Thu, 21 Aug 2014 16:44:41 +0200
8055098: WB API should be extended to provide information about size and age of object.
Summary: Extend the WhiteBox API to provide information about the size and age of objects. Further add a mechanism to trigger a young GC.
Reviewed-by: tschatzl, sjohanss
Contributed-by: Leonid Mesnik <leonid.mesnik@oracle.com>
1 /*
2 * Copyright (c) 2001, 2014, 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
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7 * published by the Free Software Foundation.
8 *
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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
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23 */
25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1_GLOBALS_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1_GLOBALS_HPP
28 #include "runtime/globals.hpp"
29 //
30 // Defines all globals flags used by the garbage-first compiler.
31 //
33 #define G1_FLAGS(develop, develop_pd, product, product_pd, diagnostic, experimental, notproduct, manageable, product_rw) \
34 \
35 product(uintx, G1ConfidencePercent, 50, \
36 "Confidence level for MMU/pause predictions") \
37 \
38 develop(intx, G1MarkingOverheadPercent, 0, \
39 "Overhead of concurrent marking") \
40 \
41 develop(intx, G1MarkingVerboseLevel, 0, \
42 "Level (0-4) of verboseness of the marking code") \
43 \
44 develop(bool, G1PrintReachableAtInitialMark, false, \
45 "Reachable object dump at the initial mark pause") \
46 \
47 develop(bool, G1VerifyDuringGCPrintReachable, false, \
48 "If conc mark verification fails, dump reachable objects") \
49 \
50 develop(ccstr, G1PrintReachableBaseFile, NULL, \
51 "The base file name for the reachable object dumps") \
52 \
53 develop(bool, G1TraceMarkStackOverflow, false, \
54 "If true, extra debugging code for CM restart for ovflw.") \
55 \
56 develop(bool, G1TraceHeapRegionRememberedSet, false, \
57 "Enables heap region remembered set debug logs") \
58 \
59 diagnostic(bool, G1SummarizeConcMark, false, \
60 "Summarize concurrent mark info") \
61 \
62 diagnostic(bool, G1SummarizeRSetStats, false, \
63 "Summarize remembered set processing info") \
64 \
65 diagnostic(intx, G1SummarizeRSetStatsPeriod, 0, \
66 "The period (in number of GCs) at which we will generate " \
67 "update buffer processing info " \
68 "(0 means do not periodically generate this info); " \
69 "it also requires -XX:+G1SummarizeRSetStats") \
70 \
71 diagnostic(bool, G1TraceConcRefinement, false, \
72 "Trace G1 concurrent refinement") \
73 \
74 experimental(bool, G1TraceStringSymbolTableScrubbing, false, \
75 "Trace information string and symbol table scrubbing.") \
76 \
77 product(double, G1ConcMarkStepDurationMillis, 10.0, \
78 "Target duration of individual concurrent marking steps " \
79 "in milliseconds.") \
80 \
81 product(intx, G1RefProcDrainInterval, 10, \
82 "The number of discovered reference objects to process before " \
83 "draining concurrent marking work queues.") \
84 \
85 experimental(bool, G1UseConcMarkReferenceProcessing, true, \
86 "If true, enable reference discovery during concurrent " \
87 "marking and reference processing at the end of remark.") \
88 \
89 product(intx, G1SATBBufferSize, 1*K, \
90 "Number of entries in an SATB log buffer.") \
91 \
92 develop(intx, G1SATBProcessCompletedThreshold, 20, \
93 "Number of completed buffers that triggers log processing.") \
94 \
95 product(uintx, G1SATBBufferEnqueueingThresholdPercent, 60, \
96 "Before enqueueing them, each mutator thread tries to do some " \
97 "filtering on the SATB buffers it generates. If post-filtering " \
98 "the percentage of retained entries is over this threshold " \
99 "the buffer will be enqueued for processing. A value of 0 " \
100 "specifies that mutator threads should not do such filtering.") \
101 \
102 develop(bool, G1SATBPrintStubs, false, \
103 "If true, print generated stubs for the SATB barrier") \
104 \
105 experimental(intx, G1ExpandByPercentOfAvailable, 20, \
106 "When expanding, % of uncommitted space to claim.") \
107 \
108 develop(bool, G1RSBarrierRegionFilter, true, \
109 "If true, generate region filtering code in RS barrier") \
110 \
111 develop(bool, G1DeferredRSUpdate, true, \
112 "If true, use deferred RS updates") \
113 \
114 develop(bool, G1RSLogCheckCardTable, false, \
115 "If true, verify that no dirty cards remain after RS log " \
116 "processing.") \
117 \
118 diagnostic(bool, G1PrintRegionLivenessInfo, false, \
119 "Prints the liveness information for all regions in the heap " \
120 "at the end of a marking cycle.") \
121 \
122 product(intx, G1UpdateBufferSize, 256, \
123 "Size of an update buffer") \
124 \
125 product(intx, G1ConcRefinementYellowZone, 0, \
126 "Number of enqueued update buffers that will " \
127 "trigger concurrent processing. Will be selected ergonomically " \
128 "by default.") \
129 \
130 product(intx, G1ConcRefinementRedZone, 0, \
131 "Maximum number of enqueued update buffers before mutator " \
132 "threads start processing new ones instead of enqueueing them. " \
133 "Will be selected ergonomically by default. Zero will disable " \
134 "concurrent processing.") \
135 \
136 product(intx, G1ConcRefinementGreenZone, 0, \
137 "The number of update buffers that are left in the queue by the " \
138 "concurrent processing threads. Will be selected ergonomically " \
139 "by default.") \
140 \
141 product(intx, G1ConcRefinementServiceIntervalMillis, 300, \
142 "The last concurrent refinement thread wakes up every " \
143 "specified number of milliseconds to do miscellaneous work.") \
144 \
145 product(intx, G1ConcRefinementThresholdStep, 0, \
146 "Each time the rset update queue increases by this amount " \
147 "activate the next refinement thread if available. " \
148 "Will be selected ergonomically by default.") \
149 \
150 product(intx, G1RSetUpdatingPauseTimePercent, 10, \
151 "A target percentage of time that is allowed to be spend on " \
152 "process RS update buffers during the collection pause.") \
153 \
154 product(bool, G1UseAdaptiveConcRefinement, true, \
155 "Select green, yellow and red zones adaptively to meet the " \
156 "the pause requirements.") \
157 \
158 product(uintx, G1ConcRSLogCacheSize, 10, \
159 "Log base 2 of the length of conc RS hot-card cache.") \
160 \
161 product(uintx, G1ConcRSHotCardLimit, 4, \
162 "The threshold that defines (>=) a hot card.") \
163 \
164 develop(intx, G1RSetRegionEntriesBase, 256, \
165 "Max number of regions in a fine-grain table per MB.") \
166 \
167 product(intx, G1RSetRegionEntries, 0, \
168 "Max number of regions for which we keep bitmaps." \
169 "Will be set ergonomically by default") \
170 \
171 develop(intx, G1RSetSparseRegionEntriesBase, 4, \
172 "Max number of entries per region in a sparse table " \
173 "per MB.") \
174 \
175 product(intx, G1RSetSparseRegionEntries, 0, \
176 "Max number of entries per region in a sparse table." \
177 "Will be set ergonomically by default.") \
178 \
179 develop(bool, G1RecordHRRSOops, false, \
180 "When true, record recent calls to rem set operations.") \
181 \
182 develop(bool, G1RecordHRRSEvents, false, \
183 "When true, record recent calls to rem set operations.") \
184 \
185 develop(intx, G1MaxVerifyFailures, -1, \
186 "The maximum number of verification failrues to print. " \
187 "-1 means print all.") \
188 \
189 develop(bool, G1ScrubRemSets, true, \
190 "When true, do RS scrubbing after cleanup.") \
191 \
192 develop(bool, G1RSScrubVerbose, false, \
193 "When true, do RS scrubbing with verbose output.") \
194 \
195 develop(bool, G1YoungSurvRateVerbose, false, \
196 "print out the survival rate of young regions according to age.") \
197 \
198 develop(intx, G1YoungSurvRateNumRegionsSummary, 0, \
199 "the number of regions for which we'll print a surv rate " \
200 "summary.") \
201 \
202 product(uintx, G1ReservePercent, 10, \
203 "It determines the minimum reserve we should have in the heap " \
204 "to minimize the probability of promotion failure.") \
205 \
206 diagnostic(bool, G1PrintHeapRegions, false, \
207 "If set G1 will print information on which regions are being " \
208 "allocated and which are reclaimed.") \
209 \
210 develop(bool, G1HRRSUseSparseTable, true, \
211 "When true, use sparse table to save space.") \
212 \
213 develop(bool, G1HRRSFlushLogBuffersOnVerify, false, \
214 "Forces flushing of log buffers before verification.") \
215 \
216 develop(bool, G1FailOnFPError, false, \
217 "When set, G1 will fail when it encounters an FP 'error', " \
218 "so as to allow debugging") \
219 \
220 product(uintx, G1HeapRegionSize, 0, \
221 "Size of the G1 regions.") \
222 \
223 experimental(bool, G1UseParallelRSetUpdating, true, \
224 "Enables the parallelization of remembered set updating " \
225 "during evacuation pauses") \
226 \
227 experimental(bool, G1UseParallelRSetScanning, true, \
228 "Enables the parallelization of remembered set scanning " \
229 "during evacuation pauses") \
230 \
231 product(uintx, G1ConcRefinementThreads, 0, \
232 "If non-0 is the number of parallel rem set update threads, " \
233 "otherwise the value is determined ergonomically.") \
234 \
235 develop(bool, G1VerifyCTCleanup, false, \
236 "Verify card table cleanup.") \
237 \
238 product(uintx, G1RSetScanBlockSize, 64, \
239 "Size of a work unit of cards claimed by a worker thread" \
240 "during RSet scanning.") \
241 \
242 develop(uintx, G1SecondaryFreeListAppendLength, 5, \
243 "The number of regions we will add to the secondary free list " \
244 "at every append operation") \
245 \
246 develop(bool, G1ConcRegionFreeingVerbose, false, \
247 "Enables verboseness during concurrent region freeing") \
248 \
249 develop(bool, G1StressConcRegionFreeing, false, \
250 "It stresses the concurrent region freeing operation") \
251 \
252 develop(uintx, G1StressConcRegionFreeingDelayMillis, 0, \
253 "Artificial delay during concurrent region freeing") \
254 \
255 develop(uintx, G1DummyRegionsPerGC, 0, \
256 "The number of dummy regions G1 will allocate at the end of " \
257 "each evacuation pause in order to artificially fill up the " \
258 "heap and stress the marking implementation.") \
259 \
260 develop(bool, G1ExitOnExpansionFailure, false, \
261 "Raise a fatal VM exit out of memory failure in the event " \
262 " that heap expansion fails due to running out of swap.") \
263 \
264 develop(uintx, G1ConcMarkForceOverflow, 0, \
265 "The number of times we'll force an overflow during " \
266 "concurrent marking") \
267 \
268 experimental(uintx, G1NewSizePercent, 5, \
269 "Percentage (0-100) of the heap size to use as default " \
270 "minimum young gen size.") \
271 \
272 experimental(uintx, G1MaxNewSizePercent, 60, \
273 "Percentage (0-100) of the heap size to use as default " \
274 " maximum young gen size.") \
275 \
276 experimental(uintx, G1MixedGCLiveThresholdPercent, 65, \
277 "Threshold for regions to be considered for inclusion in the " \
278 "collection set of mixed GCs. " \
279 "Regions with live bytes exceeding this will not be collected.") \
280 \
281 product(uintx, G1HeapWastePercent, 10, \
282 "Amount of space, expressed as a percentage of the heap size, " \
283 "that G1 is willing not to collect to avoid expensive GCs.") \
284 \
285 product(uintx, G1MixedGCCountTarget, 8, \
286 "The target number of mixed GCs after a marking cycle.") \
287 \
288 experimental(uintx, G1CodeRootsChunkCacheKeepPercent, 10, \
289 "The amount of code root chunks that should be kept at most " \
290 "as percentage of already allocated.") \
291 \
292 experimental(bool, G1ReclaimDeadHumongousObjectsAtYoungGC, true, \
293 "Try to reclaim dead large objects at every young GC.") \
294 \
295 experimental(bool, G1TraceReclaimDeadHumongousObjectsAtYoungGC, false, \
296 "Print some information about large object liveness " \
297 "at every young GC.") \
298 \
299 experimental(uintx, G1OldCSetRegionThresholdPercent, 10, \
300 "An upper bound for the number of old CSet regions expressed " \
301 "as a percentage of the heap size.") \
302 \
303 experimental(ccstr, G1LogLevel, NULL, \
304 "Log level for G1 logging: fine, finer, finest") \
305 \
306 notproduct(bool, G1EvacuationFailureALot, false, \
307 "Force use of evacuation failure handling during certain " \
308 "evacuation pauses") \
309 \
310 develop(uintx, G1EvacuationFailureALotCount, 1000, \
311 "Number of successful evacuations between evacuation failures " \
312 "occurring at object copying") \
313 \
314 develop(uintx, G1EvacuationFailureALotInterval, 5, \
315 "Total collections between forced triggering of evacuation " \
316 "failures") \
317 \
318 develop(bool, G1EvacuationFailureALotDuringConcMark, true, \
319 "Force use of evacuation failure handling during evacuation " \
320 "pauses when marking is in progress") \
321 \
322 develop(bool, G1EvacuationFailureALotDuringInitialMark, true, \
323 "Force use of evacuation failure handling during initial mark " \
324 "evacuation pauses") \
325 \
326 develop(bool, G1EvacuationFailureALotDuringYoungGC, true, \
327 "Force use of evacuation failure handling during young " \
328 "evacuation pauses") \
329 \
330 develop(bool, G1EvacuationFailureALotDuringMixedGC, true, \
331 "Force use of evacuation failure handling during mixed " \
332 "evacuation pauses") \
333 \
334 diagnostic(bool, G1VerifyRSetsDuringFullGC, false, \
335 "If true, perform verification of each heap region's " \
336 "remembered set when verifying the heap during a full GC.") \
337 \
338 diagnostic(bool, G1VerifyHeapRegionCodeRoots, false, \
339 "Verify the code root lists attached to each heap region.") \
340 \
341 develop(bool, G1VerifyBitmaps, false, \
342 "Verifies the consistency of the marking bitmaps")
344 G1_FLAGS(DECLARE_DEVELOPER_FLAG, DECLARE_PD_DEVELOPER_FLAG, DECLARE_PRODUCT_FLAG, DECLARE_PD_PRODUCT_FLAG, DECLARE_DIAGNOSTIC_FLAG, DECLARE_EXPERIMENTAL_FLAG, DECLARE_NOTPRODUCT_FLAG, DECLARE_MANAGEABLE_FLAG, DECLARE_PRODUCT_RW_FLAG)
346 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1_GLOBALS_HPP