1 /* 2 * Copyright (c) 2001, 2018, 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 "code/codeCache.hpp" 27 #include "gc/parallel/adjoiningGenerations.hpp" 28 #include "gc/parallel/adjoiningVirtualSpaces.hpp" 29 #include "gc/parallel/gcTaskManager.hpp" 30 #include "gc/parallel/generationSizer.hpp" 31 #include "gc/parallel/objectStartArray.inline.hpp" 32 #include "gc/parallel/parallelScavengeHeap.inline.hpp" 33 #include "gc/parallel/psAdaptiveSizePolicy.hpp" 34 #include "gc/parallel/psMarkSweep.hpp" 35 #include "gc/parallel/psMemoryPool.hpp" 36 #include "gc/parallel/psParallelCompact.inline.hpp" 37 #include "gc/parallel/psPromotionManager.hpp" 38 #include "gc/parallel/psScavenge.hpp" 39 #include "gc/parallel/vmPSOperations.hpp" 40 #include "gc/shared/gcHeapSummary.hpp" 41 #include "gc/shared/gcLocker.hpp" 42 #include "gc/shared/gcWhen.hpp" 43 #include "logging/log.hpp" 44 #include "memory/metaspaceCounters.hpp" 45 #include "oops/oop.inline.hpp" 46 #include "runtime/handles.inline.hpp" 47 #include "runtime/java.hpp" 48 #include "runtime/vmThread.hpp" 49 #include "services/memoryManager.hpp" 50 #include "services/memTracker.hpp" 51 #include "utilities/vmError.hpp" 52 53 PSYoungGen* ParallelScavengeHeap::_young_gen = NULL; 54 PSOldGen* ParallelScavengeHeap::_old_gen = NULL; 55 PSAdaptiveSizePolicy* ParallelScavengeHeap::_size_policy = NULL; 56 PSGCAdaptivePolicyCounters* ParallelScavengeHeap::_gc_policy_counters = NULL; 57 GCTaskManager* ParallelScavengeHeap::_gc_task_manager = NULL; 58 59 jint ParallelScavengeHeap::initialize() { 60 const size_t heap_size = _collector_policy->max_heap_byte_size(); 61 62 ReservedSpace heap_rs = Universe::reserve_heap(heap_size, _collector_policy->heap_alignment()); 63 64 os::trace_page_sizes("Heap", 65 _collector_policy->min_heap_byte_size(), 66 heap_size, 67 generation_alignment(), 68 heap_rs.base(), 69 heap_rs.size()); 70 71 initialize_reserved_region((HeapWord*)heap_rs.base(), (HeapWord*)(heap_rs.base() + heap_rs.size())); 72 73 PSCardTable* card_table = new PSCardTable(reserved_region()); 74 card_table->initialize(); 75 CardTableBarrierSet* const barrier_set = new CardTableBarrierSet(card_table); 76 barrier_set->initialize(); 77 BarrierSet::set_barrier_set(barrier_set); 78 79 // Make up the generations 80 // Calculate the maximum size that a generation can grow. This 81 // includes growth into the other generation. Note that the 82 // parameter _max_gen_size is kept as the maximum 83 // size of the generation as the boundaries currently stand. 84 // _max_gen_size is still used as that value. 85 double max_gc_pause_sec = ((double) MaxGCPauseMillis)/1000.0; 86 double max_gc_minor_pause_sec = ((double) MaxGCMinorPauseMillis)/1000.0; 87 88 _gens = new AdjoiningGenerations(heap_rs, _collector_policy, generation_alignment()); 89 90 _old_gen = _gens->old_gen(); 91 _young_gen = _gens->young_gen(); 92 93 const size_t eden_capacity = _young_gen->eden_space()->capacity_in_bytes(); 94 const size_t old_capacity = _old_gen->capacity_in_bytes(); 95 const size_t initial_promo_size = MIN2(eden_capacity, old_capacity); 96 _size_policy = 97 new PSAdaptiveSizePolicy(eden_capacity, 98 initial_promo_size, 99 young_gen()->to_space()->capacity_in_bytes(), 100 _collector_policy->gen_alignment(), 101 max_gc_pause_sec, 102 max_gc_minor_pause_sec, 103 GCTimeRatio 104 ); 105 106 assert(!UseAdaptiveGCBoundary || 107 (old_gen()->virtual_space()->high_boundary() == 108 young_gen()->virtual_space()->low_boundary()), 109 "Boundaries must meet"); 110 // initialize the policy counters - 2 collectors, 2 generations 111 _gc_policy_counters = 112 new PSGCAdaptivePolicyCounters("ParScav:MSC", 2, 2, _size_policy); 113 114 // Set up the GCTaskManager 115 _gc_task_manager = GCTaskManager::create(ParallelGCThreads); 116 117 if (UseParallelOldGC && !PSParallelCompact::initialize()) { 118 return JNI_ENOMEM; 119 } 120 121 return JNI_OK; 122 } 123 124 void ParallelScavengeHeap::initialize_serviceability() { 125 126 _eden_pool = new EdenMutableSpacePool(_young_gen, 127 _young_gen->eden_space(), 128 "PS Eden Space", 129 false /* support_usage_threshold */); 130 131 _survivor_pool = new SurvivorMutableSpacePool(_young_gen, 132 "PS Survivor Space", 133 false /* support_usage_threshold */); 134 135 _old_pool = new PSGenerationPool(_old_gen, 136 "PS Old Gen", 137 true /* support_usage_threshold */); 138 139 _young_manager = new GCMemoryManager("PS Scavenge", "end of minor GC"); 140 _old_manager = new GCMemoryManager("PS MarkSweep", "end of major GC"); 141 142 _old_manager->add_pool(_eden_pool); 143 _old_manager->add_pool(_survivor_pool); 144 _old_manager->add_pool(_old_pool); 145 146 _young_manager->add_pool(_eden_pool); 147 _young_manager->add_pool(_survivor_pool); 148 149 } 150 151 void ParallelScavengeHeap::post_initialize() { 152 CollectedHeap::post_initialize(); 153 // Need to init the tenuring threshold 154 PSScavenge::initialize(); 155 if (UseParallelOldGC) { 156 PSParallelCompact::post_initialize(); 157 } else { 158 PSMarkSweep::initialize(); 159 } 160 PSPromotionManager::initialize(); 161 } 162 163 void ParallelScavengeHeap::update_counters() { 164 young_gen()->update_counters(); 165 old_gen()->update_counters(); 166 MetaspaceCounters::update_performance_counters(); 167 CompressedClassSpaceCounters::update_performance_counters(); 168 } 169 170 size_t ParallelScavengeHeap::capacity() const { 171 size_t value = young_gen()->capacity_in_bytes() + old_gen()->capacity_in_bytes(); 172 return value; 173 } 174 175 size_t ParallelScavengeHeap::used() const { 176 size_t value = young_gen()->used_in_bytes() + old_gen()->used_in_bytes(); 177 return value; 178 } 179 180 bool ParallelScavengeHeap::is_maximal_no_gc() const { 181 return old_gen()->is_maximal_no_gc() && young_gen()->is_maximal_no_gc(); 182 } 183 184 185 size_t ParallelScavengeHeap::max_capacity() const { 186 size_t estimated = reserved_region().byte_size(); 187 if (UseAdaptiveSizePolicy) { 188 estimated -= _size_policy->max_survivor_size(young_gen()->max_size()); 189 } else { 190 estimated -= young_gen()->to_space()->capacity_in_bytes(); 191 } 192 return MAX2(estimated, capacity()); 193 } 194 195 bool ParallelScavengeHeap::is_in(const void* p) const { 196 return young_gen()->is_in(p) || old_gen()->is_in(p); 197 } 198 199 bool ParallelScavengeHeap::is_in_reserved(const void* p) const { 200 return young_gen()->is_in_reserved(p) || old_gen()->is_in_reserved(p); 201 } 202 203 // There are two levels of allocation policy here. 204 // 205 // When an allocation request fails, the requesting thread must invoke a VM 206 // operation, transfer control to the VM thread, and await the results of a 207 // garbage collection. That is quite expensive, and we should avoid doing it 208 // multiple times if possible. 209 // 210 // To accomplish this, we have a basic allocation policy, and also a 211 // failed allocation policy. 212 // 213 // The basic allocation policy controls how you allocate memory without 214 // attempting garbage collection. It is okay to grab locks and 215 // expand the heap, if that can be done without coming to a safepoint. 216 // It is likely that the basic allocation policy will not be very 217 // aggressive. 218 // 219 // The failed allocation policy is invoked from the VM thread after 220 // the basic allocation policy is unable to satisfy a mem_allocate 221 // request. This policy needs to cover the entire range of collection, 222 // heap expansion, and out-of-memory conditions. It should make every 223 // attempt to allocate the requested memory. 224 225 // Basic allocation policy. Should never be called at a safepoint, or 226 // from the VM thread. 227 // 228 // This method must handle cases where many mem_allocate requests fail 229 // simultaneously. When that happens, only one VM operation will succeed, 230 // and the rest will not be executed. For that reason, this method loops 231 // during failed allocation attempts. If the java heap becomes exhausted, 232 // we rely on the size_policy object to force a bail out. 233 HeapWord* ParallelScavengeHeap::mem_allocate( 234 size_t size, 235 bool* gc_overhead_limit_was_exceeded) { 236 assert(!SafepointSynchronize::is_at_safepoint(), "should not be at safepoint"); 237 assert(Thread::current() != (Thread*)VMThread::vm_thread(), "should not be in vm thread"); 238 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); 239 240 // In general gc_overhead_limit_was_exceeded should be false so 241 // set it so here and reset it to true only if the gc time 242 // limit is being exceeded as checked below. 243 *gc_overhead_limit_was_exceeded = false; 244 245 HeapWord* result = young_gen()->allocate(size); 246 247 uint loop_count = 0; 248 uint gc_count = 0; 249 uint gclocker_stalled_count = 0; 250 251 while (result == NULL) { 252 // We don't want to have multiple collections for a single filled generation. 253 // To prevent this, each thread tracks the total_collections() value, and if 254 // the count has changed, does not do a new collection. 255 // 256 // The collection count must be read only while holding the heap lock. VM 257 // operations also hold the heap lock during collections. There is a lock 258 // contention case where thread A blocks waiting on the Heap_lock, while 259 // thread B is holding it doing a collection. When thread A gets the lock, 260 // the collection count has already changed. To prevent duplicate collections, 261 // The policy MUST attempt allocations during the same period it reads the 262 // total_collections() value! 263 { 264 MutexLocker ml(Heap_lock); 265 gc_count = total_collections(); 266 267 result = young_gen()->allocate(size); 268 if (result != NULL) { 269 return result; 270 } 271 272 // If certain conditions hold, try allocating from the old gen. 273 result = mem_allocate_old_gen(size); 274 if (result != NULL) { 275 return result; 276 } 277 278 if (gclocker_stalled_count > GCLockerRetryAllocationCount) { 279 return NULL; 280 } 281 282 // Failed to allocate without a gc. 283 if (GCLocker::is_active_and_needs_gc()) { 284 // If this thread is not in a jni critical section, we stall 285 // the requestor until the critical section has cleared and 286 // GC allowed. When the critical section clears, a GC is 287 // initiated by the last thread exiting the critical section; so 288 // we retry the allocation sequence from the beginning of the loop, 289 // rather than causing more, now probably unnecessary, GC attempts. 290 JavaThread* jthr = JavaThread::current(); 291 if (!jthr->in_critical()) { 292 MutexUnlocker mul(Heap_lock); 293 GCLocker::stall_until_clear(); 294 gclocker_stalled_count += 1; 295 continue; 296 } else { 297 if (CheckJNICalls) { 298 fatal("Possible deadlock due to allocating while" 299 " in jni critical section"); 300 } 301 return NULL; 302 } 303 } 304 } 305 306 if (result == NULL) { 307 // Generate a VM operation 308 VM_ParallelGCFailedAllocation op(size, gc_count); 309 VMThread::execute(&op); 310 311 // Did the VM operation execute? If so, return the result directly. 312 // This prevents us from looping until time out on requests that can 313 // not be satisfied. 314 if (op.prologue_succeeded()) { 315 assert(is_in_or_null(op.result()), "result not in heap"); 316 317 // If GC was locked out during VM operation then retry allocation 318 // and/or stall as necessary. 319 if (op.gc_locked()) { 320 assert(op.result() == NULL, "must be NULL if gc_locked() is true"); 321 continue; // retry and/or stall as necessary 322 } 323 324 // Exit the loop if the gc time limit has been exceeded. 325 // The allocation must have failed above ("result" guarding 326 // this path is NULL) and the most recent collection has exceeded the 327 // gc overhead limit (although enough may have been collected to 328 // satisfy the allocation). Exit the loop so that an out-of-memory 329 // will be thrown (return a NULL ignoring the contents of 330 // op.result()), 331 // but clear gc_overhead_limit_exceeded so that the next collection 332 // starts with a clean slate (i.e., forgets about previous overhead 333 // excesses). Fill op.result() with a filler object so that the 334 // heap remains parsable. 335 const bool limit_exceeded = size_policy()->gc_overhead_limit_exceeded(); 336 const bool softrefs_clear = soft_ref_policy()->all_soft_refs_clear(); 337 338 if (limit_exceeded && softrefs_clear) { 339 *gc_overhead_limit_was_exceeded = true; 340 size_policy()->set_gc_overhead_limit_exceeded(false); 341 log_trace(gc)("ParallelScavengeHeap::mem_allocate: return NULL because gc_overhead_limit_exceeded is set"); 342 if (op.result() != NULL) { 343 CollectedHeap::fill_with_object(op.result(), size); 344 } 345 return NULL; 346 } 347 348 return op.result(); 349 } 350 } 351 352 // The policy object will prevent us from looping forever. If the 353 // time spent in gc crosses a threshold, we will bail out. 354 loop_count++; 355 if ((result == NULL) && (QueuedAllocationWarningCount > 0) && 356 (loop_count % QueuedAllocationWarningCount == 0)) { 357 log_warning(gc)("ParallelScavengeHeap::mem_allocate retries %d times", loop_count); 358 log_warning(gc)("\tsize=" SIZE_FORMAT, size); 359 } 360 } 361 362 return result; 363 } 364 365 // A "death march" is a series of ultra-slow allocations in which a full gc is 366 // done before each allocation, and after the full gc the allocation still 367 // cannot be satisfied from the young gen. This routine detects that condition; 368 // it should be called after a full gc has been done and the allocation 369 // attempted from the young gen. The parameter 'addr' should be the result of 370 // that young gen allocation attempt. 371 void 372 ParallelScavengeHeap::death_march_check(HeapWord* const addr, size_t size) { 373 if (addr != NULL) { 374 _death_march_count = 0; // death march has ended 375 } else if (_death_march_count == 0) { 376 if (should_alloc_in_eden(size)) { 377 _death_march_count = 1; // death march has started 378 } 379 } 380 } 381 382 HeapWord* ParallelScavengeHeap::mem_allocate_old_gen(size_t size) { 383 if (!should_alloc_in_eden(size) || GCLocker::is_active_and_needs_gc()) { 384 // Size is too big for eden, or gc is locked out. 385 return old_gen()->allocate(size); 386 } 387 388 // If a "death march" is in progress, allocate from the old gen a limited 389 // number of times before doing a GC. 390 if (_death_march_count > 0) { 391 if (_death_march_count < 64) { 392 ++_death_march_count; 393 return old_gen()->allocate(size); 394 } else { 395 _death_march_count = 0; 396 } 397 } 398 return NULL; 399 } 400 401 void ParallelScavengeHeap::do_full_collection(bool clear_all_soft_refs) { 402 if (UseParallelOldGC) { 403 // The do_full_collection() parameter clear_all_soft_refs 404 // is interpreted here as maximum_compaction which will 405 // cause SoftRefs to be cleared. 406 bool maximum_compaction = clear_all_soft_refs; 407 PSParallelCompact::invoke(maximum_compaction); 408 } else { 409 PSMarkSweep::invoke(clear_all_soft_refs); 410 } 411 } 412 413 // Failed allocation policy. Must be called from the VM thread, and 414 // only at a safepoint! Note that this method has policy for allocation 415 // flow, and NOT collection policy. So we do not check for gc collection 416 // time over limit here, that is the responsibility of the heap specific 417 // collection methods. This method decides where to attempt allocations, 418 // and when to attempt collections, but no collection specific policy. 419 HeapWord* ParallelScavengeHeap::failed_mem_allocate(size_t size) { 420 assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); 421 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); 422 assert(!is_gc_active(), "not reentrant"); 423 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); 424 425 // We assume that allocation in eden will fail unless we collect. 426 427 // First level allocation failure, scavenge and allocate in young gen. 428 GCCauseSetter gccs(this, GCCause::_allocation_failure); 429 const bool invoked_full_gc = PSScavenge::invoke(); 430 HeapWord* result = young_gen()->allocate(size); 431 432 // Second level allocation failure. 433 // Mark sweep and allocate in young generation. 434 if (result == NULL && !invoked_full_gc) { 435 do_full_collection(false); 436 result = young_gen()->allocate(size); 437 } 438 439 death_march_check(result, size); 440 441 // Third level allocation failure. 442 // After mark sweep and young generation allocation failure, 443 // allocate in old generation. 444 if (result == NULL) { 445 result = old_gen()->allocate(size); 446 } 447 448 // Fourth level allocation failure. We're running out of memory. 449 // More complete mark sweep and allocate in young generation. 450 if (result == NULL) { 451 do_full_collection(true); 452 result = young_gen()->allocate(size); 453 } 454 455 // Fifth level allocation failure. 456 // After more complete mark sweep, allocate in old generation. 457 if (result == NULL) { 458 result = old_gen()->allocate(size); 459 } 460 461 return result; 462 } 463 464 void ParallelScavengeHeap::ensure_parsability(bool retire_tlabs) { 465 CollectedHeap::ensure_parsability(retire_tlabs); 466 young_gen()->eden_space()->ensure_parsability(); 467 } 468 469 size_t ParallelScavengeHeap::tlab_capacity(Thread* thr) const { 470 return young_gen()->eden_space()->tlab_capacity(thr); 471 } 472 473 size_t ParallelScavengeHeap::tlab_used(Thread* thr) const { 474 return young_gen()->eden_space()->tlab_used(thr); 475 } 476 477 size_t ParallelScavengeHeap::unsafe_max_tlab_alloc(Thread* thr) const { 478 return young_gen()->eden_space()->unsafe_max_tlab_alloc(thr); 479 } 480 481 HeapWord* ParallelScavengeHeap::allocate_new_tlab(size_t minimal_size, size_t size, size_t* actual_size) { 482 *actual_size = size; 483 return young_gen()->allocate(size); 484 } 485 486 void ParallelScavengeHeap::accumulate_statistics_all_tlabs() { 487 CollectedHeap::accumulate_statistics_all_tlabs(); 488 } 489 490 void ParallelScavengeHeap::resize_all_tlabs() { 491 CollectedHeap::resize_all_tlabs(); 492 } 493 494 // This method is used by System.gc() and JVMTI. 495 void ParallelScavengeHeap::collect(GCCause::Cause cause) { 496 assert(!Heap_lock->owned_by_self(), 497 "this thread should not own the Heap_lock"); 498 499 uint gc_count = 0; 500 uint full_gc_count = 0; 501 { 502 MutexLocker ml(Heap_lock); 503 // This value is guarded by the Heap_lock 504 gc_count = total_collections(); 505 full_gc_count = total_full_collections(); 506 } 507 508 VM_ParallelGCSystemGC op(gc_count, full_gc_count, cause); 509 VMThread::execute(&op); 510 } 511 512 void ParallelScavengeHeap::object_iterate(ObjectClosure* cl) { 513 young_gen()->object_iterate(cl); 514 old_gen()->object_iterate(cl); 515 } 516 517 518 HeapWord* ParallelScavengeHeap::block_start(const void* addr) const { 519 if (young_gen()->is_in_reserved(addr)) { 520 assert(young_gen()->is_in(addr), 521 "addr should be in allocated part of young gen"); 522 // called from os::print_location by find or VMError 523 if (Debugging || VMError::fatal_error_in_progress()) return NULL; 524 Unimplemented(); 525 } else if (old_gen()->is_in_reserved(addr)) { 526 assert(old_gen()->is_in(addr), 527 "addr should be in allocated part of old gen"); 528 return old_gen()->start_array()->object_start((HeapWord*)addr); 529 } 530 return 0; 531 } 532 533 size_t ParallelScavengeHeap::block_size(const HeapWord* addr) const { 534 return oop(addr)->size(); 535 } 536 537 bool ParallelScavengeHeap::block_is_obj(const HeapWord* addr) const { 538 return block_start(addr) == addr; 539 } 540 541 jlong ParallelScavengeHeap::millis_since_last_gc() { 542 return UseParallelOldGC ? 543 PSParallelCompact::millis_since_last_gc() : 544 PSMarkSweep::millis_since_last_gc(); 545 } 546 547 void ParallelScavengeHeap::prepare_for_verify() { 548 ensure_parsability(false); // no need to retire TLABs for verification 549 } 550 551 PSHeapSummary ParallelScavengeHeap::create_ps_heap_summary() { 552 PSOldGen* old = old_gen(); 553 HeapWord* old_committed_end = (HeapWord*)old->virtual_space()->committed_high_addr(); 554 VirtualSpaceSummary old_summary(old->reserved().start(), old_committed_end, old->reserved().end()); 555 SpaceSummary old_space(old->reserved().start(), old_committed_end, old->used_in_bytes()); 556 557 PSYoungGen* young = young_gen(); 558 VirtualSpaceSummary young_summary(young->reserved().start(), 559 (HeapWord*)young->virtual_space()->committed_high_addr(), young->reserved().end()); 560 561 MutableSpace* eden = young_gen()->eden_space(); 562 SpaceSummary eden_space(eden->bottom(), eden->end(), eden->used_in_bytes()); 563 564 MutableSpace* from = young_gen()->from_space(); 565 SpaceSummary from_space(from->bottom(), from->end(), from->used_in_bytes()); 566 567 MutableSpace* to = young_gen()->to_space(); 568 SpaceSummary to_space(to->bottom(), to->end(), to->used_in_bytes()); 569 570 VirtualSpaceSummary heap_summary = create_heap_space_summary(); 571 return PSHeapSummary(heap_summary, used(), old_summary, old_space, young_summary, eden_space, from_space, to_space); 572 } 573 574 void ParallelScavengeHeap::print_on(outputStream* st) const { 575 young_gen()->print_on(st); 576 old_gen()->print_on(st); 577 MetaspaceUtils::print_on(st); 578 } 579 580 void ParallelScavengeHeap::print_on_error(outputStream* st) const { 581 this->CollectedHeap::print_on_error(st); 582 583 if (UseParallelOldGC) { 584 st->cr(); 585 PSParallelCompact::print_on_error(st); 586 } 587 } 588 589 void ParallelScavengeHeap::gc_threads_do(ThreadClosure* tc) const { 590 PSScavenge::gc_task_manager()->threads_do(tc); 591 } 592 593 void ParallelScavengeHeap::print_gc_threads_on(outputStream* st) const { 594 PSScavenge::gc_task_manager()->print_threads_on(st); 595 } 596 597 void ParallelScavengeHeap::print_tracing_info() const { 598 AdaptiveSizePolicyOutput::print(); 599 log_debug(gc, heap, exit)("Accumulated young generation GC time %3.7f secs", PSScavenge::accumulated_time()->seconds()); 600 log_debug(gc, heap, exit)("Accumulated old generation GC time %3.7f secs", 601 UseParallelOldGC ? PSParallelCompact::accumulated_time()->seconds() : PSMarkSweep::accumulated_time()->seconds()); 602 } 603 604 605 void ParallelScavengeHeap::verify(VerifyOption option /* ignored */) { 606 // Why do we need the total_collections()-filter below? 607 if (total_collections() > 0) { 608 log_debug(gc, verify)("Tenured"); 609 old_gen()->verify(); 610 611 log_debug(gc, verify)("Eden"); 612 young_gen()->verify(); 613 } 614 } 615 616 void ParallelScavengeHeap::trace_heap(GCWhen::Type when, const GCTracer* gc_tracer) { 617 const PSHeapSummary& heap_summary = create_ps_heap_summary(); 618 gc_tracer->report_gc_heap_summary(when, heap_summary); 619 620 const MetaspaceSummary& metaspace_summary = create_metaspace_summary(); 621 gc_tracer->report_metaspace_summary(when, metaspace_summary); 622 } 623 624 ParallelScavengeHeap* ParallelScavengeHeap::heap() { 625 CollectedHeap* heap = Universe::heap(); 626 assert(heap != NULL, "Uninitialized access to ParallelScavengeHeap::heap()"); 627 assert(heap->kind() == CollectedHeap::Parallel, "Invalid name"); 628 return (ParallelScavengeHeap*)heap; 629 } 630 631 CardTableBarrierSet* ParallelScavengeHeap::barrier_set() { 632 return barrier_set_cast<CardTableBarrierSet>(BarrierSet::barrier_set()); 633 } 634 635 PSCardTable* ParallelScavengeHeap::card_table() { 636 return static_cast<PSCardTable*>(barrier_set()->card_table()); 637 } 638 639 // Before delegating the resize to the young generation, 640 // the reserved space for the young and old generations 641 // may be changed to accommodate the desired resize. 642 void ParallelScavengeHeap::resize_young_gen(size_t eden_size, 643 size_t survivor_size) { 644 if (UseAdaptiveGCBoundary) { 645 if (size_policy()->bytes_absorbed_from_eden() != 0) { 646 size_policy()->reset_bytes_absorbed_from_eden(); 647 return; // The generation changed size already. 648 } 649 gens()->adjust_boundary_for_young_gen_needs(eden_size, survivor_size); 650 } 651 652 // Delegate the resize to the generation. 653 _young_gen->resize(eden_size, survivor_size); 654 } 655 656 // Before delegating the resize to the old generation, 657 // the reserved space for the young and old generations 658 // may be changed to accommodate the desired resize. 659 void ParallelScavengeHeap::resize_old_gen(size_t desired_free_space) { 660 if (UseAdaptiveGCBoundary) { 661 if (size_policy()->bytes_absorbed_from_eden() != 0) { 662 size_policy()->reset_bytes_absorbed_from_eden(); 663 return; // The generation changed size already. 664 } 665 gens()->adjust_boundary_for_old_gen_needs(desired_free_space); 666 } 667 668 // Delegate the resize to the generation. 669 _old_gen->resize(desired_free_space); 670 } 671 672 ParallelScavengeHeap::ParStrongRootsScope::ParStrongRootsScope() { 673 // nothing particular 674 } 675 676 ParallelScavengeHeap::ParStrongRootsScope::~ParStrongRootsScope() { 677 // nothing particular 678 } 679 680 #ifndef PRODUCT 681 void ParallelScavengeHeap::record_gen_tops_before_GC() { 682 if (ZapUnusedHeapArea) { 683 young_gen()->record_spaces_top(); 684 old_gen()->record_spaces_top(); 685 } 686 } 687 688 void ParallelScavengeHeap::gen_mangle_unused_area() { 689 if (ZapUnusedHeapArea) { 690 young_gen()->eden_space()->mangle_unused_area(); 691 young_gen()->to_space()->mangle_unused_area(); 692 young_gen()->from_space()->mangle_unused_area(); 693 old_gen()->object_space()->mangle_unused_area(); 694 } 695 } 696 #endif 697 698 bool ParallelScavengeHeap::is_scavengable(oop obj) { 699 return is_in_young(obj); 700 } 701 702 void ParallelScavengeHeap::register_nmethod(nmethod* nm) { 703 CodeCache::register_scavenge_root_nmethod(nm); 704 } 705 706 void ParallelScavengeHeap::verify_nmethod(nmethod* nm) { 707 CodeCache::verify_scavenge_root_nmethod(nm); 708 } 709 710 GrowableArray<GCMemoryManager*> ParallelScavengeHeap::memory_managers() { 711 GrowableArray<GCMemoryManager*> memory_managers(2); 712 memory_managers.append(_young_manager); 713 memory_managers.append(_old_manager); 714 return memory_managers; 715 } 716 717 GrowableArray<MemoryPool*> ParallelScavengeHeap::memory_pools() { 718 GrowableArray<MemoryPool*> memory_pools(3); 719 memory_pools.append(_eden_pool); 720 memory_pools.append(_survivor_pool); 721 memory_pools.append(_old_pool); 722 return memory_pools; 723 }