1 /* 2 * Copyright (c) 2001, 2025, 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 "gc/parallel/objectStartArray.inline.hpp" 26 #include "gc/parallel/parallelArguments.hpp" 27 #include "gc/parallel/parallelInitLogger.hpp" 28 #include "gc/parallel/parallelScavengeHeap.inline.hpp" 29 #include "gc/parallel/psAdaptiveSizePolicy.hpp" 30 #include "gc/parallel/psMemoryPool.hpp" 31 #include "gc/parallel/psParallelCompact.inline.hpp" 32 #include "gc/parallel/psParallelCompactNew.inline.hpp" 33 #include "gc/parallel/psPromotionManager.hpp" 34 #include "gc/parallel/psScavenge.hpp" 35 #include "gc/parallel/psVMOperations.hpp" 36 #include "gc/shared/fullGCForwarding.inline.hpp" 37 #include "gc/shared/gcHeapSummary.hpp" 38 #include "gc/shared/gcLocker.inline.hpp" 39 #include "gc/shared/gcWhen.hpp" 40 #include "gc/shared/genArguments.hpp" 41 #include "gc/shared/locationPrinter.inline.hpp" 42 #include "gc/shared/scavengableNMethods.hpp" 43 #include "gc/shared/suspendibleThreadSet.hpp" 44 #include "logging/log.hpp" 45 #include "memory/iterator.hpp" 46 #include "memory/metaspaceCounters.hpp" 47 #include "memory/metaspaceUtils.hpp" 48 #include "memory/reservedSpace.hpp" 49 #include "memory/universe.hpp" 50 #include "oops/oop.inline.hpp" 51 #include "runtime/cpuTimeCounters.hpp" 52 #include "runtime/handles.inline.hpp" 53 #include "runtime/java.hpp" 54 #include "runtime/vmThread.hpp" 55 #include "services/memoryManager.hpp" 56 #include "utilities/macros.hpp" 57 #include "utilities/vmError.hpp" 58 59 PSYoungGen* ParallelScavengeHeap::_young_gen = nullptr; 60 PSOldGen* ParallelScavengeHeap::_old_gen = nullptr; 61 PSAdaptiveSizePolicy* ParallelScavengeHeap::_size_policy = nullptr; 62 PSGCAdaptivePolicyCounters* ParallelScavengeHeap::_gc_policy_counters = nullptr; 63 64 jint ParallelScavengeHeap::initialize() { 65 const size_t reserved_heap_size = ParallelArguments::heap_reserved_size_bytes(); 66 67 ReservedHeapSpace heap_rs = Universe::reserve_heap(reserved_heap_size, HeapAlignment); 68 69 trace_actual_reserved_page_size(reserved_heap_size, heap_rs); 70 71 initialize_reserved_region(heap_rs); 72 // Layout the reserved space for the generations. 73 ReservedSpace old_rs = heap_rs.first_part(MaxOldSize, SpaceAlignment); 74 ReservedSpace young_rs = heap_rs.last_part(MaxOldSize, SpaceAlignment); 75 assert(young_rs.size() == MaxNewSize, "Didn't reserve all of the heap"); 76 77 PSCardTable* card_table = new PSCardTable(_reserved); 78 card_table->initialize(old_rs.base(), young_rs.base()); 79 80 CardTableBarrierSet* const barrier_set = new CardTableBarrierSet(card_table); 81 barrier_set->initialize(); 82 BarrierSet::set_barrier_set(barrier_set); 83 84 // Set up WorkerThreads 85 _workers.initialize_workers(); 86 87 // Create and initialize the generations. 88 _young_gen = new PSYoungGen( 89 young_rs, 90 NewSize, 91 MinNewSize, 92 MaxNewSize); 93 _old_gen = new PSOldGen( 94 old_rs, 95 OldSize, 96 MinOldSize, 97 MaxOldSize); 98 99 assert(young_gen()->max_gen_size() == young_rs.size(),"Consistency check"); 100 assert(old_gen()->max_gen_size() == old_rs.size(), "Consistency check"); 101 102 double max_gc_pause_sec = ((double) MaxGCPauseMillis)/1000.0; 103 104 const size_t eden_capacity = _young_gen->eden_space()->capacity_in_bytes(); 105 const size_t old_capacity = _old_gen->capacity_in_bytes(); 106 const size_t initial_promo_size = MIN2(eden_capacity, old_capacity); 107 _size_policy = 108 new PSAdaptiveSizePolicy(eden_capacity, 109 initial_promo_size, 110 young_gen()->to_space()->capacity_in_bytes(), 111 SpaceAlignment, 112 max_gc_pause_sec, 113 GCTimeRatio 114 ); 115 116 assert((old_gen()->virtual_space()->high_boundary() == 117 young_gen()->virtual_space()->low_boundary()), 118 "Boundaries must meet"); 119 // initialize the policy counters - 2 collectors, 2 generations 120 _gc_policy_counters = 121 new PSGCAdaptivePolicyCounters("ParScav:MSC", 2, 2, _size_policy); 122 123 if (UseCompactObjectHeaders) { 124 if (!PSParallelCompactNew::initialize_aux_data()) { 125 return JNI_ENOMEM; 126 } 127 } else { 128 if (!PSParallelCompact::initialize_aux_data()) { 129 return JNI_ENOMEM; 130 } 131 } 132 133 // Create CPU time counter 134 CPUTimeCounters::create_counter(CPUTimeGroups::CPUTimeType::gc_parallel_workers); 135 136 ParallelInitLogger::print(); 137 138 FullGCForwarding::initialize(_reserved); 139 140 return JNI_OK; 141 } 142 143 void ParallelScavengeHeap::initialize_serviceability() { 144 145 _eden_pool = new EdenMutableSpacePool(_young_gen, 146 _young_gen->eden_space(), 147 "PS Eden Space", 148 false /* support_usage_threshold */); 149 150 _survivor_pool = new SurvivorMutableSpacePool(_young_gen, 151 "PS Survivor Space", 152 false /* support_usage_threshold */); 153 154 _old_pool = new PSGenerationPool(_old_gen, 155 "PS Old Gen", 156 true /* support_usage_threshold */); 157 158 _young_manager = new GCMemoryManager("PS Scavenge"); 159 _old_manager = new GCMemoryManager("PS MarkSweep"); 160 161 _old_manager->add_pool(_eden_pool); 162 _old_manager->add_pool(_survivor_pool); 163 _old_manager->add_pool(_old_pool); 164 165 _young_manager->add_pool(_eden_pool); 166 _young_manager->add_pool(_survivor_pool); 167 168 } 169 170 void ParallelScavengeHeap::safepoint_synchronize_begin() { 171 if (UseStringDeduplication) { 172 SuspendibleThreadSet::synchronize(); 173 } 174 } 175 176 void ParallelScavengeHeap::safepoint_synchronize_end() { 177 if (UseStringDeduplication) { 178 SuspendibleThreadSet::desynchronize(); 179 } 180 } 181 class PSIsScavengable : public BoolObjectClosure { 182 bool do_object_b(oop obj) { 183 return ParallelScavengeHeap::heap()->is_in_young(obj); 184 } 185 }; 186 187 static PSIsScavengable _is_scavengable; 188 189 void ParallelScavengeHeap::post_initialize() { 190 CollectedHeap::post_initialize(); 191 // Need to init the tenuring threshold 192 PSScavenge::initialize(); 193 if (UseCompactObjectHeaders) { 194 PSParallelCompactNew::post_initialize(); 195 } else { 196 PSParallelCompact::post_initialize(); 197 } 198 PSPromotionManager::initialize(); 199 200 ScavengableNMethods::initialize(&_is_scavengable); 201 GCLocker::initialize(); 202 } 203 204 void ParallelScavengeHeap::update_counters() { 205 young_gen()->update_counters(); 206 old_gen()->update_counters(); 207 MetaspaceCounters::update_performance_counters(); 208 update_parallel_worker_threads_cpu_time(); 209 } 210 211 size_t ParallelScavengeHeap::capacity() const { 212 size_t value = young_gen()->capacity_in_bytes() + old_gen()->capacity_in_bytes(); 213 return value; 214 } 215 216 size_t ParallelScavengeHeap::used() const { 217 size_t value = young_gen()->used_in_bytes() + old_gen()->used_in_bytes(); 218 return value; 219 } 220 221 size_t ParallelScavengeHeap::max_capacity() const { 222 size_t estimated = reserved_region().byte_size(); 223 if (UseAdaptiveSizePolicy) { 224 estimated -= _size_policy->max_survivor_size(young_gen()->max_gen_size()); 225 } else { 226 estimated -= young_gen()->to_space()->capacity_in_bytes(); 227 } 228 return MAX2(estimated, capacity()); 229 } 230 231 bool ParallelScavengeHeap::is_in(const void* p) const { 232 return young_gen()->is_in(p) || old_gen()->is_in(p); 233 } 234 235 bool ParallelScavengeHeap::is_in_reserved(const void* p) const { 236 return young_gen()->is_in_reserved(p) || old_gen()->is_in_reserved(p); 237 } 238 239 bool ParallelScavengeHeap::requires_barriers(stackChunkOop p) const { 240 return !is_in_young(p); 241 } 242 243 // There are two levels of allocation policy here. 244 // 245 // When an allocation request fails, the requesting thread must invoke a VM 246 // operation, transfer control to the VM thread, and await the results of a 247 // garbage collection. That is quite expensive, and we should avoid doing it 248 // multiple times if possible. 249 // 250 // To accomplish this, we have a basic allocation policy, and also a 251 // failed allocation policy. 252 // 253 // The basic allocation policy controls how you allocate memory without 254 // attempting garbage collection. It is okay to grab locks and 255 // expand the heap, if that can be done without coming to a safepoint. 256 // It is likely that the basic allocation policy will not be very 257 // aggressive. 258 // 259 // The failed allocation policy is invoked from the VM thread after 260 // the basic allocation policy is unable to satisfy a mem_allocate 261 // request. This policy needs to cover the entire range of collection, 262 // heap expansion, and out-of-memory conditions. It should make every 263 // attempt to allocate the requested memory. 264 265 // Basic allocation policy. Should never be called at a safepoint, or 266 // from the VM thread. 267 // 268 // This method must handle cases where many mem_allocate requests fail 269 // simultaneously. When that happens, only one VM operation will succeed, 270 // and the rest will not be executed. For that reason, this method loops 271 // during failed allocation attempts. If the java heap becomes exhausted, 272 // we rely on the size_policy object to force a bail out. 273 HeapWord* ParallelScavengeHeap::mem_allocate(size_t size, 274 bool* gc_overhead_limit_was_exceeded) { 275 assert(!SafepointSynchronize::is_at_safepoint(), "should not be at safepoint"); 276 assert(Thread::current() != (Thread*)VMThread::vm_thread(), "should not be in vm thread"); 277 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); 278 279 bool is_tlab = false; 280 return mem_allocate_work(size, is_tlab, gc_overhead_limit_was_exceeded); 281 } 282 283 HeapWord* ParallelScavengeHeap::mem_allocate_work(size_t size, 284 bool is_tlab, 285 bool* gc_overhead_limit_was_exceeded) { 286 287 // In general gc_overhead_limit_was_exceeded should be false so 288 // set it so here and reset it to true only if the gc time 289 // limit is being exceeded as checked below. 290 *gc_overhead_limit_was_exceeded = false; 291 292 HeapWord* result = young_gen()->allocate(size); 293 294 uint loop_count = 0; 295 uint gc_count = 0; 296 297 while (result == nullptr) { 298 // We don't want to have multiple collections for a single filled generation. 299 // To prevent this, each thread tracks the total_collections() value, and if 300 // the count has changed, does not do a new collection. 301 // 302 // The collection count must be read only while holding the heap lock. VM 303 // operations also hold the heap lock during collections. There is a lock 304 // contention case where thread A blocks waiting on the Heap_lock, while 305 // thread B is holding it doing a collection. When thread A gets the lock, 306 // the collection count has already changed. To prevent duplicate collections, 307 // The policy MUST attempt allocations during the same period it reads the 308 // total_collections() value! 309 { 310 MutexLocker ml(Heap_lock); 311 gc_count = total_collections(); 312 313 result = young_gen()->allocate(size); 314 if (result != nullptr) { 315 return result; 316 } 317 318 // If certain conditions hold, try allocating from the old gen. 319 if (!is_tlab) { 320 result = mem_allocate_old_gen(size); 321 if (result != nullptr) { 322 return result; 323 } 324 } 325 } 326 327 assert(result == nullptr, "inv"); 328 { 329 VM_ParallelCollectForAllocation op(size, is_tlab, gc_count); 330 VMThread::execute(&op); 331 332 // Did the VM operation execute? If so, return the result directly. 333 // This prevents us from looping until time out on requests that can 334 // not be satisfied. 335 if (op.gc_succeeded()) { 336 assert(is_in_or_null(op.result()), "result not in heap"); 337 338 // Exit the loop if the gc time limit has been exceeded. 339 // The allocation must have failed above ("result" guarding 340 // this path is null) and the most recent collection has exceeded the 341 // gc overhead limit (although enough may have been collected to 342 // satisfy the allocation). Exit the loop so that an out-of-memory 343 // will be thrown (return a null ignoring the contents of 344 // op.result()), 345 // but clear gc_overhead_limit_exceeded so that the next collection 346 // starts with a clean slate (i.e., forgets about previous overhead 347 // excesses). Fill op.result() with a filler object so that the 348 // heap remains parsable. 349 const bool limit_exceeded = size_policy()->gc_overhead_limit_exceeded(); 350 const bool softrefs_clear = soft_ref_policy()->all_soft_refs_clear(); 351 352 if (limit_exceeded && softrefs_clear) { 353 *gc_overhead_limit_was_exceeded = true; 354 size_policy()->set_gc_overhead_limit_exceeded(false); 355 log_trace(gc)("ParallelScavengeHeap::mem_allocate: return null because gc_overhead_limit_exceeded is set"); 356 if (op.result() != nullptr) { 357 CollectedHeap::fill_with_object(op.result(), size); 358 } 359 return nullptr; 360 } 361 362 return op.result(); 363 } 364 } 365 366 // The policy object will prevent us from looping forever. If the 367 // time spent in gc crosses a threshold, we will bail out. 368 loop_count++; 369 if ((result == nullptr) && (QueuedAllocationWarningCount > 0) && 370 (loop_count % QueuedAllocationWarningCount == 0)) { 371 log_warning(gc)("ParallelScavengeHeap::mem_allocate retries %d times", loop_count); 372 log_warning(gc)("\tsize=%zu", size); 373 } 374 } 375 376 return result; 377 } 378 379 HeapWord* ParallelScavengeHeap::allocate_old_gen_and_record(size_t size) { 380 assert_locked_or_safepoint(Heap_lock); 381 HeapWord* res = old_gen()->allocate(size); 382 if (res != nullptr) { 383 _size_policy->tenured_allocation(size * HeapWordSize); 384 } 385 return res; 386 } 387 388 HeapWord* ParallelScavengeHeap::mem_allocate_old_gen(size_t size) { 389 if (!should_alloc_in_eden(size)) { 390 // Size is too big for eden. 391 return allocate_old_gen_and_record(size); 392 } 393 394 return nullptr; 395 } 396 397 void ParallelScavengeHeap::do_full_collection(bool clear_all_soft_refs) { 398 if (UseCompactObjectHeaders) { 399 PSParallelCompactNew::invoke(clear_all_soft_refs, false /* serial */); 400 } else { 401 PSParallelCompact::invoke(clear_all_soft_refs); 402 } 403 } 404 405 HeapWord* ParallelScavengeHeap::expand_heap_and_allocate(size_t size, bool is_tlab) { 406 HeapWord* result = nullptr; 407 408 result = young_gen()->allocate(size); 409 if (result == nullptr && !is_tlab) { 410 result = old_gen()->expand_and_allocate(size); 411 } 412 return result; // Could be null if we are out of space. 413 } 414 415 HeapWord* ParallelScavengeHeap::satisfy_failed_allocation(size_t size, bool is_tlab) { 416 assert(size != 0, "precondition"); 417 418 HeapWord* result = nullptr; 419 420 // If young-gen can handle this allocation, attempt young-gc firstly. 421 bool should_run_young_gc = is_tlab || should_alloc_in_eden(size); 422 collect_at_safepoint(!should_run_young_gc); 423 424 result = expand_heap_and_allocate(size, is_tlab); 425 if (result != nullptr) { 426 return result; 427 } 428 429 // If we reach this point, we're really out of memory. Try every trick 430 // we can to reclaim memory. Force collection of soft references. Force 431 // a complete compaction of the heap. Any additional methods for finding 432 // free memory should be here, especially if they are expensive. If this 433 // attempt fails, an OOM exception will be thrown. 434 { 435 // Make sure the heap is fully compacted 436 uintx old_interval = HeapMaximumCompactionInterval; 437 HeapMaximumCompactionInterval = 0; 438 439 const bool clear_all_soft_refs = true; 440 if (UseCompactObjectHeaders) { 441 PSParallelCompactNew::invoke(clear_all_soft_refs, false /* serial */); 442 } else { 443 PSParallelCompact::invoke(clear_all_soft_refs); 444 } 445 446 // Restore 447 HeapMaximumCompactionInterval = old_interval; 448 } 449 450 result = expand_heap_and_allocate(size, is_tlab); 451 if (result != nullptr) { 452 return result; 453 } 454 455 if (UseCompactObjectHeaders) { 456 PSParallelCompactNew::invoke(true /* clear_soft_refs */, true /* serial */); 457 } 458 459 result = expand_heap_and_allocate(size, is_tlab); 460 if (result != nullptr) { 461 return result; 462 } 463 464 // What else? We might try synchronous finalization later. If the total 465 // space available is large enough for the allocation, then a more 466 // complete compaction phase than we've tried so far might be 467 // appropriate. 468 return nullptr; 469 } 470 471 472 void ParallelScavengeHeap::ensure_parsability(bool retire_tlabs) { 473 CollectedHeap::ensure_parsability(retire_tlabs); 474 young_gen()->eden_space()->ensure_parsability(); 475 } 476 477 size_t ParallelScavengeHeap::tlab_capacity(Thread* thr) const { 478 return young_gen()->eden_space()->tlab_capacity(thr); 479 } 480 481 size_t ParallelScavengeHeap::tlab_used(Thread* thr) const { 482 return young_gen()->eden_space()->tlab_used(thr); 483 } 484 485 size_t ParallelScavengeHeap::unsafe_max_tlab_alloc(Thread* thr) const { 486 return young_gen()->eden_space()->unsafe_max_tlab_alloc(thr); 487 } 488 489 HeapWord* ParallelScavengeHeap::allocate_new_tlab(size_t min_size, size_t requested_size, size_t* actual_size) { 490 bool dummy; 491 HeapWord* result = mem_allocate_work(requested_size /* size */, 492 true /* is_tlab */, 493 &dummy); 494 if (result != nullptr) { 495 *actual_size = requested_size; 496 } 497 498 return result; 499 } 500 501 void ParallelScavengeHeap::resize_all_tlabs() { 502 CollectedHeap::resize_all_tlabs(); 503 } 504 505 void ParallelScavengeHeap::prune_scavengable_nmethods() { 506 ScavengableNMethods::prune_nmethods_not_into_young(); 507 } 508 509 void ParallelScavengeHeap::prune_unlinked_nmethods() { 510 ScavengableNMethods::prune_unlinked_nmethods(); 511 } 512 513 void ParallelScavengeHeap::collect(GCCause::Cause cause) { 514 assert(!Heap_lock->owned_by_self(), 515 "this thread should not own the Heap_lock"); 516 517 uint gc_count = 0; 518 uint full_gc_count = 0; 519 { 520 MutexLocker ml(Heap_lock); 521 // This value is guarded by the Heap_lock 522 gc_count = total_collections(); 523 full_gc_count = total_full_collections(); 524 } 525 526 VM_ParallelGCCollect op(gc_count, full_gc_count, cause); 527 VMThread::execute(&op); 528 } 529 530 bool ParallelScavengeHeap::must_clear_all_soft_refs() { 531 return _gc_cause == GCCause::_metadata_GC_clear_soft_refs || 532 _gc_cause == GCCause::_wb_full_gc; 533 } 534 535 void ParallelScavengeHeap::collect_at_safepoint(bool full) { 536 assert(!GCLocker::is_active(), "precondition"); 537 bool clear_soft_refs = must_clear_all_soft_refs(); 538 539 if (!full) { 540 bool success = PSScavenge::invoke(clear_soft_refs); 541 if (success) { 542 return; 543 } 544 // Upgrade to Full-GC if young-gc fails 545 } 546 if (UseCompactObjectHeaders) { 547 PSParallelCompactNew::invoke(clear_soft_refs, false /* serial */); 548 } else { 549 PSParallelCompact::invoke(clear_soft_refs); 550 } 551 } 552 553 void ParallelScavengeHeap::object_iterate(ObjectClosure* cl) { 554 young_gen()->object_iterate(cl); 555 old_gen()->object_iterate(cl); 556 } 557 558 // The HeapBlockClaimer is used during parallel iteration over the heap, 559 // allowing workers to claim heap areas ("blocks"), gaining exclusive rights to these. 560 // The eden and survivor spaces are treated as single blocks as it is hard to divide 561 // these spaces. 562 // The old space is divided into fixed-size blocks. 563 class HeapBlockClaimer : public StackObj { 564 size_t _claimed_index; 565 566 public: 567 static const size_t InvalidIndex = SIZE_MAX; 568 static const size_t EdenIndex = 0; 569 static const size_t SurvivorIndex = 1; 570 static const size_t NumNonOldGenClaims = 2; 571 572 HeapBlockClaimer() : _claimed_index(EdenIndex) { } 573 // Claim the block and get the block index. 574 size_t claim_and_get_block() { 575 size_t block_index; 576 block_index = Atomic::fetch_then_add(&_claimed_index, 1u); 577 578 PSOldGen* old_gen = ParallelScavengeHeap::heap()->old_gen(); 579 size_t num_claims = old_gen->num_iterable_blocks() + NumNonOldGenClaims; 580 581 return block_index < num_claims ? block_index : InvalidIndex; 582 } 583 }; 584 585 void ParallelScavengeHeap::object_iterate_parallel(ObjectClosure* cl, 586 HeapBlockClaimer* claimer) { 587 size_t block_index = claimer->claim_and_get_block(); 588 // Iterate until all blocks are claimed 589 if (block_index == HeapBlockClaimer::EdenIndex) { 590 young_gen()->eden_space()->object_iterate(cl); 591 block_index = claimer->claim_and_get_block(); 592 } 593 if (block_index == HeapBlockClaimer::SurvivorIndex) { 594 young_gen()->from_space()->object_iterate(cl); 595 young_gen()->to_space()->object_iterate(cl); 596 block_index = claimer->claim_and_get_block(); 597 } 598 while (block_index != HeapBlockClaimer::InvalidIndex) { 599 old_gen()->object_iterate_block(cl, block_index - HeapBlockClaimer::NumNonOldGenClaims); 600 block_index = claimer->claim_and_get_block(); 601 } 602 } 603 604 class PSScavengeParallelObjectIterator : public ParallelObjectIteratorImpl { 605 private: 606 ParallelScavengeHeap* _heap; 607 HeapBlockClaimer _claimer; 608 609 public: 610 PSScavengeParallelObjectIterator() : 611 _heap(ParallelScavengeHeap::heap()), 612 _claimer() {} 613 614 virtual void object_iterate(ObjectClosure* cl, uint worker_id) { 615 _heap->object_iterate_parallel(cl, &_claimer); 616 } 617 }; 618 619 ParallelObjectIteratorImpl* ParallelScavengeHeap::parallel_object_iterator(uint thread_num) { 620 return new PSScavengeParallelObjectIterator(); 621 } 622 623 HeapWord* ParallelScavengeHeap::block_start(const void* addr) const { 624 if (young_gen()->is_in_reserved(addr)) { 625 assert(young_gen()->is_in(addr), 626 "addr should be in allocated part of young gen"); 627 // called from os::print_location by find or VMError 628 if (DebuggingContext::is_enabled() || VMError::is_error_reported()) { 629 return nullptr; 630 } 631 Unimplemented(); 632 } else if (old_gen()->is_in_reserved(addr)) { 633 assert(old_gen()->is_in(addr), 634 "addr should be in allocated part of old gen"); 635 return old_gen()->start_array()->object_start((HeapWord*)addr); 636 } 637 return nullptr; 638 } 639 640 bool ParallelScavengeHeap::block_is_obj(const HeapWord* addr) const { 641 return block_start(addr) == addr; 642 } 643 644 void ParallelScavengeHeap::prepare_for_verify() { 645 ensure_parsability(false); // no need to retire TLABs for verification 646 } 647 648 PSHeapSummary ParallelScavengeHeap::create_ps_heap_summary() { 649 PSOldGen* old = old_gen(); 650 HeapWord* old_committed_end = (HeapWord*)old->virtual_space()->committed_high_addr(); 651 HeapWord* old_reserved_start = old->reserved().start(); 652 HeapWord* old_reserved_end = old->reserved().end(); 653 VirtualSpaceSummary old_summary(old_reserved_start, old_committed_end, old_reserved_end); 654 SpaceSummary old_space(old_reserved_start, old_committed_end, old->used_in_bytes()); 655 656 PSYoungGen* young = young_gen(); 657 VirtualSpaceSummary young_summary(young->reserved().start(), 658 (HeapWord*)young->virtual_space()->committed_high_addr(), young->reserved().end()); 659 660 MutableSpace* eden = young_gen()->eden_space(); 661 SpaceSummary eden_space(eden->bottom(), eden->end(), eden->used_in_bytes()); 662 663 MutableSpace* from = young_gen()->from_space(); 664 SpaceSummary from_space(from->bottom(), from->end(), from->used_in_bytes()); 665 666 MutableSpace* to = young_gen()->to_space(); 667 SpaceSummary to_space(to->bottom(), to->end(), to->used_in_bytes()); 668 669 VirtualSpaceSummary heap_summary = create_heap_space_summary(); 670 return PSHeapSummary(heap_summary, used(), old_summary, old_space, young_summary, eden_space, from_space, to_space); 671 } 672 673 bool ParallelScavengeHeap::print_location(outputStream* st, void* addr) const { 674 return BlockLocationPrinter<ParallelScavengeHeap>::print_location(st, addr); 675 } 676 677 void ParallelScavengeHeap::print_heap_on(outputStream* st) const { 678 if (young_gen() != nullptr) { 679 young_gen()->print_on(st); 680 } 681 if (old_gen() != nullptr) { 682 old_gen()->print_on(st); 683 } 684 } 685 686 void ParallelScavengeHeap::print_gc_on(outputStream* st) const { 687 BarrierSet* bs = BarrierSet::barrier_set(); 688 if (bs != nullptr) { 689 bs->print_on(st); 690 } 691 st->cr(); 692 693 if (UseCompactObjectHeaders) { 694 PSParallelCompactNew::print_on(st); 695 } else { 696 PSParallelCompact::print_on(st); 697 } 698 } 699 700 void ParallelScavengeHeap::gc_threads_do(ThreadClosure* tc) const { 701 ParallelScavengeHeap::heap()->workers().threads_do(tc); 702 } 703 704 void ParallelScavengeHeap::print_tracing_info() const { 705 AdaptiveSizePolicyOutput::print(); 706 log_debug(gc, heap, exit)("Accumulated young generation GC time %3.7f secs", PSScavenge::accumulated_time()->seconds()); 707 if (UseCompactObjectHeaders) { 708 log_debug(gc, heap, exit)("Accumulated old generation GC time %3.7f secs", PSParallelCompactNew::accumulated_time()->seconds()); 709 } else { 710 log_debug(gc, heap, exit)("Accumulated old generation GC time %3.7f secs", PSParallelCompact::accumulated_time()->seconds()); 711 } 712 } 713 714 PreGenGCValues ParallelScavengeHeap::get_pre_gc_values() const { 715 const PSYoungGen* const young = young_gen(); 716 const MutableSpace* const eden = young->eden_space(); 717 const MutableSpace* const from = young->from_space(); 718 const PSOldGen* const old = old_gen(); 719 720 return PreGenGCValues(young->used_in_bytes(), 721 young->capacity_in_bytes(), 722 eden->used_in_bytes(), 723 eden->capacity_in_bytes(), 724 from->used_in_bytes(), 725 from->capacity_in_bytes(), 726 old->used_in_bytes(), 727 old->capacity_in_bytes()); 728 } 729 730 void ParallelScavengeHeap::print_heap_change(const PreGenGCValues& pre_gc_values) const { 731 const PSYoungGen* const young = young_gen(); 732 const MutableSpace* const eden = young->eden_space(); 733 const MutableSpace* const from = young->from_space(); 734 const PSOldGen* const old = old_gen(); 735 736 log_info(gc, heap)(HEAP_CHANGE_FORMAT" " 737 HEAP_CHANGE_FORMAT" " 738 HEAP_CHANGE_FORMAT, 739 HEAP_CHANGE_FORMAT_ARGS(young->name(), 740 pre_gc_values.young_gen_used(), 741 pre_gc_values.young_gen_capacity(), 742 young->used_in_bytes(), 743 young->capacity_in_bytes()), 744 HEAP_CHANGE_FORMAT_ARGS("Eden", 745 pre_gc_values.eden_used(), 746 pre_gc_values.eden_capacity(), 747 eden->used_in_bytes(), 748 eden->capacity_in_bytes()), 749 HEAP_CHANGE_FORMAT_ARGS("From", 750 pre_gc_values.from_used(), 751 pre_gc_values.from_capacity(), 752 from->used_in_bytes(), 753 from->capacity_in_bytes())); 754 log_info(gc, heap)(HEAP_CHANGE_FORMAT, 755 HEAP_CHANGE_FORMAT_ARGS(old->name(), 756 pre_gc_values.old_gen_used(), 757 pre_gc_values.old_gen_capacity(), 758 old->used_in_bytes(), 759 old->capacity_in_bytes())); 760 MetaspaceUtils::print_metaspace_change(pre_gc_values.metaspace_sizes()); 761 } 762 763 void ParallelScavengeHeap::verify(VerifyOption option /* ignored */) { 764 // Why do we need the total_collections()-filter below? 765 if (total_collections() > 0) { 766 log_debug(gc, verify)("Tenured"); 767 old_gen()->verify(); 768 769 log_debug(gc, verify)("Eden"); 770 young_gen()->verify(); 771 772 log_debug(gc, verify)("CardTable"); 773 card_table()->verify_all_young_refs_imprecise(); 774 } 775 } 776 777 void ParallelScavengeHeap::trace_actual_reserved_page_size(const size_t reserved_heap_size, const ReservedSpace rs) { 778 // Check if Info level is enabled, since os::trace_page_sizes() logs on Info level. 779 if(log_is_enabled(Info, pagesize)) { 780 const size_t page_size = rs.page_size(); 781 os::trace_page_sizes("Heap", 782 MinHeapSize, 783 reserved_heap_size, 784 rs.base(), 785 rs.size(), 786 page_size); 787 } 788 } 789 790 void ParallelScavengeHeap::trace_heap(GCWhen::Type when, const GCTracer* gc_tracer) { 791 const PSHeapSummary& heap_summary = create_ps_heap_summary(); 792 gc_tracer->report_gc_heap_summary(when, heap_summary); 793 794 const MetaspaceSummary& metaspace_summary = create_metaspace_summary(); 795 gc_tracer->report_metaspace_summary(when, metaspace_summary); 796 } 797 798 CardTableBarrierSet* ParallelScavengeHeap::barrier_set() { 799 return barrier_set_cast<CardTableBarrierSet>(BarrierSet::barrier_set()); 800 } 801 802 PSCardTable* ParallelScavengeHeap::card_table() { 803 return static_cast<PSCardTable*>(barrier_set()->card_table()); 804 } 805 806 void ParallelScavengeHeap::resize_young_gen(size_t eden_size, 807 size_t survivor_size) { 808 // Delegate the resize to the generation. 809 _young_gen->resize(eden_size, survivor_size); 810 } 811 812 void ParallelScavengeHeap::resize_old_gen(size_t desired_free_space) { 813 // Delegate the resize to the generation. 814 _old_gen->resize(desired_free_space); 815 } 816 817 HeapWord* ParallelScavengeHeap::allocate_loaded_archive_space(size_t size) { 818 return _old_gen->allocate(size); 819 } 820 821 void ParallelScavengeHeap::complete_loaded_archive_space(MemRegion archive_space) { 822 assert(_old_gen->object_space()->used_region().contains(archive_space), 823 "Archive space not contained in old gen"); 824 _old_gen->complete_loaded_archive_space(archive_space); 825 } 826 827 void ParallelScavengeHeap::register_nmethod(nmethod* nm) { 828 ScavengableNMethods::register_nmethod(nm); 829 } 830 831 void ParallelScavengeHeap::unregister_nmethod(nmethod* nm) { 832 ScavengableNMethods::unregister_nmethod(nm); 833 } 834 835 void ParallelScavengeHeap::verify_nmethod(nmethod* nm) { 836 ScavengableNMethods::verify_nmethod(nm); 837 } 838 839 GrowableArray<GCMemoryManager*> ParallelScavengeHeap::memory_managers() { 840 GrowableArray<GCMemoryManager*> memory_managers(2); 841 memory_managers.append(_young_manager); 842 memory_managers.append(_old_manager); 843 return memory_managers; 844 } 845 846 GrowableArray<MemoryPool*> ParallelScavengeHeap::memory_pools() { 847 GrowableArray<MemoryPool*> memory_pools(3); 848 memory_pools.append(_eden_pool); 849 memory_pools.append(_survivor_pool); 850 memory_pools.append(_old_pool); 851 return memory_pools; 852 } 853 854 void ParallelScavengeHeap::pin_object(JavaThread* thread, oop obj) { 855 GCLocker::enter(thread); 856 } 857 858 void ParallelScavengeHeap::unpin_object(JavaThread* thread, oop obj) { 859 GCLocker::exit(thread); 860 } 861 862 void ParallelScavengeHeap::update_parallel_worker_threads_cpu_time() { 863 assert(Thread::current()->is_VM_thread(), 864 "Must be called from VM thread to avoid races"); 865 if (!UsePerfData || !os::is_thread_cpu_time_supported()) { 866 return; 867 } 868 869 // Ensure ThreadTotalCPUTimeClosure destructor is called before publishing gc 870 // time. 871 { 872 ThreadTotalCPUTimeClosure tttc(CPUTimeGroups::CPUTimeType::gc_parallel_workers); 873 // Currently parallel worker threads in GCTaskManager never terminate, so it 874 // is safe for VMThread to read their CPU times. If upstream changes this 875 // behavior, we should rethink if it is still safe. 876 gc_threads_do(&tttc); 877 } 878 879 CPUTimeCounters::publish_gc_total_cpu_time(); 880 }