src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp

Thu, 05 Jun 2008 15:57:56 -0700

author
ysr
date
Thu, 05 Jun 2008 15:57:56 -0700
changeset 777
37f87013dfd8
child 790
0edda524b58c
permissions
-rw-r--r--

6711316: Open source the Garbage-First garbage collector
Summary: First mercurial integration of the code for the Garbage-First garbage collector.
Reviewed-by: apetrusenko, iveresov, jmasa, sgoldman, tonyp, ysr

ysr@777 1 /*
ysr@777 2 * Copyright 2001-2007 Sun Microsystems, Inc. All Rights Reserved.
ysr@777 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
ysr@777 4 *
ysr@777 5 * This code is free software; you can redistribute it and/or modify it
ysr@777 6 * under the terms of the GNU General Public License version 2 only, as
ysr@777 7 * published by the Free Software Foundation.
ysr@777 8 *
ysr@777 9 * This code is distributed in the hope that it will be useful, but WITHOUT
ysr@777 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
ysr@777 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
ysr@777 12 * version 2 for more details (a copy is included in the LICENSE file that
ysr@777 13 * accompanied this code).
ysr@777 14 *
ysr@777 15 * You should have received a copy of the GNU General Public License version
ysr@777 16 * 2 along with this work; if not, write to the Free Software Foundation,
ysr@777 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
ysr@777 18 *
ysr@777 19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
ysr@777 20 * CA 95054 USA or visit www.sun.com if you need additional information or
ysr@777 21 * have any questions.
ysr@777 22 *
ysr@777 23 */
ysr@777 24
ysr@777 25 #include "incls/_precompiled.incl"
ysr@777 26 #include "incls/_g1CollectorPolicy.cpp.incl"
ysr@777 27
ysr@777 28 #define PREDICTIONS_VERBOSE 0
ysr@777 29
ysr@777 30 // <NEW PREDICTION>
ysr@777 31
ysr@777 32 // Different defaults for different number of GC threads
ysr@777 33 // They were chosen by running GCOld and SPECjbb on debris with different
ysr@777 34 // numbers of GC threads and choosing them based on the results
ysr@777 35
ysr@777 36 // all the same
ysr@777 37 static double rs_length_diff_defaults[] = {
ysr@777 38 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0
ysr@777 39 };
ysr@777 40
ysr@777 41 static double cost_per_card_ms_defaults[] = {
ysr@777 42 0.01, 0.005, 0.005, 0.003, 0.003, 0.002, 0.002, 0.0015
ysr@777 43 };
ysr@777 44
ysr@777 45 static double cost_per_scan_only_region_ms_defaults[] = {
ysr@777 46 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0
ysr@777 47 };
ysr@777 48
ysr@777 49 // all the same
ysr@777 50 static double fully_young_cards_per_entry_ratio_defaults[] = {
ysr@777 51 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0
ysr@777 52 };
ysr@777 53
ysr@777 54 static double cost_per_entry_ms_defaults[] = {
ysr@777 55 0.015, 0.01, 0.01, 0.008, 0.008, 0.0055, 0.0055, 0.005
ysr@777 56 };
ysr@777 57
ysr@777 58 static double cost_per_byte_ms_defaults[] = {
ysr@777 59 0.00006, 0.00003, 0.00003, 0.000015, 0.000015, 0.00001, 0.00001, 0.000009
ysr@777 60 };
ysr@777 61
ysr@777 62 // these should be pretty consistent
ysr@777 63 static double constant_other_time_ms_defaults[] = {
ysr@777 64 5.0, 5.0, 5.0, 5.0, 5.0, 5.0, 5.0, 5.0
ysr@777 65 };
ysr@777 66
ysr@777 67
ysr@777 68 static double young_other_cost_per_region_ms_defaults[] = {
ysr@777 69 0.3, 0.2, 0.2, 0.15, 0.15, 0.12, 0.12, 0.1
ysr@777 70 };
ysr@777 71
ysr@777 72 static double non_young_other_cost_per_region_ms_defaults[] = {
ysr@777 73 1.0, 0.7, 0.7, 0.5, 0.5, 0.42, 0.42, 0.30
ysr@777 74 };
ysr@777 75
ysr@777 76 // </NEW PREDICTION>
ysr@777 77
ysr@777 78 G1CollectorPolicy::G1CollectorPolicy() :
ysr@777 79 _parallel_gc_threads((ParallelGCThreads > 0) ? ParallelGCThreads : 1),
ysr@777 80 _n_pauses(0),
ysr@777 81 _recent_CH_strong_roots_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 82 _recent_G1_strong_roots_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 83 _recent_evac_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 84 _recent_pause_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 85 _recent_rs_sizes(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 86 _recent_gc_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 87 _all_pause_times_ms(new NumberSeq()),
ysr@777 88 _stop_world_start(0.0),
ysr@777 89 _all_stop_world_times_ms(new NumberSeq()),
ysr@777 90 _all_yield_times_ms(new NumberSeq()),
ysr@777 91
ysr@777 92 _all_mod_union_times_ms(new NumberSeq()),
ysr@777 93
ysr@777 94 _non_pop_summary(new NonPopSummary()),
ysr@777 95 _pop_summary(new PopSummary()),
ysr@777 96 _non_pop_abandoned_summary(new NonPopAbandonedSummary()),
ysr@777 97 _pop_abandoned_summary(new PopAbandonedSummary()),
ysr@777 98
ysr@777 99 _cur_clear_ct_time_ms(0.0),
ysr@777 100
ysr@777 101 _region_num_young(0),
ysr@777 102 _region_num_tenured(0),
ysr@777 103 _prev_region_num_young(0),
ysr@777 104 _prev_region_num_tenured(0),
ysr@777 105
ysr@777 106 _aux_num(10),
ysr@777 107 _all_aux_times_ms(new NumberSeq[_aux_num]),
ysr@777 108 _cur_aux_start_times_ms(new double[_aux_num]),
ysr@777 109 _cur_aux_times_ms(new double[_aux_num]),
ysr@777 110 _cur_aux_times_set(new bool[_aux_num]),
ysr@777 111
ysr@777 112 _pop_compute_rc_start(0.0),
ysr@777 113 _pop_evac_start(0.0),
ysr@777 114
ysr@777 115 _concurrent_mark_init_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 116 _concurrent_mark_remark_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 117 _concurrent_mark_cleanup_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 118
ysr@777 119 // <NEW PREDICTION>
ysr@777 120
ysr@777 121 _alloc_rate_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 122 _prev_collection_pause_end_ms(0.0),
ysr@777 123 _pending_card_diff_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 124 _rs_length_diff_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 125 _cost_per_card_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 126 _cost_per_scan_only_region_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 127 _fully_young_cards_per_entry_ratio_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 128 _partially_young_cards_per_entry_ratio_seq(
ysr@777 129 new TruncatedSeq(TruncatedSeqLength)),
ysr@777 130 _cost_per_entry_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 131 _partially_young_cost_per_entry_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 132 _cost_per_byte_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 133 _cost_per_byte_ms_during_cm_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 134 _cost_per_scan_only_region_ms_during_cm_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 135 _constant_other_time_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 136 _young_other_cost_per_region_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 137 _non_young_other_cost_per_region_ms_seq(
ysr@777 138 new TruncatedSeq(TruncatedSeqLength)),
ysr@777 139
ysr@777 140 _pending_cards_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 141 _scanned_cards_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 142 _rs_lengths_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 143
ysr@777 144 _pause_time_target_ms((double) G1MaxPauseTimeMS),
ysr@777 145
ysr@777 146 // </NEW PREDICTION>
ysr@777 147
ysr@777 148 _in_young_gc_mode(false),
ysr@777 149 _full_young_gcs(true),
ysr@777 150 _full_young_pause_num(0),
ysr@777 151 _partial_young_pause_num(0),
ysr@777 152
ysr@777 153 _during_marking(false),
ysr@777 154 _in_marking_window(false),
ysr@777 155 _in_marking_window_im(false),
ysr@777 156
ysr@777 157 _known_garbage_ratio(0.0),
ysr@777 158 _known_garbage_bytes(0),
ysr@777 159
ysr@777 160 _young_gc_eff_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 161 _target_pause_time_ms(-1.0),
ysr@777 162
ysr@777 163 _recent_prev_end_times_for_all_gcs_sec(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 164
ysr@777 165 _recent_CS_bytes_used_before(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 166 _recent_CS_bytes_surviving(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 167
ysr@777 168 _recent_avg_pause_time_ratio(0.0),
ysr@777 169 _num_markings(0),
ysr@777 170 _n_marks(0),
ysr@777 171 _n_pauses_at_mark_end(0),
ysr@777 172
ysr@777 173 _all_full_gc_times_ms(new NumberSeq()),
ysr@777 174
ysr@777 175 _conc_refine_enabled(0),
ysr@777 176 _conc_refine_zero_traversals(0),
ysr@777 177 _conc_refine_max_traversals(0),
ysr@777 178 _conc_refine_current_delta(G1ConcRefineInitialDelta),
ysr@777 179
ysr@777 180 // G1PausesBtwnConcMark defaults to -1
ysr@777 181 // so the hack is to do the cast QQQ FIXME
ysr@777 182 _pauses_btwn_concurrent_mark((size_t)G1PausesBtwnConcMark),
ysr@777 183 _n_marks_since_last_pause(0),
ysr@777 184 _conc_mark_initiated(false),
ysr@777 185 _should_initiate_conc_mark(false),
ysr@777 186 _should_revert_to_full_young_gcs(false),
ysr@777 187 _last_full_young_gc(false),
ysr@777 188
ysr@777 189 _prev_collection_pause_used_at_end_bytes(0),
ysr@777 190
ysr@777 191 _collection_set(NULL),
ysr@777 192 #ifdef _MSC_VER // the use of 'this' below gets a warning, make it go away
ysr@777 193 #pragma warning( disable:4355 ) // 'this' : used in base member initializer list
ysr@777 194 #endif // _MSC_VER
ysr@777 195
ysr@777 196 _short_lived_surv_rate_group(new SurvRateGroup(this, "Short Lived",
ysr@777 197 G1YoungSurvRateNumRegionsSummary)),
ysr@777 198 _survivor_surv_rate_group(new SurvRateGroup(this, "Survivor",
ysr@777 199 G1YoungSurvRateNumRegionsSummary))
ysr@777 200 // add here any more surv rate groups
ysr@777 201 {
ysr@777 202 _recent_prev_end_times_for_all_gcs_sec->add(os::elapsedTime());
ysr@777 203 _prev_collection_pause_end_ms = os::elapsedTime() * 1000.0;
ysr@777 204
ysr@777 205 _par_last_ext_root_scan_times_ms = new double[_parallel_gc_threads];
ysr@777 206 _par_last_mark_stack_scan_times_ms = new double[_parallel_gc_threads];
ysr@777 207 _par_last_scan_only_times_ms = new double[_parallel_gc_threads];
ysr@777 208 _par_last_scan_only_regions_scanned = new double[_parallel_gc_threads];
ysr@777 209
ysr@777 210 _par_last_update_rs_start_times_ms = new double[_parallel_gc_threads];
ysr@777 211 _par_last_update_rs_times_ms = new double[_parallel_gc_threads];
ysr@777 212 _par_last_update_rs_processed_buffers = new double[_parallel_gc_threads];
ysr@777 213
ysr@777 214 _par_last_scan_rs_start_times_ms = new double[_parallel_gc_threads];
ysr@777 215 _par_last_scan_rs_times_ms = new double[_parallel_gc_threads];
ysr@777 216 _par_last_scan_new_refs_times_ms = new double[_parallel_gc_threads];
ysr@777 217
ysr@777 218 _par_last_obj_copy_times_ms = new double[_parallel_gc_threads];
ysr@777 219
ysr@777 220 _par_last_termination_times_ms = new double[_parallel_gc_threads];
ysr@777 221
ysr@777 222 // we store the data from the first pass during popularity pauses
ysr@777 223 _pop_par_last_update_rs_start_times_ms = new double[_parallel_gc_threads];
ysr@777 224 _pop_par_last_update_rs_times_ms = new double[_parallel_gc_threads];
ysr@777 225 _pop_par_last_update_rs_processed_buffers = new double[_parallel_gc_threads];
ysr@777 226
ysr@777 227 _pop_par_last_scan_rs_start_times_ms = new double[_parallel_gc_threads];
ysr@777 228 _pop_par_last_scan_rs_times_ms = new double[_parallel_gc_threads];
ysr@777 229
ysr@777 230 _pop_par_last_closure_app_times_ms = new double[_parallel_gc_threads];
ysr@777 231
ysr@777 232 // start conservatively
ysr@777 233 _expensive_region_limit_ms = 0.5 * (double) G1MaxPauseTimeMS;
ysr@777 234
ysr@777 235 // <NEW PREDICTION>
ysr@777 236
ysr@777 237 int index;
ysr@777 238 if (ParallelGCThreads == 0)
ysr@777 239 index = 0;
ysr@777 240 else if (ParallelGCThreads > 8)
ysr@777 241 index = 7;
ysr@777 242 else
ysr@777 243 index = ParallelGCThreads - 1;
ysr@777 244
ysr@777 245 _pending_card_diff_seq->add(0.0);
ysr@777 246 _rs_length_diff_seq->add(rs_length_diff_defaults[index]);
ysr@777 247 _cost_per_card_ms_seq->add(cost_per_card_ms_defaults[index]);
ysr@777 248 _cost_per_scan_only_region_ms_seq->add(
ysr@777 249 cost_per_scan_only_region_ms_defaults[index]);
ysr@777 250 _fully_young_cards_per_entry_ratio_seq->add(
ysr@777 251 fully_young_cards_per_entry_ratio_defaults[index]);
ysr@777 252 _cost_per_entry_ms_seq->add(cost_per_entry_ms_defaults[index]);
ysr@777 253 _cost_per_byte_ms_seq->add(cost_per_byte_ms_defaults[index]);
ysr@777 254 _constant_other_time_ms_seq->add(constant_other_time_ms_defaults[index]);
ysr@777 255 _young_other_cost_per_region_ms_seq->add(
ysr@777 256 young_other_cost_per_region_ms_defaults[index]);
ysr@777 257 _non_young_other_cost_per_region_ms_seq->add(
ysr@777 258 non_young_other_cost_per_region_ms_defaults[index]);
ysr@777 259
ysr@777 260 // </NEW PREDICTION>
ysr@777 261
ysr@777 262 double time_slice = (double) G1TimeSliceMS / 1000.0;
ysr@777 263 double max_gc_time = (double) G1MaxPauseTimeMS / 1000.0;
ysr@777 264 guarantee(max_gc_time < time_slice,
ysr@777 265 "Max GC time should not be greater than the time slice");
ysr@777 266 _mmu_tracker = new G1MMUTrackerQueue(time_slice, max_gc_time);
ysr@777 267 _sigma = (double) G1ConfidencePerc / 100.0;
ysr@777 268
ysr@777 269 // start conservatively (around 50ms is about right)
ysr@777 270 _concurrent_mark_init_times_ms->add(0.05);
ysr@777 271 _concurrent_mark_remark_times_ms->add(0.05);
ysr@777 272 _concurrent_mark_cleanup_times_ms->add(0.20);
ysr@777 273 _tenuring_threshold = MaxTenuringThreshold;
ysr@777 274
ysr@777 275 initialize_all();
ysr@777 276 }
ysr@777 277
ysr@777 278 // Increment "i", mod "len"
ysr@777 279 static void inc_mod(int& i, int len) {
ysr@777 280 i++; if (i == len) i = 0;
ysr@777 281 }
ysr@777 282
ysr@777 283 void G1CollectorPolicy::initialize_flags() {
ysr@777 284 set_min_alignment(HeapRegion::GrainBytes);
ysr@777 285 set_max_alignment(GenRemSet::max_alignment_constraint(rem_set_name()));
ysr@777 286 CollectorPolicy::initialize_flags();
ysr@777 287 }
ysr@777 288
ysr@777 289 void G1CollectorPolicy::init() {
ysr@777 290 // Set aside an initial future to_space.
ysr@777 291 _g1 = G1CollectedHeap::heap();
ysr@777 292 size_t regions = Universe::heap()->capacity() / HeapRegion::GrainBytes;
ysr@777 293
ysr@777 294 assert(Heap_lock->owned_by_self(), "Locking discipline.");
ysr@777 295
ysr@777 296 if (G1SteadyStateUsed < 50) {
ysr@777 297 vm_exit_during_initialization("G1SteadyStateUsed must be at least 50%.");
ysr@777 298 }
ysr@777 299 if (UseConcMarkSweepGC) {
ysr@777 300 vm_exit_during_initialization("-XX:+UseG1GC is incompatible with "
ysr@777 301 "-XX:+UseConcMarkSweepGC.");
ysr@777 302 }
ysr@777 303
ysr@777 304 if (G1Gen) {
ysr@777 305 _in_young_gc_mode = true;
ysr@777 306
ysr@777 307 if (G1YoungGenSize == 0) {
ysr@777 308 set_adaptive_young_list_length(true);
ysr@777 309 _young_list_fixed_length = 0;
ysr@777 310 } else {
ysr@777 311 set_adaptive_young_list_length(false);
ysr@777 312 _young_list_fixed_length = (G1YoungGenSize / HeapRegion::GrainBytes);
ysr@777 313 }
ysr@777 314 _free_regions_at_end_of_collection = _g1->free_regions();
ysr@777 315 _scan_only_regions_at_end_of_collection = 0;
ysr@777 316 calculate_young_list_min_length();
ysr@777 317 guarantee( _young_list_min_length == 0, "invariant, not enough info" );
ysr@777 318 calculate_young_list_target_config();
ysr@777 319 } else {
ysr@777 320 _young_list_fixed_length = 0;
ysr@777 321 _in_young_gc_mode = false;
ysr@777 322 }
ysr@777 323 }
ysr@777 324
ysr@777 325 void G1CollectorPolicy::calculate_young_list_min_length() {
ysr@777 326 _young_list_min_length = 0;
ysr@777 327
ysr@777 328 if (!adaptive_young_list_length())
ysr@777 329 return;
ysr@777 330
ysr@777 331 if (_alloc_rate_ms_seq->num() > 3) {
ysr@777 332 double now_sec = os::elapsedTime();
ysr@777 333 double when_ms = _mmu_tracker->when_max_gc_sec(now_sec) * 1000.0;
ysr@777 334 double alloc_rate_ms = predict_alloc_rate_ms();
ysr@777 335 int min_regions = (int) ceil(alloc_rate_ms * when_ms);
ysr@777 336 int current_region_num = (int) _g1->young_list_length();
ysr@777 337 _young_list_min_length = min_regions + current_region_num;
ysr@777 338 }
ysr@777 339 }
ysr@777 340
ysr@777 341 void G1CollectorPolicy::calculate_young_list_target_config() {
ysr@777 342 if (adaptive_young_list_length()) {
ysr@777 343 size_t rs_lengths = (size_t) get_new_prediction(_rs_lengths_seq);
ysr@777 344 calculate_young_list_target_config(rs_lengths);
ysr@777 345 } else {
ysr@777 346 if (full_young_gcs())
ysr@777 347 _young_list_target_length = _young_list_fixed_length;
ysr@777 348 else
ysr@777 349 _young_list_target_length = _young_list_fixed_length / 2;
ysr@777 350 _young_list_target_length = MAX2(_young_list_target_length, (size_t)1);
ysr@777 351 size_t so_length = calculate_optimal_so_length(_young_list_target_length);
ysr@777 352 guarantee( so_length < _young_list_target_length, "invariant" );
ysr@777 353 _young_list_so_prefix_length = so_length;
ysr@777 354 }
ysr@777 355 }
ysr@777 356
ysr@777 357 // This method calculate the optimal scan-only set for a fixed young
ysr@777 358 // gen size. I couldn't work out how to reuse the more elaborate one,
ysr@777 359 // i.e. calculate_young_list_target_config(rs_length), as the loops are
ysr@777 360 // fundamentally different (the other one finds a config for different
ysr@777 361 // S-O lengths, whereas here we need to do the opposite).
ysr@777 362 size_t G1CollectorPolicy::calculate_optimal_so_length(
ysr@777 363 size_t young_list_length) {
ysr@777 364 if (!G1UseScanOnlyPrefix)
ysr@777 365 return 0;
ysr@777 366
ysr@777 367 if (_all_pause_times_ms->num() < 3) {
ysr@777 368 // we won't use a scan-only set at the beginning to allow the rest
ysr@777 369 // of the predictors to warm up
ysr@777 370 return 0;
ysr@777 371 }
ysr@777 372
ysr@777 373 if (_cost_per_scan_only_region_ms_seq->num() < 3) {
ysr@777 374 // then, we'll only set the S-O set to 1 for a little bit of time,
ysr@777 375 // to get enough information on the scanning cost
ysr@777 376 return 1;
ysr@777 377 }
ysr@777 378
ysr@777 379 size_t pending_cards = (size_t) get_new_prediction(_pending_cards_seq);
ysr@777 380 size_t rs_lengths = (size_t) get_new_prediction(_rs_lengths_seq);
ysr@777 381 size_t adj_rs_lengths = rs_lengths + predict_rs_length_diff();
ysr@777 382 size_t scanned_cards;
ysr@777 383 if (full_young_gcs())
ysr@777 384 scanned_cards = predict_young_card_num(adj_rs_lengths);
ysr@777 385 else
ysr@777 386 scanned_cards = predict_non_young_card_num(adj_rs_lengths);
ysr@777 387 double base_time_ms = predict_base_elapsed_time_ms(pending_cards,
ysr@777 388 scanned_cards);
ysr@777 389
ysr@777 390 size_t so_length = 0;
ysr@777 391 double max_gc_eff = 0.0;
ysr@777 392 for (size_t i = 0; i < young_list_length; ++i) {
ysr@777 393 double gc_eff = 0.0;
ysr@777 394 double pause_time_ms = 0.0;
ysr@777 395 predict_gc_eff(young_list_length, i, base_time_ms,
ysr@777 396 &gc_eff, &pause_time_ms);
ysr@777 397 if (gc_eff > max_gc_eff) {
ysr@777 398 max_gc_eff = gc_eff;
ysr@777 399 so_length = i;
ysr@777 400 }
ysr@777 401 }
ysr@777 402
ysr@777 403 // set it to 95% of the optimal to make sure we sample the "area"
ysr@777 404 // around the optimal length to get up-to-date survival rate data
ysr@777 405 return so_length * 950 / 1000;
ysr@777 406 }
ysr@777 407
ysr@777 408 // This is a really cool piece of code! It finds the best
ysr@777 409 // target configuration (young length / scan-only prefix length) so
ysr@777 410 // that GC efficiency is maximized and that we also meet a pause
ysr@777 411 // time. It's a triple nested loop. These loops are explained below
ysr@777 412 // from the inside-out :-)
ysr@777 413 //
ysr@777 414 // (a) The innermost loop will try to find the optimal young length
ysr@777 415 // for a fixed S-O length. It uses a binary search to speed up the
ysr@777 416 // process. We assume that, for a fixed S-O length, as we add more
ysr@777 417 // young regions to the CSet, the GC efficiency will only go up (I'll
ysr@777 418 // skip the proof). So, using a binary search to optimize this process
ysr@777 419 // makes perfect sense.
ysr@777 420 //
ysr@777 421 // (b) The middle loop will fix the S-O length before calling the
ysr@777 422 // innermost one. It will vary it between two parameters, increasing
ysr@777 423 // it by a given increment.
ysr@777 424 //
ysr@777 425 // (c) The outermost loop will call the middle loop three times.
ysr@777 426 // (1) The first time it will explore all possible S-O length values
ysr@777 427 // from 0 to as large as it can get, using a coarse increment (to
ysr@777 428 // quickly "home in" to where the optimal seems to be).
ysr@777 429 // (2) The second time it will explore the values around the optimal
ysr@777 430 // that was found by the first iteration using a fine increment.
ysr@777 431 // (3) Once the optimal config has been determined by the second
ysr@777 432 // iteration, we'll redo the calculation, but setting the S-O length
ysr@777 433 // to 95% of the optimal to make sure we sample the "area"
ysr@777 434 // around the optimal length to get up-to-date survival rate data
ysr@777 435 //
ysr@777 436 // Termination conditions for the iterations are several: the pause
ysr@777 437 // time is over the limit, we do not have enough to-space, etc.
ysr@777 438
ysr@777 439 void G1CollectorPolicy::calculate_young_list_target_config(size_t rs_lengths) {
ysr@777 440 guarantee( adaptive_young_list_length(), "pre-condition" );
ysr@777 441
ysr@777 442 double start_time_sec = os::elapsedTime();
ysr@777 443 size_t min_reserve_perc = MAX2((size_t)2, (size_t)G1MinReservePerc);
ysr@777 444 min_reserve_perc = MIN2((size_t) 50, min_reserve_perc);
ysr@777 445 size_t reserve_regions =
ysr@777 446 (size_t) ((double) min_reserve_perc * (double) _g1->n_regions() / 100.0);
ysr@777 447
ysr@777 448 if (full_young_gcs() && _free_regions_at_end_of_collection > 0) {
ysr@777 449 // we are in fully-young mode and there are free regions in the heap
ysr@777 450
ysr@777 451 size_t min_so_length = 0;
ysr@777 452 size_t max_so_length = 0;
ysr@777 453
ysr@777 454 if (G1UseScanOnlyPrefix) {
ysr@777 455 if (_all_pause_times_ms->num() < 3) {
ysr@777 456 // we won't use a scan-only set at the beginning to allow the rest
ysr@777 457 // of the predictors to warm up
ysr@777 458 min_so_length = 0;
ysr@777 459 max_so_length = 0;
ysr@777 460 } else if (_cost_per_scan_only_region_ms_seq->num() < 3) {
ysr@777 461 // then, we'll only set the S-O set to 1 for a little bit of time,
ysr@777 462 // to get enough information on the scanning cost
ysr@777 463 min_so_length = 1;
ysr@777 464 max_so_length = 1;
ysr@777 465 } else if (_in_marking_window || _last_full_young_gc) {
ysr@777 466 // no S-O prefix during a marking phase either, as at the end
ysr@777 467 // of the marking phase we'll have to use a very small young
ysr@777 468 // length target to fill up the rest of the CSet with
ysr@777 469 // non-young regions and, if we have lots of scan-only regions
ysr@777 470 // left-over, we will not be able to add any more non-young
ysr@777 471 // regions.
ysr@777 472 min_so_length = 0;
ysr@777 473 max_so_length = 0;
ysr@777 474 } else {
ysr@777 475 // this is the common case; we'll never reach the maximum, we
ysr@777 476 // one of the end conditions will fire well before that
ysr@777 477 // (hopefully!)
ysr@777 478 min_so_length = 0;
ysr@777 479 max_so_length = _free_regions_at_end_of_collection - 1;
ysr@777 480 }
ysr@777 481 } else {
ysr@777 482 // no S-O prefix, as the switch is not set, but we still need to
ysr@777 483 // do one iteration to calculate the best young target that
ysr@777 484 // meets the pause time; this way we reuse the same code instead
ysr@777 485 // of replicating it
ysr@777 486 min_so_length = 0;
ysr@777 487 max_so_length = 0;
ysr@777 488 }
ysr@777 489
ysr@777 490 double target_pause_time_ms = _mmu_tracker->max_gc_time() * 1000.0;
ysr@777 491 size_t pending_cards = (size_t) get_new_prediction(_pending_cards_seq);
ysr@777 492 size_t adj_rs_lengths = rs_lengths + predict_rs_length_diff();
ysr@777 493 size_t scanned_cards;
ysr@777 494 if (full_young_gcs())
ysr@777 495 scanned_cards = predict_young_card_num(adj_rs_lengths);
ysr@777 496 else
ysr@777 497 scanned_cards = predict_non_young_card_num(adj_rs_lengths);
ysr@777 498 // calculate this once, so that we don't have to recalculate it in
ysr@777 499 // the innermost loop
ysr@777 500 double base_time_ms = predict_base_elapsed_time_ms(pending_cards,
ysr@777 501 scanned_cards);
ysr@777 502
ysr@777 503 // the result
ysr@777 504 size_t final_young_length = 0;
ysr@777 505 size_t final_so_length = 0;
ysr@777 506 double final_gc_eff = 0.0;
ysr@777 507 // we'll also keep track of how many times we go into the inner loop
ysr@777 508 // this is for profiling reasons
ysr@777 509 size_t calculations = 0;
ysr@777 510
ysr@777 511 // this determines which of the three iterations the outer loop is in
ysr@777 512 typedef enum {
ysr@777 513 pass_type_coarse,
ysr@777 514 pass_type_fine,
ysr@777 515 pass_type_final
ysr@777 516 } pass_type_t;
ysr@777 517
ysr@777 518 // range of the outer loop's iteration
ysr@777 519 size_t from_so_length = min_so_length;
ysr@777 520 size_t to_so_length = max_so_length;
ysr@777 521 guarantee( from_so_length <= to_so_length, "invariant" );
ysr@777 522
ysr@777 523 // this will keep the S-O length that's found by the second
ysr@777 524 // iteration of the outer loop; we'll keep it just in case the third
ysr@777 525 // iteration fails to find something
ysr@777 526 size_t fine_so_length = 0;
ysr@777 527
ysr@777 528 // the increment step for the coarse (first) iteration
ysr@777 529 size_t so_coarse_increments = 5;
ysr@777 530
ysr@777 531 // the common case, we'll start with the coarse iteration
ysr@777 532 pass_type_t pass = pass_type_coarse;
ysr@777 533 size_t so_length_incr = so_coarse_increments;
ysr@777 534
ysr@777 535 if (from_so_length == to_so_length) {
ysr@777 536 // not point in doing the coarse iteration, we'll go directly into
ysr@777 537 // the fine one (we essentially trying to find the optimal young
ysr@777 538 // length for a fixed S-O length).
ysr@777 539 so_length_incr = 1;
ysr@777 540 pass = pass_type_final;
ysr@777 541 } else if (to_so_length - from_so_length < 3 * so_coarse_increments) {
ysr@777 542 // again, the range is too short so no point in foind the coarse
ysr@777 543 // iteration either
ysr@777 544 so_length_incr = 1;
ysr@777 545 pass = pass_type_fine;
ysr@777 546 }
ysr@777 547
ysr@777 548 bool done = false;
ysr@777 549 // this is the outermost loop
ysr@777 550 while (!done) {
ysr@777 551 #if 0
ysr@777 552 // leave this in for debugging, just in case
ysr@777 553 gclog_or_tty->print_cr("searching between " SIZE_FORMAT " and " SIZE_FORMAT
ysr@777 554 ", incr " SIZE_FORMAT ", pass %s",
ysr@777 555 from_so_length, to_so_length, so_length_incr,
ysr@777 556 (pass == pass_type_coarse) ? "coarse" :
ysr@777 557 (pass == pass_type_fine) ? "fine" : "final");
ysr@777 558 #endif // 0
ysr@777 559
ysr@777 560 size_t so_length = from_so_length;
ysr@777 561 size_t init_free_regions =
ysr@777 562 MAX2((size_t)0,
ysr@777 563 _free_regions_at_end_of_collection +
ysr@777 564 _scan_only_regions_at_end_of_collection - reserve_regions);
ysr@777 565
ysr@777 566 // this determines whether a configuration was found
ysr@777 567 bool gc_eff_set = false;
ysr@777 568 // this is the middle loop
ysr@777 569 while (so_length <= to_so_length) {
ysr@777 570 // base time, which excludes region-related time; again we
ysr@777 571 // calculate it once to avoid recalculating it in the
ysr@777 572 // innermost loop
ysr@777 573 double base_time_with_so_ms =
ysr@777 574 base_time_ms + predict_scan_only_time_ms(so_length);
ysr@777 575 // it's already over the pause target, go around
ysr@777 576 if (base_time_with_so_ms > target_pause_time_ms)
ysr@777 577 break;
ysr@777 578
ysr@777 579 size_t starting_young_length = so_length+1;
ysr@777 580
ysr@777 581 // we make sure that the short young length that makes sense
ysr@777 582 // (one more than the S-O length) is feasible
ysr@777 583 size_t min_young_length = starting_young_length;
ysr@777 584 double min_gc_eff;
ysr@777 585 bool min_ok;
ysr@777 586 ++calculations;
ysr@777 587 min_ok = predict_gc_eff(min_young_length, so_length,
ysr@777 588 base_time_with_so_ms,
ysr@777 589 init_free_regions, target_pause_time_ms,
ysr@777 590 &min_gc_eff);
ysr@777 591
ysr@777 592 if (min_ok) {
ysr@777 593 // the shortest young length is indeed feasible; we'll know
ysr@777 594 // set up the max young length and we'll do a binary search
ysr@777 595 // between min_young_length and max_young_length
ysr@777 596 size_t max_young_length = _free_regions_at_end_of_collection - 1;
ysr@777 597 double max_gc_eff = 0.0;
ysr@777 598 bool max_ok = false;
ysr@777 599
ysr@777 600 // the innermost loop! (finally!)
ysr@777 601 while (max_young_length > min_young_length) {
ysr@777 602 // we'll make sure that min_young_length is always at a
ysr@777 603 // feasible config
ysr@777 604 guarantee( min_ok, "invariant" );
ysr@777 605
ysr@777 606 ++calculations;
ysr@777 607 max_ok = predict_gc_eff(max_young_length, so_length,
ysr@777 608 base_time_with_so_ms,
ysr@777 609 init_free_regions, target_pause_time_ms,
ysr@777 610 &max_gc_eff);
ysr@777 611
ysr@777 612 size_t diff = (max_young_length - min_young_length) / 2;
ysr@777 613 if (max_ok) {
ysr@777 614 min_young_length = max_young_length;
ysr@777 615 min_gc_eff = max_gc_eff;
ysr@777 616 min_ok = true;
ysr@777 617 }
ysr@777 618 max_young_length = min_young_length + diff;
ysr@777 619 }
ysr@777 620
ysr@777 621 // the innermost loop found a config
ysr@777 622 guarantee( min_ok, "invariant" );
ysr@777 623 if (min_gc_eff > final_gc_eff) {
ysr@777 624 // it's the best config so far, so we'll keep it
ysr@777 625 final_gc_eff = min_gc_eff;
ysr@777 626 final_young_length = min_young_length;
ysr@777 627 final_so_length = so_length;
ysr@777 628 gc_eff_set = true;
ysr@777 629 }
ysr@777 630 }
ysr@777 631
ysr@777 632 // incremental the fixed S-O length and go around
ysr@777 633 so_length += so_length_incr;
ysr@777 634 }
ysr@777 635
ysr@777 636 // this is the end of the outermost loop and we need to decide
ysr@777 637 // what to do during the next iteration
ysr@777 638 if (pass == pass_type_coarse) {
ysr@777 639 // we just did the coarse pass (first iteration)
ysr@777 640
ysr@777 641 if (!gc_eff_set)
ysr@777 642 // we didn't find a feasible config so we'll just bail out; of
ysr@777 643 // course, it might be the case that we missed it; but I'd say
ysr@777 644 // it's a bit unlikely
ysr@777 645 done = true;
ysr@777 646 else {
ysr@777 647 // We did find a feasible config with optimal GC eff during
ysr@777 648 // the first pass. So the second pass we'll only consider the
ysr@777 649 // S-O lengths around that config with a fine increment.
ysr@777 650
ysr@777 651 guarantee( so_length_incr == so_coarse_increments, "invariant" );
ysr@777 652 guarantee( final_so_length >= min_so_length, "invariant" );
ysr@777 653
ysr@777 654 #if 0
ysr@777 655 // leave this in for debugging, just in case
ysr@777 656 gclog_or_tty->print_cr(" coarse pass: SO length " SIZE_FORMAT,
ysr@777 657 final_so_length);
ysr@777 658 #endif // 0
ysr@777 659
ysr@777 660 from_so_length =
ysr@777 661 (final_so_length - min_so_length > so_coarse_increments) ?
ysr@777 662 final_so_length - so_coarse_increments + 1 : min_so_length;
ysr@777 663 to_so_length =
ysr@777 664 (max_so_length - final_so_length > so_coarse_increments) ?
ysr@777 665 final_so_length + so_coarse_increments - 1 : max_so_length;
ysr@777 666
ysr@777 667 pass = pass_type_fine;
ysr@777 668 so_length_incr = 1;
ysr@777 669 }
ysr@777 670 } else if (pass == pass_type_fine) {
ysr@777 671 // we just finished the second pass
ysr@777 672
ysr@777 673 if (!gc_eff_set) {
ysr@777 674 // we didn't find a feasible config (yes, it's possible;
ysr@777 675 // notice that, sometimes, we go directly into the fine
ysr@777 676 // iteration and skip the coarse one) so we bail out
ysr@777 677 done = true;
ysr@777 678 } else {
ysr@777 679 // We did find a feasible config with optimal GC eff
ysr@777 680 guarantee( so_length_incr == 1, "invariant" );
ysr@777 681
ysr@777 682 if (final_so_length == 0) {
ysr@777 683 // The config is of an empty S-O set, so we'll just bail out
ysr@777 684 done = true;
ysr@777 685 } else {
ysr@777 686 // we'll go around once more, setting the S-O length to 95%
ysr@777 687 // of the optimal
ysr@777 688 size_t new_so_length = 950 * final_so_length / 1000;
ysr@777 689
ysr@777 690 #if 0
ysr@777 691 // leave this in for debugging, just in case
ysr@777 692 gclog_or_tty->print_cr(" fine pass: SO length " SIZE_FORMAT
ysr@777 693 ", setting it to " SIZE_FORMAT,
ysr@777 694 final_so_length, new_so_length);
ysr@777 695 #endif // 0
ysr@777 696
ysr@777 697 from_so_length = new_so_length;
ysr@777 698 to_so_length = new_so_length;
ysr@777 699 fine_so_length = final_so_length;
ysr@777 700
ysr@777 701 pass = pass_type_final;
ysr@777 702 }
ysr@777 703 }
ysr@777 704 } else if (pass == pass_type_final) {
ysr@777 705 // we just finished the final (third) pass
ysr@777 706
ysr@777 707 if (!gc_eff_set)
ysr@777 708 // we didn't find a feasible config, so we'll just use the one
ysr@777 709 // we found during the second pass, which we saved
ysr@777 710 final_so_length = fine_so_length;
ysr@777 711
ysr@777 712 // and we're done!
ysr@777 713 done = true;
ysr@777 714 } else {
ysr@777 715 guarantee( false, "should never reach here" );
ysr@777 716 }
ysr@777 717
ysr@777 718 // we now go around the outermost loop
ysr@777 719 }
ysr@777 720
ysr@777 721 // we should have at least one region in the target young length
ysr@777 722 _young_list_target_length = MAX2((size_t) 1, final_young_length);
ysr@777 723 if (final_so_length >= final_young_length)
ysr@777 724 // and we need to ensure that the S-O length is not greater than
ysr@777 725 // the target young length (this is being a bit careful)
ysr@777 726 final_so_length = 0;
ysr@777 727 _young_list_so_prefix_length = final_so_length;
ysr@777 728 guarantee( !_in_marking_window || !_last_full_young_gc ||
ysr@777 729 _young_list_so_prefix_length == 0, "invariant" );
ysr@777 730
ysr@777 731 // let's keep an eye of how long we spend on this calculation
ysr@777 732 // right now, I assume that we'll print it when we need it; we
ysr@777 733 // should really adde it to the breakdown of a pause
ysr@777 734 double end_time_sec = os::elapsedTime();
ysr@777 735 double elapsed_time_ms = (end_time_sec - start_time_sec) * 1000.0;
ysr@777 736
ysr@777 737 #if 0
ysr@777 738 // leave this in for debugging, just in case
ysr@777 739 gclog_or_tty->print_cr("target = %1.1lf ms, young = " SIZE_FORMAT
ysr@777 740 ", SO = " SIZE_FORMAT ", "
ysr@777 741 "elapsed %1.2lf ms, calcs: " SIZE_FORMAT " (%s%s) "
ysr@777 742 SIZE_FORMAT SIZE_FORMAT,
ysr@777 743 target_pause_time_ms,
ysr@777 744 _young_list_target_length - _young_list_so_prefix_length,
ysr@777 745 _young_list_so_prefix_length,
ysr@777 746 elapsed_time_ms,
ysr@777 747 calculations,
ysr@777 748 full_young_gcs() ? "full" : "partial",
ysr@777 749 should_initiate_conc_mark() ? " i-m" : "",
ysr@777 750 in_marking_window(),
ysr@777 751 in_marking_window_im());
ysr@777 752 #endif // 0
ysr@777 753
ysr@777 754 if (_young_list_target_length < _young_list_min_length) {
ysr@777 755 // bummer; this means that, if we do a pause when the optimal
ysr@777 756 // config dictates, we'll violate the pause spacing target (the
ysr@777 757 // min length was calculate based on the application's current
ysr@777 758 // alloc rate);
ysr@777 759
ysr@777 760 // so, we have to bite the bullet, and allocate the minimum
ysr@777 761 // number. We'll violate our target, but we just can't meet it.
ysr@777 762
ysr@777 763 size_t so_length = 0;
ysr@777 764 // a note further up explains why we do not want an S-O length
ysr@777 765 // during marking
ysr@777 766 if (!_in_marking_window && !_last_full_young_gc)
ysr@777 767 // but we can still try to see whether we can find an optimal
ysr@777 768 // S-O length
ysr@777 769 so_length = calculate_optimal_so_length(_young_list_min_length);
ysr@777 770
ysr@777 771 #if 0
ysr@777 772 // leave this in for debugging, just in case
ysr@777 773 gclog_or_tty->print_cr("adjusted target length from "
ysr@777 774 SIZE_FORMAT " to " SIZE_FORMAT
ysr@777 775 ", SO " SIZE_FORMAT,
ysr@777 776 _young_list_target_length, _young_list_min_length,
ysr@777 777 so_length);
ysr@777 778 #endif // 0
ysr@777 779
ysr@777 780 _young_list_target_length =
ysr@777 781 MAX2(_young_list_min_length, (size_t)1);
ysr@777 782 _young_list_so_prefix_length = so_length;
ysr@777 783 }
ysr@777 784 } else {
ysr@777 785 // we are in a partially-young mode or we've run out of regions (due
ysr@777 786 // to evacuation failure)
ysr@777 787
ysr@777 788 #if 0
ysr@777 789 // leave this in for debugging, just in case
ysr@777 790 gclog_or_tty->print_cr("(partial) setting target to " SIZE_FORMAT
ysr@777 791 ", SO " SIZE_FORMAT,
ysr@777 792 _young_list_min_length, 0);
ysr@777 793 #endif // 0
ysr@777 794
ysr@777 795 // we'll do the pause as soon as possible and with no S-O prefix
ysr@777 796 // (see above for the reasons behind the latter)
ysr@777 797 _young_list_target_length =
ysr@777 798 MAX2(_young_list_min_length, (size_t) 1);
ysr@777 799 _young_list_so_prefix_length = 0;
ysr@777 800 }
ysr@777 801
ysr@777 802 _rs_lengths_prediction = rs_lengths;
ysr@777 803 }
ysr@777 804
ysr@777 805 // This is used by: calculate_optimal_so_length(length). It returns
ysr@777 806 // the GC eff and predicted pause time for a particular config
ysr@777 807 void
ysr@777 808 G1CollectorPolicy::predict_gc_eff(size_t young_length,
ysr@777 809 size_t so_length,
ysr@777 810 double base_time_ms,
ysr@777 811 double* ret_gc_eff,
ysr@777 812 double* ret_pause_time_ms) {
ysr@777 813 double so_time_ms = predict_scan_only_time_ms(so_length);
ysr@777 814 double accum_surv_rate_adj = 0.0;
ysr@777 815 if (so_length > 0)
ysr@777 816 accum_surv_rate_adj = accum_yg_surv_rate_pred((int)(so_length - 1));
ysr@777 817 double accum_surv_rate =
ysr@777 818 accum_yg_surv_rate_pred((int)(young_length - 1)) - accum_surv_rate_adj;
ysr@777 819 size_t bytes_to_copy =
ysr@777 820 (size_t) (accum_surv_rate * (double) HeapRegion::GrainBytes);
ysr@777 821 double copy_time_ms = predict_object_copy_time_ms(bytes_to_copy);
ysr@777 822 double young_other_time_ms =
ysr@777 823 predict_young_other_time_ms(young_length - so_length);
ysr@777 824 double pause_time_ms =
ysr@777 825 base_time_ms + so_time_ms + copy_time_ms + young_other_time_ms;
ysr@777 826 size_t reclaimed_bytes =
ysr@777 827 (young_length - so_length) * HeapRegion::GrainBytes - bytes_to_copy;
ysr@777 828 double gc_eff = (double) reclaimed_bytes / pause_time_ms;
ysr@777 829
ysr@777 830 *ret_gc_eff = gc_eff;
ysr@777 831 *ret_pause_time_ms = pause_time_ms;
ysr@777 832 }
ysr@777 833
ysr@777 834 // This is used by: calculate_young_list_target_config(rs_length). It
ysr@777 835 // returns the GC eff of a particular config. It returns false if that
ysr@777 836 // config violates any of the end conditions of the search in the
ysr@777 837 // calling method, or true upon success. The end conditions were put
ysr@777 838 // here since it's called twice and it was best not to replicate them
ysr@777 839 // in the caller. Also, passing the parameteres avoids having to
ysr@777 840 // recalculate them in the innermost loop.
ysr@777 841 bool
ysr@777 842 G1CollectorPolicy::predict_gc_eff(size_t young_length,
ysr@777 843 size_t so_length,
ysr@777 844 double base_time_with_so_ms,
ysr@777 845 size_t init_free_regions,
ysr@777 846 double target_pause_time_ms,
ysr@777 847 double* ret_gc_eff) {
ysr@777 848 *ret_gc_eff = 0.0;
ysr@777 849
ysr@777 850 if (young_length >= init_free_regions)
ysr@777 851 // end condition 1: not enough space for the young regions
ysr@777 852 return false;
ysr@777 853
ysr@777 854 double accum_surv_rate_adj = 0.0;
ysr@777 855 if (so_length > 0)
ysr@777 856 accum_surv_rate_adj = accum_yg_surv_rate_pred((int)(so_length - 1));
ysr@777 857 double accum_surv_rate =
ysr@777 858 accum_yg_surv_rate_pred((int)(young_length - 1)) - accum_surv_rate_adj;
ysr@777 859 size_t bytes_to_copy =
ysr@777 860 (size_t) (accum_surv_rate * (double) HeapRegion::GrainBytes);
ysr@777 861 double copy_time_ms = predict_object_copy_time_ms(bytes_to_copy);
ysr@777 862 double young_other_time_ms =
ysr@777 863 predict_young_other_time_ms(young_length - so_length);
ysr@777 864 double pause_time_ms =
ysr@777 865 base_time_with_so_ms + copy_time_ms + young_other_time_ms;
ysr@777 866
ysr@777 867 if (pause_time_ms > target_pause_time_ms)
ysr@777 868 // end condition 2: over the target pause time
ysr@777 869 return false;
ysr@777 870
ysr@777 871 size_t reclaimed_bytes =
ysr@777 872 (young_length - so_length) * HeapRegion::GrainBytes - bytes_to_copy;
ysr@777 873 size_t free_bytes =
ysr@777 874 (init_free_regions - young_length) * HeapRegion::GrainBytes;
ysr@777 875
ysr@777 876 if ((2.0 + sigma()) * (double) bytes_to_copy > (double) free_bytes)
ysr@777 877 // end condition 3: out of to-space (conservatively)
ysr@777 878 return false;
ysr@777 879
ysr@777 880 // success!
ysr@777 881 double gc_eff = (double) reclaimed_bytes / pause_time_ms;
ysr@777 882 *ret_gc_eff = gc_eff;
ysr@777 883
ysr@777 884 return true;
ysr@777 885 }
ysr@777 886
ysr@777 887 void G1CollectorPolicy::check_prediction_validity() {
ysr@777 888 guarantee( adaptive_young_list_length(), "should not call this otherwise" );
ysr@777 889
ysr@777 890 size_t rs_lengths = _g1->young_list_sampled_rs_lengths();
ysr@777 891 if (rs_lengths > _rs_lengths_prediction) {
ysr@777 892 // add 10% to avoid having to recalculate often
ysr@777 893 size_t rs_lengths_prediction = rs_lengths * 1100 / 1000;
ysr@777 894 calculate_young_list_target_config(rs_lengths_prediction);
ysr@777 895 }
ysr@777 896 }
ysr@777 897
ysr@777 898 HeapWord* G1CollectorPolicy::mem_allocate_work(size_t size,
ysr@777 899 bool is_tlab,
ysr@777 900 bool* gc_overhead_limit_was_exceeded) {
ysr@777 901 guarantee(false, "Not using this policy feature yet.");
ysr@777 902 return NULL;
ysr@777 903 }
ysr@777 904
ysr@777 905 // This method controls how a collector handles one or more
ysr@777 906 // of its generations being fully allocated.
ysr@777 907 HeapWord* G1CollectorPolicy::satisfy_failed_allocation(size_t size,
ysr@777 908 bool is_tlab) {
ysr@777 909 guarantee(false, "Not using this policy feature yet.");
ysr@777 910 return NULL;
ysr@777 911 }
ysr@777 912
ysr@777 913
ysr@777 914 #ifndef PRODUCT
ysr@777 915 bool G1CollectorPolicy::verify_young_ages() {
ysr@777 916 HeapRegion* head = _g1->young_list_first_region();
ysr@777 917 return
ysr@777 918 verify_young_ages(head, _short_lived_surv_rate_group);
ysr@777 919 // also call verify_young_ages on any additional surv rate groups
ysr@777 920 }
ysr@777 921
ysr@777 922 bool
ysr@777 923 G1CollectorPolicy::verify_young_ages(HeapRegion* head,
ysr@777 924 SurvRateGroup *surv_rate_group) {
ysr@777 925 guarantee( surv_rate_group != NULL, "pre-condition" );
ysr@777 926
ysr@777 927 const char* name = surv_rate_group->name();
ysr@777 928 bool ret = true;
ysr@777 929 int prev_age = -1;
ysr@777 930
ysr@777 931 for (HeapRegion* curr = head;
ysr@777 932 curr != NULL;
ysr@777 933 curr = curr->get_next_young_region()) {
ysr@777 934 SurvRateGroup* group = curr->surv_rate_group();
ysr@777 935 if (group == NULL && !curr->is_survivor()) {
ysr@777 936 gclog_or_tty->print_cr("## %s: encountered NULL surv_rate_group", name);
ysr@777 937 ret = false;
ysr@777 938 }
ysr@777 939
ysr@777 940 if (surv_rate_group == group) {
ysr@777 941 int age = curr->age_in_surv_rate_group();
ysr@777 942
ysr@777 943 if (age < 0) {
ysr@777 944 gclog_or_tty->print_cr("## %s: encountered negative age", name);
ysr@777 945 ret = false;
ysr@777 946 }
ysr@777 947
ysr@777 948 if (age <= prev_age) {
ysr@777 949 gclog_or_tty->print_cr("## %s: region ages are not strictly increasing "
ysr@777 950 "(%d, %d)", name, age, prev_age);
ysr@777 951 ret = false;
ysr@777 952 }
ysr@777 953 prev_age = age;
ysr@777 954 }
ysr@777 955 }
ysr@777 956
ysr@777 957 return ret;
ysr@777 958 }
ysr@777 959 #endif // PRODUCT
ysr@777 960
ysr@777 961 void G1CollectorPolicy::record_full_collection_start() {
ysr@777 962 _cur_collection_start_sec = os::elapsedTime();
ysr@777 963 // Release the future to-space so that it is available for compaction into.
ysr@777 964 _g1->set_full_collection();
ysr@777 965 }
ysr@777 966
ysr@777 967 void G1CollectorPolicy::record_full_collection_end() {
ysr@777 968 // Consider this like a collection pause for the purposes of allocation
ysr@777 969 // since last pause.
ysr@777 970 double end_sec = os::elapsedTime();
ysr@777 971 double full_gc_time_sec = end_sec - _cur_collection_start_sec;
ysr@777 972 double full_gc_time_ms = full_gc_time_sec * 1000.0;
ysr@777 973
ysr@777 974 checkpoint_conc_overhead();
ysr@777 975
ysr@777 976 _all_full_gc_times_ms->add(full_gc_time_ms);
ysr@777 977
ysr@777 978 update_recent_gc_times(end_sec, full_gc_time_sec);
ysr@777 979
ysr@777 980 _g1->clear_full_collection();
ysr@777 981
ysr@777 982 // "Nuke" the heuristics that control the fully/partially young GC
ysr@777 983 // transitions and make sure we start with fully young GCs after the
ysr@777 984 // Full GC.
ysr@777 985 set_full_young_gcs(true);
ysr@777 986 _last_full_young_gc = false;
ysr@777 987 _should_revert_to_full_young_gcs = false;
ysr@777 988 _should_initiate_conc_mark = false;
ysr@777 989 _known_garbage_bytes = 0;
ysr@777 990 _known_garbage_ratio = 0.0;
ysr@777 991 _in_marking_window = false;
ysr@777 992 _in_marking_window_im = false;
ysr@777 993
ysr@777 994 _short_lived_surv_rate_group->record_scan_only_prefix(0);
ysr@777 995 _short_lived_surv_rate_group->start_adding_regions();
ysr@777 996 // also call this on any additional surv rate groups
ysr@777 997
ysr@777 998 _prev_region_num_young = _region_num_young;
ysr@777 999 _prev_region_num_tenured = _region_num_tenured;
ysr@777 1000
ysr@777 1001 _free_regions_at_end_of_collection = _g1->free_regions();
ysr@777 1002 _scan_only_regions_at_end_of_collection = 0;
ysr@777 1003 calculate_young_list_min_length();
ysr@777 1004 calculate_young_list_target_config();
ysr@777 1005 }
ysr@777 1006
ysr@777 1007 void G1CollectorPolicy::record_pop_compute_rc_start() {
ysr@777 1008 _pop_compute_rc_start = os::elapsedTime();
ysr@777 1009 }
ysr@777 1010 void G1CollectorPolicy::record_pop_compute_rc_end() {
ysr@777 1011 double ms = (os::elapsedTime() - _pop_compute_rc_start)*1000.0;
ysr@777 1012 _cur_popular_compute_rc_time_ms = ms;
ysr@777 1013 _pop_compute_rc_start = 0.0;
ysr@777 1014 }
ysr@777 1015 void G1CollectorPolicy::record_pop_evac_start() {
ysr@777 1016 _pop_evac_start = os::elapsedTime();
ysr@777 1017 }
ysr@777 1018 void G1CollectorPolicy::record_pop_evac_end() {
ysr@777 1019 double ms = (os::elapsedTime() - _pop_evac_start)*1000.0;
ysr@777 1020 _cur_popular_evac_time_ms = ms;
ysr@777 1021 _pop_evac_start = 0.0;
ysr@777 1022 }
ysr@777 1023
ysr@777 1024 void G1CollectorPolicy::record_before_bytes(size_t bytes) {
ysr@777 1025 _bytes_in_to_space_before_gc += bytes;
ysr@777 1026 }
ysr@777 1027
ysr@777 1028 void G1CollectorPolicy::record_after_bytes(size_t bytes) {
ysr@777 1029 _bytes_in_to_space_after_gc += bytes;
ysr@777 1030 }
ysr@777 1031
ysr@777 1032 void G1CollectorPolicy::record_stop_world_start() {
ysr@777 1033 _stop_world_start = os::elapsedTime();
ysr@777 1034 }
ysr@777 1035
ysr@777 1036 void G1CollectorPolicy::record_collection_pause_start(double start_time_sec,
ysr@777 1037 size_t start_used) {
ysr@777 1038 if (PrintGCDetails) {
ysr@777 1039 gclog_or_tty->stamp(PrintGCTimeStamps);
ysr@777 1040 gclog_or_tty->print("[GC pause");
ysr@777 1041 if (in_young_gc_mode())
ysr@777 1042 gclog_or_tty->print(" (%s)", full_young_gcs() ? "young" : "partial");
ysr@777 1043 }
ysr@777 1044
ysr@777 1045 assert(_g1->used_regions() == _g1->recalculate_used_regions(),
ysr@777 1046 "sanity");
ysr@777 1047
ysr@777 1048 double s_w_t_ms = (start_time_sec - _stop_world_start) * 1000.0;
ysr@777 1049 _all_stop_world_times_ms->add(s_w_t_ms);
ysr@777 1050 _stop_world_start = 0.0;
ysr@777 1051
ysr@777 1052 _cur_collection_start_sec = start_time_sec;
ysr@777 1053 _cur_collection_pause_used_at_start_bytes = start_used;
ysr@777 1054 _cur_collection_pause_used_regions_at_start = _g1->used_regions();
ysr@777 1055 _pending_cards = _g1->pending_card_num();
ysr@777 1056 _max_pending_cards = _g1->max_pending_card_num();
ysr@777 1057
ysr@777 1058 _bytes_in_to_space_before_gc = 0;
ysr@777 1059 _bytes_in_to_space_after_gc = 0;
ysr@777 1060 _bytes_in_collection_set_before_gc = 0;
ysr@777 1061
ysr@777 1062 #ifdef DEBUG
ysr@777 1063 // initialise these to something well known so that we can spot
ysr@777 1064 // if they are not set properly
ysr@777 1065
ysr@777 1066 for (int i = 0; i < _parallel_gc_threads; ++i) {
ysr@777 1067 _par_last_ext_root_scan_times_ms[i] = -666.0;
ysr@777 1068 _par_last_mark_stack_scan_times_ms[i] = -666.0;
ysr@777 1069 _par_last_scan_only_times_ms[i] = -666.0;
ysr@777 1070 _par_last_scan_only_regions_scanned[i] = -666.0;
ysr@777 1071 _par_last_update_rs_start_times_ms[i] = -666.0;
ysr@777 1072 _par_last_update_rs_times_ms[i] = -666.0;
ysr@777 1073 _par_last_update_rs_processed_buffers[i] = -666.0;
ysr@777 1074 _par_last_scan_rs_start_times_ms[i] = -666.0;
ysr@777 1075 _par_last_scan_rs_times_ms[i] = -666.0;
ysr@777 1076 _par_last_scan_new_refs_times_ms[i] = -666.0;
ysr@777 1077 _par_last_obj_copy_times_ms[i] = -666.0;
ysr@777 1078 _par_last_termination_times_ms[i] = -666.0;
ysr@777 1079
ysr@777 1080 _pop_par_last_update_rs_start_times_ms[i] = -666.0;
ysr@777 1081 _pop_par_last_update_rs_times_ms[i] = -666.0;
ysr@777 1082 _pop_par_last_update_rs_processed_buffers[i] = -666.0;
ysr@777 1083 _pop_par_last_scan_rs_start_times_ms[i] = -666.0;
ysr@777 1084 _pop_par_last_scan_rs_times_ms[i] = -666.0;
ysr@777 1085 _pop_par_last_closure_app_times_ms[i] = -666.0;
ysr@777 1086 }
ysr@777 1087 #endif
ysr@777 1088
ysr@777 1089 for (int i = 0; i < _aux_num; ++i) {
ysr@777 1090 _cur_aux_times_ms[i] = 0.0;
ysr@777 1091 _cur_aux_times_set[i] = false;
ysr@777 1092 }
ysr@777 1093
ysr@777 1094 _satb_drain_time_set = false;
ysr@777 1095 _last_satb_drain_processed_buffers = -1;
ysr@777 1096
ysr@777 1097 if (in_young_gc_mode())
ysr@777 1098 _last_young_gc_full = false;
ysr@777 1099
ysr@777 1100
ysr@777 1101 // do that for any other surv rate groups
ysr@777 1102 _short_lived_surv_rate_group->stop_adding_regions();
ysr@777 1103 size_t short_lived_so_length = _young_list_so_prefix_length;
ysr@777 1104 _short_lived_surv_rate_group->record_scan_only_prefix(short_lived_so_length);
ysr@777 1105 tag_scan_only(short_lived_so_length);
ysr@777 1106
ysr@777 1107 assert( verify_young_ages(), "region age verification" );
ysr@777 1108 }
ysr@777 1109
ysr@777 1110 void G1CollectorPolicy::tag_scan_only(size_t short_lived_scan_only_length) {
ysr@777 1111 // done in a way that it can be extended for other surv rate groups too...
ysr@777 1112
ysr@777 1113 HeapRegion* head = _g1->young_list_first_region();
ysr@777 1114 bool finished_short_lived = (short_lived_scan_only_length == 0);
ysr@777 1115
ysr@777 1116 if (finished_short_lived)
ysr@777 1117 return;
ysr@777 1118
ysr@777 1119 for (HeapRegion* curr = head;
ysr@777 1120 curr != NULL;
ysr@777 1121 curr = curr->get_next_young_region()) {
ysr@777 1122 SurvRateGroup* surv_rate_group = curr->surv_rate_group();
ysr@777 1123 int age = curr->age_in_surv_rate_group();
ysr@777 1124
ysr@777 1125 if (surv_rate_group == _short_lived_surv_rate_group) {
ysr@777 1126 if ((size_t)age < short_lived_scan_only_length)
ysr@777 1127 curr->set_scan_only();
ysr@777 1128 else
ysr@777 1129 finished_short_lived = true;
ysr@777 1130 }
ysr@777 1131
ysr@777 1132
ysr@777 1133 if (finished_short_lived)
ysr@777 1134 return;
ysr@777 1135 }
ysr@777 1136
ysr@777 1137 guarantee( false, "we should never reach here" );
ysr@777 1138 }
ysr@777 1139
ysr@777 1140 void G1CollectorPolicy::record_popular_pause_preamble_start() {
ysr@777 1141 _cur_popular_preamble_start_ms = os::elapsedTime() * 1000.0;
ysr@777 1142 }
ysr@777 1143
ysr@777 1144 void G1CollectorPolicy::record_popular_pause_preamble_end() {
ysr@777 1145 _cur_popular_preamble_time_ms =
ysr@777 1146 (os::elapsedTime() * 1000.0) - _cur_popular_preamble_start_ms;
ysr@777 1147
ysr@777 1148 // copy the recorded statistics of the first pass to temporary arrays
ysr@777 1149 for (int i = 0; i < _parallel_gc_threads; ++i) {
ysr@777 1150 _pop_par_last_update_rs_start_times_ms[i] = _par_last_update_rs_start_times_ms[i];
ysr@777 1151 _pop_par_last_update_rs_times_ms[i] = _par_last_update_rs_times_ms[i];
ysr@777 1152 _pop_par_last_update_rs_processed_buffers[i] = _par_last_update_rs_processed_buffers[i];
ysr@777 1153 _pop_par_last_scan_rs_start_times_ms[i] = _par_last_scan_rs_start_times_ms[i];
ysr@777 1154 _pop_par_last_scan_rs_times_ms[i] = _par_last_scan_rs_times_ms[i];
ysr@777 1155 _pop_par_last_closure_app_times_ms[i] = _par_last_obj_copy_times_ms[i];
ysr@777 1156 }
ysr@777 1157 }
ysr@777 1158
ysr@777 1159 void G1CollectorPolicy::record_mark_closure_time(double mark_closure_time_ms) {
ysr@777 1160 _mark_closure_time_ms = mark_closure_time_ms;
ysr@777 1161 }
ysr@777 1162
ysr@777 1163 void G1CollectorPolicy::record_concurrent_mark_init_start() {
ysr@777 1164 _mark_init_start_sec = os::elapsedTime();
ysr@777 1165 guarantee(!in_young_gc_mode(), "should not do be here in young GC mode");
ysr@777 1166 }
ysr@777 1167
ysr@777 1168 void G1CollectorPolicy::record_concurrent_mark_init_end_pre(double
ysr@777 1169 mark_init_elapsed_time_ms) {
ysr@777 1170 _during_marking = true;
ysr@777 1171 _should_initiate_conc_mark = false;
ysr@777 1172 _cur_mark_stop_world_time_ms = mark_init_elapsed_time_ms;
ysr@777 1173 }
ysr@777 1174
ysr@777 1175 void G1CollectorPolicy::record_concurrent_mark_init_end() {
ysr@777 1176 double end_time_sec = os::elapsedTime();
ysr@777 1177 double elapsed_time_ms = (end_time_sec - _mark_init_start_sec) * 1000.0;
ysr@777 1178 _concurrent_mark_init_times_ms->add(elapsed_time_ms);
ysr@777 1179 checkpoint_conc_overhead();
ysr@777 1180 record_concurrent_mark_init_end_pre(elapsed_time_ms);
ysr@777 1181
ysr@777 1182 _mmu_tracker->add_pause(_mark_init_start_sec, end_time_sec, true);
ysr@777 1183 }
ysr@777 1184
ysr@777 1185 void G1CollectorPolicy::record_concurrent_mark_remark_start() {
ysr@777 1186 _mark_remark_start_sec = os::elapsedTime();
ysr@777 1187 _during_marking = false;
ysr@777 1188 }
ysr@777 1189
ysr@777 1190 void G1CollectorPolicy::record_concurrent_mark_remark_end() {
ysr@777 1191 double end_time_sec = os::elapsedTime();
ysr@777 1192 double elapsed_time_ms = (end_time_sec - _mark_remark_start_sec)*1000.0;
ysr@777 1193 checkpoint_conc_overhead();
ysr@777 1194 _concurrent_mark_remark_times_ms->add(elapsed_time_ms);
ysr@777 1195 _cur_mark_stop_world_time_ms += elapsed_time_ms;
ysr@777 1196 _prev_collection_pause_end_ms += elapsed_time_ms;
ysr@777 1197
ysr@777 1198 _mmu_tracker->add_pause(_mark_remark_start_sec, end_time_sec, true);
ysr@777 1199 }
ysr@777 1200
ysr@777 1201 void G1CollectorPolicy::record_concurrent_mark_cleanup_start() {
ysr@777 1202 _mark_cleanup_start_sec = os::elapsedTime();
ysr@777 1203 }
ysr@777 1204
ysr@777 1205 void
ysr@777 1206 G1CollectorPolicy::record_concurrent_mark_cleanup_end(size_t freed_bytes,
ysr@777 1207 size_t max_live_bytes) {
ysr@777 1208 record_concurrent_mark_cleanup_end_work1(freed_bytes, max_live_bytes);
ysr@777 1209 record_concurrent_mark_cleanup_end_work2();
ysr@777 1210 }
ysr@777 1211
ysr@777 1212 void
ysr@777 1213 G1CollectorPolicy::
ysr@777 1214 record_concurrent_mark_cleanup_end_work1(size_t freed_bytes,
ysr@777 1215 size_t max_live_bytes) {
ysr@777 1216 if (_n_marks < 2) _n_marks++;
ysr@777 1217 if (G1PolicyVerbose > 0)
ysr@777 1218 gclog_or_tty->print_cr("At end of marking, max_live is " SIZE_FORMAT " MB "
ysr@777 1219 " (of " SIZE_FORMAT " MB heap).",
ysr@777 1220 max_live_bytes/M, _g1->capacity()/M);
ysr@777 1221 }
ysr@777 1222
ysr@777 1223 // The important thing about this is that it includes "os::elapsedTime".
ysr@777 1224 void G1CollectorPolicy::record_concurrent_mark_cleanup_end_work2() {
ysr@777 1225 checkpoint_conc_overhead();
ysr@777 1226 double end_time_sec = os::elapsedTime();
ysr@777 1227 double elapsed_time_ms = (end_time_sec - _mark_cleanup_start_sec)*1000.0;
ysr@777 1228 _concurrent_mark_cleanup_times_ms->add(elapsed_time_ms);
ysr@777 1229 _cur_mark_stop_world_time_ms += elapsed_time_ms;
ysr@777 1230 _prev_collection_pause_end_ms += elapsed_time_ms;
ysr@777 1231
ysr@777 1232 _mmu_tracker->add_pause(_mark_cleanup_start_sec, end_time_sec, true);
ysr@777 1233
ysr@777 1234 _num_markings++;
ysr@777 1235
ysr@777 1236 // We did a marking, so reset the "since_last_mark" variables.
ysr@777 1237 double considerConcMarkCost = 1.0;
ysr@777 1238 // If there are available processors, concurrent activity is free...
ysr@777 1239 if (Threads::number_of_non_daemon_threads() * 2 <
ysr@777 1240 os::active_processor_count()) {
ysr@777 1241 considerConcMarkCost = 0.0;
ysr@777 1242 }
ysr@777 1243 _n_pauses_at_mark_end = _n_pauses;
ysr@777 1244 _n_marks_since_last_pause++;
ysr@777 1245 _conc_mark_initiated = false;
ysr@777 1246 }
ysr@777 1247
ysr@777 1248 void
ysr@777 1249 G1CollectorPolicy::record_concurrent_mark_cleanup_completed() {
ysr@777 1250 if (in_young_gc_mode()) {
ysr@777 1251 _should_revert_to_full_young_gcs = false;
ysr@777 1252 _last_full_young_gc = true;
ysr@777 1253 _in_marking_window = false;
ysr@777 1254 if (adaptive_young_list_length())
ysr@777 1255 calculate_young_list_target_config();
ysr@777 1256 }
ysr@777 1257 }
ysr@777 1258
ysr@777 1259 void G1CollectorPolicy::record_concurrent_pause() {
ysr@777 1260 if (_stop_world_start > 0.0) {
ysr@777 1261 double yield_ms = (os::elapsedTime() - _stop_world_start) * 1000.0;
ysr@777 1262 _all_yield_times_ms->add(yield_ms);
ysr@777 1263 }
ysr@777 1264 }
ysr@777 1265
ysr@777 1266 void G1CollectorPolicy::record_concurrent_pause_end() {
ysr@777 1267 }
ysr@777 1268
ysr@777 1269 void G1CollectorPolicy::record_collection_pause_end_CH_strong_roots() {
ysr@777 1270 _cur_CH_strong_roots_end_sec = os::elapsedTime();
ysr@777 1271 _cur_CH_strong_roots_dur_ms =
ysr@777 1272 (_cur_CH_strong_roots_end_sec - _cur_collection_start_sec) * 1000.0;
ysr@777 1273 }
ysr@777 1274
ysr@777 1275 void G1CollectorPolicy::record_collection_pause_end_G1_strong_roots() {
ysr@777 1276 _cur_G1_strong_roots_end_sec = os::elapsedTime();
ysr@777 1277 _cur_G1_strong_roots_dur_ms =
ysr@777 1278 (_cur_G1_strong_roots_end_sec - _cur_CH_strong_roots_end_sec) * 1000.0;
ysr@777 1279 }
ysr@777 1280
ysr@777 1281 template<class T>
ysr@777 1282 T sum_of(T* sum_arr, int start, int n, int N) {
ysr@777 1283 T sum = (T)0;
ysr@777 1284 for (int i = 0; i < n; i++) {
ysr@777 1285 int j = (start + i) % N;
ysr@777 1286 sum += sum_arr[j];
ysr@777 1287 }
ysr@777 1288 return sum;
ysr@777 1289 }
ysr@777 1290
ysr@777 1291 void G1CollectorPolicy::print_par_stats (int level,
ysr@777 1292 const char* str,
ysr@777 1293 double* data,
ysr@777 1294 bool summary) {
ysr@777 1295 double min = data[0], max = data[0];
ysr@777 1296 double total = 0.0;
ysr@777 1297 int j;
ysr@777 1298 for (j = 0; j < level; ++j)
ysr@777 1299 gclog_or_tty->print(" ");
ysr@777 1300 gclog_or_tty->print("[%s (ms):", str);
ysr@777 1301 for (uint i = 0; i < ParallelGCThreads; ++i) {
ysr@777 1302 double val = data[i];
ysr@777 1303 if (val < min)
ysr@777 1304 min = val;
ysr@777 1305 if (val > max)
ysr@777 1306 max = val;
ysr@777 1307 total += val;
ysr@777 1308 gclog_or_tty->print(" %3.1lf", val);
ysr@777 1309 }
ysr@777 1310 if (summary) {
ysr@777 1311 gclog_or_tty->print_cr("");
ysr@777 1312 double avg = total / (double) ParallelGCThreads;
ysr@777 1313 gclog_or_tty->print(" ");
ysr@777 1314 for (j = 0; j < level; ++j)
ysr@777 1315 gclog_or_tty->print(" ");
ysr@777 1316 gclog_or_tty->print("Avg: %5.1lf, Min: %5.1lf, Max: %5.1lf",
ysr@777 1317 avg, min, max);
ysr@777 1318 }
ysr@777 1319 gclog_or_tty->print_cr("]");
ysr@777 1320 }
ysr@777 1321
ysr@777 1322 void G1CollectorPolicy::print_par_buffers (int level,
ysr@777 1323 const char* str,
ysr@777 1324 double* data,
ysr@777 1325 bool summary) {
ysr@777 1326 double min = data[0], max = data[0];
ysr@777 1327 double total = 0.0;
ysr@777 1328 int j;
ysr@777 1329 for (j = 0; j < level; ++j)
ysr@777 1330 gclog_or_tty->print(" ");
ysr@777 1331 gclog_or_tty->print("[%s :", str);
ysr@777 1332 for (uint i = 0; i < ParallelGCThreads; ++i) {
ysr@777 1333 double val = data[i];
ysr@777 1334 if (val < min)
ysr@777 1335 min = val;
ysr@777 1336 if (val > max)
ysr@777 1337 max = val;
ysr@777 1338 total += val;
ysr@777 1339 gclog_or_tty->print(" %d", (int) val);
ysr@777 1340 }
ysr@777 1341 if (summary) {
ysr@777 1342 gclog_or_tty->print_cr("");
ysr@777 1343 double avg = total / (double) ParallelGCThreads;
ysr@777 1344 gclog_or_tty->print(" ");
ysr@777 1345 for (j = 0; j < level; ++j)
ysr@777 1346 gclog_or_tty->print(" ");
ysr@777 1347 gclog_or_tty->print("Sum: %d, Avg: %d, Min: %d, Max: %d",
ysr@777 1348 (int)total, (int)avg, (int)min, (int)max);
ysr@777 1349 }
ysr@777 1350 gclog_or_tty->print_cr("]");
ysr@777 1351 }
ysr@777 1352
ysr@777 1353 void G1CollectorPolicy::print_stats (int level,
ysr@777 1354 const char* str,
ysr@777 1355 double value) {
ysr@777 1356 for (int j = 0; j < level; ++j)
ysr@777 1357 gclog_or_tty->print(" ");
ysr@777 1358 gclog_or_tty->print_cr("[%s: %5.1lf ms]", str, value);
ysr@777 1359 }
ysr@777 1360
ysr@777 1361 void G1CollectorPolicy::print_stats (int level,
ysr@777 1362 const char* str,
ysr@777 1363 int value) {
ysr@777 1364 for (int j = 0; j < level; ++j)
ysr@777 1365 gclog_or_tty->print(" ");
ysr@777 1366 gclog_or_tty->print_cr("[%s: %d]", str, value);
ysr@777 1367 }
ysr@777 1368
ysr@777 1369 double G1CollectorPolicy::avg_value (double* data) {
ysr@777 1370 if (ParallelGCThreads > 0) {
ysr@777 1371 double ret = 0.0;
ysr@777 1372 for (uint i = 0; i < ParallelGCThreads; ++i)
ysr@777 1373 ret += data[i];
ysr@777 1374 return ret / (double) ParallelGCThreads;
ysr@777 1375 } else {
ysr@777 1376 return data[0];
ysr@777 1377 }
ysr@777 1378 }
ysr@777 1379
ysr@777 1380 double G1CollectorPolicy::max_value (double* data) {
ysr@777 1381 if (ParallelGCThreads > 0) {
ysr@777 1382 double ret = data[0];
ysr@777 1383 for (uint i = 1; i < ParallelGCThreads; ++i)
ysr@777 1384 if (data[i] > ret)
ysr@777 1385 ret = data[i];
ysr@777 1386 return ret;
ysr@777 1387 } else {
ysr@777 1388 return data[0];
ysr@777 1389 }
ysr@777 1390 }
ysr@777 1391
ysr@777 1392 double G1CollectorPolicy::sum_of_values (double* data) {
ysr@777 1393 if (ParallelGCThreads > 0) {
ysr@777 1394 double sum = 0.0;
ysr@777 1395 for (uint i = 0; i < ParallelGCThreads; i++)
ysr@777 1396 sum += data[i];
ysr@777 1397 return sum;
ysr@777 1398 } else {
ysr@777 1399 return data[0];
ysr@777 1400 }
ysr@777 1401 }
ysr@777 1402
ysr@777 1403 double G1CollectorPolicy::max_sum (double* data1,
ysr@777 1404 double* data2) {
ysr@777 1405 double ret = data1[0] + data2[0];
ysr@777 1406
ysr@777 1407 if (ParallelGCThreads > 0) {
ysr@777 1408 for (uint i = 1; i < ParallelGCThreads; ++i) {
ysr@777 1409 double data = data1[i] + data2[i];
ysr@777 1410 if (data > ret)
ysr@777 1411 ret = data;
ysr@777 1412 }
ysr@777 1413 }
ysr@777 1414 return ret;
ysr@777 1415 }
ysr@777 1416
ysr@777 1417 // Anything below that is considered to be zero
ysr@777 1418 #define MIN_TIMER_GRANULARITY 0.0000001
ysr@777 1419
ysr@777 1420 void G1CollectorPolicy::record_collection_pause_end(bool popular,
ysr@777 1421 bool abandoned) {
ysr@777 1422 double end_time_sec = os::elapsedTime();
ysr@777 1423 double elapsed_ms = _last_pause_time_ms;
ysr@777 1424 bool parallel = ParallelGCThreads > 0;
ysr@777 1425 double evac_ms = (end_time_sec - _cur_G1_strong_roots_end_sec) * 1000.0;
ysr@777 1426 size_t rs_size =
ysr@777 1427 _cur_collection_pause_used_regions_at_start - collection_set_size();
ysr@777 1428 size_t cur_used_bytes = _g1->used();
ysr@777 1429 assert(cur_used_bytes == _g1->recalculate_used(), "It should!");
ysr@777 1430 bool last_pause_included_initial_mark = false;
ysr@777 1431
ysr@777 1432 #ifndef PRODUCT
ysr@777 1433 if (G1YoungSurvRateVerbose) {
ysr@777 1434 gclog_or_tty->print_cr("");
ysr@777 1435 _short_lived_surv_rate_group->print();
ysr@777 1436 // do that for any other surv rate groups too
ysr@777 1437 }
ysr@777 1438 #endif // PRODUCT
ysr@777 1439
ysr@777 1440 checkpoint_conc_overhead();
ysr@777 1441
ysr@777 1442 if (in_young_gc_mode()) {
ysr@777 1443 last_pause_included_initial_mark = _should_initiate_conc_mark;
ysr@777 1444 if (last_pause_included_initial_mark)
ysr@777 1445 record_concurrent_mark_init_end_pre(0.0);
ysr@777 1446
ysr@777 1447 size_t min_used_targ =
ysr@777 1448 (_g1->capacity() / 100) * (G1SteadyStateUsed - G1SteadyStateUsedDelta);
ysr@777 1449
ysr@777 1450 if (cur_used_bytes > min_used_targ) {
ysr@777 1451 if (cur_used_bytes <= _prev_collection_pause_used_at_end_bytes) {
ysr@777 1452 } else if (!_g1->mark_in_progress() && !_last_full_young_gc) {
ysr@777 1453 _should_initiate_conc_mark = true;
ysr@777 1454 }
ysr@777 1455 }
ysr@777 1456
ysr@777 1457 _prev_collection_pause_used_at_end_bytes = cur_used_bytes;
ysr@777 1458 }
ysr@777 1459
ysr@777 1460 _mmu_tracker->add_pause(end_time_sec - elapsed_ms/1000.0,
ysr@777 1461 end_time_sec, false);
ysr@777 1462
ysr@777 1463 guarantee(_cur_collection_pause_used_regions_at_start >=
ysr@777 1464 collection_set_size(),
ysr@777 1465 "Negative RS size?");
ysr@777 1466
ysr@777 1467 // This assert is exempted when we're doing parallel collection pauses,
ysr@777 1468 // because the fragmentation caused by the parallel GC allocation buffers
ysr@777 1469 // can lead to more memory being used during collection than was used
ysr@777 1470 // before. Best leave this out until the fragmentation problem is fixed.
ysr@777 1471 // Pauses in which evacuation failed can also lead to negative
ysr@777 1472 // collections, since no space is reclaimed from a region containing an
ysr@777 1473 // object whose evacuation failed.
ysr@777 1474 // Further, we're now always doing parallel collection. But I'm still
ysr@777 1475 // leaving this here as a placeholder for a more precise assertion later.
ysr@777 1476 // (DLD, 10/05.)
ysr@777 1477 assert((true || parallel) // Always using GC LABs now.
ysr@777 1478 || _g1->evacuation_failed()
ysr@777 1479 || _cur_collection_pause_used_at_start_bytes >= cur_used_bytes,
ysr@777 1480 "Negative collection");
ysr@777 1481
ysr@777 1482 size_t freed_bytes =
ysr@777 1483 _cur_collection_pause_used_at_start_bytes - cur_used_bytes;
ysr@777 1484 size_t surviving_bytes = _collection_set_bytes_used_before - freed_bytes;
ysr@777 1485 double survival_fraction =
ysr@777 1486 (double)surviving_bytes/
ysr@777 1487 (double)_collection_set_bytes_used_before;
ysr@777 1488
ysr@777 1489 _n_pauses++;
ysr@777 1490
ysr@777 1491 if (!abandoned) {
ysr@777 1492 _recent_CH_strong_roots_times_ms->add(_cur_CH_strong_roots_dur_ms);
ysr@777 1493 _recent_G1_strong_roots_times_ms->add(_cur_G1_strong_roots_dur_ms);
ysr@777 1494 _recent_evac_times_ms->add(evac_ms);
ysr@777 1495 _recent_pause_times_ms->add(elapsed_ms);
ysr@777 1496
ysr@777 1497 _recent_rs_sizes->add(rs_size);
ysr@777 1498
ysr@777 1499 // We exempt parallel collection from this check because Alloc Buffer
ysr@777 1500 // fragmentation can produce negative collections. Same with evac
ysr@777 1501 // failure.
ysr@777 1502 // Further, we're now always doing parallel collection. But I'm still
ysr@777 1503 // leaving this here as a placeholder for a more precise assertion later.
ysr@777 1504 // (DLD, 10/05.
ysr@777 1505 assert((true || parallel)
ysr@777 1506 || _g1->evacuation_failed()
ysr@777 1507 || surviving_bytes <= _collection_set_bytes_used_before,
ysr@777 1508 "Or else negative collection!");
ysr@777 1509 _recent_CS_bytes_used_before->add(_collection_set_bytes_used_before);
ysr@777 1510 _recent_CS_bytes_surviving->add(surviving_bytes);
ysr@777 1511
ysr@777 1512 // this is where we update the allocation rate of the application
ysr@777 1513 double app_time_ms =
ysr@777 1514 (_cur_collection_start_sec * 1000.0 - _prev_collection_pause_end_ms);
ysr@777 1515 if (app_time_ms < MIN_TIMER_GRANULARITY) {
ysr@777 1516 // This usually happens due to the timer not having the required
ysr@777 1517 // granularity. Some Linuxes are the usual culprits.
ysr@777 1518 // We'll just set it to something (arbitrarily) small.
ysr@777 1519 app_time_ms = 1.0;
ysr@777 1520 }
ysr@777 1521 size_t regions_allocated =
ysr@777 1522 (_region_num_young - _prev_region_num_young) +
ysr@777 1523 (_region_num_tenured - _prev_region_num_tenured);
ysr@777 1524 double alloc_rate_ms = (double) regions_allocated / app_time_ms;
ysr@777 1525 _alloc_rate_ms_seq->add(alloc_rate_ms);
ysr@777 1526 _prev_region_num_young = _region_num_young;
ysr@777 1527 _prev_region_num_tenured = _region_num_tenured;
ysr@777 1528
ysr@777 1529 double interval_ms =
ysr@777 1530 (end_time_sec - _recent_prev_end_times_for_all_gcs_sec->oldest()) * 1000.0;
ysr@777 1531 update_recent_gc_times(end_time_sec, elapsed_ms);
ysr@777 1532 _recent_avg_pause_time_ratio = _recent_gc_times_ms->sum()/interval_ms;
ysr@777 1533 assert(recent_avg_pause_time_ratio() < 1.00, "All GC?");
ysr@777 1534 }
ysr@777 1535
ysr@777 1536 if (G1PolicyVerbose > 1) {
ysr@777 1537 gclog_or_tty->print_cr(" Recording collection pause(%d)", _n_pauses);
ysr@777 1538 }
ysr@777 1539
ysr@777 1540 PauseSummary* summary;
ysr@777 1541 if (!abandoned && !popular)
ysr@777 1542 summary = _non_pop_summary;
ysr@777 1543 else if (!abandoned && popular)
ysr@777 1544 summary = _pop_summary;
ysr@777 1545 else if (abandoned && !popular)
ysr@777 1546 summary = _non_pop_abandoned_summary;
ysr@777 1547 else if (abandoned && popular)
ysr@777 1548 summary = _pop_abandoned_summary;
ysr@777 1549 else
ysr@777 1550 guarantee(false, "should not get here!");
ysr@777 1551
ysr@777 1552 double pop_update_rs_time;
ysr@777 1553 double pop_update_rs_processed_buffers;
ysr@777 1554 double pop_scan_rs_time;
ysr@777 1555 double pop_closure_app_time;
ysr@777 1556 double pop_other_time;
ysr@777 1557
ysr@777 1558 if (popular) {
ysr@777 1559 PopPreambleSummary* preamble_summary = summary->pop_preamble_summary();
ysr@777 1560 guarantee(preamble_summary != NULL, "should not be null!");
ysr@777 1561
ysr@777 1562 pop_update_rs_time = avg_value(_pop_par_last_update_rs_times_ms);
ysr@777 1563 pop_update_rs_processed_buffers =
ysr@777 1564 sum_of_values(_pop_par_last_update_rs_processed_buffers);
ysr@777 1565 pop_scan_rs_time = avg_value(_pop_par_last_scan_rs_times_ms);
ysr@777 1566 pop_closure_app_time = avg_value(_pop_par_last_closure_app_times_ms);
ysr@777 1567 pop_other_time = _cur_popular_preamble_time_ms -
ysr@777 1568 (pop_update_rs_time + pop_scan_rs_time + pop_closure_app_time +
ysr@777 1569 _cur_popular_evac_time_ms);
ysr@777 1570
ysr@777 1571 preamble_summary->record_pop_preamble_time_ms(_cur_popular_preamble_time_ms);
ysr@777 1572 preamble_summary->record_pop_update_rs_time_ms(pop_update_rs_time);
ysr@777 1573 preamble_summary->record_pop_scan_rs_time_ms(pop_scan_rs_time);
ysr@777 1574 preamble_summary->record_pop_closure_app_time_ms(pop_closure_app_time);
ysr@777 1575 preamble_summary->record_pop_evacuation_time_ms(_cur_popular_evac_time_ms);
ysr@777 1576 preamble_summary->record_pop_other_time_ms(pop_other_time);
ysr@777 1577 }
ysr@777 1578
ysr@777 1579 double ext_root_scan_time = avg_value(_par_last_ext_root_scan_times_ms);
ysr@777 1580 double mark_stack_scan_time = avg_value(_par_last_mark_stack_scan_times_ms);
ysr@777 1581 double scan_only_time = avg_value(_par_last_scan_only_times_ms);
ysr@777 1582 double scan_only_regions_scanned =
ysr@777 1583 sum_of_values(_par_last_scan_only_regions_scanned);
ysr@777 1584 double update_rs_time = avg_value(_par_last_update_rs_times_ms);
ysr@777 1585 double update_rs_processed_buffers =
ysr@777 1586 sum_of_values(_par_last_update_rs_processed_buffers);
ysr@777 1587 double scan_rs_time = avg_value(_par_last_scan_rs_times_ms);
ysr@777 1588 double obj_copy_time = avg_value(_par_last_obj_copy_times_ms);
ysr@777 1589 double termination_time = avg_value(_par_last_termination_times_ms);
ysr@777 1590
ysr@777 1591 double parallel_other_time;
ysr@777 1592 if (!abandoned) {
ysr@777 1593 MainBodySummary* body_summary = summary->main_body_summary();
ysr@777 1594 guarantee(body_summary != NULL, "should not be null!");
ysr@777 1595
ysr@777 1596 if (_satb_drain_time_set)
ysr@777 1597 body_summary->record_satb_drain_time_ms(_cur_satb_drain_time_ms);
ysr@777 1598 else
ysr@777 1599 body_summary->record_satb_drain_time_ms(0.0);
ysr@777 1600 body_summary->record_ext_root_scan_time_ms(ext_root_scan_time);
ysr@777 1601 body_summary->record_mark_stack_scan_time_ms(mark_stack_scan_time);
ysr@777 1602 body_summary->record_scan_only_time_ms(scan_only_time);
ysr@777 1603 body_summary->record_update_rs_time_ms(update_rs_time);
ysr@777 1604 body_summary->record_scan_rs_time_ms(scan_rs_time);
ysr@777 1605 body_summary->record_obj_copy_time_ms(obj_copy_time);
ysr@777 1606 if (parallel) {
ysr@777 1607 body_summary->record_parallel_time_ms(_cur_collection_par_time_ms);
ysr@777 1608 body_summary->record_clear_ct_time_ms(_cur_clear_ct_time_ms);
ysr@777 1609 body_summary->record_termination_time_ms(termination_time);
ysr@777 1610 parallel_other_time = _cur_collection_par_time_ms -
ysr@777 1611 (update_rs_time + ext_root_scan_time + mark_stack_scan_time +
ysr@777 1612 scan_only_time + scan_rs_time + obj_copy_time + termination_time);
ysr@777 1613 body_summary->record_parallel_other_time_ms(parallel_other_time);
ysr@777 1614 }
ysr@777 1615 body_summary->record_mark_closure_time_ms(_mark_closure_time_ms);
ysr@777 1616 }
ysr@777 1617
ysr@777 1618 if (G1PolicyVerbose > 1) {
ysr@777 1619 gclog_or_tty->print_cr(" ET: %10.6f ms (avg: %10.6f ms)\n"
ysr@777 1620 " CH Strong: %10.6f ms (avg: %10.6f ms)\n"
ysr@777 1621 " G1 Strong: %10.6f ms (avg: %10.6f ms)\n"
ysr@777 1622 " Evac: %10.6f ms (avg: %10.6f ms)\n"
ysr@777 1623 " ET-RS: %10.6f ms (avg: %10.6f ms)\n"
ysr@777 1624 " |RS|: " SIZE_FORMAT,
ysr@777 1625 elapsed_ms, recent_avg_time_for_pauses_ms(),
ysr@777 1626 _cur_CH_strong_roots_dur_ms, recent_avg_time_for_CH_strong_ms(),
ysr@777 1627 _cur_G1_strong_roots_dur_ms, recent_avg_time_for_G1_strong_ms(),
ysr@777 1628 evac_ms, recent_avg_time_for_evac_ms(),
ysr@777 1629 scan_rs_time,
ysr@777 1630 recent_avg_time_for_pauses_ms() -
ysr@777 1631 recent_avg_time_for_G1_strong_ms(),
ysr@777 1632 rs_size);
ysr@777 1633
ysr@777 1634 gclog_or_tty->print_cr(" Used at start: " SIZE_FORMAT"K"
ysr@777 1635 " At end " SIZE_FORMAT "K\n"
ysr@777 1636 " garbage : " SIZE_FORMAT "K"
ysr@777 1637 " of " SIZE_FORMAT "K\n"
ysr@777 1638 " survival : %6.2f%% (%6.2f%% avg)",
ysr@777 1639 _cur_collection_pause_used_at_start_bytes/K,
ysr@777 1640 _g1->used()/K, freed_bytes/K,
ysr@777 1641 _collection_set_bytes_used_before/K,
ysr@777 1642 survival_fraction*100.0,
ysr@777 1643 recent_avg_survival_fraction()*100.0);
ysr@777 1644 gclog_or_tty->print_cr(" Recent %% gc pause time: %6.2f",
ysr@777 1645 recent_avg_pause_time_ratio() * 100.0);
ysr@777 1646 }
ysr@777 1647
ysr@777 1648 double other_time_ms = elapsed_ms;
ysr@777 1649 if (popular)
ysr@777 1650 other_time_ms -= _cur_popular_preamble_time_ms;
ysr@777 1651
ysr@777 1652 if (!abandoned) {
ysr@777 1653 if (_satb_drain_time_set)
ysr@777 1654 other_time_ms -= _cur_satb_drain_time_ms;
ysr@777 1655
ysr@777 1656 if (parallel)
ysr@777 1657 other_time_ms -= _cur_collection_par_time_ms + _cur_clear_ct_time_ms;
ysr@777 1658 else
ysr@777 1659 other_time_ms -=
ysr@777 1660 update_rs_time +
ysr@777 1661 ext_root_scan_time + mark_stack_scan_time + scan_only_time +
ysr@777 1662 scan_rs_time + obj_copy_time;
ysr@777 1663 }
ysr@777 1664
ysr@777 1665 if (PrintGCDetails) {
ysr@777 1666 gclog_or_tty->print_cr("%s%s, %1.8lf secs]",
ysr@777 1667 (popular && !abandoned) ? " (popular)" :
ysr@777 1668 (!popular && abandoned) ? " (abandoned)" :
ysr@777 1669 (popular && abandoned) ? " (popular/abandoned)" : "",
ysr@777 1670 (last_pause_included_initial_mark) ? " (initial-mark)" : "",
ysr@777 1671 elapsed_ms / 1000.0);
ysr@777 1672
ysr@777 1673 if (!abandoned) {
ysr@777 1674 if (_satb_drain_time_set)
ysr@777 1675 print_stats(1, "SATB Drain Time", _cur_satb_drain_time_ms);
ysr@777 1676 if (_last_satb_drain_processed_buffers >= 0)
ysr@777 1677 print_stats(2, "Processed Buffers", _last_satb_drain_processed_buffers);
ysr@777 1678 }
ysr@777 1679 if (popular)
ysr@777 1680 print_stats(1, "Popularity Preamble", _cur_popular_preamble_time_ms);
ysr@777 1681 if (parallel) {
ysr@777 1682 if (popular) {
ysr@777 1683 print_par_stats(2, "Update RS (Start)", _pop_par_last_update_rs_start_times_ms, false);
ysr@777 1684 print_par_stats(2, "Update RS", _pop_par_last_update_rs_times_ms);
ysr@777 1685 if (G1RSBarrierUseQueue)
ysr@777 1686 print_par_buffers(3, "Processed Buffers",
ysr@777 1687 _pop_par_last_update_rs_processed_buffers, true);
ysr@777 1688 print_par_stats(2, "Scan RS", _pop_par_last_scan_rs_times_ms);
ysr@777 1689 print_par_stats(2, "Closure app", _pop_par_last_closure_app_times_ms);
ysr@777 1690 print_stats(2, "Evacuation", _cur_popular_evac_time_ms);
ysr@777 1691 print_stats(2, "Other", pop_other_time);
ysr@777 1692 }
ysr@777 1693 if (!abandoned) {
ysr@777 1694 print_stats(1, "Parallel Time", _cur_collection_par_time_ms);
ysr@777 1695 if (!popular) {
ysr@777 1696 print_par_stats(2, "Update RS (Start)", _par_last_update_rs_start_times_ms, false);
ysr@777 1697 print_par_stats(2, "Update RS", _par_last_update_rs_times_ms);
ysr@777 1698 if (G1RSBarrierUseQueue)
ysr@777 1699 print_par_buffers(3, "Processed Buffers",
ysr@777 1700 _par_last_update_rs_processed_buffers, true);
ysr@777 1701 }
ysr@777 1702 print_par_stats(2, "Ext Root Scanning", _par_last_ext_root_scan_times_ms);
ysr@777 1703 print_par_stats(2, "Mark Stack Scanning", _par_last_mark_stack_scan_times_ms);
ysr@777 1704 print_par_stats(2, "Scan-Only Scanning", _par_last_scan_only_times_ms);
ysr@777 1705 print_par_buffers(3, "Scan-Only Regions",
ysr@777 1706 _par_last_scan_only_regions_scanned, true);
ysr@777 1707 print_par_stats(2, "Scan RS", _par_last_scan_rs_times_ms);
ysr@777 1708 print_par_stats(2, "Object Copy", _par_last_obj_copy_times_ms);
ysr@777 1709 print_par_stats(2, "Termination", _par_last_termination_times_ms);
ysr@777 1710 print_stats(2, "Other", parallel_other_time);
ysr@777 1711 print_stats(1, "Clear CT", _cur_clear_ct_time_ms);
ysr@777 1712 }
ysr@777 1713 } else {
ysr@777 1714 if (popular) {
ysr@777 1715 print_stats(2, "Update RS", pop_update_rs_time);
ysr@777 1716 if (G1RSBarrierUseQueue)
ysr@777 1717 print_stats(3, "Processed Buffers",
ysr@777 1718 (int)pop_update_rs_processed_buffers);
ysr@777 1719 print_stats(2, "Scan RS", pop_scan_rs_time);
ysr@777 1720 print_stats(2, "Closure App", pop_closure_app_time);
ysr@777 1721 print_stats(2, "Evacuation", _cur_popular_evac_time_ms);
ysr@777 1722 print_stats(2, "Other", pop_other_time);
ysr@777 1723 }
ysr@777 1724 if (!abandoned) {
ysr@777 1725 if (!popular) {
ysr@777 1726 print_stats(1, "Update RS", update_rs_time);
ysr@777 1727 if (G1RSBarrierUseQueue)
ysr@777 1728 print_stats(2, "Processed Buffers",
ysr@777 1729 (int)update_rs_processed_buffers);
ysr@777 1730 }
ysr@777 1731 print_stats(1, "Ext Root Scanning", ext_root_scan_time);
ysr@777 1732 print_stats(1, "Mark Stack Scanning", mark_stack_scan_time);
ysr@777 1733 print_stats(1, "Scan-Only Scanning", scan_only_time);
ysr@777 1734 print_stats(1, "Scan RS", scan_rs_time);
ysr@777 1735 print_stats(1, "Object Copying", obj_copy_time);
ysr@777 1736 }
ysr@777 1737 }
ysr@777 1738 print_stats(1, "Other", other_time_ms);
ysr@777 1739 for (int i = 0; i < _aux_num; ++i) {
ysr@777 1740 if (_cur_aux_times_set[i]) {
ysr@777 1741 char buffer[96];
ysr@777 1742 sprintf(buffer, "Aux%d", i);
ysr@777 1743 print_stats(1, buffer, _cur_aux_times_ms[i]);
ysr@777 1744 }
ysr@777 1745 }
ysr@777 1746 }
ysr@777 1747 if (PrintGCDetails)
ysr@777 1748 gclog_or_tty->print(" [");
ysr@777 1749 if (PrintGC || PrintGCDetails)
ysr@777 1750 _g1->print_size_transition(gclog_or_tty,
ysr@777 1751 _cur_collection_pause_used_at_start_bytes,
ysr@777 1752 _g1->used(), _g1->capacity());
ysr@777 1753 if (PrintGCDetails)
ysr@777 1754 gclog_or_tty->print_cr("]");
ysr@777 1755
ysr@777 1756 _all_pause_times_ms->add(elapsed_ms);
ysr@777 1757 summary->record_total_time_ms(elapsed_ms);
ysr@777 1758 summary->record_other_time_ms(other_time_ms);
ysr@777 1759 for (int i = 0; i < _aux_num; ++i)
ysr@777 1760 if (_cur_aux_times_set[i])
ysr@777 1761 _all_aux_times_ms[i].add(_cur_aux_times_ms[i]);
ysr@777 1762
ysr@777 1763 // Reset marks-between-pauses counter.
ysr@777 1764 _n_marks_since_last_pause = 0;
ysr@777 1765
ysr@777 1766 // Update the efficiency-since-mark vars.
ysr@777 1767 double proc_ms = elapsed_ms * (double) _parallel_gc_threads;
ysr@777 1768 if (elapsed_ms < MIN_TIMER_GRANULARITY) {
ysr@777 1769 // This usually happens due to the timer not having the required
ysr@777 1770 // granularity. Some Linuxes are the usual culprits.
ysr@777 1771 // We'll just set it to something (arbitrarily) small.
ysr@777 1772 proc_ms = 1.0;
ysr@777 1773 }
ysr@777 1774 double cur_efficiency = (double) freed_bytes / proc_ms;
ysr@777 1775
ysr@777 1776 bool new_in_marking_window = _in_marking_window;
ysr@777 1777 bool new_in_marking_window_im = false;
ysr@777 1778 if (_should_initiate_conc_mark) {
ysr@777 1779 new_in_marking_window = true;
ysr@777 1780 new_in_marking_window_im = true;
ysr@777 1781 }
ysr@777 1782
ysr@777 1783 if (in_young_gc_mode()) {
ysr@777 1784 if (_last_full_young_gc) {
ysr@777 1785 set_full_young_gcs(false);
ysr@777 1786 _last_full_young_gc = false;
ysr@777 1787 }
ysr@777 1788
ysr@777 1789 if ( !_last_young_gc_full ) {
ysr@777 1790 if ( _should_revert_to_full_young_gcs ||
ysr@777 1791 _known_garbage_ratio < 0.05 ||
ysr@777 1792 (adaptive_young_list_length() &&
ysr@777 1793 (get_gc_eff_factor() * cur_efficiency < predict_young_gc_eff())) ) {
ysr@777 1794 set_full_young_gcs(true);
ysr@777 1795 }
ysr@777 1796 }
ysr@777 1797 _should_revert_to_full_young_gcs = false;
ysr@777 1798
ysr@777 1799 if (_last_young_gc_full && !_during_marking)
ysr@777 1800 _young_gc_eff_seq->add(cur_efficiency);
ysr@777 1801 }
ysr@777 1802
ysr@777 1803 _short_lived_surv_rate_group->start_adding_regions();
ysr@777 1804 // do that for any other surv rate groupsx
ysr@777 1805
ysr@777 1806 // <NEW PREDICTION>
ysr@777 1807
ysr@777 1808 if (!popular && !abandoned) {
ysr@777 1809 double pause_time_ms = elapsed_ms;
ysr@777 1810
ysr@777 1811 size_t diff = 0;
ysr@777 1812 if (_max_pending_cards >= _pending_cards)
ysr@777 1813 diff = _max_pending_cards - _pending_cards;
ysr@777 1814 _pending_card_diff_seq->add((double) diff);
ysr@777 1815
ysr@777 1816 double cost_per_card_ms = 0.0;
ysr@777 1817 if (_pending_cards > 0) {
ysr@777 1818 cost_per_card_ms = update_rs_time / (double) _pending_cards;
ysr@777 1819 _cost_per_card_ms_seq->add(cost_per_card_ms);
ysr@777 1820 }
ysr@777 1821
ysr@777 1822 double cost_per_scan_only_region_ms = 0.0;
ysr@777 1823 if (scan_only_regions_scanned > 0.0) {
ysr@777 1824 cost_per_scan_only_region_ms =
ysr@777 1825 scan_only_time / scan_only_regions_scanned;
ysr@777 1826 if (_in_marking_window_im)
ysr@777 1827 _cost_per_scan_only_region_ms_during_cm_seq->add(cost_per_scan_only_region_ms);
ysr@777 1828 else
ysr@777 1829 _cost_per_scan_only_region_ms_seq->add(cost_per_scan_only_region_ms);
ysr@777 1830 }
ysr@777 1831
ysr@777 1832 size_t cards_scanned = _g1->cards_scanned();
ysr@777 1833
ysr@777 1834 double cost_per_entry_ms = 0.0;
ysr@777 1835 if (cards_scanned > 10) {
ysr@777 1836 cost_per_entry_ms = scan_rs_time / (double) cards_scanned;
ysr@777 1837 if (_last_young_gc_full)
ysr@777 1838 _cost_per_entry_ms_seq->add(cost_per_entry_ms);
ysr@777 1839 else
ysr@777 1840 _partially_young_cost_per_entry_ms_seq->add(cost_per_entry_ms);
ysr@777 1841 }
ysr@777 1842
ysr@777 1843 if (_max_rs_lengths > 0) {
ysr@777 1844 double cards_per_entry_ratio =
ysr@777 1845 (double) cards_scanned / (double) _max_rs_lengths;
ysr@777 1846 if (_last_young_gc_full)
ysr@777 1847 _fully_young_cards_per_entry_ratio_seq->add(cards_per_entry_ratio);
ysr@777 1848 else
ysr@777 1849 _partially_young_cards_per_entry_ratio_seq->add(cards_per_entry_ratio);
ysr@777 1850 }
ysr@777 1851
ysr@777 1852 size_t rs_length_diff = _max_rs_lengths - _recorded_rs_lengths;
ysr@777 1853 if (rs_length_diff >= 0)
ysr@777 1854 _rs_length_diff_seq->add((double) rs_length_diff);
ysr@777 1855
ysr@777 1856 size_t copied_bytes = surviving_bytes;
ysr@777 1857 double cost_per_byte_ms = 0.0;
ysr@777 1858 if (copied_bytes > 0) {
ysr@777 1859 cost_per_byte_ms = obj_copy_time / (double) copied_bytes;
ysr@777 1860 if (_in_marking_window)
ysr@777 1861 _cost_per_byte_ms_during_cm_seq->add(cost_per_byte_ms);
ysr@777 1862 else
ysr@777 1863 _cost_per_byte_ms_seq->add(cost_per_byte_ms);
ysr@777 1864 }
ysr@777 1865
ysr@777 1866 double all_other_time_ms = pause_time_ms -
ysr@777 1867 (update_rs_time + scan_only_time + scan_rs_time + obj_copy_time +
ysr@777 1868 _mark_closure_time_ms + termination_time);
ysr@777 1869
ysr@777 1870 double young_other_time_ms = 0.0;
ysr@777 1871 if (_recorded_young_regions > 0) {
ysr@777 1872 young_other_time_ms =
ysr@777 1873 _recorded_young_cset_choice_time_ms +
ysr@777 1874 _recorded_young_free_cset_time_ms;
ysr@777 1875 _young_other_cost_per_region_ms_seq->add(young_other_time_ms /
ysr@777 1876 (double) _recorded_young_regions);
ysr@777 1877 }
ysr@777 1878 double non_young_other_time_ms = 0.0;
ysr@777 1879 if (_recorded_non_young_regions > 0) {
ysr@777 1880 non_young_other_time_ms =
ysr@777 1881 _recorded_non_young_cset_choice_time_ms +
ysr@777 1882 _recorded_non_young_free_cset_time_ms;
ysr@777 1883
ysr@777 1884 _non_young_other_cost_per_region_ms_seq->add(non_young_other_time_ms /
ysr@777 1885 (double) _recorded_non_young_regions);
ysr@777 1886 }
ysr@777 1887
ysr@777 1888 double constant_other_time_ms = all_other_time_ms -
ysr@777 1889 (young_other_time_ms + non_young_other_time_ms);
ysr@777 1890 _constant_other_time_ms_seq->add(constant_other_time_ms);
ysr@777 1891
ysr@777 1892 double survival_ratio = 0.0;
ysr@777 1893 if (_bytes_in_collection_set_before_gc > 0) {
ysr@777 1894 survival_ratio = (double) bytes_in_to_space_during_gc() /
ysr@777 1895 (double) _bytes_in_collection_set_before_gc;
ysr@777 1896 }
ysr@777 1897
ysr@777 1898 _pending_cards_seq->add((double) _pending_cards);
ysr@777 1899 _scanned_cards_seq->add((double) cards_scanned);
ysr@777 1900 _rs_lengths_seq->add((double) _max_rs_lengths);
ysr@777 1901
ysr@777 1902 double expensive_region_limit_ms =
ysr@777 1903 (double) G1MaxPauseTimeMS - predict_constant_other_time_ms();
ysr@777 1904 if (expensive_region_limit_ms < 0.0) {
ysr@777 1905 // this means that the other time was predicted to be longer than
ysr@777 1906 // than the max pause time
ysr@777 1907 expensive_region_limit_ms = (double) G1MaxPauseTimeMS;
ysr@777 1908 }
ysr@777 1909 _expensive_region_limit_ms = expensive_region_limit_ms;
ysr@777 1910
ysr@777 1911 if (PREDICTIONS_VERBOSE) {
ysr@777 1912 gclog_or_tty->print_cr("");
ysr@777 1913 gclog_or_tty->print_cr("PREDICTIONS %1.4lf %d "
ysr@777 1914 "REGIONS %d %d %d %d "
ysr@777 1915 "PENDING_CARDS %d %d "
ysr@777 1916 "CARDS_SCANNED %d %d "
ysr@777 1917 "RS_LENGTHS %d %d "
ysr@777 1918 "SCAN_ONLY_SCAN %1.6lf %1.6lf "
ysr@777 1919 "RS_UPDATE %1.6lf %1.6lf RS_SCAN %1.6lf %1.6lf "
ysr@777 1920 "SURVIVAL_RATIO %1.6lf %1.6lf "
ysr@777 1921 "OBJECT_COPY %1.6lf %1.6lf OTHER_CONSTANT %1.6lf %1.6lf "
ysr@777 1922 "OTHER_YOUNG %1.6lf %1.6lf "
ysr@777 1923 "OTHER_NON_YOUNG %1.6lf %1.6lf "
ysr@777 1924 "VTIME_DIFF %1.6lf TERMINATION %1.6lf "
ysr@777 1925 "ELAPSED %1.6lf %1.6lf ",
ysr@777 1926 _cur_collection_start_sec,
ysr@777 1927 (!_last_young_gc_full) ? 2 :
ysr@777 1928 (last_pause_included_initial_mark) ? 1 : 0,
ysr@777 1929 _recorded_region_num,
ysr@777 1930 _recorded_young_regions,
ysr@777 1931 _recorded_scan_only_regions,
ysr@777 1932 _recorded_non_young_regions,
ysr@777 1933 _predicted_pending_cards, _pending_cards,
ysr@777 1934 _predicted_cards_scanned, cards_scanned,
ysr@777 1935 _predicted_rs_lengths, _max_rs_lengths,
ysr@777 1936 _predicted_scan_only_scan_time_ms, scan_only_time,
ysr@777 1937 _predicted_rs_update_time_ms, update_rs_time,
ysr@777 1938 _predicted_rs_scan_time_ms, scan_rs_time,
ysr@777 1939 _predicted_survival_ratio, survival_ratio,
ysr@777 1940 _predicted_object_copy_time_ms, obj_copy_time,
ysr@777 1941 _predicted_constant_other_time_ms, constant_other_time_ms,
ysr@777 1942 _predicted_young_other_time_ms, young_other_time_ms,
ysr@777 1943 _predicted_non_young_other_time_ms,
ysr@777 1944 non_young_other_time_ms,
ysr@777 1945 _vtime_diff_ms, termination_time,
ysr@777 1946 _predicted_pause_time_ms, elapsed_ms);
ysr@777 1947 }
ysr@777 1948
ysr@777 1949 if (G1PolicyVerbose > 0) {
ysr@777 1950 gclog_or_tty->print_cr("Pause Time, predicted: %1.4lfms (predicted %s), actual: %1.4lfms",
ysr@777 1951 _predicted_pause_time_ms,
ysr@777 1952 (_within_target) ? "within" : "outside",
ysr@777 1953 elapsed_ms);
ysr@777 1954 }
ysr@777 1955
ysr@777 1956 }
ysr@777 1957
ysr@777 1958 _in_marking_window = new_in_marking_window;
ysr@777 1959 _in_marking_window_im = new_in_marking_window_im;
ysr@777 1960 _free_regions_at_end_of_collection = _g1->free_regions();
ysr@777 1961 _scan_only_regions_at_end_of_collection = _g1->young_list_length();
ysr@777 1962 calculate_young_list_min_length();
ysr@777 1963 calculate_young_list_target_config();
ysr@777 1964
ysr@777 1965 // </NEW PREDICTION>
ysr@777 1966
ysr@777 1967 _target_pause_time_ms = -1.0;
ysr@777 1968
ysr@777 1969 // TODO: calculate tenuring threshold
ysr@777 1970 _tenuring_threshold = MaxTenuringThreshold;
ysr@777 1971 }
ysr@777 1972
ysr@777 1973 // <NEW PREDICTION>
ysr@777 1974
ysr@777 1975 double
ysr@777 1976 G1CollectorPolicy::
ysr@777 1977 predict_young_collection_elapsed_time_ms(size_t adjustment) {
ysr@777 1978 guarantee( adjustment == 0 || adjustment == 1, "invariant" );
ysr@777 1979
ysr@777 1980 G1CollectedHeap* g1h = G1CollectedHeap::heap();
ysr@777 1981 size_t young_num = g1h->young_list_length();
ysr@777 1982 if (young_num == 0)
ysr@777 1983 return 0.0;
ysr@777 1984
ysr@777 1985 young_num += adjustment;
ysr@777 1986 size_t pending_cards = predict_pending_cards();
ysr@777 1987 size_t rs_lengths = g1h->young_list_sampled_rs_lengths() +
ysr@777 1988 predict_rs_length_diff();
ysr@777 1989 size_t card_num;
ysr@777 1990 if (full_young_gcs())
ysr@777 1991 card_num = predict_young_card_num(rs_lengths);
ysr@777 1992 else
ysr@777 1993 card_num = predict_non_young_card_num(rs_lengths);
ysr@777 1994 size_t young_byte_size = young_num * HeapRegion::GrainBytes;
ysr@777 1995 double accum_yg_surv_rate =
ysr@777 1996 _short_lived_surv_rate_group->accum_surv_rate(adjustment);
ysr@777 1997
ysr@777 1998 size_t bytes_to_copy =
ysr@777 1999 (size_t) (accum_yg_surv_rate * (double) HeapRegion::GrainBytes);
ysr@777 2000
ysr@777 2001 return
ysr@777 2002 predict_rs_update_time_ms(pending_cards) +
ysr@777 2003 predict_rs_scan_time_ms(card_num) +
ysr@777 2004 predict_object_copy_time_ms(bytes_to_copy) +
ysr@777 2005 predict_young_other_time_ms(young_num) +
ysr@777 2006 predict_constant_other_time_ms();
ysr@777 2007 }
ysr@777 2008
ysr@777 2009 double
ysr@777 2010 G1CollectorPolicy::predict_base_elapsed_time_ms(size_t pending_cards) {
ysr@777 2011 size_t rs_length = predict_rs_length_diff();
ysr@777 2012 size_t card_num;
ysr@777 2013 if (full_young_gcs())
ysr@777 2014 card_num = predict_young_card_num(rs_length);
ysr@777 2015 else
ysr@777 2016 card_num = predict_non_young_card_num(rs_length);
ysr@777 2017 return predict_base_elapsed_time_ms(pending_cards, card_num);
ysr@777 2018 }
ysr@777 2019
ysr@777 2020 double
ysr@777 2021 G1CollectorPolicy::predict_base_elapsed_time_ms(size_t pending_cards,
ysr@777 2022 size_t scanned_cards) {
ysr@777 2023 return
ysr@777 2024 predict_rs_update_time_ms(pending_cards) +
ysr@777 2025 predict_rs_scan_time_ms(scanned_cards) +
ysr@777 2026 predict_constant_other_time_ms();
ysr@777 2027 }
ysr@777 2028
ysr@777 2029 double
ysr@777 2030 G1CollectorPolicy::predict_region_elapsed_time_ms(HeapRegion* hr,
ysr@777 2031 bool young) {
ysr@777 2032 size_t rs_length = hr->rem_set()->occupied();
ysr@777 2033 size_t card_num;
ysr@777 2034 if (full_young_gcs())
ysr@777 2035 card_num = predict_young_card_num(rs_length);
ysr@777 2036 else
ysr@777 2037 card_num = predict_non_young_card_num(rs_length);
ysr@777 2038 size_t bytes_to_copy = predict_bytes_to_copy(hr);
ysr@777 2039
ysr@777 2040 double region_elapsed_time_ms =
ysr@777 2041 predict_rs_scan_time_ms(card_num) +
ysr@777 2042 predict_object_copy_time_ms(bytes_to_copy);
ysr@777 2043
ysr@777 2044 if (young)
ysr@777 2045 region_elapsed_time_ms += predict_young_other_time_ms(1);
ysr@777 2046 else
ysr@777 2047 region_elapsed_time_ms += predict_non_young_other_time_ms(1);
ysr@777 2048
ysr@777 2049 return region_elapsed_time_ms;
ysr@777 2050 }
ysr@777 2051
ysr@777 2052 size_t
ysr@777 2053 G1CollectorPolicy::predict_bytes_to_copy(HeapRegion* hr) {
ysr@777 2054 size_t bytes_to_copy;
ysr@777 2055 if (hr->is_marked())
ysr@777 2056 bytes_to_copy = hr->max_live_bytes();
ysr@777 2057 else {
ysr@777 2058 guarantee( hr->is_young() && hr->age_in_surv_rate_group() != -1,
ysr@777 2059 "invariant" );
ysr@777 2060 int age = hr->age_in_surv_rate_group();
ysr@777 2061 double yg_surv_rate = predict_yg_surv_rate(age);
ysr@777 2062 bytes_to_copy = (size_t) ((double) hr->used() * yg_surv_rate);
ysr@777 2063 }
ysr@777 2064
ysr@777 2065 return bytes_to_copy;
ysr@777 2066 }
ysr@777 2067
ysr@777 2068 void
ysr@777 2069 G1CollectorPolicy::start_recording_regions() {
ysr@777 2070 _recorded_rs_lengths = 0;
ysr@777 2071 _recorded_scan_only_regions = 0;
ysr@777 2072 _recorded_young_regions = 0;
ysr@777 2073 _recorded_non_young_regions = 0;
ysr@777 2074
ysr@777 2075 #if PREDICTIONS_VERBOSE
ysr@777 2076 _predicted_rs_lengths = 0;
ysr@777 2077 _predicted_cards_scanned = 0;
ysr@777 2078
ysr@777 2079 _recorded_marked_bytes = 0;
ysr@777 2080 _recorded_young_bytes = 0;
ysr@777 2081 _predicted_bytes_to_copy = 0;
ysr@777 2082 #endif // PREDICTIONS_VERBOSE
ysr@777 2083 }
ysr@777 2084
ysr@777 2085 void
ysr@777 2086 G1CollectorPolicy::record_cset_region(HeapRegion* hr, bool young) {
ysr@777 2087 if (young) {
ysr@777 2088 ++_recorded_young_regions;
ysr@777 2089 } else {
ysr@777 2090 ++_recorded_non_young_regions;
ysr@777 2091 }
ysr@777 2092 #if PREDICTIONS_VERBOSE
ysr@777 2093 if (young) {
ysr@777 2094 _recorded_young_bytes += hr->asSpace()->used();
ysr@777 2095 } else {
ysr@777 2096 _recorded_marked_bytes += hr->max_live_bytes();
ysr@777 2097 }
ysr@777 2098 _predicted_bytes_to_copy += predict_bytes_to_copy(hr);
ysr@777 2099 #endif // PREDICTIONS_VERBOSE
ysr@777 2100
ysr@777 2101 size_t rs_length = hr->rem_set()->occupied();
ysr@777 2102 _recorded_rs_lengths += rs_length;
ysr@777 2103 }
ysr@777 2104
ysr@777 2105 void
ysr@777 2106 G1CollectorPolicy::record_scan_only_regions(size_t scan_only_length) {
ysr@777 2107 _recorded_scan_only_regions = scan_only_length;
ysr@777 2108 }
ysr@777 2109
ysr@777 2110 void
ysr@777 2111 G1CollectorPolicy::end_recording_regions() {
ysr@777 2112 #if PREDICTIONS_VERBOSE
ysr@777 2113 _predicted_pending_cards = predict_pending_cards();
ysr@777 2114 _predicted_rs_lengths = _recorded_rs_lengths + predict_rs_length_diff();
ysr@777 2115 if (full_young_gcs())
ysr@777 2116 _predicted_cards_scanned += predict_young_card_num(_predicted_rs_lengths);
ysr@777 2117 else
ysr@777 2118 _predicted_cards_scanned +=
ysr@777 2119 predict_non_young_card_num(_predicted_rs_lengths);
ysr@777 2120 _recorded_region_num = _recorded_young_regions + _recorded_non_young_regions;
ysr@777 2121
ysr@777 2122 _predicted_young_survival_ratio = 0.0;
ysr@777 2123 for (int i = 0; i < _recorded_young_regions; ++i)
ysr@777 2124 _predicted_young_survival_ratio += predict_yg_surv_rate(i);
ysr@777 2125 _predicted_young_survival_ratio /= (double) _recorded_young_regions;
ysr@777 2126
ysr@777 2127 _predicted_scan_only_scan_time_ms =
ysr@777 2128 predict_scan_only_time_ms(_recorded_scan_only_regions);
ysr@777 2129 _predicted_rs_update_time_ms =
ysr@777 2130 predict_rs_update_time_ms(_g1->pending_card_num());
ysr@777 2131 _predicted_rs_scan_time_ms =
ysr@777 2132 predict_rs_scan_time_ms(_predicted_cards_scanned);
ysr@777 2133 _predicted_object_copy_time_ms =
ysr@777 2134 predict_object_copy_time_ms(_predicted_bytes_to_copy);
ysr@777 2135 _predicted_constant_other_time_ms =
ysr@777 2136 predict_constant_other_time_ms();
ysr@777 2137 _predicted_young_other_time_ms =
ysr@777 2138 predict_young_other_time_ms(_recorded_young_regions);
ysr@777 2139 _predicted_non_young_other_time_ms =
ysr@777 2140 predict_non_young_other_time_ms(_recorded_non_young_regions);
ysr@777 2141
ysr@777 2142 _predicted_pause_time_ms =
ysr@777 2143 _predicted_scan_only_scan_time_ms +
ysr@777 2144 _predicted_rs_update_time_ms +
ysr@777 2145 _predicted_rs_scan_time_ms +
ysr@777 2146 _predicted_object_copy_time_ms +
ysr@777 2147 _predicted_constant_other_time_ms +
ysr@777 2148 _predicted_young_other_time_ms +
ysr@777 2149 _predicted_non_young_other_time_ms;
ysr@777 2150 #endif // PREDICTIONS_VERBOSE
ysr@777 2151 }
ysr@777 2152
ysr@777 2153 void G1CollectorPolicy::check_if_region_is_too_expensive(double
ysr@777 2154 predicted_time_ms) {
ysr@777 2155 // I don't think we need to do this when in young GC mode since
ysr@777 2156 // marking will be initiated next time we hit the soft limit anyway...
ysr@777 2157 if (predicted_time_ms > _expensive_region_limit_ms) {
ysr@777 2158 if (!in_young_gc_mode()) {
ysr@777 2159 set_full_young_gcs(true);
ysr@777 2160 _should_initiate_conc_mark = true;
ysr@777 2161 } else
ysr@777 2162 // no point in doing another partial one
ysr@777 2163 _should_revert_to_full_young_gcs = true;
ysr@777 2164 }
ysr@777 2165 }
ysr@777 2166
ysr@777 2167 // </NEW PREDICTION>
ysr@777 2168
ysr@777 2169
ysr@777 2170 void G1CollectorPolicy::update_recent_gc_times(double end_time_sec,
ysr@777 2171 double elapsed_ms) {
ysr@777 2172 _recent_gc_times_ms->add(elapsed_ms);
ysr@777 2173 _recent_prev_end_times_for_all_gcs_sec->add(end_time_sec);
ysr@777 2174 _prev_collection_pause_end_ms = end_time_sec * 1000.0;
ysr@777 2175 }
ysr@777 2176
ysr@777 2177 double G1CollectorPolicy::recent_avg_time_for_pauses_ms() {
ysr@777 2178 if (_recent_pause_times_ms->num() == 0) return (double) G1MaxPauseTimeMS;
ysr@777 2179 else return _recent_pause_times_ms->avg();
ysr@777 2180 }
ysr@777 2181
ysr@777 2182 double G1CollectorPolicy::recent_avg_time_for_CH_strong_ms() {
ysr@777 2183 if (_recent_CH_strong_roots_times_ms->num() == 0)
ysr@777 2184 return (double)G1MaxPauseTimeMS/3.0;
ysr@777 2185 else return _recent_CH_strong_roots_times_ms->avg();
ysr@777 2186 }
ysr@777 2187
ysr@777 2188 double G1CollectorPolicy::recent_avg_time_for_G1_strong_ms() {
ysr@777 2189 if (_recent_G1_strong_roots_times_ms->num() == 0)
ysr@777 2190 return (double)G1MaxPauseTimeMS/3.0;
ysr@777 2191 else return _recent_G1_strong_roots_times_ms->avg();
ysr@777 2192 }
ysr@777 2193
ysr@777 2194 double G1CollectorPolicy::recent_avg_time_for_evac_ms() {
ysr@777 2195 if (_recent_evac_times_ms->num() == 0) return (double)G1MaxPauseTimeMS/3.0;
ysr@777 2196 else return _recent_evac_times_ms->avg();
ysr@777 2197 }
ysr@777 2198
ysr@777 2199 int G1CollectorPolicy::number_of_recent_gcs() {
ysr@777 2200 assert(_recent_CH_strong_roots_times_ms->num() ==
ysr@777 2201 _recent_G1_strong_roots_times_ms->num(), "Sequence out of sync");
ysr@777 2202 assert(_recent_G1_strong_roots_times_ms->num() ==
ysr@777 2203 _recent_evac_times_ms->num(), "Sequence out of sync");
ysr@777 2204 assert(_recent_evac_times_ms->num() ==
ysr@777 2205 _recent_pause_times_ms->num(), "Sequence out of sync");
ysr@777 2206 assert(_recent_pause_times_ms->num() ==
ysr@777 2207 _recent_CS_bytes_used_before->num(), "Sequence out of sync");
ysr@777 2208 assert(_recent_CS_bytes_used_before->num() ==
ysr@777 2209 _recent_CS_bytes_surviving->num(), "Sequence out of sync");
ysr@777 2210 return _recent_pause_times_ms->num();
ysr@777 2211 }
ysr@777 2212
ysr@777 2213 double G1CollectorPolicy::recent_avg_survival_fraction() {
ysr@777 2214 return recent_avg_survival_fraction_work(_recent_CS_bytes_surviving,
ysr@777 2215 _recent_CS_bytes_used_before);
ysr@777 2216 }
ysr@777 2217
ysr@777 2218 double G1CollectorPolicy::last_survival_fraction() {
ysr@777 2219 return last_survival_fraction_work(_recent_CS_bytes_surviving,
ysr@777 2220 _recent_CS_bytes_used_before);
ysr@777 2221 }
ysr@777 2222
ysr@777 2223 double
ysr@777 2224 G1CollectorPolicy::recent_avg_survival_fraction_work(TruncatedSeq* surviving,
ysr@777 2225 TruncatedSeq* before) {
ysr@777 2226 assert(surviving->num() == before->num(), "Sequence out of sync");
ysr@777 2227 if (before->sum() > 0.0) {
ysr@777 2228 double recent_survival_rate = surviving->sum() / before->sum();
ysr@777 2229 // We exempt parallel collection from this check because Alloc Buffer
ysr@777 2230 // fragmentation can produce negative collections.
ysr@777 2231 // Further, we're now always doing parallel collection. But I'm still
ysr@777 2232 // leaving this here as a placeholder for a more precise assertion later.
ysr@777 2233 // (DLD, 10/05.)
ysr@777 2234 assert((true || ParallelGCThreads > 0) ||
ysr@777 2235 _g1->evacuation_failed() ||
ysr@777 2236 recent_survival_rate <= 1.0, "Or bad frac");
ysr@777 2237 return recent_survival_rate;
ysr@777 2238 } else {
ysr@777 2239 return 1.0; // Be conservative.
ysr@777 2240 }
ysr@777 2241 }
ysr@777 2242
ysr@777 2243 double
ysr@777 2244 G1CollectorPolicy::last_survival_fraction_work(TruncatedSeq* surviving,
ysr@777 2245 TruncatedSeq* before) {
ysr@777 2246 assert(surviving->num() == before->num(), "Sequence out of sync");
ysr@777 2247 if (surviving->num() > 0 && before->last() > 0.0) {
ysr@777 2248 double last_survival_rate = surviving->last() / before->last();
ysr@777 2249 // We exempt parallel collection from this check because Alloc Buffer
ysr@777 2250 // fragmentation can produce negative collections.
ysr@777 2251 // Further, we're now always doing parallel collection. But I'm still
ysr@777 2252 // leaving this here as a placeholder for a more precise assertion later.
ysr@777 2253 // (DLD, 10/05.)
ysr@777 2254 assert((true || ParallelGCThreads > 0) ||
ysr@777 2255 last_survival_rate <= 1.0, "Or bad frac");
ysr@777 2256 return last_survival_rate;
ysr@777 2257 } else {
ysr@777 2258 return 1.0;
ysr@777 2259 }
ysr@777 2260 }
ysr@777 2261
ysr@777 2262 static const int survival_min_obs = 5;
ysr@777 2263 static double survival_min_obs_limits[] = { 0.9, 0.7, 0.5, 0.3, 0.1 };
ysr@777 2264 static const double min_survival_rate = 0.1;
ysr@777 2265
ysr@777 2266 double
ysr@777 2267 G1CollectorPolicy::conservative_avg_survival_fraction_work(double avg,
ysr@777 2268 double latest) {
ysr@777 2269 double res = avg;
ysr@777 2270 if (number_of_recent_gcs() < survival_min_obs) {
ysr@777 2271 res = MAX2(res, survival_min_obs_limits[number_of_recent_gcs()]);
ysr@777 2272 }
ysr@777 2273 res = MAX2(res, latest);
ysr@777 2274 res = MAX2(res, min_survival_rate);
ysr@777 2275 // In the parallel case, LAB fragmentation can produce "negative
ysr@777 2276 // collections"; so can evac failure. Cap at 1.0
ysr@777 2277 res = MIN2(res, 1.0);
ysr@777 2278 return res;
ysr@777 2279 }
ysr@777 2280
ysr@777 2281 size_t G1CollectorPolicy::expansion_amount() {
ysr@777 2282 if ((int)(recent_avg_pause_time_ratio() * 100.0) > G1GCPct) {
ysr@777 2283 // We will double the existing space, or take G1ExpandByPctOfAvail % of
ysr@777 2284 // the available expansion space, whichever is smaller, bounded below
ysr@777 2285 // by a minimum expansion (unless that's all that's left.)
ysr@777 2286 const size_t min_expand_bytes = 1*M;
ysr@777 2287 size_t reserved_bytes = _g1->g1_reserved_obj_bytes();
ysr@777 2288 size_t committed_bytes = _g1->capacity();
ysr@777 2289 size_t uncommitted_bytes = reserved_bytes - committed_bytes;
ysr@777 2290 size_t expand_bytes;
ysr@777 2291 size_t expand_bytes_via_pct =
ysr@777 2292 uncommitted_bytes * G1ExpandByPctOfAvail / 100;
ysr@777 2293 expand_bytes = MIN2(expand_bytes_via_pct, committed_bytes);
ysr@777 2294 expand_bytes = MAX2(expand_bytes, min_expand_bytes);
ysr@777 2295 expand_bytes = MIN2(expand_bytes, uncommitted_bytes);
ysr@777 2296 if (G1PolicyVerbose > 1) {
ysr@777 2297 gclog_or_tty->print("Decided to expand: ratio = %5.2f, "
ysr@777 2298 "committed = %d%s, uncommited = %d%s, via pct = %d%s.\n"
ysr@777 2299 " Answer = %d.\n",
ysr@777 2300 recent_avg_pause_time_ratio(),
ysr@777 2301 byte_size_in_proper_unit(committed_bytes),
ysr@777 2302 proper_unit_for_byte_size(committed_bytes),
ysr@777 2303 byte_size_in_proper_unit(uncommitted_bytes),
ysr@777 2304 proper_unit_for_byte_size(uncommitted_bytes),
ysr@777 2305 byte_size_in_proper_unit(expand_bytes_via_pct),
ysr@777 2306 proper_unit_for_byte_size(expand_bytes_via_pct),
ysr@777 2307 byte_size_in_proper_unit(expand_bytes),
ysr@777 2308 proper_unit_for_byte_size(expand_bytes));
ysr@777 2309 }
ysr@777 2310 return expand_bytes;
ysr@777 2311 } else {
ysr@777 2312 return 0;
ysr@777 2313 }
ysr@777 2314 }
ysr@777 2315
ysr@777 2316 void G1CollectorPolicy::note_start_of_mark_thread() {
ysr@777 2317 _mark_thread_startup_sec = os::elapsedTime();
ysr@777 2318 }
ysr@777 2319
ysr@777 2320 class CountCSClosure: public HeapRegionClosure {
ysr@777 2321 G1CollectorPolicy* _g1_policy;
ysr@777 2322 public:
ysr@777 2323 CountCSClosure(G1CollectorPolicy* g1_policy) :
ysr@777 2324 _g1_policy(g1_policy) {}
ysr@777 2325 bool doHeapRegion(HeapRegion* r) {
ysr@777 2326 _g1_policy->_bytes_in_collection_set_before_gc += r->used();
ysr@777 2327 return false;
ysr@777 2328 }
ysr@777 2329 };
ysr@777 2330
ysr@777 2331 void G1CollectorPolicy::count_CS_bytes_used() {
ysr@777 2332 CountCSClosure cs_closure(this);
ysr@777 2333 _g1->collection_set_iterate(&cs_closure);
ysr@777 2334 }
ysr@777 2335
ysr@777 2336 static void print_indent(int level) {
ysr@777 2337 for (int j = 0; j < level+1; ++j)
ysr@777 2338 gclog_or_tty->print(" ");
ysr@777 2339 }
ysr@777 2340
ysr@777 2341 void G1CollectorPolicy::print_summary (int level,
ysr@777 2342 const char* str,
ysr@777 2343 NumberSeq* seq) const {
ysr@777 2344 double sum = seq->sum();
ysr@777 2345 print_indent(level);
ysr@777 2346 gclog_or_tty->print_cr("%-24s = %8.2lf s (avg = %8.2lf ms)",
ysr@777 2347 str, sum / 1000.0, seq->avg());
ysr@777 2348 }
ysr@777 2349
ysr@777 2350 void G1CollectorPolicy::print_summary_sd (int level,
ysr@777 2351 const char* str,
ysr@777 2352 NumberSeq* seq) const {
ysr@777 2353 print_summary(level, str, seq);
ysr@777 2354 print_indent(level + 5);
ysr@777 2355 gclog_or_tty->print_cr("(num = %5d, std dev = %8.2lf ms, max = %8.2lf ms)",
ysr@777 2356 seq->num(), seq->sd(), seq->maximum());
ysr@777 2357 }
ysr@777 2358
ysr@777 2359 void G1CollectorPolicy::check_other_times(int level,
ysr@777 2360 NumberSeq* other_times_ms,
ysr@777 2361 NumberSeq* calc_other_times_ms) const {
ysr@777 2362 bool should_print = false;
ysr@777 2363
ysr@777 2364 double max_sum = MAX2(fabs(other_times_ms->sum()),
ysr@777 2365 fabs(calc_other_times_ms->sum()));
ysr@777 2366 double min_sum = MIN2(fabs(other_times_ms->sum()),
ysr@777 2367 fabs(calc_other_times_ms->sum()));
ysr@777 2368 double sum_ratio = max_sum / min_sum;
ysr@777 2369 if (sum_ratio > 1.1) {
ysr@777 2370 should_print = true;
ysr@777 2371 print_indent(level + 1);
ysr@777 2372 gclog_or_tty->print_cr("## CALCULATED OTHER SUM DOESN'T MATCH RECORDED ###");
ysr@777 2373 }
ysr@777 2374
ysr@777 2375 double max_avg = MAX2(fabs(other_times_ms->avg()),
ysr@777 2376 fabs(calc_other_times_ms->avg()));
ysr@777 2377 double min_avg = MIN2(fabs(other_times_ms->avg()),
ysr@777 2378 fabs(calc_other_times_ms->avg()));
ysr@777 2379 double avg_ratio = max_avg / min_avg;
ysr@777 2380 if (avg_ratio > 1.1) {
ysr@777 2381 should_print = true;
ysr@777 2382 print_indent(level + 1);
ysr@777 2383 gclog_or_tty->print_cr("## CALCULATED OTHER AVG DOESN'T MATCH RECORDED ###");
ysr@777 2384 }
ysr@777 2385
ysr@777 2386 if (other_times_ms->sum() < -0.01) {
ysr@777 2387 print_indent(level + 1);
ysr@777 2388 gclog_or_tty->print_cr("## RECORDED OTHER SUM IS NEGATIVE ###");
ysr@777 2389 }
ysr@777 2390
ysr@777 2391 if (other_times_ms->avg() < -0.01) {
ysr@777 2392 print_indent(level + 1);
ysr@777 2393 gclog_or_tty->print_cr("## RECORDED OTHER AVG IS NEGATIVE ###");
ysr@777 2394 }
ysr@777 2395
ysr@777 2396 if (calc_other_times_ms->sum() < -0.01) {
ysr@777 2397 should_print = true;
ysr@777 2398 print_indent(level + 1);
ysr@777 2399 gclog_or_tty->print_cr("## CALCULATED OTHER SUM IS NEGATIVE ###");
ysr@777 2400 }
ysr@777 2401
ysr@777 2402 if (calc_other_times_ms->avg() < -0.01) {
ysr@777 2403 should_print = true;
ysr@777 2404 print_indent(level + 1);
ysr@777 2405 gclog_or_tty->print_cr("## CALCULATED OTHER AVG IS NEGATIVE ###");
ysr@777 2406 }
ysr@777 2407
ysr@777 2408 if (should_print)
ysr@777 2409 print_summary(level, "Other(Calc)", calc_other_times_ms);
ysr@777 2410 }
ysr@777 2411
ysr@777 2412 void G1CollectorPolicy::print_summary(PauseSummary* summary) const {
ysr@777 2413 bool parallel = ParallelGCThreads > 0;
ysr@777 2414 MainBodySummary* body_summary = summary->main_body_summary();
ysr@777 2415 PopPreambleSummary* preamble_summary = summary->pop_preamble_summary();
ysr@777 2416
ysr@777 2417 if (summary->get_total_seq()->num() > 0) {
ysr@777 2418 print_summary_sd(0,
ysr@777 2419 (preamble_summary == NULL) ? "Non-Popular Pauses" :
ysr@777 2420 "Popular Pauses",
ysr@777 2421 summary->get_total_seq());
ysr@777 2422 if (preamble_summary != NULL) {
ysr@777 2423 print_summary(1, "Popularity Preamble",
ysr@777 2424 preamble_summary->get_pop_preamble_seq());
ysr@777 2425 print_summary(2, "Update RS", preamble_summary->get_pop_update_rs_seq());
ysr@777 2426 print_summary(2, "Scan RS", preamble_summary->get_pop_scan_rs_seq());
ysr@777 2427 print_summary(2, "Closure App",
ysr@777 2428 preamble_summary->get_pop_closure_app_seq());
ysr@777 2429 print_summary(2, "Evacuation",
ysr@777 2430 preamble_summary->get_pop_evacuation_seq());
ysr@777 2431 print_summary(2, "Other", preamble_summary->get_pop_other_seq());
ysr@777 2432 {
ysr@777 2433 NumberSeq* other_parts[] = {
ysr@777 2434 preamble_summary->get_pop_update_rs_seq(),
ysr@777 2435 preamble_summary->get_pop_scan_rs_seq(),
ysr@777 2436 preamble_summary->get_pop_closure_app_seq(),
ysr@777 2437 preamble_summary->get_pop_evacuation_seq()
ysr@777 2438 };
ysr@777 2439 NumberSeq calc_other_times_ms(preamble_summary->get_pop_preamble_seq(),
ysr@777 2440 4, other_parts);
ysr@777 2441 check_other_times(2, preamble_summary->get_pop_other_seq(),
ysr@777 2442 &calc_other_times_ms);
ysr@777 2443 }
ysr@777 2444 }
ysr@777 2445 if (body_summary != NULL) {
ysr@777 2446 print_summary(1, "SATB Drain", body_summary->get_satb_drain_seq());
ysr@777 2447 if (parallel) {
ysr@777 2448 print_summary(1, "Parallel Time", body_summary->get_parallel_seq());
ysr@777 2449 print_summary(2, "Update RS", body_summary->get_update_rs_seq());
ysr@777 2450 print_summary(2, "Ext Root Scanning",
ysr@777 2451 body_summary->get_ext_root_scan_seq());
ysr@777 2452 print_summary(2, "Mark Stack Scanning",
ysr@777 2453 body_summary->get_mark_stack_scan_seq());
ysr@777 2454 print_summary(2, "Scan-Only Scanning",
ysr@777 2455 body_summary->get_scan_only_seq());
ysr@777 2456 print_summary(2, "Scan RS", body_summary->get_scan_rs_seq());
ysr@777 2457 print_summary(2, "Object Copy", body_summary->get_obj_copy_seq());
ysr@777 2458 print_summary(2, "Termination", body_summary->get_termination_seq());
ysr@777 2459 print_summary(2, "Other", body_summary->get_parallel_other_seq());
ysr@777 2460 {
ysr@777 2461 NumberSeq* other_parts[] = {
ysr@777 2462 body_summary->get_update_rs_seq(),
ysr@777 2463 body_summary->get_ext_root_scan_seq(),
ysr@777 2464 body_summary->get_mark_stack_scan_seq(),
ysr@777 2465 body_summary->get_scan_only_seq(),
ysr@777 2466 body_summary->get_scan_rs_seq(),
ysr@777 2467 body_summary->get_obj_copy_seq(),
ysr@777 2468 body_summary->get_termination_seq()
ysr@777 2469 };
ysr@777 2470 NumberSeq calc_other_times_ms(body_summary->get_parallel_seq(),
ysr@777 2471 7, other_parts);
ysr@777 2472 check_other_times(2, body_summary->get_parallel_other_seq(),
ysr@777 2473 &calc_other_times_ms);
ysr@777 2474 }
ysr@777 2475 print_summary(1, "Mark Closure", body_summary->get_mark_closure_seq());
ysr@777 2476 print_summary(1, "Clear CT", body_summary->get_clear_ct_seq());
ysr@777 2477 } else {
ysr@777 2478 print_summary(1, "Update RS", body_summary->get_update_rs_seq());
ysr@777 2479 print_summary(1, "Ext Root Scanning",
ysr@777 2480 body_summary->get_ext_root_scan_seq());
ysr@777 2481 print_summary(1, "Mark Stack Scanning",
ysr@777 2482 body_summary->get_mark_stack_scan_seq());
ysr@777 2483 print_summary(1, "Scan-Only Scanning",
ysr@777 2484 body_summary->get_scan_only_seq());
ysr@777 2485 print_summary(1, "Scan RS", body_summary->get_scan_rs_seq());
ysr@777 2486 print_summary(1, "Object Copy", body_summary->get_obj_copy_seq());
ysr@777 2487 }
ysr@777 2488 }
ysr@777 2489 print_summary(1, "Other", summary->get_other_seq());
ysr@777 2490 {
ysr@777 2491 NumberSeq calc_other_times_ms;
ysr@777 2492 if (body_summary != NULL) {
ysr@777 2493 // not abandoned
ysr@777 2494 if (parallel) {
ysr@777 2495 // parallel
ysr@777 2496 NumberSeq* other_parts[] = {
ysr@777 2497 body_summary->get_satb_drain_seq(),
ysr@777 2498 (preamble_summary == NULL) ? NULL :
ysr@777 2499 preamble_summary->get_pop_preamble_seq(),
ysr@777 2500 body_summary->get_parallel_seq(),
ysr@777 2501 body_summary->get_clear_ct_seq()
ysr@777 2502 };
ysr@777 2503 calc_other_times_ms = NumberSeq (summary->get_total_seq(),
ysr@777 2504 4, other_parts);
ysr@777 2505 } else {
ysr@777 2506 // serial
ysr@777 2507 NumberSeq* other_parts[] = {
ysr@777 2508 body_summary->get_satb_drain_seq(),
ysr@777 2509 (preamble_summary == NULL) ? NULL :
ysr@777 2510 preamble_summary->get_pop_preamble_seq(),
ysr@777 2511 body_summary->get_update_rs_seq(),
ysr@777 2512 body_summary->get_ext_root_scan_seq(),
ysr@777 2513 body_summary->get_mark_stack_scan_seq(),
ysr@777 2514 body_summary->get_scan_only_seq(),
ysr@777 2515 body_summary->get_scan_rs_seq(),
ysr@777 2516 body_summary->get_obj_copy_seq()
ysr@777 2517 };
ysr@777 2518 calc_other_times_ms = NumberSeq(summary->get_total_seq(),
ysr@777 2519 8, other_parts);
ysr@777 2520 }
ysr@777 2521 } else {
ysr@777 2522 // abandoned
ysr@777 2523 NumberSeq* other_parts[] = {
ysr@777 2524 (preamble_summary == NULL) ? NULL :
ysr@777 2525 preamble_summary->get_pop_preamble_seq()
ysr@777 2526 };
ysr@777 2527 calc_other_times_ms = NumberSeq(summary->get_total_seq(),
ysr@777 2528 1, other_parts);
ysr@777 2529 }
ysr@777 2530 check_other_times(1, summary->get_other_seq(), &calc_other_times_ms);
ysr@777 2531 }
ysr@777 2532 } else {
ysr@777 2533 print_indent(0);
ysr@777 2534 gclog_or_tty->print_cr("none");
ysr@777 2535 }
ysr@777 2536 gclog_or_tty->print_cr("");
ysr@777 2537 }
ysr@777 2538
ysr@777 2539 void
ysr@777 2540 G1CollectorPolicy::print_abandoned_summary(PauseSummary* non_pop_summary,
ysr@777 2541 PauseSummary* pop_summary) const {
ysr@777 2542 bool printed = false;
ysr@777 2543 if (non_pop_summary->get_total_seq()->num() > 0) {
ysr@777 2544 printed = true;
ysr@777 2545 print_summary(non_pop_summary);
ysr@777 2546 }
ysr@777 2547 if (pop_summary->get_total_seq()->num() > 0) {
ysr@777 2548 printed = true;
ysr@777 2549 print_summary(pop_summary);
ysr@777 2550 }
ysr@777 2551
ysr@777 2552 if (!printed) {
ysr@777 2553 print_indent(0);
ysr@777 2554 gclog_or_tty->print_cr("none");
ysr@777 2555 gclog_or_tty->print_cr("");
ysr@777 2556 }
ysr@777 2557 }
ysr@777 2558
ysr@777 2559 void G1CollectorPolicy::print_tracing_info() const {
ysr@777 2560 if (TraceGen0Time) {
ysr@777 2561 gclog_or_tty->print_cr("ALL PAUSES");
ysr@777 2562 print_summary_sd(0, "Total", _all_pause_times_ms);
ysr@777 2563 gclog_or_tty->print_cr("");
ysr@777 2564 gclog_or_tty->print_cr("");
ysr@777 2565 gclog_or_tty->print_cr(" Full Young GC Pauses: %8d", _full_young_pause_num);
ysr@777 2566 gclog_or_tty->print_cr(" Partial Young GC Pauses: %8d", _partial_young_pause_num);
ysr@777 2567 gclog_or_tty->print_cr("");
ysr@777 2568
ysr@777 2569 gclog_or_tty->print_cr("NON-POPULAR PAUSES");
ysr@777 2570 print_summary(_non_pop_summary);
ysr@777 2571
ysr@777 2572 gclog_or_tty->print_cr("POPULAR PAUSES");
ysr@777 2573 print_summary(_pop_summary);
ysr@777 2574
ysr@777 2575 gclog_or_tty->print_cr("ABANDONED PAUSES");
ysr@777 2576 print_abandoned_summary(_non_pop_abandoned_summary,
ysr@777 2577 _pop_abandoned_summary);
ysr@777 2578
ysr@777 2579 gclog_or_tty->print_cr("MISC");
ysr@777 2580 print_summary_sd(0, "Stop World", _all_stop_world_times_ms);
ysr@777 2581 print_summary_sd(0, "Yields", _all_yield_times_ms);
ysr@777 2582 for (int i = 0; i < _aux_num; ++i) {
ysr@777 2583 if (_all_aux_times_ms[i].num() > 0) {
ysr@777 2584 char buffer[96];
ysr@777 2585 sprintf(buffer, "Aux%d", i);
ysr@777 2586 print_summary_sd(0, buffer, &_all_aux_times_ms[i]);
ysr@777 2587 }
ysr@777 2588 }
ysr@777 2589
ysr@777 2590 size_t all_region_num = _region_num_young + _region_num_tenured;
ysr@777 2591 gclog_or_tty->print_cr(" New Regions %8d, Young %8d (%6.2lf%%), "
ysr@777 2592 "Tenured %8d (%6.2lf%%)",
ysr@777 2593 all_region_num,
ysr@777 2594 _region_num_young,
ysr@777 2595 (double) _region_num_young / (double) all_region_num * 100.0,
ysr@777 2596 _region_num_tenured,
ysr@777 2597 (double) _region_num_tenured / (double) all_region_num * 100.0);
ysr@777 2598
ysr@777 2599 if (!G1RSBarrierUseQueue) {
ysr@777 2600 gclog_or_tty->print_cr("Of %d times conc refinement was enabled, %d (%7.2f%%) "
ysr@777 2601 "did zero traversals.",
ysr@777 2602 _conc_refine_enabled, _conc_refine_zero_traversals,
ysr@777 2603 _conc_refine_enabled > 0 ?
ysr@777 2604 100.0 * (float)_conc_refine_zero_traversals/
ysr@777 2605 (float)_conc_refine_enabled : 0.0);
ysr@777 2606 gclog_or_tty->print_cr(" Max # of traversals = %d.",
ysr@777 2607 _conc_refine_max_traversals);
ysr@777 2608 gclog_or_tty->print_cr("");
ysr@777 2609 }
ysr@777 2610 }
ysr@777 2611 if (TraceGen1Time) {
ysr@777 2612 if (_all_full_gc_times_ms->num() > 0) {
ysr@777 2613 gclog_or_tty->print("\n%4d full_gcs: total time = %8.2f s",
ysr@777 2614 _all_full_gc_times_ms->num(),
ysr@777 2615 _all_full_gc_times_ms->sum() / 1000.0);
ysr@777 2616 gclog_or_tty->print_cr(" (avg = %8.2fms).", _all_full_gc_times_ms->avg());
ysr@777 2617 gclog_or_tty->print_cr(" [std. dev = %8.2f ms, max = %8.2f ms]",
ysr@777 2618 _all_full_gc_times_ms->sd(),
ysr@777 2619 _all_full_gc_times_ms->maximum());
ysr@777 2620 }
ysr@777 2621 }
ysr@777 2622 }
ysr@777 2623
ysr@777 2624 void G1CollectorPolicy::print_yg_surv_rate_info() const {
ysr@777 2625 #ifndef PRODUCT
ysr@777 2626 _short_lived_surv_rate_group->print_surv_rate_summary();
ysr@777 2627 // add this call for any other surv rate groups
ysr@777 2628 #endif // PRODUCT
ysr@777 2629 }
ysr@777 2630
ysr@777 2631 void G1CollectorPolicy::update_conc_refine_data() {
ysr@777 2632 unsigned traversals = _g1->concurrent_g1_refine()->disable();
ysr@777 2633 if (traversals == 0) _conc_refine_zero_traversals++;
ysr@777 2634 _conc_refine_max_traversals = MAX2(_conc_refine_max_traversals,
ysr@777 2635 (size_t)traversals);
ysr@777 2636
ysr@777 2637 if (G1PolicyVerbose > 1)
ysr@777 2638 gclog_or_tty->print_cr("Did a CR traversal series: %d traversals.", traversals);
ysr@777 2639 double multiplier = 1.0;
ysr@777 2640 if (traversals == 0) {
ysr@777 2641 multiplier = 4.0;
ysr@777 2642 } else if (traversals > (size_t)G1ConcRefineTargTraversals) {
ysr@777 2643 multiplier = 1.0/1.5;
ysr@777 2644 } else if (traversals < (size_t)G1ConcRefineTargTraversals) {
ysr@777 2645 multiplier = 1.5;
ysr@777 2646 }
ysr@777 2647 if (G1PolicyVerbose > 1) {
ysr@777 2648 gclog_or_tty->print_cr(" Multiplier = %7.2f.", multiplier);
ysr@777 2649 gclog_or_tty->print(" Delta went from %d regions to ",
ysr@777 2650 _conc_refine_current_delta);
ysr@777 2651 }
ysr@777 2652 _conc_refine_current_delta =
ysr@777 2653 MIN2(_g1->n_regions(),
ysr@777 2654 (size_t)(_conc_refine_current_delta * multiplier));
ysr@777 2655 _conc_refine_current_delta =
ysr@777 2656 MAX2(_conc_refine_current_delta, (size_t)1);
ysr@777 2657 if (G1PolicyVerbose > 1) {
ysr@777 2658 gclog_or_tty->print_cr("%d regions.", _conc_refine_current_delta);
ysr@777 2659 }
ysr@777 2660 _conc_refine_enabled++;
ysr@777 2661 }
ysr@777 2662
ysr@777 2663 void G1CollectorPolicy::set_single_region_collection_set(HeapRegion* hr) {
ysr@777 2664 assert(collection_set() == NULL, "Must be no current CS.");
ysr@777 2665 _collection_set_size = 0;
ysr@777 2666 _collection_set_bytes_used_before = 0;
ysr@777 2667 add_to_collection_set(hr);
ysr@777 2668 count_CS_bytes_used();
ysr@777 2669 }
ysr@777 2670
ysr@777 2671 bool
ysr@777 2672 G1CollectorPolicy::should_add_next_region_to_young_list() {
ysr@777 2673 assert(in_young_gc_mode(), "should be in young GC mode");
ysr@777 2674 bool ret;
ysr@777 2675 size_t young_list_length = _g1->young_list_length();
ysr@777 2676
ysr@777 2677 if (young_list_length < _young_list_target_length) {
ysr@777 2678 ret = true;
ysr@777 2679 ++_region_num_young;
ysr@777 2680 } else {
ysr@777 2681 ret = false;
ysr@777 2682 ++_region_num_tenured;
ysr@777 2683 }
ysr@777 2684
ysr@777 2685 return ret;
ysr@777 2686 }
ysr@777 2687
ysr@777 2688 #ifndef PRODUCT
ysr@777 2689 // for debugging, bit of a hack...
ysr@777 2690 static char*
ysr@777 2691 region_num_to_mbs(int length) {
ysr@777 2692 static char buffer[64];
ysr@777 2693 double bytes = (double) (length * HeapRegion::GrainBytes);
ysr@777 2694 double mbs = bytes / (double) (1024 * 1024);
ysr@777 2695 sprintf(buffer, "%7.2lfMB", mbs);
ysr@777 2696 return buffer;
ysr@777 2697 }
ysr@777 2698 #endif // PRODUCT
ysr@777 2699
ysr@777 2700 void
ysr@777 2701 G1CollectorPolicy::checkpoint_conc_overhead() {
ysr@777 2702 double conc_overhead = 0.0;
ysr@777 2703 if (G1AccountConcurrentOverhead)
ysr@777 2704 conc_overhead = COTracker::totalPredConcOverhead();
ysr@777 2705 _mmu_tracker->update_conc_overhead(conc_overhead);
ysr@777 2706 #if 0
ysr@777 2707 gclog_or_tty->print(" CO %1.4lf TARGET %1.4lf",
ysr@777 2708 conc_overhead, _mmu_tracker->max_gc_time());
ysr@777 2709 #endif
ysr@777 2710 }
ysr@777 2711
ysr@777 2712
ysr@777 2713 uint G1CollectorPolicy::max_regions(int purpose) {
ysr@777 2714 switch (purpose) {
ysr@777 2715 case GCAllocForSurvived:
ysr@777 2716 return G1MaxSurvivorRegions;
ysr@777 2717 case GCAllocForTenured:
ysr@777 2718 return UINT_MAX;
ysr@777 2719 default:
ysr@777 2720 return UINT_MAX;
ysr@777 2721 };
ysr@777 2722 }
ysr@777 2723
ysr@777 2724 void
ysr@777 2725 G1CollectorPolicy_BestRegionsFirst::
ysr@777 2726 set_single_region_collection_set(HeapRegion* hr) {
ysr@777 2727 G1CollectorPolicy::set_single_region_collection_set(hr);
ysr@777 2728 _collectionSetChooser->removeRegion(hr);
ysr@777 2729 }
ysr@777 2730
ysr@777 2731
ysr@777 2732 bool
ysr@777 2733 G1CollectorPolicy_BestRegionsFirst::should_do_collection_pause(size_t
ysr@777 2734 word_size) {
ysr@777 2735 assert(_g1->regions_accounted_for(), "Region leakage!");
ysr@777 2736 // Initiate a pause when we reach the steady-state "used" target.
ysr@777 2737 size_t used_hard = (_g1->capacity() / 100) * G1SteadyStateUsed;
ysr@777 2738 size_t used_soft =
ysr@777 2739 MAX2((_g1->capacity() / 100) * (G1SteadyStateUsed - G1SteadyStateUsedDelta),
ysr@777 2740 used_hard/2);
ysr@777 2741 size_t used = _g1->used();
ysr@777 2742
ysr@777 2743 double max_pause_time_ms = _mmu_tracker->max_gc_time() * 1000.0;
ysr@777 2744
ysr@777 2745 size_t young_list_length = _g1->young_list_length();
ysr@777 2746 bool reached_target_length = young_list_length >= _young_list_target_length;
ysr@777 2747
ysr@777 2748 if (in_young_gc_mode()) {
ysr@777 2749 if (reached_target_length) {
ysr@777 2750 assert( young_list_length > 0 && _g1->young_list_length() > 0,
ysr@777 2751 "invariant" );
ysr@777 2752 _target_pause_time_ms = max_pause_time_ms;
ysr@777 2753 return true;
ysr@777 2754 }
ysr@777 2755 } else {
ysr@777 2756 guarantee( false, "should not reach here" );
ysr@777 2757 }
ysr@777 2758
ysr@777 2759 return false;
ysr@777 2760 }
ysr@777 2761
ysr@777 2762 #ifndef PRODUCT
ysr@777 2763 class HRSortIndexIsOKClosure: public HeapRegionClosure {
ysr@777 2764 CollectionSetChooser* _chooser;
ysr@777 2765 public:
ysr@777 2766 HRSortIndexIsOKClosure(CollectionSetChooser* chooser) :
ysr@777 2767 _chooser(chooser) {}
ysr@777 2768
ysr@777 2769 bool doHeapRegion(HeapRegion* r) {
ysr@777 2770 if (!r->continuesHumongous()) {
ysr@777 2771 assert(_chooser->regionProperlyOrdered(r), "Ought to be.");
ysr@777 2772 }
ysr@777 2773 return false;
ysr@777 2774 }
ysr@777 2775 };
ysr@777 2776
ysr@777 2777 bool G1CollectorPolicy_BestRegionsFirst::assertMarkedBytesDataOK() {
ysr@777 2778 HRSortIndexIsOKClosure cl(_collectionSetChooser);
ysr@777 2779 _g1->heap_region_iterate(&cl);
ysr@777 2780 return true;
ysr@777 2781 }
ysr@777 2782 #endif
ysr@777 2783
ysr@777 2784 void
ysr@777 2785 G1CollectorPolicy_BestRegionsFirst::
ysr@777 2786 record_collection_pause_start(double start_time_sec, size_t start_used) {
ysr@777 2787 G1CollectorPolicy::record_collection_pause_start(start_time_sec, start_used);
ysr@777 2788 }
ysr@777 2789
ysr@777 2790 class NextNonCSElemFinder: public HeapRegionClosure {
ysr@777 2791 HeapRegion* _res;
ysr@777 2792 public:
ysr@777 2793 NextNonCSElemFinder(): _res(NULL) {}
ysr@777 2794 bool doHeapRegion(HeapRegion* r) {
ysr@777 2795 if (!r->in_collection_set()) {
ysr@777 2796 _res = r;
ysr@777 2797 return true;
ysr@777 2798 } else {
ysr@777 2799 return false;
ysr@777 2800 }
ysr@777 2801 }
ysr@777 2802 HeapRegion* res() { return _res; }
ysr@777 2803 };
ysr@777 2804
ysr@777 2805 class KnownGarbageClosure: public HeapRegionClosure {
ysr@777 2806 CollectionSetChooser* _hrSorted;
ysr@777 2807
ysr@777 2808 public:
ysr@777 2809 KnownGarbageClosure(CollectionSetChooser* hrSorted) :
ysr@777 2810 _hrSorted(hrSorted)
ysr@777 2811 {}
ysr@777 2812
ysr@777 2813 bool doHeapRegion(HeapRegion* r) {
ysr@777 2814 // We only include humongous regions in collection
ysr@777 2815 // sets when concurrent mark shows that their contained object is
ysr@777 2816 // unreachable.
ysr@777 2817
ysr@777 2818 // Do we have any marking information for this region?
ysr@777 2819 if (r->is_marked()) {
ysr@777 2820 // We don't include humongous regions in collection
ysr@777 2821 // sets because we collect them immediately at the end of a marking
ysr@777 2822 // cycle. We also don't include young regions because we *must*
ysr@777 2823 // include them in the next collection pause.
ysr@777 2824 if (!r->isHumongous() && !r->is_young()) {
ysr@777 2825 _hrSorted->addMarkedHeapRegion(r);
ysr@777 2826 }
ysr@777 2827 }
ysr@777 2828 return false;
ysr@777 2829 }
ysr@777 2830 };
ysr@777 2831
ysr@777 2832 class ParKnownGarbageHRClosure: public HeapRegionClosure {
ysr@777 2833 CollectionSetChooser* _hrSorted;
ysr@777 2834 jint _marked_regions_added;
ysr@777 2835 jint _chunk_size;
ysr@777 2836 jint _cur_chunk_idx;
ysr@777 2837 jint _cur_chunk_end; // Cur chunk [_cur_chunk_idx, _cur_chunk_end)
ysr@777 2838 int _worker;
ysr@777 2839 int _invokes;
ysr@777 2840
ysr@777 2841 void get_new_chunk() {
ysr@777 2842 _cur_chunk_idx = _hrSorted->getParMarkedHeapRegionChunk(_chunk_size);
ysr@777 2843 _cur_chunk_end = _cur_chunk_idx + _chunk_size;
ysr@777 2844 }
ysr@777 2845 void add_region(HeapRegion* r) {
ysr@777 2846 if (_cur_chunk_idx == _cur_chunk_end) {
ysr@777 2847 get_new_chunk();
ysr@777 2848 }
ysr@777 2849 assert(_cur_chunk_idx < _cur_chunk_end, "postcondition");
ysr@777 2850 _hrSorted->setMarkedHeapRegion(_cur_chunk_idx, r);
ysr@777 2851 _marked_regions_added++;
ysr@777 2852 _cur_chunk_idx++;
ysr@777 2853 }
ysr@777 2854
ysr@777 2855 public:
ysr@777 2856 ParKnownGarbageHRClosure(CollectionSetChooser* hrSorted,
ysr@777 2857 jint chunk_size,
ysr@777 2858 int worker) :
ysr@777 2859 _hrSorted(hrSorted), _chunk_size(chunk_size), _worker(worker),
ysr@777 2860 _marked_regions_added(0), _cur_chunk_idx(0), _cur_chunk_end(0),
ysr@777 2861 _invokes(0)
ysr@777 2862 {}
ysr@777 2863
ysr@777 2864 bool doHeapRegion(HeapRegion* r) {
ysr@777 2865 // We only include humongous regions in collection
ysr@777 2866 // sets when concurrent mark shows that their contained object is
ysr@777 2867 // unreachable.
ysr@777 2868 _invokes++;
ysr@777 2869
ysr@777 2870 // Do we have any marking information for this region?
ysr@777 2871 if (r->is_marked()) {
ysr@777 2872 // We don't include humongous regions in collection
ysr@777 2873 // sets because we collect them immediately at the end of a marking
ysr@777 2874 // cycle.
ysr@777 2875 // We also do not include young regions in collection sets
ysr@777 2876 if (!r->isHumongous() && !r->is_young()) {
ysr@777 2877 add_region(r);
ysr@777 2878 }
ysr@777 2879 }
ysr@777 2880 return false;
ysr@777 2881 }
ysr@777 2882 jint marked_regions_added() { return _marked_regions_added; }
ysr@777 2883 int invokes() { return _invokes; }
ysr@777 2884 };
ysr@777 2885
ysr@777 2886 class ParKnownGarbageTask: public AbstractGangTask {
ysr@777 2887 CollectionSetChooser* _hrSorted;
ysr@777 2888 jint _chunk_size;
ysr@777 2889 G1CollectedHeap* _g1;
ysr@777 2890 public:
ysr@777 2891 ParKnownGarbageTask(CollectionSetChooser* hrSorted, jint chunk_size) :
ysr@777 2892 AbstractGangTask("ParKnownGarbageTask"),
ysr@777 2893 _hrSorted(hrSorted), _chunk_size(chunk_size),
ysr@777 2894 _g1(G1CollectedHeap::heap())
ysr@777 2895 {}
ysr@777 2896
ysr@777 2897 void work(int i) {
ysr@777 2898 ParKnownGarbageHRClosure parKnownGarbageCl(_hrSorted, _chunk_size, i);
ysr@777 2899 // Back to zero for the claim value.
ysr@777 2900 _g1->heap_region_par_iterate_chunked(&parKnownGarbageCl, i, 0);
ysr@777 2901 jint regions_added = parKnownGarbageCl.marked_regions_added();
ysr@777 2902 _hrSorted->incNumMarkedHeapRegions(regions_added);
ysr@777 2903 if (G1PrintParCleanupStats) {
ysr@777 2904 gclog_or_tty->print(" Thread %d called %d times, added %d regions to list.\n",
ysr@777 2905 i, parKnownGarbageCl.invokes(), regions_added);
ysr@777 2906 }
ysr@777 2907 }
ysr@777 2908 };
ysr@777 2909
ysr@777 2910 void
ysr@777 2911 G1CollectorPolicy_BestRegionsFirst::
ysr@777 2912 record_concurrent_mark_cleanup_end(size_t freed_bytes,
ysr@777 2913 size_t max_live_bytes) {
ysr@777 2914 double start;
ysr@777 2915 if (G1PrintParCleanupStats) start = os::elapsedTime();
ysr@777 2916 record_concurrent_mark_cleanup_end_work1(freed_bytes, max_live_bytes);
ysr@777 2917
ysr@777 2918 _collectionSetChooser->clearMarkedHeapRegions();
ysr@777 2919 double clear_marked_end;
ysr@777 2920 if (G1PrintParCleanupStats) {
ysr@777 2921 clear_marked_end = os::elapsedTime();
ysr@777 2922 gclog_or_tty->print_cr(" clear marked regions + work1: %8.3f ms.",
ysr@777 2923 (clear_marked_end - start)*1000.0);
ysr@777 2924 }
ysr@777 2925 if (ParallelGCThreads > 0) {
ysr@777 2926 const size_t OverpartitionFactor = 4;
ysr@777 2927 const size_t MinChunkSize = 8;
ysr@777 2928 const size_t ChunkSize =
ysr@777 2929 MAX2(_g1->n_regions() / (ParallelGCThreads * OverpartitionFactor),
ysr@777 2930 MinChunkSize);
ysr@777 2931 _collectionSetChooser->prepareForAddMarkedHeapRegionsPar(_g1->n_regions(),
ysr@777 2932 ChunkSize);
ysr@777 2933 ParKnownGarbageTask parKnownGarbageTask(_collectionSetChooser,
ysr@777 2934 (int) ChunkSize);
ysr@777 2935 _g1->workers()->run_task(&parKnownGarbageTask);
ysr@777 2936 } else {
ysr@777 2937 KnownGarbageClosure knownGarbagecl(_collectionSetChooser);
ysr@777 2938 _g1->heap_region_iterate(&knownGarbagecl);
ysr@777 2939 }
ysr@777 2940 double known_garbage_end;
ysr@777 2941 if (G1PrintParCleanupStats) {
ysr@777 2942 known_garbage_end = os::elapsedTime();
ysr@777 2943 gclog_or_tty->print_cr(" compute known garbage: %8.3f ms.",
ysr@777 2944 (known_garbage_end - clear_marked_end)*1000.0);
ysr@777 2945 }
ysr@777 2946 _collectionSetChooser->sortMarkedHeapRegions();
ysr@777 2947 double sort_end;
ysr@777 2948 if (G1PrintParCleanupStats) {
ysr@777 2949 sort_end = os::elapsedTime();
ysr@777 2950 gclog_or_tty->print_cr(" sorting: %8.3f ms.",
ysr@777 2951 (sort_end - known_garbage_end)*1000.0);
ysr@777 2952 }
ysr@777 2953
ysr@777 2954 record_concurrent_mark_cleanup_end_work2();
ysr@777 2955 double work2_end;
ysr@777 2956 if (G1PrintParCleanupStats) {
ysr@777 2957 work2_end = os::elapsedTime();
ysr@777 2958 gclog_or_tty->print_cr(" work2: %8.3f ms.",
ysr@777 2959 (work2_end - sort_end)*1000.0);
ysr@777 2960 }
ysr@777 2961 }
ysr@777 2962
ysr@777 2963 // Add the heap region to the collection set and return the conservative
ysr@777 2964 // estimate of the number of live bytes.
ysr@777 2965 void G1CollectorPolicy::
ysr@777 2966 add_to_collection_set(HeapRegion* hr) {
ysr@777 2967 if (G1TraceRegions) {
ysr@777 2968 gclog_or_tty->print_cr("added region to cset %d:["PTR_FORMAT", "PTR_FORMAT"], "
ysr@777 2969 "top "PTR_FORMAT", young %s",
ysr@777 2970 hr->hrs_index(), hr->bottom(), hr->end(),
ysr@777 2971 hr->top(), (hr->is_young()) ? "YES" : "NO");
ysr@777 2972 }
ysr@777 2973
ysr@777 2974 if (_g1->mark_in_progress())
ysr@777 2975 _g1->concurrent_mark()->registerCSetRegion(hr);
ysr@777 2976
ysr@777 2977 assert(!hr->in_collection_set(),
ysr@777 2978 "should not already be in the CSet");
ysr@777 2979 hr->set_in_collection_set(true);
ysr@777 2980 hr->set_next_in_collection_set(_collection_set);
ysr@777 2981 _collection_set = hr;
ysr@777 2982 _collection_set_size++;
ysr@777 2983 _collection_set_bytes_used_before += hr->used();
ysr@777 2984 }
ysr@777 2985
ysr@777 2986 void
ysr@777 2987 G1CollectorPolicy_BestRegionsFirst::
ysr@777 2988 choose_collection_set(HeapRegion* pop_region) {
ysr@777 2989 double non_young_start_time_sec;
ysr@777 2990 start_recording_regions();
ysr@777 2991
ysr@777 2992 if (pop_region != NULL) {
ysr@777 2993 _target_pause_time_ms = (double) G1MaxPauseTimeMS;
ysr@777 2994 } else {
ysr@777 2995 guarantee(_target_pause_time_ms > -1.0,
ysr@777 2996 "_target_pause_time_ms should have been set!");
ysr@777 2997 }
ysr@777 2998
ysr@777 2999 // pop region is either null (and so is CS), or else it *is* the CS.
ysr@777 3000 assert(_collection_set == pop_region, "Precondition");
ysr@777 3001
ysr@777 3002 double base_time_ms = predict_base_elapsed_time_ms(_pending_cards);
ysr@777 3003 double predicted_pause_time_ms = base_time_ms;
ysr@777 3004
ysr@777 3005 double target_time_ms = _target_pause_time_ms;
ysr@777 3006 double time_remaining_ms = target_time_ms - base_time_ms;
ysr@777 3007
ysr@777 3008 // the 10% and 50% values are arbitrary...
ysr@777 3009 if (time_remaining_ms < 0.10*target_time_ms) {
ysr@777 3010 time_remaining_ms = 0.50 * target_time_ms;
ysr@777 3011 _within_target = false;
ysr@777 3012 } else {
ysr@777 3013 _within_target = true;
ysr@777 3014 }
ysr@777 3015
ysr@777 3016 // We figure out the number of bytes available for future to-space.
ysr@777 3017 // For new regions without marking information, we must assume the
ysr@777 3018 // worst-case of complete survival. If we have marking information for a
ysr@777 3019 // region, we can bound the amount of live data. We can add a number of
ysr@777 3020 // such regions, as long as the sum of the live data bounds does not
ysr@777 3021 // exceed the available evacuation space.
ysr@777 3022 size_t max_live_bytes = _g1->free_regions() * HeapRegion::GrainBytes;
ysr@777 3023
ysr@777 3024 size_t expansion_bytes =
ysr@777 3025 _g1->expansion_regions() * HeapRegion::GrainBytes;
ysr@777 3026
ysr@777 3027 if (pop_region == NULL) {
ysr@777 3028 _collection_set_bytes_used_before = 0;
ysr@777 3029 _collection_set_size = 0;
ysr@777 3030 }
ysr@777 3031
ysr@777 3032 // Adjust for expansion and slop.
ysr@777 3033 max_live_bytes = max_live_bytes + expansion_bytes;
ysr@777 3034
ysr@777 3035 assert(pop_region != NULL || _g1->regions_accounted_for(), "Region leakage!");
ysr@777 3036
ysr@777 3037 HeapRegion* hr;
ysr@777 3038 if (in_young_gc_mode()) {
ysr@777 3039 double young_start_time_sec = os::elapsedTime();
ysr@777 3040
ysr@777 3041 if (G1PolicyVerbose > 0) {
ysr@777 3042 gclog_or_tty->print_cr("Adding %d young regions to the CSet",
ysr@777 3043 _g1->young_list_length());
ysr@777 3044 }
ysr@777 3045 _young_cset_length = 0;
ysr@777 3046 _last_young_gc_full = full_young_gcs() ? true : false;
ysr@777 3047 if (_last_young_gc_full)
ysr@777 3048 ++_full_young_pause_num;
ysr@777 3049 else
ysr@777 3050 ++_partial_young_pause_num;
ysr@777 3051 hr = _g1->pop_region_from_young_list();
ysr@777 3052 while (hr != NULL) {
ysr@777 3053
ysr@777 3054 assert( hr->young_index_in_cset() == -1, "invariant" );
ysr@777 3055 assert( hr->age_in_surv_rate_group() != -1, "invariant" );
ysr@777 3056 hr->set_young_index_in_cset((int) _young_cset_length);
ysr@777 3057
ysr@777 3058 ++_young_cset_length;
ysr@777 3059 double predicted_time_ms = predict_region_elapsed_time_ms(hr, true);
ysr@777 3060 time_remaining_ms -= predicted_time_ms;
ysr@777 3061 predicted_pause_time_ms += predicted_time_ms;
ysr@777 3062 if (hr == pop_region) {
ysr@777 3063 // The popular region was young. Skip over it.
ysr@777 3064 assert(hr->in_collection_set(), "It's the pop region.");
ysr@777 3065 } else {
ysr@777 3066 assert(!hr->in_collection_set(), "It's not the pop region.");
ysr@777 3067 add_to_collection_set(hr);
ysr@777 3068 record_cset_region(hr, true);
ysr@777 3069 }
ysr@777 3070 max_live_bytes -= MIN2(hr->max_live_bytes(), max_live_bytes);
ysr@777 3071 if (G1PolicyVerbose > 0) {
ysr@777 3072 gclog_or_tty->print_cr(" Added [" PTR_FORMAT ", " PTR_FORMAT") to CS.",
ysr@777 3073 hr->bottom(), hr->end());
ysr@777 3074 gclog_or_tty->print_cr(" (" SIZE_FORMAT " KB left in heap.)",
ysr@777 3075 max_live_bytes/K);
ysr@777 3076 }
ysr@777 3077 hr = _g1->pop_region_from_young_list();
ysr@777 3078 }
ysr@777 3079
ysr@777 3080 record_scan_only_regions(_g1->young_list_scan_only_length());
ysr@777 3081
ysr@777 3082 double young_end_time_sec = os::elapsedTime();
ysr@777 3083 _recorded_young_cset_choice_time_ms =
ysr@777 3084 (young_end_time_sec - young_start_time_sec) * 1000.0;
ysr@777 3085
ysr@777 3086 non_young_start_time_sec = os::elapsedTime();
ysr@777 3087
ysr@777 3088 if (_young_cset_length > 0 && _last_young_gc_full) {
ysr@777 3089 // don't bother adding more regions...
ysr@777 3090 goto choose_collection_set_end;
ysr@777 3091 }
ysr@777 3092 } else if (pop_region != NULL) {
ysr@777 3093 // We're not in young mode, and we chose a popular region; don't choose
ysr@777 3094 // any more.
ysr@777 3095 return;
ysr@777 3096 }
ysr@777 3097
ysr@777 3098 if (!in_young_gc_mode() || !full_young_gcs()) {
ysr@777 3099 bool should_continue = true;
ysr@777 3100 NumberSeq seq;
ysr@777 3101 double avg_prediction = 100000000000000000.0; // something very large
ysr@777 3102 do {
ysr@777 3103 hr = _collectionSetChooser->getNextMarkedRegion(time_remaining_ms,
ysr@777 3104 avg_prediction);
ysr@777 3105 if (hr != NULL && !hr->popular()) {
ysr@777 3106 double predicted_time_ms = predict_region_elapsed_time_ms(hr, false);
ysr@777 3107 time_remaining_ms -= predicted_time_ms;
ysr@777 3108 predicted_pause_time_ms += predicted_time_ms;
ysr@777 3109 add_to_collection_set(hr);
ysr@777 3110 record_cset_region(hr, false);
ysr@777 3111 max_live_bytes -= MIN2(hr->max_live_bytes(), max_live_bytes);
ysr@777 3112 if (G1PolicyVerbose > 0) {
ysr@777 3113 gclog_or_tty->print_cr(" (" SIZE_FORMAT " KB left in heap.)",
ysr@777 3114 max_live_bytes/K);
ysr@777 3115 }
ysr@777 3116 seq.add(predicted_time_ms);
ysr@777 3117 avg_prediction = seq.avg() + seq.sd();
ysr@777 3118 }
ysr@777 3119 should_continue =
ysr@777 3120 ( hr != NULL) &&
ysr@777 3121 ( (adaptive_young_list_length()) ? time_remaining_ms > 0.0
ysr@777 3122 : _collection_set_size < _young_list_fixed_length );
ysr@777 3123 } while (should_continue);
ysr@777 3124
ysr@777 3125 if (!adaptive_young_list_length() &&
ysr@777 3126 _collection_set_size < _young_list_fixed_length)
ysr@777 3127 _should_revert_to_full_young_gcs = true;
ysr@777 3128 }
ysr@777 3129
ysr@777 3130 choose_collection_set_end:
ysr@777 3131 count_CS_bytes_used();
ysr@777 3132
ysr@777 3133 end_recording_regions();
ysr@777 3134
ysr@777 3135 double non_young_end_time_sec = os::elapsedTime();
ysr@777 3136 _recorded_non_young_cset_choice_time_ms =
ysr@777 3137 (non_young_end_time_sec - non_young_start_time_sec) * 1000.0;
ysr@777 3138 }
ysr@777 3139
ysr@777 3140 void G1CollectorPolicy_BestRegionsFirst::record_full_collection_end() {
ysr@777 3141 G1CollectorPolicy::record_full_collection_end();
ysr@777 3142 _collectionSetChooser->updateAfterFullCollection();
ysr@777 3143 }
ysr@777 3144
ysr@777 3145 void G1CollectorPolicy_BestRegionsFirst::
ysr@777 3146 expand_if_possible(size_t numRegions) {
ysr@777 3147 size_t expansion_bytes = numRegions * HeapRegion::GrainBytes;
ysr@777 3148 _g1->expand(expansion_bytes);
ysr@777 3149 }
ysr@777 3150
ysr@777 3151 void G1CollectorPolicy_BestRegionsFirst::
ysr@777 3152 record_collection_pause_end(bool popular, bool abandoned) {
ysr@777 3153 G1CollectorPolicy::record_collection_pause_end(popular, abandoned);
ysr@777 3154 assert(assertMarkedBytesDataOK(), "Marked regions not OK at pause end.");
ysr@777 3155 }
ysr@777 3156
ysr@777 3157 // Local Variables: ***
ysr@777 3158 // c-indentation-style: gnu ***
ysr@777 3159 // End: ***

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