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

Wed, 26 Oct 2011 08:44:53 +0200

author
brutisso
date
Wed, 26 Oct 2011 08:44:53 +0200
changeset 3221
dbfcbecbb2dc
parent 3219
c6a6e936dc68
child 3268
8aae2050e83e
permissions
-rw-r--r--

7102191: G1: assert(_min_desired_young_length <= initial_region_num) failed: Initial young gen size too small
Summary: initial_region_num actually not needed.
Reviewed-by: tonyp, johnc

ysr@777 1 /*
tonyp@2472 2 * Copyright (c) 2001, 2011, Oracle and/or its affiliates. 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 *
trims@1907 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907 20 * or visit www.oracle.com if you need additional information or have any
trims@1907 21 * questions.
ysr@777 22 *
ysr@777 23 */
ysr@777 24
stefank@2314 25 #include "precompiled.hpp"
stefank@2314 26 #include "gc_implementation/g1/concurrentG1Refine.hpp"
stefank@2314 27 #include "gc_implementation/g1/concurrentMark.hpp"
stefank@2314 28 #include "gc_implementation/g1/concurrentMarkThread.inline.hpp"
stefank@2314 29 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
stefank@2314 30 #include "gc_implementation/g1/g1CollectorPolicy.hpp"
tonyp@3114 31 #include "gc_implementation/g1/g1ErgoVerbose.hpp"
stefank@2314 32 #include "gc_implementation/g1/heapRegionRemSet.hpp"
stefank@2314 33 #include "gc_implementation/shared/gcPolicyCounters.hpp"
stefank@2314 34 #include "runtime/arguments.hpp"
stefank@2314 35 #include "runtime/java.hpp"
stefank@2314 36 #include "runtime/mutexLocker.hpp"
stefank@2314 37 #include "utilities/debug.hpp"
ysr@777 38
ysr@777 39 #define PREDICTIONS_VERBOSE 0
ysr@777 40
ysr@777 41 // <NEW PREDICTION>
ysr@777 42
ysr@777 43 // Different defaults for different number of GC threads
ysr@777 44 // They were chosen by running GCOld and SPECjbb on debris with different
ysr@777 45 // numbers of GC threads and choosing them based on the results
ysr@777 46
ysr@777 47 // all the same
ysr@777 48 static double rs_length_diff_defaults[] = {
ysr@777 49 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0
ysr@777 50 };
ysr@777 51
ysr@777 52 static double cost_per_card_ms_defaults[] = {
ysr@777 53 0.01, 0.005, 0.005, 0.003, 0.003, 0.002, 0.002, 0.0015
ysr@777 54 };
ysr@777 55
ysr@777 56 // all the same
ysr@777 57 static double fully_young_cards_per_entry_ratio_defaults[] = {
ysr@777 58 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0
ysr@777 59 };
ysr@777 60
ysr@777 61 static double cost_per_entry_ms_defaults[] = {
ysr@777 62 0.015, 0.01, 0.01, 0.008, 0.008, 0.0055, 0.0055, 0.005
ysr@777 63 };
ysr@777 64
ysr@777 65 static double cost_per_byte_ms_defaults[] = {
ysr@777 66 0.00006, 0.00003, 0.00003, 0.000015, 0.000015, 0.00001, 0.00001, 0.000009
ysr@777 67 };
ysr@777 68
ysr@777 69 // these should be pretty consistent
ysr@777 70 static double constant_other_time_ms_defaults[] = {
ysr@777 71 5.0, 5.0, 5.0, 5.0, 5.0, 5.0, 5.0, 5.0
ysr@777 72 };
ysr@777 73
ysr@777 74
ysr@777 75 static double young_other_cost_per_region_ms_defaults[] = {
ysr@777 76 0.3, 0.2, 0.2, 0.15, 0.15, 0.12, 0.12, 0.1
ysr@777 77 };
ysr@777 78
ysr@777 79 static double non_young_other_cost_per_region_ms_defaults[] = {
ysr@777 80 1.0, 0.7, 0.7, 0.5, 0.5, 0.42, 0.42, 0.30
ysr@777 81 };
ysr@777 82
ysr@777 83 // </NEW PREDICTION>
ysr@777 84
brutisso@2645 85 // Help class for avoiding interleaved logging
brutisso@2645 86 class LineBuffer: public StackObj {
brutisso@2645 87
brutisso@2645 88 private:
brutisso@2645 89 static const int BUFFER_LEN = 1024;
brutisso@2645 90 static const int INDENT_CHARS = 3;
brutisso@2645 91 char _buffer[BUFFER_LEN];
brutisso@2645 92 int _indent_level;
brutisso@2645 93 int _cur;
brutisso@2645 94
brutisso@2645 95 void vappend(const char* format, va_list ap) {
brutisso@2645 96 int res = vsnprintf(&_buffer[_cur], BUFFER_LEN - _cur, format, ap);
brutisso@2645 97 if (res != -1) {
brutisso@2645 98 _cur += res;
brutisso@2645 99 } else {
brutisso@2645 100 DEBUG_ONLY(warning("buffer too small in LineBuffer");)
brutisso@2645 101 _buffer[BUFFER_LEN -1] = 0;
brutisso@2645 102 _cur = BUFFER_LEN; // vsnprintf above should not add to _buffer if we are called again
brutisso@2645 103 }
brutisso@2645 104 }
brutisso@2645 105
brutisso@2645 106 public:
brutisso@2645 107 explicit LineBuffer(int indent_level): _indent_level(indent_level), _cur(0) {
brutisso@2645 108 for (; (_cur < BUFFER_LEN && _cur < (_indent_level * INDENT_CHARS)); _cur++) {
brutisso@2645 109 _buffer[_cur] = ' ';
brutisso@2645 110 }
brutisso@2645 111 }
brutisso@2645 112
brutisso@2645 113 #ifndef PRODUCT
brutisso@2645 114 ~LineBuffer() {
brutisso@2645 115 assert(_cur == _indent_level * INDENT_CHARS, "pending data in buffer - append_and_print_cr() not called?");
brutisso@2645 116 }
brutisso@2645 117 #endif
brutisso@2645 118
brutisso@2645 119 void append(const char* format, ...) {
brutisso@2645 120 va_list ap;
brutisso@2645 121 va_start(ap, format);
brutisso@2645 122 vappend(format, ap);
brutisso@2645 123 va_end(ap);
brutisso@2645 124 }
brutisso@2645 125
brutisso@2645 126 void append_and_print_cr(const char* format, ...) {
brutisso@2645 127 va_list ap;
brutisso@2645 128 va_start(ap, format);
brutisso@2645 129 vappend(format, ap);
brutisso@2645 130 va_end(ap);
brutisso@2645 131 gclog_or_tty->print_cr("%s", _buffer);
brutisso@2645 132 _cur = _indent_level * INDENT_CHARS;
brutisso@2645 133 }
brutisso@2645 134 };
brutisso@2645 135
ysr@777 136 G1CollectorPolicy::G1CollectorPolicy() :
jmasa@2188 137 _parallel_gc_threads(G1CollectedHeap::use_parallel_gc_threads()
johnc@3021 138 ? ParallelGCThreads : 1),
jmasa@2188 139
ysr@777 140 _n_pauses(0),
johnc@3021 141 _recent_rs_scan_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 142 _recent_pause_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 143 _recent_rs_sizes(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 144 _recent_gc_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 145 _all_pause_times_ms(new NumberSeq()),
ysr@777 146 _stop_world_start(0.0),
ysr@777 147 _all_stop_world_times_ms(new NumberSeq()),
ysr@777 148 _all_yield_times_ms(new NumberSeq()),
brutisso@3120 149 _using_new_ratio_calculations(false),
ysr@777 150
ysr@777 151 _all_mod_union_times_ms(new NumberSeq()),
ysr@777 152
apetrusenko@1112 153 _summary(new Summary()),
ysr@777 154
johnc@3175 155 _cur_clear_ct_time_ms(0.0),
johnc@3175 156
johnc@3175 157 _cur_ref_proc_time_ms(0.0),
johnc@3175 158 _cur_ref_enq_time_ms(0.0),
johnc@3175 159
johnc@1325 160 #ifndef PRODUCT
johnc@1325 161 _min_clear_cc_time_ms(-1.0),
johnc@1325 162 _max_clear_cc_time_ms(-1.0),
johnc@1325 163 _cur_clear_cc_time_ms(0.0),
johnc@1325 164 _cum_clear_cc_time_ms(0.0),
johnc@1325 165 _num_cc_clears(0L),
johnc@1325 166 #endif
ysr@777 167
ysr@777 168 _region_num_young(0),
ysr@777 169 _region_num_tenured(0),
ysr@777 170 _prev_region_num_young(0),
ysr@777 171 _prev_region_num_tenured(0),
ysr@777 172
ysr@777 173 _aux_num(10),
ysr@777 174 _all_aux_times_ms(new NumberSeq[_aux_num]),
ysr@777 175 _cur_aux_start_times_ms(new double[_aux_num]),
ysr@777 176 _cur_aux_times_ms(new double[_aux_num]),
ysr@777 177 _cur_aux_times_set(new bool[_aux_num]),
ysr@777 178
ysr@777 179 _concurrent_mark_remark_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 180 _concurrent_mark_cleanup_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 181
ysr@777 182 // <NEW PREDICTION>
ysr@777 183
ysr@777 184 _alloc_rate_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 185 _prev_collection_pause_end_ms(0.0),
ysr@777 186 _pending_card_diff_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 187 _rs_length_diff_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 188 _cost_per_card_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 189 _fully_young_cards_per_entry_ratio_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 190 _partially_young_cards_per_entry_ratio_seq(
ysr@777 191 new TruncatedSeq(TruncatedSeqLength)),
ysr@777 192 _cost_per_entry_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 193 _partially_young_cost_per_entry_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 194 _cost_per_byte_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 195 _cost_per_byte_ms_during_cm_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 196 _constant_other_time_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 197 _young_other_cost_per_region_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 198 _non_young_other_cost_per_region_ms_seq(
ysr@777 199 new TruncatedSeq(TruncatedSeqLength)),
ysr@777 200
ysr@777 201 _pending_cards_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 202 _scanned_cards_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 203 _rs_lengths_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 204
johnc@1186 205 _pause_time_target_ms((double) MaxGCPauseMillis),
ysr@777 206
ysr@777 207 // </NEW PREDICTION>
ysr@777 208
ysr@777 209 _full_young_gcs(true),
ysr@777 210 _full_young_pause_num(0),
ysr@777 211 _partial_young_pause_num(0),
ysr@777 212
ysr@777 213 _during_marking(false),
ysr@777 214 _in_marking_window(false),
ysr@777 215 _in_marking_window_im(false),
ysr@777 216
ysr@777 217 _known_garbage_ratio(0.0),
ysr@777 218 _known_garbage_bytes(0),
ysr@777 219
ysr@777 220 _young_gc_eff_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 221
ysr@777 222 _recent_prev_end_times_for_all_gcs_sec(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 223
ysr@777 224 _recent_CS_bytes_used_before(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 225 _recent_CS_bytes_surviving(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 226
ysr@777 227 _recent_avg_pause_time_ratio(0.0),
ysr@777 228
ysr@777 229 _all_full_gc_times_ms(new NumberSeq()),
ysr@777 230
ysr@777 231 // G1PausesBtwnConcMark defaults to -1
ysr@777 232 // so the hack is to do the cast QQQ FIXME
ysr@777 233 _pauses_btwn_concurrent_mark((size_t)G1PausesBtwnConcMark),
tonyp@1794 234 _initiate_conc_mark_if_possible(false),
tonyp@1794 235 _during_initial_mark_pause(false),
ysr@777 236 _should_revert_to_full_young_gcs(false),
ysr@777 237 _last_full_young_gc(false),
ysr@777 238
tonyp@2961 239 _eden_bytes_before_gc(0),
tonyp@2961 240 _survivor_bytes_before_gc(0),
tonyp@2961 241 _capacity_before_gc(0),
tonyp@2961 242
ysr@777 243 _prev_collection_pause_used_at_end_bytes(0),
ysr@777 244
ysr@777 245 _collection_set(NULL),
johnc@1829 246 _collection_set_size(0),
johnc@1829 247 _collection_set_bytes_used_before(0),
johnc@1829 248
johnc@1829 249 // Incremental CSet attributes
johnc@1829 250 _inc_cset_build_state(Inactive),
johnc@1829 251 _inc_cset_head(NULL),
johnc@1829 252 _inc_cset_tail(NULL),
johnc@1829 253 _inc_cset_size(0),
johnc@1829 254 _inc_cset_young_index(0),
johnc@1829 255 _inc_cset_bytes_used_before(0),
johnc@1829 256 _inc_cset_max_finger(NULL),
johnc@1829 257 _inc_cset_recorded_young_bytes(0),
johnc@1829 258 _inc_cset_recorded_rs_lengths(0),
johnc@1829 259 _inc_cset_predicted_elapsed_time_ms(0.0),
johnc@1829 260 _inc_cset_predicted_bytes_to_copy(0),
johnc@1829 261
ysr@777 262 #ifdef _MSC_VER // the use of 'this' below gets a warning, make it go away
ysr@777 263 #pragma warning( disable:4355 ) // 'this' : used in base member initializer list
ysr@777 264 #endif // _MSC_VER
ysr@777 265
ysr@777 266 _short_lived_surv_rate_group(new SurvRateGroup(this, "Short Lived",
ysr@777 267 G1YoungSurvRateNumRegionsSummary)),
ysr@777 268 _survivor_surv_rate_group(new SurvRateGroup(this, "Survivor",
apetrusenko@980 269 G1YoungSurvRateNumRegionsSummary)),
ysr@777 270 // add here any more surv rate groups
apetrusenko@980 271 _recorded_survivor_regions(0),
apetrusenko@980 272 _recorded_survivor_head(NULL),
apetrusenko@980 273 _recorded_survivor_tail(NULL),
tonyp@1791 274 _survivors_age_table(true),
tonyp@1791 275
tonyp@3114 276 _gc_overhead_perc(0.0) {
tonyp@3114 277
tonyp@1377 278 // Set up the region size and associated fields. Given that the
tonyp@1377 279 // policy is created before the heap, we have to set this up here,
tonyp@1377 280 // so it's done as soon as possible.
tonyp@1377 281 HeapRegion::setup_heap_region_size(Arguments::min_heap_size());
iveresov@1696 282 HeapRegionRemSet::setup_remset_size();
tonyp@1377 283
tonyp@3114 284 G1ErgoVerbose::initialize();
tonyp@3114 285 if (PrintAdaptiveSizePolicy) {
tonyp@3114 286 // Currently, we only use a single switch for all the heuristics.
tonyp@3114 287 G1ErgoVerbose::set_enabled(true);
tonyp@3114 288 // Given that we don't currently have a verboseness level
tonyp@3114 289 // parameter, we'll hardcode this to high. This can be easily
tonyp@3114 290 // changed in the future.
tonyp@3114 291 G1ErgoVerbose::set_level(ErgoHigh);
tonyp@3114 292 } else {
tonyp@3114 293 G1ErgoVerbose::set_enabled(false);
tonyp@3114 294 }
tonyp@3114 295
apetrusenko@1826 296 // Verify PLAB sizes
johnc@3182 297 const size_t region_size = HeapRegion::GrainWords;
apetrusenko@1826 298 if (YoungPLABSize > region_size || OldPLABSize > region_size) {
apetrusenko@1826 299 char buffer[128];
johnc@3182 300 jio_snprintf(buffer, sizeof(buffer), "%sPLABSize should be at most "SIZE_FORMAT,
apetrusenko@1826 301 OldPLABSize > region_size ? "Old" : "Young", region_size);
apetrusenko@1826 302 vm_exit_during_initialization(buffer);
apetrusenko@1826 303 }
apetrusenko@1826 304
ysr@777 305 _recent_prev_end_times_for_all_gcs_sec->add(os::elapsedTime());
ysr@777 306 _prev_collection_pause_end_ms = os::elapsedTime() * 1000.0;
ysr@777 307
tonyp@1966 308 _par_last_gc_worker_start_times_ms = new double[_parallel_gc_threads];
ysr@777 309 _par_last_ext_root_scan_times_ms = new double[_parallel_gc_threads];
ysr@777 310 _par_last_mark_stack_scan_times_ms = new double[_parallel_gc_threads];
ysr@777 311
ysr@777 312 _par_last_update_rs_times_ms = new double[_parallel_gc_threads];
ysr@777 313 _par_last_update_rs_processed_buffers = new double[_parallel_gc_threads];
ysr@777 314
ysr@777 315 _par_last_scan_rs_times_ms = new double[_parallel_gc_threads];
ysr@777 316
ysr@777 317 _par_last_obj_copy_times_ms = new double[_parallel_gc_threads];
ysr@777 318
ysr@777 319 _par_last_termination_times_ms = new double[_parallel_gc_threads];
tonyp@1966 320 _par_last_termination_attempts = new double[_parallel_gc_threads];
tonyp@1966 321 _par_last_gc_worker_end_times_ms = new double[_parallel_gc_threads];
brutisso@2712 322 _par_last_gc_worker_times_ms = new double[_parallel_gc_threads];
johnc@3219 323 _par_last_gc_worker_other_times_ms = new double[_parallel_gc_threads];
ysr@777 324
ysr@777 325 // start conservatively
johnc@1186 326 _expensive_region_limit_ms = 0.5 * (double) MaxGCPauseMillis;
ysr@777 327
ysr@777 328 // <NEW PREDICTION>
ysr@777 329
ysr@777 330 int index;
ysr@777 331 if (ParallelGCThreads == 0)
ysr@777 332 index = 0;
ysr@777 333 else if (ParallelGCThreads > 8)
ysr@777 334 index = 7;
ysr@777 335 else
ysr@777 336 index = ParallelGCThreads - 1;
ysr@777 337
ysr@777 338 _pending_card_diff_seq->add(0.0);
ysr@777 339 _rs_length_diff_seq->add(rs_length_diff_defaults[index]);
ysr@777 340 _cost_per_card_ms_seq->add(cost_per_card_ms_defaults[index]);
ysr@777 341 _fully_young_cards_per_entry_ratio_seq->add(
ysr@777 342 fully_young_cards_per_entry_ratio_defaults[index]);
ysr@777 343 _cost_per_entry_ms_seq->add(cost_per_entry_ms_defaults[index]);
ysr@777 344 _cost_per_byte_ms_seq->add(cost_per_byte_ms_defaults[index]);
ysr@777 345 _constant_other_time_ms_seq->add(constant_other_time_ms_defaults[index]);
ysr@777 346 _young_other_cost_per_region_ms_seq->add(
ysr@777 347 young_other_cost_per_region_ms_defaults[index]);
ysr@777 348 _non_young_other_cost_per_region_ms_seq->add(
ysr@777 349 non_young_other_cost_per_region_ms_defaults[index]);
ysr@777 350
ysr@777 351 // </NEW PREDICTION>
ysr@777 352
tonyp@1965 353 // Below, we might need to calculate the pause time target based on
tonyp@1965 354 // the pause interval. When we do so we are going to give G1 maximum
tonyp@1965 355 // flexibility and allow it to do pauses when it needs to. So, we'll
tonyp@1965 356 // arrange that the pause interval to be pause time target + 1 to
tonyp@1965 357 // ensure that a) the pause time target is maximized with respect to
tonyp@1965 358 // the pause interval and b) we maintain the invariant that pause
tonyp@1965 359 // time target < pause interval. If the user does not want this
tonyp@1965 360 // maximum flexibility, they will have to set the pause interval
tonyp@1965 361 // explicitly.
tonyp@1965 362
tonyp@1965 363 // First make sure that, if either parameter is set, its value is
tonyp@1965 364 // reasonable.
tonyp@1965 365 if (!FLAG_IS_DEFAULT(MaxGCPauseMillis)) {
tonyp@1965 366 if (MaxGCPauseMillis < 1) {
tonyp@1965 367 vm_exit_during_initialization("MaxGCPauseMillis should be "
tonyp@1965 368 "greater than 0");
tonyp@1965 369 }
tonyp@1965 370 }
tonyp@1965 371 if (!FLAG_IS_DEFAULT(GCPauseIntervalMillis)) {
tonyp@1965 372 if (GCPauseIntervalMillis < 1) {
tonyp@1965 373 vm_exit_during_initialization("GCPauseIntervalMillis should be "
tonyp@1965 374 "greater than 0");
tonyp@1965 375 }
tonyp@1965 376 }
tonyp@1965 377
tonyp@1965 378 // Then, if the pause time target parameter was not set, set it to
tonyp@1965 379 // the default value.
tonyp@1965 380 if (FLAG_IS_DEFAULT(MaxGCPauseMillis)) {
tonyp@1965 381 if (FLAG_IS_DEFAULT(GCPauseIntervalMillis)) {
tonyp@1965 382 // The default pause time target in G1 is 200ms
tonyp@1965 383 FLAG_SET_DEFAULT(MaxGCPauseMillis, 200);
tonyp@1965 384 } else {
tonyp@1965 385 // We do not allow the pause interval to be set without the
tonyp@1965 386 // pause time target
tonyp@1965 387 vm_exit_during_initialization("GCPauseIntervalMillis cannot be set "
tonyp@1965 388 "without setting MaxGCPauseMillis");
tonyp@1965 389 }
tonyp@1965 390 }
tonyp@1965 391
tonyp@1965 392 // Then, if the interval parameter was not set, set it according to
tonyp@1965 393 // the pause time target (this will also deal with the case when the
tonyp@1965 394 // pause time target is the default value).
tonyp@1965 395 if (FLAG_IS_DEFAULT(GCPauseIntervalMillis)) {
tonyp@1965 396 FLAG_SET_DEFAULT(GCPauseIntervalMillis, MaxGCPauseMillis + 1);
tonyp@1965 397 }
tonyp@1965 398
tonyp@1965 399 // Finally, make sure that the two parameters are consistent.
tonyp@1965 400 if (MaxGCPauseMillis >= GCPauseIntervalMillis) {
tonyp@1965 401 char buffer[256];
tonyp@1965 402 jio_snprintf(buffer, 256,
tonyp@1965 403 "MaxGCPauseMillis (%u) should be less than "
tonyp@1965 404 "GCPauseIntervalMillis (%u)",
tonyp@1965 405 MaxGCPauseMillis, GCPauseIntervalMillis);
tonyp@1965 406 vm_exit_during_initialization(buffer);
tonyp@1965 407 }
tonyp@1965 408
tonyp@1965 409 double max_gc_time = (double) MaxGCPauseMillis / 1000.0;
johnc@1186 410 double time_slice = (double) GCPauseIntervalMillis / 1000.0;
ysr@777 411 _mmu_tracker = new G1MMUTrackerQueue(time_slice, max_gc_time);
johnc@1186 412 _sigma = (double) G1ConfidencePercent / 100.0;
ysr@777 413
ysr@777 414 // start conservatively (around 50ms is about right)
ysr@777 415 _concurrent_mark_remark_times_ms->add(0.05);
ysr@777 416 _concurrent_mark_cleanup_times_ms->add(0.20);
ysr@777 417 _tenuring_threshold = MaxTenuringThreshold;
tonyp@3066 418 // _max_survivor_regions will be calculated by
tonyp@3119 419 // update_young_list_target_length() during initialization.
tonyp@3066 420 _max_survivor_regions = 0;
apetrusenko@980 421
tonyp@1791 422 assert(GCTimeRatio > 0,
tonyp@1791 423 "we should have set it to a default value set_g1_gc_flags() "
tonyp@1791 424 "if a user set it to 0");
tonyp@1791 425 _gc_overhead_perc = 100.0 * (1.0 / (1.0 + GCTimeRatio));
tonyp@1791 426
tonyp@3119 427 uintx reserve_perc = G1ReservePercent;
tonyp@3119 428 // Put an artificial ceiling on this so that it's not set to a silly value.
tonyp@3119 429 if (reserve_perc > 50) {
tonyp@3119 430 reserve_perc = 50;
tonyp@3119 431 warning("G1ReservePercent is set to a value that is too large, "
tonyp@3119 432 "it's been updated to %u", reserve_perc);
tonyp@3119 433 }
tonyp@3119 434 _reserve_factor = (double) reserve_perc / 100.0;
brutisso@3120 435 // This will be set when the heap is expanded
tonyp@3119 436 // for the first time during initialization.
tonyp@3119 437 _reserve_regions = 0;
tonyp@3119 438
ysr@777 439 initialize_all();
tonyp@3209 440 _collectionSetChooser = new CollectionSetChooser();
ysr@777 441 }
ysr@777 442
ysr@777 443 // Increment "i", mod "len"
ysr@777 444 static void inc_mod(int& i, int len) {
ysr@777 445 i++; if (i == len) i = 0;
ysr@777 446 }
ysr@777 447
ysr@777 448 void G1CollectorPolicy::initialize_flags() {
ysr@777 449 set_min_alignment(HeapRegion::GrainBytes);
ysr@777 450 set_max_alignment(GenRemSet::max_alignment_constraint(rem_set_name()));
apetrusenko@982 451 if (SurvivorRatio < 1) {
apetrusenko@982 452 vm_exit_during_initialization("Invalid survivor ratio specified");
apetrusenko@982 453 }
ysr@777 454 CollectorPolicy::initialize_flags();
ysr@777 455 }
ysr@777 456
tonyp@1720 457 // The easiest way to deal with the parsing of the NewSize /
tonyp@1720 458 // MaxNewSize / etc. parameteres is to re-use the code in the
tonyp@1720 459 // TwoGenerationCollectorPolicy class. This is similar to what
tonyp@1720 460 // ParallelScavenge does with its GenerationSizer class (see
tonyp@1720 461 // ParallelScavengeHeap::initialize()). We might change this in the
tonyp@1720 462 // future, but it's a good start.
tonyp@1720 463 class G1YoungGenSizer : public TwoGenerationCollectorPolicy {
tonyp@3172 464 private:
tonyp@3172 465 size_t size_to_region_num(size_t byte_size) {
tonyp@3172 466 return MAX2((size_t) 1, byte_size / HeapRegion::GrainBytes);
tonyp@3172 467 }
tonyp@1720 468
tonyp@1720 469 public:
tonyp@1720 470 G1YoungGenSizer() {
tonyp@1720 471 initialize_flags();
tonyp@1720 472 initialize_size_info();
tonyp@1720 473 }
tonyp@1720 474 size_t min_young_region_num() {
tonyp@1720 475 return size_to_region_num(_min_gen0_size);
tonyp@1720 476 }
tonyp@1720 477 size_t initial_young_region_num() {
tonyp@1720 478 return size_to_region_num(_initial_gen0_size);
tonyp@1720 479 }
tonyp@1720 480 size_t max_young_region_num() {
tonyp@1720 481 return size_to_region_num(_max_gen0_size);
tonyp@1720 482 }
tonyp@1720 483 };
tonyp@1720 484
brutisso@3120 485 void G1CollectorPolicy::update_young_list_size_using_newratio(size_t number_of_heap_regions) {
brutisso@3120 486 assert(number_of_heap_regions > 0, "Heap must be initialized");
brutisso@3120 487 size_t young_size = number_of_heap_regions / (NewRatio + 1);
brutisso@3120 488 _min_desired_young_length = young_size;
brutisso@3120 489 _max_desired_young_length = young_size;
brutisso@3120 490 }
brutisso@3120 491
ysr@777 492 void G1CollectorPolicy::init() {
ysr@777 493 // Set aside an initial future to_space.
ysr@777 494 _g1 = G1CollectedHeap::heap();
ysr@777 495
ysr@777 496 assert(Heap_lock->owned_by_self(), "Locking discipline.");
ysr@777 497
apetrusenko@980 498 initialize_gc_policy_counters();
apetrusenko@980 499
brutisso@3065 500 G1YoungGenSizer sizer;
brutisso@3120 501 _min_desired_young_length = sizer.min_young_region_num();
brutisso@3120 502 _max_desired_young_length = sizer.max_young_region_num();
brutisso@3120 503
brutisso@3120 504 if (FLAG_IS_CMDLINE(NewRatio)) {
brutisso@3120 505 if (FLAG_IS_CMDLINE(NewSize) || FLAG_IS_CMDLINE(MaxNewSize)) {
tonyp@3172 506 warning("-XX:NewSize and -XX:MaxNewSize override -XX:NewRatio");
brutisso@3120 507 } else {
brutisso@3120 508 // Treat NewRatio as a fixed size that is only recalculated when the heap size changes
tonyp@3172 509 update_young_list_size_using_newratio(_g1->n_regions());
brutisso@3120 510 _using_new_ratio_calculations = true;
brutisso@3120 511 }
brutisso@3120 512 }
brutisso@3120 513
brutisso@3120 514 assert(_min_desired_young_length <= _max_desired_young_length, "Invalid min/max young gen size values");
brutisso@3120 515
brutisso@3120 516 set_adaptive_young_list_length(_min_desired_young_length < _max_desired_young_length);
brutisso@3120 517 if (adaptive_young_list_length()) {
brutisso@3065 518 _young_list_fixed_length = 0;
johnc@1829 519 } else {
brutisso@3221 520 assert(_min_desired_young_length == _max_desired_young_length, "Min and max young size differ");
brutisso@3221 521 _young_list_fixed_length = _min_desired_young_length;
ysr@777 522 }
brutisso@3065 523 _free_regions_at_end_of_collection = _g1->free_regions();
tonyp@3119 524 update_young_list_target_length();
brutisso@3120 525 _prev_eden_capacity = _young_list_target_length * HeapRegion::GrainBytes;
johnc@1829 526
johnc@1829 527 // We may immediately start allocating regions and placing them on the
johnc@1829 528 // collection set list. Initialize the per-collection set info
johnc@1829 529 start_incremental_cset_building();
ysr@777 530 }
ysr@777 531
apetrusenko@980 532 // Create the jstat counters for the policy.
tonyp@3119 533 void G1CollectorPolicy::initialize_gc_policy_counters() {
brutisso@3065 534 _gc_policy_counters = new GCPolicyCounters("GarbageFirst", 1, 3);
apetrusenko@980 535 }
apetrusenko@980 536
tonyp@3119 537 bool G1CollectorPolicy::predict_will_fit(size_t young_length,
tonyp@3119 538 double base_time_ms,
tonyp@3119 539 size_t base_free_regions,
tonyp@3119 540 double target_pause_time_ms) {
tonyp@3119 541 if (young_length >= base_free_regions) {
tonyp@3119 542 // end condition 1: not enough space for the young regions
tonyp@3119 543 return false;
ysr@777 544 }
tonyp@3119 545
tonyp@3119 546 double accum_surv_rate = accum_yg_surv_rate_pred((int)(young_length - 1));
tonyp@3119 547 size_t bytes_to_copy =
tonyp@3119 548 (size_t) (accum_surv_rate * (double) HeapRegion::GrainBytes);
tonyp@3119 549 double copy_time_ms = predict_object_copy_time_ms(bytes_to_copy);
tonyp@3119 550 double young_other_time_ms = predict_young_other_time_ms(young_length);
tonyp@3119 551 double pause_time_ms = base_time_ms + copy_time_ms + young_other_time_ms;
tonyp@3119 552 if (pause_time_ms > target_pause_time_ms) {
tonyp@3119 553 // end condition 2: prediction is over the target pause time
tonyp@3119 554 return false;
tonyp@3119 555 }
tonyp@3119 556
tonyp@3119 557 size_t free_bytes =
tonyp@3119 558 (base_free_regions - young_length) * HeapRegion::GrainBytes;
tonyp@3119 559 if ((2.0 * sigma()) * (double) bytes_to_copy > (double) free_bytes) {
tonyp@3119 560 // end condition 3: out-of-space (conservatively!)
tonyp@3119 561 return false;
tonyp@3119 562 }
tonyp@3119 563
tonyp@3119 564 // success!
tonyp@3119 565 return true;
ysr@777 566 }
ysr@777 567
brutisso@3120 568 void G1CollectorPolicy::record_new_heap_size(size_t new_number_of_regions) {
brutisso@3120 569 // re-calculate the necessary reserve
brutisso@3120 570 double reserve_regions_d = (double) new_number_of_regions * _reserve_factor;
tonyp@3119 571 // We use ceiling so that if reserve_regions_d is > 0.0 (but
tonyp@3119 572 // smaller than 1.0) we'll get 1.
tonyp@3119 573 _reserve_regions = (size_t) ceil(reserve_regions_d);
brutisso@3120 574
brutisso@3120 575 if (_using_new_ratio_calculations) {
brutisso@3120 576 // -XX:NewRatio was specified so we need to update the
brutisso@3120 577 // young gen length when the heap size has changed.
brutisso@3120 578 update_young_list_size_using_newratio(new_number_of_regions);
brutisso@3120 579 }
tonyp@3119 580 }
tonyp@3119 581
tonyp@3119 582 size_t G1CollectorPolicy::calculate_young_list_desired_min_length(
tonyp@3119 583 size_t base_min_length) {
tonyp@3119 584 size_t desired_min_length = 0;
ysr@777 585 if (adaptive_young_list_length()) {
tonyp@3119 586 if (_alloc_rate_ms_seq->num() > 3) {
tonyp@3119 587 double now_sec = os::elapsedTime();
tonyp@3119 588 double when_ms = _mmu_tracker->when_max_gc_sec(now_sec) * 1000.0;
tonyp@3119 589 double alloc_rate_ms = predict_alloc_rate_ms();
tonyp@3119 590 desired_min_length = (size_t) ceil(alloc_rate_ms * when_ms);
tonyp@3119 591 } else {
tonyp@3119 592 // otherwise we don't have enough info to make the prediction
tonyp@3119 593 }
ysr@777 594 }
brutisso@3120 595 desired_min_length += base_min_length;
brutisso@3120 596 // make sure we don't go below any user-defined minimum bound
brutisso@3120 597 return MAX2(_min_desired_young_length, desired_min_length);
ysr@777 598 }
ysr@777 599
tonyp@3119 600 size_t G1CollectorPolicy::calculate_young_list_desired_max_length() {
tonyp@3119 601 // Here, we might want to also take into account any additional
tonyp@3119 602 // constraints (i.e., user-defined minimum bound). Currently, we
tonyp@3119 603 // effectively don't set this bound.
brutisso@3120 604 return _max_desired_young_length;
tonyp@3119 605 }
tonyp@3119 606
tonyp@3119 607 void G1CollectorPolicy::update_young_list_target_length(size_t rs_lengths) {
tonyp@3119 608 if (rs_lengths == (size_t) -1) {
tonyp@3119 609 // if it's set to the default value (-1), we should predict it;
tonyp@3119 610 // otherwise, use the given value.
tonyp@3119 611 rs_lengths = (size_t) get_new_prediction(_rs_lengths_seq);
tonyp@3119 612 }
tonyp@3119 613
tonyp@3119 614 // Calculate the absolute and desired min bounds.
tonyp@3119 615
tonyp@3119 616 // This is how many young regions we already have (currently: the survivors).
tonyp@3119 617 size_t base_min_length = recorded_survivor_regions();
tonyp@3119 618 // This is the absolute minimum young length, which ensures that we
tonyp@3119 619 // can allocate one eden region in the worst-case.
tonyp@3119 620 size_t absolute_min_length = base_min_length + 1;
tonyp@3119 621 size_t desired_min_length =
tonyp@3119 622 calculate_young_list_desired_min_length(base_min_length);
tonyp@3119 623 if (desired_min_length < absolute_min_length) {
tonyp@3119 624 desired_min_length = absolute_min_length;
tonyp@3119 625 }
tonyp@3119 626
tonyp@3119 627 // Calculate the absolute and desired max bounds.
tonyp@3119 628
tonyp@3119 629 // We will try our best not to "eat" into the reserve.
tonyp@3119 630 size_t absolute_max_length = 0;
tonyp@3119 631 if (_free_regions_at_end_of_collection > _reserve_regions) {
tonyp@3119 632 absolute_max_length = _free_regions_at_end_of_collection - _reserve_regions;
tonyp@3119 633 }
tonyp@3119 634 size_t desired_max_length = calculate_young_list_desired_max_length();
tonyp@3119 635 if (desired_max_length > absolute_max_length) {
tonyp@3119 636 desired_max_length = absolute_max_length;
tonyp@3119 637 }
tonyp@3119 638
tonyp@3119 639 size_t young_list_target_length = 0;
tonyp@3119 640 if (adaptive_young_list_length()) {
tonyp@3119 641 if (full_young_gcs()) {
tonyp@3119 642 young_list_target_length =
tonyp@3119 643 calculate_young_list_target_length(rs_lengths,
tonyp@3119 644 base_min_length,
tonyp@3119 645 desired_min_length,
tonyp@3119 646 desired_max_length);
tonyp@3119 647 _rs_lengths_prediction = rs_lengths;
tonyp@3119 648 } else {
tonyp@3119 649 // Don't calculate anything and let the code below bound it to
tonyp@3119 650 // the desired_min_length, i.e., do the next GC as soon as
tonyp@3119 651 // possible to maximize how many old regions we can add to it.
ysr@777 652 }
ysr@777 653 } else {
tonyp@3119 654 if (full_young_gcs()) {
tonyp@3119 655 young_list_target_length = _young_list_fixed_length;
tonyp@3119 656 } else {
tonyp@3119 657 // A bit arbitrary: during partially-young GCs we allocate half
tonyp@3119 658 // the young regions to try to add old regions to the CSet.
tonyp@3119 659 young_list_target_length = _young_list_fixed_length / 2;
tonyp@3119 660 // We choose to accept that we might go under the desired min
tonyp@3119 661 // length given that we intentionally ask for a smaller young gen.
tonyp@3119 662 desired_min_length = absolute_min_length;
tonyp@3119 663 }
ysr@777 664 }
ysr@777 665
tonyp@3119 666 // Make sure we don't go over the desired max length, nor under the
tonyp@3119 667 // desired min length. In case they clash, desired_min_length wins
tonyp@3119 668 // which is why that test is second.
tonyp@3119 669 if (young_list_target_length > desired_max_length) {
tonyp@3119 670 young_list_target_length = desired_max_length;
tonyp@3119 671 }
tonyp@3119 672 if (young_list_target_length < desired_min_length) {
tonyp@3119 673 young_list_target_length = desired_min_length;
tonyp@3119 674 }
tonyp@3119 675
tonyp@3119 676 assert(young_list_target_length > recorded_survivor_regions(),
tonyp@3119 677 "we should be able to allocate at least one eden region");
tonyp@3119 678 assert(young_list_target_length >= absolute_min_length, "post-condition");
tonyp@3119 679 _young_list_target_length = young_list_target_length;
tonyp@3119 680
tonyp@3119 681 update_max_gc_locker_expansion();
ysr@777 682 }
ysr@777 683
tonyp@3119 684 size_t
tonyp@3119 685 G1CollectorPolicy::calculate_young_list_target_length(size_t rs_lengths,
tonyp@3119 686 size_t base_min_length,
tonyp@3119 687 size_t desired_min_length,
tonyp@3119 688 size_t desired_max_length) {
tonyp@3119 689 assert(adaptive_young_list_length(), "pre-condition");
tonyp@3119 690 assert(full_young_gcs(), "only call this for fully-young GCs");
tonyp@3119 691
tonyp@3119 692 // In case some edge-condition makes the desired max length too small...
tonyp@3119 693 if (desired_max_length <= desired_min_length) {
tonyp@3119 694 return desired_min_length;
tonyp@3119 695 }
tonyp@3119 696
tonyp@3119 697 // We'll adjust min_young_length and max_young_length not to include
tonyp@3119 698 // the already allocated young regions (i.e., so they reflect the
tonyp@3119 699 // min and max eden regions we'll allocate). The base_min_length
tonyp@3119 700 // will be reflected in the predictions by the
tonyp@3119 701 // survivor_regions_evac_time prediction.
tonyp@3119 702 assert(desired_min_length > base_min_length, "invariant");
tonyp@3119 703 size_t min_young_length = desired_min_length - base_min_length;
tonyp@3119 704 assert(desired_max_length > base_min_length, "invariant");
tonyp@3119 705 size_t max_young_length = desired_max_length - base_min_length;
tonyp@3119 706
tonyp@3119 707 double target_pause_time_ms = _mmu_tracker->max_gc_time() * 1000.0;
tonyp@3119 708 double survivor_regions_evac_time = predict_survivor_regions_evac_time();
tonyp@3119 709 size_t pending_cards = (size_t) get_new_prediction(_pending_cards_seq);
tonyp@3119 710 size_t adj_rs_lengths = rs_lengths + predict_rs_length_diff();
tonyp@3119 711 size_t scanned_cards = predict_young_card_num(adj_rs_lengths);
tonyp@3119 712 double base_time_ms =
tonyp@3119 713 predict_base_elapsed_time_ms(pending_cards, scanned_cards) +
tonyp@3119 714 survivor_regions_evac_time;
tonyp@3119 715 size_t available_free_regions = _free_regions_at_end_of_collection;
tonyp@3119 716 size_t base_free_regions = 0;
tonyp@3119 717 if (available_free_regions > _reserve_regions) {
tonyp@3119 718 base_free_regions = available_free_regions - _reserve_regions;
tonyp@3119 719 }
tonyp@3119 720
tonyp@3119 721 // Here, we will make sure that the shortest young length that
tonyp@3119 722 // makes sense fits within the target pause time.
tonyp@3119 723
tonyp@3119 724 if (predict_will_fit(min_young_length, base_time_ms,
tonyp@3119 725 base_free_regions, target_pause_time_ms)) {
tonyp@3119 726 // The shortest young length will fit into the target pause time;
tonyp@3119 727 // we'll now check whether the absolute maximum number of young
tonyp@3119 728 // regions will fit in the target pause time. If not, we'll do
tonyp@3119 729 // a binary search between min_young_length and max_young_length.
tonyp@3119 730 if (predict_will_fit(max_young_length, base_time_ms,
tonyp@3119 731 base_free_regions, target_pause_time_ms)) {
tonyp@3119 732 // The maximum young length will fit into the target pause time.
tonyp@3119 733 // We are done so set min young length to the maximum length (as
tonyp@3119 734 // the result is assumed to be returned in min_young_length).
tonyp@3119 735 min_young_length = max_young_length;
tonyp@3119 736 } else {
tonyp@3119 737 // The maximum possible number of young regions will not fit within
tonyp@3119 738 // the target pause time so we'll search for the optimal
tonyp@3119 739 // length. The loop invariants are:
tonyp@3119 740 //
tonyp@3119 741 // min_young_length < max_young_length
tonyp@3119 742 // min_young_length is known to fit into the target pause time
tonyp@3119 743 // max_young_length is known not to fit into the target pause time
tonyp@3119 744 //
tonyp@3119 745 // Going into the loop we know the above hold as we've just
tonyp@3119 746 // checked them. Every time around the loop we check whether
tonyp@3119 747 // the middle value between min_young_length and
tonyp@3119 748 // max_young_length fits into the target pause time. If it
tonyp@3119 749 // does, it becomes the new min. If it doesn't, it becomes
tonyp@3119 750 // the new max. This way we maintain the loop invariants.
tonyp@3119 751
tonyp@3119 752 assert(min_young_length < max_young_length, "invariant");
tonyp@3119 753 size_t diff = (max_young_length - min_young_length) / 2;
tonyp@3119 754 while (diff > 0) {
tonyp@3119 755 size_t young_length = min_young_length + diff;
tonyp@3119 756 if (predict_will_fit(young_length, base_time_ms,
tonyp@3119 757 base_free_regions, target_pause_time_ms)) {
tonyp@3119 758 min_young_length = young_length;
tonyp@3119 759 } else {
tonyp@3119 760 max_young_length = young_length;
tonyp@3119 761 }
tonyp@3119 762 assert(min_young_length < max_young_length, "invariant");
tonyp@3119 763 diff = (max_young_length - min_young_length) / 2;
tonyp@3119 764 }
tonyp@3119 765 // The results is min_young_length which, according to the
tonyp@3119 766 // loop invariants, should fit within the target pause time.
tonyp@3119 767
tonyp@3119 768 // These are the post-conditions of the binary search above:
tonyp@3119 769 assert(min_young_length < max_young_length,
tonyp@3119 770 "otherwise we should have discovered that max_young_length "
tonyp@3119 771 "fits into the pause target and not done the binary search");
tonyp@3119 772 assert(predict_will_fit(min_young_length, base_time_ms,
tonyp@3119 773 base_free_regions, target_pause_time_ms),
tonyp@3119 774 "min_young_length, the result of the binary search, should "
tonyp@3119 775 "fit into the pause target");
tonyp@3119 776 assert(!predict_will_fit(min_young_length + 1, base_time_ms,
tonyp@3119 777 base_free_regions, target_pause_time_ms),
tonyp@3119 778 "min_young_length, the result of the binary search, should be "
tonyp@3119 779 "optimal, so no larger length should fit into the pause target");
tonyp@3119 780 }
tonyp@3119 781 } else {
tonyp@3119 782 // Even the minimum length doesn't fit into the pause time
tonyp@3119 783 // target, return it as the result nevertheless.
tonyp@3119 784 }
tonyp@3119 785 return base_min_length + min_young_length;
ysr@777 786 }
ysr@777 787
apetrusenko@980 788 double G1CollectorPolicy::predict_survivor_regions_evac_time() {
apetrusenko@980 789 double survivor_regions_evac_time = 0.0;
apetrusenko@980 790 for (HeapRegion * r = _recorded_survivor_head;
apetrusenko@980 791 r != NULL && r != _recorded_survivor_tail->get_next_young_region();
apetrusenko@980 792 r = r->get_next_young_region()) {
apetrusenko@980 793 survivor_regions_evac_time += predict_region_elapsed_time_ms(r, true);
apetrusenko@980 794 }
apetrusenko@980 795 return survivor_regions_evac_time;
apetrusenko@980 796 }
apetrusenko@980 797
tonyp@3119 798 void G1CollectorPolicy::revise_young_list_target_length_if_necessary() {
ysr@777 799 guarantee( adaptive_young_list_length(), "should not call this otherwise" );
ysr@777 800
johnc@1829 801 size_t rs_lengths = _g1->young_list()->sampled_rs_lengths();
ysr@777 802 if (rs_lengths > _rs_lengths_prediction) {
ysr@777 803 // add 10% to avoid having to recalculate often
ysr@777 804 size_t rs_lengths_prediction = rs_lengths * 1100 / 1000;
tonyp@3119 805 update_young_list_target_length(rs_lengths_prediction);
ysr@777 806 }
ysr@777 807 }
ysr@777 808
tonyp@3119 809
tonyp@3119 810
ysr@777 811 HeapWord* G1CollectorPolicy::mem_allocate_work(size_t size,
ysr@777 812 bool is_tlab,
ysr@777 813 bool* gc_overhead_limit_was_exceeded) {
ysr@777 814 guarantee(false, "Not using this policy feature yet.");
ysr@777 815 return NULL;
ysr@777 816 }
ysr@777 817
ysr@777 818 // This method controls how a collector handles one or more
ysr@777 819 // of its generations being fully allocated.
ysr@777 820 HeapWord* G1CollectorPolicy::satisfy_failed_allocation(size_t size,
ysr@777 821 bool is_tlab) {
ysr@777 822 guarantee(false, "Not using this policy feature yet.");
ysr@777 823 return NULL;
ysr@777 824 }
ysr@777 825
ysr@777 826
ysr@777 827 #ifndef PRODUCT
ysr@777 828 bool G1CollectorPolicy::verify_young_ages() {
johnc@1829 829 HeapRegion* head = _g1->young_list()->first_region();
ysr@777 830 return
ysr@777 831 verify_young_ages(head, _short_lived_surv_rate_group);
ysr@777 832 // also call verify_young_ages on any additional surv rate groups
ysr@777 833 }
ysr@777 834
ysr@777 835 bool
ysr@777 836 G1CollectorPolicy::verify_young_ages(HeapRegion* head,
ysr@777 837 SurvRateGroup *surv_rate_group) {
ysr@777 838 guarantee( surv_rate_group != NULL, "pre-condition" );
ysr@777 839
ysr@777 840 const char* name = surv_rate_group->name();
ysr@777 841 bool ret = true;
ysr@777 842 int prev_age = -1;
ysr@777 843
ysr@777 844 for (HeapRegion* curr = head;
ysr@777 845 curr != NULL;
ysr@777 846 curr = curr->get_next_young_region()) {
ysr@777 847 SurvRateGroup* group = curr->surv_rate_group();
ysr@777 848 if (group == NULL && !curr->is_survivor()) {
ysr@777 849 gclog_or_tty->print_cr("## %s: encountered NULL surv_rate_group", name);
ysr@777 850 ret = false;
ysr@777 851 }
ysr@777 852
ysr@777 853 if (surv_rate_group == group) {
ysr@777 854 int age = curr->age_in_surv_rate_group();
ysr@777 855
ysr@777 856 if (age < 0) {
ysr@777 857 gclog_or_tty->print_cr("## %s: encountered negative age", name);
ysr@777 858 ret = false;
ysr@777 859 }
ysr@777 860
ysr@777 861 if (age <= prev_age) {
ysr@777 862 gclog_or_tty->print_cr("## %s: region ages are not strictly increasing "
ysr@777 863 "(%d, %d)", name, age, prev_age);
ysr@777 864 ret = false;
ysr@777 865 }
ysr@777 866 prev_age = age;
ysr@777 867 }
ysr@777 868 }
ysr@777 869
ysr@777 870 return ret;
ysr@777 871 }
ysr@777 872 #endif // PRODUCT
ysr@777 873
ysr@777 874 void G1CollectorPolicy::record_full_collection_start() {
ysr@777 875 _cur_collection_start_sec = os::elapsedTime();
ysr@777 876 // Release the future to-space so that it is available for compaction into.
ysr@777 877 _g1->set_full_collection();
ysr@777 878 }
ysr@777 879
ysr@777 880 void G1CollectorPolicy::record_full_collection_end() {
ysr@777 881 // Consider this like a collection pause for the purposes of allocation
ysr@777 882 // since last pause.
ysr@777 883 double end_sec = os::elapsedTime();
ysr@777 884 double full_gc_time_sec = end_sec - _cur_collection_start_sec;
ysr@777 885 double full_gc_time_ms = full_gc_time_sec * 1000.0;
ysr@777 886
ysr@777 887 _all_full_gc_times_ms->add(full_gc_time_ms);
ysr@777 888
tonyp@1030 889 update_recent_gc_times(end_sec, full_gc_time_ms);
ysr@777 890
ysr@777 891 _g1->clear_full_collection();
ysr@777 892
ysr@777 893 // "Nuke" the heuristics that control the fully/partially young GC
ysr@777 894 // transitions and make sure we start with fully young GCs after the
ysr@777 895 // Full GC.
ysr@777 896 set_full_young_gcs(true);
ysr@777 897 _last_full_young_gc = false;
ysr@777 898 _should_revert_to_full_young_gcs = false;
tonyp@1794 899 clear_initiate_conc_mark_if_possible();
tonyp@1794 900 clear_during_initial_mark_pause();
ysr@777 901 _known_garbage_bytes = 0;
ysr@777 902 _known_garbage_ratio = 0.0;
ysr@777 903 _in_marking_window = false;
ysr@777 904 _in_marking_window_im = false;
ysr@777 905
ysr@777 906 _short_lived_surv_rate_group->start_adding_regions();
ysr@777 907 // also call this on any additional surv rate groups
ysr@777 908
apetrusenko@980 909 record_survivor_regions(0, NULL, NULL);
apetrusenko@980 910
ysr@777 911 _prev_region_num_young = _region_num_young;
ysr@777 912 _prev_region_num_tenured = _region_num_tenured;
ysr@777 913
ysr@777 914 _free_regions_at_end_of_collection = _g1->free_regions();
apetrusenko@980 915 // Reset survivors SurvRateGroup.
apetrusenko@980 916 _survivor_surv_rate_group->reset();
tonyp@3119 917 update_young_list_target_length();
tonyp@3209 918 _collectionSetChooser->updateAfterFullCollection();
tonyp@2315 919 }
ysr@777 920
ysr@777 921 void G1CollectorPolicy::record_stop_world_start() {
ysr@777 922 _stop_world_start = os::elapsedTime();
ysr@777 923 }
ysr@777 924
ysr@777 925 void G1CollectorPolicy::record_collection_pause_start(double start_time_sec,
ysr@777 926 size_t start_used) {
ysr@777 927 if (PrintGCDetails) {
ysr@777 928 gclog_or_tty->stamp(PrintGCTimeStamps);
ysr@777 929 gclog_or_tty->print("[GC pause");
brutisso@3065 930 gclog_or_tty->print(" (%s)", full_young_gcs() ? "young" : "partial");
ysr@777 931 }
ysr@777 932
tonyp@3119 933 // We only need to do this here as the policy will only be applied
tonyp@3119 934 // to the GC we're about to start. so, no point is calculating this
tonyp@3119 935 // every time we calculate / recalculate the target young length.
tonyp@3119 936 update_survivors_policy();
tonyp@3119 937
tonyp@2315 938 assert(_g1->used() == _g1->recalculate_used(),
tonyp@2315 939 err_msg("sanity, used: "SIZE_FORMAT" recalculate_used: "SIZE_FORMAT,
tonyp@2315 940 _g1->used(), _g1->recalculate_used()));
ysr@777 941
ysr@777 942 double s_w_t_ms = (start_time_sec - _stop_world_start) * 1000.0;
ysr@777 943 _all_stop_world_times_ms->add(s_w_t_ms);
ysr@777 944 _stop_world_start = 0.0;
ysr@777 945
ysr@777 946 _cur_collection_start_sec = start_time_sec;
ysr@777 947 _cur_collection_pause_used_at_start_bytes = start_used;
ysr@777 948 _cur_collection_pause_used_regions_at_start = _g1->used_regions();
ysr@777 949 _pending_cards = _g1->pending_card_num();
ysr@777 950 _max_pending_cards = _g1->max_pending_card_num();
ysr@777 951
ysr@777 952 _bytes_in_collection_set_before_gc = 0;
tonyp@3028 953 _bytes_copied_during_gc = 0;
ysr@777 954
tonyp@2961 955 YoungList* young_list = _g1->young_list();
tonyp@2961 956 _eden_bytes_before_gc = young_list->eden_used_bytes();
tonyp@2961 957 _survivor_bytes_before_gc = young_list->survivor_used_bytes();
tonyp@2961 958 _capacity_before_gc = _g1->capacity();
tonyp@2961 959
ysr@777 960 #ifdef DEBUG
ysr@777 961 // initialise these to something well known so that we can spot
ysr@777 962 // if they are not set properly
ysr@777 963
ysr@777 964 for (int i = 0; i < _parallel_gc_threads; ++i) {
tonyp@1966 965 _par_last_gc_worker_start_times_ms[i] = -1234.0;
tonyp@1966 966 _par_last_ext_root_scan_times_ms[i] = -1234.0;
tonyp@1966 967 _par_last_mark_stack_scan_times_ms[i] = -1234.0;
tonyp@1966 968 _par_last_update_rs_times_ms[i] = -1234.0;
tonyp@1966 969 _par_last_update_rs_processed_buffers[i] = -1234.0;
tonyp@1966 970 _par_last_scan_rs_times_ms[i] = -1234.0;
tonyp@1966 971 _par_last_obj_copy_times_ms[i] = -1234.0;
tonyp@1966 972 _par_last_termination_times_ms[i] = -1234.0;
tonyp@1966 973 _par_last_termination_attempts[i] = -1234.0;
tonyp@1966 974 _par_last_gc_worker_end_times_ms[i] = -1234.0;
brutisso@2712 975 _par_last_gc_worker_times_ms[i] = -1234.0;
johnc@3219 976 _par_last_gc_worker_other_times_ms[i] = -1234.0;
ysr@777 977 }
ysr@777 978 #endif
ysr@777 979
ysr@777 980 for (int i = 0; i < _aux_num; ++i) {
ysr@777 981 _cur_aux_times_ms[i] = 0.0;
ysr@777 982 _cur_aux_times_set[i] = false;
ysr@777 983 }
ysr@777 984
johnc@3219 985 // These are initialized to zero here and they are set during
johnc@3219 986 // the evacuation pause if marking is in progress.
johnc@3219 987 _cur_satb_drain_time_ms = 0.0;
johnc@3219 988 _last_satb_drain_processed_buffers = 0;
ysr@777 989
brutisso@3065 990 _last_young_gc_full = false;
ysr@777 991
ysr@777 992 // do that for any other surv rate groups
ysr@777 993 _short_lived_surv_rate_group->stop_adding_regions();
tonyp@1717 994 _survivors_age_table.clear();
apetrusenko@980 995
ysr@777 996 assert( verify_young_ages(), "region age verification" );
ysr@777 997 }
ysr@777 998
ysr@777 999 void G1CollectorPolicy::record_mark_closure_time(double mark_closure_time_ms) {
ysr@777 1000 _mark_closure_time_ms = mark_closure_time_ms;
ysr@777 1001 }
ysr@777 1002
brutisso@3065 1003 void G1CollectorPolicy::record_concurrent_mark_init_end(double
ysr@777 1004 mark_init_elapsed_time_ms) {
ysr@777 1005 _during_marking = true;
tonyp@1794 1006 assert(!initiate_conc_mark_if_possible(), "we should have cleared it by now");
tonyp@1794 1007 clear_during_initial_mark_pause();
ysr@777 1008 _cur_mark_stop_world_time_ms = mark_init_elapsed_time_ms;
ysr@777 1009 }
ysr@777 1010
ysr@777 1011 void G1CollectorPolicy::record_concurrent_mark_remark_start() {
ysr@777 1012 _mark_remark_start_sec = os::elapsedTime();
ysr@777 1013 _during_marking = false;
ysr@777 1014 }
ysr@777 1015
ysr@777 1016 void G1CollectorPolicy::record_concurrent_mark_remark_end() {
ysr@777 1017 double end_time_sec = os::elapsedTime();
ysr@777 1018 double elapsed_time_ms = (end_time_sec - _mark_remark_start_sec)*1000.0;
ysr@777 1019 _concurrent_mark_remark_times_ms->add(elapsed_time_ms);
ysr@777 1020 _cur_mark_stop_world_time_ms += elapsed_time_ms;
ysr@777 1021 _prev_collection_pause_end_ms += elapsed_time_ms;
ysr@777 1022
ysr@777 1023 _mmu_tracker->add_pause(_mark_remark_start_sec, end_time_sec, true);
ysr@777 1024 }
ysr@777 1025
ysr@777 1026 void G1CollectorPolicy::record_concurrent_mark_cleanup_start() {
ysr@777 1027 _mark_cleanup_start_sec = os::elapsedTime();
ysr@777 1028 }
ysr@777 1029
tonyp@3209 1030 void G1CollectorPolicy::record_concurrent_mark_cleanup_completed() {
brutisso@3065 1031 _should_revert_to_full_young_gcs = false;
brutisso@3065 1032 _last_full_young_gc = true;
brutisso@3065 1033 _in_marking_window = false;
ysr@777 1034 }
ysr@777 1035
ysr@777 1036 void G1CollectorPolicy::record_concurrent_pause() {
ysr@777 1037 if (_stop_world_start > 0.0) {
ysr@777 1038 double yield_ms = (os::elapsedTime() - _stop_world_start) * 1000.0;
ysr@777 1039 _all_yield_times_ms->add(yield_ms);
ysr@777 1040 }
ysr@777 1041 }
ysr@777 1042
ysr@777 1043 void G1CollectorPolicy::record_concurrent_pause_end() {
ysr@777 1044 }
ysr@777 1045
ysr@777 1046 template<class T>
ysr@777 1047 T sum_of(T* sum_arr, int start, int n, int N) {
ysr@777 1048 T sum = (T)0;
ysr@777 1049 for (int i = 0; i < n; i++) {
ysr@777 1050 int j = (start + i) % N;
ysr@777 1051 sum += sum_arr[j];
ysr@777 1052 }
ysr@777 1053 return sum;
ysr@777 1054 }
ysr@777 1055
tonyp@1966 1056 void G1CollectorPolicy::print_par_stats(int level,
tonyp@1966 1057 const char* str,
brutisso@2712 1058 double* data) {
ysr@777 1059 double min = data[0], max = data[0];
ysr@777 1060 double total = 0.0;
brutisso@2645 1061 LineBuffer buf(level);
brutisso@2645 1062 buf.append("[%s (ms):", str);
ysr@777 1063 for (uint i = 0; i < ParallelGCThreads; ++i) {
ysr@777 1064 double val = data[i];
ysr@777 1065 if (val < min)
ysr@777 1066 min = val;
ysr@777 1067 if (val > max)
ysr@777 1068 max = val;
ysr@777 1069 total += val;
brutisso@2645 1070 buf.append(" %3.1lf", val);
ysr@777 1071 }
brutisso@2712 1072 buf.append_and_print_cr("");
brutisso@2712 1073 double avg = total / (double) ParallelGCThreads;
brutisso@2712 1074 buf.append_and_print_cr(" Avg: %5.1lf, Min: %5.1lf, Max: %5.1lf, Diff: %5.1lf]",
brutisso@2712 1075 avg, min, max, max - min);
ysr@777 1076 }
ysr@777 1077
tonyp@1966 1078 void G1CollectorPolicy::print_par_sizes(int level,
tonyp@1966 1079 const char* str,
brutisso@2712 1080 double* data) {
ysr@777 1081 double min = data[0], max = data[0];
ysr@777 1082 double total = 0.0;
brutisso@2645 1083 LineBuffer buf(level);
brutisso@2645 1084 buf.append("[%s :", str);
ysr@777 1085 for (uint i = 0; i < ParallelGCThreads; ++i) {
ysr@777 1086 double val = data[i];
ysr@777 1087 if (val < min)
ysr@777 1088 min = val;
ysr@777 1089 if (val > max)
ysr@777 1090 max = val;
ysr@777 1091 total += val;
brutisso@2645 1092 buf.append(" %d", (int) val);
ysr@777 1093 }
brutisso@2712 1094 buf.append_and_print_cr("");
brutisso@2712 1095 double avg = total / (double) ParallelGCThreads;
brutisso@2712 1096 buf.append_and_print_cr(" Sum: %d, Avg: %d, Min: %d, Max: %d, Diff: %d]",
brutisso@2712 1097 (int)total, (int)avg, (int)min, (int)max, (int)max - (int)min);
ysr@777 1098 }
ysr@777 1099
johnc@3219 1100 void G1CollectorPolicy::print_stats(int level,
johnc@3219 1101 const char* str,
johnc@3219 1102 double value) {
brutisso@2645 1103 LineBuffer(level).append_and_print_cr("[%s: %5.1lf ms]", str, value);
ysr@777 1104 }
ysr@777 1105
johnc@3219 1106 void G1CollectorPolicy::print_stats(int level,
johnc@3219 1107 const char* str,
johnc@3219 1108 int value) {
brutisso@2645 1109 LineBuffer(level).append_and_print_cr("[%s: %d]", str, value);
ysr@777 1110 }
ysr@777 1111
johnc@3219 1112 double G1CollectorPolicy::avg_value(double* data) {
jmasa@2188 1113 if (G1CollectedHeap::use_parallel_gc_threads()) {
ysr@777 1114 double ret = 0.0;
johnc@3219 1115 for (uint i = 0; i < ParallelGCThreads; ++i) {
ysr@777 1116 ret += data[i];
johnc@3219 1117 }
ysr@777 1118 return ret / (double) ParallelGCThreads;
ysr@777 1119 } else {
ysr@777 1120 return data[0];
ysr@777 1121 }
ysr@777 1122 }
ysr@777 1123
johnc@3219 1124 double G1CollectorPolicy::max_value(double* data) {
jmasa@2188 1125 if (G1CollectedHeap::use_parallel_gc_threads()) {
ysr@777 1126 double ret = data[0];
johnc@3219 1127 for (uint i = 1; i < ParallelGCThreads; ++i) {
johnc@3219 1128 if (data[i] > ret) {
ysr@777 1129 ret = data[i];
johnc@3219 1130 }
johnc@3219 1131 }
ysr@777 1132 return ret;
ysr@777 1133 } else {
ysr@777 1134 return data[0];
ysr@777 1135 }
ysr@777 1136 }
ysr@777 1137
johnc@3219 1138 double G1CollectorPolicy::sum_of_values(double* data) {
jmasa@2188 1139 if (G1CollectedHeap::use_parallel_gc_threads()) {
ysr@777 1140 double sum = 0.0;
johnc@3219 1141 for (uint i = 0; i < ParallelGCThreads; i++) {
ysr@777 1142 sum += data[i];
johnc@3219 1143 }
ysr@777 1144 return sum;
ysr@777 1145 } else {
ysr@777 1146 return data[0];
ysr@777 1147 }
ysr@777 1148 }
ysr@777 1149
johnc@3219 1150 double G1CollectorPolicy::max_sum(double* data1, double* data2) {
ysr@777 1151 double ret = data1[0] + data2[0];
ysr@777 1152
jmasa@2188 1153 if (G1CollectedHeap::use_parallel_gc_threads()) {
ysr@777 1154 for (uint i = 1; i < ParallelGCThreads; ++i) {
ysr@777 1155 double data = data1[i] + data2[i];
johnc@3219 1156 if (data > ret) {
ysr@777 1157 ret = data;
johnc@3219 1158 }
ysr@777 1159 }
ysr@777 1160 }
ysr@777 1161 return ret;
ysr@777 1162 }
ysr@777 1163
ysr@777 1164 // Anything below that is considered to be zero
ysr@777 1165 #define MIN_TIMER_GRANULARITY 0.0000001
ysr@777 1166
tonyp@2062 1167 void G1CollectorPolicy::record_collection_pause_end() {
ysr@777 1168 double end_time_sec = os::elapsedTime();
ysr@777 1169 double elapsed_ms = _last_pause_time_ms;
jmasa@2188 1170 bool parallel = G1CollectedHeap::use_parallel_gc_threads();
ysr@777 1171 size_t rs_size =
ysr@777 1172 _cur_collection_pause_used_regions_at_start - collection_set_size();
ysr@777 1173 size_t cur_used_bytes = _g1->used();
ysr@777 1174 assert(cur_used_bytes == _g1->recalculate_used(), "It should!");
ysr@777 1175 bool last_pause_included_initial_mark = false;
tonyp@2062 1176 bool update_stats = !_g1->evacuation_failed();
ysr@777 1177
ysr@777 1178 #ifndef PRODUCT
ysr@777 1179 if (G1YoungSurvRateVerbose) {
ysr@777 1180 gclog_or_tty->print_cr("");
ysr@777 1181 _short_lived_surv_rate_group->print();
ysr@777 1182 // do that for any other surv rate groups too
ysr@777 1183 }
ysr@777 1184 #endif // PRODUCT
ysr@777 1185
brutisso@3065 1186 last_pause_included_initial_mark = during_initial_mark_pause();
brutisso@3065 1187 if (last_pause_included_initial_mark)
brutisso@3065 1188 record_concurrent_mark_init_end(0.0);
brutisso@3065 1189
tonyp@3114 1190 size_t marking_initiating_used_threshold =
brutisso@3065 1191 (_g1->capacity() / 100) * InitiatingHeapOccupancyPercent;
brutisso@3065 1192
brutisso@3065 1193 if (!_g1->mark_in_progress() && !_last_full_young_gc) {
brutisso@3065 1194 assert(!last_pause_included_initial_mark, "invariant");
tonyp@3114 1195 if (cur_used_bytes > marking_initiating_used_threshold) {
tonyp@3114 1196 if (cur_used_bytes > _prev_collection_pause_used_at_end_bytes) {
tonyp@1794 1197 assert(!during_initial_mark_pause(), "we should not see this here");
tonyp@1794 1198
tonyp@3114 1199 ergo_verbose3(ErgoConcCycles,
tonyp@3114 1200 "request concurrent cycle initiation",
tonyp@3114 1201 ergo_format_reason("occupancy higher than threshold")
tonyp@3114 1202 ergo_format_byte("occupancy")
tonyp@3114 1203 ergo_format_byte_perc("threshold"),
tonyp@3114 1204 cur_used_bytes,
tonyp@3114 1205 marking_initiating_used_threshold,
tonyp@3114 1206 (double) InitiatingHeapOccupancyPercent);
tonyp@3114 1207
tonyp@1794 1208 // Note: this might have already been set, if during the last
tonyp@1794 1209 // pause we decided to start a cycle but at the beginning of
tonyp@1794 1210 // this pause we decided to postpone it. That's OK.
tonyp@1794 1211 set_initiate_conc_mark_if_possible();
tonyp@3114 1212 } else {
tonyp@3114 1213 ergo_verbose2(ErgoConcCycles,
tonyp@3114 1214 "do not request concurrent cycle initiation",
tonyp@3114 1215 ergo_format_reason("occupancy lower than previous occupancy")
tonyp@3114 1216 ergo_format_byte("occupancy")
tonyp@3114 1217 ergo_format_byte("previous occupancy"),
tonyp@3114 1218 cur_used_bytes,
tonyp@3114 1219 _prev_collection_pause_used_at_end_bytes);
tonyp@3114 1220 }
ysr@777 1221 }
ysr@777 1222 }
ysr@777 1223
brutisso@3065 1224 _prev_collection_pause_used_at_end_bytes = cur_used_bytes;
brutisso@3065 1225
ysr@777 1226 _mmu_tracker->add_pause(end_time_sec - elapsed_ms/1000.0,
ysr@777 1227 end_time_sec, false);
ysr@777 1228
ysr@777 1229 guarantee(_cur_collection_pause_used_regions_at_start >=
ysr@777 1230 collection_set_size(),
ysr@777 1231 "Negative RS size?");
ysr@777 1232
ysr@777 1233 // This assert is exempted when we're doing parallel collection pauses,
ysr@777 1234 // because the fragmentation caused by the parallel GC allocation buffers
ysr@777 1235 // can lead to more memory being used during collection than was used
ysr@777 1236 // before. Best leave this out until the fragmentation problem is fixed.
ysr@777 1237 // Pauses in which evacuation failed can also lead to negative
ysr@777 1238 // collections, since no space is reclaimed from a region containing an
ysr@777 1239 // object whose evacuation failed.
ysr@777 1240 // Further, we're now always doing parallel collection. But I'm still
ysr@777 1241 // leaving this here as a placeholder for a more precise assertion later.
ysr@777 1242 // (DLD, 10/05.)
ysr@777 1243 assert((true || parallel) // Always using GC LABs now.
ysr@777 1244 || _g1->evacuation_failed()
ysr@777 1245 || _cur_collection_pause_used_at_start_bytes >= cur_used_bytes,
ysr@777 1246 "Negative collection");
ysr@777 1247
ysr@777 1248 size_t freed_bytes =
ysr@777 1249 _cur_collection_pause_used_at_start_bytes - cur_used_bytes;
ysr@777 1250 size_t surviving_bytes = _collection_set_bytes_used_before - freed_bytes;
johnc@1829 1251
ysr@777 1252 double survival_fraction =
ysr@777 1253 (double)surviving_bytes/
ysr@777 1254 (double)_collection_set_bytes_used_before;
ysr@777 1255
ysr@777 1256 _n_pauses++;
ysr@777 1257
johnc@3219 1258 // These values are used to update the summary information that is
johnc@3219 1259 // displayed when TraceGen0Time is enabled, and are output as part
johnc@3219 1260 // of the PrintGCDetails output, in the non-parallel case.
johnc@3219 1261
johnc@3021 1262 double ext_root_scan_time = avg_value(_par_last_ext_root_scan_times_ms);
johnc@3021 1263 double mark_stack_scan_time = avg_value(_par_last_mark_stack_scan_times_ms);
johnc@3021 1264 double update_rs_time = avg_value(_par_last_update_rs_times_ms);
johnc@3021 1265 double update_rs_processed_buffers =
johnc@3021 1266 sum_of_values(_par_last_update_rs_processed_buffers);
johnc@3021 1267 double scan_rs_time = avg_value(_par_last_scan_rs_times_ms);
johnc@3021 1268 double obj_copy_time = avg_value(_par_last_obj_copy_times_ms);
johnc@3021 1269 double termination_time = avg_value(_par_last_termination_times_ms);
johnc@3021 1270
johnc@3219 1271 double known_time = ext_root_scan_time +
johnc@3219 1272 mark_stack_scan_time +
johnc@3219 1273 update_rs_time +
johnc@3219 1274 scan_rs_time +
johnc@3219 1275 obj_copy_time;
johnc@3219 1276
johnc@3219 1277 double other_time_ms = elapsed_ms;
johnc@3219 1278
johnc@3219 1279 // Subtract the SATB drain time. It's initialized to zero at the
johnc@3219 1280 // start of the pause and is updated during the pause if marking
johnc@3219 1281 // is in progress.
johnc@3219 1282 other_time_ms -= _cur_satb_drain_time_ms;
johnc@3219 1283
johnc@3219 1284 if (parallel) {
johnc@3219 1285 other_time_ms -= _cur_collection_par_time_ms;
johnc@3219 1286 } else {
johnc@3219 1287 other_time_ms -= known_time;
johnc@3219 1288 }
johnc@3219 1289
johnc@3219 1290 // Subtract the time taken to clean the card table from the
johnc@3219 1291 // current value of "other time"
johnc@3219 1292 other_time_ms -= _cur_clear_ct_time_ms;
johnc@3219 1293
johnc@3219 1294 // TraceGen0Time and TraceGen1Time summary info updating.
johnc@3219 1295 _all_pause_times_ms->add(elapsed_ms);
johnc@3021 1296
tonyp@1030 1297 if (update_stats) {
johnc@3021 1298 _recent_rs_scan_times_ms->add(scan_rs_time);
ysr@777 1299 _recent_pause_times_ms->add(elapsed_ms);
ysr@777 1300 _recent_rs_sizes->add(rs_size);
ysr@777 1301
johnc@3219 1302 _summary->record_total_time_ms(elapsed_ms);
johnc@3219 1303 _summary->record_other_time_ms(other_time_ms);
johnc@3219 1304
johnc@3219 1305 MainBodySummary* body_summary = _summary->main_body_summary();
johnc@3219 1306 assert(body_summary != NULL, "should not be null!");
johnc@3219 1307
johnc@3219 1308 // This will be non-zero iff marking is currently in progress (i.e.
johnc@3219 1309 // _g1->mark_in_progress() == true) and the currrent pause was not
johnc@3219 1310 // an initial mark pause. Since the body_summary items are NumberSeqs,
johnc@3219 1311 // however, they have to be consistent and updated in lock-step with
johnc@3219 1312 // each other. Therefore we unconditionally record the SATB drain
johnc@3219 1313 // time - even if it's zero.
johnc@3219 1314 body_summary->record_satb_drain_time_ms(_cur_satb_drain_time_ms);
johnc@3021 1315
johnc@3021 1316 body_summary->record_ext_root_scan_time_ms(ext_root_scan_time);
johnc@3021 1317 body_summary->record_mark_stack_scan_time_ms(mark_stack_scan_time);
johnc@3021 1318 body_summary->record_update_rs_time_ms(update_rs_time);
johnc@3021 1319 body_summary->record_scan_rs_time_ms(scan_rs_time);
johnc@3021 1320 body_summary->record_obj_copy_time_ms(obj_copy_time);
johnc@3219 1321
johnc@3021 1322 if (parallel) {
johnc@3021 1323 body_summary->record_parallel_time_ms(_cur_collection_par_time_ms);
johnc@3021 1324 body_summary->record_termination_time_ms(termination_time);
johnc@3219 1325
johnc@3219 1326 double parallel_known_time = known_time + termination_time;
johnc@3219 1327 double parallel_other_time = _cur_collection_par_time_ms - parallel_known_time;
johnc@3021 1328 body_summary->record_parallel_other_time_ms(parallel_other_time);
johnc@3021 1329 }
johnc@3219 1330
johnc@3021 1331 body_summary->record_mark_closure_time_ms(_mark_closure_time_ms);
johnc@3219 1332 body_summary->record_clear_ct_time_ms(_cur_clear_ct_time_ms);
johnc@3021 1333
ysr@777 1334 // We exempt parallel collection from this check because Alloc Buffer
ysr@777 1335 // fragmentation can produce negative collections. Same with evac
ysr@777 1336 // failure.
ysr@777 1337 // Further, we're now always doing parallel collection. But I'm still
ysr@777 1338 // leaving this here as a placeholder for a more precise assertion later.
ysr@777 1339 // (DLD, 10/05.
ysr@777 1340 assert((true || parallel)
ysr@777 1341 || _g1->evacuation_failed()
ysr@777 1342 || surviving_bytes <= _collection_set_bytes_used_before,
ysr@777 1343 "Or else negative collection!");
johnc@3219 1344
ysr@777 1345 _recent_CS_bytes_used_before->add(_collection_set_bytes_used_before);
ysr@777 1346 _recent_CS_bytes_surviving->add(surviving_bytes);
ysr@777 1347
ysr@777 1348 // this is where we update the allocation rate of the application
ysr@777 1349 double app_time_ms =
ysr@777 1350 (_cur_collection_start_sec * 1000.0 - _prev_collection_pause_end_ms);
ysr@777 1351 if (app_time_ms < MIN_TIMER_GRANULARITY) {
ysr@777 1352 // This usually happens due to the timer not having the required
ysr@777 1353 // granularity. Some Linuxes are the usual culprits.
ysr@777 1354 // We'll just set it to something (arbitrarily) small.
ysr@777 1355 app_time_ms = 1.0;
ysr@777 1356 }
ysr@777 1357 size_t regions_allocated =
ysr@777 1358 (_region_num_young - _prev_region_num_young) +
ysr@777 1359 (_region_num_tenured - _prev_region_num_tenured);
ysr@777 1360 double alloc_rate_ms = (double) regions_allocated / app_time_ms;
ysr@777 1361 _alloc_rate_ms_seq->add(alloc_rate_ms);
ysr@777 1362 _prev_region_num_young = _region_num_young;
ysr@777 1363 _prev_region_num_tenured = _region_num_tenured;
ysr@777 1364
ysr@777 1365 double interval_ms =
ysr@777 1366 (end_time_sec - _recent_prev_end_times_for_all_gcs_sec->oldest()) * 1000.0;
ysr@777 1367 update_recent_gc_times(end_time_sec, elapsed_ms);
ysr@777 1368 _recent_avg_pause_time_ratio = _recent_gc_times_ms->sum()/interval_ms;
ysr@1521 1369 if (recent_avg_pause_time_ratio() < 0.0 ||
ysr@1521 1370 (recent_avg_pause_time_ratio() - 1.0 > 0.0)) {
ysr@1521 1371 #ifndef PRODUCT
ysr@1521 1372 // Dump info to allow post-facto debugging
ysr@1521 1373 gclog_or_tty->print_cr("recent_avg_pause_time_ratio() out of bounds");
ysr@1521 1374 gclog_or_tty->print_cr("-------------------------------------------");
ysr@1521 1375 gclog_or_tty->print_cr("Recent GC Times (ms):");
ysr@1521 1376 _recent_gc_times_ms->dump();
ysr@1521 1377 gclog_or_tty->print_cr("(End Time=%3.3f) Recent GC End Times (s):", end_time_sec);
ysr@1521 1378 _recent_prev_end_times_for_all_gcs_sec->dump();
ysr@1521 1379 gclog_or_tty->print_cr("GC = %3.3f, Interval = %3.3f, Ratio = %3.3f",
ysr@1521 1380 _recent_gc_times_ms->sum(), interval_ms, recent_avg_pause_time_ratio());
ysr@1522 1381 // In debug mode, terminate the JVM if the user wants to debug at this point.
ysr@1522 1382 assert(!G1FailOnFPError, "Debugging data for CR 6898948 has been dumped above");
ysr@1522 1383 #endif // !PRODUCT
ysr@1522 1384 // Clip ratio between 0.0 and 1.0, and continue. This will be fixed in
ysr@1522 1385 // CR 6902692 by redoing the manner in which the ratio is incrementally computed.
ysr@1521 1386 if (_recent_avg_pause_time_ratio < 0.0) {
ysr@1521 1387 _recent_avg_pause_time_ratio = 0.0;
ysr@1521 1388 } else {
ysr@1521 1389 assert(_recent_avg_pause_time_ratio - 1.0 > 0.0, "Ctl-point invariant");
ysr@1521 1390 _recent_avg_pause_time_ratio = 1.0;
ysr@1521 1391 }
ysr@1521 1392 }
ysr@777 1393 }
ysr@777 1394
johnc@3219 1395 for (int i = 0; i < _aux_num; ++i) {
johnc@3219 1396 if (_cur_aux_times_set[i]) {
johnc@3219 1397 _all_aux_times_ms[i].add(_cur_aux_times_ms[i]);
johnc@3219 1398 }
johnc@3219 1399 }
johnc@3219 1400
johnc@3219 1401
ysr@777 1402 if (G1PolicyVerbose > 1) {
ysr@777 1403 gclog_or_tty->print_cr(" Recording collection pause(%d)", _n_pauses);
ysr@777 1404 }
ysr@777 1405
ysr@777 1406 if (G1PolicyVerbose > 1) {
ysr@777 1407 gclog_or_tty->print_cr(" ET: %10.6f ms (avg: %10.6f ms)\n"
ysr@777 1408 " ET-RS: %10.6f ms (avg: %10.6f ms)\n"
ysr@777 1409 " |RS|: " SIZE_FORMAT,
ysr@777 1410 elapsed_ms, recent_avg_time_for_pauses_ms(),
johnc@3021 1411 scan_rs_time, recent_avg_time_for_rs_scan_ms(),
ysr@777 1412 rs_size);
ysr@777 1413
ysr@777 1414 gclog_or_tty->print_cr(" Used at start: " SIZE_FORMAT"K"
ysr@777 1415 " At end " SIZE_FORMAT "K\n"
ysr@777 1416 " garbage : " SIZE_FORMAT "K"
ysr@777 1417 " of " SIZE_FORMAT "K\n"
ysr@777 1418 " survival : %6.2f%% (%6.2f%% avg)",
ysr@777 1419 _cur_collection_pause_used_at_start_bytes/K,
ysr@777 1420 _g1->used()/K, freed_bytes/K,
ysr@777 1421 _collection_set_bytes_used_before/K,
ysr@777 1422 survival_fraction*100.0,
ysr@777 1423 recent_avg_survival_fraction()*100.0);
ysr@777 1424 gclog_or_tty->print_cr(" Recent %% gc pause time: %6.2f",
ysr@777 1425 recent_avg_pause_time_ratio() * 100.0);
ysr@777 1426 }
ysr@777 1427
johnc@3219 1428 // PrintGCDetails output
ysr@777 1429 if (PrintGCDetails) {
johnc@3219 1430 bool print_marking_info =
johnc@3219 1431 _g1->mark_in_progress() && !last_pause_included_initial_mark;
johnc@3219 1432
tonyp@2062 1433 gclog_or_tty->print_cr("%s, %1.8lf secs]",
ysr@777 1434 (last_pause_included_initial_mark) ? " (initial-mark)" : "",
ysr@777 1435 elapsed_ms / 1000.0);
ysr@777 1436
johnc@3219 1437 if (print_marking_info) {
tonyp@2062 1438 print_stats(1, "SATB Drain Time", _cur_satb_drain_time_ms);
tonyp@2062 1439 print_stats(2, "Processed Buffers", _last_satb_drain_processed_buffers);
tonyp@2062 1440 }
johnc@3219 1441
tonyp@2062 1442 if (parallel) {
tonyp@2062 1443 print_stats(1, "Parallel Time", _cur_collection_par_time_ms);
johnc@3219 1444 print_par_stats(2, "GC Worker Start", _par_last_gc_worker_start_times_ms);
johnc@3219 1445 print_par_stats(2, "Ext Root Scanning", _par_last_ext_root_scan_times_ms);
johnc@3219 1446 if (print_marking_info) {
johnc@3219 1447 print_par_stats(2, "Mark Stack Scanning", _par_last_mark_stack_scan_times_ms);
johnc@3219 1448 }
tonyp@2062 1449 print_par_stats(2, "Update RS", _par_last_update_rs_times_ms);
brutisso@2712 1450 print_par_sizes(3, "Processed Buffers", _par_last_update_rs_processed_buffers);
tonyp@2062 1451 print_par_stats(2, "Scan RS", _par_last_scan_rs_times_ms);
tonyp@2062 1452 print_par_stats(2, "Object Copy", _par_last_obj_copy_times_ms);
tonyp@2062 1453 print_par_stats(2, "Termination", _par_last_termination_times_ms);
brutisso@2712 1454 print_par_sizes(3, "Termination Attempts", _par_last_termination_attempts);
johnc@3219 1455 print_par_stats(2, "GC Worker End", _par_last_gc_worker_end_times_ms);
brutisso@2712 1456
brutisso@2712 1457 for (int i = 0; i < _parallel_gc_threads; i++) {
brutisso@2712 1458 _par_last_gc_worker_times_ms[i] = _par_last_gc_worker_end_times_ms[i] - _par_last_gc_worker_start_times_ms[i];
johnc@3219 1459
johnc@3219 1460 double worker_known_time = _par_last_ext_root_scan_times_ms[i] +
johnc@3219 1461 _par_last_mark_stack_scan_times_ms[i] +
johnc@3219 1462 _par_last_update_rs_times_ms[i] +
johnc@3219 1463 _par_last_scan_rs_times_ms[i] +
johnc@3219 1464 _par_last_obj_copy_times_ms[i] +
johnc@3219 1465 _par_last_termination_times_ms[i];
johnc@3219 1466
johnc@3219 1467 _par_last_gc_worker_other_times_ms[i] = _cur_collection_par_time_ms - worker_known_time;
brutisso@2712 1468 }
johnc@3219 1469 print_par_stats(2, "GC Worker", _par_last_gc_worker_times_ms);
johnc@3219 1470 print_par_stats(2, "GC Worker Other", _par_last_gc_worker_other_times_ms);
tonyp@2062 1471 } else {
johnc@3219 1472 print_stats(1, "Ext Root Scanning", ext_root_scan_time);
johnc@3219 1473 if (print_marking_info) {
johnc@3219 1474 print_stats(1, "Mark Stack Scanning", mark_stack_scan_time);
johnc@3219 1475 }
tonyp@2062 1476 print_stats(1, "Update RS", update_rs_time);
johnc@3219 1477 print_stats(2, "Processed Buffers", (int)update_rs_processed_buffers);
tonyp@2062 1478 print_stats(1, "Scan RS", scan_rs_time);
tonyp@2062 1479 print_stats(1, "Object Copying", obj_copy_time);
ysr@777 1480 }
johnc@3219 1481 print_stats(1, "Clear CT", _cur_clear_ct_time_ms);
johnc@1325 1482 #ifndef PRODUCT
johnc@1325 1483 print_stats(1, "Cur Clear CC", _cur_clear_cc_time_ms);
johnc@1325 1484 print_stats(1, "Cum Clear CC", _cum_clear_cc_time_ms);
johnc@1325 1485 print_stats(1, "Min Clear CC", _min_clear_cc_time_ms);
johnc@1325 1486 print_stats(1, "Max Clear CC", _max_clear_cc_time_ms);
johnc@1325 1487 if (_num_cc_clears > 0) {
johnc@1325 1488 print_stats(1, "Avg Clear CC", _cum_clear_cc_time_ms / ((double)_num_cc_clears));
johnc@1325 1489 }
johnc@1325 1490 #endif
ysr@777 1491 print_stats(1, "Other", other_time_ms);
johnc@1829 1492 print_stats(2, "Choose CSet", _recorded_young_cset_choice_time_ms);
johnc@3175 1493 print_stats(2, "Ref Proc", _cur_ref_proc_time_ms);
johnc@3175 1494 print_stats(2, "Ref Enq", _cur_ref_enq_time_ms);
johnc@1829 1495
ysr@777 1496 for (int i = 0; i < _aux_num; ++i) {
ysr@777 1497 if (_cur_aux_times_set[i]) {
ysr@777 1498 char buffer[96];
ysr@777 1499 sprintf(buffer, "Aux%d", i);
ysr@777 1500 print_stats(1, buffer, _cur_aux_times_ms[i]);
ysr@777 1501 }
ysr@777 1502 }
ysr@777 1503 }
ysr@777 1504
ysr@777 1505 // Update the efficiency-since-mark vars.
ysr@777 1506 double proc_ms = elapsed_ms * (double) _parallel_gc_threads;
ysr@777 1507 if (elapsed_ms < MIN_TIMER_GRANULARITY) {
ysr@777 1508 // This usually happens due to the timer not having the required
ysr@777 1509 // granularity. Some Linuxes are the usual culprits.
ysr@777 1510 // We'll just set it to something (arbitrarily) small.
ysr@777 1511 proc_ms = 1.0;
ysr@777 1512 }
ysr@777 1513 double cur_efficiency = (double) freed_bytes / proc_ms;
ysr@777 1514
ysr@777 1515 bool new_in_marking_window = _in_marking_window;
ysr@777 1516 bool new_in_marking_window_im = false;
tonyp@1794 1517 if (during_initial_mark_pause()) {
ysr@777 1518 new_in_marking_window = true;
ysr@777 1519 new_in_marking_window_im = true;
ysr@777 1520 }
ysr@777 1521
brutisso@3065 1522 if (_last_full_young_gc) {
johnc@3178 1523 if (!last_pause_included_initial_mark) {
johnc@3178 1524 ergo_verbose2(ErgoPartiallyYoungGCs,
johnc@3178 1525 "start partially-young GCs",
johnc@3178 1526 ergo_format_byte_perc("known garbage"),
johnc@3178 1527 _known_garbage_bytes, _known_garbage_ratio * 100.0);
johnc@3178 1528 set_full_young_gcs(false);
johnc@3178 1529 } else {
johnc@3178 1530 ergo_verbose0(ErgoPartiallyYoungGCs,
johnc@3178 1531 "do not start partially-young GCs",
johnc@3178 1532 ergo_format_reason("concurrent cycle is about to start"));
johnc@3178 1533 }
brutisso@3065 1534 _last_full_young_gc = false;
brutisso@3065 1535 }
brutisso@3065 1536
brutisso@3065 1537 if ( !_last_young_gc_full ) {
tonyp@3114 1538 if (_should_revert_to_full_young_gcs) {
tonyp@3114 1539 ergo_verbose2(ErgoPartiallyYoungGCs,
tonyp@3114 1540 "end partially-young GCs",
tonyp@3114 1541 ergo_format_reason("partially-young GCs end requested")
tonyp@3114 1542 ergo_format_byte_perc("known garbage"),
tonyp@3114 1543 _known_garbage_bytes, _known_garbage_ratio * 100.0);
tonyp@3114 1544 set_full_young_gcs(true);
tonyp@3114 1545 } else if (_known_garbage_ratio < 0.05) {
tonyp@3114 1546 ergo_verbose3(ErgoPartiallyYoungGCs,
tonyp@3114 1547 "end partially-young GCs",
tonyp@3114 1548 ergo_format_reason("known garbage percent lower than threshold")
tonyp@3114 1549 ergo_format_byte_perc("known garbage")
tonyp@3114 1550 ergo_format_perc("threshold"),
tonyp@3114 1551 _known_garbage_bytes, _known_garbage_ratio * 100.0,
tonyp@3114 1552 0.05 * 100.0);
tonyp@3114 1553 set_full_young_gcs(true);
tonyp@3114 1554 } else if (adaptive_young_list_length() &&
tonyp@3114 1555 (get_gc_eff_factor() * cur_efficiency < predict_young_gc_eff())) {
tonyp@3114 1556 ergo_verbose5(ErgoPartiallyYoungGCs,
tonyp@3114 1557 "end partially-young GCs",
tonyp@3114 1558 ergo_format_reason("current GC efficiency lower than "
tonyp@3114 1559 "predicted fully-young GC efficiency")
tonyp@3114 1560 ergo_format_double("GC efficiency factor")
tonyp@3114 1561 ergo_format_double("current GC efficiency")
tonyp@3114 1562 ergo_format_double("predicted fully-young GC efficiency")
tonyp@3114 1563 ergo_format_byte_perc("known garbage"),
tonyp@3114 1564 get_gc_eff_factor(), cur_efficiency,
tonyp@3114 1565 predict_young_gc_eff(),
tonyp@3114 1566 _known_garbage_bytes, _known_garbage_ratio * 100.0);
tonyp@3114 1567 set_full_young_gcs(true);
ysr@777 1568 }
brutisso@3065 1569 }
brutisso@3065 1570 _should_revert_to_full_young_gcs = false;
brutisso@3065 1571
brutisso@3065 1572 if (_last_young_gc_full && !_during_marking) {
brutisso@3065 1573 _young_gc_eff_seq->add(cur_efficiency);
ysr@777 1574 }
ysr@777 1575
ysr@777 1576 _short_lived_surv_rate_group->start_adding_regions();
ysr@777 1577 // do that for any other surv rate groupsx
ysr@777 1578
ysr@777 1579 // <NEW PREDICTION>
ysr@777 1580
apetrusenko@1112 1581 if (update_stats) {
ysr@777 1582 double pause_time_ms = elapsed_ms;
ysr@777 1583
ysr@777 1584 size_t diff = 0;
ysr@777 1585 if (_max_pending_cards >= _pending_cards)
ysr@777 1586 diff = _max_pending_cards - _pending_cards;
ysr@777 1587 _pending_card_diff_seq->add((double) diff);
ysr@777 1588
ysr@777 1589 double cost_per_card_ms = 0.0;
ysr@777 1590 if (_pending_cards > 0) {
ysr@777 1591 cost_per_card_ms = update_rs_time / (double) _pending_cards;
ysr@777 1592 _cost_per_card_ms_seq->add(cost_per_card_ms);
ysr@777 1593 }
ysr@777 1594
ysr@777 1595 size_t cards_scanned = _g1->cards_scanned();
ysr@777 1596
ysr@777 1597 double cost_per_entry_ms = 0.0;
ysr@777 1598 if (cards_scanned > 10) {
ysr@777 1599 cost_per_entry_ms = scan_rs_time / (double) cards_scanned;
ysr@777 1600 if (_last_young_gc_full)
ysr@777 1601 _cost_per_entry_ms_seq->add(cost_per_entry_ms);
ysr@777 1602 else
ysr@777 1603 _partially_young_cost_per_entry_ms_seq->add(cost_per_entry_ms);
ysr@777 1604 }
ysr@777 1605
ysr@777 1606 if (_max_rs_lengths > 0) {
ysr@777 1607 double cards_per_entry_ratio =
ysr@777 1608 (double) cards_scanned / (double) _max_rs_lengths;
ysr@777 1609 if (_last_young_gc_full)
ysr@777 1610 _fully_young_cards_per_entry_ratio_seq->add(cards_per_entry_ratio);
ysr@777 1611 else
ysr@777 1612 _partially_young_cards_per_entry_ratio_seq->add(cards_per_entry_ratio);
ysr@777 1613 }
ysr@777 1614
ysr@777 1615 size_t rs_length_diff = _max_rs_lengths - _recorded_rs_lengths;
ysr@777 1616 if (rs_length_diff >= 0)
ysr@777 1617 _rs_length_diff_seq->add((double) rs_length_diff);
ysr@777 1618
ysr@777 1619 size_t copied_bytes = surviving_bytes;
ysr@777 1620 double cost_per_byte_ms = 0.0;
ysr@777 1621 if (copied_bytes > 0) {
ysr@777 1622 cost_per_byte_ms = obj_copy_time / (double) copied_bytes;
ysr@777 1623 if (_in_marking_window)
ysr@777 1624 _cost_per_byte_ms_during_cm_seq->add(cost_per_byte_ms);
ysr@777 1625 else
ysr@777 1626 _cost_per_byte_ms_seq->add(cost_per_byte_ms);
ysr@777 1627 }
ysr@777 1628
ysr@777 1629 double all_other_time_ms = pause_time_ms -
johnc@1829 1630 (update_rs_time + scan_rs_time + obj_copy_time +
ysr@777 1631 _mark_closure_time_ms + termination_time);
ysr@777 1632
ysr@777 1633 double young_other_time_ms = 0.0;
ysr@777 1634 if (_recorded_young_regions > 0) {
ysr@777 1635 young_other_time_ms =
ysr@777 1636 _recorded_young_cset_choice_time_ms +
ysr@777 1637 _recorded_young_free_cset_time_ms;
ysr@777 1638 _young_other_cost_per_region_ms_seq->add(young_other_time_ms /
ysr@777 1639 (double) _recorded_young_regions);
ysr@777 1640 }
ysr@777 1641 double non_young_other_time_ms = 0.0;
ysr@777 1642 if (_recorded_non_young_regions > 0) {
ysr@777 1643 non_young_other_time_ms =
ysr@777 1644 _recorded_non_young_cset_choice_time_ms +
ysr@777 1645 _recorded_non_young_free_cset_time_ms;
ysr@777 1646
ysr@777 1647 _non_young_other_cost_per_region_ms_seq->add(non_young_other_time_ms /
ysr@777 1648 (double) _recorded_non_young_regions);
ysr@777 1649 }
ysr@777 1650
ysr@777 1651 double constant_other_time_ms = all_other_time_ms -
ysr@777 1652 (young_other_time_ms + non_young_other_time_ms);
ysr@777 1653 _constant_other_time_ms_seq->add(constant_other_time_ms);
ysr@777 1654
ysr@777 1655 double survival_ratio = 0.0;
ysr@777 1656 if (_bytes_in_collection_set_before_gc > 0) {
tonyp@3028 1657 survival_ratio = (double) _bytes_copied_during_gc /
tonyp@3028 1658 (double) _bytes_in_collection_set_before_gc;
ysr@777 1659 }
ysr@777 1660
ysr@777 1661 _pending_cards_seq->add((double) _pending_cards);
ysr@777 1662 _scanned_cards_seq->add((double) cards_scanned);
ysr@777 1663 _rs_lengths_seq->add((double) _max_rs_lengths);
ysr@777 1664
ysr@777 1665 double expensive_region_limit_ms =
johnc@1186 1666 (double) MaxGCPauseMillis - predict_constant_other_time_ms();
ysr@777 1667 if (expensive_region_limit_ms < 0.0) {
ysr@777 1668 // this means that the other time was predicted to be longer than
ysr@777 1669 // than the max pause time
johnc@1186 1670 expensive_region_limit_ms = (double) MaxGCPauseMillis;
ysr@777 1671 }
ysr@777 1672 _expensive_region_limit_ms = expensive_region_limit_ms;
ysr@777 1673
ysr@777 1674 if (PREDICTIONS_VERBOSE) {
ysr@777 1675 gclog_or_tty->print_cr("");
ysr@777 1676 gclog_or_tty->print_cr("PREDICTIONS %1.4lf %d "
johnc@1829 1677 "REGIONS %d %d %d "
ysr@777 1678 "PENDING_CARDS %d %d "
ysr@777 1679 "CARDS_SCANNED %d %d "
ysr@777 1680 "RS_LENGTHS %d %d "
ysr@777 1681 "RS_UPDATE %1.6lf %1.6lf RS_SCAN %1.6lf %1.6lf "
ysr@777 1682 "SURVIVAL_RATIO %1.6lf %1.6lf "
ysr@777 1683 "OBJECT_COPY %1.6lf %1.6lf OTHER_CONSTANT %1.6lf %1.6lf "
ysr@777 1684 "OTHER_YOUNG %1.6lf %1.6lf "
ysr@777 1685 "OTHER_NON_YOUNG %1.6lf %1.6lf "
ysr@777 1686 "VTIME_DIFF %1.6lf TERMINATION %1.6lf "
ysr@777 1687 "ELAPSED %1.6lf %1.6lf ",
ysr@777 1688 _cur_collection_start_sec,
ysr@777 1689 (!_last_young_gc_full) ? 2 :
ysr@777 1690 (last_pause_included_initial_mark) ? 1 : 0,
ysr@777 1691 _recorded_region_num,
ysr@777 1692 _recorded_young_regions,
ysr@777 1693 _recorded_non_young_regions,
ysr@777 1694 _predicted_pending_cards, _pending_cards,
ysr@777 1695 _predicted_cards_scanned, cards_scanned,
ysr@777 1696 _predicted_rs_lengths, _max_rs_lengths,
ysr@777 1697 _predicted_rs_update_time_ms, update_rs_time,
ysr@777 1698 _predicted_rs_scan_time_ms, scan_rs_time,
ysr@777 1699 _predicted_survival_ratio, survival_ratio,
ysr@777 1700 _predicted_object_copy_time_ms, obj_copy_time,
ysr@777 1701 _predicted_constant_other_time_ms, constant_other_time_ms,
ysr@777 1702 _predicted_young_other_time_ms, young_other_time_ms,
ysr@777 1703 _predicted_non_young_other_time_ms,
ysr@777 1704 non_young_other_time_ms,
ysr@777 1705 _vtime_diff_ms, termination_time,
ysr@777 1706 _predicted_pause_time_ms, elapsed_ms);
ysr@777 1707 }
ysr@777 1708
ysr@777 1709 if (G1PolicyVerbose > 0) {
ysr@777 1710 gclog_or_tty->print_cr("Pause Time, predicted: %1.4lfms (predicted %s), actual: %1.4lfms",
ysr@777 1711 _predicted_pause_time_ms,
ysr@777 1712 (_within_target) ? "within" : "outside",
ysr@777 1713 elapsed_ms);
ysr@777 1714 }
ysr@777 1715
ysr@777 1716 }
ysr@777 1717
ysr@777 1718 _in_marking_window = new_in_marking_window;
ysr@777 1719 _in_marking_window_im = new_in_marking_window_im;
ysr@777 1720 _free_regions_at_end_of_collection = _g1->free_regions();
tonyp@3119 1721 update_young_list_target_length();
ysr@777 1722
iveresov@1546 1723 // Note that _mmu_tracker->max_gc_time() returns the time in seconds.
tonyp@1717 1724 double update_rs_time_goal_ms = _mmu_tracker->max_gc_time() * MILLIUNITS * G1RSetUpdatingPauseTimePercent / 100.0;
iveresov@1546 1725 adjust_concurrent_refinement(update_rs_time, update_rs_processed_buffers, update_rs_time_goal_ms);
ysr@777 1726 // </NEW PREDICTION>
tonyp@3209 1727
tonyp@3209 1728 assert(assertMarkedBytesDataOK(), "Marked regions not OK at pause end.");
ysr@777 1729 }
ysr@777 1730
tonyp@2961 1731 #define EXT_SIZE_FORMAT "%d%s"
tonyp@2961 1732 #define EXT_SIZE_PARAMS(bytes) \
tonyp@2961 1733 byte_size_in_proper_unit((bytes)), \
tonyp@2961 1734 proper_unit_for_byte_size((bytes))
tonyp@2961 1735
tonyp@2961 1736 void G1CollectorPolicy::print_heap_transition() {
tonyp@2961 1737 if (PrintGCDetails) {
tonyp@2961 1738 YoungList* young_list = _g1->young_list();
tonyp@2961 1739 size_t eden_bytes = young_list->eden_used_bytes();
tonyp@2961 1740 size_t survivor_bytes = young_list->survivor_used_bytes();
tonyp@2961 1741 size_t used_before_gc = _cur_collection_pause_used_at_start_bytes;
tonyp@2961 1742 size_t used = _g1->used();
tonyp@2961 1743 size_t capacity = _g1->capacity();
brutisso@3120 1744 size_t eden_capacity =
brutisso@3120 1745 (_young_list_target_length * HeapRegion::GrainBytes) - survivor_bytes;
tonyp@2961 1746
tonyp@2961 1747 gclog_or_tty->print_cr(
brutisso@3120 1748 " [Eden: "EXT_SIZE_FORMAT"("EXT_SIZE_FORMAT")->"EXT_SIZE_FORMAT"("EXT_SIZE_FORMAT") "
brutisso@3120 1749 "Survivors: "EXT_SIZE_FORMAT"->"EXT_SIZE_FORMAT" "
brutisso@3120 1750 "Heap: "EXT_SIZE_FORMAT"("EXT_SIZE_FORMAT")->"
brutisso@3120 1751 EXT_SIZE_FORMAT"("EXT_SIZE_FORMAT")]",
brutisso@3120 1752 EXT_SIZE_PARAMS(_eden_bytes_before_gc),
brutisso@3120 1753 EXT_SIZE_PARAMS(_prev_eden_capacity),
brutisso@3120 1754 EXT_SIZE_PARAMS(eden_bytes),
brutisso@3120 1755 EXT_SIZE_PARAMS(eden_capacity),
brutisso@3120 1756 EXT_SIZE_PARAMS(_survivor_bytes_before_gc),
brutisso@3120 1757 EXT_SIZE_PARAMS(survivor_bytes),
brutisso@3120 1758 EXT_SIZE_PARAMS(used_before_gc),
brutisso@3120 1759 EXT_SIZE_PARAMS(_capacity_before_gc),
brutisso@3120 1760 EXT_SIZE_PARAMS(used),
brutisso@3120 1761 EXT_SIZE_PARAMS(capacity));
brutisso@3120 1762
brutisso@3120 1763 _prev_eden_capacity = eden_capacity;
tonyp@2961 1764 } else if (PrintGC) {
tonyp@2961 1765 _g1->print_size_transition(gclog_or_tty,
tonyp@2961 1766 _cur_collection_pause_used_at_start_bytes,
tonyp@2961 1767 _g1->used(), _g1->capacity());
tonyp@2961 1768 }
tonyp@2961 1769 }
tonyp@2961 1770
ysr@777 1771 // <NEW PREDICTION>
ysr@777 1772
iveresov@1546 1773 void G1CollectorPolicy::adjust_concurrent_refinement(double update_rs_time,
iveresov@1546 1774 double update_rs_processed_buffers,
iveresov@1546 1775 double goal_ms) {
iveresov@1546 1776 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set();
iveresov@1546 1777 ConcurrentG1Refine *cg1r = G1CollectedHeap::heap()->concurrent_g1_refine();
iveresov@1546 1778
tonyp@1717 1779 if (G1UseAdaptiveConcRefinement) {
iveresov@1546 1780 const int k_gy = 3, k_gr = 6;
iveresov@1546 1781 const double inc_k = 1.1, dec_k = 0.9;
iveresov@1546 1782
iveresov@1546 1783 int g = cg1r->green_zone();
iveresov@1546 1784 if (update_rs_time > goal_ms) {
iveresov@1546 1785 g = (int)(g * dec_k); // Can become 0, that's OK. That would mean a mutator-only processing.
iveresov@1546 1786 } else {
iveresov@1546 1787 if (update_rs_time < goal_ms && update_rs_processed_buffers > g) {
iveresov@1546 1788 g = (int)MAX2(g * inc_k, g + 1.0);
iveresov@1546 1789 }
iveresov@1546 1790 }
iveresov@1546 1791 // Change the refinement threads params
iveresov@1546 1792 cg1r->set_green_zone(g);
iveresov@1546 1793 cg1r->set_yellow_zone(g * k_gy);
iveresov@1546 1794 cg1r->set_red_zone(g * k_gr);
iveresov@1546 1795 cg1r->reinitialize_threads();
iveresov@1546 1796
iveresov@1546 1797 int processing_threshold_delta = MAX2((int)(cg1r->green_zone() * sigma()), 1);
iveresov@1546 1798 int processing_threshold = MIN2(cg1r->green_zone() + processing_threshold_delta,
iveresov@1546 1799 cg1r->yellow_zone());
iveresov@1546 1800 // Change the barrier params
iveresov@1546 1801 dcqs.set_process_completed_threshold(processing_threshold);
iveresov@1546 1802 dcqs.set_max_completed_queue(cg1r->red_zone());
iveresov@1546 1803 }
iveresov@1546 1804
iveresov@1546 1805 int curr_queue_size = dcqs.completed_buffers_num();
iveresov@1546 1806 if (curr_queue_size >= cg1r->yellow_zone()) {
iveresov@1546 1807 dcqs.set_completed_queue_padding(curr_queue_size);
iveresov@1546 1808 } else {
iveresov@1546 1809 dcqs.set_completed_queue_padding(0);
iveresov@1546 1810 }
iveresov@1546 1811 dcqs.notify_if_necessary();
iveresov@1546 1812 }
iveresov@1546 1813
ysr@777 1814 double
ysr@777 1815 G1CollectorPolicy::
ysr@777 1816 predict_young_collection_elapsed_time_ms(size_t adjustment) {
ysr@777 1817 guarantee( adjustment == 0 || adjustment == 1, "invariant" );
ysr@777 1818
ysr@777 1819 G1CollectedHeap* g1h = G1CollectedHeap::heap();
johnc@1829 1820 size_t young_num = g1h->young_list()->length();
ysr@777 1821 if (young_num == 0)
ysr@777 1822 return 0.0;
ysr@777 1823
ysr@777 1824 young_num += adjustment;
ysr@777 1825 size_t pending_cards = predict_pending_cards();
johnc@1829 1826 size_t rs_lengths = g1h->young_list()->sampled_rs_lengths() +
ysr@777 1827 predict_rs_length_diff();
ysr@777 1828 size_t card_num;
ysr@777 1829 if (full_young_gcs())
ysr@777 1830 card_num = predict_young_card_num(rs_lengths);
ysr@777 1831 else
ysr@777 1832 card_num = predict_non_young_card_num(rs_lengths);
ysr@777 1833 size_t young_byte_size = young_num * HeapRegion::GrainBytes;
ysr@777 1834 double accum_yg_surv_rate =
ysr@777 1835 _short_lived_surv_rate_group->accum_surv_rate(adjustment);
ysr@777 1836
ysr@777 1837 size_t bytes_to_copy =
ysr@777 1838 (size_t) (accum_yg_surv_rate * (double) HeapRegion::GrainBytes);
ysr@777 1839
ysr@777 1840 return
ysr@777 1841 predict_rs_update_time_ms(pending_cards) +
ysr@777 1842 predict_rs_scan_time_ms(card_num) +
ysr@777 1843 predict_object_copy_time_ms(bytes_to_copy) +
ysr@777 1844 predict_young_other_time_ms(young_num) +
ysr@777 1845 predict_constant_other_time_ms();
ysr@777 1846 }
ysr@777 1847
ysr@777 1848 double
ysr@777 1849 G1CollectorPolicy::predict_base_elapsed_time_ms(size_t pending_cards) {
ysr@777 1850 size_t rs_length = predict_rs_length_diff();
ysr@777 1851 size_t card_num;
ysr@777 1852 if (full_young_gcs())
ysr@777 1853 card_num = predict_young_card_num(rs_length);
ysr@777 1854 else
ysr@777 1855 card_num = predict_non_young_card_num(rs_length);
ysr@777 1856 return predict_base_elapsed_time_ms(pending_cards, card_num);
ysr@777 1857 }
ysr@777 1858
ysr@777 1859 double
ysr@777 1860 G1CollectorPolicy::predict_base_elapsed_time_ms(size_t pending_cards,
ysr@777 1861 size_t scanned_cards) {
ysr@777 1862 return
ysr@777 1863 predict_rs_update_time_ms(pending_cards) +
ysr@777 1864 predict_rs_scan_time_ms(scanned_cards) +
ysr@777 1865 predict_constant_other_time_ms();
ysr@777 1866 }
ysr@777 1867
ysr@777 1868 double
ysr@777 1869 G1CollectorPolicy::predict_region_elapsed_time_ms(HeapRegion* hr,
ysr@777 1870 bool young) {
ysr@777 1871 size_t rs_length = hr->rem_set()->occupied();
ysr@777 1872 size_t card_num;
ysr@777 1873 if (full_young_gcs())
ysr@777 1874 card_num = predict_young_card_num(rs_length);
ysr@777 1875 else
ysr@777 1876 card_num = predict_non_young_card_num(rs_length);
ysr@777 1877 size_t bytes_to_copy = predict_bytes_to_copy(hr);
ysr@777 1878
ysr@777 1879 double region_elapsed_time_ms =
ysr@777 1880 predict_rs_scan_time_ms(card_num) +
ysr@777 1881 predict_object_copy_time_ms(bytes_to_copy);
ysr@777 1882
ysr@777 1883 if (young)
ysr@777 1884 region_elapsed_time_ms += predict_young_other_time_ms(1);
ysr@777 1885 else
ysr@777 1886 region_elapsed_time_ms += predict_non_young_other_time_ms(1);
ysr@777 1887
ysr@777 1888 return region_elapsed_time_ms;
ysr@777 1889 }
ysr@777 1890
ysr@777 1891 size_t
ysr@777 1892 G1CollectorPolicy::predict_bytes_to_copy(HeapRegion* hr) {
ysr@777 1893 size_t bytes_to_copy;
ysr@777 1894 if (hr->is_marked())
ysr@777 1895 bytes_to_copy = hr->max_live_bytes();
ysr@777 1896 else {
ysr@777 1897 guarantee( hr->is_young() && hr->age_in_surv_rate_group() != -1,
ysr@777 1898 "invariant" );
ysr@777 1899 int age = hr->age_in_surv_rate_group();
apetrusenko@980 1900 double yg_surv_rate = predict_yg_surv_rate(age, hr->surv_rate_group());
ysr@777 1901 bytes_to_copy = (size_t) ((double) hr->used() * yg_surv_rate);
ysr@777 1902 }
ysr@777 1903
ysr@777 1904 return bytes_to_copy;
ysr@777 1905 }
ysr@777 1906
ysr@777 1907 void
ysr@777 1908 G1CollectorPolicy::start_recording_regions() {
ysr@777 1909 _recorded_rs_lengths = 0;
ysr@777 1910 _recorded_young_regions = 0;
ysr@777 1911 _recorded_non_young_regions = 0;
ysr@777 1912
ysr@777 1913 #if PREDICTIONS_VERBOSE
ysr@777 1914 _recorded_marked_bytes = 0;
ysr@777 1915 _recorded_young_bytes = 0;
ysr@777 1916 _predicted_bytes_to_copy = 0;
johnc@1829 1917 _predicted_rs_lengths = 0;
johnc@1829 1918 _predicted_cards_scanned = 0;
ysr@777 1919 #endif // PREDICTIONS_VERBOSE
ysr@777 1920 }
ysr@777 1921
ysr@777 1922 void
johnc@1829 1923 G1CollectorPolicy::record_cset_region_info(HeapRegion* hr, bool young) {
ysr@777 1924 #if PREDICTIONS_VERBOSE
johnc@1829 1925 if (!young) {
ysr@777 1926 _recorded_marked_bytes += hr->max_live_bytes();
ysr@777 1927 }
ysr@777 1928 _predicted_bytes_to_copy += predict_bytes_to_copy(hr);
ysr@777 1929 #endif // PREDICTIONS_VERBOSE
ysr@777 1930
ysr@777 1931 size_t rs_length = hr->rem_set()->occupied();
ysr@777 1932 _recorded_rs_lengths += rs_length;
ysr@777 1933 }
ysr@777 1934
ysr@777 1935 void
johnc@1829 1936 G1CollectorPolicy::record_non_young_cset_region(HeapRegion* hr) {
johnc@1829 1937 assert(!hr->is_young(), "should not call this");
johnc@1829 1938 ++_recorded_non_young_regions;
johnc@1829 1939 record_cset_region_info(hr, false);
johnc@1829 1940 }
johnc@1829 1941
johnc@1829 1942 void
johnc@1829 1943 G1CollectorPolicy::set_recorded_young_regions(size_t n_regions) {
johnc@1829 1944 _recorded_young_regions = n_regions;
johnc@1829 1945 }
johnc@1829 1946
johnc@1829 1947 void G1CollectorPolicy::set_recorded_young_bytes(size_t bytes) {
johnc@1829 1948 #if PREDICTIONS_VERBOSE
johnc@1829 1949 _recorded_young_bytes = bytes;
johnc@1829 1950 #endif // PREDICTIONS_VERBOSE
johnc@1829 1951 }
johnc@1829 1952
johnc@1829 1953 void G1CollectorPolicy::set_recorded_rs_lengths(size_t rs_lengths) {
johnc@1829 1954 _recorded_rs_lengths = rs_lengths;
johnc@1829 1955 }
johnc@1829 1956
johnc@1829 1957 void G1CollectorPolicy::set_predicted_bytes_to_copy(size_t bytes) {
johnc@1829 1958 _predicted_bytes_to_copy = bytes;
ysr@777 1959 }
ysr@777 1960
ysr@777 1961 void
ysr@777 1962 G1CollectorPolicy::end_recording_regions() {
johnc@1829 1963 // The _predicted_pause_time_ms field is referenced in code
johnc@1829 1964 // not under PREDICTIONS_VERBOSE. Let's initialize it.
johnc@1829 1965 _predicted_pause_time_ms = -1.0;
johnc@1829 1966
ysr@777 1967 #if PREDICTIONS_VERBOSE
ysr@777 1968 _predicted_pending_cards = predict_pending_cards();
ysr@777 1969 _predicted_rs_lengths = _recorded_rs_lengths + predict_rs_length_diff();
ysr@777 1970 if (full_young_gcs())
ysr@777 1971 _predicted_cards_scanned += predict_young_card_num(_predicted_rs_lengths);
ysr@777 1972 else
ysr@777 1973 _predicted_cards_scanned +=
ysr@777 1974 predict_non_young_card_num(_predicted_rs_lengths);
ysr@777 1975 _recorded_region_num = _recorded_young_regions + _recorded_non_young_regions;
ysr@777 1976
ysr@777 1977 _predicted_rs_update_time_ms =
ysr@777 1978 predict_rs_update_time_ms(_g1->pending_card_num());
ysr@777 1979 _predicted_rs_scan_time_ms =
ysr@777 1980 predict_rs_scan_time_ms(_predicted_cards_scanned);
ysr@777 1981 _predicted_object_copy_time_ms =
ysr@777 1982 predict_object_copy_time_ms(_predicted_bytes_to_copy);
ysr@777 1983 _predicted_constant_other_time_ms =
ysr@777 1984 predict_constant_other_time_ms();
ysr@777 1985 _predicted_young_other_time_ms =
ysr@777 1986 predict_young_other_time_ms(_recorded_young_regions);
ysr@777 1987 _predicted_non_young_other_time_ms =
ysr@777 1988 predict_non_young_other_time_ms(_recorded_non_young_regions);
ysr@777 1989
ysr@777 1990 _predicted_pause_time_ms =
ysr@777 1991 _predicted_rs_update_time_ms +
ysr@777 1992 _predicted_rs_scan_time_ms +
ysr@777 1993 _predicted_object_copy_time_ms +
ysr@777 1994 _predicted_constant_other_time_ms +
ysr@777 1995 _predicted_young_other_time_ms +
ysr@777 1996 _predicted_non_young_other_time_ms;
ysr@777 1997 #endif // PREDICTIONS_VERBOSE
ysr@777 1998 }
ysr@777 1999
ysr@777 2000 void G1CollectorPolicy::check_if_region_is_too_expensive(double
ysr@777 2001 predicted_time_ms) {
ysr@777 2002 // I don't think we need to do this when in young GC mode since
ysr@777 2003 // marking will be initiated next time we hit the soft limit anyway...
ysr@777 2004 if (predicted_time_ms > _expensive_region_limit_ms) {
tonyp@3114 2005 ergo_verbose2(ErgoPartiallyYoungGCs,
tonyp@3114 2006 "request partially-young GCs end",
tonyp@3114 2007 ergo_format_reason("predicted region time higher than threshold")
tonyp@3114 2008 ergo_format_ms("predicted region time")
tonyp@3114 2009 ergo_format_ms("threshold"),
tonyp@3114 2010 predicted_time_ms, _expensive_region_limit_ms);
brutisso@3065 2011 // no point in doing another partial one
brutisso@3065 2012 _should_revert_to_full_young_gcs = true;
ysr@777 2013 }
ysr@777 2014 }
ysr@777 2015
ysr@777 2016 // </NEW PREDICTION>
ysr@777 2017
ysr@777 2018
ysr@777 2019 void G1CollectorPolicy::update_recent_gc_times(double end_time_sec,
ysr@777 2020 double elapsed_ms) {
ysr@777 2021 _recent_gc_times_ms->add(elapsed_ms);
ysr@777 2022 _recent_prev_end_times_for_all_gcs_sec->add(end_time_sec);
ysr@777 2023 _prev_collection_pause_end_ms = end_time_sec * 1000.0;
ysr@777 2024 }
ysr@777 2025
ysr@777 2026 double G1CollectorPolicy::recent_avg_time_for_pauses_ms() {
johnc@3021 2027 if (_recent_pause_times_ms->num() == 0) {
johnc@3021 2028 return (double) MaxGCPauseMillis;
johnc@3021 2029 }
johnc@3021 2030 return _recent_pause_times_ms->avg();
ysr@777 2031 }
ysr@777 2032
johnc@3021 2033 double G1CollectorPolicy::recent_avg_time_for_rs_scan_ms() {
johnc@3021 2034 if (_recent_rs_scan_times_ms->num() == 0) {
johnc@1186 2035 return (double)MaxGCPauseMillis/3.0;
johnc@3021 2036 }
johnc@3021 2037 return _recent_rs_scan_times_ms->avg();
ysr@777 2038 }
ysr@777 2039
ysr@777 2040 int G1CollectorPolicy::number_of_recent_gcs() {
johnc@3021 2041 assert(_recent_rs_scan_times_ms->num() ==
ysr@777 2042 _recent_pause_times_ms->num(), "Sequence out of sync");
ysr@777 2043 assert(_recent_pause_times_ms->num() ==
ysr@777 2044 _recent_CS_bytes_used_before->num(), "Sequence out of sync");
ysr@777 2045 assert(_recent_CS_bytes_used_before->num() ==
ysr@777 2046 _recent_CS_bytes_surviving->num(), "Sequence out of sync");
johnc@3021 2047
ysr@777 2048 return _recent_pause_times_ms->num();
ysr@777 2049 }
ysr@777 2050
ysr@777 2051 double G1CollectorPolicy::recent_avg_survival_fraction() {
ysr@777 2052 return recent_avg_survival_fraction_work(_recent_CS_bytes_surviving,
ysr@777 2053 _recent_CS_bytes_used_before);
ysr@777 2054 }
ysr@777 2055
ysr@777 2056 double G1CollectorPolicy::last_survival_fraction() {
ysr@777 2057 return last_survival_fraction_work(_recent_CS_bytes_surviving,
ysr@777 2058 _recent_CS_bytes_used_before);
ysr@777 2059 }
ysr@777 2060
ysr@777 2061 double
ysr@777 2062 G1CollectorPolicy::recent_avg_survival_fraction_work(TruncatedSeq* surviving,
ysr@777 2063 TruncatedSeq* before) {
ysr@777 2064 assert(surviving->num() == before->num(), "Sequence out of sync");
ysr@777 2065 if (before->sum() > 0.0) {
ysr@777 2066 double recent_survival_rate = surviving->sum() / before->sum();
ysr@777 2067 // We exempt parallel collection from this check because Alloc Buffer
ysr@777 2068 // fragmentation can produce negative collections.
ysr@777 2069 // Further, we're now always doing parallel collection. But I'm still
ysr@777 2070 // leaving this here as a placeholder for a more precise assertion later.
ysr@777 2071 // (DLD, 10/05.)
jmasa@2188 2072 assert((true || G1CollectedHeap::use_parallel_gc_threads()) ||
ysr@777 2073 _g1->evacuation_failed() ||
ysr@777 2074 recent_survival_rate <= 1.0, "Or bad frac");
ysr@777 2075 return recent_survival_rate;
ysr@777 2076 } else {
ysr@777 2077 return 1.0; // Be conservative.
ysr@777 2078 }
ysr@777 2079 }
ysr@777 2080
ysr@777 2081 double
ysr@777 2082 G1CollectorPolicy::last_survival_fraction_work(TruncatedSeq* surviving,
ysr@777 2083 TruncatedSeq* before) {
ysr@777 2084 assert(surviving->num() == before->num(), "Sequence out of sync");
ysr@777 2085 if (surviving->num() > 0 && before->last() > 0.0) {
ysr@777 2086 double last_survival_rate = surviving->last() / before->last();
ysr@777 2087 // We exempt parallel collection from this check because Alloc Buffer
ysr@777 2088 // fragmentation can produce negative collections.
ysr@777 2089 // Further, we're now always doing parallel collection. But I'm still
ysr@777 2090 // leaving this here as a placeholder for a more precise assertion later.
ysr@777 2091 // (DLD, 10/05.)
jmasa@2188 2092 assert((true || G1CollectedHeap::use_parallel_gc_threads()) ||
ysr@777 2093 last_survival_rate <= 1.0, "Or bad frac");
ysr@777 2094 return last_survival_rate;
ysr@777 2095 } else {
ysr@777 2096 return 1.0;
ysr@777 2097 }
ysr@777 2098 }
ysr@777 2099
ysr@777 2100 static const int survival_min_obs = 5;
ysr@777 2101 static double survival_min_obs_limits[] = { 0.9, 0.7, 0.5, 0.3, 0.1 };
ysr@777 2102 static const double min_survival_rate = 0.1;
ysr@777 2103
ysr@777 2104 double
ysr@777 2105 G1CollectorPolicy::conservative_avg_survival_fraction_work(double avg,
ysr@777 2106 double latest) {
ysr@777 2107 double res = avg;
ysr@777 2108 if (number_of_recent_gcs() < survival_min_obs) {
ysr@777 2109 res = MAX2(res, survival_min_obs_limits[number_of_recent_gcs()]);
ysr@777 2110 }
ysr@777 2111 res = MAX2(res, latest);
ysr@777 2112 res = MAX2(res, min_survival_rate);
ysr@777 2113 // In the parallel case, LAB fragmentation can produce "negative
ysr@777 2114 // collections"; so can evac failure. Cap at 1.0
ysr@777 2115 res = MIN2(res, 1.0);
ysr@777 2116 return res;
ysr@777 2117 }
ysr@777 2118
ysr@777 2119 size_t G1CollectorPolicy::expansion_amount() {
tonyp@3114 2120 double recent_gc_overhead = recent_avg_pause_time_ratio() * 100.0;
tonyp@3114 2121 double threshold = _gc_overhead_perc;
tonyp@3114 2122 if (recent_gc_overhead > threshold) {
johnc@1186 2123 // We will double the existing space, or take
johnc@1186 2124 // G1ExpandByPercentOfAvailable % of the available expansion
johnc@1186 2125 // space, whichever is smaller, bounded below by a minimum
johnc@1186 2126 // expansion (unless that's all that's left.)
ysr@777 2127 const size_t min_expand_bytes = 1*M;
johnc@2504 2128 size_t reserved_bytes = _g1->max_capacity();
ysr@777 2129 size_t committed_bytes = _g1->capacity();
ysr@777 2130 size_t uncommitted_bytes = reserved_bytes - committed_bytes;
ysr@777 2131 size_t expand_bytes;
ysr@777 2132 size_t expand_bytes_via_pct =
johnc@1186 2133 uncommitted_bytes * G1ExpandByPercentOfAvailable / 100;
ysr@777 2134 expand_bytes = MIN2(expand_bytes_via_pct, committed_bytes);
ysr@777 2135 expand_bytes = MAX2(expand_bytes, min_expand_bytes);
ysr@777 2136 expand_bytes = MIN2(expand_bytes, uncommitted_bytes);
tonyp@3114 2137
tonyp@3114 2138 ergo_verbose5(ErgoHeapSizing,
tonyp@3114 2139 "attempt heap expansion",
tonyp@3114 2140 ergo_format_reason("recent GC overhead higher than "
tonyp@3114 2141 "threshold after GC")
tonyp@3114 2142 ergo_format_perc("recent GC overhead")
tonyp@3114 2143 ergo_format_perc("threshold")
tonyp@3114 2144 ergo_format_byte("uncommitted")
tonyp@3114 2145 ergo_format_byte_perc("calculated expansion amount"),
tonyp@3114 2146 recent_gc_overhead, threshold,
tonyp@3114 2147 uncommitted_bytes,
tonyp@3114 2148 expand_bytes_via_pct, (double) G1ExpandByPercentOfAvailable);
tonyp@3114 2149
ysr@777 2150 return expand_bytes;
ysr@777 2151 } else {
ysr@777 2152 return 0;
ysr@777 2153 }
ysr@777 2154 }
ysr@777 2155
ysr@777 2156 class CountCSClosure: public HeapRegionClosure {
ysr@777 2157 G1CollectorPolicy* _g1_policy;
ysr@777 2158 public:
ysr@777 2159 CountCSClosure(G1CollectorPolicy* g1_policy) :
ysr@777 2160 _g1_policy(g1_policy) {}
ysr@777 2161 bool doHeapRegion(HeapRegion* r) {
ysr@777 2162 _g1_policy->_bytes_in_collection_set_before_gc += r->used();
ysr@777 2163 return false;
ysr@777 2164 }
ysr@777 2165 };
ysr@777 2166
ysr@777 2167 void G1CollectorPolicy::count_CS_bytes_used() {
ysr@777 2168 CountCSClosure cs_closure(this);
ysr@777 2169 _g1->collection_set_iterate(&cs_closure);
ysr@777 2170 }
ysr@777 2171
johnc@3219 2172 void G1CollectorPolicy::print_summary(int level,
johnc@3219 2173 const char* str,
johnc@3219 2174 NumberSeq* seq) const {
ysr@777 2175 double sum = seq->sum();
brutisso@2645 2176 LineBuffer(level + 1).append_and_print_cr("%-24s = %8.2lf s (avg = %8.2lf ms)",
ysr@777 2177 str, sum / 1000.0, seq->avg());
ysr@777 2178 }
ysr@777 2179
johnc@3219 2180 void G1CollectorPolicy::print_summary_sd(int level,
johnc@3219 2181 const char* str,
johnc@3219 2182 NumberSeq* seq) const {
ysr@777 2183 print_summary(level, str, seq);
brutisso@2645 2184 LineBuffer(level + 6).append_and_print_cr("(num = %5d, std dev = %8.2lf ms, max = %8.2lf ms)",
ysr@777 2185 seq->num(), seq->sd(), seq->maximum());
ysr@777 2186 }
ysr@777 2187
ysr@777 2188 void G1CollectorPolicy::check_other_times(int level,
ysr@777 2189 NumberSeq* other_times_ms,
ysr@777 2190 NumberSeq* calc_other_times_ms) const {
ysr@777 2191 bool should_print = false;
brutisso@2645 2192 LineBuffer buf(level + 2);
ysr@777 2193
ysr@777 2194 double max_sum = MAX2(fabs(other_times_ms->sum()),
ysr@777 2195 fabs(calc_other_times_ms->sum()));
ysr@777 2196 double min_sum = MIN2(fabs(other_times_ms->sum()),
ysr@777 2197 fabs(calc_other_times_ms->sum()));
ysr@777 2198 double sum_ratio = max_sum / min_sum;
ysr@777 2199 if (sum_ratio > 1.1) {
ysr@777 2200 should_print = true;
brutisso@2645 2201 buf.append_and_print_cr("## CALCULATED OTHER SUM DOESN'T MATCH RECORDED ###");
ysr@777 2202 }
ysr@777 2203
ysr@777 2204 double max_avg = MAX2(fabs(other_times_ms->avg()),
ysr@777 2205 fabs(calc_other_times_ms->avg()));
ysr@777 2206 double min_avg = MIN2(fabs(other_times_ms->avg()),
ysr@777 2207 fabs(calc_other_times_ms->avg()));
ysr@777 2208 double avg_ratio = max_avg / min_avg;
ysr@777 2209 if (avg_ratio > 1.1) {
ysr@777 2210 should_print = true;
brutisso@2645 2211 buf.append_and_print_cr("## CALCULATED OTHER AVG DOESN'T MATCH RECORDED ###");
ysr@777 2212 }
ysr@777 2213
ysr@777 2214 if (other_times_ms->sum() < -0.01) {
brutisso@2645 2215 buf.append_and_print_cr("## RECORDED OTHER SUM IS NEGATIVE ###");
ysr@777 2216 }
ysr@777 2217
ysr@777 2218 if (other_times_ms->avg() < -0.01) {
brutisso@2645 2219 buf.append_and_print_cr("## RECORDED OTHER AVG IS NEGATIVE ###");
ysr@777 2220 }
ysr@777 2221
ysr@777 2222 if (calc_other_times_ms->sum() < -0.01) {
ysr@777 2223 should_print = true;
brutisso@2645 2224 buf.append_and_print_cr("## CALCULATED OTHER SUM IS NEGATIVE ###");
ysr@777 2225 }
ysr@777 2226
ysr@777 2227 if (calc_other_times_ms->avg() < -0.01) {
ysr@777 2228 should_print = true;
brutisso@2645 2229 buf.append_and_print_cr("## CALCULATED OTHER AVG IS NEGATIVE ###");
ysr@777 2230 }
ysr@777 2231
ysr@777 2232 if (should_print)
ysr@777 2233 print_summary(level, "Other(Calc)", calc_other_times_ms);
ysr@777 2234 }
ysr@777 2235
ysr@777 2236 void G1CollectorPolicy::print_summary(PauseSummary* summary) const {
jmasa@2188 2237 bool parallel = G1CollectedHeap::use_parallel_gc_threads();
ysr@777 2238 MainBodySummary* body_summary = summary->main_body_summary();
ysr@777 2239 if (summary->get_total_seq()->num() > 0) {
apetrusenko@1112 2240 print_summary_sd(0, "Evacuation Pauses", summary->get_total_seq());
ysr@777 2241 if (body_summary != NULL) {
ysr@777 2242 print_summary(1, "SATB Drain", body_summary->get_satb_drain_seq());
ysr@777 2243 if (parallel) {
ysr@777 2244 print_summary(1, "Parallel Time", body_summary->get_parallel_seq());
johnc@3219 2245 print_summary(2, "Ext Root Scanning", body_summary->get_ext_root_scan_seq());
johnc@3219 2246 print_summary(2, "Mark Stack Scanning", body_summary->get_mark_stack_scan_seq());
ysr@777 2247 print_summary(2, "Update RS", body_summary->get_update_rs_seq());
ysr@777 2248 print_summary(2, "Scan RS", body_summary->get_scan_rs_seq());
ysr@777 2249 print_summary(2, "Object Copy", body_summary->get_obj_copy_seq());
ysr@777 2250 print_summary(2, "Termination", body_summary->get_termination_seq());
johnc@3219 2251 print_summary(2, "Parallel Other", body_summary->get_parallel_other_seq());
ysr@777 2252 {
ysr@777 2253 NumberSeq* other_parts[] = {
ysr@777 2254 body_summary->get_ext_root_scan_seq(),
ysr@777 2255 body_summary->get_mark_stack_scan_seq(),
johnc@3219 2256 body_summary->get_update_rs_seq(),
ysr@777 2257 body_summary->get_scan_rs_seq(),
ysr@777 2258 body_summary->get_obj_copy_seq(),
ysr@777 2259 body_summary->get_termination_seq()
ysr@777 2260 };
ysr@777 2261 NumberSeq calc_other_times_ms(body_summary->get_parallel_seq(),
johnc@2134 2262 6, other_parts);
ysr@777 2263 check_other_times(2, body_summary->get_parallel_other_seq(),
ysr@777 2264 &calc_other_times_ms);
ysr@777 2265 }
ysr@777 2266 } else {
johnc@3219 2267 print_summary(1, "Ext Root Scanning", body_summary->get_ext_root_scan_seq());
johnc@3219 2268 print_summary(1, "Mark Stack Scanning", body_summary->get_mark_stack_scan_seq());
ysr@777 2269 print_summary(1, "Update RS", body_summary->get_update_rs_seq());
ysr@777 2270 print_summary(1, "Scan RS", body_summary->get_scan_rs_seq());
ysr@777 2271 print_summary(1, "Object Copy", body_summary->get_obj_copy_seq());
ysr@777 2272 }
ysr@777 2273 }
johnc@3219 2274 print_summary(1, "Mark Closure", body_summary->get_mark_closure_seq());
johnc@3219 2275 print_summary(1, "Clear CT", body_summary->get_clear_ct_seq());
ysr@777 2276 print_summary(1, "Other", summary->get_other_seq());
ysr@777 2277 {
johnc@2134 2278 if (body_summary != NULL) {
johnc@2134 2279 NumberSeq calc_other_times_ms;
johnc@2134 2280 if (parallel) {
johnc@2134 2281 // parallel
johnc@2134 2282 NumberSeq* other_parts[] = {
johnc@2134 2283 body_summary->get_satb_drain_seq(),
johnc@2134 2284 body_summary->get_parallel_seq(),
johnc@2134 2285 body_summary->get_clear_ct_seq()
johnc@2134 2286 };
johnc@2134 2287 calc_other_times_ms = NumberSeq(summary->get_total_seq(),
johnc@2134 2288 3, other_parts);
johnc@2134 2289 } else {
johnc@2134 2290 // serial
johnc@2134 2291 NumberSeq* other_parts[] = {
johnc@2134 2292 body_summary->get_satb_drain_seq(),
johnc@2134 2293 body_summary->get_update_rs_seq(),
johnc@2134 2294 body_summary->get_ext_root_scan_seq(),
johnc@2134 2295 body_summary->get_mark_stack_scan_seq(),
johnc@2134 2296 body_summary->get_scan_rs_seq(),
johnc@2134 2297 body_summary->get_obj_copy_seq()
johnc@2134 2298 };
johnc@2134 2299 calc_other_times_ms = NumberSeq(summary->get_total_seq(),
johnc@2134 2300 6, other_parts);
johnc@2134 2301 }
johnc@2134 2302 check_other_times(1, summary->get_other_seq(), &calc_other_times_ms);
ysr@777 2303 }
ysr@777 2304 }
ysr@777 2305 } else {
brutisso@2645 2306 LineBuffer(1).append_and_print_cr("none");
ysr@777 2307 }
brutisso@2645 2308 LineBuffer(0).append_and_print_cr("");
ysr@777 2309 }
ysr@777 2310
ysr@777 2311 void G1CollectorPolicy::print_tracing_info() const {
ysr@777 2312 if (TraceGen0Time) {
ysr@777 2313 gclog_or_tty->print_cr("ALL PAUSES");
ysr@777 2314 print_summary_sd(0, "Total", _all_pause_times_ms);
ysr@777 2315 gclog_or_tty->print_cr("");
ysr@777 2316 gclog_or_tty->print_cr("");
ysr@777 2317 gclog_or_tty->print_cr(" Full Young GC Pauses: %8d", _full_young_pause_num);
ysr@777 2318 gclog_or_tty->print_cr(" Partial Young GC Pauses: %8d", _partial_young_pause_num);
ysr@777 2319 gclog_or_tty->print_cr("");
ysr@777 2320
apetrusenko@1112 2321 gclog_or_tty->print_cr("EVACUATION PAUSES");
apetrusenko@1112 2322 print_summary(_summary);
ysr@777 2323
ysr@777 2324 gclog_or_tty->print_cr("MISC");
ysr@777 2325 print_summary_sd(0, "Stop World", _all_stop_world_times_ms);
ysr@777 2326 print_summary_sd(0, "Yields", _all_yield_times_ms);
ysr@777 2327 for (int i = 0; i < _aux_num; ++i) {
ysr@777 2328 if (_all_aux_times_ms[i].num() > 0) {
ysr@777 2329 char buffer[96];
ysr@777 2330 sprintf(buffer, "Aux%d", i);
ysr@777 2331 print_summary_sd(0, buffer, &_all_aux_times_ms[i]);
ysr@777 2332 }
ysr@777 2333 }
ysr@777 2334
ysr@777 2335 size_t all_region_num = _region_num_young + _region_num_tenured;
ysr@777 2336 gclog_or_tty->print_cr(" New Regions %8d, Young %8d (%6.2lf%%), "
ysr@777 2337 "Tenured %8d (%6.2lf%%)",
ysr@777 2338 all_region_num,
ysr@777 2339 _region_num_young,
ysr@777 2340 (double) _region_num_young / (double) all_region_num * 100.0,
ysr@777 2341 _region_num_tenured,
ysr@777 2342 (double) _region_num_tenured / (double) all_region_num * 100.0);
ysr@777 2343 }
ysr@777 2344 if (TraceGen1Time) {
ysr@777 2345 if (_all_full_gc_times_ms->num() > 0) {
ysr@777 2346 gclog_or_tty->print("\n%4d full_gcs: total time = %8.2f s",
ysr@777 2347 _all_full_gc_times_ms->num(),
ysr@777 2348 _all_full_gc_times_ms->sum() / 1000.0);
ysr@777 2349 gclog_or_tty->print_cr(" (avg = %8.2fms).", _all_full_gc_times_ms->avg());
ysr@777 2350 gclog_or_tty->print_cr(" [std. dev = %8.2f ms, max = %8.2f ms]",
ysr@777 2351 _all_full_gc_times_ms->sd(),
ysr@777 2352 _all_full_gc_times_ms->maximum());
ysr@777 2353 }
ysr@777 2354 }
ysr@777 2355 }
ysr@777 2356
ysr@777 2357 void G1CollectorPolicy::print_yg_surv_rate_info() const {
ysr@777 2358 #ifndef PRODUCT
ysr@777 2359 _short_lived_surv_rate_group->print_surv_rate_summary();
ysr@777 2360 // add this call for any other surv rate groups
ysr@777 2361 #endif // PRODUCT
ysr@777 2362 }
ysr@777 2363
tonyp@3114 2364 void G1CollectorPolicy::update_region_num(bool young) {
tonyp@2315 2365 if (young) {
ysr@777 2366 ++_region_num_young;
ysr@777 2367 } else {
ysr@777 2368 ++_region_num_tenured;
ysr@777 2369 }
ysr@777 2370 }
ysr@777 2371
ysr@777 2372 #ifndef PRODUCT
ysr@777 2373 // for debugging, bit of a hack...
ysr@777 2374 static char*
ysr@777 2375 region_num_to_mbs(int length) {
ysr@777 2376 static char buffer[64];
ysr@777 2377 double bytes = (double) (length * HeapRegion::GrainBytes);
ysr@777 2378 double mbs = bytes / (double) (1024 * 1024);
ysr@777 2379 sprintf(buffer, "%7.2lfMB", mbs);
ysr@777 2380 return buffer;
ysr@777 2381 }
ysr@777 2382 #endif // PRODUCT
ysr@777 2383
apetrusenko@980 2384 size_t G1CollectorPolicy::max_regions(int purpose) {
ysr@777 2385 switch (purpose) {
ysr@777 2386 case GCAllocForSurvived:
apetrusenko@980 2387 return _max_survivor_regions;
ysr@777 2388 case GCAllocForTenured:
apetrusenko@980 2389 return REGIONS_UNLIMITED;
ysr@777 2390 default:
apetrusenko@980 2391 ShouldNotReachHere();
apetrusenko@980 2392 return REGIONS_UNLIMITED;
ysr@777 2393 };
ysr@777 2394 }
ysr@777 2395
tonyp@3119 2396 void G1CollectorPolicy::update_max_gc_locker_expansion() {
tonyp@2333 2397 size_t expansion_region_num = 0;
tonyp@2333 2398 if (GCLockerEdenExpansionPercent > 0) {
tonyp@2333 2399 double perc = (double) GCLockerEdenExpansionPercent / 100.0;
tonyp@2333 2400 double expansion_region_num_d = perc * (double) _young_list_target_length;
tonyp@2333 2401 // We use ceiling so that if expansion_region_num_d is > 0.0 (but
tonyp@2333 2402 // less than 1.0) we'll get 1.
tonyp@2333 2403 expansion_region_num = (size_t) ceil(expansion_region_num_d);
tonyp@2333 2404 } else {
tonyp@2333 2405 assert(expansion_region_num == 0, "sanity");
tonyp@2333 2406 }
tonyp@2333 2407 _young_list_max_length = _young_list_target_length + expansion_region_num;
tonyp@2333 2408 assert(_young_list_target_length <= _young_list_max_length, "post-condition");
tonyp@2333 2409 }
tonyp@2333 2410
apetrusenko@980 2411 // Calculates survivor space parameters.
tonyp@3119 2412 void G1CollectorPolicy::update_survivors_policy() {
tonyp@3119 2413 double max_survivor_regions_d =
tonyp@3119 2414 (double) _young_list_target_length / (double) SurvivorRatio;
tonyp@3119 2415 // We use ceiling so that if max_survivor_regions_d is > 0.0 (but
tonyp@3119 2416 // smaller than 1.0) we'll get 1.
tonyp@3119 2417 _max_survivor_regions = (size_t) ceil(max_survivor_regions_d);
tonyp@3119 2418
tonyp@3066 2419 _tenuring_threshold = _survivors_age_table.compute_tenuring_threshold(
apetrusenko@980 2420 HeapRegion::GrainWords * _max_survivor_regions);
apetrusenko@980 2421 }
apetrusenko@980 2422
ysr@777 2423 #ifndef PRODUCT
ysr@777 2424 class HRSortIndexIsOKClosure: public HeapRegionClosure {
ysr@777 2425 CollectionSetChooser* _chooser;
ysr@777 2426 public:
ysr@777 2427 HRSortIndexIsOKClosure(CollectionSetChooser* chooser) :
ysr@777 2428 _chooser(chooser) {}
ysr@777 2429
ysr@777 2430 bool doHeapRegion(HeapRegion* r) {
ysr@777 2431 if (!r->continuesHumongous()) {
ysr@777 2432 assert(_chooser->regionProperlyOrdered(r), "Ought to be.");
ysr@777 2433 }
ysr@777 2434 return false;
ysr@777 2435 }
ysr@777 2436 };
ysr@777 2437
tonyp@3209 2438 bool G1CollectorPolicy::assertMarkedBytesDataOK() {
ysr@777 2439 HRSortIndexIsOKClosure cl(_collectionSetChooser);
ysr@777 2440 _g1->heap_region_iterate(&cl);
ysr@777 2441 return true;
ysr@777 2442 }
ysr@777 2443 #endif
ysr@777 2444
tonyp@3114 2445 bool G1CollectorPolicy::force_initial_mark_if_outside_cycle(
tonyp@3114 2446 GCCause::Cause gc_cause) {
tonyp@2011 2447 bool during_cycle = _g1->concurrent_mark()->cmThread()->during_cycle();
tonyp@2011 2448 if (!during_cycle) {
tonyp@3114 2449 ergo_verbose1(ErgoConcCycles,
tonyp@3114 2450 "request concurrent cycle initiation",
tonyp@3114 2451 ergo_format_reason("requested by GC cause")
tonyp@3114 2452 ergo_format_str("GC cause"),
tonyp@3114 2453 GCCause::to_string(gc_cause));
tonyp@2011 2454 set_initiate_conc_mark_if_possible();
tonyp@2011 2455 return true;
tonyp@2011 2456 } else {
tonyp@3114 2457 ergo_verbose1(ErgoConcCycles,
tonyp@3114 2458 "do not request concurrent cycle initiation",
tonyp@3114 2459 ergo_format_reason("concurrent cycle already in progress")
tonyp@3114 2460 ergo_format_str("GC cause"),
tonyp@3114 2461 GCCause::to_string(gc_cause));
tonyp@2011 2462 return false;
tonyp@2011 2463 }
tonyp@2011 2464 }
tonyp@2011 2465
ysr@777 2466 void
tonyp@1794 2467 G1CollectorPolicy::decide_on_conc_mark_initiation() {
tonyp@1794 2468 // We are about to decide on whether this pause will be an
tonyp@1794 2469 // initial-mark pause.
tonyp@1794 2470
tonyp@1794 2471 // First, during_initial_mark_pause() should not be already set. We
tonyp@1794 2472 // will set it here if we have to. However, it should be cleared by
tonyp@1794 2473 // the end of the pause (it's only set for the duration of an
tonyp@1794 2474 // initial-mark pause).
tonyp@1794 2475 assert(!during_initial_mark_pause(), "pre-condition");
tonyp@1794 2476
tonyp@1794 2477 if (initiate_conc_mark_if_possible()) {
tonyp@1794 2478 // We had noticed on a previous pause that the heap occupancy has
tonyp@1794 2479 // gone over the initiating threshold and we should start a
tonyp@1794 2480 // concurrent marking cycle. So we might initiate one.
tonyp@1794 2481
tonyp@1794 2482 bool during_cycle = _g1->concurrent_mark()->cmThread()->during_cycle();
tonyp@1794 2483 if (!during_cycle) {
tonyp@1794 2484 // The concurrent marking thread is not "during a cycle", i.e.,
tonyp@1794 2485 // it has completed the last one. So we can go ahead and
tonyp@1794 2486 // initiate a new cycle.
tonyp@1794 2487
tonyp@1794 2488 set_during_initial_mark_pause();
johnc@3178 2489 // We do not allow non-full young GCs during marking.
johnc@3178 2490 if (!full_young_gcs()) {
johnc@3178 2491 set_full_young_gcs(true);
johnc@3178 2492 ergo_verbose0(ErgoPartiallyYoungGCs,
johnc@3178 2493 "end partially-young GCs",
johnc@3178 2494 ergo_format_reason("concurrent cycle is about to start"));
johnc@3178 2495 }
tonyp@1794 2496
tonyp@1794 2497 // And we can now clear initiate_conc_mark_if_possible() as
tonyp@1794 2498 // we've already acted on it.
tonyp@1794 2499 clear_initiate_conc_mark_if_possible();
tonyp@3114 2500
tonyp@3114 2501 ergo_verbose0(ErgoConcCycles,
tonyp@3114 2502 "initiate concurrent cycle",
tonyp@3114 2503 ergo_format_reason("concurrent cycle initiation requested"));
tonyp@1794 2504 } else {
tonyp@1794 2505 // The concurrent marking thread is still finishing up the
tonyp@1794 2506 // previous cycle. If we start one right now the two cycles
tonyp@1794 2507 // overlap. In particular, the concurrent marking thread might
tonyp@1794 2508 // be in the process of clearing the next marking bitmap (which
tonyp@1794 2509 // we will use for the next cycle if we start one). Starting a
tonyp@1794 2510 // cycle now will be bad given that parts of the marking
tonyp@1794 2511 // information might get cleared by the marking thread. And we
tonyp@1794 2512 // cannot wait for the marking thread to finish the cycle as it
tonyp@1794 2513 // periodically yields while clearing the next marking bitmap
tonyp@1794 2514 // and, if it's in a yield point, it's waiting for us to
tonyp@1794 2515 // finish. So, at this point we will not start a cycle and we'll
tonyp@1794 2516 // let the concurrent marking thread complete the last one.
tonyp@3114 2517 ergo_verbose0(ErgoConcCycles,
tonyp@3114 2518 "do not initiate concurrent cycle",
tonyp@3114 2519 ergo_format_reason("concurrent cycle already in progress"));
tonyp@1794 2520 }
tonyp@1794 2521 }
tonyp@1794 2522 }
tonyp@1794 2523
ysr@777 2524 class KnownGarbageClosure: public HeapRegionClosure {
ysr@777 2525 CollectionSetChooser* _hrSorted;
ysr@777 2526
ysr@777 2527 public:
ysr@777 2528 KnownGarbageClosure(CollectionSetChooser* hrSorted) :
ysr@777 2529 _hrSorted(hrSorted)
ysr@777 2530 {}
ysr@777 2531
ysr@777 2532 bool doHeapRegion(HeapRegion* r) {
ysr@777 2533 // We only include humongous regions in collection
ysr@777 2534 // sets when concurrent mark shows that their contained object is
ysr@777 2535 // unreachable.
ysr@777 2536
ysr@777 2537 // Do we have any marking information for this region?
ysr@777 2538 if (r->is_marked()) {
ysr@777 2539 // We don't include humongous regions in collection
ysr@777 2540 // sets because we collect them immediately at the end of a marking
ysr@777 2541 // cycle. We also don't include young regions because we *must*
ysr@777 2542 // include them in the next collection pause.
ysr@777 2543 if (!r->isHumongous() && !r->is_young()) {
ysr@777 2544 _hrSorted->addMarkedHeapRegion(r);
ysr@777 2545 }
ysr@777 2546 }
ysr@777 2547 return false;
ysr@777 2548 }
ysr@777 2549 };
ysr@777 2550
ysr@777 2551 class ParKnownGarbageHRClosure: public HeapRegionClosure {
ysr@777 2552 CollectionSetChooser* _hrSorted;
ysr@777 2553 jint _marked_regions_added;
ysr@777 2554 jint _chunk_size;
ysr@777 2555 jint _cur_chunk_idx;
ysr@777 2556 jint _cur_chunk_end; // Cur chunk [_cur_chunk_idx, _cur_chunk_end)
ysr@777 2557 int _worker;
ysr@777 2558 int _invokes;
ysr@777 2559
ysr@777 2560 void get_new_chunk() {
ysr@777 2561 _cur_chunk_idx = _hrSorted->getParMarkedHeapRegionChunk(_chunk_size);
ysr@777 2562 _cur_chunk_end = _cur_chunk_idx + _chunk_size;
ysr@777 2563 }
ysr@777 2564 void add_region(HeapRegion* r) {
ysr@777 2565 if (_cur_chunk_idx == _cur_chunk_end) {
ysr@777 2566 get_new_chunk();
ysr@777 2567 }
ysr@777 2568 assert(_cur_chunk_idx < _cur_chunk_end, "postcondition");
ysr@777 2569 _hrSorted->setMarkedHeapRegion(_cur_chunk_idx, r);
ysr@777 2570 _marked_regions_added++;
ysr@777 2571 _cur_chunk_idx++;
ysr@777 2572 }
ysr@777 2573
ysr@777 2574 public:
ysr@777 2575 ParKnownGarbageHRClosure(CollectionSetChooser* hrSorted,
ysr@777 2576 jint chunk_size,
ysr@777 2577 int worker) :
ysr@777 2578 _hrSorted(hrSorted), _chunk_size(chunk_size), _worker(worker),
ysr@777 2579 _marked_regions_added(0), _cur_chunk_idx(0), _cur_chunk_end(0),
ysr@777 2580 _invokes(0)
ysr@777 2581 {}
ysr@777 2582
ysr@777 2583 bool doHeapRegion(HeapRegion* r) {
ysr@777 2584 // We only include humongous regions in collection
ysr@777 2585 // sets when concurrent mark shows that their contained object is
ysr@777 2586 // unreachable.
ysr@777 2587 _invokes++;
ysr@777 2588
ysr@777 2589 // Do we have any marking information for this region?
ysr@777 2590 if (r->is_marked()) {
ysr@777 2591 // We don't include humongous regions in collection
ysr@777 2592 // sets because we collect them immediately at the end of a marking
ysr@777 2593 // cycle.
ysr@777 2594 // We also do not include young regions in collection sets
ysr@777 2595 if (!r->isHumongous() && !r->is_young()) {
ysr@777 2596 add_region(r);
ysr@777 2597 }
ysr@777 2598 }
ysr@777 2599 return false;
ysr@777 2600 }
ysr@777 2601 jint marked_regions_added() { return _marked_regions_added; }
ysr@777 2602 int invokes() { return _invokes; }
ysr@777 2603 };
ysr@777 2604
ysr@777 2605 class ParKnownGarbageTask: public AbstractGangTask {
ysr@777 2606 CollectionSetChooser* _hrSorted;
ysr@777 2607 jint _chunk_size;
ysr@777 2608 G1CollectedHeap* _g1;
ysr@777 2609 public:
ysr@777 2610 ParKnownGarbageTask(CollectionSetChooser* hrSorted, jint chunk_size) :
ysr@777 2611 AbstractGangTask("ParKnownGarbageTask"),
ysr@777 2612 _hrSorted(hrSorted), _chunk_size(chunk_size),
ysr@777 2613 _g1(G1CollectedHeap::heap())
ysr@777 2614 {}
ysr@777 2615
ysr@777 2616 void work(int i) {
ysr@777 2617 ParKnownGarbageHRClosure parKnownGarbageCl(_hrSorted, _chunk_size, i);
ysr@777 2618 // Back to zero for the claim value.
tonyp@790 2619 _g1->heap_region_par_iterate_chunked(&parKnownGarbageCl, i,
tonyp@790 2620 HeapRegion::InitialClaimValue);
ysr@777 2621 jint regions_added = parKnownGarbageCl.marked_regions_added();
ysr@777 2622 _hrSorted->incNumMarkedHeapRegions(regions_added);
ysr@777 2623 if (G1PrintParCleanupStats) {
brutisso@2645 2624 gclog_or_tty->print_cr(" Thread %d called %d times, added %d regions to list.",
ysr@777 2625 i, parKnownGarbageCl.invokes(), regions_added);
ysr@777 2626 }
ysr@777 2627 }
ysr@777 2628 };
ysr@777 2629
ysr@777 2630 void
tonyp@3209 2631 G1CollectorPolicy::record_concurrent_mark_cleanup_end() {
tonyp@3209 2632 double start_sec;
tonyp@3209 2633 if (G1PrintParCleanupStats) {
tonyp@3209 2634 start_sec = os::elapsedTime();
tonyp@3209 2635 }
ysr@777 2636
ysr@777 2637 _collectionSetChooser->clearMarkedHeapRegions();
tonyp@3209 2638 double clear_marked_end_sec;
ysr@777 2639 if (G1PrintParCleanupStats) {
tonyp@3209 2640 clear_marked_end_sec = os::elapsedTime();
tonyp@3209 2641 gclog_or_tty->print_cr(" clear marked regions: %8.3f ms.",
tonyp@3209 2642 (clear_marked_end_sec - start_sec) * 1000.0);
ysr@777 2643 }
tonyp@3209 2644
jmasa@2188 2645 if (G1CollectedHeap::use_parallel_gc_threads()) {
ysr@777 2646 const size_t OverpartitionFactor = 4;
kvn@1926 2647 const size_t MinWorkUnit = 8;
kvn@1926 2648 const size_t WorkUnit =
ysr@777 2649 MAX2(_g1->n_regions() / (ParallelGCThreads * OverpartitionFactor),
kvn@1926 2650 MinWorkUnit);
ysr@777 2651 _collectionSetChooser->prepareForAddMarkedHeapRegionsPar(_g1->n_regions(),
kvn@1926 2652 WorkUnit);
ysr@777 2653 ParKnownGarbageTask parKnownGarbageTask(_collectionSetChooser,
kvn@1926 2654 (int) WorkUnit);
ysr@777 2655 _g1->workers()->run_task(&parKnownGarbageTask);
tonyp@790 2656
tonyp@790 2657 assert(_g1->check_heap_region_claim_values(HeapRegion::InitialClaimValue),
tonyp@790 2658 "sanity check");
ysr@777 2659 } else {
ysr@777 2660 KnownGarbageClosure knownGarbagecl(_collectionSetChooser);
ysr@777 2661 _g1->heap_region_iterate(&knownGarbagecl);
ysr@777 2662 }
tonyp@3209 2663 double known_garbage_end_sec;
ysr@777 2664 if (G1PrintParCleanupStats) {
tonyp@3209 2665 known_garbage_end_sec = os::elapsedTime();
ysr@777 2666 gclog_or_tty->print_cr(" compute known garbage: %8.3f ms.",
tonyp@3209 2667 (known_garbage_end_sec - clear_marked_end_sec) * 1000.0);
ysr@777 2668 }
tonyp@3209 2669
ysr@777 2670 _collectionSetChooser->sortMarkedHeapRegions();
tonyp@3209 2671 double end_sec = os::elapsedTime();
ysr@777 2672 if (G1PrintParCleanupStats) {
ysr@777 2673 gclog_or_tty->print_cr(" sorting: %8.3f ms.",
tonyp@3209 2674 (end_sec - known_garbage_end_sec) * 1000.0);
ysr@777 2675 }
ysr@777 2676
tonyp@3209 2677 double elapsed_time_ms = (end_sec - _mark_cleanup_start_sec) * 1000.0;
tonyp@3209 2678 _concurrent_mark_cleanup_times_ms->add(elapsed_time_ms);
tonyp@3209 2679 _cur_mark_stop_world_time_ms += elapsed_time_ms;
tonyp@3209 2680 _prev_collection_pause_end_ms += elapsed_time_ms;
tonyp@3209 2681 _mmu_tracker->add_pause(_mark_cleanup_start_sec, end_sec, true);
ysr@777 2682 }
ysr@777 2683
johnc@1829 2684 // Add the heap region at the head of the non-incremental collection set
ysr@777 2685 void G1CollectorPolicy::
ysr@777 2686 add_to_collection_set(HeapRegion* hr) {
johnc@1829 2687 assert(_inc_cset_build_state == Active, "Precondition");
johnc@1829 2688 assert(!hr->is_young(), "non-incremental add of young region");
johnc@1829 2689
ysr@777 2690 if (_g1->mark_in_progress())
ysr@777 2691 _g1->concurrent_mark()->registerCSetRegion(hr);
ysr@777 2692
johnc@1829 2693 assert(!hr->in_collection_set(), "should not already be in the CSet");
ysr@777 2694 hr->set_in_collection_set(true);
ysr@777 2695 hr->set_next_in_collection_set(_collection_set);
ysr@777 2696 _collection_set = hr;
ysr@777 2697 _collection_set_size++;
ysr@777 2698 _collection_set_bytes_used_before += hr->used();
tonyp@961 2699 _g1->register_region_with_in_cset_fast_test(hr);
ysr@777 2700 }
ysr@777 2701
johnc@1829 2702 // Initialize the per-collection-set information
johnc@1829 2703 void G1CollectorPolicy::start_incremental_cset_building() {
johnc@1829 2704 assert(_inc_cset_build_state == Inactive, "Precondition");
johnc@1829 2705
johnc@1829 2706 _inc_cset_head = NULL;
johnc@1829 2707 _inc_cset_tail = NULL;
johnc@1829 2708 _inc_cset_size = 0;
johnc@1829 2709 _inc_cset_bytes_used_before = 0;
johnc@1829 2710
brutisso@3065 2711 _inc_cset_young_index = 0;
johnc@1829 2712
johnc@1829 2713 _inc_cset_max_finger = 0;
johnc@1829 2714 _inc_cset_recorded_young_bytes = 0;
johnc@1829 2715 _inc_cset_recorded_rs_lengths = 0;
johnc@1829 2716 _inc_cset_predicted_elapsed_time_ms = 0;
johnc@1829 2717 _inc_cset_predicted_bytes_to_copy = 0;
johnc@1829 2718 _inc_cset_build_state = Active;
johnc@1829 2719 }
johnc@1829 2720
johnc@1829 2721 void G1CollectorPolicy::add_to_incremental_cset_info(HeapRegion* hr, size_t rs_length) {
johnc@1829 2722 // This routine is used when:
johnc@1829 2723 // * adding survivor regions to the incremental cset at the end of an
johnc@1829 2724 // evacuation pause,
johnc@1829 2725 // * adding the current allocation region to the incremental cset
johnc@1829 2726 // when it is retired, and
johnc@1829 2727 // * updating existing policy information for a region in the
johnc@1829 2728 // incremental cset via young list RSet sampling.
johnc@1829 2729 // Therefore this routine may be called at a safepoint by the
johnc@1829 2730 // VM thread, or in-between safepoints by mutator threads (when
johnc@1829 2731 // retiring the current allocation region) or a concurrent
johnc@1829 2732 // refine thread (RSet sampling).
johnc@1829 2733
johnc@1829 2734 double region_elapsed_time_ms = predict_region_elapsed_time_ms(hr, true);
johnc@1829 2735 size_t used_bytes = hr->used();
johnc@1829 2736
johnc@1829 2737 _inc_cset_recorded_rs_lengths += rs_length;
johnc@1829 2738 _inc_cset_predicted_elapsed_time_ms += region_elapsed_time_ms;
johnc@1829 2739
johnc@1829 2740 _inc_cset_bytes_used_before += used_bytes;
johnc@1829 2741
johnc@1829 2742 // Cache the values we have added to the aggregated informtion
johnc@1829 2743 // in the heap region in case we have to remove this region from
johnc@1829 2744 // the incremental collection set, or it is updated by the
johnc@1829 2745 // rset sampling code
johnc@1829 2746 hr->set_recorded_rs_length(rs_length);
johnc@1829 2747 hr->set_predicted_elapsed_time_ms(region_elapsed_time_ms);
johnc@1829 2748
johnc@1829 2749 #if PREDICTIONS_VERBOSE
johnc@1829 2750 size_t bytes_to_copy = predict_bytes_to_copy(hr);
johnc@1829 2751 _inc_cset_predicted_bytes_to_copy += bytes_to_copy;
johnc@1829 2752
johnc@1829 2753 // Record the number of bytes used in this region
johnc@1829 2754 _inc_cset_recorded_young_bytes += used_bytes;
johnc@1829 2755
johnc@1829 2756 // Cache the values we have added to the aggregated informtion
johnc@1829 2757 // in the heap region in case we have to remove this region from
johnc@1829 2758 // the incremental collection set, or it is updated by the
johnc@1829 2759 // rset sampling code
johnc@1829 2760 hr->set_predicted_bytes_to_copy(bytes_to_copy);
johnc@1829 2761 #endif // PREDICTIONS_VERBOSE
johnc@1829 2762 }
johnc@1829 2763
johnc@1829 2764 void G1CollectorPolicy::remove_from_incremental_cset_info(HeapRegion* hr) {
johnc@1829 2765 // This routine is currently only called as part of the updating of
johnc@1829 2766 // existing policy information for regions in the incremental cset that
johnc@1829 2767 // is performed by the concurrent refine thread(s) as part of young list
johnc@1829 2768 // RSet sampling. Therefore we should not be at a safepoint.
johnc@1829 2769
johnc@1829 2770 assert(!SafepointSynchronize::is_at_safepoint(), "should not be at safepoint");
johnc@1829 2771 assert(hr->is_young(), "it should be");
johnc@1829 2772
johnc@1829 2773 size_t used_bytes = hr->used();
johnc@1829 2774 size_t old_rs_length = hr->recorded_rs_length();
johnc@1829 2775 double old_elapsed_time_ms = hr->predicted_elapsed_time_ms();
johnc@1829 2776
johnc@1829 2777 // Subtract the old recorded/predicted policy information for
johnc@1829 2778 // the given heap region from the collection set info.
johnc@1829 2779 _inc_cset_recorded_rs_lengths -= old_rs_length;
johnc@1829 2780 _inc_cset_predicted_elapsed_time_ms -= old_elapsed_time_ms;
johnc@1829 2781
johnc@1829 2782 _inc_cset_bytes_used_before -= used_bytes;
johnc@1829 2783
johnc@1829 2784 // Clear the values cached in the heap region
johnc@1829 2785 hr->set_recorded_rs_length(0);
johnc@1829 2786 hr->set_predicted_elapsed_time_ms(0);
johnc@1829 2787
johnc@1829 2788 #if PREDICTIONS_VERBOSE
johnc@1829 2789 size_t old_predicted_bytes_to_copy = hr->predicted_bytes_to_copy();
johnc@1829 2790 _inc_cset_predicted_bytes_to_copy -= old_predicted_bytes_to_copy;
johnc@1829 2791
johnc@1829 2792 // Subtract the number of bytes used in this region
johnc@1829 2793 _inc_cset_recorded_young_bytes -= used_bytes;
johnc@1829 2794
johnc@1829 2795 // Clear the values cached in the heap region
johnc@1829 2796 hr->set_predicted_bytes_to_copy(0);
johnc@1829 2797 #endif // PREDICTIONS_VERBOSE
johnc@1829 2798 }
johnc@1829 2799
johnc@1829 2800 void G1CollectorPolicy::update_incremental_cset_info(HeapRegion* hr, size_t new_rs_length) {
johnc@1829 2801 // Update the collection set information that is dependent on the new RS length
johnc@1829 2802 assert(hr->is_young(), "Precondition");
johnc@1829 2803
johnc@1829 2804 remove_from_incremental_cset_info(hr);
johnc@1829 2805 add_to_incremental_cset_info(hr, new_rs_length);
johnc@1829 2806 }
johnc@1829 2807
johnc@1829 2808 void G1CollectorPolicy::add_region_to_incremental_cset_common(HeapRegion* hr) {
johnc@1829 2809 assert( hr->is_young(), "invariant");
johnc@1829 2810 assert( hr->young_index_in_cset() == -1, "invariant" );
johnc@1829 2811 assert(_inc_cset_build_state == Active, "Precondition");
johnc@1829 2812
johnc@1829 2813 // We need to clear and set the cached recorded/cached collection set
johnc@1829 2814 // information in the heap region here (before the region gets added
johnc@1829 2815 // to the collection set). An individual heap region's cached values
johnc@1829 2816 // are calculated, aggregated with the policy collection set info,
johnc@1829 2817 // and cached in the heap region here (initially) and (subsequently)
johnc@1829 2818 // by the Young List sampling code.
johnc@1829 2819
johnc@1829 2820 size_t rs_length = hr->rem_set()->occupied();
johnc@1829 2821 add_to_incremental_cset_info(hr, rs_length);
johnc@1829 2822
johnc@1829 2823 HeapWord* hr_end = hr->end();
johnc@1829 2824 _inc_cset_max_finger = MAX2(_inc_cset_max_finger, hr_end);
johnc@1829 2825
johnc@1829 2826 assert(!hr->in_collection_set(), "invariant");
johnc@1829 2827 hr->set_in_collection_set(true);
johnc@1829 2828 assert( hr->next_in_collection_set() == NULL, "invariant");
johnc@1829 2829
johnc@1829 2830 _inc_cset_size++;
johnc@1829 2831 _g1->register_region_with_in_cset_fast_test(hr);
johnc@1829 2832
johnc@1829 2833 hr->set_young_index_in_cset((int) _inc_cset_young_index);
johnc@1829 2834 ++_inc_cset_young_index;
johnc@1829 2835 }
johnc@1829 2836
johnc@1829 2837 // Add the region at the RHS of the incremental cset
johnc@1829 2838 void G1CollectorPolicy::add_region_to_incremental_cset_rhs(HeapRegion* hr) {
johnc@1829 2839 // We should only ever be appending survivors at the end of a pause
johnc@1829 2840 assert( hr->is_survivor(), "Logic");
johnc@1829 2841
johnc@1829 2842 // Do the 'common' stuff
johnc@1829 2843 add_region_to_incremental_cset_common(hr);
johnc@1829 2844
johnc@1829 2845 // Now add the region at the right hand side
johnc@1829 2846 if (_inc_cset_tail == NULL) {
johnc@1829 2847 assert(_inc_cset_head == NULL, "invariant");
johnc@1829 2848 _inc_cset_head = hr;
johnc@1829 2849 } else {
johnc@1829 2850 _inc_cset_tail->set_next_in_collection_set(hr);
johnc@1829 2851 }
johnc@1829 2852 _inc_cset_tail = hr;
johnc@1829 2853 }
johnc@1829 2854
johnc@1829 2855 // Add the region to the LHS of the incremental cset
johnc@1829 2856 void G1CollectorPolicy::add_region_to_incremental_cset_lhs(HeapRegion* hr) {
johnc@1829 2857 // Survivors should be added to the RHS at the end of a pause
johnc@1829 2858 assert(!hr->is_survivor(), "Logic");
johnc@1829 2859
johnc@1829 2860 // Do the 'common' stuff
johnc@1829 2861 add_region_to_incremental_cset_common(hr);
johnc@1829 2862
johnc@1829 2863 // Add the region at the left hand side
johnc@1829 2864 hr->set_next_in_collection_set(_inc_cset_head);
johnc@1829 2865 if (_inc_cset_head == NULL) {
johnc@1829 2866 assert(_inc_cset_tail == NULL, "Invariant");
johnc@1829 2867 _inc_cset_tail = hr;
johnc@1829 2868 }
johnc@1829 2869 _inc_cset_head = hr;
johnc@1829 2870 }
johnc@1829 2871
johnc@1829 2872 #ifndef PRODUCT
johnc@1829 2873 void G1CollectorPolicy::print_collection_set(HeapRegion* list_head, outputStream* st) {
johnc@1829 2874 assert(list_head == inc_cset_head() || list_head == collection_set(), "must be");
johnc@1829 2875
johnc@1829 2876 st->print_cr("\nCollection_set:");
johnc@1829 2877 HeapRegion* csr = list_head;
johnc@1829 2878 while (csr != NULL) {
johnc@1829 2879 HeapRegion* next = csr->next_in_collection_set();
johnc@1829 2880 assert(csr->in_collection_set(), "bad CS");
johnc@1829 2881 st->print_cr(" [%08x-%08x], t: %08x, P: %08x, N: %08x, C: %08x, "
johnc@1829 2882 "age: %4d, y: %d, surv: %d",
johnc@1829 2883 csr->bottom(), csr->end(),
johnc@1829 2884 csr->top(),
johnc@1829 2885 csr->prev_top_at_mark_start(),
johnc@1829 2886 csr->next_top_at_mark_start(),
johnc@1829 2887 csr->top_at_conc_mark_count(),
johnc@1829 2888 csr->age_in_surv_rate_group_cond(),
johnc@1829 2889 csr->is_young(),
johnc@1829 2890 csr->is_survivor());
johnc@1829 2891 csr = next;
johnc@1829 2892 }
johnc@1829 2893 }
johnc@1829 2894 #endif // !PRODUCT
johnc@1829 2895
tonyp@3209 2896 void G1CollectorPolicy::choose_collection_set(double target_pause_time_ms) {
johnc@1829 2897 // Set this here - in case we're not doing young collections.
johnc@1829 2898 double non_young_start_time_sec = os::elapsedTime();
johnc@1829 2899
tonyp@3114 2900 YoungList* young_list = _g1->young_list();
tonyp@3114 2901
ysr@777 2902 start_recording_regions();
ysr@777 2903
tonyp@2011 2904 guarantee(target_pause_time_ms > 0.0,
tonyp@2011 2905 err_msg("target_pause_time_ms = %1.6lf should be positive",
tonyp@2011 2906 target_pause_time_ms));
tonyp@2011 2907 guarantee(_collection_set == NULL, "Precondition");
ysr@777 2908
ysr@777 2909 double base_time_ms = predict_base_elapsed_time_ms(_pending_cards);
ysr@777 2910 double predicted_pause_time_ms = base_time_ms;
ysr@777 2911
tonyp@2011 2912 double time_remaining_ms = target_pause_time_ms - base_time_ms;
ysr@777 2913
tonyp@3114 2914 ergo_verbose3(ErgoCSetConstruction | ErgoHigh,
tonyp@3114 2915 "start choosing CSet",
tonyp@3114 2916 ergo_format_ms("predicted base time")
tonyp@3114 2917 ergo_format_ms("remaining time")
tonyp@3114 2918 ergo_format_ms("target pause time"),
tonyp@3114 2919 base_time_ms, time_remaining_ms, target_pause_time_ms);
tonyp@3114 2920
ysr@777 2921 // the 10% and 50% values are arbitrary...
tonyp@3114 2922 double threshold = 0.10 * target_pause_time_ms;
tonyp@3114 2923 if (time_remaining_ms < threshold) {
tonyp@3114 2924 double prev_time_remaining_ms = time_remaining_ms;
tonyp@2011 2925 time_remaining_ms = 0.50 * target_pause_time_ms;
ysr@777 2926 _within_target = false;
tonyp@3114 2927 ergo_verbose3(ErgoCSetConstruction,
tonyp@3114 2928 "adjust remaining time",
tonyp@3114 2929 ergo_format_reason("remaining time lower than threshold")
tonyp@3114 2930 ergo_format_ms("remaining time")
tonyp@3114 2931 ergo_format_ms("threshold")
tonyp@3114 2932 ergo_format_ms("adjusted remaining time"),
tonyp@3114 2933 prev_time_remaining_ms, threshold, time_remaining_ms);
ysr@777 2934 } else {
ysr@777 2935 _within_target = true;
ysr@777 2936 }
ysr@777 2937
tonyp@3114 2938 size_t expansion_bytes = _g1->expansion_regions() * HeapRegion::GrainBytes;
tonyp@3114 2939
tonyp@3114 2940 HeapRegion* hr;
tonyp@3114 2941 double young_start_time_sec = os::elapsedTime();
ysr@777 2942
apetrusenko@1112 2943 _collection_set_bytes_used_before = 0;
apetrusenko@1112 2944 _collection_set_size = 0;
brutisso@3065 2945 _young_cset_length = 0;
brutisso@3065 2946 _last_young_gc_full = full_young_gcs() ? true : false;
brutisso@3065 2947
tonyp@3114 2948 if (_last_young_gc_full) {
brutisso@3065 2949 ++_full_young_pause_num;
tonyp@3114 2950 } else {
brutisso@3065 2951 ++_partial_young_pause_num;
tonyp@3114 2952 }
brutisso@3065 2953
brutisso@3065 2954 // The young list is laid with the survivor regions from the previous
brutisso@3065 2955 // pause are appended to the RHS of the young list, i.e.
brutisso@3065 2956 // [Newly Young Regions ++ Survivors from last pause].
brutisso@3065 2957
tonyp@3114 2958 size_t survivor_region_num = young_list->survivor_length();
tonyp@3114 2959 size_t eden_region_num = young_list->length() - survivor_region_num;
tonyp@3114 2960 size_t old_region_num = 0;
tonyp@3114 2961 hr = young_list->first_survivor_region();
brutisso@3065 2962 while (hr != NULL) {
brutisso@3065 2963 assert(hr->is_survivor(), "badly formed young list");
brutisso@3065 2964 hr->set_young();
brutisso@3065 2965 hr = hr->get_next_young_region();
brutisso@3065 2966 }
brutisso@3065 2967
tonyp@3114 2968 // Clear the fields that point to the survivor list - they are all young now.
tonyp@3114 2969 young_list->clear_survivors();
brutisso@3065 2970
brutisso@3065 2971 if (_g1->mark_in_progress())
brutisso@3065 2972 _g1->concurrent_mark()->register_collection_set_finger(_inc_cset_max_finger);
brutisso@3065 2973
brutisso@3065 2974 _young_cset_length = _inc_cset_young_index;
brutisso@3065 2975 _collection_set = _inc_cset_head;
brutisso@3065 2976 _collection_set_size = _inc_cset_size;
brutisso@3065 2977 _collection_set_bytes_used_before = _inc_cset_bytes_used_before;
brutisso@3065 2978 time_remaining_ms -= _inc_cset_predicted_elapsed_time_ms;
brutisso@3065 2979 predicted_pause_time_ms += _inc_cset_predicted_elapsed_time_ms;
brutisso@3065 2980
tonyp@3114 2981 ergo_verbose3(ErgoCSetConstruction | ErgoHigh,
tonyp@3114 2982 "add young regions to CSet",
tonyp@3114 2983 ergo_format_region("eden")
tonyp@3114 2984 ergo_format_region("survivors")
tonyp@3114 2985 ergo_format_ms("predicted young region time"),
tonyp@3114 2986 eden_region_num, survivor_region_num,
tonyp@3114 2987 _inc_cset_predicted_elapsed_time_ms);
tonyp@3114 2988
brutisso@3065 2989 // The number of recorded young regions is the incremental
brutisso@3065 2990 // collection set's current size
brutisso@3065 2991 set_recorded_young_regions(_inc_cset_size);
brutisso@3065 2992 set_recorded_rs_lengths(_inc_cset_recorded_rs_lengths);
brutisso@3065 2993 set_recorded_young_bytes(_inc_cset_recorded_young_bytes);
johnc@1829 2994 #if PREDICTIONS_VERBOSE
brutisso@3065 2995 set_predicted_bytes_to_copy(_inc_cset_predicted_bytes_to_copy);
johnc@1829 2996 #endif // PREDICTIONS_VERBOSE
johnc@1829 2997
tonyp@3114 2998 assert(_inc_cset_size == young_list->length(), "Invariant");
brutisso@3065 2999
brutisso@3065 3000 double young_end_time_sec = os::elapsedTime();
brutisso@3065 3001 _recorded_young_cset_choice_time_ms =
brutisso@3065 3002 (young_end_time_sec - young_start_time_sec) * 1000.0;
brutisso@3065 3003
brutisso@3065 3004 // We are doing young collections so reset this.
brutisso@3065 3005 non_young_start_time_sec = young_end_time_sec;
brutisso@3065 3006
brutisso@3065 3007 if (!full_young_gcs()) {
ysr@777 3008 bool should_continue = true;
ysr@777 3009 NumberSeq seq;
ysr@777 3010 double avg_prediction = 100000000000000000.0; // something very large
johnc@1829 3011
tonyp@3114 3012 size_t prev_collection_set_size = _collection_set_size;
tonyp@3114 3013 double prev_predicted_pause_time_ms = predicted_pause_time_ms;
ysr@777 3014 do {
ysr@777 3015 hr = _collectionSetChooser->getNextMarkedRegion(time_remaining_ms,
ysr@777 3016 avg_prediction);
apetrusenko@1112 3017 if (hr != NULL) {
ysr@777 3018 double predicted_time_ms = predict_region_elapsed_time_ms(hr, false);
ysr@777 3019 time_remaining_ms -= predicted_time_ms;
ysr@777 3020 predicted_pause_time_ms += predicted_time_ms;
ysr@777 3021 add_to_collection_set(hr);
johnc@1829 3022 record_non_young_cset_region(hr);
ysr@777 3023 seq.add(predicted_time_ms);
ysr@777 3024 avg_prediction = seq.avg() + seq.sd();
ysr@777 3025 }
tonyp@3114 3026
tonyp@3114 3027 should_continue = true;
tonyp@3114 3028 if (hr == NULL) {
tonyp@3114 3029 // No need for an ergo verbose message here,
tonyp@3114 3030 // getNextMarkRegion() does this when it returns NULL.
tonyp@3114 3031 should_continue = false;
tonyp@3114 3032 } else {
tonyp@3114 3033 if (adaptive_young_list_length()) {
tonyp@3114 3034 if (time_remaining_ms < 0.0) {
tonyp@3114 3035 ergo_verbose1(ErgoCSetConstruction,
tonyp@3114 3036 "stop adding old regions to CSet",
tonyp@3114 3037 ergo_format_reason("remaining time is lower than 0")
tonyp@3114 3038 ergo_format_ms("remaining time"),
tonyp@3114 3039 time_remaining_ms);
tonyp@3114 3040 should_continue = false;
tonyp@3114 3041 }
tonyp@3114 3042 } else {
tonyp@3126 3043 if (_collection_set_size >= _young_list_fixed_length) {
tonyp@3114 3044 ergo_verbose2(ErgoCSetConstruction,
tonyp@3114 3045 "stop adding old regions to CSet",
tonyp@3126 3046 ergo_format_reason("CSet length reached target")
tonyp@3114 3047 ergo_format_region("CSet")
tonyp@3114 3048 ergo_format_region("young target"),
tonyp@3114 3049 _collection_set_size, _young_list_fixed_length);
tonyp@3114 3050 should_continue = false;
tonyp@3114 3051 }
tonyp@3114 3052 }
tonyp@3114 3053 }
ysr@777 3054 } while (should_continue);
ysr@777 3055
ysr@777 3056 if (!adaptive_young_list_length() &&
tonyp@3114 3057 _collection_set_size < _young_list_fixed_length) {
tonyp@3114 3058 ergo_verbose2(ErgoCSetConstruction,
tonyp@3114 3059 "request partially-young GCs end",
tonyp@3114 3060 ergo_format_reason("CSet length lower than target")
tonyp@3114 3061 ergo_format_region("CSet")
tonyp@3114 3062 ergo_format_region("young target"),
tonyp@3114 3063 _collection_set_size, _young_list_fixed_length);
ysr@777 3064 _should_revert_to_full_young_gcs = true;
tonyp@3114 3065 }
tonyp@3114 3066
tonyp@3114 3067 old_region_num = _collection_set_size - prev_collection_set_size;
tonyp@3114 3068
tonyp@3114 3069 ergo_verbose2(ErgoCSetConstruction | ErgoHigh,
tonyp@3114 3070 "add old regions to CSet",
tonyp@3114 3071 ergo_format_region("old")
tonyp@3114 3072 ergo_format_ms("predicted old region time"),
tonyp@3114 3073 old_region_num,
tonyp@3114 3074 predicted_pause_time_ms - prev_predicted_pause_time_ms);
ysr@777 3075 }
ysr@777 3076
johnc@1829 3077 stop_incremental_cset_building();
johnc@1829 3078
ysr@777 3079 count_CS_bytes_used();
ysr@777 3080
ysr@777 3081 end_recording_regions();
ysr@777 3082
tonyp@3114 3083 ergo_verbose5(ErgoCSetConstruction,
tonyp@3114 3084 "finish choosing CSet",
tonyp@3114 3085 ergo_format_region("eden")
tonyp@3114 3086 ergo_format_region("survivors")
tonyp@3114 3087 ergo_format_region("old")
tonyp@3114 3088 ergo_format_ms("predicted pause time")
tonyp@3114 3089 ergo_format_ms("target pause time"),
tonyp@3114 3090 eden_region_num, survivor_region_num, old_region_num,
tonyp@3114 3091 predicted_pause_time_ms, target_pause_time_ms);
tonyp@3114 3092
ysr@777 3093 double non_young_end_time_sec = os::elapsedTime();
ysr@777 3094 _recorded_non_young_cset_choice_time_ms =
ysr@777 3095 (non_young_end_time_sec - non_young_start_time_sec) * 1000.0;
ysr@777 3096 }

mercurial