signal illegal writes to from space") \ 211 \ 212 develop(bool, ShenandoahVerifyReadsToFromSpace, false, \ 213 "Use Memory Protection to signal illegal reads to from space") \ 214 \ 215 develop(bool, ShenandoahVerify, false, \ 216 "Verify the Shenandoah garbage collector") \ 217 \ 218 develop(bool, VerifyStrictOopOperations, false, \ 219 "Verify that == and != are not used on oops. Only in fastdebug") \ 220 \ 221 develop(bool, ShenandoahVerifyOptoBarriers, false, \ 222 "Verify no missing barriers in c2") \ 223 \ 224 product(bool, ShenandoahAlwaysPreTouch, false, \ 225 "Pre-touch heap memory, overrides global AlwaysPreTouch") \ 226 \ 227 experimental(intx, ShenandoahMarkScanPrefetch, 32, \ 228 "How many objects to prefetch ahead when traversing mark bitmaps." \ 229 "Set to 0 to disable prefetching.") \ 230 range(0, 1024) \ 231 \ 232 experimental(intx, ShenandoahFullGCTries, 3, \ 233 "How many times to try to do Full GC on allocation failure." \ 234 "Set to 0 to never try, and fail instead.") \ 235 range(0, 16) \ 236 237 238 SHENANDOAH_FLAGS(DECLARE_DEVELOPER_FLAG, \ 239 DECLARE_PD_DEVELOPER_FLAG, \ 240 DECLARE_PRODUCT_FLAG, \ 241 DECLARE_PD_PRODUCT_FLAG, \ 242 DECLARE_DIAGNOSTIC_FLAG, \ 243 DECLARE_EXPERIMENTAL_FLAG, \ 244 DECLARE_NOTPRODUCT_FLAG, \ 245 DECLARE_MANAGEABLE_FLAG, \ 246 DECLARE_PRODUCT_RW_FLAG, \ 247 IGNORE_RANGE, \ 248 IGNORE_CONSTRAINT, \ 249 IGNORE_WRITEABLE) 250 251 #endif // SHARE_VM_GC_SHENANDOAH_SHENANDOAH_GLOBALS_HPP