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

Tue, 20 Sep 2011 09:59:59 -0400

author
tonyp
date
Tue, 20 Sep 2011 09:59:59 -0400
changeset 3168
4f93f0d00802
parent 3126
f1b4e0e0bdad
child 3172
d912b598c6c3
permissions
-rw-r--r--

7059019: G1: add G1 support to the SA
Summary: Extend the SA to recognize the G1CollectedHeap and implement any code that's needed by our serviceability tools (jmap, jinfo, jstack, etc.) that depend on the SA.
Reviewed-by: never, poonam, 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@1325 155 #ifndef PRODUCT
ysr@777 156 _cur_clear_ct_time_ms(0.0),
johnc@1325 157 _min_clear_cc_time_ms(-1.0),
johnc@1325 158 _max_clear_cc_time_ms(-1.0),
johnc@1325 159 _cur_clear_cc_time_ms(0.0),
johnc@1325 160 _cum_clear_cc_time_ms(0.0),
johnc@1325 161 _num_cc_clears(0L),
johnc@1325 162 #endif
ysr@777 163
ysr@777 164 _region_num_young(0),
ysr@777 165 _region_num_tenured(0),
ysr@777 166 _prev_region_num_young(0),
ysr@777 167 _prev_region_num_tenured(0),
ysr@777 168
ysr@777 169 _aux_num(10),
ysr@777 170 _all_aux_times_ms(new NumberSeq[_aux_num]),
ysr@777 171 _cur_aux_start_times_ms(new double[_aux_num]),
ysr@777 172 _cur_aux_times_ms(new double[_aux_num]),
ysr@777 173 _cur_aux_times_set(new bool[_aux_num]),
ysr@777 174
ysr@777 175 _concurrent_mark_remark_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 176 _concurrent_mark_cleanup_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 177
ysr@777 178 // <NEW PREDICTION>
ysr@777 179
ysr@777 180 _alloc_rate_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 181 _prev_collection_pause_end_ms(0.0),
ysr@777 182 _pending_card_diff_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 183 _rs_length_diff_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 184 _cost_per_card_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 185 _fully_young_cards_per_entry_ratio_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 186 _partially_young_cards_per_entry_ratio_seq(
ysr@777 187 new TruncatedSeq(TruncatedSeqLength)),
ysr@777 188 _cost_per_entry_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 189 _partially_young_cost_per_entry_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 190 _cost_per_byte_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 191 _cost_per_byte_ms_during_cm_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 192 _constant_other_time_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 193 _young_other_cost_per_region_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 194 _non_young_other_cost_per_region_ms_seq(
ysr@777 195 new TruncatedSeq(TruncatedSeqLength)),
ysr@777 196
ysr@777 197 _pending_cards_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 198 _scanned_cards_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 199 _rs_lengths_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 200
johnc@1186 201 _pause_time_target_ms((double) MaxGCPauseMillis),
ysr@777 202
ysr@777 203 // </NEW PREDICTION>
ysr@777 204
ysr@777 205 _full_young_gcs(true),
ysr@777 206 _full_young_pause_num(0),
ysr@777 207 _partial_young_pause_num(0),
ysr@777 208
ysr@777 209 _during_marking(false),
ysr@777 210 _in_marking_window(false),
ysr@777 211 _in_marking_window_im(false),
ysr@777 212
ysr@777 213 _known_garbage_ratio(0.0),
ysr@777 214 _known_garbage_bytes(0),
ysr@777 215
ysr@777 216 _young_gc_eff_seq(new TruncatedSeq(TruncatedSeqLength)),
ysr@777 217
ysr@777 218 _recent_prev_end_times_for_all_gcs_sec(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 219
ysr@777 220 _recent_CS_bytes_used_before(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 221 _recent_CS_bytes_surviving(new TruncatedSeq(NumPrevPausesForHeuristics)),
ysr@777 222
ysr@777 223 _recent_avg_pause_time_ratio(0.0),
ysr@777 224 _num_markings(0),
ysr@777 225 _n_marks(0),
ysr@777 226 _n_pauses_at_mark_end(0),
ysr@777 227
ysr@777 228 _all_full_gc_times_ms(new NumberSeq()),
ysr@777 229
ysr@777 230 // G1PausesBtwnConcMark defaults to -1
ysr@777 231 // so the hack is to do the cast QQQ FIXME
ysr@777 232 _pauses_btwn_concurrent_mark((size_t)G1PausesBtwnConcMark),
ysr@777 233 _n_marks_since_last_pause(0),
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
apetrusenko@1826 297 const uint region_size = HeapRegion::GrainWords;
apetrusenko@1826 298 if (YoungPLABSize > region_size || OldPLABSize > region_size) {
apetrusenko@1826 299 char buffer[128];
apetrusenko@1826 300 jio_snprintf(buffer, sizeof(buffer), "%sPLABSize should be at most %u",
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];
ysr@777 323
ysr@777 324 // start conservatively
johnc@1186 325 _expensive_region_limit_ms = 0.5 * (double) MaxGCPauseMillis;
ysr@777 326
ysr@777 327 // <NEW PREDICTION>
ysr@777 328
ysr@777 329 int index;
ysr@777 330 if (ParallelGCThreads == 0)
ysr@777 331 index = 0;
ysr@777 332 else if (ParallelGCThreads > 8)
ysr@777 333 index = 7;
ysr@777 334 else
ysr@777 335 index = ParallelGCThreads - 1;
ysr@777 336
ysr@777 337 _pending_card_diff_seq->add(0.0);
ysr@777 338 _rs_length_diff_seq->add(rs_length_diff_defaults[index]);
ysr@777 339 _cost_per_card_ms_seq->add(cost_per_card_ms_defaults[index]);
ysr@777 340 _fully_young_cards_per_entry_ratio_seq->add(
ysr@777 341 fully_young_cards_per_entry_ratio_defaults[index]);
ysr@777 342 _cost_per_entry_ms_seq->add(cost_per_entry_ms_defaults[index]);
ysr@777 343 _cost_per_byte_ms_seq->add(cost_per_byte_ms_defaults[index]);
ysr@777 344 _constant_other_time_ms_seq->add(constant_other_time_ms_defaults[index]);
ysr@777 345 _young_other_cost_per_region_ms_seq->add(
ysr@777 346 young_other_cost_per_region_ms_defaults[index]);
ysr@777 347 _non_young_other_cost_per_region_ms_seq->add(
ysr@777 348 non_young_other_cost_per_region_ms_defaults[index]);
ysr@777 349
ysr@777 350 // </NEW PREDICTION>
ysr@777 351
tonyp@1965 352 // Below, we might need to calculate the pause time target based on
tonyp@1965 353 // the pause interval. When we do so we are going to give G1 maximum
tonyp@1965 354 // flexibility and allow it to do pauses when it needs to. So, we'll
tonyp@1965 355 // arrange that the pause interval to be pause time target + 1 to
tonyp@1965 356 // ensure that a) the pause time target is maximized with respect to
tonyp@1965 357 // the pause interval and b) we maintain the invariant that pause
tonyp@1965 358 // time target < pause interval. If the user does not want this
tonyp@1965 359 // maximum flexibility, they will have to set the pause interval
tonyp@1965 360 // explicitly.
tonyp@1965 361
tonyp@1965 362 // First make sure that, if either parameter is set, its value is
tonyp@1965 363 // reasonable.
tonyp@1965 364 if (!FLAG_IS_DEFAULT(MaxGCPauseMillis)) {
tonyp@1965 365 if (MaxGCPauseMillis < 1) {
tonyp@1965 366 vm_exit_during_initialization("MaxGCPauseMillis should be "
tonyp@1965 367 "greater than 0");
tonyp@1965 368 }
tonyp@1965 369 }
tonyp@1965 370 if (!FLAG_IS_DEFAULT(GCPauseIntervalMillis)) {
tonyp@1965 371 if (GCPauseIntervalMillis < 1) {
tonyp@1965 372 vm_exit_during_initialization("GCPauseIntervalMillis should be "
tonyp@1965 373 "greater than 0");
tonyp@1965 374 }
tonyp@1965 375 }
tonyp@1965 376
tonyp@1965 377 // Then, if the pause time target parameter was not set, set it to
tonyp@1965 378 // the default value.
tonyp@1965 379 if (FLAG_IS_DEFAULT(MaxGCPauseMillis)) {
tonyp@1965 380 if (FLAG_IS_DEFAULT(GCPauseIntervalMillis)) {
tonyp@1965 381 // The default pause time target in G1 is 200ms
tonyp@1965 382 FLAG_SET_DEFAULT(MaxGCPauseMillis, 200);
tonyp@1965 383 } else {
tonyp@1965 384 // We do not allow the pause interval to be set without the
tonyp@1965 385 // pause time target
tonyp@1965 386 vm_exit_during_initialization("GCPauseIntervalMillis cannot be set "
tonyp@1965 387 "without setting MaxGCPauseMillis");
tonyp@1965 388 }
tonyp@1965 389 }
tonyp@1965 390
tonyp@1965 391 // Then, if the interval parameter was not set, set it according to
tonyp@1965 392 // the pause time target (this will also deal with the case when the
tonyp@1965 393 // pause time target is the default value).
tonyp@1965 394 if (FLAG_IS_DEFAULT(GCPauseIntervalMillis)) {
tonyp@1965 395 FLAG_SET_DEFAULT(GCPauseIntervalMillis, MaxGCPauseMillis + 1);
tonyp@1965 396 }
tonyp@1965 397
tonyp@1965 398 // Finally, make sure that the two parameters are consistent.
tonyp@1965 399 if (MaxGCPauseMillis >= GCPauseIntervalMillis) {
tonyp@1965 400 char buffer[256];
tonyp@1965 401 jio_snprintf(buffer, 256,
tonyp@1965 402 "MaxGCPauseMillis (%u) should be less than "
tonyp@1965 403 "GCPauseIntervalMillis (%u)",
tonyp@1965 404 MaxGCPauseMillis, GCPauseIntervalMillis);
tonyp@1965 405 vm_exit_during_initialization(buffer);
tonyp@1965 406 }
tonyp@1965 407
tonyp@1965 408 double max_gc_time = (double) MaxGCPauseMillis / 1000.0;
johnc@1186 409 double time_slice = (double) GCPauseIntervalMillis / 1000.0;
ysr@777 410 _mmu_tracker = new G1MMUTrackerQueue(time_slice, max_gc_time);
johnc@1186 411 _sigma = (double) G1ConfidencePercent / 100.0;
ysr@777 412
ysr@777 413 // start conservatively (around 50ms is about right)
ysr@777 414 _concurrent_mark_remark_times_ms->add(0.05);
ysr@777 415 _concurrent_mark_cleanup_times_ms->add(0.20);
ysr@777 416 _tenuring_threshold = MaxTenuringThreshold;
tonyp@3066 417 // _max_survivor_regions will be calculated by
tonyp@3119 418 // update_young_list_target_length() during initialization.
tonyp@3066 419 _max_survivor_regions = 0;
apetrusenko@980 420
tonyp@1791 421 assert(GCTimeRatio > 0,
tonyp@1791 422 "we should have set it to a default value set_g1_gc_flags() "
tonyp@1791 423 "if a user set it to 0");
tonyp@1791 424 _gc_overhead_perc = 100.0 * (1.0 / (1.0 + GCTimeRatio));
tonyp@1791 425
tonyp@3119 426 uintx reserve_perc = G1ReservePercent;
tonyp@3119 427 // Put an artificial ceiling on this so that it's not set to a silly value.
tonyp@3119 428 if (reserve_perc > 50) {
tonyp@3119 429 reserve_perc = 50;
tonyp@3119 430 warning("G1ReservePercent is set to a value that is too large, "
tonyp@3119 431 "it's been updated to %u", reserve_perc);
tonyp@3119 432 }
tonyp@3119 433 _reserve_factor = (double) reserve_perc / 100.0;
brutisso@3120 434 // This will be set when the heap is expanded
tonyp@3119 435 // for the first time during initialization.
tonyp@3119 436 _reserve_regions = 0;
tonyp@3119 437
ysr@777 438 initialize_all();
ysr@777 439 }
ysr@777 440
ysr@777 441 // Increment "i", mod "len"
ysr@777 442 static void inc_mod(int& i, int len) {
ysr@777 443 i++; if (i == len) i = 0;
ysr@777 444 }
ysr@777 445
ysr@777 446 void G1CollectorPolicy::initialize_flags() {
ysr@777 447 set_min_alignment(HeapRegion::GrainBytes);
ysr@777 448 set_max_alignment(GenRemSet::max_alignment_constraint(rem_set_name()));
apetrusenko@982 449 if (SurvivorRatio < 1) {
apetrusenko@982 450 vm_exit_during_initialization("Invalid survivor ratio specified");
apetrusenko@982 451 }
ysr@777 452 CollectorPolicy::initialize_flags();
ysr@777 453 }
ysr@777 454
tonyp@1720 455 // The easiest way to deal with the parsing of the NewSize /
tonyp@1720 456 // MaxNewSize / etc. parameteres is to re-use the code in the
tonyp@1720 457 // TwoGenerationCollectorPolicy class. This is similar to what
tonyp@1720 458 // ParallelScavenge does with its GenerationSizer class (see
tonyp@1720 459 // ParallelScavengeHeap::initialize()). We might change this in the
tonyp@1720 460 // future, but it's a good start.
tonyp@1720 461 class G1YoungGenSizer : public TwoGenerationCollectorPolicy {
tonyp@1720 462
tonyp@1720 463 public:
tonyp@1720 464 G1YoungGenSizer() {
tonyp@1720 465 initialize_flags();
tonyp@1720 466 initialize_size_info();
tonyp@1720 467 }
brutisso@3120 468 size_t size_to_region_num(size_t byte_size) {
brutisso@3120 469 return MAX2((size_t) 1, byte_size / HeapRegion::GrainBytes);
brutisso@3120 470 }
tonyp@1720 471 size_t min_young_region_num() {
tonyp@1720 472 return size_to_region_num(_min_gen0_size);
tonyp@1720 473 }
tonyp@1720 474 size_t initial_young_region_num() {
tonyp@1720 475 return size_to_region_num(_initial_gen0_size);
tonyp@1720 476 }
tonyp@1720 477 size_t max_young_region_num() {
tonyp@1720 478 return size_to_region_num(_max_gen0_size);
tonyp@1720 479 }
tonyp@1720 480 };
tonyp@1720 481
brutisso@3120 482 void G1CollectorPolicy::update_young_list_size_using_newratio(size_t number_of_heap_regions) {
brutisso@3120 483 assert(number_of_heap_regions > 0, "Heap must be initialized");
brutisso@3120 484 size_t young_size = number_of_heap_regions / (NewRatio + 1);
brutisso@3120 485 _min_desired_young_length = young_size;
brutisso@3120 486 _max_desired_young_length = young_size;
brutisso@3120 487 }
brutisso@3120 488
ysr@777 489 void G1CollectorPolicy::init() {
ysr@777 490 // Set aside an initial future to_space.
ysr@777 491 _g1 = G1CollectedHeap::heap();
ysr@777 492
ysr@777 493 assert(Heap_lock->owned_by_self(), "Locking discipline.");
ysr@777 494
apetrusenko@980 495 initialize_gc_policy_counters();
apetrusenko@980 496
brutisso@3065 497 G1YoungGenSizer sizer;
brutisso@3065 498 size_t initial_region_num = sizer.initial_young_region_num();
brutisso@3120 499 _min_desired_young_length = sizer.min_young_region_num();
brutisso@3120 500 _max_desired_young_length = sizer.max_young_region_num();
brutisso@3120 501
brutisso@3120 502 if (FLAG_IS_CMDLINE(NewRatio)) {
brutisso@3120 503 if (FLAG_IS_CMDLINE(NewSize) || FLAG_IS_CMDLINE(MaxNewSize)) {
brutisso@3120 504 gclog_or_tty->print_cr("-XX:NewSize and -XX:MaxNewSize overrides -XX:NewRatio");
brutisso@3120 505 } else {
brutisso@3120 506 // Treat NewRatio as a fixed size that is only recalculated when the heap size changes
brutisso@3120 507 size_t heap_regions = sizer.size_to_region_num(_g1->n_regions());
brutisso@3120 508 update_young_list_size_using_newratio(heap_regions);
brutisso@3120 509 _using_new_ratio_calculations = true;
brutisso@3120 510 }
brutisso@3120 511 }
brutisso@3120 512
brutisso@3120 513 // GenCollectorPolicy guarantees that min <= initial <= max.
brutisso@3120 514 // Asserting here just to state that we rely on this property.
brutisso@3120 515 assert(_min_desired_young_length <= _max_desired_young_length, "Invalid min/max young gen size values");
brutisso@3120 516 assert(initial_region_num <= _max_desired_young_length, "Initial young gen size too large");
brutisso@3120 517 assert(_min_desired_young_length <= initial_region_num, "Initial young gen size too small");
brutisso@3120 518
brutisso@3120 519 set_adaptive_young_list_length(_min_desired_young_length < _max_desired_young_length);
brutisso@3120 520 if (adaptive_young_list_length()) {
brutisso@3065 521 _young_list_fixed_length = 0;
johnc@1829 522 } else {
brutisso@3065 523 _young_list_fixed_length = initial_region_num;
ysr@777 524 }
brutisso@3065 525 _free_regions_at_end_of_collection = _g1->free_regions();
tonyp@3119 526 update_young_list_target_length();
brutisso@3120 527 _prev_eden_capacity = _young_list_target_length * HeapRegion::GrainBytes;
johnc@1829 528
johnc@1829 529 // We may immediately start allocating regions and placing them on the
johnc@1829 530 // collection set list. Initialize the per-collection set info
johnc@1829 531 start_incremental_cset_building();
ysr@777 532 }
ysr@777 533
apetrusenko@980 534 // Create the jstat counters for the policy.
tonyp@3119 535 void G1CollectorPolicy::initialize_gc_policy_counters() {
brutisso@3065 536 _gc_policy_counters = new GCPolicyCounters("GarbageFirst", 1, 3);
apetrusenko@980 537 }
apetrusenko@980 538
tonyp@3119 539 bool G1CollectorPolicy::predict_will_fit(size_t young_length,
tonyp@3119 540 double base_time_ms,
tonyp@3119 541 size_t base_free_regions,
tonyp@3119 542 double target_pause_time_ms) {
tonyp@3119 543 if (young_length >= base_free_regions) {
tonyp@3119 544 // end condition 1: not enough space for the young regions
tonyp@3119 545 return false;
ysr@777 546 }
tonyp@3119 547
tonyp@3119 548 double accum_surv_rate = accum_yg_surv_rate_pred((int)(young_length - 1));
tonyp@3119 549 size_t bytes_to_copy =
tonyp@3119 550 (size_t) (accum_surv_rate * (double) HeapRegion::GrainBytes);
tonyp@3119 551 double copy_time_ms = predict_object_copy_time_ms(bytes_to_copy);
tonyp@3119 552 double young_other_time_ms = predict_young_other_time_ms(young_length);
tonyp@3119 553 double pause_time_ms = base_time_ms + copy_time_ms + young_other_time_ms;
tonyp@3119 554 if (pause_time_ms > target_pause_time_ms) {
tonyp@3119 555 // end condition 2: prediction is over the target pause time
tonyp@3119 556 return false;
tonyp@3119 557 }
tonyp@3119 558
tonyp@3119 559 size_t free_bytes =
tonyp@3119 560 (base_free_regions - young_length) * HeapRegion::GrainBytes;
tonyp@3119 561 if ((2.0 * sigma()) * (double) bytes_to_copy > (double) free_bytes) {
tonyp@3119 562 // end condition 3: out-of-space (conservatively!)
tonyp@3119 563 return false;
tonyp@3119 564 }
tonyp@3119 565
tonyp@3119 566 // success!
tonyp@3119 567 return true;
ysr@777 568 }
ysr@777 569
brutisso@3120 570 void G1CollectorPolicy::record_new_heap_size(size_t new_number_of_regions) {
brutisso@3120 571 // re-calculate the necessary reserve
brutisso@3120 572 double reserve_regions_d = (double) new_number_of_regions * _reserve_factor;
tonyp@3119 573 // We use ceiling so that if reserve_regions_d is > 0.0 (but
tonyp@3119 574 // smaller than 1.0) we'll get 1.
tonyp@3119 575 _reserve_regions = (size_t) ceil(reserve_regions_d);
brutisso@3120 576
brutisso@3120 577 if (_using_new_ratio_calculations) {
brutisso@3120 578 // -XX:NewRatio was specified so we need to update the
brutisso@3120 579 // young gen length when the heap size has changed.
brutisso@3120 580 update_young_list_size_using_newratio(new_number_of_regions);
brutisso@3120 581 }
tonyp@3119 582 }
tonyp@3119 583
tonyp@3119 584 size_t G1CollectorPolicy::calculate_young_list_desired_min_length(
tonyp@3119 585 size_t base_min_length) {
tonyp@3119 586 size_t desired_min_length = 0;
ysr@777 587 if (adaptive_young_list_length()) {
tonyp@3119 588 if (_alloc_rate_ms_seq->num() > 3) {
tonyp@3119 589 double now_sec = os::elapsedTime();
tonyp@3119 590 double when_ms = _mmu_tracker->when_max_gc_sec(now_sec) * 1000.0;
tonyp@3119 591 double alloc_rate_ms = predict_alloc_rate_ms();
tonyp@3119 592 desired_min_length = (size_t) ceil(alloc_rate_ms * when_ms);
tonyp@3119 593 } else {
tonyp@3119 594 // otherwise we don't have enough info to make the prediction
tonyp@3119 595 }
ysr@777 596 }
brutisso@3120 597 desired_min_length += base_min_length;
brutisso@3120 598 // make sure we don't go below any user-defined minimum bound
brutisso@3120 599 return MAX2(_min_desired_young_length, desired_min_length);
ysr@777 600 }
ysr@777 601
tonyp@3119 602 size_t G1CollectorPolicy::calculate_young_list_desired_max_length() {
tonyp@3119 603 // Here, we might want to also take into account any additional
tonyp@3119 604 // constraints (i.e., user-defined minimum bound). Currently, we
tonyp@3119 605 // effectively don't set this bound.
brutisso@3120 606 return _max_desired_young_length;
tonyp@3119 607 }
tonyp@3119 608
tonyp@3119 609 void G1CollectorPolicy::update_young_list_target_length(size_t rs_lengths) {
tonyp@3119 610 if (rs_lengths == (size_t) -1) {
tonyp@3119 611 // if it's set to the default value (-1), we should predict it;
tonyp@3119 612 // otherwise, use the given value.
tonyp@3119 613 rs_lengths = (size_t) get_new_prediction(_rs_lengths_seq);
tonyp@3119 614 }
tonyp@3119 615
tonyp@3119 616 // Calculate the absolute and desired min bounds.
tonyp@3119 617
tonyp@3119 618 // This is how many young regions we already have (currently: the survivors).
tonyp@3119 619 size_t base_min_length = recorded_survivor_regions();
tonyp@3119 620 // This is the absolute minimum young length, which ensures that we
tonyp@3119 621 // can allocate one eden region in the worst-case.
tonyp@3119 622 size_t absolute_min_length = base_min_length + 1;
tonyp@3119 623 size_t desired_min_length =
tonyp@3119 624 calculate_young_list_desired_min_length(base_min_length);
tonyp@3119 625 if (desired_min_length < absolute_min_length) {
tonyp@3119 626 desired_min_length = absolute_min_length;
tonyp@3119 627 }
tonyp@3119 628
tonyp@3119 629 // Calculate the absolute and desired max bounds.
tonyp@3119 630
tonyp@3119 631 // We will try our best not to "eat" into the reserve.
tonyp@3119 632 size_t absolute_max_length = 0;
tonyp@3119 633 if (_free_regions_at_end_of_collection > _reserve_regions) {
tonyp@3119 634 absolute_max_length = _free_regions_at_end_of_collection - _reserve_regions;
tonyp@3119 635 }
tonyp@3119 636 size_t desired_max_length = calculate_young_list_desired_max_length();
tonyp@3119 637 if (desired_max_length > absolute_max_length) {
tonyp@3119 638 desired_max_length = absolute_max_length;
tonyp@3119 639 }
tonyp@3119 640
tonyp@3119 641 size_t young_list_target_length = 0;
tonyp@3119 642 if (adaptive_young_list_length()) {
tonyp@3119 643 if (full_young_gcs()) {
tonyp@3119 644 young_list_target_length =
tonyp@3119 645 calculate_young_list_target_length(rs_lengths,
tonyp@3119 646 base_min_length,
tonyp@3119 647 desired_min_length,
tonyp@3119 648 desired_max_length);
tonyp@3119 649 _rs_lengths_prediction = rs_lengths;
tonyp@3119 650 } else {
tonyp@3119 651 // Don't calculate anything and let the code below bound it to
tonyp@3119 652 // the desired_min_length, i.e., do the next GC as soon as
tonyp@3119 653 // possible to maximize how many old regions we can add to it.
ysr@777 654 }
ysr@777 655 } else {
tonyp@3119 656 if (full_young_gcs()) {
tonyp@3119 657 young_list_target_length = _young_list_fixed_length;
tonyp@3119 658 } else {
tonyp@3119 659 // A bit arbitrary: during partially-young GCs we allocate half
tonyp@3119 660 // the young regions to try to add old regions to the CSet.
tonyp@3119 661 young_list_target_length = _young_list_fixed_length / 2;
tonyp@3119 662 // We choose to accept that we might go under the desired min
tonyp@3119 663 // length given that we intentionally ask for a smaller young gen.
tonyp@3119 664 desired_min_length = absolute_min_length;
tonyp@3119 665 }
ysr@777 666 }
ysr@777 667
tonyp@3119 668 // Make sure we don't go over the desired max length, nor under the
tonyp@3119 669 // desired min length. In case they clash, desired_min_length wins
tonyp@3119 670 // which is why that test is second.
tonyp@3119 671 if (young_list_target_length > desired_max_length) {
tonyp@3119 672 young_list_target_length = desired_max_length;
tonyp@3119 673 }
tonyp@3119 674 if (young_list_target_length < desired_min_length) {
tonyp@3119 675 young_list_target_length = desired_min_length;
tonyp@3119 676 }
tonyp@3119 677
tonyp@3119 678 assert(young_list_target_length > recorded_survivor_regions(),
tonyp@3119 679 "we should be able to allocate at least one eden region");
tonyp@3119 680 assert(young_list_target_length >= absolute_min_length, "post-condition");
tonyp@3119 681 _young_list_target_length = young_list_target_length;
tonyp@3119 682
tonyp@3119 683 update_max_gc_locker_expansion();
ysr@777 684 }
ysr@777 685
tonyp@3119 686 size_t
tonyp@3119 687 G1CollectorPolicy::calculate_young_list_target_length(size_t rs_lengths,
tonyp@3119 688 size_t base_min_length,
tonyp@3119 689 size_t desired_min_length,
tonyp@3119 690 size_t desired_max_length) {
tonyp@3119 691 assert(adaptive_young_list_length(), "pre-condition");
tonyp@3119 692 assert(full_young_gcs(), "only call this for fully-young GCs");
tonyp@3119 693
tonyp@3119 694 // In case some edge-condition makes the desired max length too small...
tonyp@3119 695 if (desired_max_length <= desired_min_length) {
tonyp@3119 696 return desired_min_length;
tonyp@3119 697 }
tonyp@3119 698
tonyp@3119 699 // We'll adjust min_young_length and max_young_length not to include
tonyp@3119 700 // the already allocated young regions (i.e., so they reflect the
tonyp@3119 701 // min and max eden regions we'll allocate). The base_min_length
tonyp@3119 702 // will be reflected in the predictions by the
tonyp@3119 703 // survivor_regions_evac_time prediction.
tonyp@3119 704 assert(desired_min_length > base_min_length, "invariant");
tonyp@3119 705 size_t min_young_length = desired_min_length - base_min_length;
tonyp@3119 706 assert(desired_max_length > base_min_length, "invariant");
tonyp@3119 707 size_t max_young_length = desired_max_length - base_min_length;
tonyp@3119 708
tonyp@3119 709 double target_pause_time_ms = _mmu_tracker->max_gc_time() * 1000.0;
tonyp@3119 710 double survivor_regions_evac_time = predict_survivor_regions_evac_time();
tonyp@3119 711 size_t pending_cards = (size_t) get_new_prediction(_pending_cards_seq);
tonyp@3119 712 size_t adj_rs_lengths = rs_lengths + predict_rs_length_diff();
tonyp@3119 713 size_t scanned_cards = predict_young_card_num(adj_rs_lengths);
tonyp@3119 714 double base_time_ms =
tonyp@3119 715 predict_base_elapsed_time_ms(pending_cards, scanned_cards) +
tonyp@3119 716 survivor_regions_evac_time;
tonyp@3119 717 size_t available_free_regions = _free_regions_at_end_of_collection;
tonyp@3119 718 size_t base_free_regions = 0;
tonyp@3119 719 if (available_free_regions > _reserve_regions) {
tonyp@3119 720 base_free_regions = available_free_regions - _reserve_regions;
tonyp@3119 721 }
tonyp@3119 722
tonyp@3119 723 // Here, we will make sure that the shortest young length that
tonyp@3119 724 // makes sense fits within the target pause time.
tonyp@3119 725
tonyp@3119 726 if (predict_will_fit(min_young_length, base_time_ms,
tonyp@3119 727 base_free_regions, target_pause_time_ms)) {
tonyp@3119 728 // The shortest young length will fit into the target pause time;
tonyp@3119 729 // we'll now check whether the absolute maximum number of young
tonyp@3119 730 // regions will fit in the target pause time. If not, we'll do
tonyp@3119 731 // a binary search between min_young_length and max_young_length.
tonyp@3119 732 if (predict_will_fit(max_young_length, base_time_ms,
tonyp@3119 733 base_free_regions, target_pause_time_ms)) {
tonyp@3119 734 // The maximum young length will fit into the target pause time.
tonyp@3119 735 // We are done so set min young length to the maximum length (as
tonyp@3119 736 // the result is assumed to be returned in min_young_length).
tonyp@3119 737 min_young_length = max_young_length;
tonyp@3119 738 } else {
tonyp@3119 739 // The maximum possible number of young regions will not fit within
tonyp@3119 740 // the target pause time so we'll search for the optimal
tonyp@3119 741 // length. The loop invariants are:
tonyp@3119 742 //
tonyp@3119 743 // min_young_length < max_young_length
tonyp@3119 744 // min_young_length is known to fit into the target pause time
tonyp@3119 745 // max_young_length is known not to fit into the target pause time
tonyp@3119 746 //
tonyp@3119 747 // Going into the loop we know the above hold as we've just
tonyp@3119 748 // checked them. Every time around the loop we check whether
tonyp@3119 749 // the middle value between min_young_length and
tonyp@3119 750 // max_young_length fits into the target pause time. If it
tonyp@3119 751 // does, it becomes the new min. If it doesn't, it becomes
tonyp@3119 752 // the new max. This way we maintain the loop invariants.
tonyp@3119 753
tonyp@3119 754 assert(min_young_length < max_young_length, "invariant");
tonyp@3119 755 size_t diff = (max_young_length - min_young_length) / 2;
tonyp@3119 756 while (diff > 0) {
tonyp@3119 757 size_t young_length = min_young_length + diff;
tonyp@3119 758 if (predict_will_fit(young_length, base_time_ms,
tonyp@3119 759 base_free_regions, target_pause_time_ms)) {
tonyp@3119 760 min_young_length = young_length;
tonyp@3119 761 } else {
tonyp@3119 762 max_young_length = young_length;
tonyp@3119 763 }
tonyp@3119 764 assert(min_young_length < max_young_length, "invariant");
tonyp@3119 765 diff = (max_young_length - min_young_length) / 2;
tonyp@3119 766 }
tonyp@3119 767 // The results is min_young_length which, according to the
tonyp@3119 768 // loop invariants, should fit within the target pause time.
tonyp@3119 769
tonyp@3119 770 // These are the post-conditions of the binary search above:
tonyp@3119 771 assert(min_young_length < max_young_length,
tonyp@3119 772 "otherwise we should have discovered that max_young_length "
tonyp@3119 773 "fits into the pause target and not done the binary search");
tonyp@3119 774 assert(predict_will_fit(min_young_length, base_time_ms,
tonyp@3119 775 base_free_regions, target_pause_time_ms),
tonyp@3119 776 "min_young_length, the result of the binary search, should "
tonyp@3119 777 "fit into the pause target");
tonyp@3119 778 assert(!predict_will_fit(min_young_length + 1, base_time_ms,
tonyp@3119 779 base_free_regions, target_pause_time_ms),
tonyp@3119 780 "min_young_length, the result of the binary search, should be "
tonyp@3119 781 "optimal, so no larger length should fit into the pause target");
tonyp@3119 782 }
tonyp@3119 783 } else {
tonyp@3119 784 // Even the minimum length doesn't fit into the pause time
tonyp@3119 785 // target, return it as the result nevertheless.
tonyp@3119 786 }
tonyp@3119 787 return base_min_length + min_young_length;
ysr@777 788 }
ysr@777 789
apetrusenko@980 790 double G1CollectorPolicy::predict_survivor_regions_evac_time() {
apetrusenko@980 791 double survivor_regions_evac_time = 0.0;
apetrusenko@980 792 for (HeapRegion * r = _recorded_survivor_head;
apetrusenko@980 793 r != NULL && r != _recorded_survivor_tail->get_next_young_region();
apetrusenko@980 794 r = r->get_next_young_region()) {
apetrusenko@980 795 survivor_regions_evac_time += predict_region_elapsed_time_ms(r, true);
apetrusenko@980 796 }
apetrusenko@980 797 return survivor_regions_evac_time;
apetrusenko@980 798 }
apetrusenko@980 799
tonyp@3119 800 void G1CollectorPolicy::revise_young_list_target_length_if_necessary() {
ysr@777 801 guarantee( adaptive_young_list_length(), "should not call this otherwise" );
ysr@777 802
johnc@1829 803 size_t rs_lengths = _g1->young_list()->sampled_rs_lengths();
ysr@777 804 if (rs_lengths > _rs_lengths_prediction) {
ysr@777 805 // add 10% to avoid having to recalculate often
ysr@777 806 size_t rs_lengths_prediction = rs_lengths * 1100 / 1000;
tonyp@3119 807 update_young_list_target_length(rs_lengths_prediction);
ysr@777 808 }
ysr@777 809 }
ysr@777 810
tonyp@3119 811
tonyp@3119 812
ysr@777 813 HeapWord* G1CollectorPolicy::mem_allocate_work(size_t size,
ysr@777 814 bool is_tlab,
ysr@777 815 bool* gc_overhead_limit_was_exceeded) {
ysr@777 816 guarantee(false, "Not using this policy feature yet.");
ysr@777 817 return NULL;
ysr@777 818 }
ysr@777 819
ysr@777 820 // This method controls how a collector handles one or more
ysr@777 821 // of its generations being fully allocated.
ysr@777 822 HeapWord* G1CollectorPolicy::satisfy_failed_allocation(size_t size,
ysr@777 823 bool is_tlab) {
ysr@777 824 guarantee(false, "Not using this policy feature yet.");
ysr@777 825 return NULL;
ysr@777 826 }
ysr@777 827
ysr@777 828
ysr@777 829 #ifndef PRODUCT
ysr@777 830 bool G1CollectorPolicy::verify_young_ages() {
johnc@1829 831 HeapRegion* head = _g1->young_list()->first_region();
ysr@777 832 return
ysr@777 833 verify_young_ages(head, _short_lived_surv_rate_group);
ysr@777 834 // also call verify_young_ages on any additional surv rate groups
ysr@777 835 }
ysr@777 836
ysr@777 837 bool
ysr@777 838 G1CollectorPolicy::verify_young_ages(HeapRegion* head,
ysr@777 839 SurvRateGroup *surv_rate_group) {
ysr@777 840 guarantee( surv_rate_group != NULL, "pre-condition" );
ysr@777 841
ysr@777 842 const char* name = surv_rate_group->name();
ysr@777 843 bool ret = true;
ysr@777 844 int prev_age = -1;
ysr@777 845
ysr@777 846 for (HeapRegion* curr = head;
ysr@777 847 curr != NULL;
ysr@777 848 curr = curr->get_next_young_region()) {
ysr@777 849 SurvRateGroup* group = curr->surv_rate_group();
ysr@777 850 if (group == NULL && !curr->is_survivor()) {
ysr@777 851 gclog_or_tty->print_cr("## %s: encountered NULL surv_rate_group", name);
ysr@777 852 ret = false;
ysr@777 853 }
ysr@777 854
ysr@777 855 if (surv_rate_group == group) {
ysr@777 856 int age = curr->age_in_surv_rate_group();
ysr@777 857
ysr@777 858 if (age < 0) {
ysr@777 859 gclog_or_tty->print_cr("## %s: encountered negative age", name);
ysr@777 860 ret = false;
ysr@777 861 }
ysr@777 862
ysr@777 863 if (age <= prev_age) {
ysr@777 864 gclog_or_tty->print_cr("## %s: region ages are not strictly increasing "
ysr@777 865 "(%d, %d)", name, age, prev_age);
ysr@777 866 ret = false;
ysr@777 867 }
ysr@777 868 prev_age = age;
ysr@777 869 }
ysr@777 870 }
ysr@777 871
ysr@777 872 return ret;
ysr@777 873 }
ysr@777 874 #endif // PRODUCT
ysr@777 875
ysr@777 876 void G1CollectorPolicy::record_full_collection_start() {
ysr@777 877 _cur_collection_start_sec = os::elapsedTime();
ysr@777 878 // Release the future to-space so that it is available for compaction into.
ysr@777 879 _g1->set_full_collection();
ysr@777 880 }
ysr@777 881
ysr@777 882 void G1CollectorPolicy::record_full_collection_end() {
ysr@777 883 // Consider this like a collection pause for the purposes of allocation
ysr@777 884 // since last pause.
ysr@777 885 double end_sec = os::elapsedTime();
ysr@777 886 double full_gc_time_sec = end_sec - _cur_collection_start_sec;
ysr@777 887 double full_gc_time_ms = full_gc_time_sec * 1000.0;
ysr@777 888
ysr@777 889 _all_full_gc_times_ms->add(full_gc_time_ms);
ysr@777 890
tonyp@1030 891 update_recent_gc_times(end_sec, full_gc_time_ms);
ysr@777 892
ysr@777 893 _g1->clear_full_collection();
ysr@777 894
ysr@777 895 // "Nuke" the heuristics that control the fully/partially young GC
ysr@777 896 // transitions and make sure we start with fully young GCs after the
ysr@777 897 // Full GC.
ysr@777 898 set_full_young_gcs(true);
ysr@777 899 _last_full_young_gc = false;
ysr@777 900 _should_revert_to_full_young_gcs = false;
tonyp@1794 901 clear_initiate_conc_mark_if_possible();
tonyp@1794 902 clear_during_initial_mark_pause();
ysr@777 903 _known_garbage_bytes = 0;
ysr@777 904 _known_garbage_ratio = 0.0;
ysr@777 905 _in_marking_window = false;
ysr@777 906 _in_marking_window_im = false;
ysr@777 907
ysr@777 908 _short_lived_surv_rate_group->start_adding_regions();
ysr@777 909 // also call this on any additional surv rate groups
ysr@777 910
apetrusenko@980 911 record_survivor_regions(0, NULL, NULL);
apetrusenko@980 912
ysr@777 913 _prev_region_num_young = _region_num_young;
ysr@777 914 _prev_region_num_tenured = _region_num_tenured;
ysr@777 915
ysr@777 916 _free_regions_at_end_of_collection = _g1->free_regions();
apetrusenko@980 917 // Reset survivors SurvRateGroup.
apetrusenko@980 918 _survivor_surv_rate_group->reset();
tonyp@3119 919 update_young_list_target_length();
tonyp@2315 920 }
ysr@777 921
ysr@777 922 void G1CollectorPolicy::record_stop_world_start() {
ysr@777 923 _stop_world_start = os::elapsedTime();
ysr@777 924 }
ysr@777 925
ysr@777 926 void G1CollectorPolicy::record_collection_pause_start(double start_time_sec,
ysr@777 927 size_t start_used) {
ysr@777 928 if (PrintGCDetails) {
ysr@777 929 gclog_or_tty->stamp(PrintGCTimeStamps);
ysr@777 930 gclog_or_tty->print("[GC pause");
brutisso@3065 931 gclog_or_tty->print(" (%s)", full_young_gcs() ? "young" : "partial");
ysr@777 932 }
ysr@777 933
tonyp@3119 934 // We only need to do this here as the policy will only be applied
tonyp@3119 935 // to the GC we're about to start. so, no point is calculating this
tonyp@3119 936 // every time we calculate / recalculate the target young length.
tonyp@3119 937 update_survivors_policy();
tonyp@3119 938
tonyp@2315 939 assert(_g1->used() == _g1->recalculate_used(),
tonyp@2315 940 err_msg("sanity, used: "SIZE_FORMAT" recalculate_used: "SIZE_FORMAT,
tonyp@2315 941 _g1->used(), _g1->recalculate_used()));
ysr@777 942
ysr@777 943 double s_w_t_ms = (start_time_sec - _stop_world_start) * 1000.0;
ysr@777 944 _all_stop_world_times_ms->add(s_w_t_ms);
ysr@777 945 _stop_world_start = 0.0;
ysr@777 946
ysr@777 947 _cur_collection_start_sec = start_time_sec;
ysr@777 948 _cur_collection_pause_used_at_start_bytes = start_used;
ysr@777 949 _cur_collection_pause_used_regions_at_start = _g1->used_regions();
ysr@777 950 _pending_cards = _g1->pending_card_num();
ysr@777 951 _max_pending_cards = _g1->max_pending_card_num();
ysr@777 952
ysr@777 953 _bytes_in_collection_set_before_gc = 0;
tonyp@3028 954 _bytes_copied_during_gc = 0;
ysr@777 955
tonyp@2961 956 YoungList* young_list = _g1->young_list();
tonyp@2961 957 _eden_bytes_before_gc = young_list->eden_used_bytes();
tonyp@2961 958 _survivor_bytes_before_gc = young_list->survivor_used_bytes();
tonyp@2961 959 _capacity_before_gc = _g1->capacity();
tonyp@2961 960
ysr@777 961 #ifdef DEBUG
ysr@777 962 // initialise these to something well known so that we can spot
ysr@777 963 // if they are not set properly
ysr@777 964
ysr@777 965 for (int i = 0; i < _parallel_gc_threads; ++i) {
tonyp@1966 966 _par_last_gc_worker_start_times_ms[i] = -1234.0;
tonyp@1966 967 _par_last_ext_root_scan_times_ms[i] = -1234.0;
tonyp@1966 968 _par_last_mark_stack_scan_times_ms[i] = -1234.0;
tonyp@1966 969 _par_last_update_rs_times_ms[i] = -1234.0;
tonyp@1966 970 _par_last_update_rs_processed_buffers[i] = -1234.0;
tonyp@1966 971 _par_last_scan_rs_times_ms[i] = -1234.0;
tonyp@1966 972 _par_last_obj_copy_times_ms[i] = -1234.0;
tonyp@1966 973 _par_last_termination_times_ms[i] = -1234.0;
tonyp@1966 974 _par_last_termination_attempts[i] = -1234.0;
tonyp@1966 975 _par_last_gc_worker_end_times_ms[i] = -1234.0;
brutisso@2712 976 _par_last_gc_worker_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
ysr@777 985 _satb_drain_time_set = false;
ysr@777 986 _last_satb_drain_processed_buffers = -1;
ysr@777 987
brutisso@3065 988 _last_young_gc_full = false;
ysr@777 989
ysr@777 990 // do that for any other surv rate groups
ysr@777 991 _short_lived_surv_rate_group->stop_adding_regions();
tonyp@1717 992 _survivors_age_table.clear();
apetrusenko@980 993
ysr@777 994 assert( verify_young_ages(), "region age verification" );
ysr@777 995 }
ysr@777 996
ysr@777 997 void G1CollectorPolicy::record_mark_closure_time(double mark_closure_time_ms) {
ysr@777 998 _mark_closure_time_ms = mark_closure_time_ms;
ysr@777 999 }
ysr@777 1000
brutisso@3065 1001 void G1CollectorPolicy::record_concurrent_mark_init_end(double
ysr@777 1002 mark_init_elapsed_time_ms) {
ysr@777 1003 _during_marking = true;
tonyp@1794 1004 assert(!initiate_conc_mark_if_possible(), "we should have cleared it by now");
tonyp@1794 1005 clear_during_initial_mark_pause();
ysr@777 1006 _cur_mark_stop_world_time_ms = mark_init_elapsed_time_ms;
ysr@777 1007 }
ysr@777 1008
ysr@777 1009 void G1CollectorPolicy::record_concurrent_mark_remark_start() {
ysr@777 1010 _mark_remark_start_sec = os::elapsedTime();
ysr@777 1011 _during_marking = false;
ysr@777 1012 }
ysr@777 1013
ysr@777 1014 void G1CollectorPolicy::record_concurrent_mark_remark_end() {
ysr@777 1015 double end_time_sec = os::elapsedTime();
ysr@777 1016 double elapsed_time_ms = (end_time_sec - _mark_remark_start_sec)*1000.0;
ysr@777 1017 _concurrent_mark_remark_times_ms->add(elapsed_time_ms);
ysr@777 1018 _cur_mark_stop_world_time_ms += elapsed_time_ms;
ysr@777 1019 _prev_collection_pause_end_ms += elapsed_time_ms;
ysr@777 1020
ysr@777 1021 _mmu_tracker->add_pause(_mark_remark_start_sec, end_time_sec, true);
ysr@777 1022 }
ysr@777 1023
ysr@777 1024 void G1CollectorPolicy::record_concurrent_mark_cleanup_start() {
ysr@777 1025 _mark_cleanup_start_sec = os::elapsedTime();
ysr@777 1026 }
ysr@777 1027
ysr@777 1028 void
ysr@777 1029 G1CollectorPolicy::record_concurrent_mark_cleanup_end(size_t freed_bytes,
ysr@777 1030 size_t max_live_bytes) {
ysr@777 1031 record_concurrent_mark_cleanup_end_work1(freed_bytes, max_live_bytes);
ysr@777 1032 record_concurrent_mark_cleanup_end_work2();
ysr@777 1033 }
ysr@777 1034
ysr@777 1035 void
ysr@777 1036 G1CollectorPolicy::
ysr@777 1037 record_concurrent_mark_cleanup_end_work1(size_t freed_bytes,
ysr@777 1038 size_t max_live_bytes) {
tonyp@3114 1039 if (_n_marks < 2) {
tonyp@3114 1040 _n_marks++;
tonyp@3114 1041 }
ysr@777 1042 }
ysr@777 1043
ysr@777 1044 // The important thing about this is that it includes "os::elapsedTime".
ysr@777 1045 void G1CollectorPolicy::record_concurrent_mark_cleanup_end_work2() {
ysr@777 1046 double end_time_sec = os::elapsedTime();
ysr@777 1047 double elapsed_time_ms = (end_time_sec - _mark_cleanup_start_sec)*1000.0;
ysr@777 1048 _concurrent_mark_cleanup_times_ms->add(elapsed_time_ms);
ysr@777 1049 _cur_mark_stop_world_time_ms += elapsed_time_ms;
ysr@777 1050 _prev_collection_pause_end_ms += elapsed_time_ms;
ysr@777 1051
ysr@777 1052 _mmu_tracker->add_pause(_mark_cleanup_start_sec, end_time_sec, true);
ysr@777 1053
ysr@777 1054 _num_markings++;
ysr@777 1055 _n_pauses_at_mark_end = _n_pauses;
ysr@777 1056 _n_marks_since_last_pause++;
ysr@777 1057 }
ysr@777 1058
ysr@777 1059 void
ysr@777 1060 G1CollectorPolicy::record_concurrent_mark_cleanup_completed() {
brutisso@3065 1061 _should_revert_to_full_young_gcs = false;
brutisso@3065 1062 _last_full_young_gc = true;
brutisso@3065 1063 _in_marking_window = false;
ysr@777 1064 }
ysr@777 1065
ysr@777 1066 void G1CollectorPolicy::record_concurrent_pause() {
ysr@777 1067 if (_stop_world_start > 0.0) {
ysr@777 1068 double yield_ms = (os::elapsedTime() - _stop_world_start) * 1000.0;
ysr@777 1069 _all_yield_times_ms->add(yield_ms);
ysr@777 1070 }
ysr@777 1071 }
ysr@777 1072
ysr@777 1073 void G1CollectorPolicy::record_concurrent_pause_end() {
ysr@777 1074 }
ysr@777 1075
ysr@777 1076 template<class T>
ysr@777 1077 T sum_of(T* sum_arr, int start, int n, int N) {
ysr@777 1078 T sum = (T)0;
ysr@777 1079 for (int i = 0; i < n; i++) {
ysr@777 1080 int j = (start + i) % N;
ysr@777 1081 sum += sum_arr[j];
ysr@777 1082 }
ysr@777 1083 return sum;
ysr@777 1084 }
ysr@777 1085
tonyp@1966 1086 void G1CollectorPolicy::print_par_stats(int level,
tonyp@1966 1087 const char* str,
brutisso@2712 1088 double* data) {
ysr@777 1089 double min = data[0], max = data[0];
ysr@777 1090 double total = 0.0;
brutisso@2645 1091 LineBuffer buf(level);
brutisso@2645 1092 buf.append("[%s (ms):", str);
ysr@777 1093 for (uint i = 0; i < ParallelGCThreads; ++i) {
ysr@777 1094 double val = data[i];
ysr@777 1095 if (val < min)
ysr@777 1096 min = val;
ysr@777 1097 if (val > max)
ysr@777 1098 max = val;
ysr@777 1099 total += val;
brutisso@2645 1100 buf.append(" %3.1lf", val);
ysr@777 1101 }
brutisso@2712 1102 buf.append_and_print_cr("");
brutisso@2712 1103 double avg = total / (double) ParallelGCThreads;
brutisso@2712 1104 buf.append_and_print_cr(" Avg: %5.1lf, Min: %5.1lf, Max: %5.1lf, Diff: %5.1lf]",
brutisso@2712 1105 avg, min, max, max - min);
ysr@777 1106 }
ysr@777 1107
tonyp@1966 1108 void G1CollectorPolicy::print_par_sizes(int level,
tonyp@1966 1109 const char* str,
brutisso@2712 1110 double* data) {
ysr@777 1111 double min = data[0], max = data[0];
ysr@777 1112 double total = 0.0;
brutisso@2645 1113 LineBuffer buf(level);
brutisso@2645 1114 buf.append("[%s :", str);
ysr@777 1115 for (uint i = 0; i < ParallelGCThreads; ++i) {
ysr@777 1116 double val = data[i];
ysr@777 1117 if (val < min)
ysr@777 1118 min = val;
ysr@777 1119 if (val > max)
ysr@777 1120 max = val;
ysr@777 1121 total += val;
brutisso@2645 1122 buf.append(" %d", (int) val);
ysr@777 1123 }
brutisso@2712 1124 buf.append_and_print_cr("");
brutisso@2712 1125 double avg = total / (double) ParallelGCThreads;
brutisso@2712 1126 buf.append_and_print_cr(" Sum: %d, Avg: %d, Min: %d, Max: %d, Diff: %d]",
brutisso@2712 1127 (int)total, (int)avg, (int)min, (int)max, (int)max - (int)min);
ysr@777 1128 }
ysr@777 1129
ysr@777 1130 void G1CollectorPolicy::print_stats (int level,
ysr@777 1131 const char* str,
ysr@777 1132 double value) {
brutisso@2645 1133 LineBuffer(level).append_and_print_cr("[%s: %5.1lf ms]", str, value);
ysr@777 1134 }
ysr@777 1135
ysr@777 1136 void G1CollectorPolicy::print_stats (int level,
ysr@777 1137 const char* str,
ysr@777 1138 int value) {
brutisso@2645 1139 LineBuffer(level).append_and_print_cr("[%s: %d]", str, value);
ysr@777 1140 }
ysr@777 1141
ysr@777 1142 double G1CollectorPolicy::avg_value (double* data) {
jmasa@2188 1143 if (G1CollectedHeap::use_parallel_gc_threads()) {
ysr@777 1144 double ret = 0.0;
ysr@777 1145 for (uint i = 0; i < ParallelGCThreads; ++i)
ysr@777 1146 ret += data[i];
ysr@777 1147 return ret / (double) ParallelGCThreads;
ysr@777 1148 } else {
ysr@777 1149 return data[0];
ysr@777 1150 }
ysr@777 1151 }
ysr@777 1152
ysr@777 1153 double G1CollectorPolicy::max_value (double* data) {
jmasa@2188 1154 if (G1CollectedHeap::use_parallel_gc_threads()) {
ysr@777 1155 double ret = data[0];
ysr@777 1156 for (uint i = 1; i < ParallelGCThreads; ++i)
ysr@777 1157 if (data[i] > ret)
ysr@777 1158 ret = data[i];
ysr@777 1159 return ret;
ysr@777 1160 } else {
ysr@777 1161 return data[0];
ysr@777 1162 }
ysr@777 1163 }
ysr@777 1164
ysr@777 1165 double G1CollectorPolicy::sum_of_values (double* data) {
jmasa@2188 1166 if (G1CollectedHeap::use_parallel_gc_threads()) {
ysr@777 1167 double sum = 0.0;
ysr@777 1168 for (uint i = 0; i < ParallelGCThreads; i++)
ysr@777 1169 sum += data[i];
ysr@777 1170 return sum;
ysr@777 1171 } else {
ysr@777 1172 return data[0];
ysr@777 1173 }
ysr@777 1174 }
ysr@777 1175
ysr@777 1176 double G1CollectorPolicy::max_sum (double* data1,
ysr@777 1177 double* data2) {
ysr@777 1178 double ret = data1[0] + data2[0];
ysr@777 1179
jmasa@2188 1180 if (G1CollectedHeap::use_parallel_gc_threads()) {
ysr@777 1181 for (uint i = 1; i < ParallelGCThreads; ++i) {
ysr@777 1182 double data = data1[i] + data2[i];
ysr@777 1183 if (data > ret)
ysr@777 1184 ret = data;
ysr@777 1185 }
ysr@777 1186 }
ysr@777 1187 return ret;
ysr@777 1188 }
ysr@777 1189
ysr@777 1190 // Anything below that is considered to be zero
ysr@777 1191 #define MIN_TIMER_GRANULARITY 0.0000001
ysr@777 1192
tonyp@2062 1193 void G1CollectorPolicy::record_collection_pause_end() {
ysr@777 1194 double end_time_sec = os::elapsedTime();
ysr@777 1195 double elapsed_ms = _last_pause_time_ms;
jmasa@2188 1196 bool parallel = G1CollectedHeap::use_parallel_gc_threads();
ysr@777 1197 size_t rs_size =
ysr@777 1198 _cur_collection_pause_used_regions_at_start - collection_set_size();
ysr@777 1199 size_t cur_used_bytes = _g1->used();
ysr@777 1200 assert(cur_used_bytes == _g1->recalculate_used(), "It should!");
ysr@777 1201 bool last_pause_included_initial_mark = false;
tonyp@2062 1202 bool update_stats = !_g1->evacuation_failed();
ysr@777 1203
ysr@777 1204 #ifndef PRODUCT
ysr@777 1205 if (G1YoungSurvRateVerbose) {
ysr@777 1206 gclog_or_tty->print_cr("");
ysr@777 1207 _short_lived_surv_rate_group->print();
ysr@777 1208 // do that for any other surv rate groups too
ysr@777 1209 }
ysr@777 1210 #endif // PRODUCT
ysr@777 1211
brutisso@3065 1212 last_pause_included_initial_mark = during_initial_mark_pause();
brutisso@3065 1213 if (last_pause_included_initial_mark)
brutisso@3065 1214 record_concurrent_mark_init_end(0.0);
brutisso@3065 1215
tonyp@3114 1216 size_t marking_initiating_used_threshold =
brutisso@3065 1217 (_g1->capacity() / 100) * InitiatingHeapOccupancyPercent;
brutisso@3065 1218
brutisso@3065 1219 if (!_g1->mark_in_progress() && !_last_full_young_gc) {
brutisso@3065 1220 assert(!last_pause_included_initial_mark, "invariant");
tonyp@3114 1221 if (cur_used_bytes > marking_initiating_used_threshold) {
tonyp@3114 1222 if (cur_used_bytes > _prev_collection_pause_used_at_end_bytes) {
tonyp@1794 1223 assert(!during_initial_mark_pause(), "we should not see this here");
tonyp@1794 1224
tonyp@3114 1225 ergo_verbose3(ErgoConcCycles,
tonyp@3114 1226 "request concurrent cycle initiation",
tonyp@3114 1227 ergo_format_reason("occupancy higher than threshold")
tonyp@3114 1228 ergo_format_byte("occupancy")
tonyp@3114 1229 ergo_format_byte_perc("threshold"),
tonyp@3114 1230 cur_used_bytes,
tonyp@3114 1231 marking_initiating_used_threshold,
tonyp@3114 1232 (double) InitiatingHeapOccupancyPercent);
tonyp@3114 1233
tonyp@1794 1234 // Note: this might have already been set, if during the last
tonyp@1794 1235 // pause we decided to start a cycle but at the beginning of
tonyp@1794 1236 // this pause we decided to postpone it. That's OK.
tonyp@1794 1237 set_initiate_conc_mark_if_possible();
tonyp@3114 1238 } else {
tonyp@3114 1239 ergo_verbose2(ErgoConcCycles,
tonyp@3114 1240 "do not request concurrent cycle initiation",
tonyp@3114 1241 ergo_format_reason("occupancy lower than previous occupancy")
tonyp@3114 1242 ergo_format_byte("occupancy")
tonyp@3114 1243 ergo_format_byte("previous occupancy"),
tonyp@3114 1244 cur_used_bytes,
tonyp@3114 1245 _prev_collection_pause_used_at_end_bytes);
tonyp@3114 1246 }
ysr@777 1247 }
ysr@777 1248 }
ysr@777 1249
brutisso@3065 1250 _prev_collection_pause_used_at_end_bytes = cur_used_bytes;
brutisso@3065 1251
ysr@777 1252 _mmu_tracker->add_pause(end_time_sec - elapsed_ms/1000.0,
ysr@777 1253 end_time_sec, false);
ysr@777 1254
ysr@777 1255 guarantee(_cur_collection_pause_used_regions_at_start >=
ysr@777 1256 collection_set_size(),
ysr@777 1257 "Negative RS size?");
ysr@777 1258
ysr@777 1259 // This assert is exempted when we're doing parallel collection pauses,
ysr@777 1260 // because the fragmentation caused by the parallel GC allocation buffers
ysr@777 1261 // can lead to more memory being used during collection than was used
ysr@777 1262 // before. Best leave this out until the fragmentation problem is fixed.
ysr@777 1263 // Pauses in which evacuation failed can also lead to negative
ysr@777 1264 // collections, since no space is reclaimed from a region containing an
ysr@777 1265 // object whose evacuation failed.
ysr@777 1266 // Further, we're now always doing parallel collection. But I'm still
ysr@777 1267 // leaving this here as a placeholder for a more precise assertion later.
ysr@777 1268 // (DLD, 10/05.)
ysr@777 1269 assert((true || parallel) // Always using GC LABs now.
ysr@777 1270 || _g1->evacuation_failed()
ysr@777 1271 || _cur_collection_pause_used_at_start_bytes >= cur_used_bytes,
ysr@777 1272 "Negative collection");
ysr@777 1273
ysr@777 1274 size_t freed_bytes =
ysr@777 1275 _cur_collection_pause_used_at_start_bytes - cur_used_bytes;
ysr@777 1276 size_t surviving_bytes = _collection_set_bytes_used_before - freed_bytes;
johnc@1829 1277
ysr@777 1278 double survival_fraction =
ysr@777 1279 (double)surviving_bytes/
ysr@777 1280 (double)_collection_set_bytes_used_before;
ysr@777 1281
ysr@777 1282 _n_pauses++;
ysr@777 1283
johnc@3021 1284 double ext_root_scan_time = avg_value(_par_last_ext_root_scan_times_ms);
johnc@3021 1285 double mark_stack_scan_time = avg_value(_par_last_mark_stack_scan_times_ms);
johnc@3021 1286 double update_rs_time = avg_value(_par_last_update_rs_times_ms);
johnc@3021 1287 double update_rs_processed_buffers =
johnc@3021 1288 sum_of_values(_par_last_update_rs_processed_buffers);
johnc@3021 1289 double scan_rs_time = avg_value(_par_last_scan_rs_times_ms);
johnc@3021 1290 double obj_copy_time = avg_value(_par_last_obj_copy_times_ms);
johnc@3021 1291 double termination_time = avg_value(_par_last_termination_times_ms);
johnc@3021 1292
johnc@3021 1293 double parallel_known_time = update_rs_time +
johnc@3021 1294 ext_root_scan_time +
johnc@3021 1295 mark_stack_scan_time +
johnc@3021 1296 scan_rs_time +
johnc@3021 1297 obj_copy_time +
johnc@3021 1298 termination_time;
johnc@3021 1299
johnc@3021 1300 double parallel_other_time = _cur_collection_par_time_ms - parallel_known_time;
johnc@3021 1301
johnc@3021 1302 PauseSummary* summary = _summary;
johnc@3021 1303
tonyp@1030 1304 if (update_stats) {
johnc@3021 1305 _recent_rs_scan_times_ms->add(scan_rs_time);
ysr@777 1306 _recent_pause_times_ms->add(elapsed_ms);
ysr@777 1307 _recent_rs_sizes->add(rs_size);
ysr@777 1308
johnc@3021 1309 MainBodySummary* body_summary = summary->main_body_summary();
johnc@3021 1310 guarantee(body_summary != NULL, "should not be null!");
johnc@3021 1311
johnc@3021 1312 if (_satb_drain_time_set)
johnc@3021 1313 body_summary->record_satb_drain_time_ms(_cur_satb_drain_time_ms);
johnc@3021 1314 else
johnc@3021 1315 body_summary->record_satb_drain_time_ms(0.0);
johnc@3021 1316
johnc@3021 1317 body_summary->record_ext_root_scan_time_ms(ext_root_scan_time);
johnc@3021 1318 body_summary->record_mark_stack_scan_time_ms(mark_stack_scan_time);
johnc@3021 1319 body_summary->record_update_rs_time_ms(update_rs_time);
johnc@3021 1320 body_summary->record_scan_rs_time_ms(scan_rs_time);
johnc@3021 1321 body_summary->record_obj_copy_time_ms(obj_copy_time);
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_clear_ct_time_ms(_cur_clear_ct_time_ms);
johnc@3021 1325 body_summary->record_termination_time_ms(termination_time);
johnc@3021 1326 body_summary->record_parallel_other_time_ms(parallel_other_time);
johnc@3021 1327 }
johnc@3021 1328 body_summary->record_mark_closure_time_ms(_mark_closure_time_ms);
johnc@3021 1329
ysr@777 1330 // We exempt parallel collection from this check because Alloc Buffer
ysr@777 1331 // fragmentation can produce negative collections. Same with evac
ysr@777 1332 // failure.
ysr@777 1333 // Further, we're now always doing parallel collection. But I'm still
ysr@777 1334 // leaving this here as a placeholder for a more precise assertion later.
ysr@777 1335 // (DLD, 10/05.
ysr@777 1336 assert((true || parallel)
ysr@777 1337 || _g1->evacuation_failed()
ysr@777 1338 || surviving_bytes <= _collection_set_bytes_used_before,
ysr@777 1339 "Or else negative collection!");
ysr@777 1340 _recent_CS_bytes_used_before->add(_collection_set_bytes_used_before);
ysr@777 1341 _recent_CS_bytes_surviving->add(surviving_bytes);
ysr@777 1342
ysr@777 1343 // this is where we update the allocation rate of the application
ysr@777 1344 double app_time_ms =
ysr@777 1345 (_cur_collection_start_sec * 1000.0 - _prev_collection_pause_end_ms);
ysr@777 1346 if (app_time_ms < MIN_TIMER_GRANULARITY) {
ysr@777 1347 // This usually happens due to the timer not having the required
ysr@777 1348 // granularity. Some Linuxes are the usual culprits.
ysr@777 1349 // We'll just set it to something (arbitrarily) small.
ysr@777 1350 app_time_ms = 1.0;
ysr@777 1351 }
ysr@777 1352 size_t regions_allocated =
ysr@777 1353 (_region_num_young - _prev_region_num_young) +
ysr@777 1354 (_region_num_tenured - _prev_region_num_tenured);
ysr@777 1355 double alloc_rate_ms = (double) regions_allocated / app_time_ms;
ysr@777 1356 _alloc_rate_ms_seq->add(alloc_rate_ms);
ysr@777 1357 _prev_region_num_young = _region_num_young;
ysr@777 1358 _prev_region_num_tenured = _region_num_tenured;
ysr@777 1359
ysr@777 1360 double interval_ms =
ysr@777 1361 (end_time_sec - _recent_prev_end_times_for_all_gcs_sec->oldest()) * 1000.0;
ysr@777 1362 update_recent_gc_times(end_time_sec, elapsed_ms);
ysr@777 1363 _recent_avg_pause_time_ratio = _recent_gc_times_ms->sum()/interval_ms;
ysr@1521 1364 if (recent_avg_pause_time_ratio() < 0.0 ||
ysr@1521 1365 (recent_avg_pause_time_ratio() - 1.0 > 0.0)) {
ysr@1521 1366 #ifndef PRODUCT
ysr@1521 1367 // Dump info to allow post-facto debugging
ysr@1521 1368 gclog_or_tty->print_cr("recent_avg_pause_time_ratio() out of bounds");
ysr@1521 1369 gclog_or_tty->print_cr("-------------------------------------------");
ysr@1521 1370 gclog_or_tty->print_cr("Recent GC Times (ms):");
ysr@1521 1371 _recent_gc_times_ms->dump();
ysr@1521 1372 gclog_or_tty->print_cr("(End Time=%3.3f) Recent GC End Times (s):", end_time_sec);
ysr@1521 1373 _recent_prev_end_times_for_all_gcs_sec->dump();
ysr@1521 1374 gclog_or_tty->print_cr("GC = %3.3f, Interval = %3.3f, Ratio = %3.3f",
ysr@1521 1375 _recent_gc_times_ms->sum(), interval_ms, recent_avg_pause_time_ratio());
ysr@1522 1376 // In debug mode, terminate the JVM if the user wants to debug at this point.
ysr@1522 1377 assert(!G1FailOnFPError, "Debugging data for CR 6898948 has been dumped above");
ysr@1522 1378 #endif // !PRODUCT
ysr@1522 1379 // Clip ratio between 0.0 and 1.0, and continue. This will be fixed in
ysr@1522 1380 // CR 6902692 by redoing the manner in which the ratio is incrementally computed.
ysr@1521 1381 if (_recent_avg_pause_time_ratio < 0.0) {
ysr@1521 1382 _recent_avg_pause_time_ratio = 0.0;
ysr@1521 1383 } else {
ysr@1521 1384 assert(_recent_avg_pause_time_ratio - 1.0 > 0.0, "Ctl-point invariant");
ysr@1521 1385 _recent_avg_pause_time_ratio = 1.0;
ysr@1521 1386 }
ysr@1521 1387 }
ysr@777 1388 }
ysr@777 1389
ysr@777 1390 if (G1PolicyVerbose > 1) {
ysr@777 1391 gclog_or_tty->print_cr(" Recording collection pause(%d)", _n_pauses);
ysr@777 1392 }
ysr@777 1393
ysr@777 1394 if (G1PolicyVerbose > 1) {
ysr@777 1395 gclog_or_tty->print_cr(" ET: %10.6f ms (avg: %10.6f ms)\n"
ysr@777 1396 " ET-RS: %10.6f ms (avg: %10.6f ms)\n"
ysr@777 1397 " |RS|: " SIZE_FORMAT,
ysr@777 1398 elapsed_ms, recent_avg_time_for_pauses_ms(),
johnc@3021 1399 scan_rs_time, recent_avg_time_for_rs_scan_ms(),
ysr@777 1400 rs_size);
ysr@777 1401
ysr@777 1402 gclog_or_tty->print_cr(" Used at start: " SIZE_FORMAT"K"
ysr@777 1403 " At end " SIZE_FORMAT "K\n"
ysr@777 1404 " garbage : " SIZE_FORMAT "K"
ysr@777 1405 " of " SIZE_FORMAT "K\n"
ysr@777 1406 " survival : %6.2f%% (%6.2f%% avg)",
ysr@777 1407 _cur_collection_pause_used_at_start_bytes/K,
ysr@777 1408 _g1->used()/K, freed_bytes/K,
ysr@777 1409 _collection_set_bytes_used_before/K,
ysr@777 1410 survival_fraction*100.0,
ysr@777 1411 recent_avg_survival_fraction()*100.0);
ysr@777 1412 gclog_or_tty->print_cr(" Recent %% gc pause time: %6.2f",
ysr@777 1413 recent_avg_pause_time_ratio() * 100.0);
ysr@777 1414 }
ysr@777 1415
ysr@777 1416 double other_time_ms = elapsed_ms;
ysr@777 1417
tonyp@2062 1418 if (_satb_drain_time_set) {
tonyp@2062 1419 other_time_ms -= _cur_satb_drain_time_ms;
ysr@777 1420 }
ysr@777 1421
tonyp@2062 1422 if (parallel) {
tonyp@2062 1423 other_time_ms -= _cur_collection_par_time_ms + _cur_clear_ct_time_ms;
tonyp@2062 1424 } else {
tonyp@2062 1425 other_time_ms -=
tonyp@2062 1426 update_rs_time +
tonyp@2062 1427 ext_root_scan_time + mark_stack_scan_time +
tonyp@2062 1428 scan_rs_time + obj_copy_time;
tonyp@2062 1429 }
tonyp@2062 1430
ysr@777 1431 if (PrintGCDetails) {
tonyp@2062 1432 gclog_or_tty->print_cr("%s, %1.8lf secs]",
ysr@777 1433 (last_pause_included_initial_mark) ? " (initial-mark)" : "",
ysr@777 1434 elapsed_ms / 1000.0);
ysr@777 1435
tonyp@2062 1436 if (_satb_drain_time_set) {
tonyp@2062 1437 print_stats(1, "SATB Drain Time", _cur_satb_drain_time_ms);
tonyp@2062 1438 }
tonyp@2062 1439 if (_last_satb_drain_processed_buffers >= 0) {
tonyp@2062 1440 print_stats(2, "Processed Buffers", _last_satb_drain_processed_buffers);
tonyp@2062 1441 }
tonyp@2062 1442 if (parallel) {
tonyp@2062 1443 print_stats(1, "Parallel Time", _cur_collection_par_time_ms);
brutisso@2712 1444 print_par_stats(2, "GC Worker Start Time", _par_last_gc_worker_start_times_ms);
tonyp@2062 1445 print_par_stats(2, "Update RS", _par_last_update_rs_times_ms);
brutisso@2712 1446 print_par_sizes(3, "Processed Buffers", _par_last_update_rs_processed_buffers);
brutisso@2712 1447 print_par_stats(2, "Ext Root Scanning", _par_last_ext_root_scan_times_ms);
brutisso@2712 1448 print_par_stats(2, "Mark Stack Scanning", _par_last_mark_stack_scan_times_ms);
tonyp@2062 1449 print_par_stats(2, "Scan RS", _par_last_scan_rs_times_ms);
tonyp@2062 1450 print_par_stats(2, "Object Copy", _par_last_obj_copy_times_ms);
tonyp@2062 1451 print_par_stats(2, "Termination", _par_last_termination_times_ms);
brutisso@2712 1452 print_par_sizes(3, "Termination Attempts", _par_last_termination_attempts);
brutisso@2712 1453 print_par_stats(2, "GC Worker End Time", _par_last_gc_worker_end_times_ms);
brutisso@2712 1454
brutisso@2712 1455 for (int i = 0; i < _parallel_gc_threads; i++) {
brutisso@2712 1456 _par_last_gc_worker_times_ms[i] = _par_last_gc_worker_end_times_ms[i] - _par_last_gc_worker_start_times_ms[i];
brutisso@2712 1457 }
brutisso@2712 1458 print_par_stats(2, "GC Worker Times", _par_last_gc_worker_times_ms);
brutisso@2712 1459
johnc@3021 1460 print_stats(2, "Parallel Other", parallel_other_time);
tonyp@2062 1461 print_stats(1, "Clear CT", _cur_clear_ct_time_ms);
tonyp@2062 1462 } else {
tonyp@2062 1463 print_stats(1, "Update RS", update_rs_time);
tonyp@2062 1464 print_stats(2, "Processed Buffers",
tonyp@2062 1465 (int)update_rs_processed_buffers);
tonyp@2062 1466 print_stats(1, "Ext Root Scanning", ext_root_scan_time);
tonyp@2062 1467 print_stats(1, "Mark Stack Scanning", mark_stack_scan_time);
tonyp@2062 1468 print_stats(1, "Scan RS", scan_rs_time);
tonyp@2062 1469 print_stats(1, "Object Copying", obj_copy_time);
ysr@777 1470 }
johnc@1325 1471 #ifndef PRODUCT
johnc@1325 1472 print_stats(1, "Cur Clear CC", _cur_clear_cc_time_ms);
johnc@1325 1473 print_stats(1, "Cum Clear CC", _cum_clear_cc_time_ms);
johnc@1325 1474 print_stats(1, "Min Clear CC", _min_clear_cc_time_ms);
johnc@1325 1475 print_stats(1, "Max Clear CC", _max_clear_cc_time_ms);
johnc@1325 1476 if (_num_cc_clears > 0) {
johnc@1325 1477 print_stats(1, "Avg Clear CC", _cum_clear_cc_time_ms / ((double)_num_cc_clears));
johnc@1325 1478 }
johnc@1325 1479 #endif
ysr@777 1480 print_stats(1, "Other", other_time_ms);
johnc@1829 1481 print_stats(2, "Choose CSet", _recorded_young_cset_choice_time_ms);
johnc@1829 1482
ysr@777 1483 for (int i = 0; i < _aux_num; ++i) {
ysr@777 1484 if (_cur_aux_times_set[i]) {
ysr@777 1485 char buffer[96];
ysr@777 1486 sprintf(buffer, "Aux%d", i);
ysr@777 1487 print_stats(1, buffer, _cur_aux_times_ms[i]);
ysr@777 1488 }
ysr@777 1489 }
ysr@777 1490 }
ysr@777 1491
ysr@777 1492 _all_pause_times_ms->add(elapsed_ms);
tonyp@1083 1493 if (update_stats) {
tonyp@1083 1494 summary->record_total_time_ms(elapsed_ms);
tonyp@1083 1495 summary->record_other_time_ms(other_time_ms);
tonyp@1083 1496 }
ysr@777 1497 for (int i = 0; i < _aux_num; ++i)
ysr@777 1498 if (_cur_aux_times_set[i])
ysr@777 1499 _all_aux_times_ms[i].add(_cur_aux_times_ms[i]);
ysr@777 1500
ysr@777 1501 // Reset marks-between-pauses counter.
ysr@777 1502 _n_marks_since_last_pause = 0;
ysr@777 1503
ysr@777 1504 // Update the efficiency-since-mark vars.
ysr@777 1505 double proc_ms = elapsed_ms * (double) _parallel_gc_threads;
ysr@777 1506 if (elapsed_ms < MIN_TIMER_GRANULARITY) {
ysr@777 1507 // This usually happens due to the timer not having the required
ysr@777 1508 // granularity. Some Linuxes are the usual culprits.
ysr@777 1509 // We'll just set it to something (arbitrarily) small.
ysr@777 1510 proc_ms = 1.0;
ysr@777 1511 }
ysr@777 1512 double cur_efficiency = (double) freed_bytes / proc_ms;
ysr@777 1513
ysr@777 1514 bool new_in_marking_window = _in_marking_window;
ysr@777 1515 bool new_in_marking_window_im = false;
tonyp@1794 1516 if (during_initial_mark_pause()) {
ysr@777 1517 new_in_marking_window = true;
ysr@777 1518 new_in_marking_window_im = true;
ysr@777 1519 }
ysr@777 1520
brutisso@3065 1521 if (_last_full_young_gc) {
tonyp@3114 1522 ergo_verbose2(ErgoPartiallyYoungGCs,
tonyp@3114 1523 "start partially-young GCs",
tonyp@3114 1524 ergo_format_byte_perc("known garbage"),
tonyp@3114 1525 _known_garbage_bytes, _known_garbage_ratio * 100.0);
brutisso@3065 1526 set_full_young_gcs(false);
brutisso@3065 1527 _last_full_young_gc = false;
brutisso@3065 1528 }
brutisso@3065 1529
brutisso@3065 1530 if ( !_last_young_gc_full ) {
tonyp@3114 1531 if (_should_revert_to_full_young_gcs) {
tonyp@3114 1532 ergo_verbose2(ErgoPartiallyYoungGCs,
tonyp@3114 1533 "end partially-young GCs",
tonyp@3114 1534 ergo_format_reason("partially-young GCs end requested")
tonyp@3114 1535 ergo_format_byte_perc("known garbage"),
tonyp@3114 1536 _known_garbage_bytes, _known_garbage_ratio * 100.0);
tonyp@3114 1537 set_full_young_gcs(true);
tonyp@3114 1538 } else if (_known_garbage_ratio < 0.05) {
tonyp@3114 1539 ergo_verbose3(ErgoPartiallyYoungGCs,
tonyp@3114 1540 "end partially-young GCs",
tonyp@3114 1541 ergo_format_reason("known garbage percent lower than threshold")
tonyp@3114 1542 ergo_format_byte_perc("known garbage")
tonyp@3114 1543 ergo_format_perc("threshold"),
tonyp@3114 1544 _known_garbage_bytes, _known_garbage_ratio * 100.0,
tonyp@3114 1545 0.05 * 100.0);
tonyp@3114 1546 set_full_young_gcs(true);
tonyp@3114 1547 } else if (adaptive_young_list_length() &&
tonyp@3114 1548 (get_gc_eff_factor() * cur_efficiency < predict_young_gc_eff())) {
tonyp@3114 1549 ergo_verbose5(ErgoPartiallyYoungGCs,
tonyp@3114 1550 "end partially-young GCs",
tonyp@3114 1551 ergo_format_reason("current GC efficiency lower than "
tonyp@3114 1552 "predicted fully-young GC efficiency")
tonyp@3114 1553 ergo_format_double("GC efficiency factor")
tonyp@3114 1554 ergo_format_double("current GC efficiency")
tonyp@3114 1555 ergo_format_double("predicted fully-young GC efficiency")
tonyp@3114 1556 ergo_format_byte_perc("known garbage"),
tonyp@3114 1557 get_gc_eff_factor(), cur_efficiency,
tonyp@3114 1558 predict_young_gc_eff(),
tonyp@3114 1559 _known_garbage_bytes, _known_garbage_ratio * 100.0);
tonyp@3114 1560 set_full_young_gcs(true);
ysr@777 1561 }
brutisso@3065 1562 }
brutisso@3065 1563 _should_revert_to_full_young_gcs = false;
brutisso@3065 1564
brutisso@3065 1565 if (_last_young_gc_full && !_during_marking) {
brutisso@3065 1566 _young_gc_eff_seq->add(cur_efficiency);
ysr@777 1567 }
ysr@777 1568
ysr@777 1569 _short_lived_surv_rate_group->start_adding_regions();
ysr@777 1570 // do that for any other surv rate groupsx
ysr@777 1571
ysr@777 1572 // <NEW PREDICTION>
ysr@777 1573
apetrusenko@1112 1574 if (update_stats) {
ysr@777 1575 double pause_time_ms = elapsed_ms;
ysr@777 1576
ysr@777 1577 size_t diff = 0;
ysr@777 1578 if (_max_pending_cards >= _pending_cards)
ysr@777 1579 diff = _max_pending_cards - _pending_cards;
ysr@777 1580 _pending_card_diff_seq->add((double) diff);
ysr@777 1581
ysr@777 1582 double cost_per_card_ms = 0.0;
ysr@777 1583 if (_pending_cards > 0) {
ysr@777 1584 cost_per_card_ms = update_rs_time / (double) _pending_cards;
ysr@777 1585 _cost_per_card_ms_seq->add(cost_per_card_ms);
ysr@777 1586 }
ysr@777 1587
ysr@777 1588 size_t cards_scanned = _g1->cards_scanned();
ysr@777 1589
ysr@777 1590 double cost_per_entry_ms = 0.0;
ysr@777 1591 if (cards_scanned > 10) {
ysr@777 1592 cost_per_entry_ms = scan_rs_time / (double) cards_scanned;
ysr@777 1593 if (_last_young_gc_full)
ysr@777 1594 _cost_per_entry_ms_seq->add(cost_per_entry_ms);
ysr@777 1595 else
ysr@777 1596 _partially_young_cost_per_entry_ms_seq->add(cost_per_entry_ms);
ysr@777 1597 }
ysr@777 1598
ysr@777 1599 if (_max_rs_lengths > 0) {
ysr@777 1600 double cards_per_entry_ratio =
ysr@777 1601 (double) cards_scanned / (double) _max_rs_lengths;
ysr@777 1602 if (_last_young_gc_full)
ysr@777 1603 _fully_young_cards_per_entry_ratio_seq->add(cards_per_entry_ratio);
ysr@777 1604 else
ysr@777 1605 _partially_young_cards_per_entry_ratio_seq->add(cards_per_entry_ratio);
ysr@777 1606 }
ysr@777 1607
ysr@777 1608 size_t rs_length_diff = _max_rs_lengths - _recorded_rs_lengths;
ysr@777 1609 if (rs_length_diff >= 0)
ysr@777 1610 _rs_length_diff_seq->add((double) rs_length_diff);
ysr@777 1611
ysr@777 1612 size_t copied_bytes = surviving_bytes;
ysr@777 1613 double cost_per_byte_ms = 0.0;
ysr@777 1614 if (copied_bytes > 0) {
ysr@777 1615 cost_per_byte_ms = obj_copy_time / (double) copied_bytes;
ysr@777 1616 if (_in_marking_window)
ysr@777 1617 _cost_per_byte_ms_during_cm_seq->add(cost_per_byte_ms);
ysr@777 1618 else
ysr@777 1619 _cost_per_byte_ms_seq->add(cost_per_byte_ms);
ysr@777 1620 }
ysr@777 1621
ysr@777 1622 double all_other_time_ms = pause_time_ms -
johnc@1829 1623 (update_rs_time + scan_rs_time + obj_copy_time +
ysr@777 1624 _mark_closure_time_ms + termination_time);
ysr@777 1625
ysr@777 1626 double young_other_time_ms = 0.0;
ysr@777 1627 if (_recorded_young_regions > 0) {
ysr@777 1628 young_other_time_ms =
ysr@777 1629 _recorded_young_cset_choice_time_ms +
ysr@777 1630 _recorded_young_free_cset_time_ms;
ysr@777 1631 _young_other_cost_per_region_ms_seq->add(young_other_time_ms /
ysr@777 1632 (double) _recorded_young_regions);
ysr@777 1633 }
ysr@777 1634 double non_young_other_time_ms = 0.0;
ysr@777 1635 if (_recorded_non_young_regions > 0) {
ysr@777 1636 non_young_other_time_ms =
ysr@777 1637 _recorded_non_young_cset_choice_time_ms +
ysr@777 1638 _recorded_non_young_free_cset_time_ms;
ysr@777 1639
ysr@777 1640 _non_young_other_cost_per_region_ms_seq->add(non_young_other_time_ms /
ysr@777 1641 (double) _recorded_non_young_regions);
ysr@777 1642 }
ysr@777 1643
ysr@777 1644 double constant_other_time_ms = all_other_time_ms -
ysr@777 1645 (young_other_time_ms + non_young_other_time_ms);
ysr@777 1646 _constant_other_time_ms_seq->add(constant_other_time_ms);
ysr@777 1647
ysr@777 1648 double survival_ratio = 0.0;
ysr@777 1649 if (_bytes_in_collection_set_before_gc > 0) {
tonyp@3028 1650 survival_ratio = (double) _bytes_copied_during_gc /
tonyp@3028 1651 (double) _bytes_in_collection_set_before_gc;
ysr@777 1652 }
ysr@777 1653
ysr@777 1654 _pending_cards_seq->add((double) _pending_cards);
ysr@777 1655 _scanned_cards_seq->add((double) cards_scanned);
ysr@777 1656 _rs_lengths_seq->add((double) _max_rs_lengths);
ysr@777 1657
ysr@777 1658 double expensive_region_limit_ms =
johnc@1186 1659 (double) MaxGCPauseMillis - predict_constant_other_time_ms();
ysr@777 1660 if (expensive_region_limit_ms < 0.0) {
ysr@777 1661 // this means that the other time was predicted to be longer than
ysr@777 1662 // than the max pause time
johnc@1186 1663 expensive_region_limit_ms = (double) MaxGCPauseMillis;
ysr@777 1664 }
ysr@777 1665 _expensive_region_limit_ms = expensive_region_limit_ms;
ysr@777 1666
ysr@777 1667 if (PREDICTIONS_VERBOSE) {
ysr@777 1668 gclog_or_tty->print_cr("");
ysr@777 1669 gclog_or_tty->print_cr("PREDICTIONS %1.4lf %d "
johnc@1829 1670 "REGIONS %d %d %d "
ysr@777 1671 "PENDING_CARDS %d %d "
ysr@777 1672 "CARDS_SCANNED %d %d "
ysr@777 1673 "RS_LENGTHS %d %d "
ysr@777 1674 "RS_UPDATE %1.6lf %1.6lf RS_SCAN %1.6lf %1.6lf "
ysr@777 1675 "SURVIVAL_RATIO %1.6lf %1.6lf "
ysr@777 1676 "OBJECT_COPY %1.6lf %1.6lf OTHER_CONSTANT %1.6lf %1.6lf "
ysr@777 1677 "OTHER_YOUNG %1.6lf %1.6lf "
ysr@777 1678 "OTHER_NON_YOUNG %1.6lf %1.6lf "
ysr@777 1679 "VTIME_DIFF %1.6lf TERMINATION %1.6lf "
ysr@777 1680 "ELAPSED %1.6lf %1.6lf ",
ysr@777 1681 _cur_collection_start_sec,
ysr@777 1682 (!_last_young_gc_full) ? 2 :
ysr@777 1683 (last_pause_included_initial_mark) ? 1 : 0,
ysr@777 1684 _recorded_region_num,
ysr@777 1685 _recorded_young_regions,
ysr@777 1686 _recorded_non_young_regions,
ysr@777 1687 _predicted_pending_cards, _pending_cards,
ysr@777 1688 _predicted_cards_scanned, cards_scanned,
ysr@777 1689 _predicted_rs_lengths, _max_rs_lengths,
ysr@777 1690 _predicted_rs_update_time_ms, update_rs_time,
ysr@777 1691 _predicted_rs_scan_time_ms, scan_rs_time,
ysr@777 1692 _predicted_survival_ratio, survival_ratio,
ysr@777 1693 _predicted_object_copy_time_ms, obj_copy_time,
ysr@777 1694 _predicted_constant_other_time_ms, constant_other_time_ms,
ysr@777 1695 _predicted_young_other_time_ms, young_other_time_ms,
ysr@777 1696 _predicted_non_young_other_time_ms,
ysr@777 1697 non_young_other_time_ms,
ysr@777 1698 _vtime_diff_ms, termination_time,
ysr@777 1699 _predicted_pause_time_ms, elapsed_ms);
ysr@777 1700 }
ysr@777 1701
ysr@777 1702 if (G1PolicyVerbose > 0) {
ysr@777 1703 gclog_or_tty->print_cr("Pause Time, predicted: %1.4lfms (predicted %s), actual: %1.4lfms",
ysr@777 1704 _predicted_pause_time_ms,
ysr@777 1705 (_within_target) ? "within" : "outside",
ysr@777 1706 elapsed_ms);
ysr@777 1707 }
ysr@777 1708
ysr@777 1709 }
ysr@777 1710
ysr@777 1711 _in_marking_window = new_in_marking_window;
ysr@777 1712 _in_marking_window_im = new_in_marking_window_im;
ysr@777 1713 _free_regions_at_end_of_collection = _g1->free_regions();
tonyp@3119 1714 update_young_list_target_length();
ysr@777 1715
iveresov@1546 1716 // Note that _mmu_tracker->max_gc_time() returns the time in seconds.
tonyp@1717 1717 double update_rs_time_goal_ms = _mmu_tracker->max_gc_time() * MILLIUNITS * G1RSetUpdatingPauseTimePercent / 100.0;
iveresov@1546 1718 adjust_concurrent_refinement(update_rs_time, update_rs_processed_buffers, update_rs_time_goal_ms);
ysr@777 1719 // </NEW PREDICTION>
ysr@777 1720 }
ysr@777 1721
tonyp@2961 1722 #define EXT_SIZE_FORMAT "%d%s"
tonyp@2961 1723 #define EXT_SIZE_PARAMS(bytes) \
tonyp@2961 1724 byte_size_in_proper_unit((bytes)), \
tonyp@2961 1725 proper_unit_for_byte_size((bytes))
tonyp@2961 1726
tonyp@2961 1727 void G1CollectorPolicy::print_heap_transition() {
tonyp@2961 1728 if (PrintGCDetails) {
tonyp@2961 1729 YoungList* young_list = _g1->young_list();
tonyp@2961 1730 size_t eden_bytes = young_list->eden_used_bytes();
tonyp@2961 1731 size_t survivor_bytes = young_list->survivor_used_bytes();
tonyp@2961 1732 size_t used_before_gc = _cur_collection_pause_used_at_start_bytes;
tonyp@2961 1733 size_t used = _g1->used();
tonyp@2961 1734 size_t capacity = _g1->capacity();
brutisso@3120 1735 size_t eden_capacity =
brutisso@3120 1736 (_young_list_target_length * HeapRegion::GrainBytes) - survivor_bytes;
tonyp@2961 1737
tonyp@2961 1738 gclog_or_tty->print_cr(
brutisso@3120 1739 " [Eden: "EXT_SIZE_FORMAT"("EXT_SIZE_FORMAT")->"EXT_SIZE_FORMAT"("EXT_SIZE_FORMAT") "
brutisso@3120 1740 "Survivors: "EXT_SIZE_FORMAT"->"EXT_SIZE_FORMAT" "
brutisso@3120 1741 "Heap: "EXT_SIZE_FORMAT"("EXT_SIZE_FORMAT")->"
brutisso@3120 1742 EXT_SIZE_FORMAT"("EXT_SIZE_FORMAT")]",
brutisso@3120 1743 EXT_SIZE_PARAMS(_eden_bytes_before_gc),
brutisso@3120 1744 EXT_SIZE_PARAMS(_prev_eden_capacity),
brutisso@3120 1745 EXT_SIZE_PARAMS(eden_bytes),
brutisso@3120 1746 EXT_SIZE_PARAMS(eden_capacity),
brutisso@3120 1747 EXT_SIZE_PARAMS(_survivor_bytes_before_gc),
brutisso@3120 1748 EXT_SIZE_PARAMS(survivor_bytes),
brutisso@3120 1749 EXT_SIZE_PARAMS(used_before_gc),
brutisso@3120 1750 EXT_SIZE_PARAMS(_capacity_before_gc),
brutisso@3120 1751 EXT_SIZE_PARAMS(used),
brutisso@3120 1752 EXT_SIZE_PARAMS(capacity));
brutisso@3120 1753
brutisso@3120 1754 _prev_eden_capacity = eden_capacity;
tonyp@2961 1755 } else if (PrintGC) {
tonyp@2961 1756 _g1->print_size_transition(gclog_or_tty,
tonyp@2961 1757 _cur_collection_pause_used_at_start_bytes,
tonyp@2961 1758 _g1->used(), _g1->capacity());
tonyp@2961 1759 }
tonyp@2961 1760 }
tonyp@2961 1761
ysr@777 1762 // <NEW PREDICTION>
ysr@777 1763
iveresov@1546 1764 void G1CollectorPolicy::adjust_concurrent_refinement(double update_rs_time,
iveresov@1546 1765 double update_rs_processed_buffers,
iveresov@1546 1766 double goal_ms) {
iveresov@1546 1767 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set();
iveresov@1546 1768 ConcurrentG1Refine *cg1r = G1CollectedHeap::heap()->concurrent_g1_refine();
iveresov@1546 1769
tonyp@1717 1770 if (G1UseAdaptiveConcRefinement) {
iveresov@1546 1771 const int k_gy = 3, k_gr = 6;
iveresov@1546 1772 const double inc_k = 1.1, dec_k = 0.9;
iveresov@1546 1773
iveresov@1546 1774 int g = cg1r->green_zone();
iveresov@1546 1775 if (update_rs_time > goal_ms) {
iveresov@1546 1776 g = (int)(g * dec_k); // Can become 0, that's OK. That would mean a mutator-only processing.
iveresov@1546 1777 } else {
iveresov@1546 1778 if (update_rs_time < goal_ms && update_rs_processed_buffers > g) {
iveresov@1546 1779 g = (int)MAX2(g * inc_k, g + 1.0);
iveresov@1546 1780 }
iveresov@1546 1781 }
iveresov@1546 1782 // Change the refinement threads params
iveresov@1546 1783 cg1r->set_green_zone(g);
iveresov@1546 1784 cg1r->set_yellow_zone(g * k_gy);
iveresov@1546 1785 cg1r->set_red_zone(g * k_gr);
iveresov@1546 1786 cg1r->reinitialize_threads();
iveresov@1546 1787
iveresov@1546 1788 int processing_threshold_delta = MAX2((int)(cg1r->green_zone() * sigma()), 1);
iveresov@1546 1789 int processing_threshold = MIN2(cg1r->green_zone() + processing_threshold_delta,
iveresov@1546 1790 cg1r->yellow_zone());
iveresov@1546 1791 // Change the barrier params
iveresov@1546 1792 dcqs.set_process_completed_threshold(processing_threshold);
iveresov@1546 1793 dcqs.set_max_completed_queue(cg1r->red_zone());
iveresov@1546 1794 }
iveresov@1546 1795
iveresov@1546 1796 int curr_queue_size = dcqs.completed_buffers_num();
iveresov@1546 1797 if (curr_queue_size >= cg1r->yellow_zone()) {
iveresov@1546 1798 dcqs.set_completed_queue_padding(curr_queue_size);
iveresov@1546 1799 } else {
iveresov@1546 1800 dcqs.set_completed_queue_padding(0);
iveresov@1546 1801 }
iveresov@1546 1802 dcqs.notify_if_necessary();
iveresov@1546 1803 }
iveresov@1546 1804
ysr@777 1805 double
ysr@777 1806 G1CollectorPolicy::
ysr@777 1807 predict_young_collection_elapsed_time_ms(size_t adjustment) {
ysr@777 1808 guarantee( adjustment == 0 || adjustment == 1, "invariant" );
ysr@777 1809
ysr@777 1810 G1CollectedHeap* g1h = G1CollectedHeap::heap();
johnc@1829 1811 size_t young_num = g1h->young_list()->length();
ysr@777 1812 if (young_num == 0)
ysr@777 1813 return 0.0;
ysr@777 1814
ysr@777 1815 young_num += adjustment;
ysr@777 1816 size_t pending_cards = predict_pending_cards();
johnc@1829 1817 size_t rs_lengths = g1h->young_list()->sampled_rs_lengths() +
ysr@777 1818 predict_rs_length_diff();
ysr@777 1819 size_t card_num;
ysr@777 1820 if (full_young_gcs())
ysr@777 1821 card_num = predict_young_card_num(rs_lengths);
ysr@777 1822 else
ysr@777 1823 card_num = predict_non_young_card_num(rs_lengths);
ysr@777 1824 size_t young_byte_size = young_num * HeapRegion::GrainBytes;
ysr@777 1825 double accum_yg_surv_rate =
ysr@777 1826 _short_lived_surv_rate_group->accum_surv_rate(adjustment);
ysr@777 1827
ysr@777 1828 size_t bytes_to_copy =
ysr@777 1829 (size_t) (accum_yg_surv_rate * (double) HeapRegion::GrainBytes);
ysr@777 1830
ysr@777 1831 return
ysr@777 1832 predict_rs_update_time_ms(pending_cards) +
ysr@777 1833 predict_rs_scan_time_ms(card_num) +
ysr@777 1834 predict_object_copy_time_ms(bytes_to_copy) +
ysr@777 1835 predict_young_other_time_ms(young_num) +
ysr@777 1836 predict_constant_other_time_ms();
ysr@777 1837 }
ysr@777 1838
ysr@777 1839 double
ysr@777 1840 G1CollectorPolicy::predict_base_elapsed_time_ms(size_t pending_cards) {
ysr@777 1841 size_t rs_length = predict_rs_length_diff();
ysr@777 1842 size_t card_num;
ysr@777 1843 if (full_young_gcs())
ysr@777 1844 card_num = predict_young_card_num(rs_length);
ysr@777 1845 else
ysr@777 1846 card_num = predict_non_young_card_num(rs_length);
ysr@777 1847 return predict_base_elapsed_time_ms(pending_cards, card_num);
ysr@777 1848 }
ysr@777 1849
ysr@777 1850 double
ysr@777 1851 G1CollectorPolicy::predict_base_elapsed_time_ms(size_t pending_cards,
ysr@777 1852 size_t scanned_cards) {
ysr@777 1853 return
ysr@777 1854 predict_rs_update_time_ms(pending_cards) +
ysr@777 1855 predict_rs_scan_time_ms(scanned_cards) +
ysr@777 1856 predict_constant_other_time_ms();
ysr@777 1857 }
ysr@777 1858
ysr@777 1859 double
ysr@777 1860 G1CollectorPolicy::predict_region_elapsed_time_ms(HeapRegion* hr,
ysr@777 1861 bool young) {
ysr@777 1862 size_t rs_length = hr->rem_set()->occupied();
ysr@777 1863 size_t card_num;
ysr@777 1864 if (full_young_gcs())
ysr@777 1865 card_num = predict_young_card_num(rs_length);
ysr@777 1866 else
ysr@777 1867 card_num = predict_non_young_card_num(rs_length);
ysr@777 1868 size_t bytes_to_copy = predict_bytes_to_copy(hr);
ysr@777 1869
ysr@777 1870 double region_elapsed_time_ms =
ysr@777 1871 predict_rs_scan_time_ms(card_num) +
ysr@777 1872 predict_object_copy_time_ms(bytes_to_copy);
ysr@777 1873
ysr@777 1874 if (young)
ysr@777 1875 region_elapsed_time_ms += predict_young_other_time_ms(1);
ysr@777 1876 else
ysr@777 1877 region_elapsed_time_ms += predict_non_young_other_time_ms(1);
ysr@777 1878
ysr@777 1879 return region_elapsed_time_ms;
ysr@777 1880 }
ysr@777 1881
ysr@777 1882 size_t
ysr@777 1883 G1CollectorPolicy::predict_bytes_to_copy(HeapRegion* hr) {
ysr@777 1884 size_t bytes_to_copy;
ysr@777 1885 if (hr->is_marked())
ysr@777 1886 bytes_to_copy = hr->max_live_bytes();
ysr@777 1887 else {
ysr@777 1888 guarantee( hr->is_young() && hr->age_in_surv_rate_group() != -1,
ysr@777 1889 "invariant" );
ysr@777 1890 int age = hr->age_in_surv_rate_group();
apetrusenko@980 1891 double yg_surv_rate = predict_yg_surv_rate(age, hr->surv_rate_group());
ysr@777 1892 bytes_to_copy = (size_t) ((double) hr->used() * yg_surv_rate);
ysr@777 1893 }
ysr@777 1894
ysr@777 1895 return bytes_to_copy;
ysr@777 1896 }
ysr@777 1897
ysr@777 1898 void
ysr@777 1899 G1CollectorPolicy::start_recording_regions() {
ysr@777 1900 _recorded_rs_lengths = 0;
ysr@777 1901 _recorded_young_regions = 0;
ysr@777 1902 _recorded_non_young_regions = 0;
ysr@777 1903
ysr@777 1904 #if PREDICTIONS_VERBOSE
ysr@777 1905 _recorded_marked_bytes = 0;
ysr@777 1906 _recorded_young_bytes = 0;
ysr@777 1907 _predicted_bytes_to_copy = 0;
johnc@1829 1908 _predicted_rs_lengths = 0;
johnc@1829 1909 _predicted_cards_scanned = 0;
ysr@777 1910 #endif // PREDICTIONS_VERBOSE
ysr@777 1911 }
ysr@777 1912
ysr@777 1913 void
johnc@1829 1914 G1CollectorPolicy::record_cset_region_info(HeapRegion* hr, bool young) {
ysr@777 1915 #if PREDICTIONS_VERBOSE
johnc@1829 1916 if (!young) {
ysr@777 1917 _recorded_marked_bytes += hr->max_live_bytes();
ysr@777 1918 }
ysr@777 1919 _predicted_bytes_to_copy += predict_bytes_to_copy(hr);
ysr@777 1920 #endif // PREDICTIONS_VERBOSE
ysr@777 1921
ysr@777 1922 size_t rs_length = hr->rem_set()->occupied();
ysr@777 1923 _recorded_rs_lengths += rs_length;
ysr@777 1924 }
ysr@777 1925
ysr@777 1926 void
johnc@1829 1927 G1CollectorPolicy::record_non_young_cset_region(HeapRegion* hr) {
johnc@1829 1928 assert(!hr->is_young(), "should not call this");
johnc@1829 1929 ++_recorded_non_young_regions;
johnc@1829 1930 record_cset_region_info(hr, false);
johnc@1829 1931 }
johnc@1829 1932
johnc@1829 1933 void
johnc@1829 1934 G1CollectorPolicy::set_recorded_young_regions(size_t n_regions) {
johnc@1829 1935 _recorded_young_regions = n_regions;
johnc@1829 1936 }
johnc@1829 1937
johnc@1829 1938 void G1CollectorPolicy::set_recorded_young_bytes(size_t bytes) {
johnc@1829 1939 #if PREDICTIONS_VERBOSE
johnc@1829 1940 _recorded_young_bytes = bytes;
johnc@1829 1941 #endif // PREDICTIONS_VERBOSE
johnc@1829 1942 }
johnc@1829 1943
johnc@1829 1944 void G1CollectorPolicy::set_recorded_rs_lengths(size_t rs_lengths) {
johnc@1829 1945 _recorded_rs_lengths = rs_lengths;
johnc@1829 1946 }
johnc@1829 1947
johnc@1829 1948 void G1CollectorPolicy::set_predicted_bytes_to_copy(size_t bytes) {
johnc@1829 1949 _predicted_bytes_to_copy = bytes;
ysr@777 1950 }
ysr@777 1951
ysr@777 1952 void
ysr@777 1953 G1CollectorPolicy::end_recording_regions() {
johnc@1829 1954 // The _predicted_pause_time_ms field is referenced in code
johnc@1829 1955 // not under PREDICTIONS_VERBOSE. Let's initialize it.
johnc@1829 1956 _predicted_pause_time_ms = -1.0;
johnc@1829 1957
ysr@777 1958 #if PREDICTIONS_VERBOSE
ysr@777 1959 _predicted_pending_cards = predict_pending_cards();
ysr@777 1960 _predicted_rs_lengths = _recorded_rs_lengths + predict_rs_length_diff();
ysr@777 1961 if (full_young_gcs())
ysr@777 1962 _predicted_cards_scanned += predict_young_card_num(_predicted_rs_lengths);
ysr@777 1963 else
ysr@777 1964 _predicted_cards_scanned +=
ysr@777 1965 predict_non_young_card_num(_predicted_rs_lengths);
ysr@777 1966 _recorded_region_num = _recorded_young_regions + _recorded_non_young_regions;
ysr@777 1967
ysr@777 1968 _predicted_rs_update_time_ms =
ysr@777 1969 predict_rs_update_time_ms(_g1->pending_card_num());
ysr@777 1970 _predicted_rs_scan_time_ms =
ysr@777 1971 predict_rs_scan_time_ms(_predicted_cards_scanned);
ysr@777 1972 _predicted_object_copy_time_ms =
ysr@777 1973 predict_object_copy_time_ms(_predicted_bytes_to_copy);
ysr@777 1974 _predicted_constant_other_time_ms =
ysr@777 1975 predict_constant_other_time_ms();
ysr@777 1976 _predicted_young_other_time_ms =
ysr@777 1977 predict_young_other_time_ms(_recorded_young_regions);
ysr@777 1978 _predicted_non_young_other_time_ms =
ysr@777 1979 predict_non_young_other_time_ms(_recorded_non_young_regions);
ysr@777 1980
ysr@777 1981 _predicted_pause_time_ms =
ysr@777 1982 _predicted_rs_update_time_ms +
ysr@777 1983 _predicted_rs_scan_time_ms +
ysr@777 1984 _predicted_object_copy_time_ms +
ysr@777 1985 _predicted_constant_other_time_ms +
ysr@777 1986 _predicted_young_other_time_ms +
ysr@777 1987 _predicted_non_young_other_time_ms;
ysr@777 1988 #endif // PREDICTIONS_VERBOSE
ysr@777 1989 }
ysr@777 1990
ysr@777 1991 void G1CollectorPolicy::check_if_region_is_too_expensive(double
ysr@777 1992 predicted_time_ms) {
ysr@777 1993 // I don't think we need to do this when in young GC mode since
ysr@777 1994 // marking will be initiated next time we hit the soft limit anyway...
ysr@777 1995 if (predicted_time_ms > _expensive_region_limit_ms) {
tonyp@3114 1996 ergo_verbose2(ErgoPartiallyYoungGCs,
tonyp@3114 1997 "request partially-young GCs end",
tonyp@3114 1998 ergo_format_reason("predicted region time higher than threshold")
tonyp@3114 1999 ergo_format_ms("predicted region time")
tonyp@3114 2000 ergo_format_ms("threshold"),
tonyp@3114 2001 predicted_time_ms, _expensive_region_limit_ms);
brutisso@3065 2002 // no point in doing another partial one
brutisso@3065 2003 _should_revert_to_full_young_gcs = true;
ysr@777 2004 }
ysr@777 2005 }
ysr@777 2006
ysr@777 2007 // </NEW PREDICTION>
ysr@777 2008
ysr@777 2009
ysr@777 2010 void G1CollectorPolicy::update_recent_gc_times(double end_time_sec,
ysr@777 2011 double elapsed_ms) {
ysr@777 2012 _recent_gc_times_ms->add(elapsed_ms);
ysr@777 2013 _recent_prev_end_times_for_all_gcs_sec->add(end_time_sec);
ysr@777 2014 _prev_collection_pause_end_ms = end_time_sec * 1000.0;
ysr@777 2015 }
ysr@777 2016
ysr@777 2017 double G1CollectorPolicy::recent_avg_time_for_pauses_ms() {
johnc@3021 2018 if (_recent_pause_times_ms->num() == 0) {
johnc@3021 2019 return (double) MaxGCPauseMillis;
johnc@3021 2020 }
johnc@3021 2021 return _recent_pause_times_ms->avg();
ysr@777 2022 }
ysr@777 2023
johnc@3021 2024 double G1CollectorPolicy::recent_avg_time_for_rs_scan_ms() {
johnc@3021 2025 if (_recent_rs_scan_times_ms->num() == 0) {
johnc@1186 2026 return (double)MaxGCPauseMillis/3.0;
johnc@3021 2027 }
johnc@3021 2028 return _recent_rs_scan_times_ms->avg();
ysr@777 2029 }
ysr@777 2030
ysr@777 2031 int G1CollectorPolicy::number_of_recent_gcs() {
johnc@3021 2032 assert(_recent_rs_scan_times_ms->num() ==
ysr@777 2033 _recent_pause_times_ms->num(), "Sequence out of sync");
ysr@777 2034 assert(_recent_pause_times_ms->num() ==
ysr@777 2035 _recent_CS_bytes_used_before->num(), "Sequence out of sync");
ysr@777 2036 assert(_recent_CS_bytes_used_before->num() ==
ysr@777 2037 _recent_CS_bytes_surviving->num(), "Sequence out of sync");
johnc@3021 2038
ysr@777 2039 return _recent_pause_times_ms->num();
ysr@777 2040 }
ysr@777 2041
ysr@777 2042 double G1CollectorPolicy::recent_avg_survival_fraction() {
ysr@777 2043 return recent_avg_survival_fraction_work(_recent_CS_bytes_surviving,
ysr@777 2044 _recent_CS_bytes_used_before);
ysr@777 2045 }
ysr@777 2046
ysr@777 2047 double G1CollectorPolicy::last_survival_fraction() {
ysr@777 2048 return last_survival_fraction_work(_recent_CS_bytes_surviving,
ysr@777 2049 _recent_CS_bytes_used_before);
ysr@777 2050 }
ysr@777 2051
ysr@777 2052 double
ysr@777 2053 G1CollectorPolicy::recent_avg_survival_fraction_work(TruncatedSeq* surviving,
ysr@777 2054 TruncatedSeq* before) {
ysr@777 2055 assert(surviving->num() == before->num(), "Sequence out of sync");
ysr@777 2056 if (before->sum() > 0.0) {
ysr@777 2057 double recent_survival_rate = surviving->sum() / before->sum();
ysr@777 2058 // We exempt parallel collection from this check because Alloc Buffer
ysr@777 2059 // fragmentation can produce negative collections.
ysr@777 2060 // Further, we're now always doing parallel collection. But I'm still
ysr@777 2061 // leaving this here as a placeholder for a more precise assertion later.
ysr@777 2062 // (DLD, 10/05.)
jmasa@2188 2063 assert((true || G1CollectedHeap::use_parallel_gc_threads()) ||
ysr@777 2064 _g1->evacuation_failed() ||
ysr@777 2065 recent_survival_rate <= 1.0, "Or bad frac");
ysr@777 2066 return recent_survival_rate;
ysr@777 2067 } else {
ysr@777 2068 return 1.0; // Be conservative.
ysr@777 2069 }
ysr@777 2070 }
ysr@777 2071
ysr@777 2072 double
ysr@777 2073 G1CollectorPolicy::last_survival_fraction_work(TruncatedSeq* surviving,
ysr@777 2074 TruncatedSeq* before) {
ysr@777 2075 assert(surviving->num() == before->num(), "Sequence out of sync");
ysr@777 2076 if (surviving->num() > 0 && before->last() > 0.0) {
ysr@777 2077 double last_survival_rate = surviving->last() / before->last();
ysr@777 2078 // We exempt parallel collection from this check because Alloc Buffer
ysr@777 2079 // fragmentation can produce negative collections.
ysr@777 2080 // Further, we're now always doing parallel collection. But I'm still
ysr@777 2081 // leaving this here as a placeholder for a more precise assertion later.
ysr@777 2082 // (DLD, 10/05.)
jmasa@2188 2083 assert((true || G1CollectedHeap::use_parallel_gc_threads()) ||
ysr@777 2084 last_survival_rate <= 1.0, "Or bad frac");
ysr@777 2085 return last_survival_rate;
ysr@777 2086 } else {
ysr@777 2087 return 1.0;
ysr@777 2088 }
ysr@777 2089 }
ysr@777 2090
ysr@777 2091 static const int survival_min_obs = 5;
ysr@777 2092 static double survival_min_obs_limits[] = { 0.9, 0.7, 0.5, 0.3, 0.1 };
ysr@777 2093 static const double min_survival_rate = 0.1;
ysr@777 2094
ysr@777 2095 double
ysr@777 2096 G1CollectorPolicy::conservative_avg_survival_fraction_work(double avg,
ysr@777 2097 double latest) {
ysr@777 2098 double res = avg;
ysr@777 2099 if (number_of_recent_gcs() < survival_min_obs) {
ysr@777 2100 res = MAX2(res, survival_min_obs_limits[number_of_recent_gcs()]);
ysr@777 2101 }
ysr@777 2102 res = MAX2(res, latest);
ysr@777 2103 res = MAX2(res, min_survival_rate);
ysr@777 2104 // In the parallel case, LAB fragmentation can produce "negative
ysr@777 2105 // collections"; so can evac failure. Cap at 1.0
ysr@777 2106 res = MIN2(res, 1.0);
ysr@777 2107 return res;
ysr@777 2108 }
ysr@777 2109
ysr@777 2110 size_t G1CollectorPolicy::expansion_amount() {
tonyp@3114 2111 double recent_gc_overhead = recent_avg_pause_time_ratio() * 100.0;
tonyp@3114 2112 double threshold = _gc_overhead_perc;
tonyp@3114 2113 if (recent_gc_overhead > threshold) {
johnc@1186 2114 // We will double the existing space, or take
johnc@1186 2115 // G1ExpandByPercentOfAvailable % of the available expansion
johnc@1186 2116 // space, whichever is smaller, bounded below by a minimum
johnc@1186 2117 // expansion (unless that's all that's left.)
ysr@777 2118 const size_t min_expand_bytes = 1*M;
johnc@2504 2119 size_t reserved_bytes = _g1->max_capacity();
ysr@777 2120 size_t committed_bytes = _g1->capacity();
ysr@777 2121 size_t uncommitted_bytes = reserved_bytes - committed_bytes;
ysr@777 2122 size_t expand_bytes;
ysr@777 2123 size_t expand_bytes_via_pct =
johnc@1186 2124 uncommitted_bytes * G1ExpandByPercentOfAvailable / 100;
ysr@777 2125 expand_bytes = MIN2(expand_bytes_via_pct, committed_bytes);
ysr@777 2126 expand_bytes = MAX2(expand_bytes, min_expand_bytes);
ysr@777 2127 expand_bytes = MIN2(expand_bytes, uncommitted_bytes);
tonyp@3114 2128
tonyp@3114 2129 ergo_verbose5(ErgoHeapSizing,
tonyp@3114 2130 "attempt heap expansion",
tonyp@3114 2131 ergo_format_reason("recent GC overhead higher than "
tonyp@3114 2132 "threshold after GC")
tonyp@3114 2133 ergo_format_perc("recent GC overhead")
tonyp@3114 2134 ergo_format_perc("threshold")
tonyp@3114 2135 ergo_format_byte("uncommitted")
tonyp@3114 2136 ergo_format_byte_perc("calculated expansion amount"),
tonyp@3114 2137 recent_gc_overhead, threshold,
tonyp@3114 2138 uncommitted_bytes,
tonyp@3114 2139 expand_bytes_via_pct, (double) G1ExpandByPercentOfAvailable);
tonyp@3114 2140
ysr@777 2141 return expand_bytes;
ysr@777 2142 } else {
ysr@777 2143 return 0;
ysr@777 2144 }
ysr@777 2145 }
ysr@777 2146
ysr@777 2147 void G1CollectorPolicy::note_start_of_mark_thread() {
ysr@777 2148 _mark_thread_startup_sec = os::elapsedTime();
ysr@777 2149 }
ysr@777 2150
ysr@777 2151 class CountCSClosure: public HeapRegionClosure {
ysr@777 2152 G1CollectorPolicy* _g1_policy;
ysr@777 2153 public:
ysr@777 2154 CountCSClosure(G1CollectorPolicy* g1_policy) :
ysr@777 2155 _g1_policy(g1_policy) {}
ysr@777 2156 bool doHeapRegion(HeapRegion* r) {
ysr@777 2157 _g1_policy->_bytes_in_collection_set_before_gc += r->used();
ysr@777 2158 return false;
ysr@777 2159 }
ysr@777 2160 };
ysr@777 2161
ysr@777 2162 void G1CollectorPolicy::count_CS_bytes_used() {
ysr@777 2163 CountCSClosure cs_closure(this);
ysr@777 2164 _g1->collection_set_iterate(&cs_closure);
ysr@777 2165 }
ysr@777 2166
ysr@777 2167 void G1CollectorPolicy::print_summary (int level,
ysr@777 2168 const char* str,
ysr@777 2169 NumberSeq* seq) const {
ysr@777 2170 double sum = seq->sum();
brutisso@2645 2171 LineBuffer(level + 1).append_and_print_cr("%-24s = %8.2lf s (avg = %8.2lf ms)",
ysr@777 2172 str, sum / 1000.0, seq->avg());
ysr@777 2173 }
ysr@777 2174
ysr@777 2175 void G1CollectorPolicy::print_summary_sd (int level,
ysr@777 2176 const char* str,
ysr@777 2177 NumberSeq* seq) const {
ysr@777 2178 print_summary(level, str, seq);
brutisso@2645 2179 LineBuffer(level + 6).append_and_print_cr("(num = %5d, std dev = %8.2lf ms, max = %8.2lf ms)",
ysr@777 2180 seq->num(), seq->sd(), seq->maximum());
ysr@777 2181 }
ysr@777 2182
ysr@777 2183 void G1CollectorPolicy::check_other_times(int level,
ysr@777 2184 NumberSeq* other_times_ms,
ysr@777 2185 NumberSeq* calc_other_times_ms) const {
ysr@777 2186 bool should_print = false;
brutisso@2645 2187 LineBuffer buf(level + 2);
ysr@777 2188
ysr@777 2189 double max_sum = MAX2(fabs(other_times_ms->sum()),
ysr@777 2190 fabs(calc_other_times_ms->sum()));
ysr@777 2191 double min_sum = MIN2(fabs(other_times_ms->sum()),
ysr@777 2192 fabs(calc_other_times_ms->sum()));
ysr@777 2193 double sum_ratio = max_sum / min_sum;
ysr@777 2194 if (sum_ratio > 1.1) {
ysr@777 2195 should_print = true;
brutisso@2645 2196 buf.append_and_print_cr("## CALCULATED OTHER SUM DOESN'T MATCH RECORDED ###");
ysr@777 2197 }
ysr@777 2198
ysr@777 2199 double max_avg = MAX2(fabs(other_times_ms->avg()),
ysr@777 2200 fabs(calc_other_times_ms->avg()));
ysr@777 2201 double min_avg = MIN2(fabs(other_times_ms->avg()),
ysr@777 2202 fabs(calc_other_times_ms->avg()));
ysr@777 2203 double avg_ratio = max_avg / min_avg;
ysr@777 2204 if (avg_ratio > 1.1) {
ysr@777 2205 should_print = true;
brutisso@2645 2206 buf.append_and_print_cr("## CALCULATED OTHER AVG DOESN'T MATCH RECORDED ###");
ysr@777 2207 }
ysr@777 2208
ysr@777 2209 if (other_times_ms->sum() < -0.01) {
brutisso@2645 2210 buf.append_and_print_cr("## RECORDED OTHER SUM IS NEGATIVE ###");
ysr@777 2211 }
ysr@777 2212
ysr@777 2213 if (other_times_ms->avg() < -0.01) {
brutisso@2645 2214 buf.append_and_print_cr("## RECORDED OTHER AVG IS NEGATIVE ###");
ysr@777 2215 }
ysr@777 2216
ysr@777 2217 if (calc_other_times_ms->sum() < -0.01) {
ysr@777 2218 should_print = true;
brutisso@2645 2219 buf.append_and_print_cr("## CALCULATED OTHER SUM IS NEGATIVE ###");
ysr@777 2220 }
ysr@777 2221
ysr@777 2222 if (calc_other_times_ms->avg() < -0.01) {
ysr@777 2223 should_print = true;
brutisso@2645 2224 buf.append_and_print_cr("## CALCULATED OTHER AVG IS NEGATIVE ###");
ysr@777 2225 }
ysr@777 2226
ysr@777 2227 if (should_print)
ysr@777 2228 print_summary(level, "Other(Calc)", calc_other_times_ms);
ysr@777 2229 }
ysr@777 2230
ysr@777 2231 void G1CollectorPolicy::print_summary(PauseSummary* summary) const {
jmasa@2188 2232 bool parallel = G1CollectedHeap::use_parallel_gc_threads();
ysr@777 2233 MainBodySummary* body_summary = summary->main_body_summary();
ysr@777 2234 if (summary->get_total_seq()->num() > 0) {
apetrusenko@1112 2235 print_summary_sd(0, "Evacuation Pauses", summary->get_total_seq());
ysr@777 2236 if (body_summary != NULL) {
ysr@777 2237 print_summary(1, "SATB Drain", body_summary->get_satb_drain_seq());
ysr@777 2238 if (parallel) {
ysr@777 2239 print_summary(1, "Parallel Time", body_summary->get_parallel_seq());
ysr@777 2240 print_summary(2, "Update RS", body_summary->get_update_rs_seq());
ysr@777 2241 print_summary(2, "Ext Root Scanning",
ysr@777 2242 body_summary->get_ext_root_scan_seq());
ysr@777 2243 print_summary(2, "Mark Stack Scanning",
ysr@777 2244 body_summary->get_mark_stack_scan_seq());
ysr@777 2245 print_summary(2, "Scan RS", body_summary->get_scan_rs_seq());
ysr@777 2246 print_summary(2, "Object Copy", body_summary->get_obj_copy_seq());
ysr@777 2247 print_summary(2, "Termination", body_summary->get_termination_seq());
ysr@777 2248 print_summary(2, "Other", body_summary->get_parallel_other_seq());
ysr@777 2249 {
ysr@777 2250 NumberSeq* other_parts[] = {
ysr@777 2251 body_summary->get_update_rs_seq(),
ysr@777 2252 body_summary->get_ext_root_scan_seq(),
ysr@777 2253 body_summary->get_mark_stack_scan_seq(),
ysr@777 2254 body_summary->get_scan_rs_seq(),
ysr@777 2255 body_summary->get_obj_copy_seq(),
ysr@777 2256 body_summary->get_termination_seq()
ysr@777 2257 };
ysr@777 2258 NumberSeq calc_other_times_ms(body_summary->get_parallel_seq(),
johnc@2134 2259 6, other_parts);
ysr@777 2260 check_other_times(2, body_summary->get_parallel_other_seq(),
ysr@777 2261 &calc_other_times_ms);
ysr@777 2262 }
ysr@777 2263 print_summary(1, "Mark Closure", body_summary->get_mark_closure_seq());
ysr@777 2264 print_summary(1, "Clear CT", body_summary->get_clear_ct_seq());
ysr@777 2265 } else {
ysr@777 2266 print_summary(1, "Update RS", body_summary->get_update_rs_seq());
ysr@777 2267 print_summary(1, "Ext Root Scanning",
ysr@777 2268 body_summary->get_ext_root_scan_seq());
ysr@777 2269 print_summary(1, "Mark Stack Scanning",
ysr@777 2270 body_summary->get_mark_stack_scan_seq());
ysr@777 2271 print_summary(1, "Scan RS", body_summary->get_scan_rs_seq());
ysr@777 2272 print_summary(1, "Object Copy", body_summary->get_obj_copy_seq());
ysr@777 2273 }
ysr@777 2274 }
ysr@777 2275 print_summary(1, "Other", summary->get_other_seq());
ysr@777 2276 {
johnc@2134 2277 if (body_summary != NULL) {
johnc@2134 2278 NumberSeq calc_other_times_ms;
johnc@2134 2279 if (parallel) {
johnc@2134 2280 // parallel
johnc@2134 2281 NumberSeq* other_parts[] = {
johnc@2134 2282 body_summary->get_satb_drain_seq(),
johnc@2134 2283 body_summary->get_parallel_seq(),
johnc@2134 2284 body_summary->get_clear_ct_seq()
johnc@2134 2285 };
johnc@2134 2286 calc_other_times_ms = NumberSeq(summary->get_total_seq(),
johnc@2134 2287 3, other_parts);
johnc@2134 2288 } else {
johnc@2134 2289 // serial
johnc@2134 2290 NumberSeq* other_parts[] = {
johnc@2134 2291 body_summary->get_satb_drain_seq(),
johnc@2134 2292 body_summary->get_update_rs_seq(),
johnc@2134 2293 body_summary->get_ext_root_scan_seq(),
johnc@2134 2294 body_summary->get_mark_stack_scan_seq(),
johnc@2134 2295 body_summary->get_scan_rs_seq(),
johnc@2134 2296 body_summary->get_obj_copy_seq()
johnc@2134 2297 };
johnc@2134 2298 calc_other_times_ms = NumberSeq(summary->get_total_seq(),
johnc@2134 2299 6, other_parts);
johnc@2134 2300 }
johnc@2134 2301 check_other_times(1, summary->get_other_seq(), &calc_other_times_ms);
ysr@777 2302 }
ysr@777 2303 }
ysr@777 2304 } else {
brutisso@2645 2305 LineBuffer(1).append_and_print_cr("none");
ysr@777 2306 }
brutisso@2645 2307 LineBuffer(0).append_and_print_cr("");
ysr@777 2308 }
ysr@777 2309
ysr@777 2310 void G1CollectorPolicy::print_tracing_info() const {
ysr@777 2311 if (TraceGen0Time) {
ysr@777 2312 gclog_or_tty->print_cr("ALL PAUSES");
ysr@777 2313 print_summary_sd(0, "Total", _all_pause_times_ms);
ysr@777 2314 gclog_or_tty->print_cr("");
ysr@777 2315 gclog_or_tty->print_cr("");
ysr@777 2316 gclog_or_tty->print_cr(" Full Young GC Pauses: %8d", _full_young_pause_num);
ysr@777 2317 gclog_or_tty->print_cr(" Partial Young GC Pauses: %8d", _partial_young_pause_num);
ysr@777 2318 gclog_or_tty->print_cr("");
ysr@777 2319
apetrusenko@1112 2320 gclog_or_tty->print_cr("EVACUATION PAUSES");
apetrusenko@1112 2321 print_summary(_summary);
ysr@777 2322
ysr@777 2323 gclog_or_tty->print_cr("MISC");
ysr@777 2324 print_summary_sd(0, "Stop World", _all_stop_world_times_ms);
ysr@777 2325 print_summary_sd(0, "Yields", _all_yield_times_ms);
ysr@777 2326 for (int i = 0; i < _aux_num; ++i) {
ysr@777 2327 if (_all_aux_times_ms[i].num() > 0) {
ysr@777 2328 char buffer[96];
ysr@777 2329 sprintf(buffer, "Aux%d", i);
ysr@777 2330 print_summary_sd(0, buffer, &_all_aux_times_ms[i]);
ysr@777 2331 }
ysr@777 2332 }
ysr@777 2333
ysr@777 2334 size_t all_region_num = _region_num_young + _region_num_tenured;
ysr@777 2335 gclog_or_tty->print_cr(" New Regions %8d, Young %8d (%6.2lf%%), "
ysr@777 2336 "Tenured %8d (%6.2lf%%)",
ysr@777 2337 all_region_num,
ysr@777 2338 _region_num_young,
ysr@777 2339 (double) _region_num_young / (double) all_region_num * 100.0,
ysr@777 2340 _region_num_tenured,
ysr@777 2341 (double) _region_num_tenured / (double) all_region_num * 100.0);
ysr@777 2342 }
ysr@777 2343 if (TraceGen1Time) {
ysr@777 2344 if (_all_full_gc_times_ms->num() > 0) {
ysr@777 2345 gclog_or_tty->print("\n%4d full_gcs: total time = %8.2f s",
ysr@777 2346 _all_full_gc_times_ms->num(),
ysr@777 2347 _all_full_gc_times_ms->sum() / 1000.0);
ysr@777 2348 gclog_or_tty->print_cr(" (avg = %8.2fms).", _all_full_gc_times_ms->avg());
ysr@777 2349 gclog_or_tty->print_cr(" [std. dev = %8.2f ms, max = %8.2f ms]",
ysr@777 2350 _all_full_gc_times_ms->sd(),
ysr@777 2351 _all_full_gc_times_ms->maximum());
ysr@777 2352 }
ysr@777 2353 }
ysr@777 2354 }
ysr@777 2355
ysr@777 2356 void G1CollectorPolicy::print_yg_surv_rate_info() const {
ysr@777 2357 #ifndef PRODUCT
ysr@777 2358 _short_lived_surv_rate_group->print_surv_rate_summary();
ysr@777 2359 // add this call for any other surv rate groups
ysr@777 2360 #endif // PRODUCT
ysr@777 2361 }
ysr@777 2362
tonyp@3114 2363 void G1CollectorPolicy::update_region_num(bool young) {
tonyp@2315 2364 if (young) {
ysr@777 2365 ++_region_num_young;
ysr@777 2366 } else {
ysr@777 2367 ++_region_num_tenured;
ysr@777 2368 }
ysr@777 2369 }
ysr@777 2370
ysr@777 2371 #ifndef PRODUCT
ysr@777 2372 // for debugging, bit of a hack...
ysr@777 2373 static char*
ysr@777 2374 region_num_to_mbs(int length) {
ysr@777 2375 static char buffer[64];
ysr@777 2376 double bytes = (double) (length * HeapRegion::GrainBytes);
ysr@777 2377 double mbs = bytes / (double) (1024 * 1024);
ysr@777 2378 sprintf(buffer, "%7.2lfMB", mbs);
ysr@777 2379 return buffer;
ysr@777 2380 }
ysr@777 2381 #endif // PRODUCT
ysr@777 2382
apetrusenko@980 2383 size_t G1CollectorPolicy::max_regions(int purpose) {
ysr@777 2384 switch (purpose) {
ysr@777 2385 case GCAllocForSurvived:
apetrusenko@980 2386 return _max_survivor_regions;
ysr@777 2387 case GCAllocForTenured:
apetrusenko@980 2388 return REGIONS_UNLIMITED;
ysr@777 2389 default:
apetrusenko@980 2390 ShouldNotReachHere();
apetrusenko@980 2391 return REGIONS_UNLIMITED;
ysr@777 2392 };
ysr@777 2393 }
ysr@777 2394
tonyp@3119 2395 void G1CollectorPolicy::update_max_gc_locker_expansion() {
tonyp@2333 2396 size_t expansion_region_num = 0;
tonyp@2333 2397 if (GCLockerEdenExpansionPercent > 0) {
tonyp@2333 2398 double perc = (double) GCLockerEdenExpansionPercent / 100.0;
tonyp@2333 2399 double expansion_region_num_d = perc * (double) _young_list_target_length;
tonyp@2333 2400 // We use ceiling so that if expansion_region_num_d is > 0.0 (but
tonyp@2333 2401 // less than 1.0) we'll get 1.
tonyp@2333 2402 expansion_region_num = (size_t) ceil(expansion_region_num_d);
tonyp@2333 2403 } else {
tonyp@2333 2404 assert(expansion_region_num == 0, "sanity");
tonyp@2333 2405 }
tonyp@2333 2406 _young_list_max_length = _young_list_target_length + expansion_region_num;
tonyp@2333 2407 assert(_young_list_target_length <= _young_list_max_length, "post-condition");
tonyp@2333 2408 }
tonyp@2333 2409
apetrusenko@980 2410 // Calculates survivor space parameters.
tonyp@3119 2411 void G1CollectorPolicy::update_survivors_policy() {
tonyp@3119 2412 double max_survivor_regions_d =
tonyp@3119 2413 (double) _young_list_target_length / (double) SurvivorRatio;
tonyp@3119 2414 // We use ceiling so that if max_survivor_regions_d is > 0.0 (but
tonyp@3119 2415 // smaller than 1.0) we'll get 1.
tonyp@3119 2416 _max_survivor_regions = (size_t) ceil(max_survivor_regions_d);
tonyp@3119 2417
tonyp@3066 2418 _tenuring_threshold = _survivors_age_table.compute_tenuring_threshold(
apetrusenko@980 2419 HeapRegion::GrainWords * _max_survivor_regions);
apetrusenko@980 2420 }
apetrusenko@980 2421
ysr@777 2422 #ifndef PRODUCT
ysr@777 2423 class HRSortIndexIsOKClosure: public HeapRegionClosure {
ysr@777 2424 CollectionSetChooser* _chooser;
ysr@777 2425 public:
ysr@777 2426 HRSortIndexIsOKClosure(CollectionSetChooser* chooser) :
ysr@777 2427 _chooser(chooser) {}
ysr@777 2428
ysr@777 2429 bool doHeapRegion(HeapRegion* r) {
ysr@777 2430 if (!r->continuesHumongous()) {
ysr@777 2431 assert(_chooser->regionProperlyOrdered(r), "Ought to be.");
ysr@777 2432 }
ysr@777 2433 return false;
ysr@777 2434 }
ysr@777 2435 };
ysr@777 2436
ysr@777 2437 bool G1CollectorPolicy_BestRegionsFirst::assertMarkedBytesDataOK() {
ysr@777 2438 HRSortIndexIsOKClosure cl(_collectionSetChooser);
ysr@777 2439 _g1->heap_region_iterate(&cl);
ysr@777 2440 return true;
ysr@777 2441 }
ysr@777 2442 #endif
ysr@777 2443
tonyp@3114 2444 bool G1CollectorPolicy::force_initial_mark_if_outside_cycle(
tonyp@3114 2445 GCCause::Cause gc_cause) {
tonyp@2011 2446 bool during_cycle = _g1->concurrent_mark()->cmThread()->during_cycle();
tonyp@2011 2447 if (!during_cycle) {
tonyp@3114 2448 ergo_verbose1(ErgoConcCycles,
tonyp@3114 2449 "request concurrent cycle initiation",
tonyp@3114 2450 ergo_format_reason("requested by GC cause")
tonyp@3114 2451 ergo_format_str("GC cause"),
tonyp@3114 2452 GCCause::to_string(gc_cause));
tonyp@2011 2453 set_initiate_conc_mark_if_possible();
tonyp@2011 2454 return true;
tonyp@2011 2455 } else {
tonyp@3114 2456 ergo_verbose1(ErgoConcCycles,
tonyp@3114 2457 "do not request concurrent cycle initiation",
tonyp@3114 2458 ergo_format_reason("concurrent cycle already in progress")
tonyp@3114 2459 ergo_format_str("GC cause"),
tonyp@3114 2460 GCCause::to_string(gc_cause));
tonyp@2011 2461 return false;
tonyp@2011 2462 }
tonyp@2011 2463 }
tonyp@2011 2464
ysr@777 2465 void
tonyp@1794 2466 G1CollectorPolicy::decide_on_conc_mark_initiation() {
tonyp@1794 2467 // We are about to decide on whether this pause will be an
tonyp@1794 2468 // initial-mark pause.
tonyp@1794 2469
tonyp@1794 2470 // First, during_initial_mark_pause() should not be already set. We
tonyp@1794 2471 // will set it here if we have to. However, it should be cleared by
tonyp@1794 2472 // the end of the pause (it's only set for the duration of an
tonyp@1794 2473 // initial-mark pause).
tonyp@1794 2474 assert(!during_initial_mark_pause(), "pre-condition");
tonyp@1794 2475
tonyp@1794 2476 if (initiate_conc_mark_if_possible()) {
tonyp@1794 2477 // We had noticed on a previous pause that the heap occupancy has
tonyp@1794 2478 // gone over the initiating threshold and we should start a
tonyp@1794 2479 // concurrent marking cycle. So we might initiate one.
tonyp@1794 2480
tonyp@1794 2481 bool during_cycle = _g1->concurrent_mark()->cmThread()->during_cycle();
tonyp@1794 2482 if (!during_cycle) {
tonyp@1794 2483 // The concurrent marking thread is not "during a cycle", i.e.,
tonyp@1794 2484 // it has completed the last one. So we can go ahead and
tonyp@1794 2485 // initiate a new cycle.
tonyp@1794 2486
tonyp@1794 2487 set_during_initial_mark_pause();
tonyp@1794 2488
tonyp@1794 2489 // And we can now clear initiate_conc_mark_if_possible() as
tonyp@1794 2490 // we've already acted on it.
tonyp@1794 2491 clear_initiate_conc_mark_if_possible();
tonyp@3114 2492
tonyp@3114 2493 ergo_verbose0(ErgoConcCycles,
tonyp@3114 2494 "initiate concurrent cycle",
tonyp@3114 2495 ergo_format_reason("concurrent cycle initiation requested"));
tonyp@1794 2496 } else {
tonyp@1794 2497 // The concurrent marking thread is still finishing up the
tonyp@1794 2498 // previous cycle. If we start one right now the two cycles
tonyp@1794 2499 // overlap. In particular, the concurrent marking thread might
tonyp@1794 2500 // be in the process of clearing the next marking bitmap (which
tonyp@1794 2501 // we will use for the next cycle if we start one). Starting a
tonyp@1794 2502 // cycle now will be bad given that parts of the marking
tonyp@1794 2503 // information might get cleared by the marking thread. And we
tonyp@1794 2504 // cannot wait for the marking thread to finish the cycle as it
tonyp@1794 2505 // periodically yields while clearing the next marking bitmap
tonyp@1794 2506 // and, if it's in a yield point, it's waiting for us to
tonyp@1794 2507 // finish. So, at this point we will not start a cycle and we'll
tonyp@1794 2508 // let the concurrent marking thread complete the last one.
tonyp@3114 2509 ergo_verbose0(ErgoConcCycles,
tonyp@3114 2510 "do not initiate concurrent cycle",
tonyp@3114 2511 ergo_format_reason("concurrent cycle already in progress"));
tonyp@1794 2512 }
tonyp@1794 2513 }
tonyp@1794 2514 }
tonyp@1794 2515
tonyp@1794 2516 void
ysr@777 2517 G1CollectorPolicy_BestRegionsFirst::
ysr@777 2518 record_collection_pause_start(double start_time_sec, size_t start_used) {
ysr@777 2519 G1CollectorPolicy::record_collection_pause_start(start_time_sec, start_used);
ysr@777 2520 }
ysr@777 2521
ysr@777 2522 class KnownGarbageClosure: public HeapRegionClosure {
ysr@777 2523 CollectionSetChooser* _hrSorted;
ysr@777 2524
ysr@777 2525 public:
ysr@777 2526 KnownGarbageClosure(CollectionSetChooser* hrSorted) :
ysr@777 2527 _hrSorted(hrSorted)
ysr@777 2528 {}
ysr@777 2529
ysr@777 2530 bool doHeapRegion(HeapRegion* r) {
ysr@777 2531 // We only include humongous regions in collection
ysr@777 2532 // sets when concurrent mark shows that their contained object is
ysr@777 2533 // unreachable.
ysr@777 2534
ysr@777 2535 // Do we have any marking information for this region?
ysr@777 2536 if (r->is_marked()) {
ysr@777 2537 // We don't include humongous regions in collection
ysr@777 2538 // sets because we collect them immediately at the end of a marking
ysr@777 2539 // cycle. We also don't include young regions because we *must*
ysr@777 2540 // include them in the next collection pause.
ysr@777 2541 if (!r->isHumongous() && !r->is_young()) {
ysr@777 2542 _hrSorted->addMarkedHeapRegion(r);
ysr@777 2543 }
ysr@777 2544 }
ysr@777 2545 return false;
ysr@777 2546 }
ysr@777 2547 };
ysr@777 2548
ysr@777 2549 class ParKnownGarbageHRClosure: public HeapRegionClosure {
ysr@777 2550 CollectionSetChooser* _hrSorted;
ysr@777 2551 jint _marked_regions_added;
ysr@777 2552 jint _chunk_size;
ysr@777 2553 jint _cur_chunk_idx;
ysr@777 2554 jint _cur_chunk_end; // Cur chunk [_cur_chunk_idx, _cur_chunk_end)
ysr@777 2555 int _worker;
ysr@777 2556 int _invokes;
ysr@777 2557
ysr@777 2558 void get_new_chunk() {
ysr@777 2559 _cur_chunk_idx = _hrSorted->getParMarkedHeapRegionChunk(_chunk_size);
ysr@777 2560 _cur_chunk_end = _cur_chunk_idx + _chunk_size;
ysr@777 2561 }
ysr@777 2562 void add_region(HeapRegion* r) {
ysr@777 2563 if (_cur_chunk_idx == _cur_chunk_end) {
ysr@777 2564 get_new_chunk();
ysr@777 2565 }
ysr@777 2566 assert(_cur_chunk_idx < _cur_chunk_end, "postcondition");
ysr@777 2567 _hrSorted->setMarkedHeapRegion(_cur_chunk_idx, r);
ysr@777 2568 _marked_regions_added++;
ysr@777 2569 _cur_chunk_idx++;
ysr@777 2570 }
ysr@777 2571
ysr@777 2572 public:
ysr@777 2573 ParKnownGarbageHRClosure(CollectionSetChooser* hrSorted,
ysr@777 2574 jint chunk_size,
ysr@777 2575 int worker) :
ysr@777 2576 _hrSorted(hrSorted), _chunk_size(chunk_size), _worker(worker),
ysr@777 2577 _marked_regions_added(0), _cur_chunk_idx(0), _cur_chunk_end(0),
ysr@777 2578 _invokes(0)
ysr@777 2579 {}
ysr@777 2580
ysr@777 2581 bool doHeapRegion(HeapRegion* r) {
ysr@777 2582 // We only include humongous regions in collection
ysr@777 2583 // sets when concurrent mark shows that their contained object is
ysr@777 2584 // unreachable.
ysr@777 2585 _invokes++;
ysr@777 2586
ysr@777 2587 // Do we have any marking information for this region?
ysr@777 2588 if (r->is_marked()) {
ysr@777 2589 // We don't include humongous regions in collection
ysr@777 2590 // sets because we collect them immediately at the end of a marking
ysr@777 2591 // cycle.
ysr@777 2592 // We also do not include young regions in collection sets
ysr@777 2593 if (!r->isHumongous() && !r->is_young()) {
ysr@777 2594 add_region(r);
ysr@777 2595 }
ysr@777 2596 }
ysr@777 2597 return false;
ysr@777 2598 }
ysr@777 2599 jint marked_regions_added() { return _marked_regions_added; }
ysr@777 2600 int invokes() { return _invokes; }
ysr@777 2601 };
ysr@777 2602
ysr@777 2603 class ParKnownGarbageTask: public AbstractGangTask {
ysr@777 2604 CollectionSetChooser* _hrSorted;
ysr@777 2605 jint _chunk_size;
ysr@777 2606 G1CollectedHeap* _g1;
ysr@777 2607 public:
ysr@777 2608 ParKnownGarbageTask(CollectionSetChooser* hrSorted, jint chunk_size) :
ysr@777 2609 AbstractGangTask("ParKnownGarbageTask"),
ysr@777 2610 _hrSorted(hrSorted), _chunk_size(chunk_size),
ysr@777 2611 _g1(G1CollectedHeap::heap())
ysr@777 2612 {}
ysr@777 2613
ysr@777 2614 void work(int i) {
ysr@777 2615 ParKnownGarbageHRClosure parKnownGarbageCl(_hrSorted, _chunk_size, i);
ysr@777 2616 // Back to zero for the claim value.
tonyp@790 2617 _g1->heap_region_par_iterate_chunked(&parKnownGarbageCl, i,
tonyp@790 2618 HeapRegion::InitialClaimValue);
ysr@777 2619 jint regions_added = parKnownGarbageCl.marked_regions_added();
ysr@777 2620 _hrSorted->incNumMarkedHeapRegions(regions_added);
ysr@777 2621 if (G1PrintParCleanupStats) {
brutisso@2645 2622 gclog_or_tty->print_cr(" Thread %d called %d times, added %d regions to list.",
ysr@777 2623 i, parKnownGarbageCl.invokes(), regions_added);
ysr@777 2624 }
ysr@777 2625 }
ysr@777 2626 };
ysr@777 2627
ysr@777 2628 void
ysr@777 2629 G1CollectorPolicy_BestRegionsFirst::
ysr@777 2630 record_concurrent_mark_cleanup_end(size_t freed_bytes,
ysr@777 2631 size_t max_live_bytes) {
ysr@777 2632 double start;
ysr@777 2633 if (G1PrintParCleanupStats) start = os::elapsedTime();
ysr@777 2634 record_concurrent_mark_cleanup_end_work1(freed_bytes, max_live_bytes);
ysr@777 2635
ysr@777 2636 _collectionSetChooser->clearMarkedHeapRegions();
ysr@777 2637 double clear_marked_end;
ysr@777 2638 if (G1PrintParCleanupStats) {
ysr@777 2639 clear_marked_end = os::elapsedTime();
ysr@777 2640 gclog_or_tty->print_cr(" clear marked regions + work1: %8.3f ms.",
ysr@777 2641 (clear_marked_end - start)*1000.0);
ysr@777 2642 }
jmasa@2188 2643 if (G1CollectedHeap::use_parallel_gc_threads()) {
ysr@777 2644 const size_t OverpartitionFactor = 4;
kvn@1926 2645 const size_t MinWorkUnit = 8;
kvn@1926 2646 const size_t WorkUnit =
ysr@777 2647 MAX2(_g1->n_regions() / (ParallelGCThreads * OverpartitionFactor),
kvn@1926 2648 MinWorkUnit);
ysr@777 2649 _collectionSetChooser->prepareForAddMarkedHeapRegionsPar(_g1->n_regions(),
kvn@1926 2650 WorkUnit);
ysr@777 2651 ParKnownGarbageTask parKnownGarbageTask(_collectionSetChooser,
kvn@1926 2652 (int) WorkUnit);
ysr@777 2653 _g1->workers()->run_task(&parKnownGarbageTask);
tonyp@790 2654
tonyp@790 2655 assert(_g1->check_heap_region_claim_values(HeapRegion::InitialClaimValue),
tonyp@790 2656 "sanity check");
ysr@777 2657 } else {
ysr@777 2658 KnownGarbageClosure knownGarbagecl(_collectionSetChooser);
ysr@777 2659 _g1->heap_region_iterate(&knownGarbagecl);
ysr@777 2660 }
ysr@777 2661 double known_garbage_end;
ysr@777 2662 if (G1PrintParCleanupStats) {
ysr@777 2663 known_garbage_end = os::elapsedTime();
ysr@777 2664 gclog_or_tty->print_cr(" compute known garbage: %8.3f ms.",
ysr@777 2665 (known_garbage_end - clear_marked_end)*1000.0);
ysr@777 2666 }
ysr@777 2667 _collectionSetChooser->sortMarkedHeapRegions();
ysr@777 2668 double sort_end;
ysr@777 2669 if (G1PrintParCleanupStats) {
ysr@777 2670 sort_end = os::elapsedTime();
ysr@777 2671 gclog_or_tty->print_cr(" sorting: %8.3f ms.",
ysr@777 2672 (sort_end - known_garbage_end)*1000.0);
ysr@777 2673 }
ysr@777 2674
ysr@777 2675 record_concurrent_mark_cleanup_end_work2();
ysr@777 2676 double work2_end;
ysr@777 2677 if (G1PrintParCleanupStats) {
ysr@777 2678 work2_end = os::elapsedTime();
ysr@777 2679 gclog_or_tty->print_cr(" work2: %8.3f ms.",
ysr@777 2680 (work2_end - sort_end)*1000.0);
ysr@777 2681 }
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@2062 2896 void
tonyp@2011 2897 G1CollectorPolicy_BestRegionsFirst::choose_collection_set(
tonyp@2011 2898 double target_pause_time_ms) {
johnc@1829 2899 // Set this here - in case we're not doing young collections.
johnc@1829 2900 double non_young_start_time_sec = os::elapsedTime();
johnc@1829 2901
tonyp@3114 2902 YoungList* young_list = _g1->young_list();
tonyp@3114 2903
ysr@777 2904 start_recording_regions();
ysr@777 2905
tonyp@2011 2906 guarantee(target_pause_time_ms > 0.0,
tonyp@2011 2907 err_msg("target_pause_time_ms = %1.6lf should be positive",
tonyp@2011 2908 target_pause_time_ms));
tonyp@2011 2909 guarantee(_collection_set == NULL, "Precondition");
ysr@777 2910
ysr@777 2911 double base_time_ms = predict_base_elapsed_time_ms(_pending_cards);
ysr@777 2912 double predicted_pause_time_ms = base_time_ms;
ysr@777 2913
tonyp@2011 2914 double time_remaining_ms = target_pause_time_ms - base_time_ms;
ysr@777 2915
tonyp@3114 2916 ergo_verbose3(ErgoCSetConstruction | ErgoHigh,
tonyp@3114 2917 "start choosing CSet",
tonyp@3114 2918 ergo_format_ms("predicted base time")
tonyp@3114 2919 ergo_format_ms("remaining time")
tonyp@3114 2920 ergo_format_ms("target pause time"),
tonyp@3114 2921 base_time_ms, time_remaining_ms, target_pause_time_ms);
tonyp@3114 2922
ysr@777 2923 // the 10% and 50% values are arbitrary...
tonyp@3114 2924 double threshold = 0.10 * target_pause_time_ms;
tonyp@3114 2925 if (time_remaining_ms < threshold) {
tonyp@3114 2926 double prev_time_remaining_ms = time_remaining_ms;
tonyp@2011 2927 time_remaining_ms = 0.50 * target_pause_time_ms;
ysr@777 2928 _within_target = false;
tonyp@3114 2929 ergo_verbose3(ErgoCSetConstruction,
tonyp@3114 2930 "adjust remaining time",
tonyp@3114 2931 ergo_format_reason("remaining time lower than threshold")
tonyp@3114 2932 ergo_format_ms("remaining time")
tonyp@3114 2933 ergo_format_ms("threshold")
tonyp@3114 2934 ergo_format_ms("adjusted remaining time"),
tonyp@3114 2935 prev_time_remaining_ms, threshold, time_remaining_ms);
ysr@777 2936 } else {
ysr@777 2937 _within_target = true;
ysr@777 2938 }
ysr@777 2939
tonyp@3114 2940 size_t expansion_bytes = _g1->expansion_regions() * HeapRegion::GrainBytes;
tonyp@3114 2941
tonyp@3114 2942 HeapRegion* hr;
tonyp@3114 2943 double young_start_time_sec = os::elapsedTime();
ysr@777 2944
apetrusenko@1112 2945 _collection_set_bytes_used_before = 0;
apetrusenko@1112 2946 _collection_set_size = 0;
brutisso@3065 2947 _young_cset_length = 0;
brutisso@3065 2948 _last_young_gc_full = full_young_gcs() ? true : false;
brutisso@3065 2949
tonyp@3114 2950 if (_last_young_gc_full) {
brutisso@3065 2951 ++_full_young_pause_num;
tonyp@3114 2952 } else {
brutisso@3065 2953 ++_partial_young_pause_num;
tonyp@3114 2954 }
brutisso@3065 2955
brutisso@3065 2956 // The young list is laid with the survivor regions from the previous
brutisso@3065 2957 // pause are appended to the RHS of the young list, i.e.
brutisso@3065 2958 // [Newly Young Regions ++ Survivors from last pause].
brutisso@3065 2959
tonyp@3114 2960 size_t survivor_region_num = young_list->survivor_length();
tonyp@3114 2961 size_t eden_region_num = young_list->length() - survivor_region_num;
tonyp@3114 2962 size_t old_region_num = 0;
tonyp@3114 2963 hr = young_list->first_survivor_region();
brutisso@3065 2964 while (hr != NULL) {
brutisso@3065 2965 assert(hr->is_survivor(), "badly formed young list");
brutisso@3065 2966 hr->set_young();
brutisso@3065 2967 hr = hr->get_next_young_region();
brutisso@3065 2968 }
brutisso@3065 2969
tonyp@3114 2970 // Clear the fields that point to the survivor list - they are all young now.
tonyp@3114 2971 young_list->clear_survivors();
brutisso@3065 2972
brutisso@3065 2973 if (_g1->mark_in_progress())
brutisso@3065 2974 _g1->concurrent_mark()->register_collection_set_finger(_inc_cset_max_finger);
brutisso@3065 2975
brutisso@3065 2976 _young_cset_length = _inc_cset_young_index;
brutisso@3065 2977 _collection_set = _inc_cset_head;
brutisso@3065 2978 _collection_set_size = _inc_cset_size;
brutisso@3065 2979 _collection_set_bytes_used_before = _inc_cset_bytes_used_before;
brutisso@3065 2980 time_remaining_ms -= _inc_cset_predicted_elapsed_time_ms;
brutisso@3065 2981 predicted_pause_time_ms += _inc_cset_predicted_elapsed_time_ms;
brutisso@3065 2982
tonyp@3114 2983 ergo_verbose3(ErgoCSetConstruction | ErgoHigh,
tonyp@3114 2984 "add young regions to CSet",
tonyp@3114 2985 ergo_format_region("eden")
tonyp@3114 2986 ergo_format_region("survivors")
tonyp@3114 2987 ergo_format_ms("predicted young region time"),
tonyp@3114 2988 eden_region_num, survivor_region_num,
tonyp@3114 2989 _inc_cset_predicted_elapsed_time_ms);
tonyp@3114 2990
brutisso@3065 2991 // The number of recorded young regions is the incremental
brutisso@3065 2992 // collection set's current size
brutisso@3065 2993 set_recorded_young_regions(_inc_cset_size);
brutisso@3065 2994 set_recorded_rs_lengths(_inc_cset_recorded_rs_lengths);
brutisso@3065 2995 set_recorded_young_bytes(_inc_cset_recorded_young_bytes);
johnc@1829 2996 #if PREDICTIONS_VERBOSE
brutisso@3065 2997 set_predicted_bytes_to_copy(_inc_cset_predicted_bytes_to_copy);
johnc@1829 2998 #endif // PREDICTIONS_VERBOSE
johnc@1829 2999
tonyp@3114 3000 assert(_inc_cset_size == young_list->length(), "Invariant");
brutisso@3065 3001
brutisso@3065 3002 double young_end_time_sec = os::elapsedTime();
brutisso@3065 3003 _recorded_young_cset_choice_time_ms =
brutisso@3065 3004 (young_end_time_sec - young_start_time_sec) * 1000.0;
brutisso@3065 3005
brutisso@3065 3006 // We are doing young collections so reset this.
brutisso@3065 3007 non_young_start_time_sec = young_end_time_sec;
brutisso@3065 3008
brutisso@3065 3009 if (!full_young_gcs()) {
ysr@777 3010 bool should_continue = true;
ysr@777 3011 NumberSeq seq;
ysr@777 3012 double avg_prediction = 100000000000000000.0; // something very large
johnc@1829 3013
tonyp@3114 3014 size_t prev_collection_set_size = _collection_set_size;
tonyp@3114 3015 double prev_predicted_pause_time_ms = predicted_pause_time_ms;
ysr@777 3016 do {
ysr@777 3017 hr = _collectionSetChooser->getNextMarkedRegion(time_remaining_ms,
ysr@777 3018 avg_prediction);
apetrusenko@1112 3019 if (hr != NULL) {
ysr@777 3020 double predicted_time_ms = predict_region_elapsed_time_ms(hr, false);
ysr@777 3021 time_remaining_ms -= predicted_time_ms;
ysr@777 3022 predicted_pause_time_ms += predicted_time_ms;
ysr@777 3023 add_to_collection_set(hr);
johnc@1829 3024 record_non_young_cset_region(hr);
ysr@777 3025 seq.add(predicted_time_ms);
ysr@777 3026 avg_prediction = seq.avg() + seq.sd();
ysr@777 3027 }
tonyp@3114 3028
tonyp@3114 3029 should_continue = true;
tonyp@3114 3030 if (hr == NULL) {
tonyp@3114 3031 // No need for an ergo verbose message here,
tonyp@3114 3032 // getNextMarkRegion() does this when it returns NULL.
tonyp@3114 3033 should_continue = false;
tonyp@3114 3034 } else {
tonyp@3114 3035 if (adaptive_young_list_length()) {
tonyp@3114 3036 if (time_remaining_ms < 0.0) {
tonyp@3114 3037 ergo_verbose1(ErgoCSetConstruction,
tonyp@3114 3038 "stop adding old regions to CSet",
tonyp@3114 3039 ergo_format_reason("remaining time is lower than 0")
tonyp@3114 3040 ergo_format_ms("remaining time"),
tonyp@3114 3041 time_remaining_ms);
tonyp@3114 3042 should_continue = false;
tonyp@3114 3043 }
tonyp@3114 3044 } else {
tonyp@3126 3045 if (_collection_set_size >= _young_list_fixed_length) {
tonyp@3114 3046 ergo_verbose2(ErgoCSetConstruction,
tonyp@3114 3047 "stop adding old regions to CSet",
tonyp@3126 3048 ergo_format_reason("CSet length reached target")
tonyp@3114 3049 ergo_format_region("CSet")
tonyp@3114 3050 ergo_format_region("young target"),
tonyp@3114 3051 _collection_set_size, _young_list_fixed_length);
tonyp@3114 3052 should_continue = false;
tonyp@3114 3053 }
tonyp@3114 3054 }
tonyp@3114 3055 }
ysr@777 3056 } while (should_continue);
ysr@777 3057
ysr@777 3058 if (!adaptive_young_list_length() &&
tonyp@3114 3059 _collection_set_size < _young_list_fixed_length) {
tonyp@3114 3060 ergo_verbose2(ErgoCSetConstruction,
tonyp@3114 3061 "request partially-young GCs end",
tonyp@3114 3062 ergo_format_reason("CSet length lower than target")
tonyp@3114 3063 ergo_format_region("CSet")
tonyp@3114 3064 ergo_format_region("young target"),
tonyp@3114 3065 _collection_set_size, _young_list_fixed_length);
ysr@777 3066 _should_revert_to_full_young_gcs = true;
tonyp@3114 3067 }
tonyp@3114 3068
tonyp@3114 3069 old_region_num = _collection_set_size - prev_collection_set_size;
tonyp@3114 3070
tonyp@3114 3071 ergo_verbose2(ErgoCSetConstruction | ErgoHigh,
tonyp@3114 3072 "add old regions to CSet",
tonyp@3114 3073 ergo_format_region("old")
tonyp@3114 3074 ergo_format_ms("predicted old region time"),
tonyp@3114 3075 old_region_num,
tonyp@3114 3076 predicted_pause_time_ms - prev_predicted_pause_time_ms);
ysr@777 3077 }
ysr@777 3078
johnc@1829 3079 stop_incremental_cset_building();
johnc@1829 3080
ysr@777 3081 count_CS_bytes_used();
ysr@777 3082
ysr@777 3083 end_recording_regions();
ysr@777 3084
tonyp@3114 3085 ergo_verbose5(ErgoCSetConstruction,
tonyp@3114 3086 "finish choosing CSet",
tonyp@3114 3087 ergo_format_region("eden")
tonyp@3114 3088 ergo_format_region("survivors")
tonyp@3114 3089 ergo_format_region("old")
tonyp@3114 3090 ergo_format_ms("predicted pause time")
tonyp@3114 3091 ergo_format_ms("target pause time"),
tonyp@3114 3092 eden_region_num, survivor_region_num, old_region_num,
tonyp@3114 3093 predicted_pause_time_ms, target_pause_time_ms);
tonyp@3114 3094
ysr@777 3095 double non_young_end_time_sec = os::elapsedTime();
ysr@777 3096 _recorded_non_young_cset_choice_time_ms =
ysr@777 3097 (non_young_end_time_sec - non_young_start_time_sec) * 1000.0;
ysr@777 3098 }
ysr@777 3099
ysr@777 3100 void G1CollectorPolicy_BestRegionsFirst::record_full_collection_end() {
ysr@777 3101 G1CollectorPolicy::record_full_collection_end();
ysr@777 3102 _collectionSetChooser->updateAfterFullCollection();
ysr@777 3103 }
ysr@777 3104
ysr@777 3105 void G1CollectorPolicy_BestRegionsFirst::
tonyp@2062 3106 record_collection_pause_end() {
tonyp@2062 3107 G1CollectorPolicy::record_collection_pause_end();
ysr@777 3108 assert(assertMarkedBytesDataOK(), "Marked regions not OK at pause end.");
ysr@777 3109 }

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