Mercurial > hg > graal-jvmci-8
annotate src/share/vm/gc_implementation/parallelScavenge/psAdaptiveSizePolicy.cpp @ 1571:2d127394260e
6916623: Align object to 16 bytes to use Compressed Oops with java heap up to 64Gb
Summary: Added new product ObjectAlignmentInBytes flag to control object alignment.
Reviewed-by: twisti, ysr, iveresov
author | kvn |
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date | Thu, 27 May 2010 18:01:56 -0700 |
parents | 0bfd3fb24150 |
children | c18cbe5936b8 |
rev | line source |
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0 | 1 /* |
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2 * Copyright 2002-2010 Sun Microsystems, Inc. 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 * | |
19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, | |
20 * CA 95054 USA or visit www.sun.com if you need additional information or | |
21 * have any questions. | |
22 * | |
23 */ | |
24 | |
25 #include "incls/_precompiled.incl" | |
26 #include "incls/_psAdaptiveSizePolicy.cpp.incl" | |
27 | |
28 #include <math.h> | |
29 | |
30 PSAdaptiveSizePolicy::PSAdaptiveSizePolicy(size_t init_eden_size, | |
31 size_t init_promo_size, | |
32 size_t init_survivor_size, | |
33 size_t intra_generation_alignment, | |
34 double gc_pause_goal_sec, | |
35 double gc_minor_pause_goal_sec, | |
36 uint gc_cost_ratio) : | |
37 AdaptiveSizePolicy(init_eden_size, | |
38 init_promo_size, | |
39 init_survivor_size, | |
40 gc_pause_goal_sec, | |
41 gc_cost_ratio), | |
42 _collection_cost_margin_fraction(AdaptiveSizePolicyCollectionCostMargin/ | |
43 100.0), | |
44 _intra_generation_alignment(intra_generation_alignment), | |
45 _live_at_last_full_gc(init_promo_size), | |
46 _gc_minor_pause_goal_sec(gc_minor_pause_goal_sec), | |
47 _latest_major_mutator_interval_seconds(0), | |
48 _young_gen_change_for_major_pause_count(0) | |
49 { | |
50 // Sizing policy statistics | |
51 _avg_major_pause = | |
52 new AdaptivePaddedAverage(AdaptiveTimeWeight, PausePadding); | |
53 _avg_minor_interval = new AdaptiveWeightedAverage(AdaptiveTimeWeight); | |
54 _avg_major_interval = new AdaptiveWeightedAverage(AdaptiveTimeWeight); | |
55 | |
56 _avg_base_footprint = new AdaptiveWeightedAverage(AdaptiveSizePolicyWeight); | |
57 _major_pause_old_estimator = | |
58 new LinearLeastSquareFit(AdaptiveSizePolicyWeight); | |
59 _major_pause_young_estimator = | |
60 new LinearLeastSquareFit(AdaptiveSizePolicyWeight); | |
61 _major_collection_estimator = | |
62 new LinearLeastSquareFit(AdaptiveSizePolicyWeight); | |
63 | |
64 _young_gen_size_increment_supplement = YoungGenerationSizeSupplement; | |
65 _old_gen_size_increment_supplement = TenuredGenerationSizeSupplement; | |
66 | |
67 // Start the timers | |
68 _major_timer.start(); | |
69 | |
70 _old_gen_policy_is_ready = false; | |
71 } | |
72 | |
73 void PSAdaptiveSizePolicy::major_collection_begin() { | |
74 // Update the interval time | |
75 _major_timer.stop(); | |
76 // Save most recent collection time | |
77 _latest_major_mutator_interval_seconds = _major_timer.seconds(); | |
78 _major_timer.reset(); | |
79 _major_timer.start(); | |
80 } | |
81 | |
82 void PSAdaptiveSizePolicy::update_minor_pause_old_estimator( | |
83 double minor_pause_in_ms) { | |
84 double promo_size_in_mbytes = ((double)_promo_size)/((double)M); | |
85 _minor_pause_old_estimator->update(promo_size_in_mbytes, | |
86 minor_pause_in_ms); | |
87 } | |
88 | |
89 void PSAdaptiveSizePolicy::major_collection_end(size_t amount_live, | |
90 GCCause::Cause gc_cause) { | |
91 // Update the pause time. | |
92 _major_timer.stop(); | |
93 | |
94 if (gc_cause != GCCause::_java_lang_system_gc || | |
95 UseAdaptiveSizePolicyWithSystemGC) { | |
96 double major_pause_in_seconds = _major_timer.seconds(); | |
97 double major_pause_in_ms = major_pause_in_seconds * MILLIUNITS; | |
98 | |
99 // Sample for performance counter | |
100 _avg_major_pause->sample(major_pause_in_seconds); | |
101 | |
102 // Cost of collection (unit-less) | |
103 double collection_cost = 0.0; | |
104 if ((_latest_major_mutator_interval_seconds > 0.0) && | |
105 (major_pause_in_seconds > 0.0)) { | |
106 double interval_in_seconds = | |
107 _latest_major_mutator_interval_seconds + major_pause_in_seconds; | |
108 collection_cost = | |
109 major_pause_in_seconds / interval_in_seconds; | |
110 avg_major_gc_cost()->sample(collection_cost); | |
111 | |
112 // Sample for performance counter | |
113 _avg_major_interval->sample(interval_in_seconds); | |
114 } | |
115 | |
116 // Calculate variables used to estimate pause time vs. gen sizes | |
117 double eden_size_in_mbytes = ((double)_eden_size)/((double)M); | |
118 double promo_size_in_mbytes = ((double)_promo_size)/((double)M); | |
119 _major_pause_old_estimator->update(promo_size_in_mbytes, | |
120 major_pause_in_ms); | |
121 _major_pause_young_estimator->update(eden_size_in_mbytes, | |
122 major_pause_in_ms); | |
123 | |
124 if (PrintAdaptiveSizePolicy && Verbose) { | |
125 gclog_or_tty->print("psAdaptiveSizePolicy::major_collection_end: " | |
126 "major gc cost: %f average: %f", collection_cost, | |
127 avg_major_gc_cost()->average()); | |
128 gclog_or_tty->print_cr(" major pause: %f major period %f", | |
129 major_pause_in_ms, | |
130 _latest_major_mutator_interval_seconds * MILLIUNITS); | |
131 } | |
132 | |
133 // Calculate variable used to estimate collection cost vs. gen sizes | |
134 assert(collection_cost >= 0.0, "Expected to be non-negative"); | |
135 _major_collection_estimator->update(promo_size_in_mbytes, | |
136 collection_cost); | |
137 } | |
138 | |
139 // Update the amount live at the end of a full GC | |
140 _live_at_last_full_gc = amount_live; | |
141 | |
142 // The policy does not have enough data until at least some major collections | |
143 // have been done. | |
144 if (_avg_major_pause->count() >= AdaptiveSizePolicyReadyThreshold) { | |
145 _old_gen_policy_is_ready = true; | |
146 } | |
147 | |
148 // Interval times use this timer to measure the interval that | |
149 // the mutator runs. Reset after the GC pause has been measured. | |
150 _major_timer.reset(); | |
151 _major_timer.start(); | |
152 } | |
153 | |
154 // If the remaining free space in the old generation is less that | |
155 // that expected to be needed by the next collection, do a full | |
156 // collection now. | |
157 bool PSAdaptiveSizePolicy::should_full_GC(size_t old_free_in_bytes) { | |
158 | |
159 // A similar test is done in the scavenge's should_attempt_scavenge(). If | |
160 // this is changed, decide if that test should also be changed. | |
161 bool result = padded_average_promoted_in_bytes() > (float) old_free_in_bytes; | |
162 if (PrintGCDetails && Verbose) { | |
163 if (result) { | |
164 gclog_or_tty->print(" full after scavenge: "); | |
165 } else { | |
166 gclog_or_tty->print(" no full after scavenge: "); | |
167 } | |
168 gclog_or_tty->print_cr(" average_promoted " SIZE_FORMAT | |
169 " padded_average_promoted " SIZE_FORMAT | |
170 " free in old gen " SIZE_FORMAT, | |
171 (size_t) average_promoted_in_bytes(), | |
172 (size_t) padded_average_promoted_in_bytes(), | |
173 old_free_in_bytes); | |
174 } | |
175 return result; | |
176 } | |
177 | |
178 void PSAdaptiveSizePolicy::clear_generation_free_space_flags() { | |
179 | |
180 AdaptiveSizePolicy::clear_generation_free_space_flags(); | |
181 | |
182 set_change_old_gen_for_min_pauses(0); | |
183 | |
184 set_change_young_gen_for_maj_pauses(0); | |
185 } | |
186 | |
187 // If this is not a full GC, only test and modify the young generation. | |
188 | |
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189 void PSAdaptiveSizePolicy::compute_generation_free_space( |
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190 size_t young_live, |
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191 size_t eden_live, |
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192 size_t old_live, |
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193 size_t perm_live, |
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194 size_t cur_eden, |
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195 size_t max_old_gen_size, |
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196 size_t max_eden_size, |
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197 bool is_full_gc, |
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198 GCCause::Cause gc_cause, |
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199 CollectorPolicy* collector_policy) { |
0 | 200 |
201 // Update statistics | |
202 // Time statistics are updated as we go, update footprint stats here | |
203 _avg_base_footprint->sample(BaseFootPrintEstimate + perm_live); | |
204 avg_young_live()->sample(young_live); | |
205 avg_eden_live()->sample(eden_live); | |
206 if (is_full_gc) { | |
207 // old_live is only accurate after a full gc | |
208 avg_old_live()->sample(old_live); | |
209 } | |
210 | |
211 // This code used to return if the policy was not ready , i.e., | |
212 // policy_is_ready() returning false. The intent was that | |
213 // decisions below needed major collection times and so could | |
214 // not be made before two major collections. A consequence was | |
215 // adjustments to the young generation were not done until after | |
216 // two major collections even if the minor collections times | |
217 // exceeded the requested goals. Now let the young generation | |
218 // adjust for the minor collection times. Major collection times | |
219 // will be zero for the first collection and will naturally be | |
220 // ignored. Tenured generation adjustments are only made at the | |
221 // full collections so until the second major collection has | |
222 // been reached, no tenured generation adjustments will be made. | |
223 | |
224 // Until we know better, desired promotion size uses the last calculation | |
225 size_t desired_promo_size = _promo_size; | |
226 | |
227 // Start eden at the current value. The desired value that is stored | |
228 // in _eden_size is not bounded by constraints of the heap and can | |
229 // run away. | |
230 // | |
231 // As expected setting desired_eden_size to the current | |
232 // value of desired_eden_size as a starting point | |
233 // caused desired_eden_size to grow way too large and caused | |
234 // an overflow down stream. It may have improved performance in | |
235 // some case but is dangerous. | |
236 size_t desired_eden_size = cur_eden; | |
237 | |
238 #ifdef ASSERT | |
239 size_t original_promo_size = desired_promo_size; | |
240 size_t original_eden_size = desired_eden_size; | |
241 #endif | |
242 | |
243 // Cache some values. There's a bit of work getting these, so | |
244 // we might save a little time. | |
245 const double major_cost = major_gc_cost(); | |
246 const double minor_cost = minor_gc_cost(); | |
247 | |
248 // Used for diagnostics | |
249 clear_generation_free_space_flags(); | |
250 | |
251 // Limits on our growth | |
252 size_t promo_limit = (size_t)(max_old_gen_size - avg_old_live()->average()); | |
253 | |
254 // This method sets the desired eden size. That plus the | |
255 // desired survivor space sizes sets the desired young generation | |
256 // size. This methods does not know what the desired survivor | |
257 // size is but expects that other policy will attempt to make | |
258 // the survivor sizes compatible with the live data in the | |
259 // young generation. This limit is an estimate of the space left | |
260 // in the young generation after the survivor spaces have been | |
261 // subtracted out. | |
262 size_t eden_limit = max_eden_size; | |
263 | |
264 // But don't force a promo size below the current promo size. Otherwise, | |
265 // the promo size will shrink for no good reason. | |
266 promo_limit = MAX2(promo_limit, _promo_size); | |
267 | |
268 const double gc_cost_limit = GCTimeLimit/100.0; | |
269 | |
270 // Which way should we go? | |
271 // if pause requirement is not met | |
272 // adjust size of any generation with average paus exceeding | |
273 // the pause limit. Adjust one pause at a time (the larger) | |
274 // and only make adjustments for the major pause at full collections. | |
275 // else if throughput requirement not met | |
276 // adjust the size of the generation with larger gc time. Only | |
277 // adjust one generation at a time. | |
278 // else | |
279 // adjust down the total heap size. Adjust down the larger of the | |
280 // generations. | |
281 | |
282 // Add some checks for a threshhold for a change. For example, | |
283 // a change less than the necessary alignment is probably not worth | |
284 // attempting. | |
285 | |
286 | |
287 if ((_avg_minor_pause->padded_average() > gc_pause_goal_sec()) || | |
288 (_avg_major_pause->padded_average() > gc_pause_goal_sec())) { | |
289 // | |
290 // Check pauses | |
291 // | |
292 // Make changes only to affect one of the pauses (the larger) | |
293 // at a time. | |
294 adjust_for_pause_time(is_full_gc, &desired_promo_size, &desired_eden_size); | |
295 | |
296 } else if (_avg_minor_pause->padded_average() > gc_minor_pause_goal_sec()) { | |
297 // Adjust only for the minor pause time goal | |
298 adjust_for_minor_pause_time(is_full_gc, &desired_promo_size, &desired_eden_size); | |
299 | |
300 } else if(adjusted_mutator_cost() < _throughput_goal) { | |
301 // This branch used to require that (mutator_cost() > 0.0 in 1.4.2. | |
302 // This sometimes resulted in skipping to the minimize footprint | |
303 // code. Change this to try and reduce GC time if mutator time is | |
304 // negative for whatever reason. Or for future consideration, | |
305 // bail out of the code if mutator time is negative. | |
306 // | |
307 // Throughput | |
308 // | |
309 assert(major_cost >= 0.0, "major cost is < 0.0"); | |
310 assert(minor_cost >= 0.0, "minor cost is < 0.0"); | |
311 // Try to reduce the GC times. | |
312 adjust_for_throughput(is_full_gc, &desired_promo_size, &desired_eden_size); | |
313 | |
314 } else { | |
315 | |
316 // Be conservative about reducing the footprint. | |
317 // Do a minimum number of major collections first. | |
318 // Have reasonable averages for major and minor collections costs. | |
319 if (UseAdaptiveSizePolicyFootprintGoal && | |
320 young_gen_policy_is_ready() && | |
321 avg_major_gc_cost()->average() >= 0.0 && | |
322 avg_minor_gc_cost()->average() >= 0.0) { | |
323 size_t desired_sum = desired_eden_size + desired_promo_size; | |
324 desired_eden_size = adjust_eden_for_footprint(desired_eden_size, | |
325 desired_sum); | |
326 if (is_full_gc) { | |
327 set_decide_at_full_gc(decide_at_full_gc_true); | |
328 desired_promo_size = adjust_promo_for_footprint(desired_promo_size, | |
329 desired_sum); | |
330 } | |
331 } | |
332 } | |
333 | |
334 // Note we make the same tests as in the code block below; the code | |
335 // seems a little easier to read with the printing in another block. | |
336 if (PrintAdaptiveSizePolicy) { | |
337 if (desired_promo_size > promo_limit) { | |
338 // "free_in_old_gen" was the original value for used for promo_limit | |
339 size_t free_in_old_gen = (size_t)(max_old_gen_size - avg_old_live()->average()); | |
340 gclog_or_tty->print_cr( | |
341 "PSAdaptiveSizePolicy::compute_generation_free_space limits:" | |
342 " desired_promo_size: " SIZE_FORMAT | |
343 " promo_limit: " SIZE_FORMAT | |
344 " free_in_old_gen: " SIZE_FORMAT | |
345 " max_old_gen_size: " SIZE_FORMAT | |
346 " avg_old_live: " SIZE_FORMAT, | |
347 desired_promo_size, promo_limit, free_in_old_gen, | |
348 max_old_gen_size, (size_t) avg_old_live()->average()); | |
349 } | |
350 if (desired_eden_size > eden_limit) { | |
351 gclog_or_tty->print_cr( | |
352 "AdaptiveSizePolicy::compute_generation_free_space limits:" | |
353 " desired_eden_size: " SIZE_FORMAT | |
354 " old_eden_size: " SIZE_FORMAT | |
355 " eden_limit: " SIZE_FORMAT | |
356 " cur_eden: " SIZE_FORMAT | |
357 " max_eden_size: " SIZE_FORMAT | |
358 " avg_young_live: " SIZE_FORMAT, | |
359 desired_eden_size, _eden_size, eden_limit, cur_eden, | |
360 max_eden_size, (size_t)avg_young_live()->average()); | |
361 } | |
362 if (gc_cost() > gc_cost_limit) { | |
363 gclog_or_tty->print_cr( | |
364 "AdaptiveSizePolicy::compute_generation_free_space: gc time limit" | |
365 " gc_cost: %f " | |
366 " GCTimeLimit: %d", | |
367 gc_cost(), GCTimeLimit); | |
368 } | |
369 } | |
370 | |
371 // Align everything and make a final limit check | |
372 const size_t alignment = _intra_generation_alignment; | |
373 desired_eden_size = align_size_up(desired_eden_size, alignment); | |
374 desired_eden_size = MAX2(desired_eden_size, alignment); | |
375 desired_promo_size = align_size_up(desired_promo_size, alignment); | |
376 desired_promo_size = MAX2(desired_promo_size, alignment); | |
377 | |
378 eden_limit = align_size_down(eden_limit, alignment); | |
379 promo_limit = align_size_down(promo_limit, alignment); | |
380 | |
381 // Is too much time being spent in GC? | |
382 // Is the heap trying to grow beyond it's limits? | |
383 | |
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384 const size_t free_in_old_gen = |
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385 (size_t)(max_old_gen_size - avg_old_live()->average()); |
0 | 386 if (desired_promo_size > free_in_old_gen && desired_eden_size > eden_limit) { |
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387 check_gc_overhead_limit(young_live, |
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388 eden_live, |
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389 max_old_gen_size, |
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390 max_eden_size, |
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391 is_full_gc, |
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392 gc_cause, |
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393 collector_policy); |
0 | 394 } |
395 | |
396 | |
397 // And one last limit check, now that we've aligned things. | |
398 if (desired_eden_size > eden_limit) { | |
399 // If the policy says to get a larger eden but | |
400 // is hitting the limit, don't decrease eden. | |
401 // This can lead to a general drifting down of the | |
402 // eden size. Let the tenuring calculation push more | |
403 // into the old gen. | |
404 desired_eden_size = MAX2(eden_limit, cur_eden); | |
405 } | |
406 desired_promo_size = MIN2(desired_promo_size, promo_limit); | |
407 | |
408 | |
409 if (PrintAdaptiveSizePolicy) { | |
410 // Timing stats | |
411 gclog_or_tty->print( | |
412 "PSAdaptiveSizePolicy::compute_generation_free_space: costs" | |
413 " minor_time: %f" | |
414 " major_cost: %f" | |
415 " mutator_cost: %f" | |
416 " throughput_goal: %f", | |
417 minor_gc_cost(), major_gc_cost(), mutator_cost(), | |
418 _throughput_goal); | |
419 | |
420 // We give more details if Verbose is set | |
421 if (Verbose) { | |
422 gclog_or_tty->print( " minor_pause: %f" | |
423 " major_pause: %f" | |
424 " minor_interval: %f" | |
425 " major_interval: %f" | |
426 " pause_goal: %f", | |
427 _avg_minor_pause->padded_average(), | |
428 _avg_major_pause->padded_average(), | |
429 _avg_minor_interval->average(), | |
430 _avg_major_interval->average(), | |
431 gc_pause_goal_sec()); | |
432 } | |
433 | |
434 // Footprint stats | |
435 gclog_or_tty->print( " live_space: " SIZE_FORMAT | |
436 " free_space: " SIZE_FORMAT, | |
437 live_space(), free_space()); | |
438 // More detail | |
439 if (Verbose) { | |
440 gclog_or_tty->print( " base_footprint: " SIZE_FORMAT | |
441 " avg_young_live: " SIZE_FORMAT | |
442 " avg_old_live: " SIZE_FORMAT, | |
443 (size_t)_avg_base_footprint->average(), | |
444 (size_t)avg_young_live()->average(), | |
445 (size_t)avg_old_live()->average()); | |
446 } | |
447 | |
448 // And finally, our old and new sizes. | |
449 gclog_or_tty->print(" old_promo_size: " SIZE_FORMAT | |
450 " old_eden_size: " SIZE_FORMAT | |
451 " desired_promo_size: " SIZE_FORMAT | |
452 " desired_eden_size: " SIZE_FORMAT, | |
453 _promo_size, _eden_size, | |
454 desired_promo_size, desired_eden_size); | |
455 gclog_or_tty->cr(); | |
456 } | |
457 | |
458 decay_supplemental_growth(is_full_gc); | |
459 | |
460 set_promo_size(desired_promo_size); | |
461 set_eden_size(desired_eden_size); | |
462 }; | |
463 | |
464 void PSAdaptiveSizePolicy::decay_supplemental_growth(bool is_full_gc) { | |
465 // Decay the supplemental increment? Decay the supplement growth | |
466 // factor even if it is not used. It is only meant to give a boost | |
467 // to the initial growth and if it is not used, then it was not | |
468 // needed. | |
469 if (is_full_gc) { | |
470 // Don't wait for the threshold value for the major collections. If | |
471 // here, the supplemental growth term was used and should decay. | |
472 if ((_avg_major_pause->count() % TenuredGenerationSizeSupplementDecay) | |
473 == 0) { | |
474 _old_gen_size_increment_supplement = | |
475 _old_gen_size_increment_supplement >> 1; | |
476 } | |
477 } else { | |
478 if ((_avg_minor_pause->count() >= AdaptiveSizePolicyReadyThreshold) && | |
479 (_avg_minor_pause->count() % YoungGenerationSizeSupplementDecay) == 0) { | |
480 _young_gen_size_increment_supplement = | |
481 _young_gen_size_increment_supplement >> 1; | |
482 } | |
483 } | |
484 } | |
485 | |
486 void PSAdaptiveSizePolicy::adjust_for_minor_pause_time(bool is_full_gc, | |
487 size_t* desired_promo_size_ptr, size_t* desired_eden_size_ptr) { | |
488 | |
489 // Adjust the young generation size to reduce pause time of | |
490 // of collections. | |
491 // | |
492 // The AdaptiveSizePolicyInitializingSteps test is not used | |
493 // here. It has not seemed to be needed but perhaps should | |
494 // be added for consistency. | |
495 if (minor_pause_young_estimator()->decrement_will_decrease()) { | |
496 // reduce eden size | |
497 set_change_young_gen_for_min_pauses( | |
498 decrease_young_gen_for_min_pauses_true); | |
499 *desired_eden_size_ptr = *desired_eden_size_ptr - | |
500 eden_decrement_aligned_down(*desired_eden_size_ptr); | |
501 } else { | |
502 // EXPERIMENTAL ADJUSTMENT | |
503 // Only record that the estimator indicated such an action. | |
504 // *desired_eden_size_ptr = *desired_eden_size_ptr + eden_heap_delta; | |
505 set_change_young_gen_for_min_pauses( | |
506 increase_young_gen_for_min_pauses_true); | |
507 } | |
508 if (PSAdjustTenuredGenForMinorPause) { | |
509 // If the desired eden size is as small as it will get, | |
510 // try to adjust the old gen size. | |
511 if (*desired_eden_size_ptr <= _intra_generation_alignment) { | |
512 // Vary the old gen size to reduce the young gen pause. This | |
513 // may not be a good idea. This is just a test. | |
514 if (minor_pause_old_estimator()->decrement_will_decrease()) { | |
515 set_change_old_gen_for_min_pauses( | |
516 decrease_old_gen_for_min_pauses_true); | |
517 *desired_promo_size_ptr = | |
518 _promo_size - promo_decrement_aligned_down(*desired_promo_size_ptr); | |
519 } else { | |
520 set_change_old_gen_for_min_pauses( | |
521 increase_old_gen_for_min_pauses_true); | |
522 size_t promo_heap_delta = | |
523 promo_increment_with_supplement_aligned_up(*desired_promo_size_ptr); | |
524 if ((*desired_promo_size_ptr + promo_heap_delta) > | |
525 *desired_promo_size_ptr) { | |
526 *desired_promo_size_ptr = | |
527 _promo_size + promo_heap_delta; | |
528 } | |
529 } | |
530 } | |
531 } | |
532 } | |
533 | |
534 void PSAdaptiveSizePolicy::adjust_for_pause_time(bool is_full_gc, | |
535 size_t* desired_promo_size_ptr, | |
536 size_t* desired_eden_size_ptr) { | |
537 | |
538 size_t promo_heap_delta = 0; | |
539 size_t eden_heap_delta = 0; | |
540 // Add some checks for a threshhold for a change. For example, | |
541 // a change less than the required alignment is probably not worth | |
542 // attempting. | |
543 if (is_full_gc) { | |
544 set_decide_at_full_gc(decide_at_full_gc_true); | |
545 } | |
546 | |
547 if (_avg_minor_pause->padded_average() > _avg_major_pause->padded_average()) { | |
548 adjust_for_minor_pause_time(is_full_gc, | |
549 desired_promo_size_ptr, | |
550 desired_eden_size_ptr); | |
551 // major pause adjustments | |
552 } else if (is_full_gc) { | |
553 // Adjust for the major pause time only at full gc's because the | |
554 // affects of a change can only be seen at full gc's. | |
555 | |
556 // Reduce old generation size to reduce pause? | |
557 if (major_pause_old_estimator()->decrement_will_decrease()) { | |
558 // reduce old generation size | |
559 set_change_old_gen_for_maj_pauses(decrease_old_gen_for_maj_pauses_true); | |
560 promo_heap_delta = promo_decrement_aligned_down(*desired_promo_size_ptr); | |
561 *desired_promo_size_ptr = _promo_size - promo_heap_delta; | |
562 } else { | |
563 // EXPERIMENTAL ADJUSTMENT | |
564 // Only record that the estimator indicated such an action. | |
565 // *desired_promo_size_ptr = _promo_size + | |
566 // promo_increment_aligned_up(*desired_promo_size_ptr); | |
567 set_change_old_gen_for_maj_pauses(increase_old_gen_for_maj_pauses_true); | |
568 } | |
569 if (PSAdjustYoungGenForMajorPause) { | |
570 // If the promo size is at the minimum (i.e., the old gen | |
571 // size will not actually decrease), consider changing the | |
572 // young gen size. | |
573 if (*desired_promo_size_ptr < _intra_generation_alignment) { | |
574 // If increasing the young generation will decrease the old gen | |
575 // pause, do it. | |
576 // During startup there is noise in the statistics for deciding | |
577 // on whether to increase or decrease the young gen size. For | |
578 // some number of iterations, just try to increase the young | |
579 // gen size if the major pause is too long to try and establish | |
580 // good statistics for later decisions. | |
581 if (major_pause_young_estimator()->increment_will_decrease() || | |
582 (_young_gen_change_for_major_pause_count | |
583 <= AdaptiveSizePolicyInitializingSteps)) { | |
584 set_change_young_gen_for_maj_pauses( | |
585 increase_young_gen_for_maj_pauses_true); | |
586 eden_heap_delta = eden_increment_aligned_up(*desired_eden_size_ptr); | |
587 *desired_eden_size_ptr = _eden_size + eden_heap_delta; | |
588 _young_gen_change_for_major_pause_count++; | |
589 } else { | |
590 // Record that decreasing the young gen size would decrease | |
591 // the major pause | |
592 set_change_young_gen_for_maj_pauses( | |
593 decrease_young_gen_for_maj_pauses_true); | |
594 eden_heap_delta = eden_decrement_aligned_down(*desired_eden_size_ptr); | |
595 *desired_eden_size_ptr = _eden_size - eden_heap_delta; | |
596 } | |
597 } | |
598 } | |
599 } | |
600 | |
601 if (PrintAdaptiveSizePolicy && Verbose) { | |
602 gclog_or_tty->print_cr( | |
603 "AdaptiveSizePolicy::compute_generation_free_space " | |
604 "adjusting gen sizes for major pause (avg %f goal %f). " | |
605 "desired_promo_size " SIZE_FORMAT "desired_eden_size " | |
606 SIZE_FORMAT | |
607 " promo delta " SIZE_FORMAT " eden delta " SIZE_FORMAT, | |
608 _avg_major_pause->average(), gc_pause_goal_sec(), | |
609 *desired_promo_size_ptr, *desired_eden_size_ptr, | |
610 promo_heap_delta, eden_heap_delta); | |
611 } | |
612 } | |
613 | |
614 void PSAdaptiveSizePolicy::adjust_for_throughput(bool is_full_gc, | |
615 size_t* desired_promo_size_ptr, | |
616 size_t* desired_eden_size_ptr) { | |
617 | |
618 // Add some checks for a threshhold for a change. For example, | |
619 // a change less than the required alignment is probably not worth | |
620 // attempting. | |
621 if (is_full_gc) { | |
622 set_decide_at_full_gc(decide_at_full_gc_true); | |
623 } | |
624 | |
625 if ((gc_cost() + mutator_cost()) == 0.0) { | |
626 return; | |
627 } | |
628 | |
629 if (PrintAdaptiveSizePolicy && Verbose) { | |
630 gclog_or_tty->print("\nPSAdaptiveSizePolicy::adjust_for_throughput(" | |
631 "is_full: %d, promo: " SIZE_FORMAT ", cur_eden: " SIZE_FORMAT "): ", | |
632 is_full_gc, *desired_promo_size_ptr, *desired_eden_size_ptr); | |
633 gclog_or_tty->print_cr("mutator_cost %f major_gc_cost %f " | |
634 "minor_gc_cost %f", mutator_cost(), major_gc_cost(), minor_gc_cost()); | |
635 } | |
636 | |
637 // Tenured generation | |
638 if (is_full_gc) { | |
639 | |
640 // Calculate the change to use for the tenured gen. | |
641 size_t scaled_promo_heap_delta = 0; | |
642 // Can the increment to the generation be scaled? | |
643 if (gc_cost() >= 0.0 && major_gc_cost() >= 0.0) { | |
644 size_t promo_heap_delta = | |
645 promo_increment_with_supplement_aligned_up(*desired_promo_size_ptr); | |
646 double scale_by_ratio = major_gc_cost() / gc_cost(); | |
647 scaled_promo_heap_delta = | |
648 (size_t) (scale_by_ratio * (double) promo_heap_delta); | |
649 if (PrintAdaptiveSizePolicy && Verbose) { | |
650 gclog_or_tty->print_cr( | |
651 "Scaled tenured increment: " SIZE_FORMAT " by %f down to " | |
652 SIZE_FORMAT, | |
653 promo_heap_delta, scale_by_ratio, scaled_promo_heap_delta); | |
654 } | |
655 } else if (major_gc_cost() >= 0.0) { | |
656 // Scaling is not going to work. If the major gc time is the | |
657 // larger, give it a full increment. | |
658 if (major_gc_cost() >= minor_gc_cost()) { | |
659 scaled_promo_heap_delta = | |
660 promo_increment_with_supplement_aligned_up(*desired_promo_size_ptr); | |
661 } | |
662 } else { | |
663 // Don't expect to get here but it's ok if it does | |
664 // in the product build since the delta will be 0 | |
665 // and nothing will change. | |
666 assert(false, "Unexpected value for gc costs"); | |
667 } | |
668 | |
669 switch (AdaptiveSizeThroughPutPolicy) { | |
670 case 1: | |
671 // Early in the run the statistics might not be good. Until | |
672 // a specific number of collections have been, use the heuristic | |
673 // that a larger generation size means lower collection costs. | |
674 if (major_collection_estimator()->increment_will_decrease() || | |
675 (_old_gen_change_for_major_throughput | |
676 <= AdaptiveSizePolicyInitializingSteps)) { | |
677 // Increase tenured generation size to reduce major collection cost | |
678 if ((*desired_promo_size_ptr + scaled_promo_heap_delta) > | |
679 *desired_promo_size_ptr) { | |
680 *desired_promo_size_ptr = _promo_size + scaled_promo_heap_delta; | |
681 } | |
682 set_change_old_gen_for_throughput( | |
683 increase_old_gen_for_throughput_true); | |
684 _old_gen_change_for_major_throughput++; | |
685 } else { | |
686 // EXPERIMENTAL ADJUSTMENT | |
687 // Record that decreasing the old gen size would decrease | |
688 // the major collection cost but don't do it. | |
689 // *desired_promo_size_ptr = _promo_size - | |
690 // promo_decrement_aligned_down(*desired_promo_size_ptr); | |
691 set_change_old_gen_for_throughput( | |
692 decrease_old_gen_for_throughput_true); | |
693 } | |
694 | |
695 break; | |
696 default: | |
697 // Simplest strategy | |
698 if ((*desired_promo_size_ptr + scaled_promo_heap_delta) > | |
699 *desired_promo_size_ptr) { | |
700 *desired_promo_size_ptr = *desired_promo_size_ptr + | |
701 scaled_promo_heap_delta; | |
702 } | |
703 set_change_old_gen_for_throughput( | |
704 increase_old_gen_for_throughput_true); | |
705 _old_gen_change_for_major_throughput++; | |
706 } | |
707 | |
708 if (PrintAdaptiveSizePolicy && Verbose) { | |
709 gclog_or_tty->print_cr( | |
710 "adjusting tenured gen for throughput (avg %f goal %f). " | |
711 "desired_promo_size " SIZE_FORMAT " promo_delta " SIZE_FORMAT , | |
712 mutator_cost(), _throughput_goal, | |
713 *desired_promo_size_ptr, scaled_promo_heap_delta); | |
714 } | |
715 } | |
716 | |
717 // Young generation | |
718 size_t scaled_eden_heap_delta = 0; | |
719 // Can the increment to the generation be scaled? | |
720 if (gc_cost() >= 0.0 && minor_gc_cost() >= 0.0) { | |
721 size_t eden_heap_delta = | |
722 eden_increment_with_supplement_aligned_up(*desired_eden_size_ptr); | |
723 double scale_by_ratio = minor_gc_cost() / gc_cost(); | |
724 assert(scale_by_ratio <= 1.0 && scale_by_ratio >= 0.0, "Scaling is wrong"); | |
725 scaled_eden_heap_delta = | |
726 (size_t) (scale_by_ratio * (double) eden_heap_delta); | |
727 if (PrintAdaptiveSizePolicy && Verbose) { | |
728 gclog_or_tty->print_cr( | |
729 "Scaled eden increment: " SIZE_FORMAT " by %f down to " | |
730 SIZE_FORMAT, | |
731 eden_heap_delta, scale_by_ratio, scaled_eden_heap_delta); | |
732 } | |
733 } else if (minor_gc_cost() >= 0.0) { | |
734 // Scaling is not going to work. If the minor gc time is the | |
735 // larger, give it a full increment. | |
736 if (minor_gc_cost() > major_gc_cost()) { | |
737 scaled_eden_heap_delta = | |
738 eden_increment_with_supplement_aligned_up(*desired_eden_size_ptr); | |
739 } | |
740 } else { | |
741 // Don't expect to get here but it's ok if it does | |
742 // in the product build since the delta will be 0 | |
743 // and nothing will change. | |
744 assert(false, "Unexpected value for gc costs"); | |
745 } | |
746 | |
747 // Use a heuristic for some number of collections to give | |
748 // the averages time to settle down. | |
749 switch (AdaptiveSizeThroughPutPolicy) { | |
750 case 1: | |
751 if (minor_collection_estimator()->increment_will_decrease() || | |
752 (_young_gen_change_for_minor_throughput | |
753 <= AdaptiveSizePolicyInitializingSteps)) { | |
754 // Expand young generation size to reduce frequency of | |
755 // of collections. | |
756 if ((*desired_eden_size_ptr + scaled_eden_heap_delta) > | |
757 *desired_eden_size_ptr) { | |
758 *desired_eden_size_ptr = | |
759 *desired_eden_size_ptr + scaled_eden_heap_delta; | |
760 } | |
761 set_change_young_gen_for_throughput( | |
762 increase_young_gen_for_througput_true); | |
763 _young_gen_change_for_minor_throughput++; | |
764 } else { | |
765 // EXPERIMENTAL ADJUSTMENT | |
766 // Record that decreasing the young gen size would decrease | |
767 // the minor collection cost but don't do it. | |
768 // *desired_eden_size_ptr = _eden_size - | |
769 // eden_decrement_aligned_down(*desired_eden_size_ptr); | |
770 set_change_young_gen_for_throughput( | |
771 decrease_young_gen_for_througput_true); | |
772 } | |
773 break; | |
774 default: | |
775 if ((*desired_eden_size_ptr + scaled_eden_heap_delta) > | |
776 *desired_eden_size_ptr) { | |
777 *desired_eden_size_ptr = | |
778 *desired_eden_size_ptr + scaled_eden_heap_delta; | |
779 } | |
780 set_change_young_gen_for_throughput( | |
781 increase_young_gen_for_througput_true); | |
782 _young_gen_change_for_minor_throughput++; | |
783 } | |
784 | |
785 if (PrintAdaptiveSizePolicy && Verbose) { | |
786 gclog_or_tty->print_cr( | |
787 "adjusting eden for throughput (avg %f goal %f). desired_eden_size " | |
788 SIZE_FORMAT " eden delta " SIZE_FORMAT "\n", | |
789 mutator_cost(), _throughput_goal, | |
790 *desired_eden_size_ptr, scaled_eden_heap_delta); | |
791 } | |
792 } | |
793 | |
794 size_t PSAdaptiveSizePolicy::adjust_promo_for_footprint( | |
795 size_t desired_promo_size, size_t desired_sum) { | |
796 assert(desired_promo_size <= desired_sum, "Inconsistent parameters"); | |
797 set_decrease_for_footprint(decrease_old_gen_for_footprint_true); | |
798 | |
799 size_t change = promo_decrement(desired_promo_size); | |
800 change = scale_down(change, desired_promo_size, desired_sum); | |
801 | |
802 size_t reduced_size = desired_promo_size - change; | |
803 | |
804 if (PrintAdaptiveSizePolicy && Verbose) { | |
805 gclog_or_tty->print_cr( | |
806 "AdaptiveSizePolicy::compute_generation_free_space " | |
807 "adjusting tenured gen for footprint. " | |
808 "starting promo size " SIZE_FORMAT | |
809 " reduced promo size " SIZE_FORMAT, | |
810 " promo delta " SIZE_FORMAT, | |
811 desired_promo_size, reduced_size, change ); | |
812 } | |
813 | |
814 assert(reduced_size <= desired_promo_size, "Inconsistent result"); | |
815 return reduced_size; | |
816 } | |
817 | |
818 size_t PSAdaptiveSizePolicy::adjust_eden_for_footprint( | |
819 size_t desired_eden_size, size_t desired_sum) { | |
820 assert(desired_eden_size <= desired_sum, "Inconsistent parameters"); | |
821 set_decrease_for_footprint(decrease_young_gen_for_footprint_true); | |
822 | |
823 size_t change = eden_decrement(desired_eden_size); | |
824 change = scale_down(change, desired_eden_size, desired_sum); | |
825 | |
826 size_t reduced_size = desired_eden_size - change; | |
827 | |
828 if (PrintAdaptiveSizePolicy && Verbose) { | |
829 gclog_or_tty->print_cr( | |
830 "AdaptiveSizePolicy::compute_generation_free_space " | |
831 "adjusting eden for footprint. " | |
832 " starting eden size " SIZE_FORMAT | |
833 " reduced eden size " SIZE_FORMAT | |
834 " eden delta " SIZE_FORMAT, | |
835 desired_eden_size, reduced_size, change); | |
836 } | |
837 | |
838 assert(reduced_size <= desired_eden_size, "Inconsistent result"); | |
839 return reduced_size; | |
840 } | |
841 | |
842 // Scale down "change" by the factor | |
843 // part / total | |
844 // Don't align the results. | |
845 | |
846 size_t PSAdaptiveSizePolicy::scale_down(size_t change, | |
847 double part, | |
848 double total) { | |
849 assert(part <= total, "Inconsistent input"); | |
850 size_t reduced_change = change; | |
851 if (total > 0) { | |
852 double fraction = part / total; | |
853 reduced_change = (size_t) (fraction * (double) change); | |
854 } | |
855 assert(reduced_change <= change, "Inconsistent result"); | |
856 return reduced_change; | |
857 } | |
858 | |
859 size_t PSAdaptiveSizePolicy::eden_increment(size_t cur_eden, | |
860 uint percent_change) { | |
861 size_t eden_heap_delta; | |
862 eden_heap_delta = cur_eden / 100 * percent_change; | |
863 return eden_heap_delta; | |
864 } | |
865 | |
866 size_t PSAdaptiveSizePolicy::eden_increment(size_t cur_eden) { | |
867 return eden_increment(cur_eden, YoungGenerationSizeIncrement); | |
868 } | |
869 | |
870 size_t PSAdaptiveSizePolicy::eden_increment_aligned_up(size_t cur_eden) { | |
871 size_t result = eden_increment(cur_eden, YoungGenerationSizeIncrement); | |
872 return align_size_up(result, _intra_generation_alignment); | |
873 } | |
874 | |
875 size_t PSAdaptiveSizePolicy::eden_increment_aligned_down(size_t cur_eden) { | |
876 size_t result = eden_increment(cur_eden); | |
877 return align_size_down(result, _intra_generation_alignment); | |
878 } | |
879 | |
880 size_t PSAdaptiveSizePolicy::eden_increment_with_supplement_aligned_up( | |
881 size_t cur_eden) { | |
882 size_t result = eden_increment(cur_eden, | |
883 YoungGenerationSizeIncrement + _young_gen_size_increment_supplement); | |
884 return align_size_up(result, _intra_generation_alignment); | |
885 } | |
886 | |
887 size_t PSAdaptiveSizePolicy::eden_decrement_aligned_down(size_t cur_eden) { | |
888 size_t eden_heap_delta = eden_decrement(cur_eden); | |
889 return align_size_down(eden_heap_delta, _intra_generation_alignment); | |
890 } | |
891 | |
892 size_t PSAdaptiveSizePolicy::eden_decrement(size_t cur_eden) { | |
893 size_t eden_heap_delta = eden_increment(cur_eden) / | |
894 AdaptiveSizeDecrementScaleFactor; | |
895 return eden_heap_delta; | |
896 } | |
897 | |
898 size_t PSAdaptiveSizePolicy::promo_increment(size_t cur_promo, | |
899 uint percent_change) { | |
900 size_t promo_heap_delta; | |
901 promo_heap_delta = cur_promo / 100 * percent_change; | |
902 return promo_heap_delta; | |
903 } | |
904 | |
905 size_t PSAdaptiveSizePolicy::promo_increment(size_t cur_promo) { | |
906 return promo_increment(cur_promo, TenuredGenerationSizeIncrement); | |
907 } | |
908 | |
909 size_t PSAdaptiveSizePolicy::promo_increment_aligned_up(size_t cur_promo) { | |
910 size_t result = promo_increment(cur_promo, TenuredGenerationSizeIncrement); | |
911 return align_size_up(result, _intra_generation_alignment); | |
912 } | |
913 | |
914 size_t PSAdaptiveSizePolicy::promo_increment_aligned_down(size_t cur_promo) { | |
915 size_t result = promo_increment(cur_promo, TenuredGenerationSizeIncrement); | |
916 return align_size_down(result, _intra_generation_alignment); | |
917 } | |
918 | |
919 size_t PSAdaptiveSizePolicy::promo_increment_with_supplement_aligned_up( | |
920 size_t cur_promo) { | |
921 size_t result = promo_increment(cur_promo, | |
922 TenuredGenerationSizeIncrement + _old_gen_size_increment_supplement); | |
923 return align_size_up(result, _intra_generation_alignment); | |
924 } | |
925 | |
926 size_t PSAdaptiveSizePolicy::promo_decrement_aligned_down(size_t cur_promo) { | |
927 size_t promo_heap_delta = promo_decrement(cur_promo); | |
928 return align_size_down(promo_heap_delta, _intra_generation_alignment); | |
929 } | |
930 | |
931 size_t PSAdaptiveSizePolicy::promo_decrement(size_t cur_promo) { | |
932 size_t promo_heap_delta = promo_increment(cur_promo); | |
933 promo_heap_delta = promo_heap_delta / AdaptiveSizeDecrementScaleFactor; | |
934 return promo_heap_delta; | |
935 } | |
936 | |
937 int PSAdaptiveSizePolicy::compute_survivor_space_size_and_threshold( | |
938 bool is_survivor_overflow, | |
939 int tenuring_threshold, | |
940 size_t survivor_limit) { | |
941 assert(survivor_limit >= _intra_generation_alignment, | |
942 "survivor_limit too small"); | |
943 assert((size_t)align_size_down(survivor_limit, _intra_generation_alignment) | |
944 == survivor_limit, "survivor_limit not aligned"); | |
945 | |
946 // This method is called even if the tenuring threshold and survivor | |
947 // spaces are not adjusted so that the averages are sampled above. | |
948 if (!UsePSAdaptiveSurvivorSizePolicy || | |
949 !young_gen_policy_is_ready()) { | |
950 return tenuring_threshold; | |
951 } | |
952 | |
953 // We'll decide whether to increase or decrease the tenuring | |
954 // threshold based partly on the newly computed survivor size | |
955 // (if we hit the maximum limit allowed, we'll always choose to | |
956 // decrement the threshold). | |
957 bool incr_tenuring_threshold = false; | |
958 bool decr_tenuring_threshold = false; | |
959 | |
960 set_decrement_tenuring_threshold_for_gc_cost(false); | |
961 set_increment_tenuring_threshold_for_gc_cost(false); | |
962 set_decrement_tenuring_threshold_for_survivor_limit(false); | |
963 | |
964 if (!is_survivor_overflow) { | |
965 // Keep running averages on how much survived | |
966 | |
967 // We use the tenuring threshold to equalize the cost of major | |
968 // and minor collections. | |
969 // ThresholdTolerance is used to indicate how sensitive the | |
970 // tenuring threshold is to differences in cost betweent the | |
971 // collection types. | |
972 | |
973 // Get the times of interest. This involves a little work, so | |
974 // we cache the values here. | |
975 const double major_cost = major_gc_cost(); | |
976 const double minor_cost = minor_gc_cost(); | |
977 | |
978 if (minor_cost > major_cost * _threshold_tolerance_percent) { | |
979 // Minor times are getting too long; lower the threshold so | |
980 // less survives and more is promoted. | |
981 decr_tenuring_threshold = true; | |
982 set_decrement_tenuring_threshold_for_gc_cost(true); | |
983 } else if (major_cost > minor_cost * _threshold_tolerance_percent) { | |
984 // Major times are too long, so we want less promotion. | |
985 incr_tenuring_threshold = true; | |
986 set_increment_tenuring_threshold_for_gc_cost(true); | |
987 } | |
988 | |
989 } else { | |
990 // Survivor space overflow occurred, so promoted and survived are | |
991 // not accurate. We'll make our best guess by combining survived | |
992 // and promoted and count them as survivors. | |
993 // | |
994 // We'll lower the tenuring threshold to see if we can correct | |
995 // things. Also, set the survivor size conservatively. We're | |
996 // trying to avoid many overflows from occurring if defnew size | |
997 // is just too small. | |
998 | |
999 decr_tenuring_threshold = true; | |
1000 } | |
1001 | |
1002 // The padded average also maintains a deviation from the average; | |
1003 // we use this to see how good of an estimate we have of what survived. | |
1004 // We're trying to pad the survivor size as little as possible without | |
1005 // overflowing the survivor spaces. | |
1006 size_t target_size = align_size_up((size_t)_avg_survived->padded_average(), | |
1007 _intra_generation_alignment); | |
1008 target_size = MAX2(target_size, _intra_generation_alignment); | |
1009 | |
1010 if (target_size > survivor_limit) { | |
1011 // Target size is bigger than we can handle. Let's also reduce | |
1012 // the tenuring threshold. | |
1013 target_size = survivor_limit; | |
1014 decr_tenuring_threshold = true; | |
1015 set_decrement_tenuring_threshold_for_survivor_limit(true); | |
1016 } | |
1017 | |
1018 // Finally, increment or decrement the tenuring threshold, as decided above. | |
1019 // We test for decrementing first, as we might have hit the target size | |
1020 // limit. | |
1021 if (decr_tenuring_threshold && !(AlwaysTenure || NeverTenure)) { | |
1022 if (tenuring_threshold > 1) { | |
1023 tenuring_threshold--; | |
1024 } | |
1025 } else if (incr_tenuring_threshold && !(AlwaysTenure || NeverTenure)) { | |
1026 if (tenuring_threshold < MaxTenuringThreshold) { | |
1027 tenuring_threshold++; | |
1028 } | |
1029 } | |
1030 | |
1031 // We keep a running average of the amount promoted which is used | |
1032 // to decide when we should collect the old generation (when | |
1033 // the amount of old gen free space is less than what we expect to | |
1034 // promote). | |
1035 | |
1036 if (PrintAdaptiveSizePolicy) { | |
1037 // A little more detail if Verbose is on | |
1038 if (Verbose) { | |
1039 gclog_or_tty->print( " avg_survived: %f" | |
1040 " avg_deviation: %f", | |
1041 _avg_survived->average(), | |
1042 _avg_survived->deviation()); | |
1043 } | |
1044 | |
1045 gclog_or_tty->print( " avg_survived_padded_avg: %f", | |
1046 _avg_survived->padded_average()); | |
1047 | |
1048 if (Verbose) { | |
1049 gclog_or_tty->print( " avg_promoted_avg: %f" | |
1050 " avg_promoted_dev: %f", | |
1051 avg_promoted()->average(), | |
1052 avg_promoted()->deviation()); | |
1053 } | |
1054 | |
1055 gclog_or_tty->print( " avg_promoted_padded_avg: %f" | |
1056 " avg_pretenured_padded_avg: %f" | |
1057 " tenuring_thresh: %d" | |
1058 " target_size: " SIZE_FORMAT, | |
1059 avg_promoted()->padded_average(), | |
1060 _avg_pretenured->padded_average(), | |
1061 tenuring_threshold, target_size); | |
1062 tty->cr(); | |
1063 } | |
1064 | |
1065 set_survivor_size(target_size); | |
1066 | |
1067 return tenuring_threshold; | |
1068 } | |
1069 | |
1070 void PSAdaptiveSizePolicy::update_averages(bool is_survivor_overflow, | |
1071 size_t survived, | |
1072 size_t promoted) { | |
1073 // Update averages | |
1074 if (!is_survivor_overflow) { | |
1075 // Keep running averages on how much survived | |
1076 _avg_survived->sample(survived); | |
1077 } else { | |
1078 size_t survived_guess = survived + promoted; | |
1079 _avg_survived->sample(survived_guess); | |
1080 } | |
1081 avg_promoted()->sample(promoted + _avg_pretenured->padded_average()); | |
1082 | |
1083 if (PrintAdaptiveSizePolicy) { | |
1084 gclog_or_tty->print( | |
1085 "AdaptiveSizePolicy::compute_survivor_space_size_and_thresh:" | |
1086 " survived: " SIZE_FORMAT | |
1087 " promoted: " SIZE_FORMAT | |
1088 " overflow: %s", | |
1089 survived, promoted, is_survivor_overflow ? "true" : "false"); | |
1090 } | |
1091 } | |
1092 | |
1093 bool PSAdaptiveSizePolicy::print_adaptive_size_policy_on(outputStream* st) | |
1094 const { | |
1095 | |
1096 if (!UseAdaptiveSizePolicy) return false; | |
1097 | |
1098 return AdaptiveSizePolicy::print_adaptive_size_policy_on( | |
1099 st, | |
1100 PSScavenge::tenuring_threshold()); | |
1101 } |