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/psMarkSweepProxy.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/macros.hpp" 52 #include "utilities/vmError.hpp" 53 54 PSYoungGen* ParallelScavengeHeap::_young_gen = NULL; 55 PSOldGen* ParallelScavengeHeap::_old_gen = NULL; 56 PSAdaptiveSizePolicy* ParallelScavengeHeap::_size_policy = NULL; 57 PSGCAdaptivePolicyCounters* ParallelScavengeHeap::_gc_policy_counters = NULL; 58 GCTaskManager* ParallelScavengeHeap::_gc_task_manager = NULL; 59 60 jint ParallelScavengeHeap::initialize() { 61 const size_t heap_size = _collector_policy->max_heap_byte_size(); 62 63 ReservedSpace heap_rs = Universe::reserve_heap(heap_size, _collector_policy->heap_alignment()); 64 65 os::trace_page_sizes("Heap", 66 _collector_policy->min_heap_byte_size(), 67 heap_size, 68 generation_alignment(), 69 heap_rs.base(), 70 heap_rs.size()); 71 72 initialize_reserved_region((HeapWord*)heap_rs.base(), (HeapWord*)(heap_rs.base() + heap_rs.size())); 73 74 PSCardTable* card_table = new PSCardTable(reserved_region()); 75 card_table->initialize(); 76 CardTableBarrierSet* const barrier_set = new CardTableBarrierSet(card_table); 77 barrier_set->initialize(); 78 BarrierSet::set_barrier_set(barrier_set); 79 80 // Make up the generations 81 // Calculate the maximum size that a generation can grow. This 82 // includes growth into the other generation. Note that the 83 // parameter _max_gen_size is kept as the maximum 84 // size of the generation as the boundaries currently stand. 85 // _max_gen_size is still used as that value. 86 double max_gc_pause_sec = ((double) MaxGCPauseMillis)/1000.0; 87 double max_gc_minor_pause_sec = ((double) MaxGCMinorPauseMillis)/1000.0; 88 89 _gens = new AdjoiningGenerations(heap_rs, _collector_policy, generation_alignment()); 90 91 _old_gen = _gens->old_gen(); 92 _young_gen = _gens->young_gen(); 93 94 const size_t eden_capacity = _young_gen->eden_space()->capacity_in_bytes(); 95 const size_t old_capacity = _old_gen->capacity_in_bytes(); 96 const size_t initial_promo_size = MIN2(eden_capacity, old_capacity); 97 _size_policy = 98 new PSAdaptiveSizePolicy(eden_capacity, 99 initial_promo_size, 100 young_gen()->to_space()->capacity_in_bytes(), 101 _collector_policy->gen_alignment(), 102 max_gc_pause_sec, 103 max_gc_minor_pause_sec, 104 GCTimeRatio 105 ); 106 107 assert(!UseAdaptiveGCBoundary || 108 (old_gen()->virtual_space()->high_boundary() == 109 young_gen()->virtual_space()->low_boundary()), 110 "Boundaries must meet"); 111 // initialize the policy counters - 2 collectors, 2 generations 112 _gc_policy_counters = 113 new PSGCAdaptivePolicyCounters("ParScav:MSC", 2, 2, _size_policy); 114 115 // Set up the GCTaskManager 116 _gc_task_manager = GCTaskManager::create(ParallelGCThreads); 117 118 if (UseParallelOldGC && !PSParallelCompact::initialize()) { 119 return JNI_ENOMEM; 120 } 121 122 return JNI_OK; 123 } 124 125 void ParallelScavengeHeap::initialize_serviceability() { 126 127 _eden_pool = new EdenMutableSpacePool(_young_gen, 128 _young_gen->eden_space(), 129 "PS Eden Space", 130 false /* support_usage_threshold */); 131 132 _survivor_pool = new SurvivorMutableSpacePool(_young_gen, 133 "PS Survivor Space", 134 false /* support_usage_threshold */); 135 136 _old_pool = new PSGenerationPool(_old_gen, 137 "PS Old Gen", 138 true /* support_usage_threshold */); 139 140 _young_manager = new GCMemoryManager("PS Scavenge", "end of minor GC"); 141 _old_manager = new GCMemoryManager("PS MarkSweep", "end of major GC"); 142 143 _old_manager->add_pool(_eden_pool); 144 _old_manager->add_pool(_survivor_pool); 145 _old_manager->add_pool(_old_pool); 146 147 _young_manager->add_pool(_eden_pool); 148 _young_manager->add_pool(_survivor_pool); 149 150 } 151 152 void ParallelScavengeHeap::post_initialize() { 153 CollectedHeap::post_initialize(); 154 // Need to init the tenuring threshold 155 PSScavenge::initialize(); 156 if (UseParallelOldGC) { 157 PSParallelCompact::post_initialize(); 158 } else { 159 PSMarkSweepProxy::initialize(); 160 } 161 PSPromotionManager::initialize(); 162 } 163 164 void ParallelScavengeHeap::update_counters() { 165 young_gen()->update_counters(); 166 old_gen()->update_counters(); 167 MetaspaceCounters::update_performance_counters(); 168 CompressedClassSpaceCounters::update_performance_counters(); 169 } 170 171 size_t ParallelScavengeHeap::capacity() const { 172 size_t value = young_gen()->capacity_in_bytes() + old_gen()->capacity_in_bytes(); 173 return value; 174 } 175 176 size_t ParallelScavengeHeap::used() const { 177 size_t value = young_gen()->used_in_bytes() + old_gen()->used_in_bytes(); 178 return value; 179 } 180 181 bool ParallelScavengeHeap::is_maximal_no_gc() const { 182 return old_gen()->is_maximal_no_gc() && young_gen()->is_maximal_no_gc(); 183 } 184 185 186 size_t ParallelScavengeHeap::max_capacity() const { 187 size_t estimated = reserved_region().byte_size(); 188 if (UseAdaptiveSizePolicy) { 189 estimated -= _size_policy->max_survivor_size(young_gen()->max_size()); 190 } else { 191 estimated -= young_gen()->to_space()->capacity_in_bytes(); 192 } 193 return MAX2(estimated, capacity()); 194 } 195 196 bool ParallelScavengeHeap::is_in(const void* p) const { 197 return young_gen()->is_in(p) || old_gen()->is_in(p); 198 } 199 200 bool ParallelScavengeHeap::is_in_reserved(const void* p) const { 201 return young_gen()->is_in_reserved(p) || old_gen()->is_in_reserved(p); 202 } 203 204 // There are two levels of allocation policy here. 205 // 206 // When an allocation request fails, the requesting thread must invoke a VM 207 // operation, transfer control to the VM thread, and await the results of a 208 // garbage collection. That is quite expensive, and we should avoid doing it 209 // multiple times if possible. 210 // 211 // To accomplish this, we have a basic allocation policy, and also a 212 // failed allocation policy. 213 // 214 // The basic allocation policy controls how you allocate memory without 215 // attempting garbage collection. It is okay to grab locks and 216 // expand the heap, if that can be done without coming to a safepoint. 217 // It is likely that the basic allocation policy will not be very 218 // aggressive. 219 // 220 // The failed allocation policy is invoked from the VM thread after 221 // the basic allocation policy is unable to satisfy a mem_allocate 222 // request. This policy needs to cover the entire range of collection, 223 // heap expansion, and out-of-memory conditions. It should make every 224 // attempt to allocate the requested memory. 225 226 // Basic allocation policy. Should never be called at a safepoint, or 227 // from the VM thread. 228 // 229 // This method must handle cases where many mem_allocate requests fail 230 // simultaneously. When that happens, only one VM operation will succeed, 231 // and the rest will not be executed. For that reason, this method loops 232 // during failed allocation attempts. If the java heap becomes exhausted, 233 // we rely on the size_policy object to force a bail out. 234 HeapWord* ParallelScavengeHeap::mem_allocate( 235 size_t size, 236 bool* gc_overhead_limit_was_exceeded) { 237 assert(!SafepointSynchronize::is_at_safepoint(), "should not be at safepoint"); 238 assert(Thread::current() != (Thread*)VMThread::vm_thread(), "should not be in vm thread"); 239 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); 240 241 // In general gc_overhead_limit_was_exceeded should be false so 242 // set it so here and reset it to true only if the gc time 243 // limit is being exceeded as checked below. 244 *gc_overhead_limit_was_exceeded = false; 245 246 HeapWord* result = young_gen()->allocate(size); 247 248 uint loop_count = 0; 249 uint gc_count = 0; 250 uint gclocker_stalled_count = 0; 251 252 while (result == NULL) { 253 // We don't want to have multiple collections for a single filled generation. 254 // To prevent this, each thread tracks the total_collections() value, and if 255 // the count has changed, does not do a new collection. 256 // 257 // The collection count must be read only while holding the heap lock. VM 258 // operations also hold the heap lock during collections. There is a lock 259 // contention case where thread A blocks waiting on the Heap_lock, while 260 // thread B is holding it doing a collection. When thread A gets the lock, 261 // the collection count has already changed. To prevent duplicate collections, 262 // The policy MUST attempt allocations during the same period it reads the 263 // total_collections() value! 264 { 265 MutexLocker ml(Heap_lock); 266 gc_count = total_collections(); 267 268 result = young_gen()->allocate(size); 269 if (result != NULL) { 270 return result; 271 } 272 273 // If certain conditions hold, try allocating from the old gen. 274 result = mem_allocate_old_gen(size); 275 if (result != NULL) { 276 return result; 277 } 278 279 if (gclocker_stalled_count > GCLockerRetryAllocationCount) { 280 return NULL; 281 } 282 283 // Failed to allocate without a gc. 284 if (GCLocker::is_active_and_needs_gc()) { 285 // If this thread is not in a jni critical section, we stall 286 // the requestor until the critical section has cleared and 287 // GC allowed. When the critical section clears, a GC is 288 // initiated by the last thread exiting the critical section; so 289 // we retry the allocation sequence from the beginning of the loop, 290 // rather than causing more, now probably unnecessary, GC attempts. 291 JavaThread* jthr = JavaThread::current(); 292 if (!jthr->in_critical()) { 293 MutexUnlocker mul(Heap_lock); 294 GCLocker::stall_until_clear(); 295 gclocker_stalled_count += 1; 296 continue; 297 } else { 298 if (CheckJNICalls) { 299 fatal("Possible deadlock due to allocating while" 300 " in jni critical section"); 301 } 302 return NULL; 303 } 304 } 305 } 306 307 if (result == NULL) { 308 // Generate a VM operation 309 VM_ParallelGCFailedAllocation op(size, gc_count); 310 VMThread::execute(&op); 311 312 // Did the VM operation execute? If so, return the result directly. 313 // This prevents us from looping until time out on requests that can 314 // not be satisfied. 315 if (op.prologue_succeeded()) { 316 assert(is_in_or_null(op.result()), "result not in heap"); 317 318 // If GC was locked out during VM operation then retry allocation 319 // and/or stall as necessary. 320 if (op.gc_locked()) { 321 assert(op.result() == NULL, "must be NULL if gc_locked() is true"); 322 continue; // retry and/or stall as necessary 323 } 324 325 // Exit the loop if the gc time limit has been exceeded. 326 // The allocation must have failed above ("result" guarding 327 // this path is NULL) and the most recent collection has exceeded the 328 // gc overhead limit (although enough may have been collected to 329 // satisfy the allocation). Exit the loop so that an out-of-memory 330 // will be thrown (return a NULL ignoring the contents of 331 // op.result()), 332 // but clear gc_overhead_limit_exceeded so that the next collection 333 // starts with a clean slate (i.e., forgets about previous overhead 334 // excesses). Fill op.result() with a filler object so that the 335 // heap remains parsable. 336 const bool limit_exceeded = size_policy()->gc_overhead_limit_exceeded(); 337 const bool softrefs_clear = soft_ref_policy()->all_soft_refs_clear(); 338 339 if (limit_exceeded && softrefs_clear) { 340 *gc_overhead_limit_was_exceeded = true; 341 size_policy()->set_gc_overhead_limit_exceeded(false); 342 log_trace(gc)("ParallelScavengeHeap::mem_allocate: return NULL because gc_overhead_limit_exceeded is set"); 343 if (op.result() != NULL) { 344 CollectedHeap::fill_with_object(op.result(), size); 345 } 346 return NULL; 347 } 348 349 return op.result(); 350 } 351 } 352 353 // The policy object will prevent us from looping forever. If the 354 // time spent in gc crosses a threshold, we will bail out. 355 loop_count++; 356 if ((result == NULL) && (QueuedAllocationWarningCount > 0) && 357 (loop_count % QueuedAllocationWarningCount == 0)) { 358 log_warning(gc)("ParallelScavengeHeap::mem_allocate retries %d times", loop_count); 359 log_warning(gc)("\tsize=" SIZE_FORMAT, size); 360 } 361 } 362 363 return result; 364 } 365 366 // A "death march" is a series of ultra-slow allocations in which a full gc is 367 // done before each allocation, and after the full gc the allocation still 368 // cannot be satisfied from the young gen. This routine detects that condition; 369 // it should be called after a full gc has been done and the allocation 370 // attempted from the young gen. The parameter 'addr' should be the result of 371 // that young gen allocation attempt. 372 void 373 ParallelScavengeHeap::death_march_check(HeapWord* const addr, size_t size) { 374 if (addr != NULL) { 375 _death_march_count = 0; // death march has ended 376 } else if (_death_march_count == 0) { 377 if (should_alloc_in_eden(size)) { 378 _death_march_count = 1; // death march has started 379 } 380 } 381 } 382 383 HeapWord* ParallelScavengeHeap::mem_allocate_old_gen(size_t size) { 384 if (!should_alloc_in_eden(size) || GCLocker::is_active_and_needs_gc()) { 385 // Size is too big for eden, or gc is locked out. 386 return old_gen()->allocate(size); 387 } 388 389 // If a "death march" is in progress, allocate from the old gen a limited 390 // number of times before doing a GC. 391 if (_death_march_count > 0) { 392 if (_death_march_count < 64) { 393 ++_death_march_count; 394 return old_gen()->allocate(size); 395 } else { 396 _death_march_count = 0; 397 } 398 } 399 return NULL; 400 } 401 402 void ParallelScavengeHeap::do_full_collection(bool clear_all_soft_refs) { 403 if (UseParallelOldGC) { 404 // The do_full_collection() parameter clear_all_soft_refs 405 // is interpreted here as maximum_compaction which will 406 // cause SoftRefs to be cleared. 407 bool maximum_compaction = clear_all_soft_refs; 408 PSParallelCompact::invoke(maximum_compaction); 409 } else { 410 PSMarkSweepProxy::invoke(clear_all_soft_refs); 411 } 412 } 413 414 // Failed allocation policy. Must be called from the VM thread, and 415 // only at a safepoint! Note that this method has policy for allocation 416 // flow, and NOT collection policy. So we do not check for gc collection 417 // time over limit here, that is the responsibility of the heap specific 418 // collection methods. This method decides where to attempt allocations, 419 // and when to attempt collections, but no collection specific policy. 420 HeapWord* ParallelScavengeHeap::failed_mem_allocate(size_t size) { 421 assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); 422 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); 423 assert(!is_gc_active(), "not reentrant"); 424 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); 425 426 // We assume that allocation in eden will fail unless we collect. 427 428 // First level allocation failure, scavenge and allocate in young gen. 429 GCCauseSetter gccs(this, GCCause::_allocation_failure); 430 const bool invoked_full_gc = PSScavenge::invoke(); 431 HeapWord* result = young_gen()->allocate(size); 432 433 // Second level allocation failure. 434 // Mark sweep and allocate in young generation. 435 if (result == NULL && !invoked_full_gc) { 436 do_full_collection(false); 437 result = young_gen()->allocate(size); 438 } 439 440 death_march_check(result, size); 441 442 // Third level allocation failure. 443 // After mark sweep and young generation allocation failure, 444 // allocate in old generation. 445 if (result == NULL) { 446 result = old_gen()->allocate(size); 447 } 448 449 // Fourth level allocation failure. We're running out of memory. 450 // More complete mark sweep and allocate in young generation. 451 if (result == NULL) { 452 do_full_collection(true); 453 result = young_gen()->allocate(size); 454 } 455 456 // Fifth level allocation failure. 457 // After more complete mark sweep, allocate in old generation. 458 if (result == NULL) { 459 result = old_gen()->allocate(size); 460 } 461 462 return result; 463 } 464 465 void ParallelScavengeHeap::ensure_parsability(bool retire_tlabs) { 466 CollectedHeap::ensure_parsability(retire_tlabs); 467 young_gen()->eden_space()->ensure_parsability(); 468 } 469 470 size_t ParallelScavengeHeap::tlab_capacity(Thread* thr) const { 471 return young_gen()->eden_space()->tlab_capacity(thr); 472 } 473 474 size_t ParallelScavengeHeap::tlab_used(Thread* thr) const { 475 return young_gen()->eden_space()->tlab_used(thr); 476 } 477 478 size_t ParallelScavengeHeap::unsafe_max_tlab_alloc(Thread* thr) const { 479 return young_gen()->eden_space()->unsafe_max_tlab_alloc(thr); 480 } 481 482 HeapWord* ParallelScavengeHeap::allocate_new_tlab(size_t min_size, size_t requested_size, size_t* actual_size) { 483 HeapWord* result = young_gen()->allocate(requested_size); 484 if (result != NULL) { 485 *actual_size = requested_size; 486 } 487 488 return result; 489 } 490 491 void ParallelScavengeHeap::accumulate_statistics_all_tlabs() { 492 CollectedHeap::accumulate_statistics_all_tlabs(); 493 } 494 495 void ParallelScavengeHeap::resize_all_tlabs() { 496 CollectedHeap::resize_all_tlabs(); 497 } 498 499 // This method is used by System.gc() and JVMTI. 500 void ParallelScavengeHeap::collect(GCCause::Cause cause) { 501 assert(!Heap_lock->owned_by_self(), 502 "this thread should not own the Heap_lock"); 503 504 uint gc_count = 0; 505 uint full_gc_count = 0; 506 { 507 MutexLocker ml(Heap_lock); 508 // This value is guarded by the Heap_lock 509 gc_count = total_collections(); 510 full_gc_count = total_full_collections(); 511 } 512 513 VM_ParallelGCSystemGC op(gc_count, full_gc_count, cause); 514 VMThread::execute(&op); 515 } 516 517 void ParallelScavengeHeap::object_iterate(ObjectClosure* cl) { 518 young_gen()->object_iterate(cl); 519 old_gen()->object_iterate(cl); 520 } 521 522 523 HeapWord* ParallelScavengeHeap::block_start(const void* addr) const { 524 if (young_gen()->is_in_reserved(addr)) { 525 assert(young_gen()->is_in(addr), 526 "addr should be in allocated part of young gen"); 527 // called from os::print_location by find or VMError 528 if (Debugging || VMError::fatal_error_in_progress()) return NULL; 529 Unimplemented(); 530 } else if (old_gen()->is_in_reserved(addr)) { 531 assert(old_gen()->is_in(addr), 532 "addr should be in allocated part of old gen"); 533 return old_gen()->start_array()->object_start((HeapWord*)addr); 534 } 535 return 0; 536 } 537 538 size_t ParallelScavengeHeap::block_size(const HeapWord* addr) const { 539 return oop(addr)->size(); 540 } 541 542 bool ParallelScavengeHeap::block_is_obj(const HeapWord* addr) const { 543 return block_start(addr) == addr; 544 } 545 546 jlong ParallelScavengeHeap::millis_since_last_gc() { 547 return UseParallelOldGC ? 548 PSParallelCompact::millis_since_last_gc() : 549 PSMarkSweepProxy::millis_since_last_gc(); 550 } 551 552 void ParallelScavengeHeap::prepare_for_verify() { 553 ensure_parsability(false); // no need to retire TLABs for verification 554 } 555 556 PSHeapSummary ParallelScavengeHeap::create_ps_heap_summary() { 557 PSOldGen* old = old_gen(); 558 HeapWord* old_committed_end = (HeapWord*)old->virtual_space()->committed_high_addr(); 559 VirtualSpaceSummary old_summary(old->reserved().start(), old_committed_end, old->reserved().end()); 560 SpaceSummary old_space(old->reserved().start(), old_committed_end, old->used_in_bytes()); 561 562 PSYoungGen* young = young_gen(); 563 VirtualSpaceSummary young_summary(young->reserved().start(), 564 (HeapWord*)young->virtual_space()->committed_high_addr(), young->reserved().end()); 565 566 MutableSpace* eden = young_gen()->eden_space(); 567 SpaceSummary eden_space(eden->bottom(), eden->end(), eden->used_in_bytes()); 568 569 MutableSpace* from = young_gen()->from_space(); 570 SpaceSummary from_space(from->bottom(), from->end(), from->used_in_bytes()); 571 572 MutableSpace* to = young_gen()->to_space(); 573 SpaceSummary to_space(to->bottom(), to->end(), to->used_in_bytes()); 574 575 VirtualSpaceSummary heap_summary = create_heap_space_summary(); 576 return PSHeapSummary(heap_summary, used(), old_summary, old_space, young_summary, eden_space, from_space, to_space); 577 } 578 579 void ParallelScavengeHeap::print_on(outputStream* st) const { 580 young_gen()->print_on(st); 581 old_gen()->print_on(st); 582 MetaspaceUtils::print_on(st); 583 } 584 585 void ParallelScavengeHeap::print_on_error(outputStream* st) const { 586 this->CollectedHeap::print_on_error(st); 587 588 if (UseParallelOldGC) { 589 st->cr(); 590 PSParallelCompact::print_on_error(st); 591 } 592 } 593 594 void ParallelScavengeHeap::gc_threads_do(ThreadClosure* tc) const { 595 PSScavenge::gc_task_manager()->threads_do(tc); 596 } 597 598 void ParallelScavengeHeap::print_gc_threads_on(outputStream* st) const { 599 PSScavenge::gc_task_manager()->print_threads_on(st); 600 } 601 602 void ParallelScavengeHeap::print_tracing_info() const { 603 AdaptiveSizePolicyOutput::print(); 604 log_debug(gc, heap, exit)("Accumulated young generation GC time %3.7f secs", PSScavenge::accumulated_time()->seconds()); 605 log_debug(gc, heap, exit)("Accumulated old generation GC time %3.7f secs", 606 UseParallelOldGC ? PSParallelCompact::accumulated_time()->seconds() : PSMarkSweepProxy::accumulated_time()->seconds()); 607 } 608 609 610 void ParallelScavengeHeap::verify(VerifyOption option /* ignored */) { 611 // Why do we need the total_collections()-filter below? 612 if (total_collections() > 0) { 613 log_debug(gc, verify)("Tenured"); 614 old_gen()->verify(); 615 616 log_debug(gc, verify)("Eden"); 617 young_gen()->verify(); 618 } 619 } 620 621 void ParallelScavengeHeap::trace_heap(GCWhen::Type when, const GCTracer* gc_tracer) { 622 const PSHeapSummary& heap_summary = create_ps_heap_summary(); 623 gc_tracer->report_gc_heap_summary(when, heap_summary); 624 625 const MetaspaceSummary& metaspace_summary = create_metaspace_summary(); 626 gc_tracer->report_metaspace_summary(when, metaspace_summary); 627 } 628 629 ParallelScavengeHeap* ParallelScavengeHeap::heap() { 630 CollectedHeap* heap = Universe::heap(); 631 assert(heap != NULL, "Uninitialized access to ParallelScavengeHeap::heap()"); 632 assert(heap->kind() == CollectedHeap::Parallel, "Invalid name"); 633 return (ParallelScavengeHeap*)heap; 634 } 635 636 CardTableBarrierSet* ParallelScavengeHeap::barrier_set() { 637 return barrier_set_cast<CardTableBarrierSet>(BarrierSet::barrier_set()); 638 } 639 640 PSCardTable* ParallelScavengeHeap::card_table() { 641 return static_cast<PSCardTable*>(barrier_set()->card_table()); 642 } 643 644 // Before delegating the resize to the young generation, 645 // the reserved space for the young and old generations 646 // may be changed to accommodate the desired resize. 647 void ParallelScavengeHeap::resize_young_gen(size_t eden_size, 648 size_t survivor_size) { 649 if (UseAdaptiveGCBoundary) { 650 if (size_policy()->bytes_absorbed_from_eden() != 0) { 651 size_policy()->reset_bytes_absorbed_from_eden(); 652 return; // The generation changed size already. 653 } 654 gens()->adjust_boundary_for_young_gen_needs(eden_size, survivor_size); 655 } 656 657 // Delegate the resize to the generation. 658 _young_gen->resize(eden_size, survivor_size); 659 } 660 661 // Before delegating the resize to the old generation, 662 // the reserved space for the young and old generations 663 // may be changed to accommodate the desired resize. 664 void ParallelScavengeHeap::resize_old_gen(size_t desired_free_space) { 665 if (UseAdaptiveGCBoundary) { 666 if (size_policy()->bytes_absorbed_from_eden() != 0) { 667 size_policy()->reset_bytes_absorbed_from_eden(); 668 return; // The generation changed size already. 669 } 670 gens()->adjust_boundary_for_old_gen_needs(desired_free_space); 671 } 672 673 // Delegate the resize to the generation. 674 _old_gen->resize(desired_free_space); 675 } 676 677 ParallelScavengeHeap::ParStrongRootsScope::ParStrongRootsScope() { 678 // nothing particular 679 } 680 681 ParallelScavengeHeap::ParStrongRootsScope::~ParStrongRootsScope() { 682 // nothing particular 683 } 684 685 #ifndef PRODUCT 686 void ParallelScavengeHeap::record_gen_tops_before_GC() { 687 if (ZapUnusedHeapArea) { 688 young_gen()->record_spaces_top(); 689 old_gen()->record_spaces_top(); 690 } 691 } 692 693 void ParallelScavengeHeap::gen_mangle_unused_area() { 694 if (ZapUnusedHeapArea) { 695 young_gen()->eden_space()->mangle_unused_area(); 696 young_gen()->to_space()->mangle_unused_area(); 697 young_gen()->from_space()->mangle_unused_area(); 698 old_gen()->object_space()->mangle_unused_area(); 699 } 700 } 701 #endif 702 703 bool ParallelScavengeHeap::is_scavengable(oop obj) { 704 return is_in_young(obj); 705 } 706 707 void ParallelScavengeHeap::register_nmethod(nmethod* nm) { 708 CodeCache::register_scavenge_root_nmethod(nm); 709 } 710 711 void ParallelScavengeHeap::verify_nmethod(nmethod* nm) { 712 CodeCache::verify_scavenge_root_nmethod(nm); 713 } 714 715 GrowableArray<GCMemoryManager*> ParallelScavengeHeap::memory_managers() { 716 GrowableArray<GCMemoryManager*> memory_managers(2); 717 memory_managers.append(_young_manager); 718 memory_managers.append(_old_manager); 719 return memory_managers; 720 } 721 722 GrowableArray<MemoryPool*> ParallelScavengeHeap::memory_pools() { 723 GrowableArray<MemoryPool*> memory_pools(3); 724 memory_pools.append(_eden_pool); 725 memory_pools.append(_survivor_pool); 726 memory_pools.append(_old_pool); 727 return memory_pools; 728 }