1 /*
   2  * Copyright (c) 2013, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "gc/g1/g1CollectedHeap.inline.hpp"
  27 #include "gc/g1/g1GCPhaseTimes.hpp"
  28 #include "gc/g1/g1HotCardCache.hpp"
  29 #include "gc/g1/g1StringDedup.hpp"
  30 #include "gc/g1/workerDataArray.inline.hpp"
  31 #include "memory/resourceArea.hpp"
  32 #include "logging/log.hpp"
  33 #include "runtime/timer.hpp"
  34 #include "runtime/os.hpp"
  35 
  36 static const char* Indents[5] = {"", "  ", "    ", "      ", "        "};
  37 
  38 G1GCPhaseTimes::G1GCPhaseTimes(uint max_gc_threads) :
  39   _max_gc_threads(max_gc_threads),
  40   _gc_start_counter(0),
  41   _gc_pause_time_ms(0.0)
  42 {
  43   assert(max_gc_threads > 0, "Must have some GC threads");
  44 
  45   _gc_par_phases[GCWorkerStart] = new WorkerDataArray<double>(max_gc_threads, "GC Worker Start (ms):");
  46   _gc_par_phases[ExtRootScan] = new WorkerDataArray<double>(max_gc_threads, "Ext Root Scanning (ms):");
  47 
  48   // Root scanning phases
  49   _gc_par_phases[ThreadRoots] = new WorkerDataArray<double>(max_gc_threads, "Thread Roots (ms):");
  50   _gc_par_phases[StringTableRoots] = new WorkerDataArray<double>(max_gc_threads, "StringTable Roots (ms):");
  51   _gc_par_phases[UniverseRoots] = new WorkerDataArray<double>(max_gc_threads, "Universe Roots (ms):");
  52   _gc_par_phases[JNIRoots] = new WorkerDataArray<double>(max_gc_threads, "JNI Handles Roots (ms):");
  53   _gc_par_phases[ObjectSynchronizerRoots] = new WorkerDataArray<double>(max_gc_threads, "ObjectSynchronizer Roots (ms):");
  54   _gc_par_phases[ManagementRoots] = new WorkerDataArray<double>(max_gc_threads, "Management Roots (ms):");
  55   _gc_par_phases[SystemDictionaryRoots] = new WorkerDataArray<double>(max_gc_threads, "SystemDictionary Roots (ms):");
  56   _gc_par_phases[CLDGRoots] = new WorkerDataArray<double>(max_gc_threads, "CLDG Roots (ms):");
  57   _gc_par_phases[JVMTIRoots] = new WorkerDataArray<double>(max_gc_threads, "JVMTI Roots (ms):");
  58   _gc_par_phases[CMRefRoots] = new WorkerDataArray<double>(max_gc_threads, "CM RefProcessor Roots (ms):");
  59   _gc_par_phases[WaitForStrongCLD] = new WorkerDataArray<double>(max_gc_threads, "Wait For Strong CLD (ms):");
  60   _gc_par_phases[WeakCLDRoots] = new WorkerDataArray<double>(max_gc_threads, "Weak CLD Roots (ms):");
  61   _gc_par_phases[SATBFiltering] = new WorkerDataArray<double>(max_gc_threads, "SATB Filtering (ms):");
  62 
  63   _gc_par_phases[UpdateRS] = new WorkerDataArray<double>(max_gc_threads, "Update RS (ms):");
  64   if (G1HotCardCache::default_use_cache()) {
  65     _gc_par_phases[ScanHCC] = new WorkerDataArray<double>(max_gc_threads, "Scan HCC (ms):");
  66   } else {
  67     _gc_par_phases[ScanHCC] = NULL;
  68   }
  69   _gc_par_phases[ScanRS] = new WorkerDataArray<double>(max_gc_threads, "Scan RS (ms):");
  70   _gc_par_phases[CodeRoots] = new WorkerDataArray<double>(max_gc_threads, "Code Root Scanning (ms):");
  71 #if INCLUDE_AOT
  72   _gc_par_phases[AOTCodeRoots] = new WorkerDataArray<double>(max_gc_threads, "AOT Root Scanning (ms):");
  73 #endif
  74   _gc_par_phases[ObjCopy] = new WorkerDataArray<double>(max_gc_threads, "Object Copy (ms):");
  75   _gc_par_phases[Termination] = new WorkerDataArray<double>(max_gc_threads, "Termination (ms):");
  76   _gc_par_phases[GCWorkerTotal] = new WorkerDataArray<double>(max_gc_threads, "GC Worker Total (ms):");
  77   _gc_par_phases[GCWorkerEnd] = new WorkerDataArray<double>(max_gc_threads, "GC Worker End (ms):");
  78   _gc_par_phases[Other] = new WorkerDataArray<double>(max_gc_threads, "GC Worker Other (ms):");
  79 
  80   _scan_rs_scanned_cards = new WorkerDataArray<size_t>(max_gc_threads, "Scanned Cards:");
  81   _gc_par_phases[ScanRS]->link_thread_work_items(_scan_rs_scanned_cards, ScannedCards);
  82   _scan_rs_claimed_cards = new WorkerDataArray<size_t>(max_gc_threads, "Claimed Cards:");
  83   _gc_par_phases[ScanRS]->link_thread_work_items(_scan_rs_claimed_cards, ClaimedCards);
  84   _scan_rs_skipped_cards = new WorkerDataArray<size_t>(max_gc_threads, "Skipped Cards:");
  85   _gc_par_phases[ScanRS]->link_thread_work_items(_scan_rs_skipped_cards, SkippedCards);
  86 
  87   _update_rs_processed_buffers = new WorkerDataArray<size_t>(max_gc_threads, "Processed Buffers:");
  88   _gc_par_phases[UpdateRS]->link_thread_work_items(_update_rs_processed_buffers);
  89 
  90   _termination_attempts = new WorkerDataArray<size_t>(max_gc_threads, "Termination Attempts:");
  91   _gc_par_phases[Termination]->link_thread_work_items(_termination_attempts);
  92 
  93   if (UseStringDeduplication) {
  94     _gc_par_phases[StringDedupQueueFixup] = new WorkerDataArray<double>(max_gc_threads, "Queue Fixup (ms):");
  95     _gc_par_phases[StringDedupTableFixup] = new WorkerDataArray<double>(max_gc_threads, "Table Fixup (ms):");
  96   } else {
  97     _gc_par_phases[StringDedupQueueFixup] = NULL;
  98     _gc_par_phases[StringDedupTableFixup] = NULL;
  99   }
 100 
 101   _gc_par_phases[RedirtyCards] = new WorkerDataArray<double>(max_gc_threads, "Parallel Redirty (ms):");
 102   _redirtied_cards = new WorkerDataArray<size_t>(max_gc_threads, "Redirtied Cards:");
 103   _gc_par_phases[RedirtyCards]->link_thread_work_items(_redirtied_cards);
 104 
 105   _gc_par_phases[YoungFreeCSet] = new WorkerDataArray<double>(max_gc_threads, "Young Free Collection Set (ms):");
 106   _gc_par_phases[NonYoungFreeCSet] = new WorkerDataArray<double>(max_gc_threads, "Non-Young Free Collection Set (ms):");
 107 
 108   _gc_par_phases[PreserveCMReferents] = new WorkerDataArray<double>(max_gc_threads, "Parallel Preserve CM Refs (ms):");
 109 
 110   reset();
 111 }
 112 
 113 void G1GCPhaseTimes::reset() {
 114   _cur_collection_par_time_ms = 0.0;
 115   _cur_collection_code_root_fixup_time_ms = 0.0;
 116   _cur_strong_code_root_purge_time_ms = 0.0;
 117   _cur_evac_fail_recalc_used = 0.0;
 118   _cur_evac_fail_restore_remsets = 0.0;
 119   _cur_evac_fail_remove_self_forwards = 0.0;
 120   _cur_string_dedup_fixup_time_ms = 0.0;
 121   _cur_prepare_tlab_time_ms = 0.0;
 122   _cur_resize_tlab_time_ms = 0.0;
 123   _cur_derived_pointer_table_update_time_ms = 0.0;
 124   _cur_clear_ct_time_ms = 0.0;
 125   _cur_expand_heap_time_ms = 0.0;
 126   _cur_ref_proc_time_ms = 0.0;
 127   _cur_ref_enq_time_ms = 0.0;
 128   _cur_collection_start_sec = 0.0;
 129   _root_region_scan_wait_time_ms = 0.0;
 130   _external_accounted_time_ms = 0.0;
 131   _recorded_clear_claimed_marks_time_ms = 0.0;
 132   _recorded_young_cset_choice_time_ms = 0.0;
 133   _recorded_non_young_cset_choice_time_ms = 0.0;
 134   _recorded_redirty_logged_cards_time_ms = 0.0;
 135   _recorded_preserve_cm_referents_time_ms = 0.0;
 136   _recorded_merge_pss_time_ms = 0.0;
 137   _recorded_start_new_cset_time_ms = 0.0;
 138   _recorded_total_free_cset_time_ms = 0.0;
 139   _recorded_serial_free_cset_time_ms = 0.0;
 140   _cur_fast_reclaim_humongous_time_ms = 0.0;
 141   _cur_fast_reclaim_humongous_register_time_ms = 0.0;
 142   _cur_fast_reclaim_humongous_total = 0;
 143   _cur_fast_reclaim_humongous_candidates = 0;
 144   _cur_fast_reclaim_humongous_reclaimed = 0;
 145   _cur_verify_before_time_ms = 0.0;
 146   _cur_verify_after_time_ms = 0.0;
 147 
 148   for (int i = 0; i < GCParPhasesSentinel; i++) {
 149     if (_gc_par_phases[i] != NULL) {
 150       _gc_par_phases[i]->reset();
 151     }
 152   }
 153 }
 154 
 155 void G1GCPhaseTimes::note_gc_start() {
 156   _gc_start_counter = os::elapsed_counter();
 157   reset();
 158 }
 159 
 160 #define ASSERT_PHASE_UNINITIALIZED(phase) \
 161     assert(_gc_par_phases[phase]->get(i) == uninitialized, "Phase " #phase " reported for thread that was not started");
 162 
 163 double G1GCPhaseTimes::worker_time(GCParPhases phase, uint worker) {
 164   double value = _gc_par_phases[phase]->get(worker);
 165   if (value != WorkerDataArray<double>::uninitialized()) {
 166     return value;
 167   }
 168   return 0.0;
 169 }
 170 
 171 void G1GCPhaseTimes::note_gc_end() {
 172   _gc_pause_time_ms = TimeHelper::counter_to_millis(os::elapsed_counter() - _gc_start_counter);
 173 
 174   double uninitialized = WorkerDataArray<double>::uninitialized();
 175 
 176   for (uint i = 0; i < _max_gc_threads; i++) {
 177     double worker_start = _gc_par_phases[GCWorkerStart]->get(i);
 178     if (worker_start != uninitialized) {
 179       assert(_gc_par_phases[GCWorkerEnd]->get(i) != uninitialized, "Worker started but not ended.");
 180       double total_worker_time = _gc_par_phases[GCWorkerEnd]->get(i) - _gc_par_phases[GCWorkerStart]->get(i);
 181       record_time_secs(GCWorkerTotal, i , total_worker_time);
 182 
 183       double worker_known_time =
 184           worker_time(ExtRootScan, i)
 185           + worker_time(SATBFiltering, i)
 186           + worker_time(UpdateRS, i)
 187           + worker_time(ScanRS, i)
 188           + worker_time(CodeRoots, i)
 189           + worker_time(ObjCopy, i)
 190           + worker_time(Termination, i);
 191 
 192       record_time_secs(Other, i, total_worker_time - worker_known_time);
 193     } else {
 194       // Make sure all slots are uninitialized since this thread did not seem to have been started
 195       ASSERT_PHASE_UNINITIALIZED(GCWorkerEnd);
 196       ASSERT_PHASE_UNINITIALIZED(ExtRootScan);
 197       ASSERT_PHASE_UNINITIALIZED(SATBFiltering);
 198       ASSERT_PHASE_UNINITIALIZED(UpdateRS);
 199       ASSERT_PHASE_UNINITIALIZED(ScanRS);
 200       ASSERT_PHASE_UNINITIALIZED(CodeRoots);
 201       ASSERT_PHASE_UNINITIALIZED(ObjCopy);
 202       ASSERT_PHASE_UNINITIALIZED(Termination);
 203     }
 204   }
 205 }
 206 
 207 #undef ASSERT_PHASE_UNINITIALIZED
 208 
 209 // record the time a phase took in seconds
 210 void G1GCPhaseTimes::record_time_secs(GCParPhases phase, uint worker_i, double secs) {
 211   _gc_par_phases[phase]->set(worker_i, secs);
 212 }
 213 
 214 // add a number of seconds to a phase
 215 void G1GCPhaseTimes::add_time_secs(GCParPhases phase, uint worker_i, double secs) {
 216   _gc_par_phases[phase]->add(worker_i, secs);
 217 }
 218 
 219 void G1GCPhaseTimes::record_thread_work_item(GCParPhases phase, uint worker_i, size_t count, uint index) {
 220   _gc_par_phases[phase]->set_thread_work_item(worker_i, count, index);
 221 }
 222 
 223 // return the average time for a phase in milliseconds
 224 double G1GCPhaseTimes::average_time_ms(GCParPhases phase) {
 225   return _gc_par_phases[phase]->average() * 1000.0;
 226 }
 227 
 228 size_t G1GCPhaseTimes::sum_thread_work_items(GCParPhases phase, uint index) {
 229   assert(_gc_par_phases[phase]->thread_work_items(index) != NULL, "No sub count");
 230   return _gc_par_phases[phase]->thread_work_items(index)->sum();
 231 }
 232 
 233 template <class T>
 234 void G1GCPhaseTimes::details(T* phase, const char* indent) const {
 235   Log(gc, phases, task) log;
 236   if (log.is_level(LogLevel::Trace)) {
 237     outputStream* trace_out = log.trace_stream();
 238     trace_out->print("%s", indent);
 239     phase->print_details_on(trace_out);
 240   }
 241 }
 242 
 243 void G1GCPhaseTimes::log_phase(WorkerDataArray<double>* phase, uint indent, outputStream* out, bool print_sum) const {
 244   out->print("%s", Indents[indent]);
 245   phase->print_summary_on(out, print_sum);
 246   details(phase, Indents[indent]);
 247 
 248   for (uint i = 0; i < phase->MaxThreadWorkItems; i++) {
 249     WorkerDataArray<size_t>* work_items = phase->thread_work_items(i);
 250     if (work_items != NULL) {
 251       out->print("%s", Indents[indent + 1]);
 252       work_items->print_summary_on(out, true);
 253       details(work_items, Indents[indent + 1]);
 254     }
 255   }
 256 }
 257 
 258 void G1GCPhaseTimes::debug_phase(WorkerDataArray<double>* phase) const {
 259   Log(gc, phases) log;
 260   if (log.is_level(LogLevel::Debug)) {
 261     ResourceMark rm;
 262     log_phase(phase, 2, log.debug_stream(), true);
 263   }
 264 }
 265 
 266 void G1GCPhaseTimes::trace_phase(WorkerDataArray<double>* phase, bool print_sum) const {
 267   Log(gc, phases) log;
 268   if (log.is_level(LogLevel::Trace)) {
 269     ResourceMark rm;
 270     log_phase(phase, 3, log.trace_stream(), print_sum);
 271   }
 272 }
 273 
 274 #define TIME_FORMAT "%.1lfms"
 275 
 276 void G1GCPhaseTimes::info_time(const char* name, double value) const {
 277   log_info(gc, phases)("%s%s: " TIME_FORMAT, Indents[1], name, value);
 278 }
 279 
 280 void G1GCPhaseTimes::debug_time(const char* name, double value) const {
 281   log_debug(gc, phases)("%s%s: " TIME_FORMAT, Indents[2], name, value);
 282 }
 283 
 284 void G1GCPhaseTimes::trace_time(const char* name, double value) const {
 285   log_trace(gc, phases)("%s%s: " TIME_FORMAT, Indents[3], name, value);
 286 }
 287 
 288 void G1GCPhaseTimes::trace_count(const char* name, size_t value) const {
 289   log_trace(gc, phases)("%s%s: " SIZE_FORMAT, Indents[3], name, value);
 290 }
 291 
 292 double G1GCPhaseTimes::print_pre_evacuate_collection_set() const {
 293   const double sum_ms = _root_region_scan_wait_time_ms +
 294                         _recorded_young_cset_choice_time_ms +
 295                         _recorded_non_young_cset_choice_time_ms +
 296                         _cur_fast_reclaim_humongous_register_time_ms +
 297                         _recorded_clear_claimed_marks_time_ms;
 298 
 299   info_time("Pre Evacuate Collection Set", sum_ms);
 300 
 301   if (_root_region_scan_wait_time_ms > 0.0) {
 302     debug_time("Root Region Scan Waiting", _root_region_scan_wait_time_ms);
 303   }
 304   debug_time("Prepare TLABs", _cur_prepare_tlab_time_ms);
 305   debug_time("Choose Collection Set", (_recorded_young_cset_choice_time_ms + _recorded_non_young_cset_choice_time_ms));
 306   if (G1EagerReclaimHumongousObjects) {
 307     debug_time("Humongous Register", _cur_fast_reclaim_humongous_register_time_ms);
 308     trace_count("Humongous Total", _cur_fast_reclaim_humongous_total);
 309     trace_count("Humongous Candidate", _cur_fast_reclaim_humongous_candidates);
 310   }
 311 
 312   if (_recorded_clear_claimed_marks_time_ms > 0.0) {
 313     debug_time("Clear Claimed Marks", _recorded_clear_claimed_marks_time_ms);
 314   }
 315   return sum_ms;
 316 }
 317 
 318 double G1GCPhaseTimes::print_evacuate_collection_set() const {
 319   const double sum_ms = _cur_collection_par_time_ms;
 320 
 321   info_time("Evacuate Collection Set", sum_ms);
 322 
 323   trace_phase(_gc_par_phases[GCWorkerStart], false);
 324   debug_phase(_gc_par_phases[ExtRootScan]);
 325   for (int i = ThreadRoots; i <= SATBFiltering; i++) {
 326     trace_phase(_gc_par_phases[i]);
 327   }
 328   debug_phase(_gc_par_phases[UpdateRS]);
 329   if (G1HotCardCache::default_use_cache()) {
 330     trace_phase(_gc_par_phases[ScanHCC]);
 331   }
 332   debug_phase(_gc_par_phases[ScanRS]);
 333   debug_phase(_gc_par_phases[CodeRoots]);
 334 #if INCLUDE_AOT
 335   debug_phase(_gc_par_phases[AOTCodeRoots]);
 336 #endif
 337   debug_phase(_gc_par_phases[ObjCopy]);
 338   debug_phase(_gc_par_phases[Termination]);
 339   debug_phase(_gc_par_phases[Other]);
 340   debug_phase(_gc_par_phases[GCWorkerTotal]);
 341   trace_phase(_gc_par_phases[GCWorkerEnd], false);
 342 
 343   return sum_ms;
 344 }
 345 
 346 double G1GCPhaseTimes::print_post_evacuate_collection_set() const {
 347   const double evac_fail_handling = _cur_evac_fail_recalc_used +
 348                                     _cur_evac_fail_remove_self_forwards +
 349                                     _cur_evac_fail_restore_remsets;
 350   const double sum_ms = evac_fail_handling +
 351                         _cur_collection_code_root_fixup_time_ms +
 352                         _recorded_preserve_cm_referents_time_ms +
 353                         _cur_ref_proc_time_ms +
 354                         _cur_ref_enq_time_ms +
 355                         _cur_clear_ct_time_ms +
 356                         _recorded_merge_pss_time_ms +
 357                         _cur_strong_code_root_purge_time_ms +
 358                         _recorded_redirty_logged_cards_time_ms +
 359                         _recorded_total_free_cset_time_ms +
 360                         _cur_fast_reclaim_humongous_time_ms +
 361                         _cur_expand_heap_time_ms +
 362                         _cur_string_dedup_fixup_time_ms;
 363 
 364   info_time("Post Evacuate Collection Set", sum_ms);
 365 
 366   debug_time("Code Roots Fixup", _cur_collection_code_root_fixup_time_ms);
 367 
 368   debug_time("Preserve CM Refs", _recorded_preserve_cm_referents_time_ms);
 369   trace_phase(_gc_par_phases[PreserveCMReferents]);
 370 
 371   debug_time("Reference Processing", _cur_ref_proc_time_ms);
 372 
 373   if (G1StringDedup::is_enabled()) {
 374     debug_time("String Dedup Fixup", _cur_string_dedup_fixup_time_ms);
 375     debug_phase(_gc_par_phases[StringDedupQueueFixup]);
 376     debug_phase(_gc_par_phases[StringDedupTableFixup]);
 377   }
 378 
 379   debug_time("Clear Card Table", _cur_clear_ct_time_ms);
 380 
 381   if (G1CollectedHeap::heap()->evacuation_failed()) {
 382     debug_time("Evacuation Failure", evac_fail_handling);
 383     trace_time("Recalculate Used", _cur_evac_fail_recalc_used);
 384     trace_time("Remove Self Forwards",_cur_evac_fail_remove_self_forwards);
 385     trace_time("Restore RemSet", _cur_evac_fail_restore_remsets);
 386   }
 387 
 388   debug_time("Reference Enqueuing", _cur_ref_enq_time_ms);
 389 
 390   debug_time("Merge Per-Thread State", _recorded_merge_pss_time_ms);
 391   debug_time("Code Roots Purge", _cur_strong_code_root_purge_time_ms);
 392 
 393   debug_time("Redirty Cards", _recorded_redirty_logged_cards_time_ms);
 394   trace_phase(_gc_par_phases[RedirtyCards]);
 395 #if defined(COMPILER2) || INCLUDE_JVMCI
 396   debug_time("DerivedPointerTable Update", _cur_derived_pointer_table_update_time_ms);
 397 #endif
 398 
 399   debug_time("Free Collection Set", _recorded_total_free_cset_time_ms);
 400   trace_time("Free Collection Set Serial", _recorded_serial_free_cset_time_ms);
 401   trace_phase(_gc_par_phases[YoungFreeCSet]);
 402   trace_phase(_gc_par_phases[NonYoungFreeCSet]);
 403 
 404   if (G1EagerReclaimHumongousObjects) {
 405     debug_time("Humongous Reclaim", _cur_fast_reclaim_humongous_time_ms);
 406     trace_count("Humongous Reclaimed", _cur_fast_reclaim_humongous_reclaimed);
 407   }
 408   debug_time("Start New Collection Set", _recorded_start_new_cset_time_ms);
 409   if (UseTLAB && ResizeTLAB) {
 410     debug_time("Resize TLABs", _cur_resize_tlab_time_ms);
 411   }
 412   debug_time("Expand Heap After Collection", _cur_expand_heap_time_ms);
 413 
 414 
 415   return sum_ms;
 416 }
 417 
 418 void G1GCPhaseTimes::print_other(double accounted_ms) const {
 419   info_time("Other", _gc_pause_time_ms - accounted_ms);
 420 }
 421 
 422 void G1GCPhaseTimes::print() {
 423   note_gc_end();
 424 
 425   if (_cur_verify_before_time_ms > 0.0) {
 426     debug_time("Verify Before", _cur_verify_before_time_ms);
 427   }
 428 
 429   double accounted_ms = 0.0;
 430   accounted_ms += print_pre_evacuate_collection_set();
 431   accounted_ms += print_evacuate_collection_set();
 432   accounted_ms += print_post_evacuate_collection_set();
 433   print_other(accounted_ms);
 434 
 435   if (_cur_verify_after_time_ms > 0.0) {
 436     debug_time("Verify After", _cur_verify_after_time_ms);
 437   }
 438 }
 439 
 440 G1GCParPhaseTimesTracker::G1GCParPhaseTimesTracker(G1GCPhaseTimes* phase_times, G1GCPhaseTimes::GCParPhases phase, uint worker_id) :
 441     _phase_times(phase_times), _phase(phase), _worker_id(worker_id) {
 442   if (_phase_times != NULL) {
 443     _start_time = os::elapsedTime();
 444   }
 445 }
 446 
 447 G1GCParPhaseTimesTracker::~G1GCParPhaseTimesTracker() {
 448   if (_phase_times != NULL) {
 449     _phase_times->record_time_secs(_phase, _worker_id, os::elapsedTime() - _start_time);
 450   }
 451 }
 452