Tue, 26 Jan 2010 16:52:29 -0800
6920090: G1: Disable ReduceInitialCardMarks at least until 6920109 is fixed
Summary: G1 now answers "no" to the query can_elide_initializing_store_barrier() in the product build. A debug flag allows alternate behaviour in debug builds.
Reviewed-by: iveresov, tonyp
ysr@777 | 1 | /* |
xdono@1279 | 2 | * Copyright 2001-2009 Sun Microsystems, Inc. All Rights Reserved. |
ysr@777 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
ysr@777 | 4 | * |
ysr@777 | 5 | * This code is free software; you can redistribute it and/or modify it |
ysr@777 | 6 | * under the terms of the GNU General Public License version 2 only, as |
ysr@777 | 7 | * published by the Free Software Foundation. |
ysr@777 | 8 | * |
ysr@777 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
ysr@777 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
ysr@777 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
ysr@777 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
ysr@777 | 13 | * accompanied this code). |
ysr@777 | 14 | * |
ysr@777 | 15 | * You should have received a copy of the GNU General Public License version |
ysr@777 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
ysr@777 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
ysr@777 | 18 | * |
ysr@777 | 19 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
ysr@777 | 20 | * CA 95054 USA or visit www.sun.com if you need additional information or |
ysr@777 | 21 | * have any questions. |
ysr@777 | 22 | * |
ysr@777 | 23 | */ |
ysr@777 | 24 | |
ysr@777 | 25 | #include "incls/_precompiled.incl" |
ysr@777 | 26 | #include "incls/_concurrentMarkThread.cpp.incl" |
ysr@777 | 27 | |
ysr@777 | 28 | // ======= Concurrent Mark Thread ======== |
ysr@777 | 29 | |
ysr@777 | 30 | // The CM thread is created when the G1 garbage collector is used |
ysr@777 | 31 | |
ysr@777 | 32 | SurrogateLockerThread* |
ysr@777 | 33 | ConcurrentMarkThread::_slt = NULL; |
ysr@777 | 34 | |
ysr@777 | 35 | ConcurrentMarkThread::ConcurrentMarkThread(ConcurrentMark* cm) : |
ysr@777 | 36 | ConcurrentGCThread(), |
ysr@777 | 37 | _cm(cm), |
ysr@777 | 38 | _started(false), |
ysr@777 | 39 | _in_progress(false), |
ysr@777 | 40 | _vtime_accum(0.0), |
ysr@777 | 41 | _vtime_mark_accum(0.0), |
ysr@777 | 42 | _vtime_count_accum(0.0) |
ysr@777 | 43 | { |
ysr@777 | 44 | create_and_start(); |
ysr@777 | 45 | } |
ysr@777 | 46 | |
ysr@777 | 47 | class CMCheckpointRootsInitialClosure: public VoidClosure { |
ysr@777 | 48 | |
ysr@777 | 49 | ConcurrentMark* _cm; |
ysr@777 | 50 | public: |
ysr@777 | 51 | |
ysr@777 | 52 | CMCheckpointRootsInitialClosure(ConcurrentMark* cm) : |
ysr@777 | 53 | _cm(cm) {} |
ysr@777 | 54 | |
ysr@777 | 55 | void do_void(){ |
ysr@777 | 56 | _cm->checkpointRootsInitial(); |
ysr@777 | 57 | } |
ysr@777 | 58 | }; |
ysr@777 | 59 | |
ysr@777 | 60 | class CMCheckpointRootsFinalClosure: public VoidClosure { |
ysr@777 | 61 | |
ysr@777 | 62 | ConcurrentMark* _cm; |
ysr@777 | 63 | public: |
ysr@777 | 64 | |
ysr@777 | 65 | CMCheckpointRootsFinalClosure(ConcurrentMark* cm) : |
ysr@777 | 66 | _cm(cm) {} |
ysr@777 | 67 | |
ysr@777 | 68 | void do_void(){ |
ysr@777 | 69 | _cm->checkpointRootsFinal(false); // !clear_all_soft_refs |
ysr@777 | 70 | } |
ysr@777 | 71 | }; |
ysr@777 | 72 | |
ysr@777 | 73 | class CMCleanUp: public VoidClosure { |
ysr@777 | 74 | ConcurrentMark* _cm; |
ysr@777 | 75 | public: |
ysr@777 | 76 | |
ysr@777 | 77 | CMCleanUp(ConcurrentMark* cm) : |
ysr@777 | 78 | _cm(cm) {} |
ysr@777 | 79 | |
ysr@777 | 80 | void do_void(){ |
ysr@777 | 81 | _cm->cleanup(); |
ysr@777 | 82 | } |
ysr@777 | 83 | }; |
ysr@777 | 84 | |
ysr@777 | 85 | |
ysr@777 | 86 | |
ysr@777 | 87 | void ConcurrentMarkThread::run() { |
ysr@777 | 88 | initialize_in_thread(); |
ysr@777 | 89 | _vtime_start = os::elapsedVTime(); |
ysr@777 | 90 | wait_for_universe_init(); |
ysr@777 | 91 | |
ysr@777 | 92 | G1CollectedHeap* g1 = G1CollectedHeap::heap(); |
ysr@777 | 93 | G1CollectorPolicy* g1_policy = g1->g1_policy(); |
ysr@777 | 94 | G1MMUTracker *mmu_tracker = g1_policy->mmu_tracker(); |
ysr@777 | 95 | Thread *current_thread = Thread::current(); |
ysr@777 | 96 | |
ysr@777 | 97 | while (!_should_terminate) { |
ysr@777 | 98 | // wait until started is set. |
ysr@777 | 99 | sleepBeforeNextCycle(); |
ysr@777 | 100 | { |
ysr@777 | 101 | ResourceMark rm; |
ysr@777 | 102 | HandleMark hm; |
ysr@777 | 103 | double cycle_start = os::elapsedVTime(); |
ysr@777 | 104 | double mark_start_sec = os::elapsedTime(); |
ysr@777 | 105 | char verbose_str[128]; |
ysr@777 | 106 | |
ysr@777 | 107 | if (PrintGC) { |
ysr@777 | 108 | gclog_or_tty->date_stamp(PrintGCDateStamps); |
ysr@777 | 109 | gclog_or_tty->stamp(PrintGCTimeStamps); |
tonyp@1054 | 110 | gclog_or_tty->print_cr("[GC concurrent-mark-start]"); |
ysr@777 | 111 | } |
ysr@777 | 112 | |
ysr@777 | 113 | if (!g1_policy->in_young_gc_mode()) { |
ysr@777 | 114 | // this ensures the flag is not set if we bail out of the marking |
ysr@777 | 115 | // cycle; normally the flag is cleared immediately after cleanup |
ysr@777 | 116 | g1->set_marking_complete(); |
ysr@777 | 117 | |
ysr@777 | 118 | if (g1_policy->adaptive_young_list_length()) { |
ysr@777 | 119 | double now = os::elapsedTime(); |
ysr@777 | 120 | double init_prediction_ms = g1_policy->predict_init_time_ms(); |
ysr@777 | 121 | jlong sleep_time_ms = mmu_tracker->when_ms(now, init_prediction_ms); |
ysr@777 | 122 | os::sleep(current_thread, sleep_time_ms, false); |
ysr@777 | 123 | } |
ysr@777 | 124 | |
ysr@777 | 125 | // We don't have to skip here if we've been asked to restart, because |
ysr@777 | 126 | // in the worst case we just enqueue a new VM operation to start a |
ysr@777 | 127 | // marking. Note that the init operation resets has_aborted() |
ysr@777 | 128 | CMCheckpointRootsInitialClosure init_cl(_cm); |
ysr@777 | 129 | strcpy(verbose_str, "GC initial-mark"); |
ysr@777 | 130 | VM_CGC_Operation op(&init_cl, verbose_str); |
ysr@777 | 131 | VMThread::execute(&op); |
ysr@777 | 132 | } |
ysr@777 | 133 | |
ysr@777 | 134 | int iter = 0; |
ysr@777 | 135 | do { |
ysr@777 | 136 | iter++; |
ysr@777 | 137 | if (!cm()->has_aborted()) { |
ysr@777 | 138 | _cm->markFromRoots(); |
ysr@777 | 139 | } |
ysr@777 | 140 | |
ysr@777 | 141 | double mark_end_time = os::elapsedVTime(); |
ysr@777 | 142 | double mark_end_sec = os::elapsedTime(); |
ysr@777 | 143 | _vtime_mark_accum += (mark_end_time - cycle_start); |
ysr@777 | 144 | if (!cm()->has_aborted()) { |
ysr@777 | 145 | if (g1_policy->adaptive_young_list_length()) { |
ysr@777 | 146 | double now = os::elapsedTime(); |
ysr@777 | 147 | double remark_prediction_ms = g1_policy->predict_remark_time_ms(); |
ysr@777 | 148 | jlong sleep_time_ms = mmu_tracker->when_ms(now, remark_prediction_ms); |
ysr@777 | 149 | os::sleep(current_thread, sleep_time_ms, false); |
ysr@777 | 150 | } |
ysr@777 | 151 | |
ysr@777 | 152 | if (PrintGC) { |
ysr@777 | 153 | gclog_or_tty->date_stamp(PrintGCDateStamps); |
ysr@777 | 154 | gclog_or_tty->stamp(PrintGCTimeStamps); |
ysr@777 | 155 | gclog_or_tty->print_cr("[GC concurrent-mark-end, %1.7lf sec]", |
ysr@777 | 156 | mark_end_sec - mark_start_sec); |
ysr@777 | 157 | } |
ysr@777 | 158 | |
ysr@777 | 159 | CMCheckpointRootsFinalClosure final_cl(_cm); |
ysr@777 | 160 | sprintf(verbose_str, "GC remark"); |
ysr@777 | 161 | VM_CGC_Operation op(&final_cl, verbose_str); |
ysr@777 | 162 | VMThread::execute(&op); |
ysr@777 | 163 | } |
ysr@777 | 164 | if (cm()->restart_for_overflow() && |
ysr@777 | 165 | G1TraceMarkStackOverflow) { |
ysr@777 | 166 | gclog_or_tty->print_cr("Restarting conc marking because of MS overflow " |
ysr@777 | 167 | "in remark (restart #%d).", iter); |
ysr@777 | 168 | } |
ysr@777 | 169 | |
ysr@777 | 170 | if (cm()->restart_for_overflow()) { |
ysr@777 | 171 | if (PrintGC) { |
ysr@777 | 172 | gclog_or_tty->date_stamp(PrintGCDateStamps); |
ysr@777 | 173 | gclog_or_tty->stamp(PrintGCTimeStamps); |
ysr@777 | 174 | gclog_or_tty->print_cr("[GC concurrent-mark-restart-for-overflow]"); |
ysr@777 | 175 | } |
ysr@777 | 176 | } |
ysr@777 | 177 | } while (cm()->restart_for_overflow()); |
ysr@777 | 178 | double counting_start_time = os::elapsedVTime(); |
ysr@777 | 179 | |
ysr@777 | 180 | // YSR: These look dubious (i.e. redundant) !!! FIX ME |
ysr@777 | 181 | slt()->manipulatePLL(SurrogateLockerThread::acquirePLL); |
ysr@777 | 182 | slt()->manipulatePLL(SurrogateLockerThread::releaseAndNotifyPLL); |
ysr@777 | 183 | |
ysr@777 | 184 | if (!cm()->has_aborted()) { |
ysr@777 | 185 | double count_start_sec = os::elapsedTime(); |
ysr@777 | 186 | if (PrintGC) { |
ysr@777 | 187 | gclog_or_tty->date_stamp(PrintGCDateStamps); |
ysr@777 | 188 | gclog_or_tty->stamp(PrintGCTimeStamps); |
ysr@777 | 189 | gclog_or_tty->print_cr("[GC concurrent-count-start]"); |
ysr@777 | 190 | } |
ysr@777 | 191 | |
ysr@777 | 192 | _sts.join(); |
ysr@777 | 193 | _cm->calcDesiredRegions(); |
ysr@777 | 194 | _sts.leave(); |
ysr@777 | 195 | |
ysr@777 | 196 | if (!cm()->has_aborted()) { |
ysr@777 | 197 | double count_end_sec = os::elapsedTime(); |
ysr@777 | 198 | if (PrintGC) { |
ysr@777 | 199 | gclog_or_tty->date_stamp(PrintGCDateStamps); |
ysr@777 | 200 | gclog_or_tty->stamp(PrintGCTimeStamps); |
ysr@777 | 201 | gclog_or_tty->print_cr("[GC concurrent-count-end, %1.7lf]", |
ysr@777 | 202 | count_end_sec - count_start_sec); |
ysr@777 | 203 | } |
ysr@777 | 204 | } |
ysr@777 | 205 | } |
ysr@777 | 206 | double end_time = os::elapsedVTime(); |
ysr@777 | 207 | _vtime_count_accum += (end_time - counting_start_time); |
ysr@777 | 208 | // Update the total virtual time before doing this, since it will try |
ysr@777 | 209 | // to measure it to get the vtime for this marking. We purposely |
ysr@777 | 210 | // neglect the presumably-short "completeCleanup" phase here. |
ysr@777 | 211 | _vtime_accum = (end_time - _vtime_start); |
ysr@777 | 212 | if (!cm()->has_aborted()) { |
ysr@777 | 213 | if (g1_policy->adaptive_young_list_length()) { |
ysr@777 | 214 | double now = os::elapsedTime(); |
ysr@777 | 215 | double cleanup_prediction_ms = g1_policy->predict_cleanup_time_ms(); |
ysr@777 | 216 | jlong sleep_time_ms = mmu_tracker->when_ms(now, cleanup_prediction_ms); |
ysr@777 | 217 | os::sleep(current_thread, sleep_time_ms, false); |
ysr@777 | 218 | } |
ysr@777 | 219 | |
ysr@777 | 220 | CMCleanUp cl_cl(_cm); |
ysr@777 | 221 | sprintf(verbose_str, "GC cleanup"); |
ysr@777 | 222 | VM_CGC_Operation op(&cl_cl, verbose_str); |
ysr@777 | 223 | VMThread::execute(&op); |
ysr@777 | 224 | } else { |
ysr@777 | 225 | G1CollectedHeap::heap()->set_marking_complete(); |
ysr@777 | 226 | } |
ysr@777 | 227 | |
ysr@777 | 228 | if (!cm()->has_aborted()) { |
ysr@777 | 229 | double cleanup_start_sec = os::elapsedTime(); |
ysr@777 | 230 | if (PrintGC) { |
ysr@777 | 231 | gclog_or_tty->date_stamp(PrintGCDateStamps); |
ysr@777 | 232 | gclog_or_tty->stamp(PrintGCTimeStamps); |
ysr@777 | 233 | gclog_or_tty->print_cr("[GC concurrent-cleanup-start]"); |
ysr@777 | 234 | } |
ysr@777 | 235 | |
ysr@777 | 236 | // Now do the remainder of the cleanup operation. |
ysr@777 | 237 | _sts.join(); |
ysr@777 | 238 | _cm->completeCleanup(); |
ysr@777 | 239 | if (!cm()->has_aborted()) { |
ysr@777 | 240 | g1_policy->record_concurrent_mark_cleanup_completed(); |
ysr@777 | 241 | |
ysr@777 | 242 | double cleanup_end_sec = os::elapsedTime(); |
ysr@777 | 243 | if (PrintGC) { |
ysr@777 | 244 | gclog_or_tty->date_stamp(PrintGCDateStamps); |
ysr@777 | 245 | gclog_or_tty->stamp(PrintGCTimeStamps); |
ysr@777 | 246 | gclog_or_tty->print_cr("[GC concurrent-cleanup-end, %1.7lf]", |
ysr@777 | 247 | cleanup_end_sec - cleanup_start_sec); |
ysr@777 | 248 | } |
ysr@777 | 249 | } |
ysr@777 | 250 | _sts.leave(); |
ysr@777 | 251 | } |
ysr@777 | 252 | // We're done: no more unclean regions coming. |
ysr@777 | 253 | G1CollectedHeap::heap()->set_unclean_regions_coming(false); |
ysr@777 | 254 | |
ysr@777 | 255 | if (cm()->has_aborted()) { |
ysr@777 | 256 | if (PrintGC) { |
ysr@777 | 257 | gclog_or_tty->date_stamp(PrintGCDateStamps); |
ysr@777 | 258 | gclog_or_tty->stamp(PrintGCTimeStamps); |
ysr@777 | 259 | gclog_or_tty->print_cr("[GC concurrent-mark-abort]"); |
ysr@777 | 260 | } |
ysr@777 | 261 | } |
ysr@777 | 262 | |
ysr@777 | 263 | // we now want to allow clearing of the marking bitmap to be |
ysr@777 | 264 | // suspended by a collection pause. |
ysr@777 | 265 | _sts.join(); |
ysr@777 | 266 | _cm->clearNextBitmap(); |
ysr@777 | 267 | _sts.leave(); |
ysr@777 | 268 | } |
ysr@777 | 269 | } |
ysr@777 | 270 | assert(_should_terminate, "just checking"); |
ysr@777 | 271 | |
ysr@777 | 272 | terminate(); |
ysr@777 | 273 | } |
ysr@777 | 274 | |
ysr@777 | 275 | |
ysr@777 | 276 | void ConcurrentMarkThread::yield() { |
ysr@777 | 277 | _sts.yield("Concurrent Mark"); |
ysr@777 | 278 | } |
ysr@777 | 279 | |
ysr@777 | 280 | void ConcurrentMarkThread::stop() { |
ysr@777 | 281 | // it is ok to take late safepoints here, if needed |
ysr@777 | 282 | MutexLockerEx mu(Terminator_lock); |
ysr@777 | 283 | _should_terminate = true; |
ysr@777 | 284 | while (!_has_terminated) { |
ysr@777 | 285 | Terminator_lock->wait(); |
ysr@777 | 286 | } |
ysr@777 | 287 | } |
ysr@777 | 288 | |
tonyp@1454 | 289 | void ConcurrentMarkThread::print() const { |
tonyp@1454 | 290 | print_on(tty); |
tonyp@1454 | 291 | } |
tonyp@1454 | 292 | |
tonyp@1454 | 293 | void ConcurrentMarkThread::print_on(outputStream* st) const { |
tonyp@1454 | 294 | st->print("\"G1 Main Concurrent Mark GC Thread\" "); |
tonyp@1454 | 295 | Thread::print_on(st); |
tonyp@1454 | 296 | st->cr(); |
ysr@777 | 297 | } |
ysr@777 | 298 | |
ysr@777 | 299 | void ConcurrentMarkThread::sleepBeforeNextCycle() { |
ysr@777 | 300 | clear_in_progress(); |
ysr@777 | 301 | // We join here because we don't want to do the "shouldConcurrentMark()" |
ysr@777 | 302 | // below while the world is otherwise stopped. |
ysr@777 | 303 | MutexLockerEx x(CGC_lock, Mutex::_no_safepoint_check_flag); |
ysr@777 | 304 | while (!started()) { |
ysr@777 | 305 | CGC_lock->wait(Mutex::_no_safepoint_check_flag); |
ysr@777 | 306 | } |
ysr@777 | 307 | set_in_progress(); |
ysr@777 | 308 | clear_started(); |
ysr@777 | 309 | } |
ysr@777 | 310 | |
ysr@777 | 311 | // Note: this method, although exported by the ConcurrentMarkSweepThread, |
ysr@777 | 312 | // which is a non-JavaThread, can only be called by a JavaThread. |
ysr@777 | 313 | // Currently this is done at vm creation time (post-vm-init) by the |
ysr@777 | 314 | // main/Primordial (Java)Thread. |
ysr@777 | 315 | // XXX Consider changing this in the future to allow the CMS thread |
ysr@777 | 316 | // itself to create this thread? |
ysr@777 | 317 | void ConcurrentMarkThread::makeSurrogateLockerThread(TRAPS) { |
ysr@777 | 318 | assert(_slt == NULL, "SLT already created"); |
ysr@777 | 319 | _slt = SurrogateLockerThread::make(THREAD); |
ysr@777 | 320 | } |