Mercurial > hg > truffle
annotate src/share/vm/gc_implementation/g1/concurrentG1RefineThread.cpp @ 1111:44f61c24ddab
6862387: tune concurrent refinement further
Summary: Reworked the concurrent refinement: threads activation, feedback-based threshold adjustment, other miscellaneous fixes.
Reviewed-by: apetrusenko, tonyp
| author | iveresov |
|---|---|
| date | Wed, 16 Dec 2009 15:12:51 -0800 |
| parents | 035d2e036a9b |
| children | b81f3572f355 |
| rev | line source |
|---|---|
| 342 | 1 /* |
| 844 | 2 * Copyright 2001-2009 Sun Microsystems, Inc. All Rights Reserved. |
| 342 | 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, | |
| 20 * CA 95054 USA or visit www.sun.com if you need additional information or | |
| 21 * have any questions. | |
| 22 * | |
| 23 */ | |
| 24 | |
| 25 #include "incls/_precompiled.incl" | |
| 26 #include "incls/_concurrentG1RefineThread.cpp.incl" | |
| 27 | |
| 28 ConcurrentG1RefineThread:: | |
|
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29 ConcurrentG1RefineThread(ConcurrentG1Refine* cg1r, ConcurrentG1RefineThread *next, |
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6841831: G1: assert(contains_reference(from),"We just added it!") fires
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30 int worker_id_offset, int worker_id) : |
| 342 | 31 ConcurrentGCThread(), |
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32 _worker_id_offset(worker_id_offset), |
| 794 | 33 _worker_id(worker_id), |
| 34 _active(false), | |
| 35 _next(next), | |
| 1111 | 36 _monitor(NULL), |
| 342 | 37 _cg1r(cg1r), |
| 1111 | 38 _vtime_accum(0.0) |
| 342 | 39 { |
| 1111 | 40 |
| 41 // Each thread has its own monitor. The i-th thread is responsible for signalling | |
| 42 // to thread i+1 if the number of buffers in the queue exceeds a threashold for this | |
| 43 // thread. Monitors are also used to wake up the threads during termination. | |
| 44 // The 0th worker in notified by mutator threads and has a special monitor. | |
| 45 // The last worker is used for young gen rset size sampling. | |
| 46 if (worker_id > 0) { | |
| 47 _monitor = new Monitor(Mutex::nonleaf, "Refinement monitor", true); | |
| 48 } else { | |
| 49 _monitor = DirtyCardQ_CBL_mon; | |
| 50 } | |
| 51 initialize(); | |
| 342 | 52 create_and_start(); |
| 53 } | |
| 54 | |
| 1111 | 55 void ConcurrentG1RefineThread::initialize() { |
| 56 if (_worker_id < cg1r()->worker_thread_num()) { | |
| 57 // Current thread activation threshold | |
| 58 _threshold = MIN2<int>(cg1r()->thread_threshold_step() * (_worker_id + 1) + cg1r()->green_zone(), | |
| 59 cg1r()->yellow_zone()); | |
| 60 // A thread deactivates once the number of buffer reached a deactivation threshold | |
| 61 _deactivation_threshold = MAX2<int>(_threshold - cg1r()->thread_threshold_step(), cg1r()->green_zone()); | |
| 62 } else { | |
| 63 set_active(true); | |
| 64 } | |
| 65 } | |
| 66 | |
| 342 | 67 void ConcurrentG1RefineThread::sample_young_list_rs_lengths() { |
| 68 G1CollectedHeap* g1h = G1CollectedHeap::heap(); | |
| 69 G1CollectorPolicy* g1p = g1h->g1_policy(); | |
| 70 if (g1p->adaptive_young_list_length()) { | |
| 71 int regions_visited = 0; | |
| 72 g1h->young_list_rs_length_sampling_init(); | |
| 73 while (g1h->young_list_rs_length_sampling_more()) { | |
| 74 g1h->young_list_rs_length_sampling_next(); | |
| 75 ++regions_visited; | |
| 76 | |
| 77 // we try to yield every time we visit 10 regions | |
| 78 if (regions_visited == 10) { | |
| 79 if (_sts.should_yield()) { | |
| 80 _sts.yield("G1 refine"); | |
| 81 // we just abandon the iteration | |
| 82 break; | |
| 83 } | |
| 84 regions_visited = 0; | |
| 85 } | |
| 86 } | |
| 87 | |
| 88 g1p->check_prediction_validity(); | |
| 89 } | |
| 90 } | |
| 91 | |
| 1111 | 92 void ConcurrentG1RefineThread::run_young_rs_sampling() { |
| 93 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); | |
| 342 | 94 _vtime_start = os::elapsedVTime(); |
| 1111 | 95 while(!_should_terminate) { |
| 96 _sts.join(); | |
| 97 sample_young_list_rs_lengths(); | |
| 98 _sts.leave(); | |
| 342 | 99 |
| 1111 | 100 if (os::supports_vtime()) { |
| 101 _vtime_accum = (os::elapsedVTime() - _vtime_start); | |
| 102 } else { | |
| 103 _vtime_accum = 0.0; | |
| 794 | 104 } |
| 105 | |
| 1111 | 106 MutexLockerEx x(_monitor, Mutex::_no_safepoint_check_flag); |
| 107 if (_should_terminate) { | |
| 108 break; | |
| 109 } | |
| 110 _monitor->wait(Mutex::_no_safepoint_check_flag, G1ConcRefineServiceInterval); | |
| 111 } | |
| 112 } | |
| 794 | 113 |
| 1111 | 114 void ConcurrentG1RefineThread::wait_for_completed_buffers() { |
| 115 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); | |
| 116 MutexLockerEx x(_monitor, Mutex::_no_safepoint_check_flag); | |
| 117 while (!_should_terminate && !is_active()) { | |
| 118 _monitor->wait(Mutex::_no_safepoint_check_flag); | |
| 119 } | |
| 120 } | |
| 121 | |
| 122 bool ConcurrentG1RefineThread::is_active() { | |
| 123 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); | |
| 124 return _worker_id > 0 ? _active : dcqs.process_completed_buffers(); | |
| 125 } | |
| 126 | |
| 127 void ConcurrentG1RefineThread::activate() { | |
| 128 MutexLockerEx x(_monitor, Mutex::_no_safepoint_check_flag); | |
| 129 if (_worker_id > 0) { | |
| 130 if (G1TraceConcurrentRefinement) { | |
| 131 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); | |
| 132 gclog_or_tty->print_cr("G1-Refine-activated worker %d, on threshold %d, current %d", | |
| 133 _worker_id, _threshold, (int)dcqs.completed_buffers_num()); | |
| 342 | 134 } |
| 1111 | 135 set_active(true); |
| 136 } else { | |
| 137 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); | |
| 138 dcqs.set_process_completed(true); | |
| 139 } | |
| 140 _monitor->notify(); | |
| 141 } | |
| 794 | 142 |
| 1111 | 143 void ConcurrentG1RefineThread::deactivate() { |
| 144 MutexLockerEx x(_monitor, Mutex::_no_safepoint_check_flag); | |
| 145 if (_worker_id > 0) { | |
| 146 if (G1TraceConcurrentRefinement) { | |
| 147 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); | |
| 148 gclog_or_tty->print_cr("G1-Refine-deactivated worker %d, off threshold %d, current %d", | |
| 149 _worker_id, _deactivation_threshold, (int)dcqs.completed_buffers_num()); | |
| 150 } | |
| 151 set_active(false); | |
| 152 } else { | |
| 153 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); | |
| 154 dcqs.set_process_completed(false); | |
| 155 } | |
| 156 } | |
| 157 | |
| 158 void ConcurrentG1RefineThread::run() { | |
| 159 initialize_in_thread(); | |
| 160 wait_for_universe_init(); | |
| 794 | 161 |
| 1111 | 162 if (_worker_id >= cg1r()->worker_thread_num()) { |
| 163 run_young_rs_sampling(); | |
| 164 terminate(); | |
| 165 } | |
| 166 | |
| 167 _vtime_start = os::elapsedVTime(); | |
| 168 while (!_should_terminate) { | |
| 169 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); | |
| 170 | |
| 171 // Wait for work | |
| 172 wait_for_completed_buffers(); | |
| 173 | |
| 174 if (_should_terminate) { | |
| 175 break; | |
| 176 } | |
| 177 | |
| 178 _sts.join(); | |
| 179 | |
| 180 do { | |
| 181 int curr_buffer_num = (int)dcqs.completed_buffers_num(); | |
| 182 // If the number of the buffers falls down into the yellow zone, | |
| 183 // that means that the transition period after the evacuation pause has ended. | |
| 184 if (dcqs.completed_queue_padding() > 0 && curr_buffer_num <= cg1r()->yellow_zone()) { | |
| 185 dcqs.set_completed_queue_padding(0); | |
| 794 | 186 } |
| 1111 | 187 |
| 188 if (_worker_id > 0 && curr_buffer_num <= _deactivation_threshold) { | |
| 794 | 189 // If the number of the buffer has fallen below our threshold |
| 190 // we should deactivate. The predecessor will reactivate this | |
| 191 // thread should the number of the buffers cross the threshold again. | |
| 192 deactivate(); | |
| 193 break; | |
| 194 } | |
| 195 | |
| 196 // Check if we need to activate the next thread. | |
| 1111 | 197 if (_next != NULL && !_next->is_active() && curr_buffer_num > _next->_threshold) { |
| 794 | 198 _next->activate(); |
| 199 } | |
| 1111 | 200 } while (dcqs.apply_closure_to_completed_buffer(_worker_id + _worker_id_offset, cg1r()->green_zone())); |
| 794 | 201 |
| 1111 | 202 // We can exit the loop above while being active if there was a yield request. |
| 203 if (is_active()) { | |
| 204 deactivate(); | |
| 794 | 205 } |
| 1111 | 206 |
| 342 | 207 _sts.leave(); |
| 794 | 208 |
| 342 | 209 if (os::supports_vtime()) { |
| 210 _vtime_accum = (os::elapsedVTime() - _vtime_start); | |
| 211 } else { | |
| 212 _vtime_accum = 0.0; | |
| 213 } | |
| 214 } | |
| 215 assert(_should_terminate, "just checking"); | |
| 216 terminate(); | |
| 217 } | |
| 218 | |
| 219 | |
| 220 void ConcurrentG1RefineThread::yield() { | |
| 751 | 221 if (G1TraceConcurrentRefinement) gclog_or_tty->print_cr("G1-Refine-yield"); |
| 342 | 222 _sts.yield("G1 refine"); |
| 751 | 223 if (G1TraceConcurrentRefinement) gclog_or_tty->print_cr("G1-Refine-yield-end"); |
| 342 | 224 } |
| 225 | |
| 226 void ConcurrentG1RefineThread::stop() { | |
| 227 // it is ok to take late safepoints here, if needed | |
| 228 { | |
| 229 MutexLockerEx mu(Terminator_lock); | |
| 230 _should_terminate = true; | |
| 231 } | |
| 232 | |
| 233 { | |
| 1111 | 234 MutexLockerEx x(_monitor, Mutex::_no_safepoint_check_flag); |
| 235 _monitor->notify(); | |
| 342 | 236 } |
| 237 | |
| 238 { | |
| 239 MutexLockerEx mu(Terminator_lock); | |
| 240 while (!_has_terminated) { | |
| 241 Terminator_lock->wait(); | |
| 242 } | |
| 243 } | |
| 751 | 244 if (G1TraceConcurrentRefinement) gclog_or_tty->print_cr("G1-Refine-stop"); |
| 342 | 245 } |
| 246 | |
| 1019 | 247 void ConcurrentG1RefineThread::print() const { |
| 248 print_on(tty); | |
| 342 | 249 } |
| 1019 | 250 |
| 251 void ConcurrentG1RefineThread::print_on(outputStream* st) const { | |
| 252 st->print("\"G1 Concurrent Refinement Thread#%d\" ", _worker_id); | |
| 253 Thread::print_on(st); | |
| 254 st->cr(); | |
| 255 } |