Mercurial > hg > truffle
annotate src/share/vm/gc_implementation/parallelScavenge/psAdaptiveSizePolicy.cpp @ 4937:73df3733f2eb
7129284: +DoEscapeAnalysis regression w/ early build of 7u4 (HotSpot 23) on Linux
Summary: Removed code which tried to create edges from fields of destination objects of arraycopy to fields of source objects. Added 30 sec time limit for EA graph construction.
Reviewed-by: never
author | kvn |
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date | Fri, 10 Feb 2012 12:53:43 -0800 |
parents | f95d63e2154a |
children | da91efe96a93 |
rev | line source |
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0 | 1 /* |
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2 * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved. |
0 | 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 * | |
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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20 * or visit www.oracle.com if you need additional information or have any |
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21 * questions. |
0 | 22 * |
23 */ | |
24 | |
1972 | 25 #include "precompiled.hpp" |
26 #include "gc_implementation/parallelScavenge/generationSizer.hpp" | |
27 #include "gc_implementation/parallelScavenge/psAdaptiveSizePolicy.hpp" | |
28 #include "gc_implementation/parallelScavenge/psGCAdaptivePolicyCounters.hpp" | |
29 #include "gc_implementation/parallelScavenge/psScavenge.hpp" | |
30 #include "gc_implementation/shared/gcPolicyCounters.hpp" | |
31 #include "gc_interface/gcCause.hpp" | |
32 #include "memory/collectorPolicy.hpp" | |
33 #include "runtime/timer.hpp" | |
34 #include "utilities/top.hpp" | |
0 | 35 |
36 #include <math.h> | |
37 | |
38 PSAdaptiveSizePolicy::PSAdaptiveSizePolicy(size_t init_eden_size, | |
39 size_t init_promo_size, | |
40 size_t init_survivor_size, | |
41 size_t intra_generation_alignment, | |
42 double gc_pause_goal_sec, | |
43 double gc_minor_pause_goal_sec, | |
44 uint gc_cost_ratio) : | |
45 AdaptiveSizePolicy(init_eden_size, | |
46 init_promo_size, | |
47 init_survivor_size, | |
48 gc_pause_goal_sec, | |
49 gc_cost_ratio), | |
50 _collection_cost_margin_fraction(AdaptiveSizePolicyCollectionCostMargin/ | |
51 100.0), | |
52 _intra_generation_alignment(intra_generation_alignment), | |
53 _live_at_last_full_gc(init_promo_size), | |
54 _gc_minor_pause_goal_sec(gc_minor_pause_goal_sec), | |
55 _latest_major_mutator_interval_seconds(0), | |
56 _young_gen_change_for_major_pause_count(0) | |
57 { | |
58 // Sizing policy statistics | |
59 _avg_major_pause = | |
60 new AdaptivePaddedAverage(AdaptiveTimeWeight, PausePadding); | |
61 _avg_minor_interval = new AdaptiveWeightedAverage(AdaptiveTimeWeight); | |
62 _avg_major_interval = new AdaptiveWeightedAverage(AdaptiveTimeWeight); | |
63 | |
64 _avg_base_footprint = new AdaptiveWeightedAverage(AdaptiveSizePolicyWeight); | |
65 _major_pause_old_estimator = | |
66 new LinearLeastSquareFit(AdaptiveSizePolicyWeight); | |
67 _major_pause_young_estimator = | |
68 new LinearLeastSquareFit(AdaptiveSizePolicyWeight); | |
69 _major_collection_estimator = | |
70 new LinearLeastSquareFit(AdaptiveSizePolicyWeight); | |
71 | |
72 _young_gen_size_increment_supplement = YoungGenerationSizeSupplement; | |
73 _old_gen_size_increment_supplement = TenuredGenerationSizeSupplement; | |
74 | |
75 // Start the timers | |
76 _major_timer.start(); | |
77 | |
78 _old_gen_policy_is_ready = false; | |
79 } | |
80 | |
81 void PSAdaptiveSizePolicy::major_collection_begin() { | |
82 // Update the interval time | |
83 _major_timer.stop(); | |
84 // Save most recent collection time | |
85 _latest_major_mutator_interval_seconds = _major_timer.seconds(); | |
86 _major_timer.reset(); | |
87 _major_timer.start(); | |
88 } | |
89 | |
90 void PSAdaptiveSizePolicy::update_minor_pause_old_estimator( | |
91 double minor_pause_in_ms) { | |
92 double promo_size_in_mbytes = ((double)_promo_size)/((double)M); | |
93 _minor_pause_old_estimator->update(promo_size_in_mbytes, | |
94 minor_pause_in_ms); | |
95 } | |
96 | |
97 void PSAdaptiveSizePolicy::major_collection_end(size_t amount_live, | |
98 GCCause::Cause gc_cause) { | |
99 // Update the pause time. | |
100 _major_timer.stop(); | |
101 | |
102 if (gc_cause != GCCause::_java_lang_system_gc || | |
103 UseAdaptiveSizePolicyWithSystemGC) { | |
104 double major_pause_in_seconds = _major_timer.seconds(); | |
105 double major_pause_in_ms = major_pause_in_seconds * MILLIUNITS; | |
106 | |
107 // Sample for performance counter | |
108 _avg_major_pause->sample(major_pause_in_seconds); | |
109 | |
110 // Cost of collection (unit-less) | |
111 double collection_cost = 0.0; | |
112 if ((_latest_major_mutator_interval_seconds > 0.0) && | |
113 (major_pause_in_seconds > 0.0)) { | |
114 double interval_in_seconds = | |
115 _latest_major_mutator_interval_seconds + major_pause_in_seconds; | |
116 collection_cost = | |
117 major_pause_in_seconds / interval_in_seconds; | |
118 avg_major_gc_cost()->sample(collection_cost); | |
119 | |
120 // Sample for performance counter | |
121 _avg_major_interval->sample(interval_in_seconds); | |
122 } | |
123 | |
124 // Calculate variables used to estimate pause time vs. gen sizes | |
125 double eden_size_in_mbytes = ((double)_eden_size)/((double)M); | |
126 double promo_size_in_mbytes = ((double)_promo_size)/((double)M); | |
127 _major_pause_old_estimator->update(promo_size_in_mbytes, | |
128 major_pause_in_ms); | |
129 _major_pause_young_estimator->update(eden_size_in_mbytes, | |
130 major_pause_in_ms); | |
131 | |
132 if (PrintAdaptiveSizePolicy && Verbose) { | |
133 gclog_or_tty->print("psAdaptiveSizePolicy::major_collection_end: " | |
134 "major gc cost: %f average: %f", collection_cost, | |
135 avg_major_gc_cost()->average()); | |
136 gclog_or_tty->print_cr(" major pause: %f major period %f", | |
137 major_pause_in_ms, | |
138 _latest_major_mutator_interval_seconds * MILLIUNITS); | |
139 } | |
140 | |
141 // Calculate variable used to estimate collection cost vs. gen sizes | |
142 assert(collection_cost >= 0.0, "Expected to be non-negative"); | |
143 _major_collection_estimator->update(promo_size_in_mbytes, | |
144 collection_cost); | |
145 } | |
146 | |
147 // Update the amount live at the end of a full GC | |
148 _live_at_last_full_gc = amount_live; | |
149 | |
150 // The policy does not have enough data until at least some major collections | |
151 // have been done. | |
152 if (_avg_major_pause->count() >= AdaptiveSizePolicyReadyThreshold) { | |
153 _old_gen_policy_is_ready = true; | |
154 } | |
155 | |
156 // Interval times use this timer to measure the interval that | |
157 // the mutator runs. Reset after the GC pause has been measured. | |
158 _major_timer.reset(); | |
159 _major_timer.start(); | |
160 } | |
161 | |
162 // If the remaining free space in the old generation is less that | |
163 // that expected to be needed by the next collection, do a full | |
164 // collection now. | |
165 bool PSAdaptiveSizePolicy::should_full_GC(size_t old_free_in_bytes) { | |
166 | |
167 // A similar test is done in the scavenge's should_attempt_scavenge(). If | |
168 // this is changed, decide if that test should also be changed. | |
169 bool result = padded_average_promoted_in_bytes() > (float) old_free_in_bytes; | |
170 if (PrintGCDetails && Verbose) { | |
171 if (result) { | |
172 gclog_or_tty->print(" full after scavenge: "); | |
173 } else { | |
174 gclog_or_tty->print(" no full after scavenge: "); | |
175 } | |
176 gclog_or_tty->print_cr(" average_promoted " SIZE_FORMAT | |
177 " padded_average_promoted " SIZE_FORMAT | |
178 " free in old gen " SIZE_FORMAT, | |
179 (size_t) average_promoted_in_bytes(), | |
180 (size_t) padded_average_promoted_in_bytes(), | |
181 old_free_in_bytes); | |
182 } | |
183 return result; | |
184 } | |
185 | |
186 void PSAdaptiveSizePolicy::clear_generation_free_space_flags() { | |
187 | |
188 AdaptiveSizePolicy::clear_generation_free_space_flags(); | |
189 | |
190 set_change_old_gen_for_min_pauses(0); | |
191 | |
192 set_change_young_gen_for_maj_pauses(0); | |
193 } | |
194 | |
195 // If this is not a full GC, only test and modify the young generation. | |
196 | |
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197 void PSAdaptiveSizePolicy::compute_generation_free_space( |
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198 size_t young_live, |
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199 size_t eden_live, |
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200 size_t old_live, |
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201 size_t perm_live, |
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202 size_t cur_eden, |
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203 size_t max_old_gen_size, |
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204 size_t max_eden_size, |
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205 bool is_full_gc, |
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206 GCCause::Cause gc_cause, |
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207 CollectorPolicy* collector_policy) { |
0 | 208 |
209 // Update statistics | |
210 // Time statistics are updated as we go, update footprint stats here | |
211 _avg_base_footprint->sample(BaseFootPrintEstimate + perm_live); | |
212 avg_young_live()->sample(young_live); | |
213 avg_eden_live()->sample(eden_live); | |
214 if (is_full_gc) { | |
215 // old_live is only accurate after a full gc | |
216 avg_old_live()->sample(old_live); | |
217 } | |
218 | |
219 // This code used to return if the policy was not ready , i.e., | |
220 // policy_is_ready() returning false. The intent was that | |
221 // decisions below needed major collection times and so could | |
222 // not be made before two major collections. A consequence was | |
223 // adjustments to the young generation were not done until after | |
224 // two major collections even if the minor collections times | |
225 // exceeded the requested goals. Now let the young generation | |
226 // adjust for the minor collection times. Major collection times | |
227 // will be zero for the first collection and will naturally be | |
228 // ignored. Tenured generation adjustments are only made at the | |
229 // full collections so until the second major collection has | |
230 // been reached, no tenured generation adjustments will be made. | |
231 | |
232 // Until we know better, desired promotion size uses the last calculation | |
233 size_t desired_promo_size = _promo_size; | |
234 | |
235 // Start eden at the current value. The desired value that is stored | |
236 // in _eden_size is not bounded by constraints of the heap and can | |
237 // run away. | |
238 // | |
239 // As expected setting desired_eden_size to the current | |
240 // value of desired_eden_size as a starting point | |
241 // caused desired_eden_size to grow way too large and caused | |
242 // an overflow down stream. It may have improved performance in | |
243 // some case but is dangerous. | |
244 size_t desired_eden_size = cur_eden; | |
245 | |
246 #ifdef ASSERT | |
247 size_t original_promo_size = desired_promo_size; | |
248 size_t original_eden_size = desired_eden_size; | |
249 #endif | |
250 | |
251 // Cache some values. There's a bit of work getting these, so | |
252 // we might save a little time. | |
253 const double major_cost = major_gc_cost(); | |
254 const double minor_cost = minor_gc_cost(); | |
255 | |
256 // Used for diagnostics | |
257 clear_generation_free_space_flags(); | |
258 | |
259 // Limits on our growth | |
260 size_t promo_limit = (size_t)(max_old_gen_size - avg_old_live()->average()); | |
261 | |
262 // This method sets the desired eden size. That plus the | |
263 // desired survivor space sizes sets the desired young generation | |
264 // size. This methods does not know what the desired survivor | |
265 // size is but expects that other policy will attempt to make | |
266 // the survivor sizes compatible with the live data in the | |
267 // young generation. This limit is an estimate of the space left | |
268 // in the young generation after the survivor spaces have been | |
269 // subtracted out. | |
270 size_t eden_limit = max_eden_size; | |
271 | |
272 // But don't force a promo size below the current promo size. Otherwise, | |
273 // the promo size will shrink for no good reason. | |
274 promo_limit = MAX2(promo_limit, _promo_size); | |
275 | |
276 const double gc_cost_limit = GCTimeLimit/100.0; | |
277 | |
278 // Which way should we go? | |
279 // if pause requirement is not met | |
280 // adjust size of any generation with average paus exceeding | |
281 // the pause limit. Adjust one pause at a time (the larger) | |
282 // and only make adjustments for the major pause at full collections. | |
283 // else if throughput requirement not met | |
284 // adjust the size of the generation with larger gc time. Only | |
285 // adjust one generation at a time. | |
286 // else | |
287 // adjust down the total heap size. Adjust down the larger of the | |
288 // generations. | |
289 | |
290 // Add some checks for a threshhold for a change. For example, | |
291 // a change less than the necessary alignment is probably not worth | |
292 // attempting. | |
293 | |
294 | |
295 if ((_avg_minor_pause->padded_average() > gc_pause_goal_sec()) || | |
296 (_avg_major_pause->padded_average() > gc_pause_goal_sec())) { | |
297 // | |
298 // Check pauses | |
299 // | |
300 // Make changes only to affect one of the pauses (the larger) | |
301 // at a time. | |
302 adjust_for_pause_time(is_full_gc, &desired_promo_size, &desired_eden_size); | |
303 | |
304 } else if (_avg_minor_pause->padded_average() > gc_minor_pause_goal_sec()) { | |
305 // Adjust only for the minor pause time goal | |
306 adjust_for_minor_pause_time(is_full_gc, &desired_promo_size, &desired_eden_size); | |
307 | |
308 } else if(adjusted_mutator_cost() < _throughput_goal) { | |
309 // This branch used to require that (mutator_cost() > 0.0 in 1.4.2. | |
310 // This sometimes resulted in skipping to the minimize footprint | |
311 // code. Change this to try and reduce GC time if mutator time is | |
312 // negative for whatever reason. Or for future consideration, | |
313 // bail out of the code if mutator time is negative. | |
314 // | |
315 // Throughput | |
316 // | |
317 assert(major_cost >= 0.0, "major cost is < 0.0"); | |
318 assert(minor_cost >= 0.0, "minor cost is < 0.0"); | |
319 // Try to reduce the GC times. | |
320 adjust_for_throughput(is_full_gc, &desired_promo_size, &desired_eden_size); | |
321 | |
322 } else { | |
323 | |
324 // Be conservative about reducing the footprint. | |
325 // Do a minimum number of major collections first. | |
326 // Have reasonable averages for major and minor collections costs. | |
327 if (UseAdaptiveSizePolicyFootprintGoal && | |
328 young_gen_policy_is_ready() && | |
329 avg_major_gc_cost()->average() >= 0.0 && | |
330 avg_minor_gc_cost()->average() >= 0.0) { | |
331 size_t desired_sum = desired_eden_size + desired_promo_size; | |
332 desired_eden_size = adjust_eden_for_footprint(desired_eden_size, | |
333 desired_sum); | |
334 if (is_full_gc) { | |
335 set_decide_at_full_gc(decide_at_full_gc_true); | |
336 desired_promo_size = adjust_promo_for_footprint(desired_promo_size, | |
337 desired_sum); | |
338 } | |
339 } | |
340 } | |
341 | |
342 // Note we make the same tests as in the code block below; the code | |
343 // seems a little easier to read with the printing in another block. | |
344 if (PrintAdaptiveSizePolicy) { | |
345 if (desired_promo_size > promo_limit) { | |
346 // "free_in_old_gen" was the original value for used for promo_limit | |
347 size_t free_in_old_gen = (size_t)(max_old_gen_size - avg_old_live()->average()); | |
348 gclog_or_tty->print_cr( | |
349 "PSAdaptiveSizePolicy::compute_generation_free_space limits:" | |
350 " desired_promo_size: " SIZE_FORMAT | |
351 " promo_limit: " SIZE_FORMAT | |
352 " free_in_old_gen: " SIZE_FORMAT | |
353 " max_old_gen_size: " SIZE_FORMAT | |
354 " avg_old_live: " SIZE_FORMAT, | |
355 desired_promo_size, promo_limit, free_in_old_gen, | |
356 max_old_gen_size, (size_t) avg_old_live()->average()); | |
357 } | |
358 if (desired_eden_size > eden_limit) { | |
359 gclog_or_tty->print_cr( | |
360 "AdaptiveSizePolicy::compute_generation_free_space limits:" | |
361 " desired_eden_size: " SIZE_FORMAT | |
362 " old_eden_size: " SIZE_FORMAT | |
363 " eden_limit: " SIZE_FORMAT | |
364 " cur_eden: " SIZE_FORMAT | |
365 " max_eden_size: " SIZE_FORMAT | |
366 " avg_young_live: " SIZE_FORMAT, | |
367 desired_eden_size, _eden_size, eden_limit, cur_eden, | |
368 max_eden_size, (size_t)avg_young_live()->average()); | |
369 } | |
370 if (gc_cost() > gc_cost_limit) { | |
371 gclog_or_tty->print_cr( | |
372 "AdaptiveSizePolicy::compute_generation_free_space: gc time limit" | |
373 " gc_cost: %f " | |
374 " GCTimeLimit: %d", | |
375 gc_cost(), GCTimeLimit); | |
376 } | |
377 } | |
378 | |
379 // Align everything and make a final limit check | |
380 const size_t alignment = _intra_generation_alignment; | |
381 desired_eden_size = align_size_up(desired_eden_size, alignment); | |
382 desired_eden_size = MAX2(desired_eden_size, alignment); | |
383 desired_promo_size = align_size_up(desired_promo_size, alignment); | |
384 desired_promo_size = MAX2(desired_promo_size, alignment); | |
385 | |
386 eden_limit = align_size_down(eden_limit, alignment); | |
387 promo_limit = align_size_down(promo_limit, alignment); | |
388 | |
389 // Is too much time being spent in GC? | |
390 // Is the heap trying to grow beyond it's limits? | |
391 | |
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392 const size_t free_in_old_gen = |
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393 (size_t)(max_old_gen_size - avg_old_live()->average()); |
0 | 394 if (desired_promo_size > free_in_old_gen && desired_eden_size > eden_limit) { |
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395 check_gc_overhead_limit(young_live, |
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396 eden_live, |
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397 max_old_gen_size, |
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398 max_eden_size, |
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399 is_full_gc, |
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400 gc_cause, |
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401 collector_policy); |
0 | 402 } |
403 | |
404 | |
405 // And one last limit check, now that we've aligned things. | |
406 if (desired_eden_size > eden_limit) { | |
407 // If the policy says to get a larger eden but | |
408 // is hitting the limit, don't decrease eden. | |
409 // This can lead to a general drifting down of the | |
410 // eden size. Let the tenuring calculation push more | |
411 // into the old gen. | |
412 desired_eden_size = MAX2(eden_limit, cur_eden); | |
413 } | |
414 desired_promo_size = MIN2(desired_promo_size, promo_limit); | |
415 | |
416 | |
417 if (PrintAdaptiveSizePolicy) { | |
418 // Timing stats | |
419 gclog_or_tty->print( | |
420 "PSAdaptiveSizePolicy::compute_generation_free_space: costs" | |
421 " minor_time: %f" | |
422 " major_cost: %f" | |
423 " mutator_cost: %f" | |
424 " throughput_goal: %f", | |
425 minor_gc_cost(), major_gc_cost(), mutator_cost(), | |
426 _throughput_goal); | |
427 | |
428 // We give more details if Verbose is set | |
429 if (Verbose) { | |
430 gclog_or_tty->print( " minor_pause: %f" | |
431 " major_pause: %f" | |
432 " minor_interval: %f" | |
433 " major_interval: %f" | |
434 " pause_goal: %f", | |
435 _avg_minor_pause->padded_average(), | |
436 _avg_major_pause->padded_average(), | |
437 _avg_minor_interval->average(), | |
438 _avg_major_interval->average(), | |
439 gc_pause_goal_sec()); | |
440 } | |
441 | |
442 // Footprint stats | |
443 gclog_or_tty->print( " live_space: " SIZE_FORMAT | |
444 " free_space: " SIZE_FORMAT, | |
445 live_space(), free_space()); | |
446 // More detail | |
447 if (Verbose) { | |
448 gclog_or_tty->print( " base_footprint: " SIZE_FORMAT | |
449 " avg_young_live: " SIZE_FORMAT | |
450 " avg_old_live: " SIZE_FORMAT, | |
451 (size_t)_avg_base_footprint->average(), | |
452 (size_t)avg_young_live()->average(), | |
453 (size_t)avg_old_live()->average()); | |
454 } | |
455 | |
456 // And finally, our old and new sizes. | |
457 gclog_or_tty->print(" old_promo_size: " SIZE_FORMAT | |
458 " old_eden_size: " SIZE_FORMAT | |
459 " desired_promo_size: " SIZE_FORMAT | |
460 " desired_eden_size: " SIZE_FORMAT, | |
461 _promo_size, _eden_size, | |
462 desired_promo_size, desired_eden_size); | |
463 gclog_or_tty->cr(); | |
464 } | |
465 | |
466 decay_supplemental_growth(is_full_gc); | |
467 | |
468 set_promo_size(desired_promo_size); | |
469 set_eden_size(desired_eden_size); | |
470 }; | |
471 | |
472 void PSAdaptiveSizePolicy::decay_supplemental_growth(bool is_full_gc) { | |
473 // Decay the supplemental increment? Decay the supplement growth | |
474 // factor even if it is not used. It is only meant to give a boost | |
475 // to the initial growth and if it is not used, then it was not | |
476 // needed. | |
477 if (is_full_gc) { | |
478 // Don't wait for the threshold value for the major collections. If | |
479 // here, the supplemental growth term was used and should decay. | |
480 if ((_avg_major_pause->count() % TenuredGenerationSizeSupplementDecay) | |
481 == 0) { | |
482 _old_gen_size_increment_supplement = | |
483 _old_gen_size_increment_supplement >> 1; | |
484 } | |
485 } else { | |
486 if ((_avg_minor_pause->count() >= AdaptiveSizePolicyReadyThreshold) && | |
487 (_avg_minor_pause->count() % YoungGenerationSizeSupplementDecay) == 0) { | |
488 _young_gen_size_increment_supplement = | |
489 _young_gen_size_increment_supplement >> 1; | |
490 } | |
491 } | |
492 } | |
493 | |
494 void PSAdaptiveSizePolicy::adjust_for_minor_pause_time(bool is_full_gc, | |
495 size_t* desired_promo_size_ptr, size_t* desired_eden_size_ptr) { | |
496 | |
497 // Adjust the young generation size to reduce pause time of | |
498 // of collections. | |
499 // | |
500 // The AdaptiveSizePolicyInitializingSteps test is not used | |
501 // here. It has not seemed to be needed but perhaps should | |
502 // be added for consistency. | |
503 if (minor_pause_young_estimator()->decrement_will_decrease()) { | |
504 // reduce eden size | |
505 set_change_young_gen_for_min_pauses( | |
506 decrease_young_gen_for_min_pauses_true); | |
507 *desired_eden_size_ptr = *desired_eden_size_ptr - | |
508 eden_decrement_aligned_down(*desired_eden_size_ptr); | |
509 } else { | |
510 // EXPERIMENTAL ADJUSTMENT | |
511 // Only record that the estimator indicated such an action. | |
512 // *desired_eden_size_ptr = *desired_eden_size_ptr + eden_heap_delta; | |
513 set_change_young_gen_for_min_pauses( | |
514 increase_young_gen_for_min_pauses_true); | |
515 } | |
516 if (PSAdjustTenuredGenForMinorPause) { | |
517 // If the desired eden size is as small as it will get, | |
518 // try to adjust the old gen size. | |
519 if (*desired_eden_size_ptr <= _intra_generation_alignment) { | |
520 // Vary the old gen size to reduce the young gen pause. This | |
521 // may not be a good idea. This is just a test. | |
522 if (minor_pause_old_estimator()->decrement_will_decrease()) { | |
523 set_change_old_gen_for_min_pauses( | |
524 decrease_old_gen_for_min_pauses_true); | |
525 *desired_promo_size_ptr = | |
526 _promo_size - promo_decrement_aligned_down(*desired_promo_size_ptr); | |
527 } else { | |
528 set_change_old_gen_for_min_pauses( | |
529 increase_old_gen_for_min_pauses_true); | |
530 size_t promo_heap_delta = | |
531 promo_increment_with_supplement_aligned_up(*desired_promo_size_ptr); | |
532 if ((*desired_promo_size_ptr + promo_heap_delta) > | |
533 *desired_promo_size_ptr) { | |
534 *desired_promo_size_ptr = | |
535 _promo_size + promo_heap_delta; | |
536 } | |
537 } | |
538 } | |
539 } | |
540 } | |
541 | |
542 void PSAdaptiveSizePolicy::adjust_for_pause_time(bool is_full_gc, | |
543 size_t* desired_promo_size_ptr, | |
544 size_t* desired_eden_size_ptr) { | |
545 | |
546 size_t promo_heap_delta = 0; | |
547 size_t eden_heap_delta = 0; | |
548 // Add some checks for a threshhold for a change. For example, | |
549 // a change less than the required alignment is probably not worth | |
550 // attempting. | |
551 if (is_full_gc) { | |
552 set_decide_at_full_gc(decide_at_full_gc_true); | |
553 } | |
554 | |
555 if (_avg_minor_pause->padded_average() > _avg_major_pause->padded_average()) { | |
556 adjust_for_minor_pause_time(is_full_gc, | |
557 desired_promo_size_ptr, | |
558 desired_eden_size_ptr); | |
559 // major pause adjustments | |
560 } else if (is_full_gc) { | |
561 // Adjust for the major pause time only at full gc's because the | |
562 // affects of a change can only be seen at full gc's. | |
563 | |
564 // Reduce old generation size to reduce pause? | |
565 if (major_pause_old_estimator()->decrement_will_decrease()) { | |
566 // reduce old generation size | |
567 set_change_old_gen_for_maj_pauses(decrease_old_gen_for_maj_pauses_true); | |
568 promo_heap_delta = promo_decrement_aligned_down(*desired_promo_size_ptr); | |
569 *desired_promo_size_ptr = _promo_size - promo_heap_delta; | |
570 } else { | |
571 // EXPERIMENTAL ADJUSTMENT | |
572 // Only record that the estimator indicated such an action. | |
573 // *desired_promo_size_ptr = _promo_size + | |
574 // promo_increment_aligned_up(*desired_promo_size_ptr); | |
575 set_change_old_gen_for_maj_pauses(increase_old_gen_for_maj_pauses_true); | |
576 } | |
577 if (PSAdjustYoungGenForMajorPause) { | |
578 // If the promo size is at the minimum (i.e., the old gen | |
579 // size will not actually decrease), consider changing the | |
580 // young gen size. | |
581 if (*desired_promo_size_ptr < _intra_generation_alignment) { | |
582 // If increasing the young generation will decrease the old gen | |
583 // pause, do it. | |
584 // During startup there is noise in the statistics for deciding | |
585 // on whether to increase or decrease the young gen size. For | |
586 // some number of iterations, just try to increase the young | |
587 // gen size if the major pause is too long to try and establish | |
588 // good statistics for later decisions. | |
589 if (major_pause_young_estimator()->increment_will_decrease() || | |
590 (_young_gen_change_for_major_pause_count | |
591 <= AdaptiveSizePolicyInitializingSteps)) { | |
592 set_change_young_gen_for_maj_pauses( | |
593 increase_young_gen_for_maj_pauses_true); | |
594 eden_heap_delta = eden_increment_aligned_up(*desired_eden_size_ptr); | |
595 *desired_eden_size_ptr = _eden_size + eden_heap_delta; | |
596 _young_gen_change_for_major_pause_count++; | |
597 } else { | |
598 // Record that decreasing the young gen size would decrease | |
599 // the major pause | |
600 set_change_young_gen_for_maj_pauses( | |
601 decrease_young_gen_for_maj_pauses_true); | |
602 eden_heap_delta = eden_decrement_aligned_down(*desired_eden_size_ptr); | |
603 *desired_eden_size_ptr = _eden_size - eden_heap_delta; | |
604 } | |
605 } | |
606 } | |
607 } | |
608 | |
609 if (PrintAdaptiveSizePolicy && Verbose) { | |
610 gclog_or_tty->print_cr( | |
611 "AdaptiveSizePolicy::compute_generation_free_space " | |
612 "adjusting gen sizes for major pause (avg %f goal %f). " | |
613 "desired_promo_size " SIZE_FORMAT "desired_eden_size " | |
614 SIZE_FORMAT | |
615 " promo delta " SIZE_FORMAT " eden delta " SIZE_FORMAT, | |
616 _avg_major_pause->average(), gc_pause_goal_sec(), | |
617 *desired_promo_size_ptr, *desired_eden_size_ptr, | |
618 promo_heap_delta, eden_heap_delta); | |
619 } | |
620 } | |
621 | |
622 void PSAdaptiveSizePolicy::adjust_for_throughput(bool is_full_gc, | |
623 size_t* desired_promo_size_ptr, | |
624 size_t* desired_eden_size_ptr) { | |
625 | |
626 // Add some checks for a threshhold for a change. For example, | |
627 // a change less than the required alignment is probably not worth | |
628 // attempting. | |
629 if (is_full_gc) { | |
630 set_decide_at_full_gc(decide_at_full_gc_true); | |
631 } | |
632 | |
633 if ((gc_cost() + mutator_cost()) == 0.0) { | |
634 return; | |
635 } | |
636 | |
637 if (PrintAdaptiveSizePolicy && Verbose) { | |
638 gclog_or_tty->print("\nPSAdaptiveSizePolicy::adjust_for_throughput(" | |
639 "is_full: %d, promo: " SIZE_FORMAT ", cur_eden: " SIZE_FORMAT "): ", | |
640 is_full_gc, *desired_promo_size_ptr, *desired_eden_size_ptr); | |
641 gclog_or_tty->print_cr("mutator_cost %f major_gc_cost %f " | |
642 "minor_gc_cost %f", mutator_cost(), major_gc_cost(), minor_gc_cost()); | |
643 } | |
644 | |
645 // Tenured generation | |
646 if (is_full_gc) { | |
647 | |
648 // Calculate the change to use for the tenured gen. | |
649 size_t scaled_promo_heap_delta = 0; | |
650 // Can the increment to the generation be scaled? | |
651 if (gc_cost() >= 0.0 && major_gc_cost() >= 0.0) { | |
652 size_t promo_heap_delta = | |
653 promo_increment_with_supplement_aligned_up(*desired_promo_size_ptr); | |
654 double scale_by_ratio = major_gc_cost() / gc_cost(); | |
655 scaled_promo_heap_delta = | |
656 (size_t) (scale_by_ratio * (double) promo_heap_delta); | |
657 if (PrintAdaptiveSizePolicy && Verbose) { | |
658 gclog_or_tty->print_cr( | |
659 "Scaled tenured increment: " SIZE_FORMAT " by %f down to " | |
660 SIZE_FORMAT, | |
661 promo_heap_delta, scale_by_ratio, scaled_promo_heap_delta); | |
662 } | |
663 } else if (major_gc_cost() >= 0.0) { | |
664 // Scaling is not going to work. If the major gc time is the | |
665 // larger, give it a full increment. | |
666 if (major_gc_cost() >= minor_gc_cost()) { | |
667 scaled_promo_heap_delta = | |
668 promo_increment_with_supplement_aligned_up(*desired_promo_size_ptr); | |
669 } | |
670 } else { | |
671 // Don't expect to get here but it's ok if it does | |
672 // in the product build since the delta will be 0 | |
673 // and nothing will change. | |
674 assert(false, "Unexpected value for gc costs"); | |
675 } | |
676 | |
677 switch (AdaptiveSizeThroughPutPolicy) { | |
678 case 1: | |
679 // Early in the run the statistics might not be good. Until | |
680 // a specific number of collections have been, use the heuristic | |
681 // that a larger generation size means lower collection costs. | |
682 if (major_collection_estimator()->increment_will_decrease() || | |
683 (_old_gen_change_for_major_throughput | |
684 <= AdaptiveSizePolicyInitializingSteps)) { | |
685 // Increase tenured generation size to reduce major collection cost | |
686 if ((*desired_promo_size_ptr + scaled_promo_heap_delta) > | |
687 *desired_promo_size_ptr) { | |
688 *desired_promo_size_ptr = _promo_size + scaled_promo_heap_delta; | |
689 } | |
690 set_change_old_gen_for_throughput( | |
691 increase_old_gen_for_throughput_true); | |
692 _old_gen_change_for_major_throughput++; | |
693 } else { | |
694 // EXPERIMENTAL ADJUSTMENT | |
695 // Record that decreasing the old gen size would decrease | |
696 // the major collection cost but don't do it. | |
697 // *desired_promo_size_ptr = _promo_size - | |
698 // promo_decrement_aligned_down(*desired_promo_size_ptr); | |
699 set_change_old_gen_for_throughput( | |
700 decrease_old_gen_for_throughput_true); | |
701 } | |
702 | |
703 break; | |
704 default: | |
705 // Simplest strategy | |
706 if ((*desired_promo_size_ptr + scaled_promo_heap_delta) > | |
707 *desired_promo_size_ptr) { | |
708 *desired_promo_size_ptr = *desired_promo_size_ptr + | |
709 scaled_promo_heap_delta; | |
710 } | |
711 set_change_old_gen_for_throughput( | |
712 increase_old_gen_for_throughput_true); | |
713 _old_gen_change_for_major_throughput++; | |
714 } | |
715 | |
716 if (PrintAdaptiveSizePolicy && Verbose) { | |
717 gclog_or_tty->print_cr( | |
718 "adjusting tenured gen for throughput (avg %f goal %f). " | |
719 "desired_promo_size " SIZE_FORMAT " promo_delta " SIZE_FORMAT , | |
720 mutator_cost(), _throughput_goal, | |
721 *desired_promo_size_ptr, scaled_promo_heap_delta); | |
722 } | |
723 } | |
724 | |
725 // Young generation | |
726 size_t scaled_eden_heap_delta = 0; | |
727 // Can the increment to the generation be scaled? | |
728 if (gc_cost() >= 0.0 && minor_gc_cost() >= 0.0) { | |
729 size_t eden_heap_delta = | |
730 eden_increment_with_supplement_aligned_up(*desired_eden_size_ptr); | |
731 double scale_by_ratio = minor_gc_cost() / gc_cost(); | |
732 assert(scale_by_ratio <= 1.0 && scale_by_ratio >= 0.0, "Scaling is wrong"); | |
733 scaled_eden_heap_delta = | |
734 (size_t) (scale_by_ratio * (double) eden_heap_delta); | |
735 if (PrintAdaptiveSizePolicy && Verbose) { | |
736 gclog_or_tty->print_cr( | |
737 "Scaled eden increment: " SIZE_FORMAT " by %f down to " | |
738 SIZE_FORMAT, | |
739 eden_heap_delta, scale_by_ratio, scaled_eden_heap_delta); | |
740 } | |
741 } else if (minor_gc_cost() >= 0.0) { | |
742 // Scaling is not going to work. If the minor gc time is the | |
743 // larger, give it a full increment. | |
744 if (minor_gc_cost() > major_gc_cost()) { | |
745 scaled_eden_heap_delta = | |
746 eden_increment_with_supplement_aligned_up(*desired_eden_size_ptr); | |
747 } | |
748 } else { | |
749 // Don't expect to get here but it's ok if it does | |
750 // in the product build since the delta will be 0 | |
751 // and nothing will change. | |
752 assert(false, "Unexpected value for gc costs"); | |
753 } | |
754 | |
755 // Use a heuristic for some number of collections to give | |
756 // the averages time to settle down. | |
757 switch (AdaptiveSizeThroughPutPolicy) { | |
758 case 1: | |
759 if (minor_collection_estimator()->increment_will_decrease() || | |
760 (_young_gen_change_for_minor_throughput | |
761 <= AdaptiveSizePolicyInitializingSteps)) { | |
762 // Expand young generation size to reduce frequency of | |
763 // of collections. | |
764 if ((*desired_eden_size_ptr + scaled_eden_heap_delta) > | |
765 *desired_eden_size_ptr) { | |
766 *desired_eden_size_ptr = | |
767 *desired_eden_size_ptr + scaled_eden_heap_delta; | |
768 } | |
769 set_change_young_gen_for_throughput( | |
770 increase_young_gen_for_througput_true); | |
771 _young_gen_change_for_minor_throughput++; | |
772 } else { | |
773 // EXPERIMENTAL ADJUSTMENT | |
774 // Record that decreasing the young gen size would decrease | |
775 // the minor collection cost but don't do it. | |
776 // *desired_eden_size_ptr = _eden_size - | |
777 // eden_decrement_aligned_down(*desired_eden_size_ptr); | |
778 set_change_young_gen_for_throughput( | |
779 decrease_young_gen_for_througput_true); | |
780 } | |
781 break; | |
782 default: | |
783 if ((*desired_eden_size_ptr + scaled_eden_heap_delta) > | |
784 *desired_eden_size_ptr) { | |
785 *desired_eden_size_ptr = | |
786 *desired_eden_size_ptr + scaled_eden_heap_delta; | |
787 } | |
788 set_change_young_gen_for_throughput( | |
789 increase_young_gen_for_througput_true); | |
790 _young_gen_change_for_minor_throughput++; | |
791 } | |
792 | |
793 if (PrintAdaptiveSizePolicy && Verbose) { | |
794 gclog_or_tty->print_cr( | |
795 "adjusting eden for throughput (avg %f goal %f). desired_eden_size " | |
796 SIZE_FORMAT " eden delta " SIZE_FORMAT "\n", | |
797 mutator_cost(), _throughput_goal, | |
798 *desired_eden_size_ptr, scaled_eden_heap_delta); | |
799 } | |
800 } | |
801 | |
802 size_t PSAdaptiveSizePolicy::adjust_promo_for_footprint( | |
803 size_t desired_promo_size, size_t desired_sum) { | |
804 assert(desired_promo_size <= desired_sum, "Inconsistent parameters"); | |
805 set_decrease_for_footprint(decrease_old_gen_for_footprint_true); | |
806 | |
807 size_t change = promo_decrement(desired_promo_size); | |
808 change = scale_down(change, desired_promo_size, desired_sum); | |
809 | |
810 size_t reduced_size = desired_promo_size - change; | |
811 | |
812 if (PrintAdaptiveSizePolicy && Verbose) { | |
813 gclog_or_tty->print_cr( | |
814 "AdaptiveSizePolicy::compute_generation_free_space " | |
815 "adjusting tenured gen for footprint. " | |
816 "starting promo size " SIZE_FORMAT | |
817 " reduced promo size " SIZE_FORMAT, | |
818 " promo delta " SIZE_FORMAT, | |
819 desired_promo_size, reduced_size, change ); | |
820 } | |
821 | |
822 assert(reduced_size <= desired_promo_size, "Inconsistent result"); | |
823 return reduced_size; | |
824 } | |
825 | |
826 size_t PSAdaptiveSizePolicy::adjust_eden_for_footprint( | |
827 size_t desired_eden_size, size_t desired_sum) { | |
828 assert(desired_eden_size <= desired_sum, "Inconsistent parameters"); | |
829 set_decrease_for_footprint(decrease_young_gen_for_footprint_true); | |
830 | |
831 size_t change = eden_decrement(desired_eden_size); | |
832 change = scale_down(change, desired_eden_size, desired_sum); | |
833 | |
834 size_t reduced_size = desired_eden_size - change; | |
835 | |
836 if (PrintAdaptiveSizePolicy && Verbose) { | |
837 gclog_or_tty->print_cr( | |
838 "AdaptiveSizePolicy::compute_generation_free_space " | |
839 "adjusting eden for footprint. " | |
840 " starting eden size " SIZE_FORMAT | |
841 " reduced eden size " SIZE_FORMAT | |
842 " eden delta " SIZE_FORMAT, | |
843 desired_eden_size, reduced_size, change); | |
844 } | |
845 | |
846 assert(reduced_size <= desired_eden_size, "Inconsistent result"); | |
847 return reduced_size; | |
848 } | |
849 | |
850 // Scale down "change" by the factor | |
851 // part / total | |
852 // Don't align the results. | |
853 | |
854 size_t PSAdaptiveSizePolicy::scale_down(size_t change, | |
855 double part, | |
856 double total) { | |
857 assert(part <= total, "Inconsistent input"); | |
858 size_t reduced_change = change; | |
859 if (total > 0) { | |
860 double fraction = part / total; | |
861 reduced_change = (size_t) (fraction * (double) change); | |
862 } | |
863 assert(reduced_change <= change, "Inconsistent result"); | |
864 return reduced_change; | |
865 } | |
866 | |
867 size_t PSAdaptiveSizePolicy::eden_increment(size_t cur_eden, | |
868 uint percent_change) { | |
869 size_t eden_heap_delta; | |
870 eden_heap_delta = cur_eden / 100 * percent_change; | |
871 return eden_heap_delta; | |
872 } | |
873 | |
874 size_t PSAdaptiveSizePolicy::eden_increment(size_t cur_eden) { | |
875 return eden_increment(cur_eden, YoungGenerationSizeIncrement); | |
876 } | |
877 | |
878 size_t PSAdaptiveSizePolicy::eden_increment_aligned_up(size_t cur_eden) { | |
879 size_t result = eden_increment(cur_eden, YoungGenerationSizeIncrement); | |
880 return align_size_up(result, _intra_generation_alignment); | |
881 } | |
882 | |
883 size_t PSAdaptiveSizePolicy::eden_increment_aligned_down(size_t cur_eden) { | |
884 size_t result = eden_increment(cur_eden); | |
885 return align_size_down(result, _intra_generation_alignment); | |
886 } | |
887 | |
888 size_t PSAdaptiveSizePolicy::eden_increment_with_supplement_aligned_up( | |
889 size_t cur_eden) { | |
890 size_t result = eden_increment(cur_eden, | |
891 YoungGenerationSizeIncrement + _young_gen_size_increment_supplement); | |
892 return align_size_up(result, _intra_generation_alignment); | |
893 } | |
894 | |
895 size_t PSAdaptiveSizePolicy::eden_decrement_aligned_down(size_t cur_eden) { | |
896 size_t eden_heap_delta = eden_decrement(cur_eden); | |
897 return align_size_down(eden_heap_delta, _intra_generation_alignment); | |
898 } | |
899 | |
900 size_t PSAdaptiveSizePolicy::eden_decrement(size_t cur_eden) { | |
901 size_t eden_heap_delta = eden_increment(cur_eden) / | |
902 AdaptiveSizeDecrementScaleFactor; | |
903 return eden_heap_delta; | |
904 } | |
905 | |
906 size_t PSAdaptiveSizePolicy::promo_increment(size_t cur_promo, | |
907 uint percent_change) { | |
908 size_t promo_heap_delta; | |
909 promo_heap_delta = cur_promo / 100 * percent_change; | |
910 return promo_heap_delta; | |
911 } | |
912 | |
913 size_t PSAdaptiveSizePolicy::promo_increment(size_t cur_promo) { | |
914 return promo_increment(cur_promo, TenuredGenerationSizeIncrement); | |
915 } | |
916 | |
917 size_t PSAdaptiveSizePolicy::promo_increment_aligned_up(size_t cur_promo) { | |
918 size_t result = promo_increment(cur_promo, TenuredGenerationSizeIncrement); | |
919 return align_size_up(result, _intra_generation_alignment); | |
920 } | |
921 | |
922 size_t PSAdaptiveSizePolicy::promo_increment_aligned_down(size_t cur_promo) { | |
923 size_t result = promo_increment(cur_promo, TenuredGenerationSizeIncrement); | |
924 return align_size_down(result, _intra_generation_alignment); | |
925 } | |
926 | |
927 size_t PSAdaptiveSizePolicy::promo_increment_with_supplement_aligned_up( | |
928 size_t cur_promo) { | |
929 size_t result = promo_increment(cur_promo, | |
930 TenuredGenerationSizeIncrement + _old_gen_size_increment_supplement); | |
931 return align_size_up(result, _intra_generation_alignment); | |
932 } | |
933 | |
934 size_t PSAdaptiveSizePolicy::promo_decrement_aligned_down(size_t cur_promo) { | |
935 size_t promo_heap_delta = promo_decrement(cur_promo); | |
936 return align_size_down(promo_heap_delta, _intra_generation_alignment); | |
937 } | |
938 | |
939 size_t PSAdaptiveSizePolicy::promo_decrement(size_t cur_promo) { | |
940 size_t promo_heap_delta = promo_increment(cur_promo); | |
941 promo_heap_delta = promo_heap_delta / AdaptiveSizeDecrementScaleFactor; | |
942 return promo_heap_delta; | |
943 } | |
944 | |
945 int PSAdaptiveSizePolicy::compute_survivor_space_size_and_threshold( | |
946 bool is_survivor_overflow, | |
947 int tenuring_threshold, | |
948 size_t survivor_limit) { | |
949 assert(survivor_limit >= _intra_generation_alignment, | |
950 "survivor_limit too small"); | |
951 assert((size_t)align_size_down(survivor_limit, _intra_generation_alignment) | |
952 == survivor_limit, "survivor_limit not aligned"); | |
953 | |
954 // This method is called even if the tenuring threshold and survivor | |
955 // spaces are not adjusted so that the averages are sampled above. | |
956 if (!UsePSAdaptiveSurvivorSizePolicy || | |
957 !young_gen_policy_is_ready()) { | |
958 return tenuring_threshold; | |
959 } | |
960 | |
961 // We'll decide whether to increase or decrease the tenuring | |
962 // threshold based partly on the newly computed survivor size | |
963 // (if we hit the maximum limit allowed, we'll always choose to | |
964 // decrement the threshold). | |
965 bool incr_tenuring_threshold = false; | |
966 bool decr_tenuring_threshold = false; | |
967 | |
968 set_decrement_tenuring_threshold_for_gc_cost(false); | |
969 set_increment_tenuring_threshold_for_gc_cost(false); | |
970 set_decrement_tenuring_threshold_for_survivor_limit(false); | |
971 | |
972 if (!is_survivor_overflow) { | |
973 // Keep running averages on how much survived | |
974 | |
975 // We use the tenuring threshold to equalize the cost of major | |
976 // and minor collections. | |
977 // ThresholdTolerance is used to indicate how sensitive the | |
978 // tenuring threshold is to differences in cost betweent the | |
979 // collection types. | |
980 | |
981 // Get the times of interest. This involves a little work, so | |
982 // we cache the values here. | |
983 const double major_cost = major_gc_cost(); | |
984 const double minor_cost = minor_gc_cost(); | |
985 | |
986 if (minor_cost > major_cost * _threshold_tolerance_percent) { | |
987 // Minor times are getting too long; lower the threshold so | |
988 // less survives and more is promoted. | |
989 decr_tenuring_threshold = true; | |
990 set_decrement_tenuring_threshold_for_gc_cost(true); | |
991 } else if (major_cost > minor_cost * _threshold_tolerance_percent) { | |
992 // Major times are too long, so we want less promotion. | |
993 incr_tenuring_threshold = true; | |
994 set_increment_tenuring_threshold_for_gc_cost(true); | |
995 } | |
996 | |
997 } else { | |
998 // Survivor space overflow occurred, so promoted and survived are | |
999 // not accurate. We'll make our best guess by combining survived | |
1000 // and promoted and count them as survivors. | |
1001 // | |
1002 // We'll lower the tenuring threshold to see if we can correct | |
1003 // things. Also, set the survivor size conservatively. We're | |
1004 // trying to avoid many overflows from occurring if defnew size | |
1005 // is just too small. | |
1006 | |
1007 decr_tenuring_threshold = true; | |
1008 } | |
1009 | |
1010 // The padded average also maintains a deviation from the average; | |
1011 // we use this to see how good of an estimate we have of what survived. | |
1012 // We're trying to pad the survivor size as little as possible without | |
1013 // overflowing the survivor spaces. | |
1014 size_t target_size = align_size_up((size_t)_avg_survived->padded_average(), | |
1015 _intra_generation_alignment); | |
1016 target_size = MAX2(target_size, _intra_generation_alignment); | |
1017 | |
1018 if (target_size > survivor_limit) { | |
1019 // Target size is bigger than we can handle. Let's also reduce | |
1020 // the tenuring threshold. | |
1021 target_size = survivor_limit; | |
1022 decr_tenuring_threshold = true; | |
1023 set_decrement_tenuring_threshold_for_survivor_limit(true); | |
1024 } | |
1025 | |
1026 // Finally, increment or decrement the tenuring threshold, as decided above. | |
1027 // We test for decrementing first, as we might have hit the target size | |
1028 // limit. | |
1029 if (decr_tenuring_threshold && !(AlwaysTenure || NeverTenure)) { | |
1030 if (tenuring_threshold > 1) { | |
1031 tenuring_threshold--; | |
1032 } | |
1033 } else if (incr_tenuring_threshold && !(AlwaysTenure || NeverTenure)) { | |
1034 if (tenuring_threshold < MaxTenuringThreshold) { | |
1035 tenuring_threshold++; | |
1036 } | |
1037 } | |
1038 | |
1039 // We keep a running average of the amount promoted which is used | |
1040 // to decide when we should collect the old generation (when | |
1041 // the amount of old gen free space is less than what we expect to | |
1042 // promote). | |
1043 | |
1044 if (PrintAdaptiveSizePolicy) { | |
1045 // A little more detail if Verbose is on | |
1046 if (Verbose) { | |
1047 gclog_or_tty->print( " avg_survived: %f" | |
1048 " avg_deviation: %f", | |
1049 _avg_survived->average(), | |
1050 _avg_survived->deviation()); | |
1051 } | |
1052 | |
1053 gclog_or_tty->print( " avg_survived_padded_avg: %f", | |
1054 _avg_survived->padded_average()); | |
1055 | |
1056 if (Verbose) { | |
1057 gclog_or_tty->print( " avg_promoted_avg: %f" | |
1058 " avg_promoted_dev: %f", | |
1059 avg_promoted()->average(), | |
1060 avg_promoted()->deviation()); | |
1061 } | |
1062 | |
1063 gclog_or_tty->print( " avg_promoted_padded_avg: %f" | |
1064 " avg_pretenured_padded_avg: %f" | |
1065 " tenuring_thresh: %d" | |
1066 " target_size: " SIZE_FORMAT, | |
1067 avg_promoted()->padded_average(), | |
1068 _avg_pretenured->padded_average(), | |
1069 tenuring_threshold, target_size); | |
1070 tty->cr(); | |
1071 } | |
1072 | |
1073 set_survivor_size(target_size); | |
1074 | |
1075 return tenuring_threshold; | |
1076 } | |
1077 | |
1078 void PSAdaptiveSizePolicy::update_averages(bool is_survivor_overflow, | |
1079 size_t survived, | |
1080 size_t promoted) { | |
1081 // Update averages | |
1082 if (!is_survivor_overflow) { | |
1083 // Keep running averages on how much survived | |
1084 _avg_survived->sample(survived); | |
1085 } else { | |
1086 size_t survived_guess = survived + promoted; | |
1087 _avg_survived->sample(survived_guess); | |
1088 } | |
1089 avg_promoted()->sample(promoted + _avg_pretenured->padded_average()); | |
1090 | |
1091 if (PrintAdaptiveSizePolicy) { | |
1092 gclog_or_tty->print( | |
1093 "AdaptiveSizePolicy::compute_survivor_space_size_and_thresh:" | |
1094 " survived: " SIZE_FORMAT | |
1095 " promoted: " SIZE_FORMAT | |
1096 " overflow: %s", | |
1097 survived, promoted, is_survivor_overflow ? "true" : "false"); | |
1098 } | |
1099 } | |
1100 | |
1101 bool PSAdaptiveSizePolicy::print_adaptive_size_policy_on(outputStream* st) | |
1102 const { | |
1103 | |
1104 if (!UseAdaptiveSizePolicy) return false; | |
1105 | |
1106 return AdaptiveSizePolicy::print_adaptive_size_policy_on( | |
1107 st, | |
1108 PSScavenge::tenuring_threshold()); | |
1109 } |