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

Fri, 16 Apr 2010 08:48:16 -0700

author
apetrusenko
date
Fri, 16 Apr 2010 08:48:16 -0700
changeset 1826
79e419e5ea3b
parent 1823
7666957bc44d
child 1829
1316cec51b4d
permissions
-rw-r--r--

6942253: G1: replace G1ParallelGCAllocBufferSize with YoungPLABSize and OldPLABSize
Summary: Replaces the G1-specific parameter with the existing ones that are used by the other GCs (YoungPLABSize and OldPLABSize)
Reviewed-by: tonyp, johnc

ysr@777 1 /*
xdono@1014 2 * Copyright 2001-2009 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
apetrusenko@1112 94 _summary(new Summary()),
apetrusenko@1112 95 _abandoned_summary(new AbandonedSummary()),
ysr@777 96
johnc@1325 97 #ifndef PRODUCT
ysr@777 98 _cur_clear_ct_time_ms(0.0),
johnc@1325 99 _min_clear_cc_time_ms(-1.0),
johnc@1325 100 _max_clear_cc_time_ms(-1.0),
johnc@1325 101 _cur_clear_cc_time_ms(0.0),
johnc@1325 102 _cum_clear_cc_time_ms(0.0),
johnc@1325 103 _num_cc_clears(0L),
johnc@1325 104 #endif
ysr@777 105
ysr@777 106 _region_num_young(0),
ysr@777 107 _region_num_tenured(0),
ysr@777 108 _prev_region_num_young(0),
ysr@777 109 _prev_region_num_tenured(0),
ysr@777 110
ysr@777 111 _aux_num(10),
ysr@777 112 _all_aux_times_ms(new NumberSeq[_aux_num]),
ysr@777 113 _cur_aux_start_times_ms(new double[_aux_num]),
ysr@777 114 _cur_aux_times_ms(new double[_aux_num]),
ysr@777 115 _cur_aux_times_set(new bool[_aux_num]),
ysr@777 116
ysr@777 117 _concurrent_mark_init_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 118 _concurrent_mark_remark_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 119 _concurrent_mark_cleanup_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 120
ysr@777 121 // <NEW PREDICTION>
ysr@777 122
ysr@777 123 _alloc_rate_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 124 _prev_collection_pause_end_ms(0.0),
ysr@777 125 _pending_card_diff_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 126 _rs_length_diff_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 127 _cost_per_card_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 128 _cost_per_scan_only_region_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 129 _fully_young_cards_per_entry_ratio_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 130 _partially_young_cards_per_entry_ratio_seq(
ysr@777 131 new TruncatedSeq(TruncatedSeqLength)),
ysr@777 132 _cost_per_entry_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 133 _partially_young_cost_per_entry_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 134 _cost_per_byte_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 135 _cost_per_byte_ms_during_cm_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 136 _cost_per_scan_only_region_ms_during_cm_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 137 _constant_other_time_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 138 _young_other_cost_per_region_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 139 _non_young_other_cost_per_region_ms_seq(
ysr@777 140 new TruncatedSeq(TruncatedSeqLength)),
ysr@777 141
ysr@777 142 _pending_cards_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 143 _scanned_cards_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 144 _rs_lengths_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 145
johnc@1186 146 _pause_time_target_ms((double) MaxGCPauseMillis),
ysr@777 147
ysr@777 148 // </NEW PREDICTION>
ysr@777 149
ysr@777 150 _in_young_gc_mode(false),
ysr@777 151 _full_young_gcs(true),
ysr@777 152 _full_young_pause_num(0),
ysr@777 153 _partial_young_pause_num(0),
ysr@777 154
ysr@777 155 _during_marking(false),
ysr@777 156 _in_marking_window(false),
ysr@777 157 _in_marking_window_im(false),
ysr@777 158
ysr@777 159 _known_garbage_ratio(0.0),
ysr@777 160 _known_garbage_bytes(0),
ysr@777 161
ysr@777 162 _young_gc_eff_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 163 _target_pause_time_ms(-1.0),
ysr@777 164
ysr@777 165 _recent_prev_end_times_for_all_gcs_sec(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 166
ysr@777 167 _recent_CS_bytes_used_before(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 168 _recent_CS_bytes_surviving(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 169
ysr@777 170 _recent_avg_pause_time_ratio(0.0),
ysr@777 171 _num_markings(0),
ysr@777 172 _n_marks(0),
ysr@777 173 _n_pauses_at_mark_end(0),
ysr@777 174
ysr@777 175 _all_full_gc_times_ms(new NumberSeq()),
ysr@777 176
ysr@777 177 // G1PausesBtwnConcMark defaults to -1
ysr@777 178 // so the hack is to do the cast QQQ FIXME
ysr@777 179 _pauses_btwn_concurrent_mark((size_t)G1PausesBtwnConcMark),
ysr@777 180 _n_marks_since_last_pause(0),
tonyp@1794 181 _initiate_conc_mark_if_possible(false),
tonyp@1794 182 _during_initial_mark_pause(false),
ysr@777 183 _should_revert_to_full_young_gcs(false),
ysr@777 184 _last_full_young_gc(false),
ysr@777 185
ysr@777 186 _prev_collection_pause_used_at_end_bytes(0),
ysr@777 187
ysr@777 188 _collection_set(NULL),
ysr@777 189 #ifdef _MSC_VER // the use of 'this' below gets a warning, make it go away
ysr@777 190 #pragma warning( disable:4355 ) // 'this' : used in base member initializer list
ysr@777 191 #endif // _MSC_VER
ysr@777 192
ysr@777 193 _short_lived_surv_rate_group(new SurvRateGroup(this, "Short Lived",
ysr@777 194 G1YoungSurvRateNumRegionsSummary)),
ysr@777 195 _survivor_surv_rate_group(new SurvRateGroup(this, "Survivor",
apetrusenko@980 196 G1YoungSurvRateNumRegionsSummary)),
ysr@777 197 // add here any more surv rate groups
apetrusenko@980 198 _recorded_survivor_regions(0),
apetrusenko@980 199 _recorded_survivor_head(NULL),
apetrusenko@980 200 _recorded_survivor_tail(NULL),
tonyp@1791 201 _survivors_age_table(true),
tonyp@1791 202
tonyp@1791 203 _gc_overhead_perc(0.0)
apetrusenko@980 204
ysr@777 205 {
tonyp@1377 206 // Set up the region size and associated fields. Given that the
tonyp@1377 207 // policy is created before the heap, we have to set this up here,
tonyp@1377 208 // so it's done as soon as possible.
tonyp@1377 209 HeapRegion::setup_heap_region_size(Arguments::min_heap_size());
iveresov@1696 210 HeapRegionRemSet::setup_remset_size();
tonyp@1377 211
apetrusenko@1826 212 // Verify PLAB sizes
apetrusenko@1826 213 const uint region_size = HeapRegion::GrainWords;
apetrusenko@1826 214 if (YoungPLABSize > region_size || OldPLABSize > region_size) {
apetrusenko@1826 215 char buffer[128];
apetrusenko@1826 216 jio_snprintf(buffer, sizeof(buffer), "%sPLABSize should be at most %u",
apetrusenko@1826 217 OldPLABSize > region_size ? "Old" : "Young", region_size);
apetrusenko@1826 218 vm_exit_during_initialization(buffer);
apetrusenko@1826 219 }
apetrusenko@1826 220
ysr@777 221 _recent_prev_end_times_for_all_gcs_sec->add(os::elapsedTime());
ysr@777 222 _prev_collection_pause_end_ms = os::elapsedTime() * 1000.0;
ysr@777 223
ysr@777 224 _par_last_ext_root_scan_times_ms = new double[_parallel_gc_threads];
ysr@777 225 _par_last_mark_stack_scan_times_ms = new double[_parallel_gc_threads];
ysr@777 226 _par_last_scan_only_times_ms = new double[_parallel_gc_threads];
ysr@777 227 _par_last_scan_only_regions_scanned = new double[_parallel_gc_threads];
ysr@777 228
ysr@777 229 _par_last_update_rs_start_times_ms = new double[_parallel_gc_threads];
ysr@777 230 _par_last_update_rs_times_ms = new double[_parallel_gc_threads];
ysr@777 231 _par_last_update_rs_processed_buffers = new double[_parallel_gc_threads];
ysr@777 232
ysr@777 233 _par_last_scan_rs_start_times_ms = new double[_parallel_gc_threads];
ysr@777 234 _par_last_scan_rs_times_ms = new double[_parallel_gc_threads];
ysr@777 235 _par_last_scan_new_refs_times_ms = new double[_parallel_gc_threads];
ysr@777 236
ysr@777 237 _par_last_obj_copy_times_ms = new double[_parallel_gc_threads];
ysr@777 238
ysr@777 239 _par_last_termination_times_ms = new double[_parallel_gc_threads];
ysr@777 240
ysr@777 241 // start conservatively
johnc@1186 242 _expensive_region_limit_ms = 0.5 * (double) MaxGCPauseMillis;
ysr@777 243
ysr@777 244 // <NEW PREDICTION>
ysr@777 245
ysr@777 246 int index;
ysr@777 247 if (ParallelGCThreads == 0)
ysr@777 248 index = 0;
ysr@777 249 else if (ParallelGCThreads > 8)
ysr@777 250 index = 7;
ysr@777 251 else
ysr@777 252 index = ParallelGCThreads - 1;
ysr@777 253
ysr@777 254 _pending_card_diff_seq->add(0.0);
ysr@777 255 _rs_length_diff_seq->add(rs_length_diff_defaults[index]);
ysr@777 256 _cost_per_card_ms_seq->add(cost_per_card_ms_defaults[index]);
ysr@777 257 _cost_per_scan_only_region_ms_seq->add(
ysr@777 258 cost_per_scan_only_region_ms_defaults[index]);
ysr@777 259 _fully_young_cards_per_entry_ratio_seq->add(
ysr@777 260 fully_young_cards_per_entry_ratio_defaults[index]);
ysr@777 261 _cost_per_entry_ms_seq->add(cost_per_entry_ms_defaults[index]);
ysr@777 262 _cost_per_byte_ms_seq->add(cost_per_byte_ms_defaults[index]);
ysr@777 263 _constant_other_time_ms_seq->add(constant_other_time_ms_defaults[index]);
ysr@777 264 _young_other_cost_per_region_ms_seq->add(
ysr@777 265 young_other_cost_per_region_ms_defaults[index]);
ysr@777 266 _non_young_other_cost_per_region_ms_seq->add(
ysr@777 267 non_young_other_cost_per_region_ms_defaults[index]);
ysr@777 268
ysr@777 269 // </NEW PREDICTION>
ysr@777 270
johnc@1186 271 double time_slice = (double) GCPauseIntervalMillis / 1000.0;
johnc@1186 272 double max_gc_time = (double) MaxGCPauseMillis / 1000.0;
ysr@777 273 guarantee(max_gc_time < time_slice,
ysr@777 274 "Max GC time should not be greater than the time slice");
ysr@777 275 _mmu_tracker = new G1MMUTrackerQueue(time_slice, max_gc_time);
johnc@1186 276 _sigma = (double) G1ConfidencePercent / 100.0;
ysr@777 277
ysr@777 278 // start conservatively (around 50ms is about right)
ysr@777 279 _concurrent_mark_init_times_ms->add(0.05);
ysr@777 280 _concurrent_mark_remark_times_ms->add(0.05);
ysr@777 281 _concurrent_mark_cleanup_times_ms->add(0.20);
ysr@777 282 _tenuring_threshold = MaxTenuringThreshold;
ysr@777 283
tonyp@1717 284 // if G1FixedSurvivorSpaceSize is 0 which means the size is not
tonyp@1717 285 // fixed, then _max_survivor_regions will be calculated at
tonyp@1717 286 // calculate_young_list_target_config during initialization
tonyp@1717 287 _max_survivor_regions = G1FixedSurvivorSpaceSize / HeapRegion::GrainBytes;
apetrusenko@980 288
tonyp@1791 289 assert(GCTimeRatio > 0,
tonyp@1791 290 "we should have set it to a default value set_g1_gc_flags() "
tonyp@1791 291 "if a user set it to 0");
tonyp@1791 292 _gc_overhead_perc = 100.0 * (1.0 / (1.0 + GCTimeRatio));
tonyp@1791 293
ysr@777 294 initialize_all();
ysr@777 295 }
ysr@777 296
ysr@777 297 // Increment "i", mod "len"
ysr@777 298 static void inc_mod(int& i, int len) {
ysr@777 299 i++; if (i == len) i = 0;
ysr@777 300 }
ysr@777 301
ysr@777 302 void G1CollectorPolicy::initialize_flags() {
ysr@777 303 set_min_alignment(HeapRegion::GrainBytes);
ysr@777 304 set_max_alignment(GenRemSet::max_alignment_constraint(rem_set_name()));
apetrusenko@982 305 if (SurvivorRatio < 1) {
apetrusenko@982 306 vm_exit_during_initialization("Invalid survivor ratio specified");
apetrusenko@982 307 }
ysr@777 308 CollectorPolicy::initialize_flags();
ysr@777 309 }
ysr@777 310
tonyp@1720 311 // The easiest way to deal with the parsing of the NewSize /
tonyp@1720 312 // MaxNewSize / etc. parameteres is to re-use the code in the
tonyp@1720 313 // TwoGenerationCollectorPolicy class. This is similar to what
tonyp@1720 314 // ParallelScavenge does with its GenerationSizer class (see
tonyp@1720 315 // ParallelScavengeHeap::initialize()). We might change this in the
tonyp@1720 316 // future, but it's a good start.
tonyp@1720 317 class G1YoungGenSizer : public TwoGenerationCollectorPolicy {
tonyp@1720 318 size_t size_to_region_num(size_t byte_size) {
tonyp@1720 319 return MAX2((size_t) 1, byte_size / HeapRegion::GrainBytes);
tonyp@1720 320 }
tonyp@1720 321
tonyp@1720 322 public:
tonyp@1720 323 G1YoungGenSizer() {
tonyp@1720 324 initialize_flags();
tonyp@1720 325 initialize_size_info();
tonyp@1720 326 }
tonyp@1720 327
tonyp@1720 328 size_t min_young_region_num() {
tonyp@1720 329 return size_to_region_num(_min_gen0_size);
tonyp@1720 330 }
tonyp@1720 331 size_t initial_young_region_num() {
tonyp@1720 332 return size_to_region_num(_initial_gen0_size);
tonyp@1720 333 }
tonyp@1720 334 size_t max_young_region_num() {
tonyp@1720 335 return size_to_region_num(_max_gen0_size);
tonyp@1720 336 }
tonyp@1720 337 };
tonyp@1720 338
ysr@777 339 void G1CollectorPolicy::init() {
ysr@777 340 // Set aside an initial future to_space.
ysr@777 341 _g1 = G1CollectedHeap::heap();
ysr@777 342
ysr@777 343 assert(Heap_lock->owned_by_self(), "Locking discipline.");
ysr@777 344
apetrusenko@980 345 initialize_gc_policy_counters();
apetrusenko@980 346
ysr@777 347 if (G1Gen) {
ysr@777 348 _in_young_gc_mode = true;
ysr@777 349
tonyp@1720 350 G1YoungGenSizer sizer;
tonyp@1720 351 size_t initial_region_num = sizer.initial_young_region_num();
tonyp@1720 352
tonyp@1720 353 if (UseAdaptiveSizePolicy) {
ysr@777 354 set_adaptive_young_list_length(true);
ysr@777 355 _young_list_fixed_length = 0;
ysr@777 356 } else {
ysr@777 357 set_adaptive_young_list_length(false);
tonyp@1720 358 _young_list_fixed_length = initial_region_num;
ysr@777 359 }
ysr@777 360 _free_regions_at_end_of_collection = _g1->free_regions();
ysr@777 361 _scan_only_regions_at_end_of_collection = 0;
ysr@777 362 calculate_young_list_min_length();
ysr@777 363 guarantee( _young_list_min_length == 0, "invariant, not enough info" );
ysr@777 364 calculate_young_list_target_config();
ysr@777 365 } else {
ysr@777 366 _young_list_fixed_length = 0;
ysr@777 367 _in_young_gc_mode = false;
ysr@777 368 }
ysr@777 369 }
ysr@777 370
apetrusenko@980 371 // Create the jstat counters for the policy.
apetrusenko@980 372 void G1CollectorPolicy::initialize_gc_policy_counters()
apetrusenko@980 373 {
apetrusenko@980 374 _gc_policy_counters = new GCPolicyCounters("GarbageFirst", 1, 2 + G1Gen);
apetrusenko@980 375 }
apetrusenko@980 376
ysr@777 377 void G1CollectorPolicy::calculate_young_list_min_length() {
ysr@777 378 _young_list_min_length = 0;
ysr@777 379
ysr@777 380 if (!adaptive_young_list_length())
ysr@777 381 return;
ysr@777 382
ysr@777 383 if (_alloc_rate_ms_seq->num() > 3) {
ysr@777 384 double now_sec = os::elapsedTime();
ysr@777 385 double when_ms = _mmu_tracker->when_max_gc_sec(now_sec) * 1000.0;
ysr@777 386 double alloc_rate_ms = predict_alloc_rate_ms();
ysr@777 387 int min_regions = (int) ceil(alloc_rate_ms * when_ms);
ysr@777 388 int current_region_num = (int) _g1->young_list_length();
ysr@777 389 _young_list_min_length = min_regions + current_region_num;
ysr@777 390 }
ysr@777 391 }
ysr@777 392
ysr@777 393 void G1CollectorPolicy::calculate_young_list_target_config() {
ysr@777 394 if (adaptive_young_list_length()) {
ysr@777 395 size_t rs_lengths = (size_t) get_new_prediction(_rs_lengths_seq);
ysr@777 396 calculate_young_list_target_config(rs_lengths);
ysr@777 397 } else {
ysr@777 398 if (full_young_gcs())
ysr@777 399 _young_list_target_length = _young_list_fixed_length;
ysr@777 400 else
ysr@777 401 _young_list_target_length = _young_list_fixed_length / 2;
ysr@777 402 _young_list_target_length = MAX2(_young_list_target_length, (size_t)1);
ysr@777 403 size_t so_length = calculate_optimal_so_length(_young_list_target_length);
ysr@777 404 guarantee( so_length < _young_list_target_length, "invariant" );
ysr@777 405 _young_list_so_prefix_length = so_length;
ysr@777 406 }
apetrusenko@980 407 calculate_survivors_policy();
ysr@777 408 }
ysr@777 409
ysr@777 410 // This method calculate the optimal scan-only set for a fixed young
ysr@777 411 // gen size. I couldn't work out how to reuse the more elaborate one,
ysr@777 412 // i.e. calculate_young_list_target_config(rs_length), as the loops are
ysr@777 413 // fundamentally different (the other one finds a config for different
ysr@777 414 // S-O lengths, whereas here we need to do the opposite).
ysr@777 415 size_t G1CollectorPolicy::calculate_optimal_so_length(
ysr@777 416 size_t young_list_length) {
ysr@777 417 if (!G1UseScanOnlyPrefix)
ysr@777 418 return 0;
ysr@777 419
ysr@777 420 if (_all_pause_times_ms->num() < 3) {
ysr@777 421 // we won't use a scan-only set at the beginning to allow the rest
ysr@777 422 // of the predictors to warm up
ysr@777 423 return 0;
ysr@777 424 }
ysr@777 425
ysr@777 426 if (_cost_per_scan_only_region_ms_seq->num() < 3) {
ysr@777 427 // then, we'll only set the S-O set to 1 for a little bit of time,
ysr@777 428 // to get enough information on the scanning cost
ysr@777 429 return 1;
ysr@777 430 }
ysr@777 431
ysr@777 432 size_t pending_cards = (size_t) get_new_prediction(_pending_cards_seq);
ysr@777 433 size_t rs_lengths = (size_t) get_new_prediction(_rs_lengths_seq);
ysr@777 434 size_t adj_rs_lengths = rs_lengths + predict_rs_length_diff();
ysr@777 435 size_t scanned_cards;
ysr@777 436 if (full_young_gcs())
ysr@777 437 scanned_cards = predict_young_card_num(adj_rs_lengths);
ysr@777 438 else
ysr@777 439 scanned_cards = predict_non_young_card_num(adj_rs_lengths);
ysr@777 440 double base_time_ms = predict_base_elapsed_time_ms(pending_cards,
ysr@777 441 scanned_cards);
ysr@777 442
ysr@777 443 size_t so_length = 0;
ysr@777 444 double max_gc_eff = 0.0;
ysr@777 445 for (size_t i = 0; i < young_list_length; ++i) {
ysr@777 446 double gc_eff = 0.0;
ysr@777 447 double pause_time_ms = 0.0;
ysr@777 448 predict_gc_eff(young_list_length, i, base_time_ms,
ysr@777 449 &gc_eff, &pause_time_ms);
ysr@777 450 if (gc_eff > max_gc_eff) {
ysr@777 451 max_gc_eff = gc_eff;
ysr@777 452 so_length = i;
ysr@777 453 }
ysr@777 454 }
ysr@777 455
ysr@777 456 // set it to 95% of the optimal to make sure we sample the "area"
ysr@777 457 // around the optimal length to get up-to-date survival rate data
ysr@777 458 return so_length * 950 / 1000;
ysr@777 459 }
ysr@777 460
ysr@777 461 // This is a really cool piece of code! It finds the best
ysr@777 462 // target configuration (young length / scan-only prefix length) so
ysr@777 463 // that GC efficiency is maximized and that we also meet a pause
ysr@777 464 // time. It's a triple nested loop. These loops are explained below
ysr@777 465 // from the inside-out :-)
ysr@777 466 //
ysr@777 467 // (a) The innermost loop will try to find the optimal young length
ysr@777 468 // for a fixed S-O length. It uses a binary search to speed up the
ysr@777 469 // process. We assume that, for a fixed S-O length, as we add more
ysr@777 470 // young regions to the CSet, the GC efficiency will only go up (I'll
ysr@777 471 // skip the proof). So, using a binary search to optimize this process
ysr@777 472 // makes perfect sense.
ysr@777 473 //
ysr@777 474 // (b) The middle loop will fix the S-O length before calling the
ysr@777 475 // innermost one. It will vary it between two parameters, increasing
ysr@777 476 // it by a given increment.
ysr@777 477 //
ysr@777 478 // (c) The outermost loop will call the middle loop three times.
ysr@777 479 // (1) The first time it will explore all possible S-O length values
ysr@777 480 // from 0 to as large as it can get, using a coarse increment (to
ysr@777 481 // quickly "home in" to where the optimal seems to be).
ysr@777 482 // (2) The second time it will explore the values around the optimal
ysr@777 483 // that was found by the first iteration using a fine increment.
ysr@777 484 // (3) Once the optimal config has been determined by the second
ysr@777 485 // iteration, we'll redo the calculation, but setting the S-O length
ysr@777 486 // to 95% of the optimal to make sure we sample the "area"
ysr@777 487 // around the optimal length to get up-to-date survival rate data
ysr@777 488 //
ysr@777 489 // Termination conditions for the iterations are several: the pause
ysr@777 490 // time is over the limit, we do not have enough to-space, etc.
ysr@777 491
ysr@777 492 void G1CollectorPolicy::calculate_young_list_target_config(size_t rs_lengths) {
ysr@777 493 guarantee( adaptive_young_list_length(), "pre-condition" );
ysr@777 494
ysr@777 495 double start_time_sec = os::elapsedTime();
tonyp@1717 496 size_t min_reserve_perc = MAX2((size_t)2, (size_t)G1ReservePercent);
ysr@777 497 min_reserve_perc = MIN2((size_t) 50, min_reserve_perc);
ysr@777 498 size_t reserve_regions =
ysr@777 499 (size_t) ((double) min_reserve_perc * (double) _g1->n_regions() / 100.0);
ysr@777 500
ysr@777 501 if (full_young_gcs() && _free_regions_at_end_of_collection > 0) {
ysr@777 502 // we are in fully-young mode and there are free regions in the heap
ysr@777 503
apetrusenko@980 504 double survivor_regions_evac_time =
apetrusenko@980 505 predict_survivor_regions_evac_time();
apetrusenko@980 506
ysr@777 507 size_t min_so_length = 0;
ysr@777 508 size_t max_so_length = 0;
ysr@777 509
ysr@777 510 if (G1UseScanOnlyPrefix) {
ysr@777 511 if (_all_pause_times_ms->num() < 3) {
ysr@777 512 // we won't use a scan-only set at the beginning to allow the rest
ysr@777 513 // of the predictors to warm up
ysr@777 514 min_so_length = 0;
ysr@777 515 max_so_length = 0;
ysr@777 516 } else if (_cost_per_scan_only_region_ms_seq->num() < 3) {
ysr@777 517 // then, we'll only set the S-O set to 1 for a little bit of time,
ysr@777 518 // to get enough information on the scanning cost
ysr@777 519 min_so_length = 1;
ysr@777 520 max_so_length = 1;
ysr@777 521 } else if (_in_marking_window || _last_full_young_gc) {
ysr@777 522 // no S-O prefix during a marking phase either, as at the end
ysr@777 523 // of the marking phase we'll have to use a very small young
ysr@777 524 // length target to fill up the rest of the CSet with
ysr@777 525 // non-young regions and, if we have lots of scan-only regions
ysr@777 526 // left-over, we will not be able to add any more non-young
ysr@777 527 // regions.
ysr@777 528 min_so_length = 0;
ysr@777 529 max_so_length = 0;
ysr@777 530 } else {
ysr@777 531 // this is the common case; we'll never reach the maximum, we
ysr@777 532 // one of the end conditions will fire well before that
ysr@777 533 // (hopefully!)
ysr@777 534 min_so_length = 0;
ysr@777 535 max_so_length = _free_regions_at_end_of_collection - 1;
ysr@777 536 }
ysr@777 537 } else {
ysr@777 538 // no S-O prefix, as the switch is not set, but we still need to
ysr@777 539 // do one iteration to calculate the best young target that
ysr@777 540 // meets the pause time; this way we reuse the same code instead
ysr@777 541 // of replicating it
ysr@777 542 min_so_length = 0;
ysr@777 543 max_so_length = 0;
ysr@777 544 }
ysr@777 545
ysr@777 546 double target_pause_time_ms = _mmu_tracker->max_gc_time() * 1000.0;
ysr@777 547 size_t pending_cards = (size_t) get_new_prediction(_pending_cards_seq);
ysr@777 548 size_t adj_rs_lengths = rs_lengths + predict_rs_length_diff();
ysr@777 549 size_t scanned_cards;
ysr@777 550 if (full_young_gcs())
ysr@777 551 scanned_cards = predict_young_card_num(adj_rs_lengths);
ysr@777 552 else
ysr@777 553 scanned_cards = predict_non_young_card_num(adj_rs_lengths);
ysr@777 554 // calculate this once, so that we don't have to recalculate it in
ysr@777 555 // the innermost loop
apetrusenko@980 556 double base_time_ms = predict_base_elapsed_time_ms(pending_cards, scanned_cards)
apetrusenko@980 557 + survivor_regions_evac_time;
ysr@777 558 // the result
ysr@777 559 size_t final_young_length = 0;
ysr@777 560 size_t final_so_length = 0;
ysr@777 561 double final_gc_eff = 0.0;
ysr@777 562 // we'll also keep track of how many times we go into the inner loop
ysr@777 563 // this is for profiling reasons
ysr@777 564 size_t calculations = 0;
ysr@777 565
ysr@777 566 // this determines which of the three iterations the outer loop is in
ysr@777 567 typedef enum {
ysr@777 568 pass_type_coarse,
ysr@777 569 pass_type_fine,
ysr@777 570 pass_type_final
ysr@777 571 } pass_type_t;
ysr@777 572
ysr@777 573 // range of the outer loop's iteration
ysr@777 574 size_t from_so_length = min_so_length;
ysr@777 575 size_t to_so_length = max_so_length;
ysr@777 576 guarantee( from_so_length <= to_so_length, "invariant" );
ysr@777 577
ysr@777 578 // this will keep the S-O length that's found by the second
ysr@777 579 // iteration of the outer loop; we'll keep it just in case the third
ysr@777 580 // iteration fails to find something
ysr@777 581 size_t fine_so_length = 0;
ysr@777 582
ysr@777 583 // the increment step for the coarse (first) iteration
ysr@777 584 size_t so_coarse_increments = 5;
ysr@777 585
ysr@777 586 // the common case, we'll start with the coarse iteration
ysr@777 587 pass_type_t pass = pass_type_coarse;
ysr@777 588 size_t so_length_incr = so_coarse_increments;
ysr@777 589
ysr@777 590 if (from_so_length == to_so_length) {
ysr@777 591 // not point in doing the coarse iteration, we'll go directly into
ysr@777 592 // the fine one (we essentially trying to find the optimal young
ysr@777 593 // length for a fixed S-O length).
ysr@777 594 so_length_incr = 1;
ysr@777 595 pass = pass_type_final;
ysr@777 596 } else if (to_so_length - from_so_length < 3 * so_coarse_increments) {
ysr@777 597 // again, the range is too short so no point in foind the coarse
ysr@777 598 // iteration either
ysr@777 599 so_length_incr = 1;
ysr@777 600 pass = pass_type_fine;
ysr@777 601 }
ysr@777 602
ysr@777 603 bool done = false;
ysr@777 604 // this is the outermost loop
ysr@777 605 while (!done) {
apetrusenko@980 606 #ifdef TRACE_CALC_YOUNG_CONFIG
ysr@777 607 // leave this in for debugging, just in case
ysr@777 608 gclog_or_tty->print_cr("searching between " SIZE_FORMAT " and " SIZE_FORMAT
ysr@777 609 ", incr " SIZE_FORMAT ", pass %s",
ysr@777 610 from_so_length, to_so_length, so_length_incr,
ysr@777 611 (pass == pass_type_coarse) ? "coarse" :
ysr@777 612 (pass == pass_type_fine) ? "fine" : "final");
apetrusenko@980 613 #endif // TRACE_CALC_YOUNG_CONFIG
ysr@777 614
ysr@777 615 size_t so_length = from_so_length;
ysr@777 616 size_t init_free_regions =
ysr@777 617 MAX2((size_t)0,
ysr@777 618 _free_regions_at_end_of_collection +
ysr@777 619 _scan_only_regions_at_end_of_collection - reserve_regions);
ysr@777 620
ysr@777 621 // this determines whether a configuration was found
ysr@777 622 bool gc_eff_set = false;
ysr@777 623 // this is the middle loop
ysr@777 624 while (so_length <= to_so_length) {
ysr@777 625 // base time, which excludes region-related time; again we
ysr@777 626 // calculate it once to avoid recalculating it in the
ysr@777 627 // innermost loop
ysr@777 628 double base_time_with_so_ms =
ysr@777 629 base_time_ms + predict_scan_only_time_ms(so_length);
ysr@777 630 // it's already over the pause target, go around
ysr@777 631 if (base_time_with_so_ms > target_pause_time_ms)
ysr@777 632 break;
ysr@777 633
ysr@777 634 size_t starting_young_length = so_length+1;
ysr@777 635
ysr@777 636 // we make sure that the short young length that makes sense
ysr@777 637 // (one more than the S-O length) is feasible
ysr@777 638 size_t min_young_length = starting_young_length;
ysr@777 639 double min_gc_eff;
ysr@777 640 bool min_ok;
ysr@777 641 ++calculations;
ysr@777 642 min_ok = predict_gc_eff(min_young_length, so_length,
ysr@777 643 base_time_with_so_ms,
ysr@777 644 init_free_regions, target_pause_time_ms,
ysr@777 645 &min_gc_eff);
ysr@777 646
ysr@777 647 if (min_ok) {
ysr@777 648 // the shortest young length is indeed feasible; we'll know
ysr@777 649 // set up the max young length and we'll do a binary search
ysr@777 650 // between min_young_length and max_young_length
ysr@777 651 size_t max_young_length = _free_regions_at_end_of_collection - 1;
ysr@777 652 double max_gc_eff = 0.0;
ysr@777 653 bool max_ok = false;
ysr@777 654
ysr@777 655 // the innermost loop! (finally!)
ysr@777 656 while (max_young_length > min_young_length) {
ysr@777 657 // we'll make sure that min_young_length is always at a
ysr@777 658 // feasible config
ysr@777 659 guarantee( min_ok, "invariant" );
ysr@777 660
ysr@777 661 ++calculations;
ysr@777 662 max_ok = predict_gc_eff(max_young_length, so_length,
ysr@777 663 base_time_with_so_ms,
ysr@777 664 init_free_regions, target_pause_time_ms,
ysr@777 665 &max_gc_eff);
ysr@777 666
ysr@777 667 size_t diff = (max_young_length - min_young_length) / 2;
ysr@777 668 if (max_ok) {
ysr@777 669 min_young_length = max_young_length;
ysr@777 670 min_gc_eff = max_gc_eff;
ysr@777 671 min_ok = true;
ysr@777 672 }
ysr@777 673 max_young_length = min_young_length + diff;
ysr@777 674 }
ysr@777 675
ysr@777 676 // the innermost loop found a config
ysr@777 677 guarantee( min_ok, "invariant" );
ysr@777 678 if (min_gc_eff > final_gc_eff) {
ysr@777 679 // it's the best config so far, so we'll keep it
ysr@777 680 final_gc_eff = min_gc_eff;
ysr@777 681 final_young_length = min_young_length;
ysr@777 682 final_so_length = so_length;
ysr@777 683 gc_eff_set = true;
ysr@777 684 }
ysr@777 685 }
ysr@777 686
ysr@777 687 // incremental the fixed S-O length and go around
ysr@777 688 so_length += so_length_incr;
ysr@777 689 }
ysr@777 690
ysr@777 691 // this is the end of the outermost loop and we need to decide
ysr@777 692 // what to do during the next iteration
ysr@777 693 if (pass == pass_type_coarse) {
ysr@777 694 // we just did the coarse pass (first iteration)
ysr@777 695
ysr@777 696 if (!gc_eff_set)
ysr@777 697 // we didn't find a feasible config so we'll just bail out; of
ysr@777 698 // course, it might be the case that we missed it; but I'd say
ysr@777 699 // it's a bit unlikely
ysr@777 700 done = true;
ysr@777 701 else {
ysr@777 702 // We did find a feasible config with optimal GC eff during
ysr@777 703 // the first pass. So the second pass we'll only consider the
ysr@777 704 // S-O lengths around that config with a fine increment.
ysr@777 705
ysr@777 706 guarantee( so_length_incr == so_coarse_increments, "invariant" );
ysr@777 707 guarantee( final_so_length >= min_so_length, "invariant" );
ysr@777 708
apetrusenko@980 709 #ifdef TRACE_CALC_YOUNG_CONFIG
ysr@777 710 // leave this in for debugging, just in case
ysr@777 711 gclog_or_tty->print_cr(" coarse pass: SO length " SIZE_FORMAT,
ysr@777 712 final_so_length);
apetrusenko@980 713 #endif // TRACE_CALC_YOUNG_CONFIG
ysr@777 714
ysr@777 715 from_so_length =
ysr@777 716 (final_so_length - min_so_length > so_coarse_increments) ?
ysr@777 717 final_so_length - so_coarse_increments + 1 : min_so_length;
ysr@777 718 to_so_length =
ysr@777 719 (max_so_length - final_so_length > so_coarse_increments) ?
ysr@777 720 final_so_length + so_coarse_increments - 1 : max_so_length;
ysr@777 721
ysr@777 722 pass = pass_type_fine;
ysr@777 723 so_length_incr = 1;
ysr@777 724 }
ysr@777 725 } else if (pass == pass_type_fine) {
ysr@777 726 // we just finished the second pass
ysr@777 727
ysr@777 728 if (!gc_eff_set) {
ysr@777 729 // we didn't find a feasible config (yes, it's possible;
ysr@777 730 // notice that, sometimes, we go directly into the fine
ysr@777 731 // iteration and skip the coarse one) so we bail out
ysr@777 732 done = true;
ysr@777 733 } else {
ysr@777 734 // We did find a feasible config with optimal GC eff
ysr@777 735 guarantee( so_length_incr == 1, "invariant" );
ysr@777 736
ysr@777 737 if (final_so_length == 0) {
ysr@777 738 // The config is of an empty S-O set, so we'll just bail out
ysr@777 739 done = true;
ysr@777 740 } else {
ysr@777 741 // we'll go around once more, setting the S-O length to 95%
ysr@777 742 // of the optimal
ysr@777 743 size_t new_so_length = 950 * final_so_length / 1000;
ysr@777 744
apetrusenko@980 745 #ifdef TRACE_CALC_YOUNG_CONFIG
ysr@777 746 // leave this in for debugging, just in case
ysr@777 747 gclog_or_tty->print_cr(" fine pass: SO length " SIZE_FORMAT
ysr@777 748 ", setting it to " SIZE_FORMAT,
ysr@777 749 final_so_length, new_so_length);
apetrusenko@980 750 #endif // TRACE_CALC_YOUNG_CONFIG
ysr@777 751
ysr@777 752 from_so_length = new_so_length;
ysr@777 753 to_so_length = new_so_length;
ysr@777 754 fine_so_length = final_so_length;
ysr@777 755
ysr@777 756 pass = pass_type_final;
ysr@777 757 }
ysr@777 758 }
ysr@777 759 } else if (pass == pass_type_final) {
ysr@777 760 // we just finished the final (third) pass
ysr@777 761
ysr@777 762 if (!gc_eff_set)
ysr@777 763 // we didn't find a feasible config, so we'll just use the one
ysr@777 764 // we found during the second pass, which we saved
ysr@777 765 final_so_length = fine_so_length;
ysr@777 766
ysr@777 767 // and we're done!
ysr@777 768 done = true;
ysr@777 769 } else {
ysr@777 770 guarantee( false, "should never reach here" );
ysr@777 771 }
ysr@777 772
ysr@777 773 // we now go around the outermost loop
ysr@777 774 }
ysr@777 775
ysr@777 776 // we should have at least one region in the target young length
apetrusenko@980 777 _young_list_target_length =
apetrusenko@980 778 MAX2((size_t) 1, final_young_length + _recorded_survivor_regions);
ysr@777 779 if (final_so_length >= final_young_length)
ysr@777 780 // and we need to ensure that the S-O length is not greater than
ysr@777 781 // the target young length (this is being a bit careful)
ysr@777 782 final_so_length = 0;
ysr@777 783 _young_list_so_prefix_length = final_so_length;
ysr@777 784 guarantee( !_in_marking_window || !_last_full_young_gc ||
ysr@777 785 _young_list_so_prefix_length == 0, "invariant" );
ysr@777 786
ysr@777 787 // let's keep an eye of how long we spend on this calculation
ysr@777 788 // right now, I assume that we'll print it when we need it; we
ysr@777 789 // should really adde it to the breakdown of a pause
ysr@777 790 double end_time_sec = os::elapsedTime();
ysr@777 791 double elapsed_time_ms = (end_time_sec - start_time_sec) * 1000.0;
ysr@777 792
apetrusenko@980 793 #ifdef TRACE_CALC_YOUNG_CONFIG
ysr@777 794 // leave this in for debugging, just in case
ysr@777 795 gclog_or_tty->print_cr("target = %1.1lf ms, young = " SIZE_FORMAT
ysr@777 796 ", SO = " SIZE_FORMAT ", "
ysr@777 797 "elapsed %1.2lf ms, calcs: " SIZE_FORMAT " (%s%s) "
ysr@777 798 SIZE_FORMAT SIZE_FORMAT,
ysr@777 799 target_pause_time_ms,
ysr@777 800 _young_list_target_length - _young_list_so_prefix_length,
ysr@777 801 _young_list_so_prefix_length,
ysr@777 802 elapsed_time_ms,
ysr@777 803 calculations,
ysr@777 804 full_young_gcs() ? "full" : "partial",
tonyp@1794 805 during_initial_mark_pause() ? " i-m" : "",
apetrusenko@980 806 _in_marking_window,
apetrusenko@980 807 _in_marking_window_im);
apetrusenko@980 808 #endif // TRACE_CALC_YOUNG_CONFIG
ysr@777 809
ysr@777 810 if (_young_list_target_length < _young_list_min_length) {
ysr@777 811 // bummer; this means that, if we do a pause when the optimal
ysr@777 812 // config dictates, we'll violate the pause spacing target (the
ysr@777 813 // min length was calculate based on the application's current
ysr@777 814 // alloc rate);
ysr@777 815
ysr@777 816 // so, we have to bite the bullet, and allocate the minimum
ysr@777 817 // number. We'll violate our target, but we just can't meet it.
ysr@777 818
ysr@777 819 size_t so_length = 0;
ysr@777 820 // a note further up explains why we do not want an S-O length
ysr@777 821 // during marking
ysr@777 822 if (!_in_marking_window && !_last_full_young_gc)
ysr@777 823 // but we can still try to see whether we can find an optimal
ysr@777 824 // S-O length
ysr@777 825 so_length = calculate_optimal_so_length(_young_list_min_length);
ysr@777 826
apetrusenko@980 827 #ifdef TRACE_CALC_YOUNG_CONFIG
ysr@777 828 // leave this in for debugging, just in case
ysr@777 829 gclog_or_tty->print_cr("adjusted target length from "
ysr@777 830 SIZE_FORMAT " to " SIZE_FORMAT
ysr@777 831 ", SO " SIZE_FORMAT,
ysr@777 832 _young_list_target_length, _young_list_min_length,
ysr@777 833 so_length);
apetrusenko@980 834 #endif // TRACE_CALC_YOUNG_CONFIG
ysr@777 835
ysr@777 836 _young_list_target_length =
ysr@777 837 MAX2(_young_list_min_length, (size_t)1);
ysr@777 838 _young_list_so_prefix_length = so_length;
ysr@777 839 }
ysr@777 840 } else {
ysr@777 841 // we are in a partially-young mode or we've run out of regions (due
ysr@777 842 // to evacuation failure)
ysr@777 843
apetrusenko@980 844 #ifdef TRACE_CALC_YOUNG_CONFIG
ysr@777 845 // leave this in for debugging, just in case
ysr@777 846 gclog_or_tty->print_cr("(partial) setting target to " SIZE_FORMAT
ysr@777 847 ", SO " SIZE_FORMAT,
ysr@777 848 _young_list_min_length, 0);
apetrusenko@980 849 #endif // TRACE_CALC_YOUNG_CONFIG
ysr@777 850
ysr@777 851 // we'll do the pause as soon as possible and with no S-O prefix
ysr@777 852 // (see above for the reasons behind the latter)
ysr@777 853 _young_list_target_length =
ysr@777 854 MAX2(_young_list_min_length, (size_t) 1);
ysr@777 855 _young_list_so_prefix_length = 0;
ysr@777 856 }
ysr@777 857
ysr@777 858 _rs_lengths_prediction = rs_lengths;
ysr@777 859 }
ysr@777 860
ysr@777 861 // This is used by: calculate_optimal_so_length(length). It returns
ysr@777 862 // the GC eff and predicted pause time for a particular config
ysr@777 863 void
ysr@777 864 G1CollectorPolicy::predict_gc_eff(size_t young_length,
ysr@777 865 size_t so_length,
ysr@777 866 double base_time_ms,
ysr@777 867 double* ret_gc_eff,
ysr@777 868 double* ret_pause_time_ms) {
ysr@777 869 double so_time_ms = predict_scan_only_time_ms(so_length);
ysr@777 870 double accum_surv_rate_adj = 0.0;
ysr@777 871 if (so_length > 0)
ysr@777 872 accum_surv_rate_adj = accum_yg_surv_rate_pred((int)(so_length - 1));
ysr@777 873 double accum_surv_rate =
ysr@777 874 accum_yg_surv_rate_pred((int)(young_length - 1)) - accum_surv_rate_adj;
ysr@777 875 size_t bytes_to_copy =
ysr@777 876 (size_t) (accum_surv_rate * (double) HeapRegion::GrainBytes);
ysr@777 877 double copy_time_ms = predict_object_copy_time_ms(bytes_to_copy);
ysr@777 878 double young_other_time_ms =
ysr@777 879 predict_young_other_time_ms(young_length - so_length);
ysr@777 880 double pause_time_ms =
ysr@777 881 base_time_ms + so_time_ms + copy_time_ms + young_other_time_ms;
ysr@777 882 size_t reclaimed_bytes =
ysr@777 883 (young_length - so_length) * HeapRegion::GrainBytes - bytes_to_copy;
ysr@777 884 double gc_eff = (double) reclaimed_bytes / pause_time_ms;
ysr@777 885
ysr@777 886 *ret_gc_eff = gc_eff;
ysr@777 887 *ret_pause_time_ms = pause_time_ms;
ysr@777 888 }
ysr@777 889
ysr@777 890 // This is used by: calculate_young_list_target_config(rs_length). It
ysr@777 891 // returns the GC eff of a particular config. It returns false if that
ysr@777 892 // config violates any of the end conditions of the search in the
ysr@777 893 // calling method, or true upon success. The end conditions were put
ysr@777 894 // here since it's called twice and it was best not to replicate them
ysr@777 895 // in the caller. Also, passing the parameteres avoids having to
ysr@777 896 // recalculate them in the innermost loop.
ysr@777 897 bool
ysr@777 898 G1CollectorPolicy::predict_gc_eff(size_t young_length,
ysr@777 899 size_t so_length,
ysr@777 900 double base_time_with_so_ms,
ysr@777 901 size_t init_free_regions,
ysr@777 902 double target_pause_time_ms,
ysr@777 903 double* ret_gc_eff) {
ysr@777 904 *ret_gc_eff = 0.0;
ysr@777 905
ysr@777 906 if (young_length >= init_free_regions)
ysr@777 907 // end condition 1: not enough space for the young regions
ysr@777 908 return false;
ysr@777 909
ysr@777 910 double accum_surv_rate_adj = 0.0;
ysr@777 911 if (so_length > 0)
ysr@777 912 accum_surv_rate_adj = accum_yg_surv_rate_pred((int)(so_length - 1));
ysr@777 913 double accum_surv_rate =
ysr@777 914 accum_yg_surv_rate_pred((int)(young_length - 1)) - accum_surv_rate_adj;
ysr@777 915 size_t bytes_to_copy =
ysr@777 916 (size_t) (accum_surv_rate * (double) HeapRegion::GrainBytes);
ysr@777 917 double copy_time_ms = predict_object_copy_time_ms(bytes_to_copy);
ysr@777 918 double young_other_time_ms =
ysr@777 919 predict_young_other_time_ms(young_length - so_length);
ysr@777 920 double pause_time_ms =
ysr@777 921 base_time_with_so_ms + copy_time_ms + young_other_time_ms;
ysr@777 922
ysr@777 923 if (pause_time_ms > target_pause_time_ms)
ysr@777 924 // end condition 2: over the target pause time
ysr@777 925 return false;
ysr@777 926
ysr@777 927 size_t reclaimed_bytes =
ysr@777 928 (young_length - so_length) * HeapRegion::GrainBytes - bytes_to_copy;
ysr@777 929 size_t free_bytes =
ysr@777 930 (init_free_regions - young_length) * HeapRegion::GrainBytes;
ysr@777 931
ysr@777 932 if ((2.0 + sigma()) * (double) bytes_to_copy > (double) free_bytes)
ysr@777 933 // end condition 3: out of to-space (conservatively)
ysr@777 934 return false;
ysr@777 935
ysr@777 936 // success!
ysr@777 937 double gc_eff = (double) reclaimed_bytes / pause_time_ms;
ysr@777 938 *ret_gc_eff = gc_eff;
ysr@777 939
ysr@777 940 return true;
ysr@777 941 }
ysr@777 942
apetrusenko@980 943 double G1CollectorPolicy::predict_survivor_regions_evac_time() {
apetrusenko@980 944 double survivor_regions_evac_time = 0.0;
apetrusenko@980 945 for (HeapRegion * r = _recorded_survivor_head;
apetrusenko@980 946 r != NULL && r != _recorded_survivor_tail->get_next_young_region();
apetrusenko@980 947 r = r->get_next_young_region()) {
apetrusenko@980 948 survivor_regions_evac_time += predict_region_elapsed_time_ms(r, true);
apetrusenko@980 949 }
apetrusenko@980 950 return survivor_regions_evac_time;
apetrusenko@980 951 }
apetrusenko@980 952
ysr@777 953 void G1CollectorPolicy::check_prediction_validity() {
ysr@777 954 guarantee( adaptive_young_list_length(), "should not call this otherwise" );
ysr@777 955
ysr@777 956 size_t rs_lengths = _g1->young_list_sampled_rs_lengths();
ysr@777 957 if (rs_lengths > _rs_lengths_prediction) {
ysr@777 958 // add 10% to avoid having to recalculate often
ysr@777 959 size_t rs_lengths_prediction = rs_lengths * 1100 / 1000;
ysr@777 960 calculate_young_list_target_config(rs_lengths_prediction);
ysr@777 961 }
ysr@777 962 }
ysr@777 963
ysr@777 964 HeapWord* G1CollectorPolicy::mem_allocate_work(size_t size,
ysr@777 965 bool is_tlab,
ysr@777 966 bool* gc_overhead_limit_was_exceeded) {
ysr@777 967 guarantee(false, "Not using this policy feature yet.");
ysr@777 968 return NULL;
ysr@777 969 }
ysr@777 970
ysr@777 971 // This method controls how a collector handles one or more
ysr@777 972 // of its generations being fully allocated.
ysr@777 973 HeapWord* G1CollectorPolicy::satisfy_failed_allocation(size_t size,
ysr@777 974 bool is_tlab) {
ysr@777 975 guarantee(false, "Not using this policy feature yet.");
ysr@777 976 return NULL;
ysr@777 977 }
ysr@777 978
ysr@777 979
ysr@777 980 #ifndef PRODUCT
ysr@777 981 bool G1CollectorPolicy::verify_young_ages() {
ysr@777 982 HeapRegion* head = _g1->young_list_first_region();
ysr@777 983 return
ysr@777 984 verify_young_ages(head, _short_lived_surv_rate_group);
ysr@777 985 // also call verify_young_ages on any additional surv rate groups
ysr@777 986 }
ysr@777 987
ysr@777 988 bool
ysr@777 989 G1CollectorPolicy::verify_young_ages(HeapRegion* head,
ysr@777 990 SurvRateGroup *surv_rate_group) {
ysr@777 991 guarantee( surv_rate_group != NULL, "pre-condition" );
ysr@777 992
ysr@777 993 const char* name = surv_rate_group->name();
ysr@777 994 bool ret = true;
ysr@777 995 int prev_age = -1;
ysr@777 996
ysr@777 997 for (HeapRegion* curr = head;
ysr@777 998 curr != NULL;
ysr@777 999 curr = curr->get_next_young_region()) {
ysr@777 1000 SurvRateGroup* group = curr->surv_rate_group();
ysr@777 1001 if (group == NULL && !curr->is_survivor()) {
ysr@777 1002 gclog_or_tty->print_cr("## %s: encountered NULL surv_rate_group", name);
ysr@777 1003 ret = false;
ysr@777 1004 }
ysr@777 1005
ysr@777 1006 if (surv_rate_group == group) {
ysr@777 1007 int age = curr->age_in_surv_rate_group();
ysr@777 1008
ysr@777 1009 if (age < 0) {
ysr@777 1010 gclog_or_tty->print_cr("## %s: encountered negative age", name);
ysr@777 1011 ret = false;
ysr@777 1012 }
ysr@777 1013
ysr@777 1014 if (age <= prev_age) {
ysr@777 1015 gclog_or_tty->print_cr("## %s: region ages are not strictly increasing "
ysr@777 1016 "(%d, %d)", name, age, prev_age);
ysr@777 1017 ret = false;
ysr@777 1018 }
ysr@777 1019 prev_age = age;
ysr@777 1020 }
ysr@777 1021 }
ysr@777 1022
ysr@777 1023 return ret;
ysr@777 1024 }
ysr@777 1025 #endif // PRODUCT
ysr@777 1026
ysr@777 1027 void G1CollectorPolicy::record_full_collection_start() {
ysr@777 1028 _cur_collection_start_sec = os::elapsedTime();
ysr@777 1029 // Release the future to-space so that it is available for compaction into.
ysr@777 1030 _g1->set_full_collection();
ysr@777 1031 }
ysr@777 1032
ysr@777 1033 void G1CollectorPolicy::record_full_collection_end() {
ysr@777 1034 // Consider this like a collection pause for the purposes of allocation
ysr@777 1035 // since last pause.
ysr@777 1036 double end_sec = os::elapsedTime();
ysr@777 1037 double full_gc_time_sec = end_sec - _cur_collection_start_sec;
ysr@777 1038 double full_gc_time_ms = full_gc_time_sec * 1000.0;
ysr@777 1039
ysr@777 1040 _all_full_gc_times_ms->add(full_gc_time_ms);
ysr@777 1041
tonyp@1030 1042 update_recent_gc_times(end_sec, full_gc_time_ms);
ysr@777 1043
ysr@777 1044 _g1->clear_full_collection();
ysr@777 1045
ysr@777 1046 // "Nuke" the heuristics that control the fully/partially young GC
ysr@777 1047 // transitions and make sure we start with fully young GCs after the
ysr@777 1048 // Full GC.
ysr@777 1049 set_full_young_gcs(true);
ysr@777 1050 _last_full_young_gc = false;
ysr@777 1051 _should_revert_to_full_young_gcs = false;
tonyp@1794 1052 clear_initiate_conc_mark_if_possible();
tonyp@1794 1053 clear_during_initial_mark_pause();
ysr@777 1054 _known_garbage_bytes = 0;
ysr@777 1055 _known_garbage_ratio = 0.0;
ysr@777 1056 _in_marking_window = false;
ysr@777 1057 _in_marking_window_im = false;
ysr@777 1058
ysr@777 1059 _short_lived_surv_rate_group->record_scan_only_prefix(0);
ysr@777 1060 _short_lived_surv_rate_group->start_adding_regions();
ysr@777 1061 // also call this on any additional surv rate groups
ysr@777 1062
apetrusenko@980 1063 record_survivor_regions(0, NULL, NULL);
apetrusenko@980 1064
ysr@777 1065 _prev_region_num_young = _region_num_young;
ysr@777 1066 _prev_region_num_tenured = _region_num_tenured;
ysr@777 1067
ysr@777 1068 _free_regions_at_end_of_collection = _g1->free_regions();
ysr@777 1069 _scan_only_regions_at_end_of_collection = 0;
apetrusenko@980 1070 // Reset survivors SurvRateGroup.
apetrusenko@980 1071 _survivor_surv_rate_group->reset();
ysr@777 1072 calculate_young_list_min_length();
ysr@777 1073 calculate_young_list_target_config();
ysr@777 1074 }
ysr@777 1075
ysr@777 1076 void G1CollectorPolicy::record_before_bytes(size_t bytes) {
ysr@777 1077 _bytes_in_to_space_before_gc += bytes;
ysr@777 1078 }
ysr@777 1079
ysr@777 1080 void G1CollectorPolicy::record_after_bytes(size_t bytes) {
ysr@777 1081 _bytes_in_to_space_after_gc += bytes;
ysr@777 1082 }
ysr@777 1083
ysr@777 1084 void G1CollectorPolicy::record_stop_world_start() {
ysr@777 1085 _stop_world_start = os::elapsedTime();
ysr@777 1086 }
ysr@777 1087
ysr@777 1088 void G1CollectorPolicy::record_collection_pause_start(double start_time_sec,
ysr@777 1089 size_t start_used) {
ysr@777 1090 if (PrintGCDetails) {
ysr@777 1091 gclog_or_tty->stamp(PrintGCTimeStamps);
ysr@777 1092 gclog_or_tty->print("[GC pause");
ysr@777 1093 if (in_young_gc_mode())
ysr@777 1094 gclog_or_tty->print(" (%s)", full_young_gcs() ? "young" : "partial");
ysr@777 1095 }
ysr@777 1096
ysr@777 1097 assert(_g1->used_regions() == _g1->recalculate_used_regions(),
ysr@777 1098 "sanity");
tonyp@1071 1099 assert(_g1->used() == _g1->recalculate_used(), "sanity");
ysr@777 1100
ysr@777 1101 double s_w_t_ms = (start_time_sec - _stop_world_start) * 1000.0;
ysr@777 1102 _all_stop_world_times_ms->add(s_w_t_ms);
ysr@777 1103 _stop_world_start = 0.0;
ysr@777 1104
ysr@777 1105 _cur_collection_start_sec = start_time_sec;
ysr@777 1106 _cur_collection_pause_used_at_start_bytes = start_used;
ysr@777 1107 _cur_collection_pause_used_regions_at_start = _g1->used_regions();
ysr@777 1108 _pending_cards = _g1->pending_card_num();
ysr@777 1109 _max_pending_cards = _g1->max_pending_card_num();
ysr@777 1110
ysr@777 1111 _bytes_in_to_space_before_gc = 0;
ysr@777 1112 _bytes_in_to_space_after_gc = 0;
ysr@777 1113 _bytes_in_collection_set_before_gc = 0;
ysr@777 1114
ysr@777 1115 #ifdef DEBUG
ysr@777 1116 // initialise these to something well known so that we can spot
ysr@777 1117 // if they are not set properly
ysr@777 1118
ysr@777 1119 for (int i = 0; i < _parallel_gc_threads; ++i) {
ysr@777 1120 _par_last_ext_root_scan_times_ms[i] = -666.0;
ysr@777 1121 _par_last_mark_stack_scan_times_ms[i] = -666.0;
ysr@777 1122 _par_last_scan_only_times_ms[i] = -666.0;
ysr@777 1123 _par_last_scan_only_regions_scanned[i] = -666.0;
ysr@777 1124 _par_last_update_rs_start_times_ms[i] = -666.0;
ysr@777 1125 _par_last_update_rs_times_ms[i] = -666.0;
ysr@777 1126 _par_last_update_rs_processed_buffers[i] = -666.0;
ysr@777 1127 _par_last_scan_rs_start_times_ms[i] = -666.0;
ysr@777 1128 _par_last_scan_rs_times_ms[i] = -666.0;
ysr@777 1129 _par_last_scan_new_refs_times_ms[i] = -666.0;
ysr@777 1130 _par_last_obj_copy_times_ms[i] = -666.0;
ysr@777 1131 _par_last_termination_times_ms[i] = -666.0;
ysr@777 1132 }
ysr@777 1133 #endif
ysr@777 1134
ysr@777 1135 for (int i = 0; i < _aux_num; ++i) {
ysr@777 1136 _cur_aux_times_ms[i] = 0.0;
ysr@777 1137 _cur_aux_times_set[i] = false;
ysr@777 1138 }
ysr@777 1139
ysr@777 1140 _satb_drain_time_set = false;
ysr@777 1141 _last_satb_drain_processed_buffers = -1;
ysr@777 1142
ysr@777 1143 if (in_young_gc_mode())
ysr@777 1144 _last_young_gc_full = false;
ysr@777 1145
ysr@777 1146
ysr@777 1147 // do that for any other surv rate groups
ysr@777 1148 _short_lived_surv_rate_group->stop_adding_regions();
ysr@777 1149 size_t short_lived_so_length = _young_list_so_prefix_length;
ysr@777 1150 _short_lived_surv_rate_group->record_scan_only_prefix(short_lived_so_length);
ysr@777 1151 tag_scan_only(short_lived_so_length);
tonyp@1717 1152 _survivors_age_table.clear();
apetrusenko@980 1153
ysr@777 1154 assert( verify_young_ages(), "region age verification" );
ysr@777 1155 }
ysr@777 1156
ysr@777 1157 void G1CollectorPolicy::tag_scan_only(size_t short_lived_scan_only_length) {
ysr@777 1158 // done in a way that it can be extended for other surv rate groups too...
ysr@777 1159
ysr@777 1160 HeapRegion* head = _g1->young_list_first_region();
ysr@777 1161 bool finished_short_lived = (short_lived_scan_only_length == 0);
ysr@777 1162
ysr@777 1163 if (finished_short_lived)
ysr@777 1164 return;
ysr@777 1165
ysr@777 1166 for (HeapRegion* curr = head;
ysr@777 1167 curr != NULL;
ysr@777 1168 curr = curr->get_next_young_region()) {
ysr@777 1169 SurvRateGroup* surv_rate_group = curr->surv_rate_group();
ysr@777 1170 int age = curr->age_in_surv_rate_group();
ysr@777 1171
ysr@777 1172 if (surv_rate_group == _short_lived_surv_rate_group) {
ysr@777 1173 if ((size_t)age < short_lived_scan_only_length)
ysr@777 1174 curr->set_scan_only();
ysr@777 1175 else
ysr@777 1176 finished_short_lived = true;
ysr@777 1177 }
ysr@777 1178
ysr@777 1179
ysr@777 1180 if (finished_short_lived)
ysr@777 1181 return;
ysr@777 1182 }
ysr@777 1183
ysr@777 1184 guarantee( false, "we should never reach here" );
ysr@777 1185 }
ysr@777 1186
ysr@777 1187 void G1CollectorPolicy::record_mark_closure_time(double mark_closure_time_ms) {
ysr@777 1188 _mark_closure_time_ms = mark_closure_time_ms;
ysr@777 1189 }
ysr@777 1190
ysr@777 1191 void G1CollectorPolicy::record_concurrent_mark_init_start() {
ysr@777 1192 _mark_init_start_sec = os::elapsedTime();
ysr@777 1193 guarantee(!in_young_gc_mode(), "should not do be here in young GC mode");
ysr@777 1194 }
ysr@777 1195
ysr@777 1196 void G1CollectorPolicy::record_concurrent_mark_init_end_pre(double
ysr@777 1197 mark_init_elapsed_time_ms) {
ysr@777 1198 _during_marking = true;
tonyp@1794 1199 assert(!initiate_conc_mark_if_possible(), "we should have cleared it by now");
tonyp@1794 1200 clear_during_initial_mark_pause();
ysr@777 1201 _cur_mark_stop_world_time_ms = mark_init_elapsed_time_ms;
ysr@777 1202 }
ysr@777 1203
ysr@777 1204 void G1CollectorPolicy::record_concurrent_mark_init_end() {
ysr@777 1205 double end_time_sec = os::elapsedTime();
ysr@777 1206 double elapsed_time_ms = (end_time_sec - _mark_init_start_sec) * 1000.0;
ysr@777 1207 _concurrent_mark_init_times_ms->add(elapsed_time_ms);
ysr@777 1208 record_concurrent_mark_init_end_pre(elapsed_time_ms);
ysr@777 1209
ysr@777 1210 _mmu_tracker->add_pause(_mark_init_start_sec, end_time_sec, true);
ysr@777 1211 }
ysr@777 1212
ysr@777 1213 void G1CollectorPolicy::record_concurrent_mark_remark_start() {
ysr@777 1214 _mark_remark_start_sec = os::elapsedTime();
ysr@777 1215 _during_marking = false;
ysr@777 1216 }
ysr@777 1217
ysr@777 1218 void G1CollectorPolicy::record_concurrent_mark_remark_end() {
ysr@777 1219 double end_time_sec = os::elapsedTime();
ysr@777 1220 double elapsed_time_ms = (end_time_sec - _mark_remark_start_sec)*1000.0;
ysr@777 1221 _concurrent_mark_remark_times_ms->add(elapsed_time_ms);
ysr@777 1222 _cur_mark_stop_world_time_ms += elapsed_time_ms;
ysr@777 1223 _prev_collection_pause_end_ms += elapsed_time_ms;
ysr@777 1224
ysr@777 1225 _mmu_tracker->add_pause(_mark_remark_start_sec, end_time_sec, true);
ysr@777 1226 }
ysr@777 1227
ysr@777 1228 void G1CollectorPolicy::record_concurrent_mark_cleanup_start() {
ysr@777 1229 _mark_cleanup_start_sec = os::elapsedTime();
ysr@777 1230 }
ysr@777 1231
ysr@777 1232 void
ysr@777 1233 G1CollectorPolicy::record_concurrent_mark_cleanup_end(size_t freed_bytes,
ysr@777 1234 size_t max_live_bytes) {
ysr@777 1235 record_concurrent_mark_cleanup_end_work1(freed_bytes, max_live_bytes);
ysr@777 1236 record_concurrent_mark_cleanup_end_work2();
ysr@777 1237 }
ysr@777 1238
ysr@777 1239 void
ysr@777 1240 G1CollectorPolicy::
ysr@777 1241 record_concurrent_mark_cleanup_end_work1(size_t freed_bytes,
ysr@777 1242 size_t max_live_bytes) {
ysr@777 1243 if (_n_marks < 2) _n_marks++;
ysr@777 1244 if (G1PolicyVerbose > 0)
ysr@777 1245 gclog_or_tty->print_cr("At end of marking, max_live is " SIZE_FORMAT " MB "
ysr@777 1246 " (of " SIZE_FORMAT " MB heap).",
ysr@777 1247 max_live_bytes/M, _g1->capacity()/M);
ysr@777 1248 }
ysr@777 1249
ysr@777 1250 // The important thing about this is that it includes "os::elapsedTime".
ysr@777 1251 void G1CollectorPolicy::record_concurrent_mark_cleanup_end_work2() {
ysr@777 1252 double end_time_sec = os::elapsedTime();
ysr@777 1253 double elapsed_time_ms = (end_time_sec - _mark_cleanup_start_sec)*1000.0;
ysr@777 1254 _concurrent_mark_cleanup_times_ms->add(elapsed_time_ms);
ysr@777 1255 _cur_mark_stop_world_time_ms += elapsed_time_ms;
ysr@777 1256 _prev_collection_pause_end_ms += elapsed_time_ms;
ysr@777 1257
ysr@777 1258 _mmu_tracker->add_pause(_mark_cleanup_start_sec, end_time_sec, true);
ysr@777 1259
ysr@777 1260 _num_markings++;
ysr@777 1261
ysr@777 1262 // We did a marking, so reset the "since_last_mark" variables.
ysr@777 1263 double considerConcMarkCost = 1.0;
ysr@777 1264 // If there are available processors, concurrent activity is free...
ysr@777 1265 if (Threads::number_of_non_daemon_threads() * 2 <
ysr@777 1266 os::active_processor_count()) {
ysr@777 1267 considerConcMarkCost = 0.0;
ysr@777 1268 }
ysr@777 1269 _n_pauses_at_mark_end = _n_pauses;
ysr@777 1270 _n_marks_since_last_pause++;
ysr@777 1271 }
ysr@777 1272
ysr@777 1273 void
ysr@777 1274 G1CollectorPolicy::record_concurrent_mark_cleanup_completed() {
ysr@777 1275 if (in_young_gc_mode()) {
ysr@777 1276 _should_revert_to_full_young_gcs = false;
ysr@777 1277 _last_full_young_gc = true;
ysr@777 1278 _in_marking_window = false;
ysr@777 1279 if (adaptive_young_list_length())
ysr@777 1280 calculate_young_list_target_config();
ysr@777 1281 }
ysr@777 1282 }
ysr@777 1283
ysr@777 1284 void G1CollectorPolicy::record_concurrent_pause() {
ysr@777 1285 if (_stop_world_start > 0.0) {
ysr@777 1286 double yield_ms = (os::elapsedTime() - _stop_world_start) * 1000.0;
ysr@777 1287 _all_yield_times_ms->add(yield_ms);
ysr@777 1288 }
ysr@777 1289 }
ysr@777 1290
ysr@777 1291 void G1CollectorPolicy::record_concurrent_pause_end() {
ysr@777 1292 }
ysr@777 1293
ysr@777 1294 void G1CollectorPolicy::record_collection_pause_end_CH_strong_roots() {
ysr@777 1295 _cur_CH_strong_roots_end_sec = os::elapsedTime();
ysr@777 1296 _cur_CH_strong_roots_dur_ms =
ysr@777 1297 (_cur_CH_strong_roots_end_sec - _cur_collection_start_sec) * 1000.0;
ysr@777 1298 }
ysr@777 1299
ysr@777 1300 void G1CollectorPolicy::record_collection_pause_end_G1_strong_roots() {
ysr@777 1301 _cur_G1_strong_roots_end_sec = os::elapsedTime();
ysr@777 1302 _cur_G1_strong_roots_dur_ms =
ysr@777 1303 (_cur_G1_strong_roots_end_sec - _cur_CH_strong_roots_end_sec) * 1000.0;
ysr@777 1304 }
ysr@777 1305
ysr@777 1306 template<class T>
ysr@777 1307 T sum_of(T* sum_arr, int start, int n, int N) {
ysr@777 1308 T sum = (T)0;
ysr@777 1309 for (int i = 0; i < n; i++) {
ysr@777 1310 int j = (start + i) % N;
ysr@777 1311 sum += sum_arr[j];
ysr@777 1312 }
ysr@777 1313 return sum;
ysr@777 1314 }
ysr@777 1315
ysr@777 1316 void G1CollectorPolicy::print_par_stats (int level,
ysr@777 1317 const char* str,
ysr@777 1318 double* data,
ysr@777 1319 bool summary) {
ysr@777 1320 double min = data[0], max = data[0];
ysr@777 1321 double total = 0.0;
ysr@777 1322 int j;
ysr@777 1323 for (j = 0; j < level; ++j)
ysr@777 1324 gclog_or_tty->print(" ");
ysr@777 1325 gclog_or_tty->print("[%s (ms):", str);
ysr@777 1326 for (uint i = 0; i < ParallelGCThreads; ++i) {
ysr@777 1327 double val = data[i];
ysr@777 1328 if (val < min)
ysr@777 1329 min = val;
ysr@777 1330 if (val > max)
ysr@777 1331 max = val;
ysr@777 1332 total += val;
ysr@777 1333 gclog_or_tty->print(" %3.1lf", val);
ysr@777 1334 }
ysr@777 1335 if (summary) {
ysr@777 1336 gclog_or_tty->print_cr("");
ysr@777 1337 double avg = total / (double) ParallelGCThreads;
ysr@777 1338 gclog_or_tty->print(" ");
ysr@777 1339 for (j = 0; j < level; ++j)
ysr@777 1340 gclog_or_tty->print(" ");
ysr@777 1341 gclog_or_tty->print("Avg: %5.1lf, Min: %5.1lf, Max: %5.1lf",
ysr@777 1342 avg, min, max);
ysr@777 1343 }
ysr@777 1344 gclog_or_tty->print_cr("]");
ysr@777 1345 }
ysr@777 1346
ysr@777 1347 void G1CollectorPolicy::print_par_buffers (int level,
ysr@777 1348 const char* str,
ysr@777 1349 double* data,
ysr@777 1350 bool summary) {
ysr@777 1351 double min = data[0], max = data[0];
ysr@777 1352 double total = 0.0;
ysr@777 1353 int j;
ysr@777 1354 for (j = 0; j < level; ++j)
ysr@777 1355 gclog_or_tty->print(" ");
ysr@777 1356 gclog_or_tty->print("[%s :", str);
ysr@777 1357 for (uint i = 0; i < ParallelGCThreads; ++i) {
ysr@777 1358 double val = data[i];
ysr@777 1359 if (val < min)
ysr@777 1360 min = val;
ysr@777 1361 if (val > max)
ysr@777 1362 max = val;
ysr@777 1363 total += val;
ysr@777 1364 gclog_or_tty->print(" %d", (int) val);
ysr@777 1365 }
ysr@777 1366 if (summary) {
ysr@777 1367 gclog_or_tty->print_cr("");
ysr@777 1368 double avg = total / (double) ParallelGCThreads;
ysr@777 1369 gclog_or_tty->print(" ");
ysr@777 1370 for (j = 0; j < level; ++j)
ysr@777 1371 gclog_or_tty->print(" ");
ysr@777 1372 gclog_or_tty->print("Sum: %d, Avg: %d, Min: %d, Max: %d",
ysr@777 1373 (int)total, (int)avg, (int)min, (int)max);
ysr@777 1374 }
ysr@777 1375 gclog_or_tty->print_cr("]");
ysr@777 1376 }
ysr@777 1377
ysr@777 1378 void G1CollectorPolicy::print_stats (int level,
ysr@777 1379 const char* str,
ysr@777 1380 double value) {
ysr@777 1381 for (int j = 0; j < level; ++j)
ysr@777 1382 gclog_or_tty->print(" ");
ysr@777 1383 gclog_or_tty->print_cr("[%s: %5.1lf ms]", str, value);
ysr@777 1384 }
ysr@777 1385
ysr@777 1386 void G1CollectorPolicy::print_stats (int level,
ysr@777 1387 const char* str,
ysr@777 1388 int value) {
ysr@777 1389 for (int j = 0; j < level; ++j)
ysr@777 1390 gclog_or_tty->print(" ");
ysr@777 1391 gclog_or_tty->print_cr("[%s: %d]", str, value);
ysr@777 1392 }
ysr@777 1393
ysr@777 1394 double G1CollectorPolicy::avg_value (double* data) {
ysr@777 1395 if (ParallelGCThreads > 0) {
ysr@777 1396 double ret = 0.0;
ysr@777 1397 for (uint i = 0; i < ParallelGCThreads; ++i)
ysr@777 1398 ret += data[i];
ysr@777 1399 return ret / (double) ParallelGCThreads;
ysr@777 1400 } else {
ysr@777 1401 return data[0];
ysr@777 1402 }
ysr@777 1403 }
ysr@777 1404
ysr@777 1405 double G1CollectorPolicy::max_value (double* data) {
ysr@777 1406 if (ParallelGCThreads > 0) {
ysr@777 1407 double ret = data[0];
ysr@777 1408 for (uint i = 1; i < ParallelGCThreads; ++i)
ysr@777 1409 if (data[i] > ret)
ysr@777 1410 ret = data[i];
ysr@777 1411 return ret;
ysr@777 1412 } else {
ysr@777 1413 return data[0];
ysr@777 1414 }
ysr@777 1415 }
ysr@777 1416
ysr@777 1417 double G1CollectorPolicy::sum_of_values (double* data) {
ysr@777 1418 if (ParallelGCThreads > 0) {
ysr@777 1419 double sum = 0.0;
ysr@777 1420 for (uint i = 0; i < ParallelGCThreads; i++)
ysr@777 1421 sum += data[i];
ysr@777 1422 return sum;
ysr@777 1423 } else {
ysr@777 1424 return data[0];
ysr@777 1425 }
ysr@777 1426 }
ysr@777 1427
ysr@777 1428 double G1CollectorPolicy::max_sum (double* data1,
ysr@777 1429 double* data2) {
ysr@777 1430 double ret = data1[0] + data2[0];
ysr@777 1431
ysr@777 1432 if (ParallelGCThreads > 0) {
ysr@777 1433 for (uint i = 1; i < ParallelGCThreads; ++i) {
ysr@777 1434 double data = data1[i] + data2[i];
ysr@777 1435 if (data > ret)
ysr@777 1436 ret = data;
ysr@777 1437 }
ysr@777 1438 }
ysr@777 1439 return ret;
ysr@777 1440 }
ysr@777 1441
ysr@777 1442 // Anything below that is considered to be zero
ysr@777 1443 #define MIN_TIMER_GRANULARITY 0.0000001
ysr@777 1444
apetrusenko@1112 1445 void G1CollectorPolicy::record_collection_pause_end(bool abandoned) {
ysr@777 1446 double end_time_sec = os::elapsedTime();
ysr@777 1447 double elapsed_ms = _last_pause_time_ms;
ysr@777 1448 bool parallel = ParallelGCThreads > 0;
ysr@777 1449 double evac_ms = (end_time_sec - _cur_G1_strong_roots_end_sec) * 1000.0;
ysr@777 1450 size_t rs_size =
ysr@777 1451 _cur_collection_pause_used_regions_at_start - collection_set_size();
ysr@777 1452 size_t cur_used_bytes = _g1->used();
ysr@777 1453 assert(cur_used_bytes == _g1->recalculate_used(), "It should!");
ysr@777 1454 bool last_pause_included_initial_mark = false;
tonyp@1030 1455 bool update_stats = !abandoned && !_g1->evacuation_failed();
ysr@777 1456
ysr@777 1457 #ifndef PRODUCT
ysr@777 1458 if (G1YoungSurvRateVerbose) {
ysr@777 1459 gclog_or_tty->print_cr("");
ysr@777 1460 _short_lived_surv_rate_group->print();
ysr@777 1461 // do that for any other surv rate groups too
ysr@777 1462 }
ysr@777 1463 #endif // PRODUCT
ysr@777 1464
ysr@777 1465 if (in_young_gc_mode()) {
tonyp@1794 1466 last_pause_included_initial_mark = during_initial_mark_pause();
ysr@777 1467 if (last_pause_included_initial_mark)
ysr@777 1468 record_concurrent_mark_init_end_pre(0.0);
ysr@777 1469
ysr@777 1470 size_t min_used_targ =
tonyp@1718 1471 (_g1->capacity() / 100) * InitiatingHeapOccupancyPercent;
ysr@777 1472
tonyp@1794 1473
tonyp@1794 1474 if (!_g1->mark_in_progress() && !_last_full_young_gc) {
tonyp@1794 1475 assert(!last_pause_included_initial_mark, "invariant");
tonyp@1794 1476 if (cur_used_bytes > min_used_targ &&
tonyp@1794 1477 cur_used_bytes > _prev_collection_pause_used_at_end_bytes) {
tonyp@1794 1478 assert(!during_initial_mark_pause(), "we should not see this here");
tonyp@1794 1479
tonyp@1794 1480 // Note: this might have already been set, if during the last
tonyp@1794 1481 // pause we decided to start a cycle but at the beginning of
tonyp@1794 1482 // this pause we decided to postpone it. That's OK.
tonyp@1794 1483 set_initiate_conc_mark_if_possible();
ysr@777 1484 }
ysr@777 1485 }
ysr@777 1486
ysr@777 1487 _prev_collection_pause_used_at_end_bytes = cur_used_bytes;
ysr@777 1488 }
ysr@777 1489
ysr@777 1490 _mmu_tracker->add_pause(end_time_sec - elapsed_ms/1000.0,
ysr@777 1491 end_time_sec, false);
ysr@777 1492
ysr@777 1493 guarantee(_cur_collection_pause_used_regions_at_start >=
ysr@777 1494 collection_set_size(),
ysr@777 1495 "Negative RS size?");
ysr@777 1496
ysr@777 1497 // This assert is exempted when we're doing parallel collection pauses,
ysr@777 1498 // because the fragmentation caused by the parallel GC allocation buffers
ysr@777 1499 // can lead to more memory being used during collection than was used
ysr@777 1500 // before. Best leave this out until the fragmentation problem is fixed.
ysr@777 1501 // Pauses in which evacuation failed can also lead to negative
ysr@777 1502 // collections, since no space is reclaimed from a region containing an
ysr@777 1503 // object whose evacuation failed.
ysr@777 1504 // Further, we're now always doing parallel collection. But I'm still
ysr@777 1505 // leaving this here as a placeholder for a more precise assertion later.
ysr@777 1506 // (DLD, 10/05.)
ysr@777 1507 assert((true || parallel) // Always using GC LABs now.
ysr@777 1508 || _g1->evacuation_failed()
ysr@777 1509 || _cur_collection_pause_used_at_start_bytes >= cur_used_bytes,
ysr@777 1510 "Negative collection");
ysr@777 1511
ysr@777 1512 size_t freed_bytes =
ysr@777 1513 _cur_collection_pause_used_at_start_bytes - cur_used_bytes;
ysr@777 1514 size_t surviving_bytes = _collection_set_bytes_used_before - freed_bytes;
ysr@777 1515 double survival_fraction =
ysr@777 1516 (double)surviving_bytes/
ysr@777 1517 (double)_collection_set_bytes_used_before;
ysr@777 1518
ysr@777 1519 _n_pauses++;
ysr@777 1520
tonyp@1030 1521 if (update_stats) {
ysr@777 1522 _recent_CH_strong_roots_times_ms->add(_cur_CH_strong_roots_dur_ms);
ysr@777 1523 _recent_G1_strong_roots_times_ms->add(_cur_G1_strong_roots_dur_ms);
ysr@777 1524 _recent_evac_times_ms->add(evac_ms);
ysr@777 1525 _recent_pause_times_ms->add(elapsed_ms);
ysr@777 1526
ysr@777 1527 _recent_rs_sizes->add(rs_size);
ysr@777 1528
ysr@777 1529 // We exempt parallel collection from this check because Alloc Buffer
ysr@777 1530 // fragmentation can produce negative collections. Same with evac
ysr@777 1531 // failure.
ysr@777 1532 // Further, we're now always doing parallel collection. But I'm still
ysr@777 1533 // leaving this here as a placeholder for a more precise assertion later.
ysr@777 1534 // (DLD, 10/05.
ysr@777 1535 assert((true || parallel)
ysr@777 1536 || _g1->evacuation_failed()
ysr@777 1537 || surviving_bytes <= _collection_set_bytes_used_before,
ysr@777 1538 "Or else negative collection!");
ysr@777 1539 _recent_CS_bytes_used_before->add(_collection_set_bytes_used_before);
ysr@777 1540 _recent_CS_bytes_surviving->add(surviving_bytes);
ysr@777 1541
ysr@777 1542 // this is where we update the allocation rate of the application
ysr@777 1543 double app_time_ms =
ysr@777 1544 (_cur_collection_start_sec * 1000.0 - _prev_collection_pause_end_ms);
ysr@777 1545 if (app_time_ms < MIN_TIMER_GRANULARITY) {
ysr@777 1546 // This usually happens due to the timer not having the required
ysr@777 1547 // granularity. Some Linuxes are the usual culprits.
ysr@777 1548 // We'll just set it to something (arbitrarily) small.
ysr@777 1549 app_time_ms = 1.0;
ysr@777 1550 }
ysr@777 1551 size_t regions_allocated =
ysr@777 1552 (_region_num_young - _prev_region_num_young) +
ysr@777 1553 (_region_num_tenured - _prev_region_num_tenured);
ysr@777 1554 double alloc_rate_ms = (double) regions_allocated / app_time_ms;
ysr@777 1555 _alloc_rate_ms_seq->add(alloc_rate_ms);
ysr@777 1556 _prev_region_num_young = _region_num_young;
ysr@777 1557 _prev_region_num_tenured = _region_num_tenured;
ysr@777 1558
ysr@777 1559 double interval_ms =
ysr@777 1560 (end_time_sec - _recent_prev_end_times_for_all_gcs_sec->oldest()) * 1000.0;
ysr@777 1561 update_recent_gc_times(end_time_sec, elapsed_ms);
ysr@777 1562 _recent_avg_pause_time_ratio = _recent_gc_times_ms->sum()/interval_ms;
ysr@1521 1563 if (recent_avg_pause_time_ratio() < 0.0 ||
ysr@1521 1564 (recent_avg_pause_time_ratio() - 1.0 > 0.0)) {
ysr@1521 1565 #ifndef PRODUCT
ysr@1521 1566 // Dump info to allow post-facto debugging
ysr@1521 1567 gclog_or_tty->print_cr("recent_avg_pause_time_ratio() out of bounds");
ysr@1521 1568 gclog_or_tty->print_cr("-------------------------------------------");
ysr@1521 1569 gclog_or_tty->print_cr("Recent GC Times (ms):");
ysr@1521 1570 _recent_gc_times_ms->dump();
ysr@1521 1571 gclog_or_tty->print_cr("(End Time=%3.3f) Recent GC End Times (s):", end_time_sec);
ysr@1521 1572 _recent_prev_end_times_for_all_gcs_sec->dump();
ysr@1521 1573 gclog_or_tty->print_cr("GC = %3.3f, Interval = %3.3f, Ratio = %3.3f",
ysr@1521 1574 _recent_gc_times_ms->sum(), interval_ms, recent_avg_pause_time_ratio());
ysr@1522 1575 // In debug mode, terminate the JVM if the user wants to debug at this point.
ysr@1522 1576 assert(!G1FailOnFPError, "Debugging data for CR 6898948 has been dumped above");
ysr@1522 1577 #endif // !PRODUCT
ysr@1522 1578 // Clip ratio between 0.0 and 1.0, and continue. This will be fixed in
ysr@1522 1579 // CR 6902692 by redoing the manner in which the ratio is incrementally computed.
ysr@1521 1580 if (_recent_avg_pause_time_ratio < 0.0) {
ysr@1521 1581 _recent_avg_pause_time_ratio = 0.0;
ysr@1521 1582 } else {
ysr@1521 1583 assert(_recent_avg_pause_time_ratio - 1.0 > 0.0, "Ctl-point invariant");
ysr@1521 1584 _recent_avg_pause_time_ratio = 1.0;
ysr@1521 1585 }
ysr@1521 1586 }
ysr@777 1587 }
ysr@777 1588
ysr@777 1589 if (G1PolicyVerbose > 1) {
ysr@777 1590 gclog_or_tty->print_cr(" Recording collection pause(%d)", _n_pauses);
ysr@777 1591 }
ysr@777 1592
ysr@777 1593 PauseSummary* summary;
apetrusenko@1112 1594 if (abandoned) {
apetrusenko@1112 1595 summary = _abandoned_summary;
apetrusenko@1112 1596 } else {
apetrusenko@1112 1597 summary = _summary;
ysr@777 1598 }
ysr@777 1599
ysr@777 1600 double ext_root_scan_time = avg_value(_par_last_ext_root_scan_times_ms);
ysr@777 1601 double mark_stack_scan_time = avg_value(_par_last_mark_stack_scan_times_ms);
ysr@777 1602 double scan_only_time = avg_value(_par_last_scan_only_times_ms);
ysr@777 1603 double scan_only_regions_scanned =
ysr@777 1604 sum_of_values(_par_last_scan_only_regions_scanned);
ysr@777 1605 double update_rs_time = avg_value(_par_last_update_rs_times_ms);
ysr@777 1606 double update_rs_processed_buffers =
ysr@777 1607 sum_of_values(_par_last_update_rs_processed_buffers);
ysr@777 1608 double scan_rs_time = avg_value(_par_last_scan_rs_times_ms);
ysr@777 1609 double obj_copy_time = avg_value(_par_last_obj_copy_times_ms);
ysr@777 1610 double termination_time = avg_value(_par_last_termination_times_ms);
ysr@777 1611
tonyp@1083 1612 double parallel_other_time = _cur_collection_par_time_ms -
tonyp@1083 1613 (update_rs_time + ext_root_scan_time + mark_stack_scan_time +
tonyp@1083 1614 scan_only_time + scan_rs_time + obj_copy_time + termination_time);
tonyp@1030 1615 if (update_stats) {
ysr@777 1616 MainBodySummary* body_summary = summary->main_body_summary();
ysr@777 1617 guarantee(body_summary != NULL, "should not be null!");
ysr@777 1618
ysr@777 1619 if (_satb_drain_time_set)
ysr@777 1620 body_summary->record_satb_drain_time_ms(_cur_satb_drain_time_ms);
ysr@777 1621 else
ysr@777 1622 body_summary->record_satb_drain_time_ms(0.0);
ysr@777 1623 body_summary->record_ext_root_scan_time_ms(ext_root_scan_time);
ysr@777 1624 body_summary->record_mark_stack_scan_time_ms(mark_stack_scan_time);
ysr@777 1625 body_summary->record_scan_only_time_ms(scan_only_time);
ysr@777 1626 body_summary->record_update_rs_time_ms(update_rs_time);
ysr@777 1627 body_summary->record_scan_rs_time_ms(scan_rs_time);
ysr@777 1628 body_summary->record_obj_copy_time_ms(obj_copy_time);
ysr@777 1629 if (parallel) {
ysr@777 1630 body_summary->record_parallel_time_ms(_cur_collection_par_time_ms);
ysr@777 1631 body_summary->record_clear_ct_time_ms(_cur_clear_ct_time_ms);
ysr@777 1632 body_summary->record_termination_time_ms(termination_time);
ysr@777 1633 body_summary->record_parallel_other_time_ms(parallel_other_time);
ysr@777 1634 }
ysr@777 1635 body_summary->record_mark_closure_time_ms(_mark_closure_time_ms);
ysr@777 1636 }
ysr@777 1637
ysr@777 1638 if (G1PolicyVerbose > 1) {
ysr@777 1639 gclog_or_tty->print_cr(" ET: %10.6f ms (avg: %10.6f ms)\n"
ysr@777 1640 " CH Strong: %10.6f ms (avg: %10.6f ms)\n"
ysr@777 1641 " G1 Strong: %10.6f ms (avg: %10.6f ms)\n"
ysr@777 1642 " Evac: %10.6f ms (avg: %10.6f ms)\n"
ysr@777 1643 " ET-RS: %10.6f ms (avg: %10.6f ms)\n"
ysr@777 1644 " |RS|: " SIZE_FORMAT,
ysr@777 1645 elapsed_ms, recent_avg_time_for_pauses_ms(),
ysr@777 1646 _cur_CH_strong_roots_dur_ms, recent_avg_time_for_CH_strong_ms(),
ysr@777 1647 _cur_G1_strong_roots_dur_ms, recent_avg_time_for_G1_strong_ms(),
ysr@777 1648 evac_ms, recent_avg_time_for_evac_ms(),
ysr@777 1649 scan_rs_time,
ysr@777 1650 recent_avg_time_for_pauses_ms() -
ysr@777 1651 recent_avg_time_for_G1_strong_ms(),
ysr@777 1652 rs_size);
ysr@777 1653
ysr@777 1654 gclog_or_tty->print_cr(" Used at start: " SIZE_FORMAT"K"
ysr@777 1655 " At end " SIZE_FORMAT "K\n"
ysr@777 1656 " garbage : " SIZE_FORMAT "K"
ysr@777 1657 " of " SIZE_FORMAT "K\n"
ysr@777 1658 " survival : %6.2f%% (%6.2f%% avg)",
ysr@777 1659 _cur_collection_pause_used_at_start_bytes/K,
ysr@777 1660 _g1->used()/K, freed_bytes/K,
ysr@777 1661 _collection_set_bytes_used_before/K,
ysr@777 1662 survival_fraction*100.0,
ysr@777 1663 recent_avg_survival_fraction()*100.0);
ysr@777 1664 gclog_or_tty->print_cr(" Recent %% gc pause time: %6.2f",
ysr@777 1665 recent_avg_pause_time_ratio() * 100.0);
ysr@777 1666 }
ysr@777 1667
ysr@777 1668 double other_time_ms = elapsed_ms;
ysr@777 1669
ysr@777 1670 if (!abandoned) {
ysr@777 1671 if (_satb_drain_time_set)
ysr@777 1672 other_time_ms -= _cur_satb_drain_time_ms;
ysr@777 1673
ysr@777 1674 if (parallel)
ysr@777 1675 other_time_ms -= _cur_collection_par_time_ms + _cur_clear_ct_time_ms;
ysr@777 1676 else
ysr@777 1677 other_time_ms -=
ysr@777 1678 update_rs_time +
ysr@777 1679 ext_root_scan_time + mark_stack_scan_time + scan_only_time +
ysr@777 1680 scan_rs_time + obj_copy_time;
ysr@777 1681 }
ysr@777 1682
ysr@777 1683 if (PrintGCDetails) {
ysr@777 1684 gclog_or_tty->print_cr("%s%s, %1.8lf secs]",
apetrusenko@1112 1685 abandoned ? " (abandoned)" : "",
ysr@777 1686 (last_pause_included_initial_mark) ? " (initial-mark)" : "",
ysr@777 1687 elapsed_ms / 1000.0);
ysr@777 1688
ysr@777 1689 if (!abandoned) {
apetrusenko@1112 1690 if (_satb_drain_time_set) {
ysr@777 1691 print_stats(1, "SATB Drain Time", _cur_satb_drain_time_ms);
apetrusenko@1112 1692 }
apetrusenko@1112 1693 if (_last_satb_drain_processed_buffers >= 0) {
ysr@777 1694 print_stats(2, "Processed Buffers", _last_satb_drain_processed_buffers);
apetrusenko@1112 1695 }
apetrusenko@1112 1696 if (parallel) {
apetrusenko@1112 1697 print_stats(1, "Parallel Time", _cur_collection_par_time_ms);
apetrusenko@1112 1698 print_par_stats(2, "Update RS (Start)", _par_last_update_rs_start_times_ms, false);
apetrusenko@1112 1699 print_par_stats(2, "Update RS", _par_last_update_rs_times_ms);
iveresov@1229 1700 print_par_buffers(3, "Processed Buffers",
iveresov@1229 1701 _par_last_update_rs_processed_buffers, true);
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);
apetrusenko@1112 1712 } else {
apetrusenko@1112 1713 print_stats(1, "Update RS", update_rs_time);
iveresov@1229 1714 print_stats(2, "Processed Buffers",
iveresov@1229 1715 (int)update_rs_processed_buffers);
ysr@777 1716 print_stats(1, "Ext Root Scanning", ext_root_scan_time);
ysr@777 1717 print_stats(1, "Mark Stack Scanning", mark_stack_scan_time);
ysr@777 1718 print_stats(1, "Scan-Only Scanning", scan_only_time);
ysr@777 1719 print_stats(1, "Scan RS", scan_rs_time);
ysr@777 1720 print_stats(1, "Object Copying", obj_copy_time);
ysr@777 1721 }
ysr@777 1722 }
johnc@1325 1723 #ifndef PRODUCT
johnc@1325 1724 print_stats(1, "Cur Clear CC", _cur_clear_cc_time_ms);
johnc@1325 1725 print_stats(1, "Cum Clear CC", _cum_clear_cc_time_ms);
johnc@1325 1726 print_stats(1, "Min Clear CC", _min_clear_cc_time_ms);
johnc@1325 1727 print_stats(1, "Max Clear CC", _max_clear_cc_time_ms);
johnc@1325 1728 if (_num_cc_clears > 0) {
johnc@1325 1729 print_stats(1, "Avg Clear CC", _cum_clear_cc_time_ms / ((double)_num_cc_clears));
johnc@1325 1730 }
johnc@1325 1731 #endif
ysr@777 1732 print_stats(1, "Other", other_time_ms);
ysr@777 1733 for (int i = 0; i < _aux_num; ++i) {
ysr@777 1734 if (_cur_aux_times_set[i]) {
ysr@777 1735 char buffer[96];
ysr@777 1736 sprintf(buffer, "Aux%d", i);
ysr@777 1737 print_stats(1, buffer, _cur_aux_times_ms[i]);
ysr@777 1738 }
ysr@777 1739 }
ysr@777 1740 }
ysr@777 1741 if (PrintGCDetails)
ysr@777 1742 gclog_or_tty->print(" [");
ysr@777 1743 if (PrintGC || PrintGCDetails)
ysr@777 1744 _g1->print_size_transition(gclog_or_tty,
ysr@777 1745 _cur_collection_pause_used_at_start_bytes,
ysr@777 1746 _g1->used(), _g1->capacity());
ysr@777 1747 if (PrintGCDetails)
ysr@777 1748 gclog_or_tty->print_cr("]");
ysr@777 1749
ysr@777 1750 _all_pause_times_ms->add(elapsed_ms);
tonyp@1083 1751 if (update_stats) {
tonyp@1083 1752 summary->record_total_time_ms(elapsed_ms);
tonyp@1083 1753 summary->record_other_time_ms(other_time_ms);
tonyp@1083 1754 }
ysr@777 1755 for (int i = 0; i < _aux_num; ++i)
ysr@777 1756 if (_cur_aux_times_set[i])
ysr@777 1757 _all_aux_times_ms[i].add(_cur_aux_times_ms[i]);
ysr@777 1758
ysr@777 1759 // Reset marks-between-pauses counter.
ysr@777 1760 _n_marks_since_last_pause = 0;
ysr@777 1761
ysr@777 1762 // Update the efficiency-since-mark vars.
ysr@777 1763 double proc_ms = elapsed_ms * (double) _parallel_gc_threads;
ysr@777 1764 if (elapsed_ms < MIN_TIMER_GRANULARITY) {
ysr@777 1765 // This usually happens due to the timer not having the required
ysr@777 1766 // granularity. Some Linuxes are the usual culprits.
ysr@777 1767 // We'll just set it to something (arbitrarily) small.
ysr@777 1768 proc_ms = 1.0;
ysr@777 1769 }
ysr@777 1770 double cur_efficiency = (double) freed_bytes / proc_ms;
ysr@777 1771
ysr@777 1772 bool new_in_marking_window = _in_marking_window;
ysr@777 1773 bool new_in_marking_window_im = false;
tonyp@1794 1774 if (during_initial_mark_pause()) {
ysr@777 1775 new_in_marking_window = true;
ysr@777 1776 new_in_marking_window_im = true;
ysr@777 1777 }
ysr@777 1778
ysr@777 1779 if (in_young_gc_mode()) {
ysr@777 1780 if (_last_full_young_gc) {
ysr@777 1781 set_full_young_gcs(false);
ysr@777 1782 _last_full_young_gc = false;
ysr@777 1783 }
ysr@777 1784
ysr@777 1785 if ( !_last_young_gc_full ) {
ysr@777 1786 if ( _should_revert_to_full_young_gcs ||
ysr@777 1787 _known_garbage_ratio < 0.05 ||
ysr@777 1788 (adaptive_young_list_length() &&
ysr@777 1789 (get_gc_eff_factor() * cur_efficiency < predict_young_gc_eff())) ) {
ysr@777 1790 set_full_young_gcs(true);
ysr@777 1791 }
ysr@777 1792 }
ysr@777 1793 _should_revert_to_full_young_gcs = false;
ysr@777 1794
ysr@777 1795 if (_last_young_gc_full && !_during_marking)
ysr@777 1796 _young_gc_eff_seq->add(cur_efficiency);
ysr@777 1797 }
ysr@777 1798
ysr@777 1799 _short_lived_surv_rate_group->start_adding_regions();
ysr@777 1800 // do that for any other surv rate groupsx
ysr@777 1801
ysr@777 1802 // <NEW PREDICTION>
ysr@777 1803
apetrusenko@1112 1804 if (update_stats) {
ysr@777 1805 double pause_time_ms = elapsed_ms;
ysr@777 1806
ysr@777 1807 size_t diff = 0;
ysr@777 1808 if (_max_pending_cards >= _pending_cards)
ysr@777 1809 diff = _max_pending_cards - _pending_cards;
ysr@777 1810 _pending_card_diff_seq->add((double) diff);
ysr@777 1811
ysr@777 1812 double cost_per_card_ms = 0.0;
ysr@777 1813 if (_pending_cards > 0) {
ysr@777 1814 cost_per_card_ms = update_rs_time / (double) _pending_cards;
ysr@777 1815 _cost_per_card_ms_seq->add(cost_per_card_ms);
ysr@777 1816 }
ysr@777 1817
ysr@777 1818 double cost_per_scan_only_region_ms = 0.0;
ysr@777 1819 if (scan_only_regions_scanned > 0.0) {
ysr@777 1820 cost_per_scan_only_region_ms =
ysr@777 1821 scan_only_time / scan_only_regions_scanned;
ysr@777 1822 if (_in_marking_window_im)
ysr@777 1823 _cost_per_scan_only_region_ms_during_cm_seq->add(cost_per_scan_only_region_ms);
ysr@777 1824 else
ysr@777 1825 _cost_per_scan_only_region_ms_seq->add(cost_per_scan_only_region_ms);
ysr@777 1826 }
ysr@777 1827
ysr@777 1828 size_t cards_scanned = _g1->cards_scanned();
ysr@777 1829
ysr@777 1830 double cost_per_entry_ms = 0.0;
ysr@777 1831 if (cards_scanned > 10) {
ysr@777 1832 cost_per_entry_ms = scan_rs_time / (double) cards_scanned;
ysr@777 1833 if (_last_young_gc_full)
ysr@777 1834 _cost_per_entry_ms_seq->add(cost_per_entry_ms);
ysr@777 1835 else
ysr@777 1836 _partially_young_cost_per_entry_ms_seq->add(cost_per_entry_ms);
ysr@777 1837 }
ysr@777 1838
ysr@777 1839 if (_max_rs_lengths > 0) {
ysr@777 1840 double cards_per_entry_ratio =
ysr@777 1841 (double) cards_scanned / (double) _max_rs_lengths;
ysr@777 1842 if (_last_young_gc_full)
ysr@777 1843 _fully_young_cards_per_entry_ratio_seq->add(cards_per_entry_ratio);
ysr@777 1844 else
ysr@777 1845 _partially_young_cards_per_entry_ratio_seq->add(cards_per_entry_ratio);
ysr@777 1846 }
ysr@777 1847
ysr@777 1848 size_t rs_length_diff = _max_rs_lengths - _recorded_rs_lengths;
ysr@777 1849 if (rs_length_diff >= 0)
ysr@777 1850 _rs_length_diff_seq->add((double) rs_length_diff);
ysr@777 1851
ysr@777 1852 size_t copied_bytes = surviving_bytes;
ysr@777 1853 double cost_per_byte_ms = 0.0;
ysr@777 1854 if (copied_bytes > 0) {
ysr@777 1855 cost_per_byte_ms = obj_copy_time / (double) copied_bytes;
ysr@777 1856 if (_in_marking_window)
ysr@777 1857 _cost_per_byte_ms_during_cm_seq->add(cost_per_byte_ms);
ysr@777 1858 else
ysr@777 1859 _cost_per_byte_ms_seq->add(cost_per_byte_ms);
ysr@777 1860 }
ysr@777 1861
ysr@777 1862 double all_other_time_ms = pause_time_ms -
ysr@777 1863 (update_rs_time + scan_only_time + scan_rs_time + obj_copy_time +
ysr@777 1864 _mark_closure_time_ms + termination_time);
ysr@777 1865
ysr@777 1866 double young_other_time_ms = 0.0;
ysr@777 1867 if (_recorded_young_regions > 0) {
ysr@777 1868 young_other_time_ms =
ysr@777 1869 _recorded_young_cset_choice_time_ms +
ysr@777 1870 _recorded_young_free_cset_time_ms;
ysr@777 1871 _young_other_cost_per_region_ms_seq->add(young_other_time_ms /
ysr@777 1872 (double) _recorded_young_regions);
ysr@777 1873 }
ysr@777 1874 double non_young_other_time_ms = 0.0;
ysr@777 1875 if (_recorded_non_young_regions > 0) {
ysr@777 1876 non_young_other_time_ms =
ysr@777 1877 _recorded_non_young_cset_choice_time_ms +
ysr@777 1878 _recorded_non_young_free_cset_time_ms;
ysr@777 1879
ysr@777 1880 _non_young_other_cost_per_region_ms_seq->add(non_young_other_time_ms /
ysr@777 1881 (double) _recorded_non_young_regions);
ysr@777 1882 }
ysr@777 1883
ysr@777 1884 double constant_other_time_ms = all_other_time_ms -
ysr@777 1885 (young_other_time_ms + non_young_other_time_ms);
ysr@777 1886 _constant_other_time_ms_seq->add(constant_other_time_ms);
ysr@777 1887
ysr@777 1888 double survival_ratio = 0.0;
ysr@777 1889 if (_bytes_in_collection_set_before_gc > 0) {
ysr@777 1890 survival_ratio = (double) bytes_in_to_space_during_gc() /
ysr@777 1891 (double) _bytes_in_collection_set_before_gc;
ysr@777 1892 }
ysr@777 1893
ysr@777 1894 _pending_cards_seq->add((double) _pending_cards);
ysr@777 1895 _scanned_cards_seq->add((double) cards_scanned);
ysr@777 1896 _rs_lengths_seq->add((double) _max_rs_lengths);
ysr@777 1897
ysr@777 1898 double expensive_region_limit_ms =
johnc@1186 1899 (double) MaxGCPauseMillis - predict_constant_other_time_ms();
ysr@777 1900 if (expensive_region_limit_ms < 0.0) {
ysr@777 1901 // this means that the other time was predicted to be longer than
ysr@777 1902 // than the max pause time
johnc@1186 1903 expensive_region_limit_ms = (double) MaxGCPauseMillis;
ysr@777 1904 }
ysr@777 1905 _expensive_region_limit_ms = expensive_region_limit_ms;
ysr@777 1906
ysr@777 1907 if (PREDICTIONS_VERBOSE) {
ysr@777 1908 gclog_or_tty->print_cr("");
ysr@777 1909 gclog_or_tty->print_cr("PREDICTIONS %1.4lf %d "
ysr@777 1910 "REGIONS %d %d %d %d "
ysr@777 1911 "PENDING_CARDS %d %d "
ysr@777 1912 "CARDS_SCANNED %d %d "
ysr@777 1913 "RS_LENGTHS %d %d "
ysr@777 1914 "SCAN_ONLY_SCAN %1.6lf %1.6lf "
ysr@777 1915 "RS_UPDATE %1.6lf %1.6lf RS_SCAN %1.6lf %1.6lf "
ysr@777 1916 "SURVIVAL_RATIO %1.6lf %1.6lf "
ysr@777 1917 "OBJECT_COPY %1.6lf %1.6lf OTHER_CONSTANT %1.6lf %1.6lf "
ysr@777 1918 "OTHER_YOUNG %1.6lf %1.6lf "
ysr@777 1919 "OTHER_NON_YOUNG %1.6lf %1.6lf "
ysr@777 1920 "VTIME_DIFF %1.6lf TERMINATION %1.6lf "
ysr@777 1921 "ELAPSED %1.6lf %1.6lf ",
ysr@777 1922 _cur_collection_start_sec,
ysr@777 1923 (!_last_young_gc_full) ? 2 :
ysr@777 1924 (last_pause_included_initial_mark) ? 1 : 0,
ysr@777 1925 _recorded_region_num,
ysr@777 1926 _recorded_young_regions,
ysr@777 1927 _recorded_scan_only_regions,
ysr@777 1928 _recorded_non_young_regions,
ysr@777 1929 _predicted_pending_cards, _pending_cards,
ysr@777 1930 _predicted_cards_scanned, cards_scanned,
ysr@777 1931 _predicted_rs_lengths, _max_rs_lengths,
ysr@777 1932 _predicted_scan_only_scan_time_ms, scan_only_time,
ysr@777 1933 _predicted_rs_update_time_ms, update_rs_time,
ysr@777 1934 _predicted_rs_scan_time_ms, scan_rs_time,
ysr@777 1935 _predicted_survival_ratio, survival_ratio,
ysr@777 1936 _predicted_object_copy_time_ms, obj_copy_time,
ysr@777 1937 _predicted_constant_other_time_ms, constant_other_time_ms,
ysr@777 1938 _predicted_young_other_time_ms, young_other_time_ms,
ysr@777 1939 _predicted_non_young_other_time_ms,
ysr@777 1940 non_young_other_time_ms,
ysr@777 1941 _vtime_diff_ms, termination_time,
ysr@777 1942 _predicted_pause_time_ms, elapsed_ms);
ysr@777 1943 }
ysr@777 1944
ysr@777 1945 if (G1PolicyVerbose > 0) {
ysr@777 1946 gclog_or_tty->print_cr("Pause Time, predicted: %1.4lfms (predicted %s), actual: %1.4lfms",
ysr@777 1947 _predicted_pause_time_ms,
ysr@777 1948 (_within_target) ? "within" : "outside",
ysr@777 1949 elapsed_ms);
ysr@777 1950 }
ysr@777 1951
ysr@777 1952 }
ysr@777 1953
ysr@777 1954 _in_marking_window = new_in_marking_window;
ysr@777 1955 _in_marking_window_im = new_in_marking_window_im;
ysr@777 1956 _free_regions_at_end_of_collection = _g1->free_regions();
ysr@777 1957 _scan_only_regions_at_end_of_collection = _g1->young_list_length();
ysr@777 1958 calculate_young_list_min_length();
ysr@777 1959 calculate_young_list_target_config();
ysr@777 1960
iveresov@1546 1961 // Note that _mmu_tracker->max_gc_time() returns the time in seconds.
tonyp@1717 1962 double update_rs_time_goal_ms = _mmu_tracker->max_gc_time() * MILLIUNITS * G1RSetUpdatingPauseTimePercent / 100.0;
iveresov@1546 1963 adjust_concurrent_refinement(update_rs_time, update_rs_processed_buffers, update_rs_time_goal_ms);
iveresov@1546 1964
ysr@777 1965 // </NEW PREDICTION>
ysr@777 1966
ysr@777 1967 _target_pause_time_ms = -1.0;
ysr@777 1968 }
ysr@777 1969
ysr@777 1970 // <NEW PREDICTION>
ysr@777 1971
iveresov@1546 1972 void G1CollectorPolicy::adjust_concurrent_refinement(double update_rs_time,
iveresov@1546 1973 double update_rs_processed_buffers,
iveresov@1546 1974 double goal_ms) {
iveresov@1546 1975 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set();
iveresov@1546 1976 ConcurrentG1Refine *cg1r = G1CollectedHeap::heap()->concurrent_g1_refine();
iveresov@1546 1977
tonyp@1717 1978 if (G1UseAdaptiveConcRefinement) {
iveresov@1546 1979 const int k_gy = 3, k_gr = 6;
iveresov@1546 1980 const double inc_k = 1.1, dec_k = 0.9;
iveresov@1546 1981
iveresov@1546 1982 int g = cg1r->green_zone();
iveresov@1546 1983 if (update_rs_time > goal_ms) {
iveresov@1546 1984 g = (int)(g * dec_k); // Can become 0, that's OK. That would mean a mutator-only processing.
iveresov@1546 1985 } else {
iveresov@1546 1986 if (update_rs_time < goal_ms && update_rs_processed_buffers > g) {
iveresov@1546 1987 g = (int)MAX2(g * inc_k, g + 1.0);
iveresov@1546 1988 }
iveresov@1546 1989 }
iveresov@1546 1990 // Change the refinement threads params
iveresov@1546 1991 cg1r->set_green_zone(g);
iveresov@1546 1992 cg1r->set_yellow_zone(g * k_gy);
iveresov@1546 1993 cg1r->set_red_zone(g * k_gr);
iveresov@1546 1994 cg1r->reinitialize_threads();
iveresov@1546 1995
iveresov@1546 1996 int processing_threshold_delta = MAX2((int)(cg1r->green_zone() * sigma()), 1);
iveresov@1546 1997 int processing_threshold = MIN2(cg1r->green_zone() + processing_threshold_delta,
iveresov@1546 1998 cg1r->yellow_zone());
iveresov@1546 1999 // Change the barrier params
iveresov@1546 2000 dcqs.set_process_completed_threshold(processing_threshold);
iveresov@1546 2001 dcqs.set_max_completed_queue(cg1r->red_zone());
iveresov@1546 2002 }
iveresov@1546 2003
iveresov@1546 2004 int curr_queue_size = dcqs.completed_buffers_num();
iveresov@1546 2005 if (curr_queue_size >= cg1r->yellow_zone()) {
iveresov@1546 2006 dcqs.set_completed_queue_padding(curr_queue_size);
iveresov@1546 2007 } else {
iveresov@1546 2008 dcqs.set_completed_queue_padding(0);
iveresov@1546 2009 }
iveresov@1546 2010 dcqs.notify_if_necessary();
iveresov@1546 2011 }
iveresov@1546 2012
ysr@777 2013 double
ysr@777 2014 G1CollectorPolicy::
ysr@777 2015 predict_young_collection_elapsed_time_ms(size_t adjustment) {
ysr@777 2016 guarantee( adjustment == 0 || adjustment == 1, "invariant" );
ysr@777 2017
ysr@777 2018 G1CollectedHeap* g1h = G1CollectedHeap::heap();
ysr@777 2019 size_t young_num = g1h->young_list_length();
ysr@777 2020 if (young_num == 0)
ysr@777 2021 return 0.0;
ysr@777 2022
ysr@777 2023 young_num += adjustment;
ysr@777 2024 size_t pending_cards = predict_pending_cards();
ysr@777 2025 size_t rs_lengths = g1h->young_list_sampled_rs_lengths() +
ysr@777 2026 predict_rs_length_diff();
ysr@777 2027 size_t card_num;
ysr@777 2028 if (full_young_gcs())
ysr@777 2029 card_num = predict_young_card_num(rs_lengths);
ysr@777 2030 else
ysr@777 2031 card_num = predict_non_young_card_num(rs_lengths);
ysr@777 2032 size_t young_byte_size = young_num * HeapRegion::GrainBytes;
ysr@777 2033 double accum_yg_surv_rate =
ysr@777 2034 _short_lived_surv_rate_group->accum_surv_rate(adjustment);
ysr@777 2035
ysr@777 2036 size_t bytes_to_copy =
ysr@777 2037 (size_t) (accum_yg_surv_rate * (double) HeapRegion::GrainBytes);
ysr@777 2038
ysr@777 2039 return
ysr@777 2040 predict_rs_update_time_ms(pending_cards) +
ysr@777 2041 predict_rs_scan_time_ms(card_num) +
ysr@777 2042 predict_object_copy_time_ms(bytes_to_copy) +
ysr@777 2043 predict_young_other_time_ms(young_num) +
ysr@777 2044 predict_constant_other_time_ms();
ysr@777 2045 }
ysr@777 2046
ysr@777 2047 double
ysr@777 2048 G1CollectorPolicy::predict_base_elapsed_time_ms(size_t pending_cards) {
ysr@777 2049 size_t rs_length = predict_rs_length_diff();
ysr@777 2050 size_t card_num;
ysr@777 2051 if (full_young_gcs())
ysr@777 2052 card_num = predict_young_card_num(rs_length);
ysr@777 2053 else
ysr@777 2054 card_num = predict_non_young_card_num(rs_length);
ysr@777 2055 return predict_base_elapsed_time_ms(pending_cards, card_num);
ysr@777 2056 }
ysr@777 2057
ysr@777 2058 double
ysr@777 2059 G1CollectorPolicy::predict_base_elapsed_time_ms(size_t pending_cards,
ysr@777 2060 size_t scanned_cards) {
ysr@777 2061 return
ysr@777 2062 predict_rs_update_time_ms(pending_cards) +
ysr@777 2063 predict_rs_scan_time_ms(scanned_cards) +
ysr@777 2064 predict_constant_other_time_ms();
ysr@777 2065 }
ysr@777 2066
ysr@777 2067 double
ysr@777 2068 G1CollectorPolicy::predict_region_elapsed_time_ms(HeapRegion* hr,
ysr@777 2069 bool young) {
ysr@777 2070 size_t rs_length = hr->rem_set()->occupied();
ysr@777 2071 size_t card_num;
ysr@777 2072 if (full_young_gcs())
ysr@777 2073 card_num = predict_young_card_num(rs_length);
ysr@777 2074 else
ysr@777 2075 card_num = predict_non_young_card_num(rs_length);
ysr@777 2076 size_t bytes_to_copy = predict_bytes_to_copy(hr);
ysr@777 2077
ysr@777 2078 double region_elapsed_time_ms =
ysr@777 2079 predict_rs_scan_time_ms(card_num) +
ysr@777 2080 predict_object_copy_time_ms(bytes_to_copy);
ysr@777 2081
ysr@777 2082 if (young)
ysr@777 2083 region_elapsed_time_ms += predict_young_other_time_ms(1);
ysr@777 2084 else
ysr@777 2085 region_elapsed_time_ms += predict_non_young_other_time_ms(1);
ysr@777 2086
ysr@777 2087 return region_elapsed_time_ms;
ysr@777 2088 }
ysr@777 2089
ysr@777 2090 size_t
ysr@777 2091 G1CollectorPolicy::predict_bytes_to_copy(HeapRegion* hr) {
ysr@777 2092 size_t bytes_to_copy;
ysr@777 2093 if (hr->is_marked())
ysr@777 2094 bytes_to_copy = hr->max_live_bytes();
ysr@777 2095 else {
ysr@777 2096 guarantee( hr->is_young() && hr->age_in_surv_rate_group() != -1,
ysr@777 2097 "invariant" );
ysr@777 2098 int age = hr->age_in_surv_rate_group();
apetrusenko@980 2099 double yg_surv_rate = predict_yg_surv_rate(age, hr->surv_rate_group());
ysr@777 2100 bytes_to_copy = (size_t) ((double) hr->used() * yg_surv_rate);
ysr@777 2101 }
ysr@777 2102
ysr@777 2103 return bytes_to_copy;
ysr@777 2104 }
ysr@777 2105
ysr@777 2106 void
ysr@777 2107 G1CollectorPolicy::start_recording_regions() {
ysr@777 2108 _recorded_rs_lengths = 0;
ysr@777 2109 _recorded_scan_only_regions = 0;
ysr@777 2110 _recorded_young_regions = 0;
ysr@777 2111 _recorded_non_young_regions = 0;
ysr@777 2112
ysr@777 2113 #if PREDICTIONS_VERBOSE
ysr@777 2114 _predicted_rs_lengths = 0;
ysr@777 2115 _predicted_cards_scanned = 0;
ysr@777 2116
ysr@777 2117 _recorded_marked_bytes = 0;
ysr@777 2118 _recorded_young_bytes = 0;
ysr@777 2119 _predicted_bytes_to_copy = 0;
ysr@777 2120 #endif // PREDICTIONS_VERBOSE
ysr@777 2121 }
ysr@777 2122
ysr@777 2123 void
ysr@777 2124 G1CollectorPolicy::record_cset_region(HeapRegion* hr, bool young) {
ysr@777 2125 if (young) {
ysr@777 2126 ++_recorded_young_regions;
ysr@777 2127 } else {
ysr@777 2128 ++_recorded_non_young_regions;
ysr@777 2129 }
ysr@777 2130 #if PREDICTIONS_VERBOSE
ysr@777 2131 if (young) {
apetrusenko@980 2132 _recorded_young_bytes += hr->used();
ysr@777 2133 } else {
ysr@777 2134 _recorded_marked_bytes += hr->max_live_bytes();
ysr@777 2135 }
ysr@777 2136 _predicted_bytes_to_copy += predict_bytes_to_copy(hr);
ysr@777 2137 #endif // PREDICTIONS_VERBOSE
ysr@777 2138
ysr@777 2139 size_t rs_length = hr->rem_set()->occupied();
ysr@777 2140 _recorded_rs_lengths += rs_length;
ysr@777 2141 }
ysr@777 2142
ysr@777 2143 void
ysr@777 2144 G1CollectorPolicy::record_scan_only_regions(size_t scan_only_length) {
ysr@777 2145 _recorded_scan_only_regions = scan_only_length;
ysr@777 2146 }
ysr@777 2147
ysr@777 2148 void
ysr@777 2149 G1CollectorPolicy::end_recording_regions() {
ysr@777 2150 #if PREDICTIONS_VERBOSE
ysr@777 2151 _predicted_pending_cards = predict_pending_cards();
ysr@777 2152 _predicted_rs_lengths = _recorded_rs_lengths + predict_rs_length_diff();
ysr@777 2153 if (full_young_gcs())
ysr@777 2154 _predicted_cards_scanned += predict_young_card_num(_predicted_rs_lengths);
ysr@777 2155 else
ysr@777 2156 _predicted_cards_scanned +=
ysr@777 2157 predict_non_young_card_num(_predicted_rs_lengths);
ysr@777 2158 _recorded_region_num = _recorded_young_regions + _recorded_non_young_regions;
ysr@777 2159
ysr@777 2160 _predicted_scan_only_scan_time_ms =
ysr@777 2161 predict_scan_only_time_ms(_recorded_scan_only_regions);
ysr@777 2162 _predicted_rs_update_time_ms =
ysr@777 2163 predict_rs_update_time_ms(_g1->pending_card_num());
ysr@777 2164 _predicted_rs_scan_time_ms =
ysr@777 2165 predict_rs_scan_time_ms(_predicted_cards_scanned);
ysr@777 2166 _predicted_object_copy_time_ms =
ysr@777 2167 predict_object_copy_time_ms(_predicted_bytes_to_copy);
ysr@777 2168 _predicted_constant_other_time_ms =
ysr@777 2169 predict_constant_other_time_ms();
ysr@777 2170 _predicted_young_other_time_ms =
ysr@777 2171 predict_young_other_time_ms(_recorded_young_regions);
ysr@777 2172 _predicted_non_young_other_time_ms =
ysr@777 2173 predict_non_young_other_time_ms(_recorded_non_young_regions);
ysr@777 2174
ysr@777 2175 _predicted_pause_time_ms =
ysr@777 2176 _predicted_scan_only_scan_time_ms +
ysr@777 2177 _predicted_rs_update_time_ms +
ysr@777 2178 _predicted_rs_scan_time_ms +
ysr@777 2179 _predicted_object_copy_time_ms +
ysr@777 2180 _predicted_constant_other_time_ms +
ysr@777 2181 _predicted_young_other_time_ms +
ysr@777 2182 _predicted_non_young_other_time_ms;
ysr@777 2183 #endif // PREDICTIONS_VERBOSE
ysr@777 2184 }
ysr@777 2185
ysr@777 2186 void G1CollectorPolicy::check_if_region_is_too_expensive(double
ysr@777 2187 predicted_time_ms) {
ysr@777 2188 // I don't think we need to do this when in young GC mode since
ysr@777 2189 // marking will be initiated next time we hit the soft limit anyway...
ysr@777 2190 if (predicted_time_ms > _expensive_region_limit_ms) {
ysr@777 2191 if (!in_young_gc_mode()) {
ysr@777 2192 set_full_young_gcs(true);
tonyp@1794 2193 // We might want to do something different here. However,
tonyp@1794 2194 // right now we don't support the non-generational G1 mode
tonyp@1794 2195 // (and in fact we are planning to remove the associated code,
tonyp@1794 2196 // see CR 6814390). So, let's leave it as is and this will be
tonyp@1794 2197 // removed some time in the future
tonyp@1794 2198 ShouldNotReachHere();
tonyp@1794 2199 set_during_initial_mark_pause();
ysr@777 2200 } else
ysr@777 2201 // no point in doing another partial one
ysr@777 2202 _should_revert_to_full_young_gcs = true;
ysr@777 2203 }
ysr@777 2204 }
ysr@777 2205
ysr@777 2206 // </NEW PREDICTION>
ysr@777 2207
ysr@777 2208
ysr@777 2209 void G1CollectorPolicy::update_recent_gc_times(double end_time_sec,
ysr@777 2210 double elapsed_ms) {
ysr@777 2211 _recent_gc_times_ms->add(elapsed_ms);
ysr@777 2212 _recent_prev_end_times_for_all_gcs_sec->add(end_time_sec);
ysr@777 2213 _prev_collection_pause_end_ms = end_time_sec * 1000.0;
ysr@777 2214 }
ysr@777 2215
ysr@777 2216 double G1CollectorPolicy::recent_avg_time_for_pauses_ms() {
johnc@1186 2217 if (_recent_pause_times_ms->num() == 0) return (double) MaxGCPauseMillis;
ysr@777 2218 else return _recent_pause_times_ms->avg();
ysr@777 2219 }
ysr@777 2220
ysr@777 2221 double G1CollectorPolicy::recent_avg_time_for_CH_strong_ms() {
ysr@777 2222 if (_recent_CH_strong_roots_times_ms->num() == 0)
johnc@1186 2223 return (double)MaxGCPauseMillis/3.0;
ysr@777 2224 else return _recent_CH_strong_roots_times_ms->avg();
ysr@777 2225 }
ysr@777 2226
ysr@777 2227 double G1CollectorPolicy::recent_avg_time_for_G1_strong_ms() {
ysr@777 2228 if (_recent_G1_strong_roots_times_ms->num() == 0)
johnc@1186 2229 return (double)MaxGCPauseMillis/3.0;
ysr@777 2230 else return _recent_G1_strong_roots_times_ms->avg();
ysr@777 2231 }
ysr@777 2232
ysr@777 2233 double G1CollectorPolicy::recent_avg_time_for_evac_ms() {
johnc@1186 2234 if (_recent_evac_times_ms->num() == 0) return (double)MaxGCPauseMillis/3.0;
ysr@777 2235 else return _recent_evac_times_ms->avg();
ysr@777 2236 }
ysr@777 2237
ysr@777 2238 int G1CollectorPolicy::number_of_recent_gcs() {
ysr@777 2239 assert(_recent_CH_strong_roots_times_ms->num() ==
ysr@777 2240 _recent_G1_strong_roots_times_ms->num(), "Sequence out of sync");
ysr@777 2241 assert(_recent_G1_strong_roots_times_ms->num() ==
ysr@777 2242 _recent_evac_times_ms->num(), "Sequence out of sync");
ysr@777 2243 assert(_recent_evac_times_ms->num() ==
ysr@777 2244 _recent_pause_times_ms->num(), "Sequence out of sync");
ysr@777 2245 assert(_recent_pause_times_ms->num() ==
ysr@777 2246 _recent_CS_bytes_used_before->num(), "Sequence out of sync");
ysr@777 2247 assert(_recent_CS_bytes_used_before->num() ==
ysr@777 2248 _recent_CS_bytes_surviving->num(), "Sequence out of sync");
ysr@777 2249 return _recent_pause_times_ms->num();
ysr@777 2250 }
ysr@777 2251
ysr@777 2252 double G1CollectorPolicy::recent_avg_survival_fraction() {
ysr@777 2253 return recent_avg_survival_fraction_work(_recent_CS_bytes_surviving,
ysr@777 2254 _recent_CS_bytes_used_before);
ysr@777 2255 }
ysr@777 2256
ysr@777 2257 double G1CollectorPolicy::last_survival_fraction() {
ysr@777 2258 return last_survival_fraction_work(_recent_CS_bytes_surviving,
ysr@777 2259 _recent_CS_bytes_used_before);
ysr@777 2260 }
ysr@777 2261
ysr@777 2262 double
ysr@777 2263 G1CollectorPolicy::recent_avg_survival_fraction_work(TruncatedSeq* surviving,
ysr@777 2264 TruncatedSeq* before) {
ysr@777 2265 assert(surviving->num() == before->num(), "Sequence out of sync");
ysr@777 2266 if (before->sum() > 0.0) {
ysr@777 2267 double recent_survival_rate = surviving->sum() / before->sum();
ysr@777 2268 // We exempt parallel collection from this check because Alloc Buffer
ysr@777 2269 // fragmentation can produce negative collections.
ysr@777 2270 // Further, we're now always doing parallel collection. But I'm still
ysr@777 2271 // leaving this here as a placeholder for a more precise assertion later.
ysr@777 2272 // (DLD, 10/05.)
ysr@777 2273 assert((true || ParallelGCThreads > 0) ||
ysr@777 2274 _g1->evacuation_failed() ||
ysr@777 2275 recent_survival_rate <= 1.0, "Or bad frac");
ysr@777 2276 return recent_survival_rate;
ysr@777 2277 } else {
ysr@777 2278 return 1.0; // Be conservative.
ysr@777 2279 }
ysr@777 2280 }
ysr@777 2281
ysr@777 2282 double
ysr@777 2283 G1CollectorPolicy::last_survival_fraction_work(TruncatedSeq* surviving,
ysr@777 2284 TruncatedSeq* before) {
ysr@777 2285 assert(surviving->num() == before->num(), "Sequence out of sync");
ysr@777 2286 if (surviving->num() > 0 && before->last() > 0.0) {
ysr@777 2287 double last_survival_rate = surviving->last() / before->last();
ysr@777 2288 // We exempt parallel collection from this check because Alloc Buffer
ysr@777 2289 // fragmentation can produce negative collections.
ysr@777 2290 // Further, we're now always doing parallel collection. But I'm still
ysr@777 2291 // leaving this here as a placeholder for a more precise assertion later.
ysr@777 2292 // (DLD, 10/05.)
ysr@777 2293 assert((true || ParallelGCThreads > 0) ||
ysr@777 2294 last_survival_rate <= 1.0, "Or bad frac");
ysr@777 2295 return last_survival_rate;
ysr@777 2296 } else {
ysr@777 2297 return 1.0;
ysr@777 2298 }
ysr@777 2299 }
ysr@777 2300
ysr@777 2301 static const int survival_min_obs = 5;
ysr@777 2302 static double survival_min_obs_limits[] = { 0.9, 0.7, 0.5, 0.3, 0.1 };
ysr@777 2303 static const double min_survival_rate = 0.1;
ysr@777 2304
ysr@777 2305 double
ysr@777 2306 G1CollectorPolicy::conservative_avg_survival_fraction_work(double avg,
ysr@777 2307 double latest) {
ysr@777 2308 double res = avg;
ysr@777 2309 if (number_of_recent_gcs() < survival_min_obs) {
ysr@777 2310 res = MAX2(res, survival_min_obs_limits[number_of_recent_gcs()]);
ysr@777 2311 }
ysr@777 2312 res = MAX2(res, latest);
ysr@777 2313 res = MAX2(res, min_survival_rate);
ysr@777 2314 // In the parallel case, LAB fragmentation can produce "negative
ysr@777 2315 // collections"; so can evac failure. Cap at 1.0
ysr@777 2316 res = MIN2(res, 1.0);
ysr@777 2317 return res;
ysr@777 2318 }
ysr@777 2319
ysr@777 2320 size_t G1CollectorPolicy::expansion_amount() {
tonyp@1791 2321 if ((recent_avg_pause_time_ratio() * 100.0) > _gc_overhead_perc) {
johnc@1186 2322 // We will double the existing space, or take
johnc@1186 2323 // G1ExpandByPercentOfAvailable % of the available expansion
johnc@1186 2324 // space, whichever is smaller, bounded below by a minimum
johnc@1186 2325 // expansion (unless that's all that's left.)
ysr@777 2326 const size_t min_expand_bytes = 1*M;
ysr@777 2327 size_t reserved_bytes = _g1->g1_reserved_obj_bytes();
ysr@777 2328 size_t committed_bytes = _g1->capacity();
ysr@777 2329 size_t uncommitted_bytes = reserved_bytes - committed_bytes;
ysr@777 2330 size_t expand_bytes;
ysr@777 2331 size_t expand_bytes_via_pct =
johnc@1186 2332 uncommitted_bytes * G1ExpandByPercentOfAvailable / 100;
ysr@777 2333 expand_bytes = MIN2(expand_bytes_via_pct, committed_bytes);
ysr@777 2334 expand_bytes = MAX2(expand_bytes, min_expand_bytes);
ysr@777 2335 expand_bytes = MIN2(expand_bytes, uncommitted_bytes);
ysr@777 2336 if (G1PolicyVerbose > 1) {
ysr@777 2337 gclog_or_tty->print("Decided to expand: ratio = %5.2f, "
ysr@777 2338 "committed = %d%s, uncommited = %d%s, via pct = %d%s.\n"
ysr@777 2339 " Answer = %d.\n",
ysr@777 2340 recent_avg_pause_time_ratio(),
ysr@777 2341 byte_size_in_proper_unit(committed_bytes),
ysr@777 2342 proper_unit_for_byte_size(committed_bytes),
ysr@777 2343 byte_size_in_proper_unit(uncommitted_bytes),
ysr@777 2344 proper_unit_for_byte_size(uncommitted_bytes),
ysr@777 2345 byte_size_in_proper_unit(expand_bytes_via_pct),
ysr@777 2346 proper_unit_for_byte_size(expand_bytes_via_pct),
ysr@777 2347 byte_size_in_proper_unit(expand_bytes),
ysr@777 2348 proper_unit_for_byte_size(expand_bytes));
ysr@777 2349 }
ysr@777 2350 return expand_bytes;
ysr@777 2351 } else {
ysr@777 2352 return 0;
ysr@777 2353 }
ysr@777 2354 }
ysr@777 2355
ysr@777 2356 void G1CollectorPolicy::note_start_of_mark_thread() {
ysr@777 2357 _mark_thread_startup_sec = os::elapsedTime();
ysr@777 2358 }
ysr@777 2359
ysr@777 2360 class CountCSClosure: public HeapRegionClosure {
ysr@777 2361 G1CollectorPolicy* _g1_policy;
ysr@777 2362 public:
ysr@777 2363 CountCSClosure(G1CollectorPolicy* g1_policy) :
ysr@777 2364 _g1_policy(g1_policy) {}
ysr@777 2365 bool doHeapRegion(HeapRegion* r) {
ysr@777 2366 _g1_policy->_bytes_in_collection_set_before_gc += r->used();
ysr@777 2367 return false;
ysr@777 2368 }
ysr@777 2369 };
ysr@777 2370
ysr@777 2371 void G1CollectorPolicy::count_CS_bytes_used() {
ysr@777 2372 CountCSClosure cs_closure(this);
ysr@777 2373 _g1->collection_set_iterate(&cs_closure);
ysr@777 2374 }
ysr@777 2375
ysr@777 2376 static void print_indent(int level) {
ysr@777 2377 for (int j = 0; j < level+1; ++j)
ysr@777 2378 gclog_or_tty->print(" ");
ysr@777 2379 }
ysr@777 2380
ysr@777 2381 void G1CollectorPolicy::print_summary (int level,
ysr@777 2382 const char* str,
ysr@777 2383 NumberSeq* seq) const {
ysr@777 2384 double sum = seq->sum();
ysr@777 2385 print_indent(level);
ysr@777 2386 gclog_or_tty->print_cr("%-24s = %8.2lf s (avg = %8.2lf ms)",
ysr@777 2387 str, sum / 1000.0, seq->avg());
ysr@777 2388 }
ysr@777 2389
ysr@777 2390 void G1CollectorPolicy::print_summary_sd (int level,
ysr@777 2391 const char* str,
ysr@777 2392 NumberSeq* seq) const {
ysr@777 2393 print_summary(level, str, seq);
ysr@777 2394 print_indent(level + 5);
ysr@777 2395 gclog_or_tty->print_cr("(num = %5d, std dev = %8.2lf ms, max = %8.2lf ms)",
ysr@777 2396 seq->num(), seq->sd(), seq->maximum());
ysr@777 2397 }
ysr@777 2398
ysr@777 2399 void G1CollectorPolicy::check_other_times(int level,
ysr@777 2400 NumberSeq* other_times_ms,
ysr@777 2401 NumberSeq* calc_other_times_ms) const {
ysr@777 2402 bool should_print = false;
ysr@777 2403
ysr@777 2404 double max_sum = MAX2(fabs(other_times_ms->sum()),
ysr@777 2405 fabs(calc_other_times_ms->sum()));
ysr@777 2406 double min_sum = MIN2(fabs(other_times_ms->sum()),
ysr@777 2407 fabs(calc_other_times_ms->sum()));
ysr@777 2408 double sum_ratio = max_sum / min_sum;
ysr@777 2409 if (sum_ratio > 1.1) {
ysr@777 2410 should_print = true;
ysr@777 2411 print_indent(level + 1);
ysr@777 2412 gclog_or_tty->print_cr("## CALCULATED OTHER SUM DOESN'T MATCH RECORDED ###");
ysr@777 2413 }
ysr@777 2414
ysr@777 2415 double max_avg = MAX2(fabs(other_times_ms->avg()),
ysr@777 2416 fabs(calc_other_times_ms->avg()));
ysr@777 2417 double min_avg = MIN2(fabs(other_times_ms->avg()),
ysr@777 2418 fabs(calc_other_times_ms->avg()));
ysr@777 2419 double avg_ratio = max_avg / min_avg;
ysr@777 2420 if (avg_ratio > 1.1) {
ysr@777 2421 should_print = true;
ysr@777 2422 print_indent(level + 1);
ysr@777 2423 gclog_or_tty->print_cr("## CALCULATED OTHER AVG DOESN'T MATCH RECORDED ###");
ysr@777 2424 }
ysr@777 2425
ysr@777 2426 if (other_times_ms->sum() < -0.01) {
ysr@777 2427 print_indent(level + 1);
ysr@777 2428 gclog_or_tty->print_cr("## RECORDED OTHER SUM IS NEGATIVE ###");
ysr@777 2429 }
ysr@777 2430
ysr@777 2431 if (other_times_ms->avg() < -0.01) {
ysr@777 2432 print_indent(level + 1);
ysr@777 2433 gclog_or_tty->print_cr("## RECORDED OTHER AVG IS NEGATIVE ###");
ysr@777 2434 }
ysr@777 2435
ysr@777 2436 if (calc_other_times_ms->sum() < -0.01) {
ysr@777 2437 should_print = true;
ysr@777 2438 print_indent(level + 1);
ysr@777 2439 gclog_or_tty->print_cr("## CALCULATED OTHER SUM IS NEGATIVE ###");
ysr@777 2440 }
ysr@777 2441
ysr@777 2442 if (calc_other_times_ms->avg() < -0.01) {
ysr@777 2443 should_print = true;
ysr@777 2444 print_indent(level + 1);
ysr@777 2445 gclog_or_tty->print_cr("## CALCULATED OTHER AVG IS NEGATIVE ###");
ysr@777 2446 }
ysr@777 2447
ysr@777 2448 if (should_print)
ysr@777 2449 print_summary(level, "Other(Calc)", calc_other_times_ms);
ysr@777 2450 }
ysr@777 2451
ysr@777 2452 void G1CollectorPolicy::print_summary(PauseSummary* summary) const {
ysr@777 2453 bool parallel = ParallelGCThreads > 0;
ysr@777 2454 MainBodySummary* body_summary = summary->main_body_summary();
ysr@777 2455 if (summary->get_total_seq()->num() > 0) {
apetrusenko@1112 2456 print_summary_sd(0, "Evacuation Pauses", summary->get_total_seq());
ysr@777 2457 if (body_summary != NULL) {
ysr@777 2458 print_summary(1, "SATB Drain", body_summary->get_satb_drain_seq());
ysr@777 2459 if (parallel) {
ysr@777 2460 print_summary(1, "Parallel Time", body_summary->get_parallel_seq());
ysr@777 2461 print_summary(2, "Update RS", body_summary->get_update_rs_seq());
ysr@777 2462 print_summary(2, "Ext Root Scanning",
ysr@777 2463 body_summary->get_ext_root_scan_seq());
ysr@777 2464 print_summary(2, "Mark Stack Scanning",
ysr@777 2465 body_summary->get_mark_stack_scan_seq());
ysr@777 2466 print_summary(2, "Scan-Only Scanning",
ysr@777 2467 body_summary->get_scan_only_seq());
ysr@777 2468 print_summary(2, "Scan RS", body_summary->get_scan_rs_seq());
ysr@777 2469 print_summary(2, "Object Copy", body_summary->get_obj_copy_seq());
ysr@777 2470 print_summary(2, "Termination", body_summary->get_termination_seq());
ysr@777 2471 print_summary(2, "Other", body_summary->get_parallel_other_seq());
ysr@777 2472 {
ysr@777 2473 NumberSeq* other_parts[] = {
ysr@777 2474 body_summary->get_update_rs_seq(),
ysr@777 2475 body_summary->get_ext_root_scan_seq(),
ysr@777 2476 body_summary->get_mark_stack_scan_seq(),
ysr@777 2477 body_summary->get_scan_only_seq(),
ysr@777 2478 body_summary->get_scan_rs_seq(),
ysr@777 2479 body_summary->get_obj_copy_seq(),
ysr@777 2480 body_summary->get_termination_seq()
ysr@777 2481 };
ysr@777 2482 NumberSeq calc_other_times_ms(body_summary->get_parallel_seq(),
ysr@777 2483 7, other_parts);
ysr@777 2484 check_other_times(2, body_summary->get_parallel_other_seq(),
ysr@777 2485 &calc_other_times_ms);
ysr@777 2486 }
ysr@777 2487 print_summary(1, "Mark Closure", body_summary->get_mark_closure_seq());
ysr@777 2488 print_summary(1, "Clear CT", body_summary->get_clear_ct_seq());
ysr@777 2489 } else {
ysr@777 2490 print_summary(1, "Update RS", body_summary->get_update_rs_seq());
ysr@777 2491 print_summary(1, "Ext Root Scanning",
ysr@777 2492 body_summary->get_ext_root_scan_seq());
ysr@777 2493 print_summary(1, "Mark Stack Scanning",
ysr@777 2494 body_summary->get_mark_stack_scan_seq());
ysr@777 2495 print_summary(1, "Scan-Only Scanning",
ysr@777 2496 body_summary->get_scan_only_seq());
ysr@777 2497 print_summary(1, "Scan RS", body_summary->get_scan_rs_seq());
ysr@777 2498 print_summary(1, "Object Copy", body_summary->get_obj_copy_seq());
ysr@777 2499 }
ysr@777 2500 }
ysr@777 2501 print_summary(1, "Other", summary->get_other_seq());
ysr@777 2502 {
ysr@777 2503 NumberSeq calc_other_times_ms;
ysr@777 2504 if (body_summary != NULL) {
ysr@777 2505 // not abandoned
ysr@777 2506 if (parallel) {
ysr@777 2507 // parallel
ysr@777 2508 NumberSeq* other_parts[] = {
ysr@777 2509 body_summary->get_satb_drain_seq(),
ysr@777 2510 body_summary->get_parallel_seq(),
ysr@777 2511 body_summary->get_clear_ct_seq()
ysr@777 2512 };
apetrusenko@1112 2513 calc_other_times_ms = NumberSeq(summary->get_total_seq(),
apetrusenko@1112 2514 3, other_parts);
ysr@777 2515 } else {
ysr@777 2516 // serial
ysr@777 2517 NumberSeq* other_parts[] = {
ysr@777 2518 body_summary->get_satb_drain_seq(),
ysr@777 2519 body_summary->get_update_rs_seq(),
ysr@777 2520 body_summary->get_ext_root_scan_seq(),
ysr@777 2521 body_summary->get_mark_stack_scan_seq(),
ysr@777 2522 body_summary->get_scan_only_seq(),
ysr@777 2523 body_summary->get_scan_rs_seq(),
ysr@777 2524 body_summary->get_obj_copy_seq()
ysr@777 2525 };
ysr@777 2526 calc_other_times_ms = NumberSeq(summary->get_total_seq(),
apetrusenko@1112 2527 7, other_parts);
ysr@777 2528 }
ysr@777 2529 } else {
ysr@777 2530 // abandoned
apetrusenko@1112 2531 calc_other_times_ms = NumberSeq();
ysr@777 2532 }
ysr@777 2533 check_other_times(1, summary->get_other_seq(), &calc_other_times_ms);
ysr@777 2534 }
ysr@777 2535 } else {
ysr@777 2536 print_indent(0);
ysr@777 2537 gclog_or_tty->print_cr("none");
ysr@777 2538 }
ysr@777 2539 gclog_or_tty->print_cr("");
ysr@777 2540 }
ysr@777 2541
ysr@777 2542 void
apetrusenko@1112 2543 G1CollectorPolicy::print_abandoned_summary(PauseSummary* summary) const {
ysr@777 2544 bool printed = false;
apetrusenko@1112 2545 if (summary->get_total_seq()->num() > 0) {
ysr@777 2546 printed = true;
apetrusenko@1112 2547 print_summary(summary);
ysr@777 2548 }
ysr@777 2549 if (!printed) {
ysr@777 2550 print_indent(0);
ysr@777 2551 gclog_or_tty->print_cr("none");
ysr@777 2552 gclog_or_tty->print_cr("");
ysr@777 2553 }
ysr@777 2554 }
ysr@777 2555
ysr@777 2556 void G1CollectorPolicy::print_tracing_info() const {
ysr@777 2557 if (TraceGen0Time) {
ysr@777 2558 gclog_or_tty->print_cr("ALL PAUSES");
ysr@777 2559 print_summary_sd(0, "Total", _all_pause_times_ms);
ysr@777 2560 gclog_or_tty->print_cr("");
ysr@777 2561 gclog_or_tty->print_cr("");
ysr@777 2562 gclog_or_tty->print_cr(" Full Young GC Pauses: %8d", _full_young_pause_num);
ysr@777 2563 gclog_or_tty->print_cr(" Partial Young GC Pauses: %8d", _partial_young_pause_num);
ysr@777 2564 gclog_or_tty->print_cr("");
ysr@777 2565
apetrusenko@1112 2566 gclog_or_tty->print_cr("EVACUATION PAUSES");
apetrusenko@1112 2567 print_summary(_summary);
ysr@777 2568
ysr@777 2569 gclog_or_tty->print_cr("ABANDONED PAUSES");
apetrusenko@1112 2570 print_abandoned_summary(_abandoned_summary);
ysr@777 2571
ysr@777 2572 gclog_or_tty->print_cr("MISC");
ysr@777 2573 print_summary_sd(0, "Stop World", _all_stop_world_times_ms);
ysr@777 2574 print_summary_sd(0, "Yields", _all_yield_times_ms);
ysr@777 2575 for (int i = 0; i < _aux_num; ++i) {
ysr@777 2576 if (_all_aux_times_ms[i].num() > 0) {
ysr@777 2577 char buffer[96];
ysr@777 2578 sprintf(buffer, "Aux%d", i);
ysr@777 2579 print_summary_sd(0, buffer, &_all_aux_times_ms[i]);
ysr@777 2580 }
ysr@777 2581 }
ysr@777 2582
ysr@777 2583 size_t all_region_num = _region_num_young + _region_num_tenured;
ysr@777 2584 gclog_or_tty->print_cr(" New Regions %8d, Young %8d (%6.2lf%%), "
ysr@777 2585 "Tenured %8d (%6.2lf%%)",
ysr@777 2586 all_region_num,
ysr@777 2587 _region_num_young,
ysr@777 2588 (double) _region_num_young / (double) all_region_num * 100.0,
ysr@777 2589 _region_num_tenured,
ysr@777 2590 (double) _region_num_tenured / (double) all_region_num * 100.0);
ysr@777 2591 }
ysr@777 2592 if (TraceGen1Time) {
ysr@777 2593 if (_all_full_gc_times_ms->num() > 0) {
ysr@777 2594 gclog_or_tty->print("\n%4d full_gcs: total time = %8.2f s",
ysr@777 2595 _all_full_gc_times_ms->num(),
ysr@777 2596 _all_full_gc_times_ms->sum() / 1000.0);
ysr@777 2597 gclog_or_tty->print_cr(" (avg = %8.2fms).", _all_full_gc_times_ms->avg());
ysr@777 2598 gclog_or_tty->print_cr(" [std. dev = %8.2f ms, max = %8.2f ms]",
ysr@777 2599 _all_full_gc_times_ms->sd(),
ysr@777 2600 _all_full_gc_times_ms->maximum());
ysr@777 2601 }
ysr@777 2602 }
ysr@777 2603 }
ysr@777 2604
ysr@777 2605 void G1CollectorPolicy::print_yg_surv_rate_info() const {
ysr@777 2606 #ifndef PRODUCT
ysr@777 2607 _short_lived_surv_rate_group->print_surv_rate_summary();
ysr@777 2608 // add this call for any other surv rate groups
ysr@777 2609 #endif // PRODUCT
ysr@777 2610 }
ysr@777 2611
ysr@777 2612 bool
ysr@777 2613 G1CollectorPolicy::should_add_next_region_to_young_list() {
ysr@777 2614 assert(in_young_gc_mode(), "should be in young GC mode");
ysr@777 2615 bool ret;
ysr@777 2616 size_t young_list_length = _g1->young_list_length();
apetrusenko@980 2617 size_t young_list_max_length = _young_list_target_length;
apetrusenko@980 2618 if (G1FixedEdenSize) {
apetrusenko@980 2619 young_list_max_length -= _max_survivor_regions;
apetrusenko@980 2620 }
apetrusenko@980 2621 if (young_list_length < young_list_max_length) {
ysr@777 2622 ret = true;
ysr@777 2623 ++_region_num_young;
ysr@777 2624 } else {
ysr@777 2625 ret = false;
ysr@777 2626 ++_region_num_tenured;
ysr@777 2627 }
ysr@777 2628
ysr@777 2629 return ret;
ysr@777 2630 }
ysr@777 2631
ysr@777 2632 #ifndef PRODUCT
ysr@777 2633 // for debugging, bit of a hack...
ysr@777 2634 static char*
ysr@777 2635 region_num_to_mbs(int length) {
ysr@777 2636 static char buffer[64];
ysr@777 2637 double bytes = (double) (length * HeapRegion::GrainBytes);
ysr@777 2638 double mbs = bytes / (double) (1024 * 1024);
ysr@777 2639 sprintf(buffer, "%7.2lfMB", mbs);
ysr@777 2640 return buffer;
ysr@777 2641 }
ysr@777 2642 #endif // PRODUCT
ysr@777 2643
apetrusenko@980 2644 size_t G1CollectorPolicy::max_regions(int purpose) {
ysr@777 2645 switch (purpose) {
ysr@777 2646 case GCAllocForSurvived:
apetrusenko@980 2647 return _max_survivor_regions;
ysr@777 2648 case GCAllocForTenured:
apetrusenko@980 2649 return REGIONS_UNLIMITED;
ysr@777 2650 default:
apetrusenko@980 2651 ShouldNotReachHere();
apetrusenko@980 2652 return REGIONS_UNLIMITED;
ysr@777 2653 };
ysr@777 2654 }
ysr@777 2655
apetrusenko@980 2656 // Calculates survivor space parameters.
apetrusenko@980 2657 void G1CollectorPolicy::calculate_survivors_policy()
apetrusenko@980 2658 {
apetrusenko@980 2659 if (G1FixedSurvivorSpaceSize == 0) {
apetrusenko@980 2660 _max_survivor_regions = _young_list_target_length / SurvivorRatio;
apetrusenko@980 2661 } else {
apetrusenko@982 2662 _max_survivor_regions = G1FixedSurvivorSpaceSize / HeapRegion::GrainBytes;
apetrusenko@980 2663 }
apetrusenko@980 2664
apetrusenko@980 2665 if (G1FixedTenuringThreshold) {
apetrusenko@980 2666 _tenuring_threshold = MaxTenuringThreshold;
apetrusenko@980 2667 } else {
apetrusenko@980 2668 _tenuring_threshold = _survivors_age_table.compute_tenuring_threshold(
apetrusenko@980 2669 HeapRegion::GrainWords * _max_survivor_regions);
apetrusenko@980 2670 }
apetrusenko@980 2671 }
apetrusenko@980 2672
ysr@777 2673 bool
ysr@777 2674 G1CollectorPolicy_BestRegionsFirst::should_do_collection_pause(size_t
ysr@777 2675 word_size) {
ysr@777 2676 assert(_g1->regions_accounted_for(), "Region leakage!");
ysr@777 2677 double max_pause_time_ms = _mmu_tracker->max_gc_time() * 1000.0;
ysr@777 2678
ysr@777 2679 size_t young_list_length = _g1->young_list_length();
apetrusenko@980 2680 size_t young_list_max_length = _young_list_target_length;
apetrusenko@980 2681 if (G1FixedEdenSize) {
apetrusenko@980 2682 young_list_max_length -= _max_survivor_regions;
apetrusenko@980 2683 }
apetrusenko@980 2684 bool reached_target_length = young_list_length >= young_list_max_length;
ysr@777 2685
ysr@777 2686 if (in_young_gc_mode()) {
ysr@777 2687 if (reached_target_length) {
ysr@777 2688 assert( young_list_length > 0 && _g1->young_list_length() > 0,
ysr@777 2689 "invariant" );
ysr@777 2690 _target_pause_time_ms = max_pause_time_ms;
ysr@777 2691 return true;
ysr@777 2692 }
ysr@777 2693 } else {
ysr@777 2694 guarantee( false, "should not reach here" );
ysr@777 2695 }
ysr@777 2696
ysr@777 2697 return false;
ysr@777 2698 }
ysr@777 2699
ysr@777 2700 #ifndef PRODUCT
ysr@777 2701 class HRSortIndexIsOKClosure: public HeapRegionClosure {
ysr@777 2702 CollectionSetChooser* _chooser;
ysr@777 2703 public:
ysr@777 2704 HRSortIndexIsOKClosure(CollectionSetChooser* chooser) :
ysr@777 2705 _chooser(chooser) {}
ysr@777 2706
ysr@777 2707 bool doHeapRegion(HeapRegion* r) {
ysr@777 2708 if (!r->continuesHumongous()) {
ysr@777 2709 assert(_chooser->regionProperlyOrdered(r), "Ought to be.");
ysr@777 2710 }
ysr@777 2711 return false;
ysr@777 2712 }
ysr@777 2713 };
ysr@777 2714
ysr@777 2715 bool G1CollectorPolicy_BestRegionsFirst::assertMarkedBytesDataOK() {
ysr@777 2716 HRSortIndexIsOKClosure cl(_collectionSetChooser);
ysr@777 2717 _g1->heap_region_iterate(&cl);
ysr@777 2718 return true;
ysr@777 2719 }
ysr@777 2720 #endif
ysr@777 2721
ysr@777 2722 void
tonyp@1794 2723 G1CollectorPolicy::decide_on_conc_mark_initiation() {
tonyp@1794 2724 // We are about to decide on whether this pause will be an
tonyp@1794 2725 // initial-mark pause.
tonyp@1794 2726
tonyp@1794 2727 // First, during_initial_mark_pause() should not be already set. We
tonyp@1794 2728 // will set it here if we have to. However, it should be cleared by
tonyp@1794 2729 // the end of the pause (it's only set for the duration of an
tonyp@1794 2730 // initial-mark pause).
tonyp@1794 2731 assert(!during_initial_mark_pause(), "pre-condition");
tonyp@1794 2732
tonyp@1794 2733 if (initiate_conc_mark_if_possible()) {
tonyp@1794 2734 // We had noticed on a previous pause that the heap occupancy has
tonyp@1794 2735 // gone over the initiating threshold and we should start a
tonyp@1794 2736 // concurrent marking cycle. So we might initiate one.
tonyp@1794 2737
tonyp@1794 2738 bool during_cycle = _g1->concurrent_mark()->cmThread()->during_cycle();
tonyp@1794 2739 if (!during_cycle) {
tonyp@1794 2740 // The concurrent marking thread is not "during a cycle", i.e.,
tonyp@1794 2741 // it has completed the last one. So we can go ahead and
tonyp@1794 2742 // initiate a new cycle.
tonyp@1794 2743
tonyp@1794 2744 set_during_initial_mark_pause();
tonyp@1794 2745
tonyp@1794 2746 // And we can now clear initiate_conc_mark_if_possible() as
tonyp@1794 2747 // we've already acted on it.
tonyp@1794 2748 clear_initiate_conc_mark_if_possible();
tonyp@1794 2749 } else {
tonyp@1794 2750 // The concurrent marking thread is still finishing up the
tonyp@1794 2751 // previous cycle. If we start one right now the two cycles
tonyp@1794 2752 // overlap. In particular, the concurrent marking thread might
tonyp@1794 2753 // be in the process of clearing the next marking bitmap (which
tonyp@1794 2754 // we will use for the next cycle if we start one). Starting a
tonyp@1794 2755 // cycle now will be bad given that parts of the marking
tonyp@1794 2756 // information might get cleared by the marking thread. And we
tonyp@1794 2757 // cannot wait for the marking thread to finish the cycle as it
tonyp@1794 2758 // periodically yields while clearing the next marking bitmap
tonyp@1794 2759 // and, if it's in a yield point, it's waiting for us to
tonyp@1794 2760 // finish. So, at this point we will not start a cycle and we'll
tonyp@1794 2761 // let the concurrent marking thread complete the last one.
tonyp@1794 2762 }
tonyp@1794 2763 }
tonyp@1794 2764 }
tonyp@1794 2765
tonyp@1794 2766 void
ysr@777 2767 G1CollectorPolicy_BestRegionsFirst::
ysr@777 2768 record_collection_pause_start(double start_time_sec, size_t start_used) {
ysr@777 2769 G1CollectorPolicy::record_collection_pause_start(start_time_sec, start_used);
ysr@777 2770 }
ysr@777 2771
ysr@777 2772 class NextNonCSElemFinder: public HeapRegionClosure {
ysr@777 2773 HeapRegion* _res;
ysr@777 2774 public:
ysr@777 2775 NextNonCSElemFinder(): _res(NULL) {}
ysr@777 2776 bool doHeapRegion(HeapRegion* r) {
ysr@777 2777 if (!r->in_collection_set()) {
ysr@777 2778 _res = r;
ysr@777 2779 return true;
ysr@777 2780 } else {
ysr@777 2781 return false;
ysr@777 2782 }
ysr@777 2783 }
ysr@777 2784 HeapRegion* res() { return _res; }
ysr@777 2785 };
ysr@777 2786
ysr@777 2787 class KnownGarbageClosure: public HeapRegionClosure {
ysr@777 2788 CollectionSetChooser* _hrSorted;
ysr@777 2789
ysr@777 2790 public:
ysr@777 2791 KnownGarbageClosure(CollectionSetChooser* hrSorted) :
ysr@777 2792 _hrSorted(hrSorted)
ysr@777 2793 {}
ysr@777 2794
ysr@777 2795 bool doHeapRegion(HeapRegion* r) {
ysr@777 2796 // We only include humongous regions in collection
ysr@777 2797 // sets when concurrent mark shows that their contained object is
ysr@777 2798 // unreachable.
ysr@777 2799
ysr@777 2800 // Do we have any marking information for this region?
ysr@777 2801 if (r->is_marked()) {
ysr@777 2802 // We don't include humongous regions in collection
ysr@777 2803 // sets because we collect them immediately at the end of a marking
ysr@777 2804 // cycle. We also don't include young regions because we *must*
ysr@777 2805 // include them in the next collection pause.
ysr@777 2806 if (!r->isHumongous() && !r->is_young()) {
ysr@777 2807 _hrSorted->addMarkedHeapRegion(r);
ysr@777 2808 }
ysr@777 2809 }
ysr@777 2810 return false;
ysr@777 2811 }
ysr@777 2812 };
ysr@777 2813
ysr@777 2814 class ParKnownGarbageHRClosure: public HeapRegionClosure {
ysr@777 2815 CollectionSetChooser* _hrSorted;
ysr@777 2816 jint _marked_regions_added;
ysr@777 2817 jint _chunk_size;
ysr@777 2818 jint _cur_chunk_idx;
ysr@777 2819 jint _cur_chunk_end; // Cur chunk [_cur_chunk_idx, _cur_chunk_end)
ysr@777 2820 int _worker;
ysr@777 2821 int _invokes;
ysr@777 2822
ysr@777 2823 void get_new_chunk() {
ysr@777 2824 _cur_chunk_idx = _hrSorted->getParMarkedHeapRegionChunk(_chunk_size);
ysr@777 2825 _cur_chunk_end = _cur_chunk_idx + _chunk_size;
ysr@777 2826 }
ysr@777 2827 void add_region(HeapRegion* r) {
ysr@777 2828 if (_cur_chunk_idx == _cur_chunk_end) {
ysr@777 2829 get_new_chunk();
ysr@777 2830 }
ysr@777 2831 assert(_cur_chunk_idx < _cur_chunk_end, "postcondition");
ysr@777 2832 _hrSorted->setMarkedHeapRegion(_cur_chunk_idx, r);
ysr@777 2833 _marked_regions_added++;
ysr@777 2834 _cur_chunk_idx++;
ysr@777 2835 }
ysr@777 2836
ysr@777 2837 public:
ysr@777 2838 ParKnownGarbageHRClosure(CollectionSetChooser* hrSorted,
ysr@777 2839 jint chunk_size,
ysr@777 2840 int worker) :
ysr@777 2841 _hrSorted(hrSorted), _chunk_size(chunk_size), _worker(worker),
ysr@777 2842 _marked_regions_added(0), _cur_chunk_idx(0), _cur_chunk_end(0),
ysr@777 2843 _invokes(0)
ysr@777 2844 {}
ysr@777 2845
ysr@777 2846 bool doHeapRegion(HeapRegion* r) {
ysr@777 2847 // We only include humongous regions in collection
ysr@777 2848 // sets when concurrent mark shows that their contained object is
ysr@777 2849 // unreachable.
ysr@777 2850 _invokes++;
ysr@777 2851
ysr@777 2852 // Do we have any marking information for this region?
ysr@777 2853 if (r->is_marked()) {
ysr@777 2854 // We don't include humongous regions in collection
ysr@777 2855 // sets because we collect them immediately at the end of a marking
ysr@777 2856 // cycle.
ysr@777 2857 // We also do not include young regions in collection sets
ysr@777 2858 if (!r->isHumongous() && !r->is_young()) {
ysr@777 2859 add_region(r);
ysr@777 2860 }
ysr@777 2861 }
ysr@777 2862 return false;
ysr@777 2863 }
ysr@777 2864 jint marked_regions_added() { return _marked_regions_added; }
ysr@777 2865 int invokes() { return _invokes; }
ysr@777 2866 };
ysr@777 2867
ysr@777 2868 class ParKnownGarbageTask: public AbstractGangTask {
ysr@777 2869 CollectionSetChooser* _hrSorted;
ysr@777 2870 jint _chunk_size;
ysr@777 2871 G1CollectedHeap* _g1;
ysr@777 2872 public:
ysr@777 2873 ParKnownGarbageTask(CollectionSetChooser* hrSorted, jint chunk_size) :
ysr@777 2874 AbstractGangTask("ParKnownGarbageTask"),
ysr@777 2875 _hrSorted(hrSorted), _chunk_size(chunk_size),
ysr@777 2876 _g1(G1CollectedHeap::heap())
ysr@777 2877 {}
ysr@777 2878
ysr@777 2879 void work(int i) {
ysr@777 2880 ParKnownGarbageHRClosure parKnownGarbageCl(_hrSorted, _chunk_size, i);
ysr@777 2881 // Back to zero for the claim value.
tonyp@790 2882 _g1->heap_region_par_iterate_chunked(&parKnownGarbageCl, i,
tonyp@790 2883 HeapRegion::InitialClaimValue);
ysr@777 2884 jint regions_added = parKnownGarbageCl.marked_regions_added();
ysr@777 2885 _hrSorted->incNumMarkedHeapRegions(regions_added);
ysr@777 2886 if (G1PrintParCleanupStats) {
ysr@777 2887 gclog_or_tty->print(" Thread %d called %d times, added %d regions to list.\n",
ysr@777 2888 i, parKnownGarbageCl.invokes(), regions_added);
ysr@777 2889 }
ysr@777 2890 }
ysr@777 2891 };
ysr@777 2892
ysr@777 2893 void
ysr@777 2894 G1CollectorPolicy_BestRegionsFirst::
ysr@777 2895 record_concurrent_mark_cleanup_end(size_t freed_bytes,
ysr@777 2896 size_t max_live_bytes) {
ysr@777 2897 double start;
ysr@777 2898 if (G1PrintParCleanupStats) start = os::elapsedTime();
ysr@777 2899 record_concurrent_mark_cleanup_end_work1(freed_bytes, max_live_bytes);
ysr@777 2900
ysr@777 2901 _collectionSetChooser->clearMarkedHeapRegions();
ysr@777 2902 double clear_marked_end;
ysr@777 2903 if (G1PrintParCleanupStats) {
ysr@777 2904 clear_marked_end = os::elapsedTime();
ysr@777 2905 gclog_or_tty->print_cr(" clear marked regions + work1: %8.3f ms.",
ysr@777 2906 (clear_marked_end - start)*1000.0);
ysr@777 2907 }
ysr@777 2908 if (ParallelGCThreads > 0) {
ysr@777 2909 const size_t OverpartitionFactor = 4;
ysr@777 2910 const size_t MinChunkSize = 8;
ysr@777 2911 const size_t ChunkSize =
ysr@777 2912 MAX2(_g1->n_regions() / (ParallelGCThreads * OverpartitionFactor),
ysr@777 2913 MinChunkSize);
ysr@777 2914 _collectionSetChooser->prepareForAddMarkedHeapRegionsPar(_g1->n_regions(),
ysr@777 2915 ChunkSize);
ysr@777 2916 ParKnownGarbageTask parKnownGarbageTask(_collectionSetChooser,
ysr@777 2917 (int) ChunkSize);
ysr@777 2918 _g1->workers()->run_task(&parKnownGarbageTask);
tonyp@790 2919
tonyp@790 2920 assert(_g1->check_heap_region_claim_values(HeapRegion::InitialClaimValue),
tonyp@790 2921 "sanity check");
ysr@777 2922 } else {
ysr@777 2923 KnownGarbageClosure knownGarbagecl(_collectionSetChooser);
ysr@777 2924 _g1->heap_region_iterate(&knownGarbagecl);
ysr@777 2925 }
ysr@777 2926 double known_garbage_end;
ysr@777 2927 if (G1PrintParCleanupStats) {
ysr@777 2928 known_garbage_end = os::elapsedTime();
ysr@777 2929 gclog_or_tty->print_cr(" compute known garbage: %8.3f ms.",
ysr@777 2930 (known_garbage_end - clear_marked_end)*1000.0);
ysr@777 2931 }
ysr@777 2932 _collectionSetChooser->sortMarkedHeapRegions();
ysr@777 2933 double sort_end;
ysr@777 2934 if (G1PrintParCleanupStats) {
ysr@777 2935 sort_end = os::elapsedTime();
ysr@777 2936 gclog_or_tty->print_cr(" sorting: %8.3f ms.",
ysr@777 2937 (sort_end - known_garbage_end)*1000.0);
ysr@777 2938 }
ysr@777 2939
ysr@777 2940 record_concurrent_mark_cleanup_end_work2();
ysr@777 2941 double work2_end;
ysr@777 2942 if (G1PrintParCleanupStats) {
ysr@777 2943 work2_end = os::elapsedTime();
ysr@777 2944 gclog_or_tty->print_cr(" work2: %8.3f ms.",
ysr@777 2945 (work2_end - sort_end)*1000.0);
ysr@777 2946 }
ysr@777 2947 }
ysr@777 2948
ysr@777 2949 // Add the heap region to the collection set and return the conservative
ysr@777 2950 // estimate of the number of live bytes.
ysr@777 2951 void G1CollectorPolicy::
ysr@777 2952 add_to_collection_set(HeapRegion* hr) {
tonyp@1717 2953 if (G1PrintHeapRegions) {
tonyp@1823 2954 gclog_or_tty->print_cr("added region to cset "
tonyp@1823 2955 "%d:["PTR_FORMAT", "PTR_FORMAT"], "
tonyp@1823 2956 "top "PTR_FORMAT", %s",
tonyp@1823 2957 hr->hrs_index(), hr->bottom(), hr->end(),
tonyp@1823 2958 hr->top(), hr->is_young() ? "YOUNG" : "NOT_YOUNG");
ysr@777 2959 }
ysr@777 2960
ysr@777 2961 if (_g1->mark_in_progress())
ysr@777 2962 _g1->concurrent_mark()->registerCSetRegion(hr);
ysr@777 2963
ysr@777 2964 assert(!hr->in_collection_set(),
ysr@777 2965 "should not already be in the CSet");
ysr@777 2966 hr->set_in_collection_set(true);
ysr@777 2967 hr->set_next_in_collection_set(_collection_set);
ysr@777 2968 _collection_set = hr;
ysr@777 2969 _collection_set_size++;
ysr@777 2970 _collection_set_bytes_used_before += hr->used();
tonyp@961 2971 _g1->register_region_with_in_cset_fast_test(hr);
ysr@777 2972 }
ysr@777 2973
ysr@777 2974 void
ysr@777 2975 G1CollectorPolicy_BestRegionsFirst::
apetrusenko@1112 2976 choose_collection_set() {
ysr@777 2977 double non_young_start_time_sec;
ysr@777 2978 start_recording_regions();
ysr@777 2979
ysr@1523 2980 guarantee(_target_pause_time_ms > -1.0
ysr@1523 2981 NOT_PRODUCT(|| Universe::heap()->gc_cause() == GCCause::_scavenge_alot),
apetrusenko@1112 2982 "_target_pause_time_ms should have been set!");
ysr@1523 2983 #ifndef PRODUCT
ysr@1523 2984 if (_target_pause_time_ms <= -1.0) {
ysr@1523 2985 assert(ScavengeALot && Universe::heap()->gc_cause() == GCCause::_scavenge_alot, "Error");
ysr@1523 2986 _target_pause_time_ms = _mmu_tracker->max_gc_time() * 1000.0;
ysr@1523 2987 }
ysr@1523 2988 #endif
apetrusenko@1112 2989 assert(_collection_set == NULL, "Precondition");
ysr@777 2990
ysr@777 2991 double base_time_ms = predict_base_elapsed_time_ms(_pending_cards);
ysr@777 2992 double predicted_pause_time_ms = base_time_ms;
ysr@777 2993
ysr@777 2994 double target_time_ms = _target_pause_time_ms;
ysr@777 2995 double time_remaining_ms = target_time_ms - base_time_ms;
ysr@777 2996
ysr@777 2997 // the 10% and 50% values are arbitrary...
ysr@777 2998 if (time_remaining_ms < 0.10*target_time_ms) {
ysr@777 2999 time_remaining_ms = 0.50 * target_time_ms;
ysr@777 3000 _within_target = false;
ysr@777 3001 } else {
ysr@777 3002 _within_target = true;
ysr@777 3003 }
ysr@777 3004
ysr@777 3005 // We figure out the number of bytes available for future to-space.
ysr@777 3006 // For new regions without marking information, we must assume the
ysr@777 3007 // worst-case of complete survival. If we have marking information for a
ysr@777 3008 // region, we can bound the amount of live data. We can add a number of
ysr@777 3009 // such regions, as long as the sum of the live data bounds does not
ysr@777 3010 // exceed the available evacuation space.
ysr@777 3011 size_t max_live_bytes = _g1->free_regions() * HeapRegion::GrainBytes;
ysr@777 3012
ysr@777 3013 size_t expansion_bytes =
ysr@777 3014 _g1->expansion_regions() * HeapRegion::GrainBytes;
ysr@777 3015
apetrusenko@1112 3016 _collection_set_bytes_used_before = 0;
apetrusenko@1112 3017 _collection_set_size = 0;
ysr@777 3018
ysr@777 3019 // Adjust for expansion and slop.
ysr@777 3020 max_live_bytes = max_live_bytes + expansion_bytes;
ysr@777 3021
apetrusenko@1112 3022 assert(_g1->regions_accounted_for(), "Region leakage!");
ysr@777 3023
ysr@777 3024 HeapRegion* hr;
ysr@777 3025 if (in_young_gc_mode()) {
ysr@777 3026 double young_start_time_sec = os::elapsedTime();
ysr@777 3027
ysr@777 3028 if (G1PolicyVerbose > 0) {
ysr@777 3029 gclog_or_tty->print_cr("Adding %d young regions to the CSet",
ysr@777 3030 _g1->young_list_length());
ysr@777 3031 }
ysr@777 3032 _young_cset_length = 0;
ysr@777 3033 _last_young_gc_full = full_young_gcs() ? true : false;
ysr@777 3034 if (_last_young_gc_full)
ysr@777 3035 ++_full_young_pause_num;
ysr@777 3036 else
ysr@777 3037 ++_partial_young_pause_num;
ysr@777 3038 hr = _g1->pop_region_from_young_list();
ysr@777 3039 while (hr != NULL) {
ysr@777 3040
ysr@777 3041 assert( hr->young_index_in_cset() == -1, "invariant" );
ysr@777 3042 assert( hr->age_in_surv_rate_group() != -1, "invariant" );
ysr@777 3043 hr->set_young_index_in_cset((int) _young_cset_length);
ysr@777 3044
ysr@777 3045 ++_young_cset_length;
ysr@777 3046 double predicted_time_ms = predict_region_elapsed_time_ms(hr, true);
ysr@777 3047 time_remaining_ms -= predicted_time_ms;
ysr@777 3048 predicted_pause_time_ms += predicted_time_ms;
apetrusenko@1112 3049 assert(!hr->in_collection_set(), "invariant");
apetrusenko@1112 3050 add_to_collection_set(hr);
apetrusenko@1112 3051 record_cset_region(hr, true);
ysr@777 3052 max_live_bytes -= MIN2(hr->max_live_bytes(), max_live_bytes);
ysr@777 3053 if (G1PolicyVerbose > 0) {
ysr@777 3054 gclog_or_tty->print_cr(" Added [" PTR_FORMAT ", " PTR_FORMAT") to CS.",
ysr@777 3055 hr->bottom(), hr->end());
ysr@777 3056 gclog_or_tty->print_cr(" (" SIZE_FORMAT " KB left in heap.)",
ysr@777 3057 max_live_bytes/K);
ysr@777 3058 }
ysr@777 3059 hr = _g1->pop_region_from_young_list();
ysr@777 3060 }
ysr@777 3061
ysr@777 3062 record_scan_only_regions(_g1->young_list_scan_only_length());
ysr@777 3063
ysr@777 3064 double young_end_time_sec = os::elapsedTime();
ysr@777 3065 _recorded_young_cset_choice_time_ms =
ysr@777 3066 (young_end_time_sec - young_start_time_sec) * 1000.0;
ysr@777 3067
ysr@777 3068 non_young_start_time_sec = os::elapsedTime();
ysr@777 3069
ysr@777 3070 if (_young_cset_length > 0 && _last_young_gc_full) {
ysr@777 3071 // don't bother adding more regions...
ysr@777 3072 goto choose_collection_set_end;
ysr@777 3073 }
ysr@777 3074 }
ysr@777 3075
ysr@777 3076 if (!in_young_gc_mode() || !full_young_gcs()) {
ysr@777 3077 bool should_continue = true;
ysr@777 3078 NumberSeq seq;
ysr@777 3079 double avg_prediction = 100000000000000000.0; // something very large
ysr@777 3080 do {
ysr@777 3081 hr = _collectionSetChooser->getNextMarkedRegion(time_remaining_ms,
ysr@777 3082 avg_prediction);
apetrusenko@1112 3083 if (hr != NULL) {
ysr@777 3084 double predicted_time_ms = predict_region_elapsed_time_ms(hr, false);
ysr@777 3085 time_remaining_ms -= predicted_time_ms;
ysr@777 3086 predicted_pause_time_ms += predicted_time_ms;
ysr@777 3087 add_to_collection_set(hr);
ysr@777 3088 record_cset_region(hr, false);
ysr@777 3089 max_live_bytes -= MIN2(hr->max_live_bytes(), max_live_bytes);
ysr@777 3090 if (G1PolicyVerbose > 0) {
ysr@777 3091 gclog_or_tty->print_cr(" (" SIZE_FORMAT " KB left in heap.)",
ysr@777 3092 max_live_bytes/K);
ysr@777 3093 }
ysr@777 3094 seq.add(predicted_time_ms);
ysr@777 3095 avg_prediction = seq.avg() + seq.sd();
ysr@777 3096 }
ysr@777 3097 should_continue =
ysr@777 3098 ( hr != NULL) &&
ysr@777 3099 ( (adaptive_young_list_length()) ? time_remaining_ms > 0.0
ysr@777 3100 : _collection_set_size < _young_list_fixed_length );
ysr@777 3101 } while (should_continue);
ysr@777 3102
ysr@777 3103 if (!adaptive_young_list_length() &&
ysr@777 3104 _collection_set_size < _young_list_fixed_length)
ysr@777 3105 _should_revert_to_full_young_gcs = true;
ysr@777 3106 }
ysr@777 3107
ysr@777 3108 choose_collection_set_end:
ysr@777 3109 count_CS_bytes_used();
ysr@777 3110
ysr@777 3111 end_recording_regions();
ysr@777 3112
ysr@777 3113 double non_young_end_time_sec = os::elapsedTime();
ysr@777 3114 _recorded_non_young_cset_choice_time_ms =
ysr@777 3115 (non_young_end_time_sec - non_young_start_time_sec) * 1000.0;
ysr@777 3116 }
ysr@777 3117
ysr@777 3118 void G1CollectorPolicy_BestRegionsFirst::record_full_collection_end() {
ysr@777 3119 G1CollectorPolicy::record_full_collection_end();
ysr@777 3120 _collectionSetChooser->updateAfterFullCollection();
ysr@777 3121 }
ysr@777 3122
ysr@777 3123 void G1CollectorPolicy_BestRegionsFirst::
ysr@777 3124 expand_if_possible(size_t numRegions) {
ysr@777 3125 size_t expansion_bytes = numRegions * HeapRegion::GrainBytes;
ysr@777 3126 _g1->expand(expansion_bytes);
ysr@777 3127 }
ysr@777 3128
ysr@777 3129 void G1CollectorPolicy_BestRegionsFirst::
apetrusenko@1112 3130 record_collection_pause_end(bool abandoned) {
apetrusenko@1112 3131 G1CollectorPolicy::record_collection_pause_end(abandoned);
ysr@777 3132 assert(assertMarkedBytesDataOK(), "Marked regions not OK at pause end.");
ysr@777 3133 }

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