Sat, 23 Nov 2013 12:25:13 +0100
8028128: Add a type safe alternative for working with counter based data
Reviewed-by: dholmes, egahlin
duke@435 | 1 | /* |
tamao@5120 | 2 | * Copyright (c) 2002, 2013, Oracle and/or its affiliates. All rights reserved. |
duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@435 | 4 | * |
duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
duke@435 | 7 | * published by the Free Software Foundation. |
duke@435 | 8 | * |
duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@435 | 13 | * accompanied this code). |
duke@435 | 14 | * |
duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@435 | 18 | * |
trims@1907 | 19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
trims@1907 | 20 | * or visit www.oracle.com if you need additional information or have any |
trims@1907 | 21 | * questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
stefank@2314 | 25 | #include "precompiled.hpp" |
stefank@2314 | 26 | #include "gc_implementation/parallelScavenge/psAdaptiveSizePolicy.hpp" |
stefank@2314 | 27 | #include "gc_implementation/parallelScavenge/psGCAdaptivePolicyCounters.hpp" |
stefank@2314 | 28 | #include "gc_implementation/parallelScavenge/psScavenge.hpp" |
stefank@2314 | 29 | #include "gc_implementation/shared/gcPolicyCounters.hpp" |
stefank@2314 | 30 | #include "gc_interface/gcCause.hpp" |
stefank@2314 | 31 | #include "memory/collectorPolicy.hpp" |
stefank@2314 | 32 | #include "runtime/timer.hpp" |
stefank@2314 | 33 | #include "utilities/top.hpp" |
duke@435 | 34 | |
duke@435 | 35 | #include <math.h> |
duke@435 | 36 | |
duke@435 | 37 | PSAdaptiveSizePolicy::PSAdaptiveSizePolicy(size_t init_eden_size, |
duke@435 | 38 | size_t init_promo_size, |
duke@435 | 39 | size_t init_survivor_size, |
jwilhelm@6085 | 40 | size_t space_alignment, |
duke@435 | 41 | double gc_pause_goal_sec, |
duke@435 | 42 | double gc_minor_pause_goal_sec, |
duke@435 | 43 | uint gc_cost_ratio) : |
duke@435 | 44 | AdaptiveSizePolicy(init_eden_size, |
duke@435 | 45 | init_promo_size, |
duke@435 | 46 | init_survivor_size, |
duke@435 | 47 | gc_pause_goal_sec, |
duke@435 | 48 | gc_cost_ratio), |
jwilhelm@6084 | 49 | _collection_cost_margin_fraction(AdaptiveSizePolicyCollectionCostMargin / 100.0), |
jwilhelm@6085 | 50 | _space_alignment(space_alignment), |
duke@435 | 51 | _live_at_last_full_gc(init_promo_size), |
duke@435 | 52 | _gc_minor_pause_goal_sec(gc_minor_pause_goal_sec), |
duke@435 | 53 | _latest_major_mutator_interval_seconds(0), |
duke@435 | 54 | _young_gen_change_for_major_pause_count(0) |
duke@435 | 55 | { |
duke@435 | 56 | // Sizing policy statistics |
duke@435 | 57 | _avg_major_pause = |
duke@435 | 58 | new AdaptivePaddedAverage(AdaptiveTimeWeight, PausePadding); |
duke@435 | 59 | _avg_minor_interval = new AdaptiveWeightedAverage(AdaptiveTimeWeight); |
duke@435 | 60 | _avg_major_interval = new AdaptiveWeightedAverage(AdaptiveTimeWeight); |
duke@435 | 61 | |
duke@435 | 62 | _avg_base_footprint = new AdaptiveWeightedAverage(AdaptiveSizePolicyWeight); |
duke@435 | 63 | _major_pause_old_estimator = |
duke@435 | 64 | new LinearLeastSquareFit(AdaptiveSizePolicyWeight); |
duke@435 | 65 | _major_pause_young_estimator = |
duke@435 | 66 | new LinearLeastSquareFit(AdaptiveSizePolicyWeight); |
duke@435 | 67 | _major_collection_estimator = |
duke@435 | 68 | new LinearLeastSquareFit(AdaptiveSizePolicyWeight); |
duke@435 | 69 | |
duke@435 | 70 | _young_gen_size_increment_supplement = YoungGenerationSizeSupplement; |
duke@435 | 71 | _old_gen_size_increment_supplement = TenuredGenerationSizeSupplement; |
duke@435 | 72 | |
duke@435 | 73 | // Start the timers |
duke@435 | 74 | _major_timer.start(); |
duke@435 | 75 | |
duke@435 | 76 | _old_gen_policy_is_ready = false; |
duke@435 | 77 | } |
duke@435 | 78 | |
duke@435 | 79 | void PSAdaptiveSizePolicy::major_collection_begin() { |
duke@435 | 80 | // Update the interval time |
duke@435 | 81 | _major_timer.stop(); |
duke@435 | 82 | // Save most recent collection time |
duke@435 | 83 | _latest_major_mutator_interval_seconds = _major_timer.seconds(); |
duke@435 | 84 | _major_timer.reset(); |
duke@435 | 85 | _major_timer.start(); |
duke@435 | 86 | } |
duke@435 | 87 | |
duke@435 | 88 | void PSAdaptiveSizePolicy::update_minor_pause_old_estimator( |
duke@435 | 89 | double minor_pause_in_ms) { |
duke@435 | 90 | double promo_size_in_mbytes = ((double)_promo_size)/((double)M); |
duke@435 | 91 | _minor_pause_old_estimator->update(promo_size_in_mbytes, |
duke@435 | 92 | minor_pause_in_ms); |
duke@435 | 93 | } |
duke@435 | 94 | |
duke@435 | 95 | void PSAdaptiveSizePolicy::major_collection_end(size_t amount_live, |
duke@435 | 96 | GCCause::Cause gc_cause) { |
duke@435 | 97 | // Update the pause time. |
duke@435 | 98 | _major_timer.stop(); |
duke@435 | 99 | |
duke@435 | 100 | if (gc_cause != GCCause::_java_lang_system_gc || |
duke@435 | 101 | UseAdaptiveSizePolicyWithSystemGC) { |
duke@435 | 102 | double major_pause_in_seconds = _major_timer.seconds(); |
duke@435 | 103 | double major_pause_in_ms = major_pause_in_seconds * MILLIUNITS; |
duke@435 | 104 | |
duke@435 | 105 | // Sample for performance counter |
duke@435 | 106 | _avg_major_pause->sample(major_pause_in_seconds); |
duke@435 | 107 | |
duke@435 | 108 | // Cost of collection (unit-less) |
duke@435 | 109 | double collection_cost = 0.0; |
duke@435 | 110 | if ((_latest_major_mutator_interval_seconds > 0.0) && |
duke@435 | 111 | (major_pause_in_seconds > 0.0)) { |
duke@435 | 112 | double interval_in_seconds = |
duke@435 | 113 | _latest_major_mutator_interval_seconds + major_pause_in_seconds; |
duke@435 | 114 | collection_cost = |
duke@435 | 115 | major_pause_in_seconds / interval_in_seconds; |
duke@435 | 116 | avg_major_gc_cost()->sample(collection_cost); |
duke@435 | 117 | |
duke@435 | 118 | // Sample for performance counter |
duke@435 | 119 | _avg_major_interval->sample(interval_in_seconds); |
duke@435 | 120 | } |
duke@435 | 121 | |
duke@435 | 122 | // Calculate variables used to estimate pause time vs. gen sizes |
duke@435 | 123 | double eden_size_in_mbytes = ((double)_eden_size)/((double)M); |
duke@435 | 124 | double promo_size_in_mbytes = ((double)_promo_size)/((double)M); |
duke@435 | 125 | _major_pause_old_estimator->update(promo_size_in_mbytes, |
duke@435 | 126 | major_pause_in_ms); |
duke@435 | 127 | _major_pause_young_estimator->update(eden_size_in_mbytes, |
duke@435 | 128 | major_pause_in_ms); |
duke@435 | 129 | |
duke@435 | 130 | if (PrintAdaptiveSizePolicy && Verbose) { |
duke@435 | 131 | gclog_or_tty->print("psAdaptiveSizePolicy::major_collection_end: " |
duke@435 | 132 | "major gc cost: %f average: %f", collection_cost, |
duke@435 | 133 | avg_major_gc_cost()->average()); |
duke@435 | 134 | gclog_or_tty->print_cr(" major pause: %f major period %f", |
duke@435 | 135 | major_pause_in_ms, |
duke@435 | 136 | _latest_major_mutator_interval_seconds * MILLIUNITS); |
duke@435 | 137 | } |
duke@435 | 138 | |
duke@435 | 139 | // Calculate variable used to estimate collection cost vs. gen sizes |
duke@435 | 140 | assert(collection_cost >= 0.0, "Expected to be non-negative"); |
duke@435 | 141 | _major_collection_estimator->update(promo_size_in_mbytes, |
duke@435 | 142 | collection_cost); |
duke@435 | 143 | } |
duke@435 | 144 | |
duke@435 | 145 | // Update the amount live at the end of a full GC |
duke@435 | 146 | _live_at_last_full_gc = amount_live; |
duke@435 | 147 | |
duke@435 | 148 | // The policy does not have enough data until at least some major collections |
duke@435 | 149 | // have been done. |
duke@435 | 150 | if (_avg_major_pause->count() >= AdaptiveSizePolicyReadyThreshold) { |
duke@435 | 151 | _old_gen_policy_is_ready = true; |
duke@435 | 152 | } |
duke@435 | 153 | |
duke@435 | 154 | // Interval times use this timer to measure the interval that |
duke@435 | 155 | // the mutator runs. Reset after the GC pause has been measured. |
duke@435 | 156 | _major_timer.reset(); |
duke@435 | 157 | _major_timer.start(); |
duke@435 | 158 | } |
duke@435 | 159 | |
duke@435 | 160 | // If the remaining free space in the old generation is less that |
duke@435 | 161 | // that expected to be needed by the next collection, do a full |
duke@435 | 162 | // collection now. |
duke@435 | 163 | bool PSAdaptiveSizePolicy::should_full_GC(size_t old_free_in_bytes) { |
duke@435 | 164 | |
duke@435 | 165 | // A similar test is done in the scavenge's should_attempt_scavenge(). If |
duke@435 | 166 | // this is changed, decide if that test should also be changed. |
duke@435 | 167 | bool result = padded_average_promoted_in_bytes() > (float) old_free_in_bytes; |
duke@435 | 168 | if (PrintGCDetails && Verbose) { |
duke@435 | 169 | if (result) { |
duke@435 | 170 | gclog_or_tty->print(" full after scavenge: "); |
duke@435 | 171 | } else { |
duke@435 | 172 | gclog_or_tty->print(" no full after scavenge: "); |
duke@435 | 173 | } |
duke@435 | 174 | gclog_or_tty->print_cr(" average_promoted " SIZE_FORMAT |
duke@435 | 175 | " padded_average_promoted " SIZE_FORMAT |
duke@435 | 176 | " free in old gen " SIZE_FORMAT, |
duke@435 | 177 | (size_t) average_promoted_in_bytes(), |
duke@435 | 178 | (size_t) padded_average_promoted_in_bytes(), |
duke@435 | 179 | old_free_in_bytes); |
duke@435 | 180 | } |
duke@435 | 181 | return result; |
duke@435 | 182 | } |
duke@435 | 183 | |
duke@435 | 184 | void PSAdaptiveSizePolicy::clear_generation_free_space_flags() { |
duke@435 | 185 | |
duke@435 | 186 | AdaptiveSizePolicy::clear_generation_free_space_flags(); |
duke@435 | 187 | |
duke@435 | 188 | set_change_old_gen_for_min_pauses(0); |
duke@435 | 189 | |
duke@435 | 190 | set_change_young_gen_for_maj_pauses(0); |
duke@435 | 191 | } |
duke@435 | 192 | |
duke@435 | 193 | // If this is not a full GC, only test and modify the young generation. |
duke@435 | 194 | |
tamao@5192 | 195 | void PSAdaptiveSizePolicy::compute_generations_free_space( |
jmasa@1822 | 196 | size_t young_live, |
jmasa@1822 | 197 | size_t eden_live, |
jmasa@1822 | 198 | size_t old_live, |
jmasa@1822 | 199 | size_t cur_eden, |
jmasa@1822 | 200 | size_t max_old_gen_size, |
jmasa@1822 | 201 | size_t max_eden_size, |
tamao@5120 | 202 | bool is_full_gc) { |
tamao@5120 | 203 | compute_eden_space_size(young_live, |
tamao@5120 | 204 | eden_live, |
tamao@5120 | 205 | cur_eden, |
tamao@5120 | 206 | max_eden_size, |
tamao@5120 | 207 | is_full_gc); |
tamao@5120 | 208 | |
tamao@5120 | 209 | compute_old_gen_free_space(old_live, |
tamao@5120 | 210 | cur_eden, |
tamao@5120 | 211 | max_old_gen_size, |
tamao@5120 | 212 | is_full_gc); |
tamao@5120 | 213 | } |
tamao@5120 | 214 | |
tamao@5120 | 215 | void PSAdaptiveSizePolicy::compute_eden_space_size( |
tamao@5120 | 216 | size_t young_live, |
tamao@5120 | 217 | size_t eden_live, |
tamao@5120 | 218 | size_t cur_eden, |
tamao@5120 | 219 | size_t max_eden_size, |
tamao@5120 | 220 | bool is_full_gc) { |
duke@435 | 221 | |
duke@435 | 222 | // Update statistics |
duke@435 | 223 | // Time statistics are updated as we go, update footprint stats here |
coleenp@4037 | 224 | _avg_base_footprint->sample(BaseFootPrintEstimate); |
duke@435 | 225 | avg_young_live()->sample(young_live); |
duke@435 | 226 | avg_eden_live()->sample(eden_live); |
tamao@5120 | 227 | |
tamao@5120 | 228 | // This code used to return if the policy was not ready , i.e., |
tamao@5120 | 229 | // policy_is_ready() returning false. The intent was that |
tamao@5120 | 230 | // decisions below needed major collection times and so could |
tamao@5120 | 231 | // not be made before two major collections. A consequence was |
tamao@5120 | 232 | // adjustments to the young generation were not done until after |
tamao@5120 | 233 | // two major collections even if the minor collections times |
tamao@5120 | 234 | // exceeded the requested goals. Now let the young generation |
tamao@5120 | 235 | // adjust for the minor collection times. Major collection times |
tamao@5120 | 236 | // will be zero for the first collection and will naturally be |
tamao@5120 | 237 | // ignored. Tenured generation adjustments are only made at the |
tamao@5120 | 238 | // full collections so until the second major collection has |
tamao@5120 | 239 | // been reached, no tenured generation adjustments will be made. |
tamao@5120 | 240 | |
tamao@5120 | 241 | // Until we know better, desired promotion size uses the last calculation |
tamao@5120 | 242 | size_t desired_promo_size = _promo_size; |
tamao@5120 | 243 | |
tamao@5120 | 244 | // Start eden at the current value. The desired value that is stored |
tamao@5120 | 245 | // in _eden_size is not bounded by constraints of the heap and can |
tamao@5120 | 246 | // run away. |
tamao@5120 | 247 | // |
tamao@5120 | 248 | // As expected setting desired_eden_size to the current |
tamao@5120 | 249 | // value of desired_eden_size as a starting point |
tamao@5120 | 250 | // caused desired_eden_size to grow way too large and caused |
tamao@5120 | 251 | // an overflow down stream. It may have improved performance in |
tamao@5120 | 252 | // some case but is dangerous. |
tamao@5120 | 253 | size_t desired_eden_size = cur_eden; |
tamao@5120 | 254 | |
tamao@5120 | 255 | // Cache some values. There's a bit of work getting these, so |
tamao@5120 | 256 | // we might save a little time. |
tamao@5120 | 257 | const double major_cost = major_gc_cost(); |
tamao@5120 | 258 | const double minor_cost = minor_gc_cost(); |
tamao@5120 | 259 | |
tamao@5120 | 260 | // This method sets the desired eden size. That plus the |
tamao@5120 | 261 | // desired survivor space sizes sets the desired young generation |
tamao@5120 | 262 | // size. This methods does not know what the desired survivor |
tamao@5120 | 263 | // size is but expects that other policy will attempt to make |
tamao@5120 | 264 | // the survivor sizes compatible with the live data in the |
tamao@5120 | 265 | // young generation. This limit is an estimate of the space left |
tamao@5120 | 266 | // in the young generation after the survivor spaces have been |
tamao@5120 | 267 | // subtracted out. |
tamao@5120 | 268 | size_t eden_limit = max_eden_size; |
tamao@5120 | 269 | |
tamao@5120 | 270 | const double gc_cost_limit = GCTimeLimit/100.0; |
tamao@5120 | 271 | |
tamao@5120 | 272 | // Which way should we go? |
tamao@5120 | 273 | // if pause requirement is not met |
tamao@5120 | 274 | // adjust size of any generation with average paus exceeding |
tamao@5120 | 275 | // the pause limit. Adjust one pause at a time (the larger) |
tamao@5120 | 276 | // and only make adjustments for the major pause at full collections. |
tamao@5120 | 277 | // else if throughput requirement not met |
tamao@5120 | 278 | // adjust the size of the generation with larger gc time. Only |
tamao@5120 | 279 | // adjust one generation at a time. |
tamao@5120 | 280 | // else |
tamao@5120 | 281 | // adjust down the total heap size. Adjust down the larger of the |
tamao@5120 | 282 | // generations. |
tamao@5120 | 283 | |
tamao@5120 | 284 | // Add some checks for a threshold for a change. For example, |
tamao@5120 | 285 | // a change less than the necessary alignment is probably not worth |
tamao@5120 | 286 | // attempting. |
tamao@5120 | 287 | |
tamao@5120 | 288 | |
tamao@5120 | 289 | if ((_avg_minor_pause->padded_average() > gc_pause_goal_sec()) || |
tamao@5120 | 290 | (_avg_major_pause->padded_average() > gc_pause_goal_sec())) { |
tamao@5120 | 291 | // |
tamao@5120 | 292 | // Check pauses |
tamao@5120 | 293 | // |
tamao@5120 | 294 | // Make changes only to affect one of the pauses (the larger) |
tamao@5120 | 295 | // at a time. |
tamao@5120 | 296 | adjust_eden_for_pause_time(is_full_gc, &desired_promo_size, &desired_eden_size); |
tamao@5120 | 297 | |
tamao@5120 | 298 | } else if (_avg_minor_pause->padded_average() > gc_minor_pause_goal_sec()) { |
tamao@5120 | 299 | // Adjust only for the minor pause time goal |
tamao@5120 | 300 | adjust_eden_for_minor_pause_time(is_full_gc, &desired_eden_size); |
tamao@5120 | 301 | |
tamao@5120 | 302 | } else if(adjusted_mutator_cost() < _throughput_goal) { |
tamao@5120 | 303 | // This branch used to require that (mutator_cost() > 0.0 in 1.4.2. |
tamao@5120 | 304 | // This sometimes resulted in skipping to the minimize footprint |
tamao@5120 | 305 | // code. Change this to try and reduce GC time if mutator time is |
tamao@5120 | 306 | // negative for whatever reason. Or for future consideration, |
tamao@5120 | 307 | // bail out of the code if mutator time is negative. |
tamao@5120 | 308 | // |
tamao@5120 | 309 | // Throughput |
tamao@5120 | 310 | // |
tamao@5120 | 311 | assert(major_cost >= 0.0, "major cost is < 0.0"); |
tamao@5120 | 312 | assert(minor_cost >= 0.0, "minor cost is < 0.0"); |
tamao@5120 | 313 | // Try to reduce the GC times. |
tamao@5120 | 314 | adjust_eden_for_throughput(is_full_gc, &desired_eden_size); |
tamao@5120 | 315 | |
tamao@5120 | 316 | } else { |
tamao@5120 | 317 | |
tamao@5120 | 318 | // Be conservative about reducing the footprint. |
tamao@5120 | 319 | // Do a minimum number of major collections first. |
tamao@5120 | 320 | // Have reasonable averages for major and minor collections costs. |
tamao@5120 | 321 | if (UseAdaptiveSizePolicyFootprintGoal && |
tamao@5120 | 322 | young_gen_policy_is_ready() && |
tamao@5120 | 323 | avg_major_gc_cost()->average() >= 0.0 && |
tamao@5120 | 324 | avg_minor_gc_cost()->average() >= 0.0) { |
tamao@5120 | 325 | size_t desired_sum = desired_eden_size + desired_promo_size; |
tamao@5120 | 326 | desired_eden_size = adjust_eden_for_footprint(desired_eden_size, desired_sum); |
tamao@5120 | 327 | } |
tamao@5120 | 328 | } |
tamao@5120 | 329 | |
tamao@5120 | 330 | // Note we make the same tests as in the code block below; the code |
tamao@5120 | 331 | // seems a little easier to read with the printing in another block. |
tamao@5120 | 332 | if (PrintAdaptiveSizePolicy) { |
tamao@5120 | 333 | if (desired_eden_size > eden_limit) { |
tamao@5120 | 334 | gclog_or_tty->print_cr( |
tamao@5120 | 335 | "PSAdaptiveSizePolicy::compute_eden_space_size limits:" |
tamao@5120 | 336 | " desired_eden_size: " SIZE_FORMAT |
tamao@5120 | 337 | " old_eden_size: " SIZE_FORMAT |
tamao@5120 | 338 | " eden_limit: " SIZE_FORMAT |
tamao@5120 | 339 | " cur_eden: " SIZE_FORMAT |
tamao@5120 | 340 | " max_eden_size: " SIZE_FORMAT |
tamao@5120 | 341 | " avg_young_live: " SIZE_FORMAT, |
tamao@5120 | 342 | desired_eden_size, _eden_size, eden_limit, cur_eden, |
tamao@5120 | 343 | max_eden_size, (size_t)avg_young_live()->average()); |
tamao@5120 | 344 | } |
tamao@5120 | 345 | if (gc_cost() > gc_cost_limit) { |
tamao@5120 | 346 | gclog_or_tty->print_cr( |
tamao@5120 | 347 | "PSAdaptiveSizePolicy::compute_eden_space_size: gc time limit" |
tamao@5120 | 348 | " gc_cost: %f " |
tamao@5120 | 349 | " GCTimeLimit: %d", |
tamao@5120 | 350 | gc_cost(), GCTimeLimit); |
tamao@5120 | 351 | } |
tamao@5120 | 352 | } |
tamao@5120 | 353 | |
tamao@5120 | 354 | // Align everything and make a final limit check |
jwilhelm@6085 | 355 | desired_eden_size = align_size_up(desired_eden_size, _space_alignment); |
jwilhelm@6085 | 356 | desired_eden_size = MAX2(desired_eden_size, _space_alignment); |
tamao@5120 | 357 | |
jwilhelm@6085 | 358 | eden_limit = align_size_down(eden_limit, _space_alignment); |
tamao@5120 | 359 | |
tamao@5120 | 360 | // And one last limit check, now that we've aligned things. |
tamao@5120 | 361 | if (desired_eden_size > eden_limit) { |
tamao@5120 | 362 | // If the policy says to get a larger eden but |
tamao@5120 | 363 | // is hitting the limit, don't decrease eden. |
tamao@5120 | 364 | // This can lead to a general drifting down of the |
tamao@5120 | 365 | // eden size. Let the tenuring calculation push more |
tamao@5120 | 366 | // into the old gen. |
tamao@5120 | 367 | desired_eden_size = MAX2(eden_limit, cur_eden); |
tamao@5120 | 368 | } |
tamao@5120 | 369 | |
tamao@5120 | 370 | if (PrintAdaptiveSizePolicy) { |
tamao@5120 | 371 | // Timing stats |
tamao@5120 | 372 | gclog_or_tty->print( |
tamao@5120 | 373 | "PSAdaptiveSizePolicy::compute_eden_space_size: costs" |
tamao@5120 | 374 | " minor_time: %f" |
tamao@5120 | 375 | " major_cost: %f" |
tamao@5120 | 376 | " mutator_cost: %f" |
tamao@5120 | 377 | " throughput_goal: %f", |
tamao@5120 | 378 | minor_gc_cost(), major_gc_cost(), mutator_cost(), |
tamao@5120 | 379 | _throughput_goal); |
tamao@5120 | 380 | |
tamao@5120 | 381 | // We give more details if Verbose is set |
tamao@5120 | 382 | if (Verbose) { |
tamao@5120 | 383 | gclog_or_tty->print( " minor_pause: %f" |
tamao@5120 | 384 | " major_pause: %f" |
tamao@5120 | 385 | " minor_interval: %f" |
tamao@5120 | 386 | " major_interval: %f" |
tamao@5120 | 387 | " pause_goal: %f", |
tamao@5120 | 388 | _avg_minor_pause->padded_average(), |
tamao@5120 | 389 | _avg_major_pause->padded_average(), |
tamao@5120 | 390 | _avg_minor_interval->average(), |
tamao@5120 | 391 | _avg_major_interval->average(), |
tamao@5120 | 392 | gc_pause_goal_sec()); |
tamao@5120 | 393 | } |
tamao@5120 | 394 | |
tamao@5120 | 395 | // Footprint stats |
tamao@5120 | 396 | gclog_or_tty->print( " live_space: " SIZE_FORMAT |
tamao@5120 | 397 | " free_space: " SIZE_FORMAT, |
tamao@5120 | 398 | live_space(), free_space()); |
tamao@5120 | 399 | // More detail |
tamao@5120 | 400 | if (Verbose) { |
tamao@5120 | 401 | gclog_or_tty->print( " base_footprint: " SIZE_FORMAT |
tamao@5120 | 402 | " avg_young_live: " SIZE_FORMAT |
tamao@5120 | 403 | " avg_old_live: " SIZE_FORMAT, |
tamao@5120 | 404 | (size_t)_avg_base_footprint->average(), |
tamao@5120 | 405 | (size_t)avg_young_live()->average(), |
tamao@5120 | 406 | (size_t)avg_old_live()->average()); |
tamao@5120 | 407 | } |
tamao@5120 | 408 | |
tamao@5120 | 409 | // And finally, our old and new sizes. |
tamao@5120 | 410 | gclog_or_tty->print(" old_eden_size: " SIZE_FORMAT |
tamao@5120 | 411 | " desired_eden_size: " SIZE_FORMAT, |
tamao@5120 | 412 | _eden_size, desired_eden_size); |
tamao@5120 | 413 | gclog_or_tty->cr(); |
tamao@5120 | 414 | } |
tamao@5120 | 415 | |
tamao@5120 | 416 | set_eden_size(desired_eden_size); |
tamao@5120 | 417 | } |
tamao@5120 | 418 | |
tamao@5120 | 419 | void PSAdaptiveSizePolicy::compute_old_gen_free_space( |
tamao@5120 | 420 | size_t old_live, |
tamao@5120 | 421 | size_t cur_eden, |
tamao@5120 | 422 | size_t max_old_gen_size, |
tamao@5120 | 423 | bool is_full_gc) { |
tamao@5120 | 424 | |
tamao@5120 | 425 | // Update statistics |
tamao@5120 | 426 | // Time statistics are updated as we go, update footprint stats here |
duke@435 | 427 | if (is_full_gc) { |
duke@435 | 428 | // old_live is only accurate after a full gc |
duke@435 | 429 | avg_old_live()->sample(old_live); |
duke@435 | 430 | } |
duke@435 | 431 | |
duke@435 | 432 | // This code used to return if the policy was not ready , i.e., |
duke@435 | 433 | // policy_is_ready() returning false. The intent was that |
duke@435 | 434 | // decisions below needed major collection times and so could |
duke@435 | 435 | // not be made before two major collections. A consequence was |
duke@435 | 436 | // adjustments to the young generation were not done until after |
duke@435 | 437 | // two major collections even if the minor collections times |
duke@435 | 438 | // exceeded the requested goals. Now let the young generation |
duke@435 | 439 | // adjust for the minor collection times. Major collection times |
duke@435 | 440 | // will be zero for the first collection and will naturally be |
duke@435 | 441 | // ignored. Tenured generation adjustments are only made at the |
duke@435 | 442 | // full collections so until the second major collection has |
duke@435 | 443 | // been reached, no tenured generation adjustments will be made. |
duke@435 | 444 | |
duke@435 | 445 | // Until we know better, desired promotion size uses the last calculation |
duke@435 | 446 | size_t desired_promo_size = _promo_size; |
duke@435 | 447 | |
duke@435 | 448 | // Start eden at the current value. The desired value that is stored |
duke@435 | 449 | // in _eden_size is not bounded by constraints of the heap and can |
duke@435 | 450 | // run away. |
duke@435 | 451 | // |
duke@435 | 452 | // As expected setting desired_eden_size to the current |
duke@435 | 453 | // value of desired_eden_size as a starting point |
duke@435 | 454 | // caused desired_eden_size to grow way too large and caused |
duke@435 | 455 | // an overflow down stream. It may have improved performance in |
duke@435 | 456 | // some case but is dangerous. |
duke@435 | 457 | size_t desired_eden_size = cur_eden; |
duke@435 | 458 | |
duke@435 | 459 | // Cache some values. There's a bit of work getting these, so |
duke@435 | 460 | // we might save a little time. |
duke@435 | 461 | const double major_cost = major_gc_cost(); |
duke@435 | 462 | const double minor_cost = minor_gc_cost(); |
duke@435 | 463 | |
duke@435 | 464 | // Limits on our growth |
duke@435 | 465 | size_t promo_limit = (size_t)(max_old_gen_size - avg_old_live()->average()); |
duke@435 | 466 | |
duke@435 | 467 | // But don't force a promo size below the current promo size. Otherwise, |
duke@435 | 468 | // the promo size will shrink for no good reason. |
duke@435 | 469 | promo_limit = MAX2(promo_limit, _promo_size); |
duke@435 | 470 | |
duke@435 | 471 | const double gc_cost_limit = GCTimeLimit/100.0; |
duke@435 | 472 | |
duke@435 | 473 | // Which way should we go? |
duke@435 | 474 | // if pause requirement is not met |
duke@435 | 475 | // adjust size of any generation with average paus exceeding |
duke@435 | 476 | // the pause limit. Adjust one pause at a time (the larger) |
duke@435 | 477 | // and only make adjustments for the major pause at full collections. |
duke@435 | 478 | // else if throughput requirement not met |
duke@435 | 479 | // adjust the size of the generation with larger gc time. Only |
duke@435 | 480 | // adjust one generation at a time. |
duke@435 | 481 | // else |
duke@435 | 482 | // adjust down the total heap size. Adjust down the larger of the |
duke@435 | 483 | // generations. |
duke@435 | 484 | |
duke@435 | 485 | // Add some checks for a threshhold for a change. For example, |
duke@435 | 486 | // a change less than the necessary alignment is probably not worth |
duke@435 | 487 | // attempting. |
duke@435 | 488 | |
duke@435 | 489 | if ((_avg_minor_pause->padded_average() > gc_pause_goal_sec()) || |
duke@435 | 490 | (_avg_major_pause->padded_average() > gc_pause_goal_sec())) { |
duke@435 | 491 | // |
duke@435 | 492 | // Check pauses |
duke@435 | 493 | // |
duke@435 | 494 | // Make changes only to affect one of the pauses (the larger) |
duke@435 | 495 | // at a time. |
tamao@5120 | 496 | if (is_full_gc) { |
tamao@5120 | 497 | set_decide_at_full_gc(decide_at_full_gc_true); |
tamao@5120 | 498 | adjust_promo_for_pause_time(is_full_gc, &desired_promo_size, &desired_eden_size); |
tamao@5120 | 499 | } |
duke@435 | 500 | } else if (_avg_minor_pause->padded_average() > gc_minor_pause_goal_sec()) { |
duke@435 | 501 | // Adjust only for the minor pause time goal |
tamao@5120 | 502 | adjust_promo_for_minor_pause_time(is_full_gc, &desired_promo_size, &desired_eden_size); |
duke@435 | 503 | } else if(adjusted_mutator_cost() < _throughput_goal) { |
duke@435 | 504 | // This branch used to require that (mutator_cost() > 0.0 in 1.4.2. |
duke@435 | 505 | // This sometimes resulted in skipping to the minimize footprint |
duke@435 | 506 | // code. Change this to try and reduce GC time if mutator time is |
duke@435 | 507 | // negative for whatever reason. Or for future consideration, |
duke@435 | 508 | // bail out of the code if mutator time is negative. |
duke@435 | 509 | // |
duke@435 | 510 | // Throughput |
duke@435 | 511 | // |
duke@435 | 512 | assert(major_cost >= 0.0, "major cost is < 0.0"); |
duke@435 | 513 | assert(minor_cost >= 0.0, "minor cost is < 0.0"); |
duke@435 | 514 | // Try to reduce the GC times. |
tamao@5120 | 515 | if (is_full_gc) { |
tamao@5120 | 516 | set_decide_at_full_gc(decide_at_full_gc_true); |
tamao@5120 | 517 | adjust_promo_for_throughput(is_full_gc, &desired_promo_size); |
tamao@5120 | 518 | } |
duke@435 | 519 | } else { |
duke@435 | 520 | |
duke@435 | 521 | // Be conservative about reducing the footprint. |
duke@435 | 522 | // Do a minimum number of major collections first. |
duke@435 | 523 | // Have reasonable averages for major and minor collections costs. |
duke@435 | 524 | if (UseAdaptiveSizePolicyFootprintGoal && |
duke@435 | 525 | young_gen_policy_is_ready() && |
duke@435 | 526 | avg_major_gc_cost()->average() >= 0.0 && |
duke@435 | 527 | avg_minor_gc_cost()->average() >= 0.0) { |
duke@435 | 528 | if (is_full_gc) { |
duke@435 | 529 | set_decide_at_full_gc(decide_at_full_gc_true); |
tamao@5120 | 530 | size_t desired_sum = desired_eden_size + desired_promo_size; |
tamao@5120 | 531 | desired_promo_size = adjust_promo_for_footprint(desired_promo_size, desired_sum); |
duke@435 | 532 | } |
duke@435 | 533 | } |
duke@435 | 534 | } |
duke@435 | 535 | |
duke@435 | 536 | // Note we make the same tests as in the code block below; the code |
duke@435 | 537 | // seems a little easier to read with the printing in another block. |
duke@435 | 538 | if (PrintAdaptiveSizePolicy) { |
duke@435 | 539 | if (desired_promo_size > promo_limit) { |
duke@435 | 540 | // "free_in_old_gen" was the original value for used for promo_limit |
duke@435 | 541 | size_t free_in_old_gen = (size_t)(max_old_gen_size - avg_old_live()->average()); |
duke@435 | 542 | gclog_or_tty->print_cr( |
tamao@5120 | 543 | "PSAdaptiveSizePolicy::compute_old_gen_free_space limits:" |
duke@435 | 544 | " desired_promo_size: " SIZE_FORMAT |
duke@435 | 545 | " promo_limit: " SIZE_FORMAT |
duke@435 | 546 | " free_in_old_gen: " SIZE_FORMAT |
duke@435 | 547 | " max_old_gen_size: " SIZE_FORMAT |
duke@435 | 548 | " avg_old_live: " SIZE_FORMAT, |
duke@435 | 549 | desired_promo_size, promo_limit, free_in_old_gen, |
duke@435 | 550 | max_old_gen_size, (size_t) avg_old_live()->average()); |
duke@435 | 551 | } |
duke@435 | 552 | if (gc_cost() > gc_cost_limit) { |
duke@435 | 553 | gclog_or_tty->print_cr( |
tamao@5120 | 554 | "PSAdaptiveSizePolicy::compute_old_gen_free_space: gc time limit" |
duke@435 | 555 | " gc_cost: %f " |
duke@435 | 556 | " GCTimeLimit: %d", |
duke@435 | 557 | gc_cost(), GCTimeLimit); |
duke@435 | 558 | } |
duke@435 | 559 | } |
duke@435 | 560 | |
duke@435 | 561 | // Align everything and make a final limit check |
jwilhelm@6085 | 562 | desired_promo_size = align_size_up(desired_promo_size, _space_alignment); |
jwilhelm@6085 | 563 | desired_promo_size = MAX2(desired_promo_size, _space_alignment); |
duke@435 | 564 | |
jwilhelm@6085 | 565 | promo_limit = align_size_down(promo_limit, _space_alignment); |
duke@435 | 566 | |
duke@435 | 567 | // And one last limit check, now that we've aligned things. |
duke@435 | 568 | desired_promo_size = MIN2(desired_promo_size, promo_limit); |
duke@435 | 569 | |
duke@435 | 570 | if (PrintAdaptiveSizePolicy) { |
duke@435 | 571 | // Timing stats |
duke@435 | 572 | gclog_or_tty->print( |
tamao@5120 | 573 | "PSAdaptiveSizePolicy::compute_old_gen_free_space: costs" |
duke@435 | 574 | " minor_time: %f" |
duke@435 | 575 | " major_cost: %f" |
duke@435 | 576 | " mutator_cost: %f" |
duke@435 | 577 | " throughput_goal: %f", |
duke@435 | 578 | minor_gc_cost(), major_gc_cost(), mutator_cost(), |
duke@435 | 579 | _throughput_goal); |
duke@435 | 580 | |
duke@435 | 581 | // We give more details if Verbose is set |
duke@435 | 582 | if (Verbose) { |
duke@435 | 583 | gclog_or_tty->print( " minor_pause: %f" |
duke@435 | 584 | " major_pause: %f" |
duke@435 | 585 | " minor_interval: %f" |
duke@435 | 586 | " major_interval: %f" |
duke@435 | 587 | " pause_goal: %f", |
duke@435 | 588 | _avg_minor_pause->padded_average(), |
duke@435 | 589 | _avg_major_pause->padded_average(), |
duke@435 | 590 | _avg_minor_interval->average(), |
duke@435 | 591 | _avg_major_interval->average(), |
duke@435 | 592 | gc_pause_goal_sec()); |
duke@435 | 593 | } |
duke@435 | 594 | |
duke@435 | 595 | // Footprint stats |
duke@435 | 596 | gclog_or_tty->print( " live_space: " SIZE_FORMAT |
duke@435 | 597 | " free_space: " SIZE_FORMAT, |
duke@435 | 598 | live_space(), free_space()); |
duke@435 | 599 | // More detail |
duke@435 | 600 | if (Verbose) { |
duke@435 | 601 | gclog_or_tty->print( " base_footprint: " SIZE_FORMAT |
duke@435 | 602 | " avg_young_live: " SIZE_FORMAT |
duke@435 | 603 | " avg_old_live: " SIZE_FORMAT, |
duke@435 | 604 | (size_t)_avg_base_footprint->average(), |
duke@435 | 605 | (size_t)avg_young_live()->average(), |
duke@435 | 606 | (size_t)avg_old_live()->average()); |
duke@435 | 607 | } |
duke@435 | 608 | |
duke@435 | 609 | // And finally, our old and new sizes. |
duke@435 | 610 | gclog_or_tty->print(" old_promo_size: " SIZE_FORMAT |
tamao@5120 | 611 | " desired_promo_size: " SIZE_FORMAT, |
tamao@5120 | 612 | _promo_size, desired_promo_size); |
duke@435 | 613 | gclog_or_tty->cr(); |
duke@435 | 614 | } |
duke@435 | 615 | |
duke@435 | 616 | set_promo_size(desired_promo_size); |
tamao@5120 | 617 | } |
duke@435 | 618 | |
duke@435 | 619 | void PSAdaptiveSizePolicy::decay_supplemental_growth(bool is_full_gc) { |
duke@435 | 620 | // Decay the supplemental increment? Decay the supplement growth |
duke@435 | 621 | // factor even if it is not used. It is only meant to give a boost |
duke@435 | 622 | // to the initial growth and if it is not used, then it was not |
duke@435 | 623 | // needed. |
duke@435 | 624 | if (is_full_gc) { |
duke@435 | 625 | // Don't wait for the threshold value for the major collections. If |
duke@435 | 626 | // here, the supplemental growth term was used and should decay. |
duke@435 | 627 | if ((_avg_major_pause->count() % TenuredGenerationSizeSupplementDecay) |
duke@435 | 628 | == 0) { |
duke@435 | 629 | _old_gen_size_increment_supplement = |
duke@435 | 630 | _old_gen_size_increment_supplement >> 1; |
duke@435 | 631 | } |
duke@435 | 632 | } else { |
duke@435 | 633 | if ((_avg_minor_pause->count() >= AdaptiveSizePolicyReadyThreshold) && |
duke@435 | 634 | (_avg_minor_pause->count() % YoungGenerationSizeSupplementDecay) == 0) { |
duke@435 | 635 | _young_gen_size_increment_supplement = |
duke@435 | 636 | _young_gen_size_increment_supplement >> 1; |
duke@435 | 637 | } |
duke@435 | 638 | } |
duke@435 | 639 | } |
duke@435 | 640 | |
tamao@5120 | 641 | void PSAdaptiveSizePolicy::adjust_promo_for_minor_pause_time(bool is_full_gc, |
duke@435 | 642 | size_t* desired_promo_size_ptr, size_t* desired_eden_size_ptr) { |
duke@435 | 643 | |
tamao@5120 | 644 | if (PSAdjustTenuredGenForMinorPause) { |
tamao@5120 | 645 | if (is_full_gc) { |
tamao@5120 | 646 | set_decide_at_full_gc(decide_at_full_gc_true); |
tamao@5120 | 647 | } |
tamao@5120 | 648 | // If the desired eden size is as small as it will get, |
tamao@5120 | 649 | // try to adjust the old gen size. |
jwilhelm@6085 | 650 | if (*desired_eden_size_ptr <= _space_alignment) { |
tamao@5120 | 651 | // Vary the old gen size to reduce the young gen pause. This |
tamao@5120 | 652 | // may not be a good idea. This is just a test. |
tamao@5120 | 653 | if (minor_pause_old_estimator()->decrement_will_decrease()) { |
tamao@5120 | 654 | set_change_old_gen_for_min_pauses(decrease_old_gen_for_min_pauses_true); |
tamao@5120 | 655 | *desired_promo_size_ptr = |
tamao@5120 | 656 | _promo_size - promo_decrement_aligned_down(*desired_promo_size_ptr); |
tamao@5120 | 657 | } else { |
tamao@5120 | 658 | set_change_old_gen_for_min_pauses(increase_old_gen_for_min_pauses_true); |
tamao@5120 | 659 | size_t promo_heap_delta = |
tamao@5120 | 660 | promo_increment_with_supplement_aligned_up(*desired_promo_size_ptr); |
tamao@5120 | 661 | if ((*desired_promo_size_ptr + promo_heap_delta) > |
tamao@5120 | 662 | *desired_promo_size_ptr) { |
tamao@5120 | 663 | *desired_promo_size_ptr = |
tamao@5120 | 664 | _promo_size + promo_heap_delta; |
tamao@5120 | 665 | } |
tamao@5120 | 666 | } |
tamao@5120 | 667 | } |
tamao@5120 | 668 | } |
tamao@5120 | 669 | } |
tamao@5120 | 670 | |
tamao@5120 | 671 | void PSAdaptiveSizePolicy::adjust_eden_for_minor_pause_time(bool is_full_gc, |
tamao@5120 | 672 | size_t* desired_eden_size_ptr) { |
tamao@5120 | 673 | |
duke@435 | 674 | // Adjust the young generation size to reduce pause time of |
duke@435 | 675 | // of collections. |
duke@435 | 676 | // |
duke@435 | 677 | // The AdaptiveSizePolicyInitializingSteps test is not used |
duke@435 | 678 | // here. It has not seemed to be needed but perhaps should |
duke@435 | 679 | // be added for consistency. |
duke@435 | 680 | if (minor_pause_young_estimator()->decrement_will_decrease()) { |
duke@435 | 681 | // reduce eden size |
duke@435 | 682 | set_change_young_gen_for_min_pauses( |
duke@435 | 683 | decrease_young_gen_for_min_pauses_true); |
duke@435 | 684 | *desired_eden_size_ptr = *desired_eden_size_ptr - |
duke@435 | 685 | eden_decrement_aligned_down(*desired_eden_size_ptr); |
duke@435 | 686 | } else { |
duke@435 | 687 | // EXPERIMENTAL ADJUSTMENT |
duke@435 | 688 | // Only record that the estimator indicated such an action. |
duke@435 | 689 | // *desired_eden_size_ptr = *desired_eden_size_ptr + eden_heap_delta; |
duke@435 | 690 | set_change_young_gen_for_min_pauses( |
duke@435 | 691 | increase_young_gen_for_min_pauses_true); |
duke@435 | 692 | } |
duke@435 | 693 | } |
duke@435 | 694 | |
tamao@5120 | 695 | void PSAdaptiveSizePolicy::adjust_promo_for_pause_time(bool is_full_gc, |
duke@435 | 696 | size_t* desired_promo_size_ptr, |
duke@435 | 697 | size_t* desired_eden_size_ptr) { |
duke@435 | 698 | |
duke@435 | 699 | size_t promo_heap_delta = 0; |
tamao@5120 | 700 | // Add some checks for a threshold for a change. For example, |
duke@435 | 701 | // a change less than the required alignment is probably not worth |
duke@435 | 702 | // attempting. |
duke@435 | 703 | |
duke@435 | 704 | if (_avg_minor_pause->padded_average() > _avg_major_pause->padded_average()) { |
tamao@5120 | 705 | adjust_promo_for_minor_pause_time(is_full_gc, desired_promo_size_ptr, desired_eden_size_ptr); |
duke@435 | 706 | // major pause adjustments |
duke@435 | 707 | } else if (is_full_gc) { |
duke@435 | 708 | // Adjust for the major pause time only at full gc's because the |
duke@435 | 709 | // affects of a change can only be seen at full gc's. |
duke@435 | 710 | |
duke@435 | 711 | // Reduce old generation size to reduce pause? |
duke@435 | 712 | if (major_pause_old_estimator()->decrement_will_decrease()) { |
duke@435 | 713 | // reduce old generation size |
duke@435 | 714 | set_change_old_gen_for_maj_pauses(decrease_old_gen_for_maj_pauses_true); |
duke@435 | 715 | promo_heap_delta = promo_decrement_aligned_down(*desired_promo_size_ptr); |
duke@435 | 716 | *desired_promo_size_ptr = _promo_size - promo_heap_delta; |
duke@435 | 717 | } else { |
duke@435 | 718 | // EXPERIMENTAL ADJUSTMENT |
duke@435 | 719 | // Only record that the estimator indicated such an action. |
duke@435 | 720 | // *desired_promo_size_ptr = _promo_size + |
duke@435 | 721 | // promo_increment_aligned_up(*desired_promo_size_ptr); |
duke@435 | 722 | set_change_old_gen_for_maj_pauses(increase_old_gen_for_maj_pauses_true); |
duke@435 | 723 | } |
tamao@5120 | 724 | } |
tamao@5120 | 725 | |
tamao@5120 | 726 | if (PrintAdaptiveSizePolicy && Verbose) { |
tamao@5120 | 727 | gclog_or_tty->print_cr( |
tamao@5192 | 728 | "PSAdaptiveSizePolicy::adjust_promo_for_pause_time " |
tamao@5120 | 729 | "adjusting gen sizes for major pause (avg %f goal %f). " |
tamao@5120 | 730 | "desired_promo_size " SIZE_FORMAT " promo delta " SIZE_FORMAT, |
tamao@5120 | 731 | _avg_major_pause->average(), gc_pause_goal_sec(), |
tamao@5120 | 732 | *desired_promo_size_ptr, promo_heap_delta); |
tamao@5120 | 733 | } |
tamao@5120 | 734 | } |
tamao@5120 | 735 | |
tamao@5120 | 736 | void PSAdaptiveSizePolicy::adjust_eden_for_pause_time(bool is_full_gc, |
tamao@5120 | 737 | size_t* desired_promo_size_ptr, |
tamao@5120 | 738 | size_t* desired_eden_size_ptr) { |
tamao@5120 | 739 | |
tamao@5120 | 740 | size_t eden_heap_delta = 0; |
tamao@5120 | 741 | // Add some checks for a threshold for a change. For example, |
tamao@5120 | 742 | // a change less than the required alignment is probably not worth |
tamao@5120 | 743 | // attempting. |
tamao@5120 | 744 | if (_avg_minor_pause->padded_average() > _avg_major_pause->padded_average()) { |
tamao@5120 | 745 | adjust_eden_for_minor_pause_time(is_full_gc, |
tamao@5120 | 746 | desired_eden_size_ptr); |
tamao@5120 | 747 | // major pause adjustments |
tamao@5120 | 748 | } else if (is_full_gc) { |
tamao@5120 | 749 | // Adjust for the major pause time only at full gc's because the |
tamao@5120 | 750 | // affects of a change can only be seen at full gc's. |
duke@435 | 751 | if (PSAdjustYoungGenForMajorPause) { |
duke@435 | 752 | // If the promo size is at the minimum (i.e., the old gen |
duke@435 | 753 | // size will not actually decrease), consider changing the |
duke@435 | 754 | // young gen size. |
jwilhelm@6085 | 755 | if (*desired_promo_size_ptr < _space_alignment) { |
duke@435 | 756 | // If increasing the young generation will decrease the old gen |
duke@435 | 757 | // pause, do it. |
duke@435 | 758 | // During startup there is noise in the statistics for deciding |
duke@435 | 759 | // on whether to increase or decrease the young gen size. For |
duke@435 | 760 | // some number of iterations, just try to increase the young |
duke@435 | 761 | // gen size if the major pause is too long to try and establish |
duke@435 | 762 | // good statistics for later decisions. |
duke@435 | 763 | if (major_pause_young_estimator()->increment_will_decrease() || |
duke@435 | 764 | (_young_gen_change_for_major_pause_count |
duke@435 | 765 | <= AdaptiveSizePolicyInitializingSteps)) { |
duke@435 | 766 | set_change_young_gen_for_maj_pauses( |
duke@435 | 767 | increase_young_gen_for_maj_pauses_true); |
duke@435 | 768 | eden_heap_delta = eden_increment_aligned_up(*desired_eden_size_ptr); |
duke@435 | 769 | *desired_eden_size_ptr = _eden_size + eden_heap_delta; |
duke@435 | 770 | _young_gen_change_for_major_pause_count++; |
duke@435 | 771 | } else { |
duke@435 | 772 | // Record that decreasing the young gen size would decrease |
duke@435 | 773 | // the major pause |
duke@435 | 774 | set_change_young_gen_for_maj_pauses( |
duke@435 | 775 | decrease_young_gen_for_maj_pauses_true); |
duke@435 | 776 | eden_heap_delta = eden_decrement_aligned_down(*desired_eden_size_ptr); |
duke@435 | 777 | *desired_eden_size_ptr = _eden_size - eden_heap_delta; |
duke@435 | 778 | } |
duke@435 | 779 | } |
duke@435 | 780 | } |
duke@435 | 781 | } |
duke@435 | 782 | |
duke@435 | 783 | if (PrintAdaptiveSizePolicy && Verbose) { |
duke@435 | 784 | gclog_or_tty->print_cr( |
tamao@5192 | 785 | "PSAdaptiveSizePolicy::adjust_eden_for_pause_time " |
duke@435 | 786 | "adjusting gen sizes for major pause (avg %f goal %f). " |
tamao@5120 | 787 | "desired_eden_size " SIZE_FORMAT " eden delta " SIZE_FORMAT, |
duke@435 | 788 | _avg_major_pause->average(), gc_pause_goal_sec(), |
tamao@5120 | 789 | *desired_eden_size_ptr, eden_heap_delta); |
duke@435 | 790 | } |
duke@435 | 791 | } |
duke@435 | 792 | |
tamao@5120 | 793 | void PSAdaptiveSizePolicy::adjust_promo_for_throughput(bool is_full_gc, |
tamao@5120 | 794 | size_t* desired_promo_size_ptr) { |
duke@435 | 795 | |
tamao@5120 | 796 | // Add some checks for a threshold for a change. For example, |
duke@435 | 797 | // a change less than the required alignment is probably not worth |
duke@435 | 798 | // attempting. |
duke@435 | 799 | |
duke@435 | 800 | if ((gc_cost() + mutator_cost()) == 0.0) { |
duke@435 | 801 | return; |
duke@435 | 802 | } |
duke@435 | 803 | |
duke@435 | 804 | if (PrintAdaptiveSizePolicy && Verbose) { |
tamao@5120 | 805 | gclog_or_tty->print("\nPSAdaptiveSizePolicy::adjust_promo_for_throughput(" |
tamao@5120 | 806 | "is_full: %d, promo: " SIZE_FORMAT "): ", |
tamao@5120 | 807 | is_full_gc, *desired_promo_size_ptr); |
duke@435 | 808 | gclog_or_tty->print_cr("mutator_cost %f major_gc_cost %f " |
duke@435 | 809 | "minor_gc_cost %f", mutator_cost(), major_gc_cost(), minor_gc_cost()); |
duke@435 | 810 | } |
duke@435 | 811 | |
duke@435 | 812 | // Tenured generation |
duke@435 | 813 | if (is_full_gc) { |
duke@435 | 814 | // Calculate the change to use for the tenured gen. |
duke@435 | 815 | size_t scaled_promo_heap_delta = 0; |
duke@435 | 816 | // Can the increment to the generation be scaled? |
duke@435 | 817 | if (gc_cost() >= 0.0 && major_gc_cost() >= 0.0) { |
duke@435 | 818 | size_t promo_heap_delta = |
duke@435 | 819 | promo_increment_with_supplement_aligned_up(*desired_promo_size_ptr); |
duke@435 | 820 | double scale_by_ratio = major_gc_cost() / gc_cost(); |
duke@435 | 821 | scaled_promo_heap_delta = |
duke@435 | 822 | (size_t) (scale_by_ratio * (double) promo_heap_delta); |
duke@435 | 823 | if (PrintAdaptiveSizePolicy && Verbose) { |
duke@435 | 824 | gclog_or_tty->print_cr( |
duke@435 | 825 | "Scaled tenured increment: " SIZE_FORMAT " by %f down to " |
duke@435 | 826 | SIZE_FORMAT, |
duke@435 | 827 | promo_heap_delta, scale_by_ratio, scaled_promo_heap_delta); |
duke@435 | 828 | } |
duke@435 | 829 | } else if (major_gc_cost() >= 0.0) { |
duke@435 | 830 | // Scaling is not going to work. If the major gc time is the |
duke@435 | 831 | // larger, give it a full increment. |
duke@435 | 832 | if (major_gc_cost() >= minor_gc_cost()) { |
duke@435 | 833 | scaled_promo_heap_delta = |
duke@435 | 834 | promo_increment_with_supplement_aligned_up(*desired_promo_size_ptr); |
duke@435 | 835 | } |
duke@435 | 836 | } else { |
duke@435 | 837 | // Don't expect to get here but it's ok if it does |
duke@435 | 838 | // in the product build since the delta will be 0 |
duke@435 | 839 | // and nothing will change. |
duke@435 | 840 | assert(false, "Unexpected value for gc costs"); |
duke@435 | 841 | } |
duke@435 | 842 | |
duke@435 | 843 | switch (AdaptiveSizeThroughPutPolicy) { |
duke@435 | 844 | case 1: |
duke@435 | 845 | // Early in the run the statistics might not be good. Until |
duke@435 | 846 | // a specific number of collections have been, use the heuristic |
duke@435 | 847 | // that a larger generation size means lower collection costs. |
duke@435 | 848 | if (major_collection_estimator()->increment_will_decrease() || |
duke@435 | 849 | (_old_gen_change_for_major_throughput |
duke@435 | 850 | <= AdaptiveSizePolicyInitializingSteps)) { |
duke@435 | 851 | // Increase tenured generation size to reduce major collection cost |
duke@435 | 852 | if ((*desired_promo_size_ptr + scaled_promo_heap_delta) > |
duke@435 | 853 | *desired_promo_size_ptr) { |
duke@435 | 854 | *desired_promo_size_ptr = _promo_size + scaled_promo_heap_delta; |
duke@435 | 855 | } |
duke@435 | 856 | set_change_old_gen_for_throughput( |
duke@435 | 857 | increase_old_gen_for_throughput_true); |
duke@435 | 858 | _old_gen_change_for_major_throughput++; |
duke@435 | 859 | } else { |
duke@435 | 860 | // EXPERIMENTAL ADJUSTMENT |
duke@435 | 861 | // Record that decreasing the old gen size would decrease |
duke@435 | 862 | // the major collection cost but don't do it. |
duke@435 | 863 | // *desired_promo_size_ptr = _promo_size - |
duke@435 | 864 | // promo_decrement_aligned_down(*desired_promo_size_ptr); |
duke@435 | 865 | set_change_old_gen_for_throughput( |
duke@435 | 866 | decrease_old_gen_for_throughput_true); |
duke@435 | 867 | } |
duke@435 | 868 | |
duke@435 | 869 | break; |
duke@435 | 870 | default: |
duke@435 | 871 | // Simplest strategy |
duke@435 | 872 | if ((*desired_promo_size_ptr + scaled_promo_heap_delta) > |
duke@435 | 873 | *desired_promo_size_ptr) { |
duke@435 | 874 | *desired_promo_size_ptr = *desired_promo_size_ptr + |
duke@435 | 875 | scaled_promo_heap_delta; |
duke@435 | 876 | } |
duke@435 | 877 | set_change_old_gen_for_throughput( |
duke@435 | 878 | increase_old_gen_for_throughput_true); |
duke@435 | 879 | _old_gen_change_for_major_throughput++; |
duke@435 | 880 | } |
duke@435 | 881 | |
duke@435 | 882 | if (PrintAdaptiveSizePolicy && Verbose) { |
duke@435 | 883 | gclog_or_tty->print_cr( |
duke@435 | 884 | "adjusting tenured gen for throughput (avg %f goal %f). " |
duke@435 | 885 | "desired_promo_size " SIZE_FORMAT " promo_delta " SIZE_FORMAT , |
duke@435 | 886 | mutator_cost(), _throughput_goal, |
duke@435 | 887 | *desired_promo_size_ptr, scaled_promo_heap_delta); |
duke@435 | 888 | } |
duke@435 | 889 | } |
tamao@5120 | 890 | } |
tamao@5120 | 891 | |
tamao@5120 | 892 | void PSAdaptiveSizePolicy::adjust_eden_for_throughput(bool is_full_gc, |
tamao@5120 | 893 | size_t* desired_eden_size_ptr) { |
tamao@5120 | 894 | |
tamao@5120 | 895 | // Add some checks for a threshold for a change. For example, |
tamao@5120 | 896 | // a change less than the required alignment is probably not worth |
tamao@5120 | 897 | // attempting. |
tamao@5120 | 898 | |
tamao@5120 | 899 | if ((gc_cost() + mutator_cost()) == 0.0) { |
tamao@5120 | 900 | return; |
tamao@5120 | 901 | } |
tamao@5120 | 902 | |
tamao@5120 | 903 | if (PrintAdaptiveSizePolicy && Verbose) { |
tamao@5120 | 904 | gclog_or_tty->print("\nPSAdaptiveSizePolicy::adjust_eden_for_throughput(" |
tamao@5120 | 905 | "is_full: %d, cur_eden: " SIZE_FORMAT "): ", |
tamao@5120 | 906 | is_full_gc, *desired_eden_size_ptr); |
tamao@5120 | 907 | gclog_or_tty->print_cr("mutator_cost %f major_gc_cost %f " |
tamao@5120 | 908 | "minor_gc_cost %f", mutator_cost(), major_gc_cost(), minor_gc_cost()); |
tamao@5120 | 909 | } |
duke@435 | 910 | |
duke@435 | 911 | // Young generation |
duke@435 | 912 | size_t scaled_eden_heap_delta = 0; |
duke@435 | 913 | // Can the increment to the generation be scaled? |
duke@435 | 914 | if (gc_cost() >= 0.0 && minor_gc_cost() >= 0.0) { |
duke@435 | 915 | size_t eden_heap_delta = |
duke@435 | 916 | eden_increment_with_supplement_aligned_up(*desired_eden_size_ptr); |
duke@435 | 917 | double scale_by_ratio = minor_gc_cost() / gc_cost(); |
duke@435 | 918 | assert(scale_by_ratio <= 1.0 && scale_by_ratio >= 0.0, "Scaling is wrong"); |
duke@435 | 919 | scaled_eden_heap_delta = |
duke@435 | 920 | (size_t) (scale_by_ratio * (double) eden_heap_delta); |
duke@435 | 921 | if (PrintAdaptiveSizePolicy && Verbose) { |
duke@435 | 922 | gclog_or_tty->print_cr( |
duke@435 | 923 | "Scaled eden increment: " SIZE_FORMAT " by %f down to " |
duke@435 | 924 | SIZE_FORMAT, |
duke@435 | 925 | eden_heap_delta, scale_by_ratio, scaled_eden_heap_delta); |
duke@435 | 926 | } |
duke@435 | 927 | } else if (minor_gc_cost() >= 0.0) { |
duke@435 | 928 | // Scaling is not going to work. If the minor gc time is the |
duke@435 | 929 | // larger, give it a full increment. |
duke@435 | 930 | if (minor_gc_cost() > major_gc_cost()) { |
duke@435 | 931 | scaled_eden_heap_delta = |
duke@435 | 932 | eden_increment_with_supplement_aligned_up(*desired_eden_size_ptr); |
duke@435 | 933 | } |
duke@435 | 934 | } else { |
duke@435 | 935 | // Don't expect to get here but it's ok if it does |
duke@435 | 936 | // in the product build since the delta will be 0 |
duke@435 | 937 | // and nothing will change. |
duke@435 | 938 | assert(false, "Unexpected value for gc costs"); |
duke@435 | 939 | } |
duke@435 | 940 | |
duke@435 | 941 | // Use a heuristic for some number of collections to give |
duke@435 | 942 | // the averages time to settle down. |
duke@435 | 943 | switch (AdaptiveSizeThroughPutPolicy) { |
duke@435 | 944 | case 1: |
duke@435 | 945 | if (minor_collection_estimator()->increment_will_decrease() || |
duke@435 | 946 | (_young_gen_change_for_minor_throughput |
duke@435 | 947 | <= AdaptiveSizePolicyInitializingSteps)) { |
duke@435 | 948 | // Expand young generation size to reduce frequency of |
duke@435 | 949 | // of collections. |
duke@435 | 950 | if ((*desired_eden_size_ptr + scaled_eden_heap_delta) > |
duke@435 | 951 | *desired_eden_size_ptr) { |
duke@435 | 952 | *desired_eden_size_ptr = |
duke@435 | 953 | *desired_eden_size_ptr + scaled_eden_heap_delta; |
duke@435 | 954 | } |
duke@435 | 955 | set_change_young_gen_for_throughput( |
duke@435 | 956 | increase_young_gen_for_througput_true); |
duke@435 | 957 | _young_gen_change_for_minor_throughput++; |
duke@435 | 958 | } else { |
duke@435 | 959 | // EXPERIMENTAL ADJUSTMENT |
duke@435 | 960 | // Record that decreasing the young gen size would decrease |
duke@435 | 961 | // the minor collection cost but don't do it. |
duke@435 | 962 | // *desired_eden_size_ptr = _eden_size - |
duke@435 | 963 | // eden_decrement_aligned_down(*desired_eden_size_ptr); |
duke@435 | 964 | set_change_young_gen_for_throughput( |
duke@435 | 965 | decrease_young_gen_for_througput_true); |
duke@435 | 966 | } |
duke@435 | 967 | break; |
duke@435 | 968 | default: |
duke@435 | 969 | if ((*desired_eden_size_ptr + scaled_eden_heap_delta) > |
duke@435 | 970 | *desired_eden_size_ptr) { |
duke@435 | 971 | *desired_eden_size_ptr = |
duke@435 | 972 | *desired_eden_size_ptr + scaled_eden_heap_delta; |
duke@435 | 973 | } |
duke@435 | 974 | set_change_young_gen_for_throughput( |
duke@435 | 975 | increase_young_gen_for_througput_true); |
duke@435 | 976 | _young_gen_change_for_minor_throughput++; |
duke@435 | 977 | } |
duke@435 | 978 | |
duke@435 | 979 | if (PrintAdaptiveSizePolicy && Verbose) { |
duke@435 | 980 | gclog_or_tty->print_cr( |
duke@435 | 981 | "adjusting eden for throughput (avg %f goal %f). desired_eden_size " |
duke@435 | 982 | SIZE_FORMAT " eden delta " SIZE_FORMAT "\n", |
duke@435 | 983 | mutator_cost(), _throughput_goal, |
duke@435 | 984 | *desired_eden_size_ptr, scaled_eden_heap_delta); |
duke@435 | 985 | } |
duke@435 | 986 | } |
duke@435 | 987 | |
duke@435 | 988 | size_t PSAdaptiveSizePolicy::adjust_promo_for_footprint( |
duke@435 | 989 | size_t desired_promo_size, size_t desired_sum) { |
duke@435 | 990 | assert(desired_promo_size <= desired_sum, "Inconsistent parameters"); |
duke@435 | 991 | set_decrease_for_footprint(decrease_old_gen_for_footprint_true); |
duke@435 | 992 | |
duke@435 | 993 | size_t change = promo_decrement(desired_promo_size); |
duke@435 | 994 | change = scale_down(change, desired_promo_size, desired_sum); |
duke@435 | 995 | |
duke@435 | 996 | size_t reduced_size = desired_promo_size - change; |
duke@435 | 997 | |
duke@435 | 998 | if (PrintAdaptiveSizePolicy && Verbose) { |
duke@435 | 999 | gclog_or_tty->print_cr( |
tamao@5192 | 1000 | "AdaptiveSizePolicy::adjust_promo_for_footprint " |
duke@435 | 1001 | "adjusting tenured gen for footprint. " |
duke@435 | 1002 | "starting promo size " SIZE_FORMAT |
duke@435 | 1003 | " reduced promo size " SIZE_FORMAT, |
duke@435 | 1004 | " promo delta " SIZE_FORMAT, |
duke@435 | 1005 | desired_promo_size, reduced_size, change ); |
duke@435 | 1006 | } |
duke@435 | 1007 | |
duke@435 | 1008 | assert(reduced_size <= desired_promo_size, "Inconsistent result"); |
duke@435 | 1009 | return reduced_size; |
duke@435 | 1010 | } |
duke@435 | 1011 | |
duke@435 | 1012 | size_t PSAdaptiveSizePolicy::adjust_eden_for_footprint( |
duke@435 | 1013 | size_t desired_eden_size, size_t desired_sum) { |
duke@435 | 1014 | assert(desired_eden_size <= desired_sum, "Inconsistent parameters"); |
duke@435 | 1015 | set_decrease_for_footprint(decrease_young_gen_for_footprint_true); |
duke@435 | 1016 | |
duke@435 | 1017 | size_t change = eden_decrement(desired_eden_size); |
duke@435 | 1018 | change = scale_down(change, desired_eden_size, desired_sum); |
duke@435 | 1019 | |
duke@435 | 1020 | size_t reduced_size = desired_eden_size - change; |
duke@435 | 1021 | |
duke@435 | 1022 | if (PrintAdaptiveSizePolicy && Verbose) { |
duke@435 | 1023 | gclog_or_tty->print_cr( |
tamao@5192 | 1024 | "AdaptiveSizePolicy::adjust_eden_for_footprint " |
duke@435 | 1025 | "adjusting eden for footprint. " |
duke@435 | 1026 | " starting eden size " SIZE_FORMAT |
duke@435 | 1027 | " reduced eden size " SIZE_FORMAT |
duke@435 | 1028 | " eden delta " SIZE_FORMAT, |
duke@435 | 1029 | desired_eden_size, reduced_size, change); |
duke@435 | 1030 | } |
duke@435 | 1031 | |
duke@435 | 1032 | assert(reduced_size <= desired_eden_size, "Inconsistent result"); |
duke@435 | 1033 | return reduced_size; |
duke@435 | 1034 | } |
duke@435 | 1035 | |
duke@435 | 1036 | // Scale down "change" by the factor |
duke@435 | 1037 | // part / total |
duke@435 | 1038 | // Don't align the results. |
duke@435 | 1039 | |
duke@435 | 1040 | size_t PSAdaptiveSizePolicy::scale_down(size_t change, |
duke@435 | 1041 | double part, |
duke@435 | 1042 | double total) { |
duke@435 | 1043 | assert(part <= total, "Inconsistent input"); |
duke@435 | 1044 | size_t reduced_change = change; |
duke@435 | 1045 | if (total > 0) { |
duke@435 | 1046 | double fraction = part / total; |
duke@435 | 1047 | reduced_change = (size_t) (fraction * (double) change); |
duke@435 | 1048 | } |
duke@435 | 1049 | assert(reduced_change <= change, "Inconsistent result"); |
duke@435 | 1050 | return reduced_change; |
duke@435 | 1051 | } |
duke@435 | 1052 | |
duke@435 | 1053 | size_t PSAdaptiveSizePolicy::eden_increment(size_t cur_eden, |
duke@435 | 1054 | uint percent_change) { |
duke@435 | 1055 | size_t eden_heap_delta; |
duke@435 | 1056 | eden_heap_delta = cur_eden / 100 * percent_change; |
duke@435 | 1057 | return eden_heap_delta; |
duke@435 | 1058 | } |
duke@435 | 1059 | |
duke@435 | 1060 | size_t PSAdaptiveSizePolicy::eden_increment(size_t cur_eden) { |
duke@435 | 1061 | return eden_increment(cur_eden, YoungGenerationSizeIncrement); |
duke@435 | 1062 | } |
duke@435 | 1063 | |
duke@435 | 1064 | size_t PSAdaptiveSizePolicy::eden_increment_aligned_up(size_t cur_eden) { |
duke@435 | 1065 | size_t result = eden_increment(cur_eden, YoungGenerationSizeIncrement); |
jwilhelm@6085 | 1066 | return align_size_up(result, _space_alignment); |
duke@435 | 1067 | } |
duke@435 | 1068 | |
duke@435 | 1069 | size_t PSAdaptiveSizePolicy::eden_increment_aligned_down(size_t cur_eden) { |
duke@435 | 1070 | size_t result = eden_increment(cur_eden); |
jwilhelm@6085 | 1071 | return align_size_down(result, _space_alignment); |
duke@435 | 1072 | } |
duke@435 | 1073 | |
duke@435 | 1074 | size_t PSAdaptiveSizePolicy::eden_increment_with_supplement_aligned_up( |
duke@435 | 1075 | size_t cur_eden) { |
duke@435 | 1076 | size_t result = eden_increment(cur_eden, |
duke@435 | 1077 | YoungGenerationSizeIncrement + _young_gen_size_increment_supplement); |
jwilhelm@6085 | 1078 | return align_size_up(result, _space_alignment); |
duke@435 | 1079 | } |
duke@435 | 1080 | |
duke@435 | 1081 | size_t PSAdaptiveSizePolicy::eden_decrement_aligned_down(size_t cur_eden) { |
duke@435 | 1082 | size_t eden_heap_delta = eden_decrement(cur_eden); |
jwilhelm@6085 | 1083 | return align_size_down(eden_heap_delta, _space_alignment); |
duke@435 | 1084 | } |
duke@435 | 1085 | |
duke@435 | 1086 | size_t PSAdaptiveSizePolicy::eden_decrement(size_t cur_eden) { |
duke@435 | 1087 | size_t eden_heap_delta = eden_increment(cur_eden) / |
duke@435 | 1088 | AdaptiveSizeDecrementScaleFactor; |
duke@435 | 1089 | return eden_heap_delta; |
duke@435 | 1090 | } |
duke@435 | 1091 | |
duke@435 | 1092 | size_t PSAdaptiveSizePolicy::promo_increment(size_t cur_promo, |
duke@435 | 1093 | uint percent_change) { |
duke@435 | 1094 | size_t promo_heap_delta; |
duke@435 | 1095 | promo_heap_delta = cur_promo / 100 * percent_change; |
duke@435 | 1096 | return promo_heap_delta; |
duke@435 | 1097 | } |
duke@435 | 1098 | |
duke@435 | 1099 | size_t PSAdaptiveSizePolicy::promo_increment(size_t cur_promo) { |
duke@435 | 1100 | return promo_increment(cur_promo, TenuredGenerationSizeIncrement); |
duke@435 | 1101 | } |
duke@435 | 1102 | |
duke@435 | 1103 | size_t PSAdaptiveSizePolicy::promo_increment_aligned_up(size_t cur_promo) { |
duke@435 | 1104 | size_t result = promo_increment(cur_promo, TenuredGenerationSizeIncrement); |
jwilhelm@6085 | 1105 | return align_size_up(result, _space_alignment); |
duke@435 | 1106 | } |
duke@435 | 1107 | |
duke@435 | 1108 | size_t PSAdaptiveSizePolicy::promo_increment_aligned_down(size_t cur_promo) { |
duke@435 | 1109 | size_t result = promo_increment(cur_promo, TenuredGenerationSizeIncrement); |
jwilhelm@6085 | 1110 | return align_size_down(result, _space_alignment); |
duke@435 | 1111 | } |
duke@435 | 1112 | |
duke@435 | 1113 | size_t PSAdaptiveSizePolicy::promo_increment_with_supplement_aligned_up( |
duke@435 | 1114 | size_t cur_promo) { |
duke@435 | 1115 | size_t result = promo_increment(cur_promo, |
duke@435 | 1116 | TenuredGenerationSizeIncrement + _old_gen_size_increment_supplement); |
jwilhelm@6085 | 1117 | return align_size_up(result, _space_alignment); |
duke@435 | 1118 | } |
duke@435 | 1119 | |
duke@435 | 1120 | size_t PSAdaptiveSizePolicy::promo_decrement_aligned_down(size_t cur_promo) { |
duke@435 | 1121 | size_t promo_heap_delta = promo_decrement(cur_promo); |
jwilhelm@6085 | 1122 | return align_size_down(promo_heap_delta, _space_alignment); |
duke@435 | 1123 | } |
duke@435 | 1124 | |
duke@435 | 1125 | size_t PSAdaptiveSizePolicy::promo_decrement(size_t cur_promo) { |
duke@435 | 1126 | size_t promo_heap_delta = promo_increment(cur_promo); |
duke@435 | 1127 | promo_heap_delta = promo_heap_delta / AdaptiveSizeDecrementScaleFactor; |
duke@435 | 1128 | return promo_heap_delta; |
duke@435 | 1129 | } |
duke@435 | 1130 | |
jwilhelm@4129 | 1131 | uint PSAdaptiveSizePolicy::compute_survivor_space_size_and_threshold( |
duke@435 | 1132 | bool is_survivor_overflow, |
jwilhelm@4129 | 1133 | uint tenuring_threshold, |
duke@435 | 1134 | size_t survivor_limit) { |
jwilhelm@6085 | 1135 | assert(survivor_limit >= _space_alignment, |
duke@435 | 1136 | "survivor_limit too small"); |
jwilhelm@6085 | 1137 | assert((size_t)align_size_down(survivor_limit, _space_alignment) |
duke@435 | 1138 | == survivor_limit, "survivor_limit not aligned"); |
duke@435 | 1139 | |
duke@435 | 1140 | // This method is called even if the tenuring threshold and survivor |
duke@435 | 1141 | // spaces are not adjusted so that the averages are sampled above. |
duke@435 | 1142 | if (!UsePSAdaptiveSurvivorSizePolicy || |
duke@435 | 1143 | !young_gen_policy_is_ready()) { |
duke@435 | 1144 | return tenuring_threshold; |
duke@435 | 1145 | } |
duke@435 | 1146 | |
duke@435 | 1147 | // We'll decide whether to increase or decrease the tenuring |
duke@435 | 1148 | // threshold based partly on the newly computed survivor size |
duke@435 | 1149 | // (if we hit the maximum limit allowed, we'll always choose to |
duke@435 | 1150 | // decrement the threshold). |
duke@435 | 1151 | bool incr_tenuring_threshold = false; |
duke@435 | 1152 | bool decr_tenuring_threshold = false; |
duke@435 | 1153 | |
duke@435 | 1154 | set_decrement_tenuring_threshold_for_gc_cost(false); |
duke@435 | 1155 | set_increment_tenuring_threshold_for_gc_cost(false); |
duke@435 | 1156 | set_decrement_tenuring_threshold_for_survivor_limit(false); |
duke@435 | 1157 | |
duke@435 | 1158 | if (!is_survivor_overflow) { |
duke@435 | 1159 | // Keep running averages on how much survived |
duke@435 | 1160 | |
duke@435 | 1161 | // We use the tenuring threshold to equalize the cost of major |
duke@435 | 1162 | // and minor collections. |
duke@435 | 1163 | // ThresholdTolerance is used to indicate how sensitive the |
duke@435 | 1164 | // tenuring threshold is to differences in cost betweent the |
duke@435 | 1165 | // collection types. |
duke@435 | 1166 | |
duke@435 | 1167 | // Get the times of interest. This involves a little work, so |
duke@435 | 1168 | // we cache the values here. |
duke@435 | 1169 | const double major_cost = major_gc_cost(); |
duke@435 | 1170 | const double minor_cost = minor_gc_cost(); |
duke@435 | 1171 | |
duke@435 | 1172 | if (minor_cost > major_cost * _threshold_tolerance_percent) { |
duke@435 | 1173 | // Minor times are getting too long; lower the threshold so |
duke@435 | 1174 | // less survives and more is promoted. |
duke@435 | 1175 | decr_tenuring_threshold = true; |
duke@435 | 1176 | set_decrement_tenuring_threshold_for_gc_cost(true); |
duke@435 | 1177 | } else if (major_cost > minor_cost * _threshold_tolerance_percent) { |
duke@435 | 1178 | // Major times are too long, so we want less promotion. |
duke@435 | 1179 | incr_tenuring_threshold = true; |
duke@435 | 1180 | set_increment_tenuring_threshold_for_gc_cost(true); |
duke@435 | 1181 | } |
duke@435 | 1182 | |
duke@435 | 1183 | } else { |
duke@435 | 1184 | // Survivor space overflow occurred, so promoted and survived are |
duke@435 | 1185 | // not accurate. We'll make our best guess by combining survived |
duke@435 | 1186 | // and promoted and count them as survivors. |
duke@435 | 1187 | // |
duke@435 | 1188 | // We'll lower the tenuring threshold to see if we can correct |
duke@435 | 1189 | // things. Also, set the survivor size conservatively. We're |
duke@435 | 1190 | // trying to avoid many overflows from occurring if defnew size |
duke@435 | 1191 | // is just too small. |
duke@435 | 1192 | |
duke@435 | 1193 | decr_tenuring_threshold = true; |
duke@435 | 1194 | } |
duke@435 | 1195 | |
duke@435 | 1196 | // The padded average also maintains a deviation from the average; |
duke@435 | 1197 | // we use this to see how good of an estimate we have of what survived. |
duke@435 | 1198 | // We're trying to pad the survivor size as little as possible without |
duke@435 | 1199 | // overflowing the survivor spaces. |
duke@435 | 1200 | size_t target_size = align_size_up((size_t)_avg_survived->padded_average(), |
jwilhelm@6085 | 1201 | _space_alignment); |
jwilhelm@6085 | 1202 | target_size = MAX2(target_size, _space_alignment); |
duke@435 | 1203 | |
duke@435 | 1204 | if (target_size > survivor_limit) { |
duke@435 | 1205 | // Target size is bigger than we can handle. Let's also reduce |
duke@435 | 1206 | // the tenuring threshold. |
duke@435 | 1207 | target_size = survivor_limit; |
duke@435 | 1208 | decr_tenuring_threshold = true; |
duke@435 | 1209 | set_decrement_tenuring_threshold_for_survivor_limit(true); |
duke@435 | 1210 | } |
duke@435 | 1211 | |
duke@435 | 1212 | // Finally, increment or decrement the tenuring threshold, as decided above. |
duke@435 | 1213 | // We test for decrementing first, as we might have hit the target size |
duke@435 | 1214 | // limit. |
duke@435 | 1215 | if (decr_tenuring_threshold && !(AlwaysTenure || NeverTenure)) { |
duke@435 | 1216 | if (tenuring_threshold > 1) { |
duke@435 | 1217 | tenuring_threshold--; |
duke@435 | 1218 | } |
duke@435 | 1219 | } else if (incr_tenuring_threshold && !(AlwaysTenure || NeverTenure)) { |
duke@435 | 1220 | if (tenuring_threshold < MaxTenuringThreshold) { |
duke@435 | 1221 | tenuring_threshold++; |
duke@435 | 1222 | } |
duke@435 | 1223 | } |
duke@435 | 1224 | |
duke@435 | 1225 | // We keep a running average of the amount promoted which is used |
duke@435 | 1226 | // to decide when we should collect the old generation (when |
duke@435 | 1227 | // the amount of old gen free space is less than what we expect to |
duke@435 | 1228 | // promote). |
duke@435 | 1229 | |
duke@435 | 1230 | if (PrintAdaptiveSizePolicy) { |
duke@435 | 1231 | // A little more detail if Verbose is on |
duke@435 | 1232 | if (Verbose) { |
duke@435 | 1233 | gclog_or_tty->print( " avg_survived: %f" |
duke@435 | 1234 | " avg_deviation: %f", |
duke@435 | 1235 | _avg_survived->average(), |
duke@435 | 1236 | _avg_survived->deviation()); |
duke@435 | 1237 | } |
duke@435 | 1238 | |
duke@435 | 1239 | gclog_or_tty->print( " avg_survived_padded_avg: %f", |
duke@435 | 1240 | _avg_survived->padded_average()); |
duke@435 | 1241 | |
duke@435 | 1242 | if (Verbose) { |
duke@435 | 1243 | gclog_or_tty->print( " avg_promoted_avg: %f" |
duke@435 | 1244 | " avg_promoted_dev: %f", |
duke@435 | 1245 | avg_promoted()->average(), |
duke@435 | 1246 | avg_promoted()->deviation()); |
duke@435 | 1247 | } |
duke@435 | 1248 | |
poonam@5279 | 1249 | gclog_or_tty->print_cr( " avg_promoted_padded_avg: %f" |
duke@435 | 1250 | " avg_pretenured_padded_avg: %f" |
duke@435 | 1251 | " tenuring_thresh: %d" |
duke@435 | 1252 | " target_size: " SIZE_FORMAT, |
duke@435 | 1253 | avg_promoted()->padded_average(), |
duke@435 | 1254 | _avg_pretenured->padded_average(), |
duke@435 | 1255 | tenuring_threshold, target_size); |
duke@435 | 1256 | } |
duke@435 | 1257 | |
duke@435 | 1258 | set_survivor_size(target_size); |
duke@435 | 1259 | |
duke@435 | 1260 | return tenuring_threshold; |
duke@435 | 1261 | } |
duke@435 | 1262 | |
duke@435 | 1263 | void PSAdaptiveSizePolicy::update_averages(bool is_survivor_overflow, |
duke@435 | 1264 | size_t survived, |
duke@435 | 1265 | size_t promoted) { |
duke@435 | 1266 | // Update averages |
duke@435 | 1267 | if (!is_survivor_overflow) { |
duke@435 | 1268 | // Keep running averages on how much survived |
duke@435 | 1269 | _avg_survived->sample(survived); |
duke@435 | 1270 | } else { |
duke@435 | 1271 | size_t survived_guess = survived + promoted; |
duke@435 | 1272 | _avg_survived->sample(survived_guess); |
duke@435 | 1273 | } |
duke@435 | 1274 | avg_promoted()->sample(promoted + _avg_pretenured->padded_average()); |
duke@435 | 1275 | |
duke@435 | 1276 | if (PrintAdaptiveSizePolicy) { |
poonam@5279 | 1277 | gclog_or_tty->print_cr( |
tamao@5192 | 1278 | "AdaptiveSizePolicy::update_averages:" |
duke@435 | 1279 | " survived: " SIZE_FORMAT |
duke@435 | 1280 | " promoted: " SIZE_FORMAT |
duke@435 | 1281 | " overflow: %s", |
duke@435 | 1282 | survived, promoted, is_survivor_overflow ? "true" : "false"); |
duke@435 | 1283 | } |
duke@435 | 1284 | } |
duke@435 | 1285 | |
duke@435 | 1286 | bool PSAdaptiveSizePolicy::print_adaptive_size_policy_on(outputStream* st) |
duke@435 | 1287 | const { |
duke@435 | 1288 | |
duke@435 | 1289 | if (!UseAdaptiveSizePolicy) return false; |
duke@435 | 1290 | |
duke@435 | 1291 | return AdaptiveSizePolicy::print_adaptive_size_policy_on( |
duke@435 | 1292 | st, |
duke@435 | 1293 | PSScavenge::tenuring_threshold()); |
duke@435 | 1294 | } |