rev 11552 : imported patch 8159978-collection-set-as-array

   1 /*
   2  * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_GC_G1_G1DEFAULTPOLICY_HPP
  26 #define SHARE_VM_GC_G1_G1DEFAULTPOLICY_HPP
  27 
  28 #include "gc/g1/g1CollectorState.hpp"
  29 #include "gc/g1/g1GCPhaseTimes.hpp"
  30 #include "gc/g1/g1InCSetState.hpp"
  31 #include "gc/g1/g1InitialMarkToMixedTimeTracker.hpp"
  32 #include "gc/g1/g1MMUTracker.hpp"
  33 #include "gc/g1/g1Predictions.hpp"
  34 #include "gc/g1/g1Policy.hpp"
  35 #include "gc/g1/g1YoungGenSizer.hpp"
  36 #include "gc/shared/gcCause.hpp"
  37 #include "utilities/pair.hpp"
  38 
  39 class HeapRegion;
  40 class G1CollectionSet;
  41 class CollectionSetChooser;
  42 class G1IHOPControl;
  43 class G1Analytics;
  44 class G1SurvivorRegions;
  45 class G1YoungGenSizer;
  46 class GCPolicyCounters;
  47 
  48 class G1DefaultPolicy: public G1Policy {
  49  private:
  50 
  51   static G1IHOPControl* create_ihop_control(const G1Predictions* predictor);
  52   // Update the IHOP control with necessary statistics.
  53   void update_ihop_prediction(double mutator_time_s,
  54                               size_t mutator_alloc_bytes,
  55                               size_t young_gen_size);
  56   void report_ihop_statistics();
  57 
  58   G1Predictions _predictor;
  59   G1Analytics* _analytics;
  60   G1MMUTracker* _mmu_tracker;
  61   G1IHOPControl* _ihop_control;
  62 
  63   GCPolicyCounters* _policy_counters;
  64 
  65   double _full_collection_start_sec;
  66 
  67   uint _young_list_target_length;
  68   uint _young_list_fixed_length;
  69 
  70   // The max number of regions we can extend the eden by while the GC
  71   // locker is active. This should be >= _young_list_target_length;
  72   uint _young_list_max_length;
  73 
  74   // SurvRateGroups below must be initialized after the predictor because they
  75   // indirectly use it through this object passed to their constructor.
  76   SurvRateGroup* _short_lived_surv_rate_group;
  77   SurvRateGroup* _survivor_surv_rate_group;
  78 
  79   double _reserve_factor;
  80   // This will be set when the heap is expanded
  81   // for the first time during initialization.
  82   uint   _reserve_regions;
  83 
  84   G1YoungGenSizer _young_gen_sizer;
  85 
  86   uint _free_regions_at_end_of_collection;
  87 
  88   size_t _max_rs_lengths;
  89 
  90   size_t _rs_lengths_prediction;
  91 
  92 #ifndef PRODUCT
  93   bool verify_young_ages(HeapRegion* head, SurvRateGroup *surv_rate_group);
  94 #endif // PRODUCT
  95 
  96   size_t _pending_cards;
  97 
  98   // The amount of allocated bytes in old gen during the last mutator and the following
  99   // young GC phase.
 100   size_t _bytes_allocated_in_old_since_last_gc;
 101 
 102   G1InitialMarkToMixedTimeTracker _initial_mark_to_mixed;
 103 public:
 104   const G1Predictions& predictor() const { return _predictor; }
 105   const G1Analytics* analytics()   const { return const_cast<const G1Analytics*>(_analytics); }
 106 
 107   void add_bytes_allocated_in_old_since_last_gc(size_t bytes) { _bytes_allocated_in_old_since_last_gc += bytes; }
 108 
 109   void set_region_eden(HeapRegion* hr) {
 110     hr->set_eden();
 111     hr->install_surv_rate_group(_short_lived_surv_rate_group);
 112   }
 113 
 114   void set_region_survivor(HeapRegion* hr) {
 115     assert(hr->is_survivor(), "pre-condition");
 116     hr->install_surv_rate_group(_survivor_surv_rate_group);
 117   }
 118 
 119 #ifndef PRODUCT
 120   bool verify_young_ages();
 121 #endif // PRODUCT
 122 
 123   void record_max_rs_lengths(size_t rs_lengths) {
 124     _max_rs_lengths = rs_lengths;
 125   }
 126 
 127 
 128   double predict_base_elapsed_time_ms(size_t pending_cards) const;
 129   double predict_base_elapsed_time_ms(size_t pending_cards,
 130                                       size_t scanned_cards) const;
 131   size_t predict_bytes_to_copy(HeapRegion* hr) const;
 132   double predict_region_elapsed_time_ms(HeapRegion* hr, bool for_young_gc) const;
 133 
 134   double predict_survivor_regions_evac_time() const;
 135 
 136   bool should_update_surv_rate_group_predictors() {
 137     return collector_state()->last_gc_was_young() && !collector_state()->in_marking_window();
 138   }
 139 
 140   void cset_regions_freed() {
 141     bool update = should_update_surv_rate_group_predictors();
 142 
 143     _short_lived_surv_rate_group->all_surviving_words_recorded(predictor(), update);
 144     _survivor_surv_rate_group->all_surviving_words_recorded(predictor(), update);
 145   }
 146 
 147   G1MMUTracker* mmu_tracker() {
 148     return _mmu_tracker;
 149   }
 150 
 151   const G1MMUTracker* mmu_tracker() const {
 152     return _mmu_tracker;
 153   }
 154 
 155   double max_pause_time_ms() const {
 156     return _mmu_tracker->max_gc_time() * 1000.0;
 157   }
 158 
 159   double predict_yg_surv_rate(int age, SurvRateGroup* surv_rate_group) const;
 160 
 161   double predict_yg_surv_rate(int age) const;
 162 
 163   double accum_yg_surv_rate_pred(int age) const;
 164 
 165 protected:
 166   G1CollectionSet* _collection_set;
 167   virtual double average_time_ms(G1GCPhaseTimes::GCParPhases phase) const;
 168   virtual double other_time_ms(double pause_time_ms) const;
 169 
 170   double young_other_time_ms() const;
 171   double non_young_other_time_ms() const;
 172   double constant_other_time_ms(double pause_time_ms) const;
 173 
 174   CollectionSetChooser* cset_chooser() const;
 175 private:
 176 
 177   // The number of bytes copied during the GC.
 178   size_t _bytes_copied_during_gc;
 179 
 180   // Stash a pointer to the g1 heap.
 181   G1CollectedHeap* _g1;
 182 
 183   G1GCPhaseTimes* _phase_times;
 184 
 185   // This set of variables tracks the collector efficiency, in order to
 186   // determine whether we should initiate a new marking.
 187   double _mark_remark_start_sec;
 188   double _mark_cleanup_start_sec;
 189 
 190   // Updates the internal young list maximum and target lengths. Returns the
 191   // unbounded young list target length.
 192   uint update_young_list_max_and_target_length();
 193   uint update_young_list_max_and_target_length(size_t rs_lengths);
 194 
 195   // Update the young list target length either by setting it to the
 196   // desired fixed value or by calculating it using G1's pause
 197   // prediction model. If no rs_lengths parameter is passed, predict
 198   // the RS lengths using the prediction model, otherwise use the
 199   // given rs_lengths as the prediction.
 200   // Returns the unbounded young list target length.
 201   uint update_young_list_target_length(size_t rs_lengths);
 202 
 203   // Calculate and return the minimum desired young list target
 204   // length. This is the minimum desired young list length according
 205   // to the user's inputs.
 206   uint calculate_young_list_desired_min_length(uint base_min_length) const;
 207 
 208   // Calculate and return the maximum desired young list target
 209   // length. This is the maximum desired young list length according
 210   // to the user's inputs.
 211   uint calculate_young_list_desired_max_length() const;
 212 
 213   // Calculate and return the maximum young list target length that
 214   // can fit into the pause time goal. The parameters are: rs_lengths
 215   // represent the prediction of how large the young RSet lengths will
 216   // be, base_min_length is the already existing number of regions in
 217   // the young list, min_length and max_length are the desired min and
 218   // max young list length according to the user's inputs.
 219   uint calculate_young_list_target_length(size_t rs_lengths,
 220                                           uint base_min_length,
 221                                           uint desired_min_length,
 222                                           uint desired_max_length) const;
 223 
 224   // Result of the bounded_young_list_target_length() method, containing both the
 225   // bounded as well as the unbounded young list target lengths in this order.
 226   typedef Pair<uint, uint, StackObj> YoungTargetLengths;
 227   YoungTargetLengths young_list_target_lengths(size_t rs_lengths) const;
 228 
 229   void update_rs_lengths_prediction();
 230   void update_rs_lengths_prediction(size_t prediction);
 231 
 232   // Check whether a given young length (young_length) fits into the
 233   // given target pause time and whether the prediction for the amount
 234   // of objects to be copied for the given length will fit into the
 235   // given free space (expressed by base_free_regions).  It is used by
 236   // calculate_young_list_target_length().
 237   bool predict_will_fit(uint young_length, double base_time_ms,
 238                         uint base_free_regions, double target_pause_time_ms) const;
 239 
 240 public:
 241   size_t pending_cards() const { return _pending_cards; }
 242 
 243   uint calc_min_old_cset_length() const;
 244   uint calc_max_old_cset_length() const;
 245 
 246   double reclaimable_bytes_perc(size_t reclaimable_bytes) const;
 247 
 248 private:
 249   // Sets up marking if proper conditions are met.
 250   void maybe_start_marking();
 251 
 252   // The kind of STW pause.
 253   enum PauseKind {
 254     FullGC,
 255     YoungOnlyGC,
 256     MixedGC,
 257     LastYoungGC,
 258     InitialMarkGC,
 259     Cleanup,
 260     Remark
 261   };
 262 
 263   // Calculate PauseKind from internal state.
 264   PauseKind young_gc_pause_kind() const;
 265   // Record the given STW pause with the given start and end times (in s).
 266   void record_pause(PauseKind kind, double start, double end);
 267   // Indicate that we aborted marking before doing any mixed GCs.
 268   void abort_time_to_mixed_tracking();
 269 public:
 270 
 271   G1DefaultPolicy();
 272 
 273   virtual ~G1DefaultPolicy();
 274 
 275   G1CollectorState* collector_state() const;
 276 
 277   G1GCPhaseTimes* phase_times() const { return _phase_times; }
 278 
 279   void revise_young_list_target_length_if_necessary(size_t rs_lengths);
 280 
 281   void record_new_heap_size(uint new_number_of_regions);
 282 
 283   void init(G1CollectedHeap* g1h, G1CollectionSet* collection_set);
 284 
 285   virtual void note_gc_start();
 286 
 287   bool need_to_start_conc_mark(const char* source, size_t alloc_word_size = 0);
 288 
 289   bool about_to_start_mixed_phase() const;
 290 
 291   void record_collection_pause_start(double start_time_sec);
 292   void record_collection_pause_end(double pause_time_ms, size_t cards_scanned, size_t heap_used_bytes_before_gc);
 293 
 294   void record_full_collection_start();
 295   void record_full_collection_end();
 296 
 297   void record_concurrent_mark_init_end(double mark_init_elapsed_time_ms);
 298 
 299   void record_concurrent_mark_remark_start();
 300   void record_concurrent_mark_remark_end();
 301 
 302   void record_concurrent_mark_cleanup_start();
 303   void record_concurrent_mark_cleanup_end();
 304   void record_concurrent_mark_cleanup_completed();
 305 
 306   virtual void print_phases();
 307 
 308   void record_bytes_copied_during_gc(size_t bytes) {
 309     _bytes_copied_during_gc += bytes;
 310   }
 311 
 312   size_t bytes_copied_during_gc() const {
 313     return _bytes_copied_during_gc;
 314   }
 315 
 316   bool next_gc_should_be_mixed(const char* true_action_str,
 317                                const char* false_action_str) const;
 318 
 319   virtual void finalize_collection_set(double target_pause_time_ms, G1SurvivorRegions* survivor);
 320 private:
 321   // Set the state to start a concurrent marking cycle and clear
 322   // _initiate_conc_mark_if_possible because it has now been
 323   // acted on.
 324   void initiate_conc_mark();
 325 
 326 public:
 327   bool force_initial_mark_if_outside_cycle(GCCause::Cause gc_cause);
 328 
 329   void decide_on_conc_mark_initiation();
 330 
 331   void finished_recalculating_age_indexes(bool is_survivors) {
 332     if (is_survivors) {
 333       _survivor_surv_rate_group->finished_recalculating_age_indexes();
 334     } else {
 335       _short_lived_surv_rate_group->finished_recalculating_age_indexes();
 336     }
 337   }
 338 
 339   size_t young_list_target_length() const { return _young_list_target_length; }
 340 
 341   bool should_allocate_mutator_region() const;
 342 
 343   bool can_expand_young_list() const;
 344 
 345   uint young_list_max_length() const {
 346     return _young_list_max_length;
 347   }
 348 
 349   bool adaptive_young_list_length() const;
 350 
 351   virtual bool should_process_references() const {
 352     return true;
 353   }
 354 
 355   void transfer_survivors_to_cset(const G1SurvivorRegions* survivors);
 356 
 357 private:
 358   //
 359   // Survivor regions policy.
 360   //
 361 
 362   // Current tenuring threshold, set to 0 if the collector reaches the
 363   // maximum amount of survivors regions.
 364   uint _tenuring_threshold;
 365 
 366   // The limit on the number of regions allocated for survivors.
 367   uint _max_survivor_regions;
 368 
 369   AgeTable _survivors_age_table;
 370 
 371 public:
 372   uint tenuring_threshold() const { return _tenuring_threshold; }
 373 
 374   uint max_survivor_regions() {
 375     return _max_survivor_regions;
 376   }
 377 
 378   void note_start_adding_survivor_regions() {
 379     _survivor_surv_rate_group->start_adding_regions();
 380   }
 381 
 382   void note_stop_adding_survivor_regions() {
 383     _survivor_surv_rate_group->stop_adding_regions();
 384   }
 385 
 386   void record_age_table(AgeTable* age_table) {
 387     _survivors_age_table.merge(age_table);
 388   }
 389 
 390   void update_max_gc_locker_expansion();
 391 
 392   void update_survivors_policy();
 393 };
 394 
 395 #endif // SHARE_VM_GC_G1_G1DEFAULTPOLICY_HPP
--- EOF ---