Fri, 24 Jun 2016 17:12:13 +0800
[Code Reorganization] Removed GC related modifications made by Loongson, for example, UseOldNUMA.
aoqi@0 | 1 | /* |
aoqi@0 | 2 | * Copyright (c) 2002, 2014, Oracle and/or its affiliates. All rights reserved. |
aoqi@0 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
aoqi@0 | 4 | * |
aoqi@0 | 5 | * This code is free software; you can redistribute it and/or modify it |
aoqi@0 | 6 | * under the terms of the GNU General Public License version 2 only, as |
aoqi@0 | 7 | * published by the Free Software Foundation. |
aoqi@0 | 8 | * |
aoqi@0 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
aoqi@0 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
aoqi@0 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
aoqi@0 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
aoqi@0 | 13 | * accompanied this code). |
aoqi@0 | 14 | * |
aoqi@0 | 15 | * You should have received a copy of the GNU General Public License version |
aoqi@0 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
aoqi@0 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
aoqi@0 | 18 | * |
aoqi@0 | 19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
aoqi@0 | 20 | * or visit www.oracle.com if you need additional information or have any |
aoqi@0 | 21 | * questions. |
aoqi@0 | 22 | * |
aoqi@0 | 23 | */ |
aoqi@0 | 24 | |
aoqi@0 | 25 | #include "precompiled.hpp" |
aoqi@0 | 26 | #include "classfile/symbolTable.hpp" |
aoqi@0 | 27 | #include "code/codeCache.hpp" |
aoqi@0 | 28 | #include "gc_implementation/parallelScavenge/cardTableExtension.hpp" |
aoqi@0 | 29 | #include "gc_implementation/parallelScavenge/gcTaskManager.hpp" |
aoqi@0 | 30 | #include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp" |
aoqi@0 | 31 | #include "gc_implementation/parallelScavenge/psAdaptiveSizePolicy.hpp" |
aoqi@0 | 32 | #include "gc_implementation/parallelScavenge/psMarkSweep.hpp" |
aoqi@0 | 33 | #include "gc_implementation/parallelScavenge/psParallelCompact.hpp" |
aoqi@0 | 34 | #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp" |
aoqi@0 | 35 | #include "gc_implementation/parallelScavenge/psTasks.hpp" |
aoqi@0 | 36 | #include "gc_implementation/shared/gcHeapSummary.hpp" |
aoqi@0 | 37 | #include "gc_implementation/shared/gcTimer.hpp" |
aoqi@0 | 38 | #include "gc_implementation/shared/gcTrace.hpp" |
aoqi@0 | 39 | #include "gc_implementation/shared/gcTraceTime.hpp" |
aoqi@0 | 40 | #include "gc_implementation/shared/isGCActiveMark.hpp" |
aoqi@0 | 41 | #include "gc_implementation/shared/spaceDecorator.hpp" |
aoqi@0 | 42 | #include "gc_interface/gcCause.hpp" |
aoqi@0 | 43 | #include "memory/collectorPolicy.hpp" |
aoqi@0 | 44 | #include "memory/gcLocker.inline.hpp" |
aoqi@0 | 45 | #include "memory/referencePolicy.hpp" |
aoqi@0 | 46 | #include "memory/referenceProcessor.hpp" |
aoqi@0 | 47 | #include "memory/resourceArea.hpp" |
aoqi@0 | 48 | #include "oops/oop.inline.hpp" |
aoqi@0 | 49 | #include "oops/oop.psgc.inline.hpp" |
aoqi@0 | 50 | #include "runtime/biasedLocking.hpp" |
aoqi@0 | 51 | #include "runtime/fprofiler.hpp" |
aoqi@0 | 52 | #include "runtime/handles.inline.hpp" |
aoqi@0 | 53 | #include "runtime/threadCritical.hpp" |
aoqi@0 | 54 | #include "runtime/vmThread.hpp" |
aoqi@0 | 55 | #include "runtime/vm_operations.hpp" |
aoqi@0 | 56 | #include "services/memoryService.hpp" |
aoqi@0 | 57 | #include "utilities/stack.inline.hpp" |
aoqi@0 | 58 | |
aoqi@0 | 59 | PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC |
aoqi@0 | 60 | |
aoqi@0 | 61 | HeapWord* PSScavenge::_to_space_top_before_gc = NULL; |
aoqi@0 | 62 | int PSScavenge::_consecutive_skipped_scavenges = 0; |
aoqi@0 | 63 | ReferenceProcessor* PSScavenge::_ref_processor = NULL; |
aoqi@0 | 64 | CardTableExtension* PSScavenge::_card_table = NULL; |
aoqi@0 | 65 | bool PSScavenge::_survivor_overflow = false; |
aoqi@0 | 66 | uint PSScavenge::_tenuring_threshold = 0; |
aoqi@0 | 67 | HeapWord* PSScavenge::_young_generation_boundary = NULL; |
aoqi@0 | 68 | uintptr_t PSScavenge::_young_generation_boundary_compressed = 0; |
aoqi@0 | 69 | elapsedTimer PSScavenge::_accumulated_time; |
aoqi@0 | 70 | STWGCTimer PSScavenge::_gc_timer; |
aoqi@0 | 71 | ParallelScavengeTracer PSScavenge::_gc_tracer; |
aoqi@0 | 72 | Stack<markOop, mtGC> PSScavenge::_preserved_mark_stack; |
aoqi@0 | 73 | Stack<oop, mtGC> PSScavenge::_preserved_oop_stack; |
aoqi@0 | 74 | CollectorCounters* PSScavenge::_counters = NULL; |
aoqi@0 | 75 | |
aoqi@0 | 76 | // Define before use |
aoqi@0 | 77 | class PSIsAliveClosure: public BoolObjectClosure { |
aoqi@0 | 78 | public: |
aoqi@0 | 79 | bool do_object_b(oop p) { |
aoqi@0 | 80 | return (!PSScavenge::is_obj_in_young(p)) || p->is_forwarded(); |
aoqi@0 | 81 | } |
aoqi@0 | 82 | }; |
aoqi@0 | 83 | |
aoqi@0 | 84 | PSIsAliveClosure PSScavenge::_is_alive_closure; |
aoqi@0 | 85 | |
aoqi@0 | 86 | class PSKeepAliveClosure: public OopClosure { |
aoqi@0 | 87 | protected: |
aoqi@0 | 88 | MutableSpace* _to_space; |
aoqi@0 | 89 | PSPromotionManager* _promotion_manager; |
aoqi@0 | 90 | |
aoqi@0 | 91 | public: |
aoqi@0 | 92 | PSKeepAliveClosure(PSPromotionManager* pm) : _promotion_manager(pm) { |
aoqi@0 | 93 | ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); |
aoqi@0 | 94 | assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); |
aoqi@0 | 95 | _to_space = heap->young_gen()->to_space(); |
aoqi@0 | 96 | |
aoqi@0 | 97 | assert(_promotion_manager != NULL, "Sanity"); |
aoqi@0 | 98 | } |
aoqi@0 | 99 | |
aoqi@0 | 100 | template <class T> void do_oop_work(T* p) { |
aoqi@0 | 101 | assert (!oopDesc::is_null(*p), "expected non-null ref"); |
aoqi@0 | 102 | assert ((oopDesc::load_decode_heap_oop_not_null(p))->is_oop(), |
aoqi@0 | 103 | "expected an oop while scanning weak refs"); |
aoqi@0 | 104 | |
aoqi@0 | 105 | // Weak refs may be visited more than once. |
aoqi@0 | 106 | if (PSScavenge::should_scavenge(p, _to_space)) { |
aoqi@0 | 107 | PSScavenge::copy_and_push_safe_barrier<T, /*promote_immediately=*/false>(_promotion_manager, p); |
aoqi@0 | 108 | } |
aoqi@0 | 109 | } |
aoqi@0 | 110 | virtual void do_oop(oop* p) { PSKeepAliveClosure::do_oop_work(p); } |
aoqi@0 | 111 | virtual void do_oop(narrowOop* p) { PSKeepAliveClosure::do_oop_work(p); } |
aoqi@0 | 112 | }; |
aoqi@0 | 113 | |
aoqi@0 | 114 | class PSEvacuateFollowersClosure: public VoidClosure { |
aoqi@0 | 115 | private: |
aoqi@0 | 116 | PSPromotionManager* _promotion_manager; |
aoqi@0 | 117 | public: |
aoqi@0 | 118 | PSEvacuateFollowersClosure(PSPromotionManager* pm) : _promotion_manager(pm) {} |
aoqi@0 | 119 | |
aoqi@0 | 120 | virtual void do_void() { |
aoqi@0 | 121 | assert(_promotion_manager != NULL, "Sanity"); |
aoqi@0 | 122 | _promotion_manager->drain_stacks(true); |
aoqi@0 | 123 | guarantee(_promotion_manager->stacks_empty(), |
aoqi@0 | 124 | "stacks should be empty at this point"); |
aoqi@0 | 125 | } |
aoqi@0 | 126 | }; |
aoqi@0 | 127 | |
aoqi@0 | 128 | class PSPromotionFailedClosure : public ObjectClosure { |
aoqi@0 | 129 | virtual void do_object(oop obj) { |
aoqi@0 | 130 | if (obj->is_forwarded()) { |
aoqi@0 | 131 | obj->init_mark(); |
aoqi@0 | 132 | } |
aoqi@0 | 133 | } |
aoqi@0 | 134 | }; |
aoqi@0 | 135 | |
aoqi@0 | 136 | class PSRefProcTaskProxy: public GCTask { |
aoqi@0 | 137 | typedef AbstractRefProcTaskExecutor::ProcessTask ProcessTask; |
aoqi@0 | 138 | ProcessTask & _rp_task; |
aoqi@0 | 139 | uint _work_id; |
aoqi@0 | 140 | public: |
aoqi@0 | 141 | PSRefProcTaskProxy(ProcessTask & rp_task, uint work_id) |
aoqi@0 | 142 | : _rp_task(rp_task), |
aoqi@0 | 143 | _work_id(work_id) |
aoqi@0 | 144 | { } |
aoqi@0 | 145 | |
aoqi@0 | 146 | private: |
aoqi@0 | 147 | virtual char* name() { return (char *)"Process referents by policy in parallel"; } |
aoqi@0 | 148 | virtual void do_it(GCTaskManager* manager, uint which); |
aoqi@0 | 149 | }; |
aoqi@0 | 150 | |
aoqi@0 | 151 | void PSRefProcTaskProxy::do_it(GCTaskManager* manager, uint which) |
aoqi@0 | 152 | { |
aoqi@0 | 153 | PSPromotionManager* promotion_manager = |
aoqi@0 | 154 | PSPromotionManager::gc_thread_promotion_manager(which); |
aoqi@0 | 155 | assert(promotion_manager != NULL, "sanity check"); |
aoqi@0 | 156 | PSKeepAliveClosure keep_alive(promotion_manager); |
aoqi@0 | 157 | PSEvacuateFollowersClosure evac_followers(promotion_manager); |
aoqi@0 | 158 | PSIsAliveClosure is_alive; |
aoqi@0 | 159 | _rp_task.work(_work_id, is_alive, keep_alive, evac_followers); |
aoqi@0 | 160 | } |
aoqi@0 | 161 | |
aoqi@0 | 162 | class PSRefEnqueueTaskProxy: public GCTask { |
aoqi@0 | 163 | typedef AbstractRefProcTaskExecutor::EnqueueTask EnqueueTask; |
aoqi@0 | 164 | EnqueueTask& _enq_task; |
aoqi@0 | 165 | uint _work_id; |
aoqi@0 | 166 | |
aoqi@0 | 167 | public: |
aoqi@0 | 168 | PSRefEnqueueTaskProxy(EnqueueTask& enq_task, uint work_id) |
aoqi@0 | 169 | : _enq_task(enq_task), |
aoqi@0 | 170 | _work_id(work_id) |
aoqi@0 | 171 | { } |
aoqi@0 | 172 | |
aoqi@0 | 173 | virtual char* name() { return (char *)"Enqueue reference objects in parallel"; } |
aoqi@0 | 174 | virtual void do_it(GCTaskManager* manager, uint which) |
aoqi@0 | 175 | { |
aoqi@0 | 176 | _enq_task.work(_work_id); |
aoqi@0 | 177 | } |
aoqi@0 | 178 | }; |
aoqi@0 | 179 | |
aoqi@0 | 180 | class PSRefProcTaskExecutor: public AbstractRefProcTaskExecutor { |
aoqi@0 | 181 | virtual void execute(ProcessTask& task); |
aoqi@0 | 182 | virtual void execute(EnqueueTask& task); |
aoqi@0 | 183 | }; |
aoqi@0 | 184 | |
aoqi@0 | 185 | void PSRefProcTaskExecutor::execute(ProcessTask& task) |
aoqi@0 | 186 | { |
aoqi@0 | 187 | GCTaskQueue* q = GCTaskQueue::create(); |
aoqi@0 | 188 | GCTaskManager* manager = ParallelScavengeHeap::gc_task_manager(); |
aoqi@0 | 189 | for(uint i=0; i < manager->active_workers(); i++) { |
aoqi@0 | 190 | q->enqueue(new PSRefProcTaskProxy(task, i)); |
aoqi@0 | 191 | } |
aoqi@0 | 192 | ParallelTaskTerminator terminator(manager->active_workers(), |
aoqi@0 | 193 | (TaskQueueSetSuper*) PSPromotionManager::stack_array_depth()); |
aoqi@0 | 194 | if (task.marks_oops_alive() && manager->active_workers() > 1) { |
aoqi@0 | 195 | for (uint j = 0; j < manager->active_workers(); j++) { |
aoqi@0 | 196 | q->enqueue(new StealTask(&terminator)); |
aoqi@0 | 197 | } |
aoqi@0 | 198 | } |
aoqi@0 | 199 | manager->execute_and_wait(q); |
aoqi@0 | 200 | } |
aoqi@0 | 201 | |
aoqi@0 | 202 | |
aoqi@0 | 203 | void PSRefProcTaskExecutor::execute(EnqueueTask& task) |
aoqi@0 | 204 | { |
aoqi@0 | 205 | GCTaskQueue* q = GCTaskQueue::create(); |
aoqi@0 | 206 | GCTaskManager* manager = ParallelScavengeHeap::gc_task_manager(); |
aoqi@0 | 207 | for(uint i=0; i < manager->active_workers(); i++) { |
aoqi@0 | 208 | q->enqueue(new PSRefEnqueueTaskProxy(task, i)); |
aoqi@0 | 209 | } |
aoqi@0 | 210 | manager->execute_and_wait(q); |
aoqi@0 | 211 | } |
aoqi@0 | 212 | |
aoqi@0 | 213 | // This method contains all heap specific policy for invoking scavenge. |
aoqi@0 | 214 | // PSScavenge::invoke_no_policy() will do nothing but attempt to |
aoqi@0 | 215 | // scavenge. It will not clean up after failed promotions, bail out if |
aoqi@0 | 216 | // we've exceeded policy time limits, or any other special behavior. |
aoqi@0 | 217 | // All such policy should be placed here. |
aoqi@0 | 218 | // |
aoqi@0 | 219 | // Note that this method should only be called from the vm_thread while |
aoqi@0 | 220 | // at a safepoint! |
aoqi@0 | 221 | bool PSScavenge::invoke() { |
aoqi@0 | 222 | assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); |
aoqi@0 | 223 | assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); |
aoqi@0 | 224 | assert(!Universe::heap()->is_gc_active(), "not reentrant"); |
aoqi@0 | 225 | |
aoqi@0 | 226 | ParallelScavengeHeap* const heap = (ParallelScavengeHeap*)Universe::heap(); |
aoqi@0 | 227 | assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); |
aoqi@0 | 228 | |
aoqi@0 | 229 | PSAdaptiveSizePolicy* policy = heap->size_policy(); |
aoqi@0 | 230 | IsGCActiveMark mark; |
aoqi@0 | 231 | |
aoqi@0 | 232 | const bool scavenge_done = PSScavenge::invoke_no_policy(); |
aoqi@25 | 233 | const bool need_full_gc = !scavenge_done || |
aoqi@25 | 234 | policy->should_full_GC(heap->old_gen()->free_in_bytes()); |
aoqi@0 | 235 | bool full_gc_done = false; |
aoqi@0 | 236 | |
aoqi@0 | 237 | if (UsePerfData) { |
aoqi@0 | 238 | PSGCAdaptivePolicyCounters* const counters = heap->gc_policy_counters(); |
aoqi@0 | 239 | const int ffs_val = need_full_gc ? full_follows_scavenge : not_skipped; |
aoqi@0 | 240 | counters->update_full_follows_scavenge(ffs_val); |
aoqi@0 | 241 | } |
aoqi@0 | 242 | |
aoqi@0 | 243 | if (need_full_gc) { |
aoqi@0 | 244 | GCCauseSetter gccs(heap, GCCause::_adaptive_size_policy); |
aoqi@0 | 245 | CollectorPolicy* cp = heap->collector_policy(); |
aoqi@0 | 246 | const bool clear_all_softrefs = cp->should_clear_all_soft_refs(); |
aoqi@0 | 247 | |
aoqi@0 | 248 | if (UseParallelOldGC) { |
aoqi@0 | 249 | full_gc_done = PSParallelCompact::invoke_no_policy(clear_all_softrefs); |
aoqi@0 | 250 | } else { |
aoqi@0 | 251 | full_gc_done = PSMarkSweep::invoke_no_policy(clear_all_softrefs); |
aoqi@0 | 252 | } |
aoqi@0 | 253 | } |
aoqi@0 | 254 | |
aoqi@0 | 255 | return full_gc_done; |
aoqi@0 | 256 | } |
aoqi@0 | 257 | |
aoqi@0 | 258 | // This method contains no policy. You should probably |
aoqi@0 | 259 | // be calling invoke() instead. |
aoqi@0 | 260 | bool PSScavenge::invoke_no_policy() { |
aoqi@0 | 261 | assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); |
aoqi@0 | 262 | assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); |
aoqi@0 | 263 | |
aoqi@0 | 264 | assert(_preserved_mark_stack.is_empty(), "should be empty"); |
aoqi@0 | 265 | assert(_preserved_oop_stack.is_empty(), "should be empty"); |
aoqi@0 | 266 | |
aoqi@0 | 267 | _gc_timer.register_gc_start(); |
aoqi@0 | 268 | |
aoqi@0 | 269 | TimeStamp scavenge_entry; |
aoqi@0 | 270 | TimeStamp scavenge_midpoint; |
aoqi@0 | 271 | TimeStamp scavenge_exit; |
aoqi@0 | 272 | |
aoqi@0 | 273 | scavenge_entry.update(); |
aoqi@0 | 274 | |
aoqi@0 | 275 | if (GC_locker::check_active_before_gc()) { |
aoqi@0 | 276 | return false; |
aoqi@0 | 277 | } |
aoqi@0 | 278 | |
aoqi@0 | 279 | ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); |
aoqi@0 | 280 | GCCause::Cause gc_cause = heap->gc_cause(); |
aoqi@0 | 281 | assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); |
aoqi@0 | 282 | |
aoqi@0 | 283 | // Check for potential problems. |
aoqi@0 | 284 | if (!should_attempt_scavenge()) { |
aoqi@0 | 285 | return false; |
aoqi@0 | 286 | } |
aoqi@0 | 287 | |
aoqi@0 | 288 | _gc_tracer.report_gc_start(heap->gc_cause(), _gc_timer.gc_start()); |
aoqi@0 | 289 | |
aoqi@0 | 290 | bool promotion_failure_occurred = false; |
aoqi@0 | 291 | |
aoqi@0 | 292 | PSYoungGen* young_gen = heap->young_gen(); |
aoqi@0 | 293 | PSOldGen* old_gen = heap->old_gen(); |
aoqi@0 | 294 | PSAdaptiveSizePolicy* size_policy = heap->size_policy(); |
aoqi@0 | 295 | |
aoqi@0 | 296 | heap->increment_total_collections(); |
aoqi@0 | 297 | |
aoqi@0 | 298 | AdaptiveSizePolicyOutput(size_policy, heap->total_collections()); |
aoqi@0 | 299 | |
aoqi@0 | 300 | if ((gc_cause != GCCause::_java_lang_system_gc) || |
aoqi@0 | 301 | UseAdaptiveSizePolicyWithSystemGC) { |
aoqi@0 | 302 | // Gather the feedback data for eden occupancy. |
aoqi@0 | 303 | young_gen->eden_space()->accumulate_statistics(); |
aoqi@0 | 304 | } |
aoqi@0 | 305 | |
aoqi@0 | 306 | if (ZapUnusedHeapArea) { |
aoqi@0 | 307 | // Save information needed to minimize mangling |
aoqi@0 | 308 | heap->record_gen_tops_before_GC(); |
aoqi@0 | 309 | } |
aoqi@0 | 310 | |
aoqi@0 | 311 | heap->print_heap_before_gc(); |
aoqi@0 | 312 | heap->trace_heap_before_gc(&_gc_tracer); |
aoqi@0 | 313 | |
aoqi@0 | 314 | assert(!NeverTenure || _tenuring_threshold == markOopDesc::max_age + 1, "Sanity"); |
aoqi@0 | 315 | assert(!AlwaysTenure || _tenuring_threshold == 0, "Sanity"); |
aoqi@0 | 316 | |
aoqi@0 | 317 | size_t prev_used = heap->used(); |
aoqi@0 | 318 | |
aoqi@0 | 319 | // Fill in TLABs |
aoqi@0 | 320 | heap->accumulate_statistics_all_tlabs(); |
aoqi@0 | 321 | heap->ensure_parsability(true); // retire TLABs |
aoqi@0 | 322 | |
aoqi@0 | 323 | if (VerifyBeforeGC && heap->total_collections() >= VerifyGCStartAt) { |
aoqi@0 | 324 | HandleMark hm; // Discard invalid handles created during verification |
aoqi@0 | 325 | Universe::verify(" VerifyBeforeGC:"); |
aoqi@0 | 326 | } |
aoqi@0 | 327 | |
aoqi@0 | 328 | { |
aoqi@0 | 329 | ResourceMark rm; |
aoqi@0 | 330 | HandleMark hm; |
aoqi@0 | 331 | |
aoqi@0 | 332 | gclog_or_tty->date_stamp(PrintGC && PrintGCDateStamps); |
aoqi@0 | 333 | TraceCPUTime tcpu(PrintGCDetails, true, gclog_or_tty); |
aoqi@0 | 334 | GCTraceTime t1(GCCauseString("GC", gc_cause), PrintGC, !PrintGCDetails, NULL); |
aoqi@0 | 335 | TraceCollectorStats tcs(counters()); |
aoqi@0 | 336 | TraceMemoryManagerStats tms(false /* not full GC */,gc_cause); |
aoqi@0 | 337 | |
aoqi@0 | 338 | if (TraceGen0Time) accumulated_time()->start(); |
aoqi@0 | 339 | |
aoqi@0 | 340 | // Let the size policy know we're starting |
aoqi@0 | 341 | size_policy->minor_collection_begin(); |
aoqi@0 | 342 | |
aoqi@0 | 343 | // Verify the object start arrays. |
aoqi@0 | 344 | if (VerifyObjectStartArray && |
aoqi@0 | 345 | VerifyBeforeGC) { |
aoqi@0 | 346 | old_gen->verify_object_start_array(); |
aoqi@0 | 347 | } |
aoqi@0 | 348 | |
aoqi@0 | 349 | // Verify no unmarked old->young roots |
aoqi@0 | 350 | if (VerifyRememberedSets) { |
aoqi@0 | 351 | CardTableExtension::verify_all_young_refs_imprecise(); |
aoqi@0 | 352 | } |
aoqi@0 | 353 | |
aoqi@0 | 354 | if (!ScavengeWithObjectsInToSpace) { |
aoqi@0 | 355 | assert(young_gen->to_space()->is_empty(), |
aoqi@0 | 356 | "Attempt to scavenge with live objects in to_space"); |
aoqi@0 | 357 | young_gen->to_space()->clear(SpaceDecorator::Mangle); |
aoqi@0 | 358 | } else if (ZapUnusedHeapArea) { |
aoqi@0 | 359 | young_gen->to_space()->mangle_unused_area(); |
aoqi@0 | 360 | } |
aoqi@0 | 361 | save_to_space_top_before_gc(); |
aoqi@0 | 362 | |
aoqi@0 | 363 | COMPILER2_PRESENT(DerivedPointerTable::clear()); |
aoqi@0 | 364 | |
aoqi@0 | 365 | reference_processor()->enable_discovery(true /*verify_disabled*/, true /*verify_no_refs*/); |
aoqi@0 | 366 | reference_processor()->setup_policy(false); |
aoqi@0 | 367 | |
aoqi@0 | 368 | // We track how much was promoted to the next generation for |
aoqi@0 | 369 | // the AdaptiveSizePolicy. |
aoqi@0 | 370 | size_t old_gen_used_before = old_gen->used_in_bytes(); |
aoqi@0 | 371 | |
aoqi@0 | 372 | // For PrintGCDetails |
aoqi@0 | 373 | size_t young_gen_used_before = young_gen->used_in_bytes(); |
aoqi@0 | 374 | |
aoqi@0 | 375 | // Reset our survivor overflow. |
aoqi@0 | 376 | set_survivor_overflow(false); |
aoqi@0 | 377 | |
aoqi@0 | 378 | // We need to save the old top values before |
aoqi@0 | 379 | // creating the promotion_manager. We pass the top |
aoqi@0 | 380 | // values to the card_table, to prevent it from |
aoqi@0 | 381 | // straying into the promotion labs. |
aoqi@0 | 382 | HeapWord* old_top = old_gen->object_space()->top(); |
aoqi@0 | 383 | |
aoqi@0 | 384 | // Release all previously held resources |
aoqi@0 | 385 | gc_task_manager()->release_all_resources(); |
aoqi@0 | 386 | |
aoqi@0 | 387 | // Set the number of GC threads to be used in this collection |
aoqi@0 | 388 | gc_task_manager()->set_active_gang(); |
aoqi@0 | 389 | gc_task_manager()->task_idle_workers(); |
aoqi@0 | 390 | // Get the active number of workers here and use that value |
aoqi@0 | 391 | // throughout the methods. |
aoqi@0 | 392 | uint active_workers = gc_task_manager()->active_workers(); |
aoqi@0 | 393 | heap->set_par_threads(active_workers); |
aoqi@0 | 394 | |
aoqi@0 | 395 | PSPromotionManager::pre_scavenge(); |
aoqi@0 | 396 | |
aoqi@0 | 397 | // We'll use the promotion manager again later. |
aoqi@0 | 398 | PSPromotionManager* promotion_manager = PSPromotionManager::vm_thread_promotion_manager(); |
aoqi@0 | 399 | { |
aoqi@0 | 400 | GCTraceTime tm("Scavenge", false, false, &_gc_timer); |
aoqi@0 | 401 | ParallelScavengeHeap::ParStrongRootsScope psrs; |
aoqi@0 | 402 | |
aoqi@0 | 403 | GCTaskQueue* q = GCTaskQueue::create(); |
aoqi@0 | 404 | |
aoqi@25 | 405 | if (!old_gen->object_space()->is_empty()) { |
aoqi@25 | 406 | // There are only old-to-young pointers if there are objects |
aoqi@25 | 407 | // in the old gen. |
aoqi@25 | 408 | uint stripe_total = active_workers; |
aoqi@25 | 409 | for(uint i=0; i < stripe_total; i++) { |
aoqi@25 | 410 | q->enqueue(new OldToYoungRootsTask(old_gen, old_top, i, stripe_total)); |
aoqi@0 | 411 | } |
aoqi@0 | 412 | } |
aoqi@0 | 413 | |
aoqi@0 | 414 | q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::universe)); |
aoqi@0 | 415 | q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::jni_handles)); |
aoqi@0 | 416 | // We scan the thread roots in parallel |
aoqi@0 | 417 | Threads::create_thread_roots_tasks(q); |
aoqi@0 | 418 | q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::object_synchronizer)); |
aoqi@0 | 419 | q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::flat_profiler)); |
aoqi@0 | 420 | q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::management)); |
aoqi@0 | 421 | q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::system_dictionary)); |
aoqi@0 | 422 | q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::class_loader_data)); |
aoqi@0 | 423 | q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::jvmti)); |
aoqi@0 | 424 | q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::code_cache)); |
aoqi@0 | 425 | |
aoqi@0 | 426 | ParallelTaskTerminator terminator( |
aoqi@0 | 427 | active_workers, |
aoqi@0 | 428 | (TaskQueueSetSuper*) promotion_manager->stack_array_depth()); |
aoqi@0 | 429 | if (active_workers > 1) { |
aoqi@0 | 430 | for (uint j = 0; j < active_workers; j++) { |
aoqi@0 | 431 | q->enqueue(new StealTask(&terminator)); |
aoqi@0 | 432 | } |
aoqi@0 | 433 | } |
aoqi@0 | 434 | |
aoqi@0 | 435 | gc_task_manager()->execute_and_wait(q); |
aoqi@0 | 436 | } |
aoqi@0 | 437 | |
aoqi@0 | 438 | scavenge_midpoint.update(); |
aoqi@0 | 439 | |
aoqi@0 | 440 | // Process reference objects discovered during scavenge |
aoqi@0 | 441 | { |
aoqi@0 | 442 | GCTraceTime tm("References", false, false, &_gc_timer); |
aoqi@0 | 443 | |
aoqi@0 | 444 | reference_processor()->setup_policy(false); // not always_clear |
aoqi@0 | 445 | reference_processor()->set_active_mt_degree(active_workers); |
aoqi@0 | 446 | PSKeepAliveClosure keep_alive(promotion_manager); |
aoqi@0 | 447 | PSEvacuateFollowersClosure evac_followers(promotion_manager); |
aoqi@0 | 448 | ReferenceProcessorStats stats; |
aoqi@0 | 449 | if (reference_processor()->processing_is_mt()) { |
aoqi@0 | 450 | PSRefProcTaskExecutor task_executor; |
aoqi@0 | 451 | stats = reference_processor()->process_discovered_references( |
aoqi@0 | 452 | &_is_alive_closure, &keep_alive, &evac_followers, &task_executor, |
aoqi@0 | 453 | &_gc_timer); |
aoqi@0 | 454 | } else { |
aoqi@0 | 455 | stats = reference_processor()->process_discovered_references( |
aoqi@0 | 456 | &_is_alive_closure, &keep_alive, &evac_followers, NULL, &_gc_timer); |
aoqi@0 | 457 | } |
aoqi@0 | 458 | |
aoqi@0 | 459 | _gc_tracer.report_gc_reference_stats(stats); |
aoqi@0 | 460 | |
aoqi@0 | 461 | // Enqueue reference objects discovered during scavenge. |
aoqi@0 | 462 | if (reference_processor()->processing_is_mt()) { |
aoqi@0 | 463 | PSRefProcTaskExecutor task_executor; |
aoqi@0 | 464 | reference_processor()->enqueue_discovered_references(&task_executor); |
aoqi@0 | 465 | } else { |
aoqi@0 | 466 | reference_processor()->enqueue_discovered_references(NULL); |
aoqi@0 | 467 | } |
aoqi@0 | 468 | } |
aoqi@0 | 469 | |
aoqi@0 | 470 | { |
aoqi@0 | 471 | GCTraceTime tm("StringTable", false, false, &_gc_timer); |
aoqi@0 | 472 | // Unlink any dead interned Strings and process the remaining live ones. |
aoqi@0 | 473 | PSScavengeRootsClosure root_closure(promotion_manager); |
aoqi@0 | 474 | StringTable::unlink_or_oops_do(&_is_alive_closure, &root_closure); |
aoqi@0 | 475 | } |
aoqi@0 | 476 | |
aoqi@0 | 477 | // Finally, flush the promotion_manager's labs, and deallocate its stacks. |
aoqi@0 | 478 | promotion_failure_occurred = PSPromotionManager::post_scavenge(_gc_tracer); |
aoqi@0 | 479 | if (promotion_failure_occurred) { |
aoqi@0 | 480 | clean_up_failed_promotion(); |
aoqi@0 | 481 | if (PrintGC) { |
aoqi@0 | 482 | gclog_or_tty->print("--"); |
aoqi@0 | 483 | } |
aoqi@0 | 484 | } |
aoqi@0 | 485 | |
aoqi@0 | 486 | // Let the size policy know we're done. Note that we count promotion |
aoqi@0 | 487 | // failure cleanup time as part of the collection (otherwise, we're |
aoqi@0 | 488 | // implicitly saying it's mutator time). |
aoqi@0 | 489 | size_policy->minor_collection_end(gc_cause); |
aoqi@0 | 490 | |
aoqi@0 | 491 | if (!promotion_failure_occurred) { |
aoqi@0 | 492 | // Swap the survivor spaces. |
aoqi@0 | 493 | young_gen->eden_space()->clear(SpaceDecorator::Mangle); |
aoqi@0 | 494 | young_gen->from_space()->clear(SpaceDecorator::Mangle); |
aoqi@0 | 495 | young_gen->swap_spaces(); |
aoqi@0 | 496 | |
aoqi@0 | 497 | size_t survived = young_gen->from_space()->used_in_bytes(); |
aoqi@0 | 498 | size_t promoted = old_gen->used_in_bytes() - old_gen_used_before; |
aoqi@0 | 499 | size_policy->update_averages(_survivor_overflow, survived, promoted); |
aoqi@0 | 500 | |
aoqi@0 | 501 | // A successful scavenge should restart the GC time limit count which is |
aoqi@0 | 502 | // for full GC's. |
aoqi@0 | 503 | size_policy->reset_gc_overhead_limit_count(); |
aoqi@0 | 504 | if (UseAdaptiveSizePolicy) { |
aoqi@0 | 505 | // Calculate the new survivor size and tenuring threshold |
aoqi@0 | 506 | |
aoqi@0 | 507 | if (PrintAdaptiveSizePolicy) { |
aoqi@0 | 508 | gclog_or_tty->print("AdaptiveSizeStart: "); |
aoqi@0 | 509 | gclog_or_tty->stamp(); |
aoqi@0 | 510 | gclog_or_tty->print_cr(" collection: %d ", |
aoqi@0 | 511 | heap->total_collections()); |
aoqi@0 | 512 | |
aoqi@0 | 513 | if (Verbose) { |
aoqi@0 | 514 | gclog_or_tty->print("old_gen_capacity: %d young_gen_capacity: %d", |
aoqi@0 | 515 | old_gen->capacity_in_bytes(), young_gen->capacity_in_bytes()); |
aoqi@0 | 516 | } |
aoqi@0 | 517 | } |
aoqi@0 | 518 | |
aoqi@0 | 519 | |
aoqi@0 | 520 | if (UsePerfData) { |
aoqi@0 | 521 | PSGCAdaptivePolicyCounters* counters = heap->gc_policy_counters(); |
aoqi@0 | 522 | counters->update_old_eden_size( |
aoqi@0 | 523 | size_policy->calculated_eden_size_in_bytes()); |
aoqi@0 | 524 | counters->update_old_promo_size( |
aoqi@0 | 525 | size_policy->calculated_promo_size_in_bytes()); |
aoqi@0 | 526 | counters->update_old_capacity(old_gen->capacity_in_bytes()); |
aoqi@0 | 527 | counters->update_young_capacity(young_gen->capacity_in_bytes()); |
aoqi@0 | 528 | counters->update_survived(survived); |
aoqi@0 | 529 | counters->update_promoted(promoted); |
aoqi@0 | 530 | counters->update_survivor_overflowed(_survivor_overflow); |
aoqi@0 | 531 | } |
aoqi@0 | 532 | |
aoqi@0 | 533 | size_t max_young_size = young_gen->max_size(); |
aoqi@0 | 534 | |
aoqi@0 | 535 | // Deciding a free ratio in the young generation is tricky, so if |
aoqi@0 | 536 | // MinHeapFreeRatio or MaxHeapFreeRatio are in use (implicating |
aoqi@0 | 537 | // that the old generation size may have been limited because of them) we |
aoqi@0 | 538 | // should then limit our young generation size using NewRatio to have it |
aoqi@0 | 539 | // follow the old generation size. |
aoqi@0 | 540 | if (MinHeapFreeRatio != 0 || MaxHeapFreeRatio != 100) { |
aoqi@0 | 541 | max_young_size = MIN2(old_gen->capacity_in_bytes() / NewRatio, young_gen->max_size()); |
aoqi@0 | 542 | } |
aoqi@0 | 543 | |
aoqi@0 | 544 | size_t survivor_limit = |
aoqi@0 | 545 | size_policy->max_survivor_size(max_young_size); |
aoqi@0 | 546 | _tenuring_threshold = |
aoqi@0 | 547 | size_policy->compute_survivor_space_size_and_threshold( |
aoqi@0 | 548 | _survivor_overflow, |
aoqi@0 | 549 | _tenuring_threshold, |
aoqi@0 | 550 | survivor_limit); |
aoqi@0 | 551 | |
aoqi@0 | 552 | if (PrintTenuringDistribution) { |
aoqi@0 | 553 | gclog_or_tty->cr(); |
aoqi@0 | 554 | gclog_or_tty->print_cr("Desired survivor size " SIZE_FORMAT " bytes, new threshold %u (max %u)", |
aoqi@0 | 555 | size_policy->calculated_survivor_size_in_bytes(), |
aoqi@0 | 556 | _tenuring_threshold, MaxTenuringThreshold); |
aoqi@0 | 557 | } |
aoqi@0 | 558 | |
aoqi@0 | 559 | if (UsePerfData) { |
aoqi@0 | 560 | PSGCAdaptivePolicyCounters* counters = heap->gc_policy_counters(); |
aoqi@0 | 561 | counters->update_tenuring_threshold(_tenuring_threshold); |
aoqi@0 | 562 | counters->update_survivor_size_counters(); |
aoqi@0 | 563 | } |
aoqi@0 | 564 | |
aoqi@0 | 565 | // Do call at minor collections? |
aoqi@0 | 566 | // Don't check if the size_policy is ready at this |
aoqi@0 | 567 | // level. Let the size_policy check that internally. |
aoqi@0 | 568 | if (UseAdaptiveGenerationSizePolicyAtMinorCollection && |
aoqi@0 | 569 | ((gc_cause != GCCause::_java_lang_system_gc) || |
aoqi@0 | 570 | UseAdaptiveSizePolicyWithSystemGC)) { |
aoqi@0 | 571 | |
aoqi@0 | 572 | // Calculate optimial free space amounts |
aoqi@0 | 573 | assert(young_gen->max_size() > |
aoqi@0 | 574 | young_gen->from_space()->capacity_in_bytes() + |
aoqi@0 | 575 | young_gen->to_space()->capacity_in_bytes(), |
aoqi@0 | 576 | "Sizes of space in young gen are out-of-bounds"); |
aoqi@0 | 577 | |
aoqi@0 | 578 | size_t young_live = young_gen->used_in_bytes(); |
aoqi@0 | 579 | size_t eden_live = young_gen->eden_space()->used_in_bytes(); |
aoqi@0 | 580 | size_t cur_eden = young_gen->eden_space()->capacity_in_bytes(); |
aoqi@0 | 581 | size_t max_old_gen_size = old_gen->max_gen_size(); |
aoqi@0 | 582 | size_t max_eden_size = max_young_size - |
aoqi@0 | 583 | young_gen->from_space()->capacity_in_bytes() - |
aoqi@0 | 584 | young_gen->to_space()->capacity_in_bytes(); |
aoqi@0 | 585 | |
aoqi@0 | 586 | // Used for diagnostics |
aoqi@0 | 587 | size_policy->clear_generation_free_space_flags(); |
aoqi@0 | 588 | |
aoqi@0 | 589 | size_policy->compute_eden_space_size(young_live, |
aoqi@0 | 590 | eden_live, |
aoqi@0 | 591 | cur_eden, |
aoqi@0 | 592 | max_eden_size, |
aoqi@0 | 593 | false /* not full gc*/); |
aoqi@0 | 594 | |
aoqi@0 | 595 | size_policy->check_gc_overhead_limit(young_live, |
aoqi@0 | 596 | eden_live, |
aoqi@0 | 597 | max_old_gen_size, |
aoqi@0 | 598 | max_eden_size, |
aoqi@0 | 599 | false /* not full gc*/, |
aoqi@0 | 600 | gc_cause, |
aoqi@0 | 601 | heap->collector_policy()); |
aoqi@0 | 602 | |
aoqi@0 | 603 | size_policy->decay_supplemental_growth(false /* not full gc*/); |
aoqi@0 | 604 | } |
aoqi@0 | 605 | // Resize the young generation at every collection |
aoqi@0 | 606 | // even if new sizes have not been calculated. This is |
aoqi@0 | 607 | // to allow resizes that may have been inhibited by the |
aoqi@0 | 608 | // relative location of the "to" and "from" spaces. |
aoqi@0 | 609 | |
aoqi@0 | 610 | // Resizing the old gen at minor collects can cause increases |
aoqi@0 | 611 | // that don't feed back to the generation sizing policy until |
aoqi@0 | 612 | // a major collection. Don't resize the old gen here. |
aoqi@0 | 613 | |
aoqi@0 | 614 | heap->resize_young_gen(size_policy->calculated_eden_size_in_bytes(), |
aoqi@0 | 615 | size_policy->calculated_survivor_size_in_bytes()); |
aoqi@0 | 616 | |
aoqi@0 | 617 | if (PrintAdaptiveSizePolicy) { |
aoqi@0 | 618 | gclog_or_tty->print_cr("AdaptiveSizeStop: collection: %d ", |
aoqi@0 | 619 | heap->total_collections()); |
aoqi@0 | 620 | } |
aoqi@0 | 621 | } |
aoqi@0 | 622 | |
aoqi@0 | 623 | // Update the structure of the eden. With NUMA-eden CPU hotplugging or offlining can |
aoqi@0 | 624 | // cause the change of the heap layout. Make sure eden is reshaped if that's the case. |
aoqi@0 | 625 | // Also update() will case adaptive NUMA chunk resizing. |
aoqi@0 | 626 | assert(young_gen->eden_space()->is_empty(), "eden space should be empty now"); |
aoqi@0 | 627 | young_gen->eden_space()->update(); |
aoqi@0 | 628 | |
aoqi@0 | 629 | heap->gc_policy_counters()->update_counters(); |
aoqi@0 | 630 | |
aoqi@0 | 631 | heap->resize_all_tlabs(); |
aoqi@0 | 632 | |
aoqi@0 | 633 | assert(young_gen->to_space()->is_empty(), "to space should be empty now"); |
aoqi@0 | 634 | } |
aoqi@0 | 635 | |
aoqi@0 | 636 | COMPILER2_PRESENT(DerivedPointerTable::update_pointers()); |
aoqi@0 | 637 | |
aoqi@0 | 638 | NOT_PRODUCT(reference_processor()->verify_no_references_recorded()); |
aoqi@0 | 639 | |
aoqi@0 | 640 | { |
aoqi@0 | 641 | GCTraceTime tm("Prune Scavenge Root Methods", false, false, &_gc_timer); |
aoqi@0 | 642 | |
aoqi@0 | 643 | CodeCache::prune_scavenge_root_nmethods(); |
aoqi@0 | 644 | } |
aoqi@0 | 645 | |
aoqi@0 | 646 | // Re-verify object start arrays |
aoqi@0 | 647 | if (VerifyObjectStartArray && |
aoqi@0 | 648 | VerifyAfterGC) { |
aoqi@0 | 649 | old_gen->verify_object_start_array(); |
aoqi@0 | 650 | } |
aoqi@0 | 651 | |
aoqi@0 | 652 | // Verify all old -> young cards are now precise |
aoqi@0 | 653 | if (VerifyRememberedSets) { |
aoqi@0 | 654 | // Precise verification will give false positives. Until this is fixed, |
aoqi@0 | 655 | // use imprecise verification. |
aoqi@0 | 656 | // CardTableExtension::verify_all_young_refs_precise(); |
aoqi@0 | 657 | CardTableExtension::verify_all_young_refs_imprecise(); |
aoqi@0 | 658 | } |
aoqi@0 | 659 | |
aoqi@0 | 660 | if (TraceGen0Time) accumulated_time()->stop(); |
aoqi@0 | 661 | |
aoqi@0 | 662 | if (PrintGC) { |
aoqi@0 | 663 | if (PrintGCDetails) { |
aoqi@0 | 664 | // Don't print a GC timestamp here. This is after the GC so |
aoqi@0 | 665 | // would be confusing. |
aoqi@0 | 666 | young_gen->print_used_change(young_gen_used_before); |
aoqi@0 | 667 | } |
aoqi@0 | 668 | heap->print_heap_change(prev_used); |
aoqi@0 | 669 | } |
aoqi@0 | 670 | |
aoqi@0 | 671 | // Track memory usage and detect low memory |
aoqi@0 | 672 | MemoryService::track_memory_usage(); |
aoqi@0 | 673 | heap->update_counters(); |
aoqi@0 | 674 | |
aoqi@0 | 675 | gc_task_manager()->release_idle_workers(); |
aoqi@0 | 676 | } |
aoqi@0 | 677 | |
aoqi@0 | 678 | if (VerifyAfterGC && heap->total_collections() >= VerifyGCStartAt) { |
aoqi@0 | 679 | HandleMark hm; // Discard invalid handles created during verification |
aoqi@0 | 680 | Universe::verify(" VerifyAfterGC:"); |
aoqi@0 | 681 | } |
aoqi@0 | 682 | |
aoqi@0 | 683 | heap->print_heap_after_gc(); |
aoqi@0 | 684 | heap->trace_heap_after_gc(&_gc_tracer); |
aoqi@0 | 685 | _gc_tracer.report_tenuring_threshold(tenuring_threshold()); |
aoqi@0 | 686 | |
aoqi@0 | 687 | if (ZapUnusedHeapArea) { |
aoqi@0 | 688 | young_gen->eden_space()->check_mangled_unused_area_complete(); |
aoqi@0 | 689 | young_gen->from_space()->check_mangled_unused_area_complete(); |
aoqi@0 | 690 | young_gen->to_space()->check_mangled_unused_area_complete(); |
aoqi@0 | 691 | } |
aoqi@0 | 692 | |
aoqi@0 | 693 | scavenge_exit.update(); |
aoqi@0 | 694 | |
aoqi@0 | 695 | if (PrintGCTaskTimeStamps) { |
aoqi@0 | 696 | tty->print_cr("VM-Thread " INT64_FORMAT " " INT64_FORMAT " " INT64_FORMAT, |
aoqi@0 | 697 | scavenge_entry.ticks(), scavenge_midpoint.ticks(), |
aoqi@0 | 698 | scavenge_exit.ticks()); |
aoqi@0 | 699 | gc_task_manager()->print_task_time_stamps(); |
aoqi@0 | 700 | } |
aoqi@0 | 701 | |
aoqi@0 | 702 | #ifdef TRACESPINNING |
aoqi@0 | 703 | ParallelTaskTerminator::print_termination_counts(); |
aoqi@0 | 704 | #endif |
aoqi@0 | 705 | |
aoqi@0 | 706 | |
aoqi@0 | 707 | _gc_timer.register_gc_end(); |
aoqi@0 | 708 | |
aoqi@0 | 709 | _gc_tracer.report_gc_end(_gc_timer.gc_end(), _gc_timer.time_partitions()); |
aoqi@0 | 710 | |
aoqi@0 | 711 | return !promotion_failure_occurred; |
aoqi@0 | 712 | } |
aoqi@0 | 713 | |
aoqi@0 | 714 | // This method iterates over all objects in the young generation, |
aoqi@0 | 715 | // unforwarding markOops. It then restores any preserved mark oops, |
aoqi@0 | 716 | // and clears the _preserved_mark_stack. |
aoqi@0 | 717 | void PSScavenge::clean_up_failed_promotion() { |
aoqi@0 | 718 | ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); |
aoqi@0 | 719 | assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); |
aoqi@0 | 720 | |
aoqi@0 | 721 | PSYoungGen* young_gen = heap->young_gen(); |
aoqi@0 | 722 | |
aoqi@0 | 723 | { |
aoqi@0 | 724 | ResourceMark rm; |
aoqi@0 | 725 | |
aoqi@0 | 726 | // Unforward all pointers in the young gen. |
aoqi@0 | 727 | PSPromotionFailedClosure unforward_closure; |
aoqi@0 | 728 | young_gen->object_iterate(&unforward_closure); |
aoqi@0 | 729 | |
aoqi@0 | 730 | if (PrintGC && Verbose) { |
aoqi@0 | 731 | gclog_or_tty->print_cr("Restoring %d marks", _preserved_oop_stack.size()); |
aoqi@0 | 732 | } |
aoqi@0 | 733 | |
aoqi@0 | 734 | // Restore any saved marks. |
aoqi@0 | 735 | while (!_preserved_oop_stack.is_empty()) { |
aoqi@0 | 736 | oop obj = _preserved_oop_stack.pop(); |
aoqi@0 | 737 | markOop mark = _preserved_mark_stack.pop(); |
aoqi@0 | 738 | obj->set_mark(mark); |
aoqi@0 | 739 | } |
aoqi@0 | 740 | |
aoqi@0 | 741 | // Clear the preserved mark and oop stack caches. |
aoqi@0 | 742 | _preserved_mark_stack.clear(true); |
aoqi@0 | 743 | _preserved_oop_stack.clear(true); |
aoqi@0 | 744 | } |
aoqi@0 | 745 | |
aoqi@0 | 746 | // Reset the PromotionFailureALot counters. |
aoqi@0 | 747 | NOT_PRODUCT(Universe::heap()->reset_promotion_should_fail();) |
aoqi@0 | 748 | } |
aoqi@0 | 749 | |
aoqi@0 | 750 | // This method is called whenever an attempt to promote an object |
aoqi@0 | 751 | // fails. Some markOops will need preservation, some will not. Note |
aoqi@0 | 752 | // that the entire eden is traversed after a failed promotion, with |
aoqi@0 | 753 | // all forwarded headers replaced by the default markOop. This means |
aoqi@0 | 754 | // it is not necessary to preserve most markOops. |
aoqi@0 | 755 | void PSScavenge::oop_promotion_failed(oop obj, markOop obj_mark) { |
aoqi@0 | 756 | if (obj_mark->must_be_preserved_for_promotion_failure(obj)) { |
aoqi@0 | 757 | // Should use per-worker private stacks here rather than |
aoqi@0 | 758 | // locking a common pair of stacks. |
aoqi@0 | 759 | ThreadCritical tc; |
aoqi@0 | 760 | _preserved_oop_stack.push(obj); |
aoqi@0 | 761 | _preserved_mark_stack.push(obj_mark); |
aoqi@0 | 762 | } |
aoqi@0 | 763 | } |
aoqi@0 | 764 | |
aoqi@0 | 765 | bool PSScavenge::should_attempt_scavenge() { |
aoqi@0 | 766 | ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); |
aoqi@0 | 767 | assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); |
aoqi@0 | 768 | PSGCAdaptivePolicyCounters* counters = heap->gc_policy_counters(); |
aoqi@0 | 769 | |
aoqi@0 | 770 | if (UsePerfData) { |
aoqi@0 | 771 | counters->update_scavenge_skipped(not_skipped); |
aoqi@0 | 772 | } |
aoqi@0 | 773 | |
aoqi@0 | 774 | PSYoungGen* young_gen = heap->young_gen(); |
aoqi@0 | 775 | PSOldGen* old_gen = heap->old_gen(); |
aoqi@0 | 776 | |
aoqi@0 | 777 | if (!ScavengeWithObjectsInToSpace) { |
aoqi@0 | 778 | // Do not attempt to promote unless to_space is empty |
aoqi@0 | 779 | if (!young_gen->to_space()->is_empty()) { |
aoqi@0 | 780 | _consecutive_skipped_scavenges++; |
aoqi@0 | 781 | if (UsePerfData) { |
aoqi@0 | 782 | counters->update_scavenge_skipped(to_space_not_empty); |
aoqi@0 | 783 | } |
aoqi@0 | 784 | return false; |
aoqi@0 | 785 | } |
aoqi@0 | 786 | } |
aoqi@0 | 787 | |
aoqi@0 | 788 | // Test to see if the scavenge will likely fail. |
aoqi@0 | 789 | PSAdaptiveSizePolicy* policy = heap->size_policy(); |
aoqi@0 | 790 | |
aoqi@0 | 791 | // A similar test is done in the policy's should_full_GC(). If this is |
aoqi@0 | 792 | // changed, decide if that test should also be changed. |
aoqi@0 | 793 | size_t avg_promoted = (size_t) policy->padded_average_promoted_in_bytes(); |
aoqi@0 | 794 | size_t promotion_estimate = MIN2(avg_promoted, young_gen->used_in_bytes()); |
aoqi@0 | 795 | bool result = promotion_estimate < old_gen->free_in_bytes(); |
aoqi@0 | 796 | |
aoqi@0 | 797 | if (PrintGCDetails && Verbose) { |
aoqi@0 | 798 | gclog_or_tty->print(result ? " do scavenge: " : " skip scavenge: "); |
aoqi@0 | 799 | gclog_or_tty->print_cr(" average_promoted " SIZE_FORMAT |
aoqi@0 | 800 | " padded_average_promoted " SIZE_FORMAT |
aoqi@0 | 801 | " free in old gen " SIZE_FORMAT, |
aoqi@0 | 802 | (size_t) policy->average_promoted_in_bytes(), |
aoqi@0 | 803 | (size_t) policy->padded_average_promoted_in_bytes(), |
aoqi@0 | 804 | old_gen->free_in_bytes()); |
aoqi@0 | 805 | if (young_gen->used_in_bytes() < |
aoqi@0 | 806 | (size_t) policy->padded_average_promoted_in_bytes()) { |
aoqi@0 | 807 | gclog_or_tty->print_cr(" padded_promoted_average is greater" |
aoqi@0 | 808 | " than maximum promotion = " SIZE_FORMAT, young_gen->used_in_bytes()); |
aoqi@0 | 809 | } |
aoqi@0 | 810 | } |
aoqi@0 | 811 | |
aoqi@0 | 812 | if (result) { |
aoqi@0 | 813 | _consecutive_skipped_scavenges = 0; |
aoqi@0 | 814 | } else { |
aoqi@0 | 815 | _consecutive_skipped_scavenges++; |
aoqi@0 | 816 | if (UsePerfData) { |
aoqi@0 | 817 | counters->update_scavenge_skipped(promoted_too_large); |
aoqi@0 | 818 | } |
aoqi@0 | 819 | } |
aoqi@0 | 820 | return result; |
aoqi@0 | 821 | } |
aoqi@0 | 822 | |
aoqi@0 | 823 | // Used to add tasks |
aoqi@0 | 824 | GCTaskManager* const PSScavenge::gc_task_manager() { |
aoqi@0 | 825 | assert(ParallelScavengeHeap::gc_task_manager() != NULL, |
aoqi@0 | 826 | "shouldn't return NULL"); |
aoqi@0 | 827 | return ParallelScavengeHeap::gc_task_manager(); |
aoqi@0 | 828 | } |
aoqi@0 | 829 | |
aoqi@0 | 830 | void PSScavenge::initialize() { |
aoqi@0 | 831 | // Arguments must have been parsed |
aoqi@0 | 832 | |
aoqi@0 | 833 | if (AlwaysTenure) { |
aoqi@0 | 834 | _tenuring_threshold = 0; |
aoqi@0 | 835 | } else if (NeverTenure) { |
aoqi@0 | 836 | _tenuring_threshold = markOopDesc::max_age + 1; |
aoqi@0 | 837 | } else { |
aoqi@0 | 838 | // We want to smooth out our startup times for the AdaptiveSizePolicy |
aoqi@0 | 839 | _tenuring_threshold = (UseAdaptiveSizePolicy) ? InitialTenuringThreshold : |
aoqi@0 | 840 | MaxTenuringThreshold; |
aoqi@0 | 841 | } |
aoqi@0 | 842 | |
aoqi@0 | 843 | ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); |
aoqi@0 | 844 | assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); |
aoqi@0 | 845 | |
aoqi@0 | 846 | PSYoungGen* young_gen = heap->young_gen(); |
aoqi@0 | 847 | PSOldGen* old_gen = heap->old_gen(); |
aoqi@0 | 848 | |
aoqi@0 | 849 | // Set boundary between young_gen and old_gen |
aoqi@0 | 850 | assert(old_gen->reserved().end() <= young_gen->eden_space()->bottom(), |
aoqi@0 | 851 | "old above young"); |
aoqi@0 | 852 | set_young_generation_boundary(young_gen->eden_space()->bottom()); |
aoqi@0 | 853 | |
aoqi@0 | 854 | // Initialize ref handling object for scavenging. |
aoqi@0 | 855 | MemRegion mr = young_gen->reserved(); |
aoqi@0 | 856 | |
aoqi@0 | 857 | _ref_processor = |
aoqi@0 | 858 | new ReferenceProcessor(mr, // span |
aoqi@0 | 859 | ParallelRefProcEnabled && (ParallelGCThreads > 1), // mt processing |
aoqi@0 | 860 | (int) ParallelGCThreads, // mt processing degree |
aoqi@0 | 861 | true, // mt discovery |
aoqi@0 | 862 | (int) ParallelGCThreads, // mt discovery degree |
aoqi@0 | 863 | true, // atomic_discovery |
aoqi@0 | 864 | NULL); // header provides liveness info |
aoqi@0 | 865 | |
aoqi@0 | 866 | // Cache the cardtable |
aoqi@0 | 867 | BarrierSet* bs = Universe::heap()->barrier_set(); |
aoqi@0 | 868 | assert(bs->kind() == BarrierSet::CardTableModRef, "Wrong barrier set kind"); |
aoqi@0 | 869 | _card_table = (CardTableExtension*)bs; |
aoqi@0 | 870 | |
aoqi@0 | 871 | _counters = new CollectorCounters("PSScavenge", 0); |
aoqi@0 | 872 | } |