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/adjoiningGenerationsForHeteroHeap.hpp" 29 #include "gc/parallel/adjoiningVirtualSpaces.hpp" 30 #include "gc/parallel/gcTaskManager.hpp" 31 #include "gc/parallel/generationSizer.hpp" 32 #include "gc/parallel/objectStartArray.inline.hpp" 33 #include "gc/parallel/parallelScavengeHeap.inline.hpp" 34 #include "gc/parallel/psAdaptiveSizePolicy.hpp" 35 #include "gc/parallel/psMarkSweepProxy.hpp" 36 #include "gc/parallel/psMemoryPool.hpp" 37 #include "gc/parallel/psParallelCompact.inline.hpp" 38 #include "gc/parallel/psPromotionManager.hpp" 39 #include "gc/parallel/psScavenge.hpp" 40 #include "gc/parallel/psVMOperations.hpp" 41 #include "gc/shared/gcHeapSummary.hpp" 42 #include "gc/shared/gcLocker.hpp" 43 #include "gc/shared/gcWhen.hpp" 44 #include "logging/log.hpp" 45 #include "memory/metaspaceCounters.hpp" 46 #include "oops/oop.inline.hpp" 47 #include "runtime/handles.inline.hpp" 48 #include "runtime/java.hpp" 49 #include "runtime/vmThread.hpp" 50 #include "services/memoryManager.hpp" 51 #include "services/memTracker.hpp" 52 #include "utilities/macros.hpp" 53 #include "utilities/vmError.hpp" 54 55 PSYoungGen* ParallelScavengeHeap::_young_gen = NULL; 56 PSOldGen* ParallelScavengeHeap::_old_gen = NULL; 57 PSAdaptiveSizePolicy* ParallelScavengeHeap::_size_policy = NULL; 58 PSGCAdaptivePolicyCounters* ParallelScavengeHeap::_gc_policy_counters = NULL; 59 GCTaskManager* ParallelScavengeHeap::_gc_task_manager = NULL; 60 61 jint ParallelScavengeHeap::initialize() { 62 size_t heap_size = _collector_policy->heap_reserved_size_bytes(); 63 64 ReservedSpace heap_rs = Universe::reserve_heap(heap_size, _collector_policy->heap_alignment()); 65 66 os::trace_page_sizes("Heap", 67 _collector_policy->min_heap_byte_size(), 68 heap_size, 69 generation_alignment(), 70 heap_rs.base(), 71 heap_rs.size()); 72 73 initialize_reserved_region((HeapWord*)heap_rs.base(), (HeapWord*)(heap_rs.base() + heap_rs.size())); 74 75 PSCardTable* card_table = new PSCardTable(reserved_region()); 76 card_table->initialize(); 77 CardTableBarrierSet* const barrier_set = new CardTableBarrierSet(card_table); 78 barrier_set->initialize(); 79 BarrierSet::set_barrier_set(barrier_set); 80 81 // Make up the generations 82 // Calculate the maximum size that a generation can grow. This 83 // includes growth into the other generation. Note that the 84 // parameter _max_gen_size is kept as the maximum 85 // size of the generation as the boundaries currently stand. 86 // _max_gen_size is still used as that value. 87 double max_gc_pause_sec = ((double) MaxGCPauseMillis)/1000.0; 88 double max_gc_minor_pause_sec = ((double) MaxGCMinorPauseMillis)/1000.0; 89 90 _gens = AdjoiningGenerations::create_adjoining_generations(heap_rs, _collector_policy, generation_alignment()); 91 92 _old_gen = _gens->old_gen(); 93 _young_gen = _gens->young_gen(); 94 95 const size_t eden_capacity = _young_gen->eden_space()->capacity_in_bytes(); 96 const size_t old_capacity = _old_gen->capacity_in_bytes(); 97 const size_t initial_promo_size = MIN2(eden_capacity, old_capacity); 98 _size_policy = 99 new PSAdaptiveSizePolicy(eden_capacity, 100 initial_promo_size, 101 young_gen()->to_space()->capacity_in_bytes(), 102 _collector_policy->gen_alignment(), 103 max_gc_pause_sec, 104 max_gc_minor_pause_sec, 105 GCTimeRatio 106 ); 107 108 assert(_collector_policy->is_hetero_heap() || !UseAdaptiveGCBoundary || 109 (old_gen()->virtual_space()->high_boundary() == 110 young_gen()->virtual_space()->low_boundary()), 111 "Boundaries must meet"); 112 // initialize the policy counters - 2 collectors, 2 generations 113 _gc_policy_counters = 114 new PSGCAdaptivePolicyCounters("ParScav:MSC", 2, 2, _size_policy); 115 116 // Set up the GCTaskManager 117 _gc_task_manager = GCTaskManager::create(ParallelGCThreads); 118 119 if (UseParallelOldGC && !PSParallelCompact::initialize()) { 120 return JNI_ENOMEM; 121 } 122 123 return JNI_OK; 124 } 125 126 void ParallelScavengeHeap::initialize_serviceability() { 127 128 _eden_pool = new EdenMutableSpacePool(_young_gen, 129 _young_gen->eden_space(), 130 "PS Eden Space", 131 false /* support_usage_threshold */); 132 133 _survivor_pool = new SurvivorMutableSpacePool(_young_gen, 134 "PS Survivor Space", 135 false /* support_usage_threshold */); 136 137 _old_pool = new PSGenerationPool(_old_gen, 138 "PS Old Gen", 139 true /* support_usage_threshold */); 140 141 _young_manager = new GCMemoryManager("PS Scavenge", "end of minor GC"); 142 _old_manager = new GCMemoryManager("PS MarkSweep", "end of major GC"); 143 144 _old_manager->add_pool(_eden_pool); 145 _old_manager->add_pool(_survivor_pool); 146 _old_manager->add_pool(_old_pool); 147 148 _young_manager->add_pool(_eden_pool); 149 _young_manager->add_pool(_survivor_pool); 150 151 } 152 153 void ParallelScavengeHeap::post_initialize() { 154 CollectedHeap::post_initialize(); 155 // Need to init the tenuring threshold 156 PSScavenge::initialize(); 157 if (UseParallelOldGC) { 158 PSParallelCompact::post_initialize(); 159 } else { 160 PSMarkSweepProxy::initialize(); 161 } 162 PSPromotionManager::initialize(); 163 } 164 165 void ParallelScavengeHeap::update_counters() { 166 young_gen()->update_counters(); 167 old_gen()->update_counters(); 168 MetaspaceCounters::update_performance_counters(); 169 CompressedClassSpaceCounters::update_performance_counters(); 170 } 171 172 size_t ParallelScavengeHeap::capacity() const { 173 size_t value = young_gen()->capacity_in_bytes() + old_gen()->capacity_in_bytes(); 174 return value; 175 } 176 177 size_t ParallelScavengeHeap::used() const { 178 size_t value = young_gen()->used_in_bytes() + old_gen()->used_in_bytes(); 179 return value; 180 } 181 182 bool ParallelScavengeHeap::is_maximal_no_gc() const { 183 return old_gen()->is_maximal_no_gc() && young_gen()->is_maximal_no_gc(); 184 } 185 186 187 size_t ParallelScavengeHeap::max_capacity() const { 188 size_t estimated = reserved_region().byte_size(); 189 if (UseAdaptiveSizePolicy) { 190 estimated -= _size_policy->max_survivor_size(young_gen()->max_size()); 191 } else { 192 estimated -= young_gen()->to_space()->capacity_in_bytes(); 193 } 194 return MAX2(estimated, capacity()); 195 } 196 197 bool ParallelScavengeHeap::is_in(const void* p) const { 198 return young_gen()->is_in(p) || old_gen()->is_in(p); 199 } 200 201 bool ParallelScavengeHeap::is_in_reserved(const void* p) const { 202 return young_gen()->is_in_reserved(p) || old_gen()->is_in_reserved(p); 203 } 204 205 // There are two levels of allocation policy here. 206 // 207 // When an allocation request fails, the requesting thread must invoke a VM 208 // operation, transfer control to the VM thread, and await the results of a 209 // garbage collection. That is quite expensive, and we should avoid doing it 210 // multiple times if possible. 211 // 212 // To accomplish this, we have a basic allocation policy, and also a 213 // failed allocation policy. 214 // 215 // The basic allocation policy controls how you allocate memory without 216 // attempting garbage collection. It is okay to grab locks and 217 // expand the heap, if that can be done without coming to a safepoint. 218 // It is likely that the basic allocation policy will not be very 219 // aggressive. 220 // 221 // The failed allocation policy is invoked from the VM thread after 222 // the basic allocation policy is unable to satisfy a mem_allocate 223 // request. This policy needs to cover the entire range of collection, 224 // heap expansion, and out-of-memory conditions. It should make every 225 // attempt to allocate the requested memory. 226 227 // Basic allocation policy. Should never be called at a safepoint, or 228 // from the VM thread. 229 // 230 // This method must handle cases where many mem_allocate requests fail 231 // simultaneously. When that happens, only one VM operation will succeed, 232 // and the rest will not be executed. For that reason, this method loops 233 // during failed allocation attempts. If the java heap becomes exhausted, 234 // we rely on the size_policy object to force a bail out. 235 HeapWord* ParallelScavengeHeap::mem_allocate( 236 size_t size, 237 bool* gc_overhead_limit_was_exceeded) { 238 assert(!SafepointSynchronize::is_at_safepoint(), "should not be at safepoint"); 239 assert(Thread::current() != (Thread*)VMThread::vm_thread(), "should not be in vm thread"); 240 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); 241 242 // In general gc_overhead_limit_was_exceeded should be false so 243 // set it so here and reset it to true only if the gc time 244 // limit is being exceeded as checked below. 245 *gc_overhead_limit_was_exceeded = false; 246 247 HeapWord* result = young_gen()->allocate(size); 248 249 uint loop_count = 0; 250 uint gc_count = 0; 251 uint gclocker_stalled_count = 0; 252 253 while (result == NULL) { 254 // We don't want to have multiple collections for a single filled generation. 255 // To prevent this, each thread tracks the total_collections() value, and if 256 // the count has changed, does not do a new collection. 257 // 258 // The collection count must be read only while holding the heap lock. VM 259 // operations also hold the heap lock during collections. There is a lock 260 // contention case where thread A blocks waiting on the Heap_lock, while 261 // thread B is holding it doing a collection. When thread A gets the lock, 262 // the collection count has already changed. To prevent duplicate collections, 263 // The policy MUST attempt allocations during the same period it reads the 264 // total_collections() value! 265 { 266 MutexLocker ml(Heap_lock); 267 gc_count = total_collections(); 268 269 result = young_gen()->allocate(size); 270 if (result != NULL) { 271 return result; 272 } 273 274 // If certain conditions hold, try allocating from the old gen. 275 result = mem_allocate_old_gen(size); 276 if (result != NULL) { 277 return result; 278 } 279 280 if (gclocker_stalled_count > GCLockerRetryAllocationCount) { 281 return NULL; 282 } 283 284 // Failed to allocate without a gc. 285 if (GCLocker::is_active_and_needs_gc()) { 286 // If this thread is not in a jni critical section, we stall 287 // the requestor until the critical section has cleared and 288 // GC allowed. When the critical section clears, a GC is 289 // initiated by the last thread exiting the critical section; so 290 // we retry the allocation sequence from the beginning of the loop, 291 // rather than causing more, now probably unnecessary, GC attempts. 292 JavaThread* jthr = JavaThread::current(); 293 if (!jthr->in_critical()) { 294 MutexUnlocker mul(Heap_lock); 295 GCLocker::stall_until_clear(); 296 gclocker_stalled_count += 1; 297 continue; 298 } else { 299 if (CheckJNICalls) { 300 fatal("Possible deadlock due to allocating while" 301 " in jni critical section"); 302 } 303 return NULL; 304 } 305 } 306 } 307 308 if (result == NULL) { 309 // Generate a VM operation 310 VM_ParallelGCFailedAllocation op(size, gc_count); 311 VMThread::execute(&op); 312 313 // Did the VM operation execute? If so, return the result directly. 314 // This prevents us from looping until time out on requests that can 315 // not be satisfied. 316 if (op.prologue_succeeded()) { 317 assert(is_in_or_null(op.result()), "result not in heap"); 318 319 // If GC was locked out during VM operation then retry allocation 320 // and/or stall as necessary. 321 if (op.gc_locked()) { 322 assert(op.result() == NULL, "must be NULL if gc_locked() is true"); 323 continue; // retry and/or stall as necessary 324 } 325 326 // Exit the loop if the gc time limit has been exceeded. 327 // The allocation must have failed above ("result" guarding 328 // this path is NULL) and the most recent collection has exceeded the 329 // gc overhead limit (although enough may have been collected to 330 // satisfy the allocation). Exit the loop so that an out-of-memory 331 // will be thrown (return a NULL ignoring the contents of 332 // op.result()), 333 // but clear gc_overhead_limit_exceeded so that the next collection 334 // starts with a clean slate (i.e., forgets about previous overhead 335 // excesses). Fill op.result() with a filler object so that the 336 // heap remains parsable. 337 const bool limit_exceeded = size_policy()->gc_overhead_limit_exceeded(); 338 const bool softrefs_clear = soft_ref_policy()->all_soft_refs_clear(); 339 340 if (limit_exceeded && softrefs_clear) { 341 *gc_overhead_limit_was_exceeded = true; 342 size_policy()->set_gc_overhead_limit_exceeded(false); 343 log_trace(gc)("ParallelScavengeHeap::mem_allocate: return NULL because gc_overhead_limit_exceeded is set"); 344 if (op.result() != NULL) { 345 CollectedHeap::fill_with_object(op.result(), size); 346 } 347 return NULL; 348 } 349 350 return op.result(); 351 } 352 } 353 354 // The policy object will prevent us from looping forever. If the 355 // time spent in gc crosses a threshold, we will bail out. 356 loop_count++; 357 if ((result == NULL) && (QueuedAllocationWarningCount > 0) && 358 (loop_count % QueuedAllocationWarningCount == 0)) { 359 log_warning(gc)("ParallelScavengeHeap::mem_allocate retries %d times", loop_count); 360 log_warning(gc)("\tsize=" SIZE_FORMAT, size); 361 } 362 } 363 364 return result; 365 } 366 367 // A "death march" is a series of ultra-slow allocations in which a full gc is 368 // done before each allocation, and after the full gc the allocation still 369 // cannot be satisfied from the young gen. This routine detects that condition; 370 // it should be called after a full gc has been done and the allocation 371 // attempted from the young gen. The parameter 'addr' should be the result of 372 // that young gen allocation attempt. 373 void 374 ParallelScavengeHeap::death_march_check(HeapWord* const addr, size_t size) { 375 if (addr != NULL) { 376 _death_march_count = 0; // death march has ended 377 } else if (_death_march_count == 0) { 378 if (should_alloc_in_eden(size)) { 379 _death_march_count = 1; // death march has started 380 } 381 } 382 } 383 384 HeapWord* ParallelScavengeHeap::mem_allocate_old_gen(size_t size) { 385 if (!should_alloc_in_eden(size) || GCLocker::is_active_and_needs_gc()) { 386 // Size is too big for eden, or gc is locked out. 387 return old_gen()->allocate(size); 388 } 389 390 // If a "death march" is in progress, allocate from the old gen a limited 391 // number of times before doing a GC. 392 if (_death_march_count > 0) { 393 if (_death_march_count < 64) { 394 ++_death_march_count; 395 return old_gen()->allocate(size); 396 } else { 397 _death_march_count = 0; 398 } 399 } 400 return NULL; 401 } 402 403 void ParallelScavengeHeap::do_full_collection(bool clear_all_soft_refs) { 404 if (UseParallelOldGC) { 405 // The do_full_collection() parameter clear_all_soft_refs 406 // is interpreted here as maximum_compaction which will 407 // cause SoftRefs to be cleared. 408 bool maximum_compaction = clear_all_soft_refs; 409 PSParallelCompact::invoke(maximum_compaction); 410 } else { 411 PSMarkSweepProxy::invoke(clear_all_soft_refs); 412 } 413 } 414 415 // Failed allocation policy. Must be called from the VM thread, and 416 // only at a safepoint! Note that this method has policy for allocation 417 // flow, and NOT collection policy. So we do not check for gc collection 418 // time over limit here, that is the responsibility of the heap specific 419 // collection methods. This method decides where to attempt allocations, 420 // and when to attempt collections, but no collection specific policy. 421 HeapWord* ParallelScavengeHeap::failed_mem_allocate(size_t size) { 422 assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); 423 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); 424 assert(!is_gc_active(), "not reentrant"); 425 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); 426 427 // We assume that allocation in eden will fail unless we collect. 428 429 // First level allocation failure, scavenge and allocate in young gen. 430 GCCauseSetter gccs(this, GCCause::_allocation_failure); 431 const bool invoked_full_gc = PSScavenge::invoke(); 432 HeapWord* result = young_gen()->allocate(size); 433 434 // Second level allocation failure. 435 // Mark sweep and allocate in young generation. 436 if (result == NULL && !invoked_full_gc) { 437 do_full_collection(false); 438 result = young_gen()->allocate(size); 439 } 440 441 death_march_check(result, size); 442 443 // Third level allocation failure. 444 // After mark sweep and young generation allocation failure, 445 // allocate in old generation. 446 if (result == NULL) { 447 result = old_gen()->allocate(size); 448 } 449 450 // Fourth level allocation failure. We're running out of memory. 451 // More complete mark sweep and allocate in young generation. 452 if (result == NULL) { 453 do_full_collection(true); 454 result = young_gen()->allocate(size); 455 } 456 457 // Fifth level allocation failure. 458 // After more complete mark sweep, allocate in old generation. 459 if (result == NULL) { 460 result = old_gen()->allocate(size); 461 } 462 463 return result; 464 } 465 466 void ParallelScavengeHeap::ensure_parsability(bool retire_tlabs) { 467 CollectedHeap::ensure_parsability(retire_tlabs); 468 young_gen()->eden_space()->ensure_parsability(); 469 } 470 471 size_t ParallelScavengeHeap::tlab_capacity(Thread* thr) const { 472 return young_gen()->eden_space()->tlab_capacity(thr); 473 } 474 475 size_t ParallelScavengeHeap::tlab_used(Thread* thr) const { 476 return young_gen()->eden_space()->tlab_used(thr); 477 } 478 479 size_t ParallelScavengeHeap::unsafe_max_tlab_alloc(Thread* thr) const { 480 return young_gen()->eden_space()->unsafe_max_tlab_alloc(thr); 481 } 482 483 HeapWord* ParallelScavengeHeap::allocate_new_tlab(size_t min_size, size_t requested_size, size_t* actual_size) { 484 HeapWord* result = young_gen()->allocate(requested_size); 485 if (result != NULL) { 486 *actual_size = requested_size; 487 } 488 489 return result; 490 } 491 492 void ParallelScavengeHeap::resize_all_tlabs() { 493 CollectedHeap::resize_all_tlabs(); 494 } 495 496 // This method is used by System.gc() and JVMTI. 497 void ParallelScavengeHeap::collect(GCCause::Cause cause) { 498 assert(!Heap_lock->owned_by_self(), 499 "this thread should not own the Heap_lock"); 500 501 uint gc_count = 0; 502 uint full_gc_count = 0; 503 { 504 MutexLocker ml(Heap_lock); 505 // This value is guarded by the Heap_lock 506 gc_count = total_collections(); 507 full_gc_count = total_full_collections(); 508 } 509 510 VM_ParallelGCSystemGC op(gc_count, full_gc_count, cause); 511 VMThread::execute(&op); 512 } 513 514 void ParallelScavengeHeap::object_iterate(ObjectClosure* cl) { 515 young_gen()->object_iterate(cl); 516 old_gen()->object_iterate(cl); 517 } 518 519 520 HeapWord* ParallelScavengeHeap::block_start(const void* addr) const { 521 if (young_gen()->is_in_reserved(addr)) { 522 assert(young_gen()->is_in(addr), 523 "addr should be in allocated part of young gen"); 524 // called from os::print_location by find or VMError 525 if (Debugging || VMError::fatal_error_in_progress()) return NULL; 526 Unimplemented(); 527 } else if (old_gen()->is_in_reserved(addr)) { 528 assert(old_gen()->is_in(addr), 529 "addr should be in allocated part of old gen"); 530 return old_gen()->start_array()->object_start((HeapWord*)addr); 531 } 532 return 0; 533 } 534 535 size_t ParallelScavengeHeap::block_size(const HeapWord* addr) const { 536 return oop(addr)->size(); 537 } 538 539 bool ParallelScavengeHeap::block_is_obj(const HeapWord* addr) const { 540 return block_start(addr) == addr; 541 } 542 543 jlong ParallelScavengeHeap::millis_since_last_gc() { 544 return UseParallelOldGC ? 545 PSParallelCompact::millis_since_last_gc() : 546 PSMarkSweepProxy::millis_since_last_gc(); 547 } 548 549 void ParallelScavengeHeap::prepare_for_verify() { 550 ensure_parsability(false); // no need to retire TLABs for verification 551 } 552 553 PSHeapSummary ParallelScavengeHeap::create_ps_heap_summary() { 554 PSOldGen* old = old_gen(); 555 HeapWord* old_committed_end = (HeapWord*)old->virtual_space()->committed_high_addr(); 556 VirtualSpaceSummary old_summary(old->reserved().start(), old_committed_end, old->reserved().end()); 557 SpaceSummary old_space(old->reserved().start(), old_committed_end, old->used_in_bytes()); 558 559 PSYoungGen* young = young_gen(); 560 VirtualSpaceSummary young_summary(young->reserved().start(), 561 (HeapWord*)young->virtual_space()->committed_high_addr(), young->reserved().end()); 562 563 MutableSpace* eden = young_gen()->eden_space(); 564 SpaceSummary eden_space(eden->bottom(), eden->end(), eden->used_in_bytes()); 565 566 MutableSpace* from = young_gen()->from_space(); 567 SpaceSummary from_space(from->bottom(), from->end(), from->used_in_bytes()); 568 569 MutableSpace* to = young_gen()->to_space(); 570 SpaceSummary to_space(to->bottom(), to->end(), to->used_in_bytes()); 571 572 VirtualSpaceSummary heap_summary = create_heap_space_summary(); 573 return PSHeapSummary(heap_summary, used(), old_summary, old_space, young_summary, eden_space, from_space, to_space); 574 } 575 576 void ParallelScavengeHeap::print_on(outputStream* st) const { 577 young_gen()->print_on(st); 578 old_gen()->print_on(st); 579 MetaspaceUtils::print_on(st); 580 } 581 582 void ParallelScavengeHeap::print_on_error(outputStream* st) const { 583 this->CollectedHeap::print_on_error(st); 584 585 if (UseParallelOldGC) { 586 st->cr(); 587 PSParallelCompact::print_on_error(st); 588 } 589 } 590 591 void ParallelScavengeHeap::gc_threads_do(ThreadClosure* tc) const { 592 PSScavenge::gc_task_manager()->threads_do(tc); 593 } 594 595 void ParallelScavengeHeap::print_gc_threads_on(outputStream* st) const { 596 PSScavenge::gc_task_manager()->print_threads_on(st); 597 } 598 599 void ParallelScavengeHeap::print_tracing_info() const { 600 AdaptiveSizePolicyOutput::print(); 601 log_debug(gc, heap, exit)("Accumulated young generation GC time %3.7f secs", PSScavenge::accumulated_time()->seconds()); 602 log_debug(gc, heap, exit)("Accumulated old generation GC time %3.7f secs", 603 UseParallelOldGC ? PSParallelCompact::accumulated_time()->seconds() : PSMarkSweepProxy::accumulated_time()->seconds()); 604 } 605 606 607 void ParallelScavengeHeap::verify(VerifyOption option /* ignored */) { 608 // Why do we need the total_collections()-filter below? 609 if (total_collections() > 0) { 610 log_debug(gc, verify)("Tenured"); 611 old_gen()->verify(); 612 613 log_debug(gc, verify)("Eden"); 614 young_gen()->verify(); 615 } 616 } 617 618 void ParallelScavengeHeap::trace_heap(GCWhen::Type when, const GCTracer* gc_tracer) { 619 const PSHeapSummary& heap_summary = create_ps_heap_summary(); 620 gc_tracer->report_gc_heap_summary(when, heap_summary); 621 622 const MetaspaceSummary& metaspace_summary = create_metaspace_summary(); 623 gc_tracer->report_metaspace_summary(when, metaspace_summary); 624 } 625 626 ParallelScavengeHeap* ParallelScavengeHeap::heap() { 627 CollectedHeap* heap = Universe::heap(); 628 assert(heap != NULL, "Uninitialized access to ParallelScavengeHeap::heap()"); 629 assert(heap->kind() == CollectedHeap::Parallel, "Invalid name"); 630 return (ParallelScavengeHeap*)heap; 631 } 632 633 CardTableBarrierSet* ParallelScavengeHeap::barrier_set() { 634 return barrier_set_cast<CardTableBarrierSet>(BarrierSet::barrier_set()); 635 } 636 637 PSCardTable* ParallelScavengeHeap::card_table() { 638 return static_cast<PSCardTable*>(barrier_set()->card_table()); 639 } 640 641 // Before delegating the resize to the young generation, 642 // the reserved space for the young and old generations 643 // may be changed to accommodate the desired resize. 644 void ParallelScavengeHeap::resize_young_gen(size_t eden_size, 645 size_t survivor_size) { 646 if (UseAdaptiveGCBoundary) { 647 if (size_policy()->bytes_absorbed_from_eden() != 0) { 648 size_policy()->reset_bytes_absorbed_from_eden(); 649 return; // The generation changed size already. 650 } 651 gens()->adjust_boundary_for_young_gen_needs(eden_size, survivor_size); 652 } 653 654 // Delegate the resize to the generation. 655 _young_gen->resize(eden_size, survivor_size); 656 } 657 658 // Before delegating the resize to the old generation, 659 // the reserved space for the young and old generations 660 // may be changed to accommodate the desired resize. 661 void ParallelScavengeHeap::resize_old_gen(size_t desired_free_space) { 662 if (UseAdaptiveGCBoundary) { 663 if (size_policy()->bytes_absorbed_from_eden() != 0) { 664 size_policy()->reset_bytes_absorbed_from_eden(); 665 return; // The generation changed size already. 666 } 667 gens()->adjust_boundary_for_old_gen_needs(desired_free_space); 668 } 669 670 // Delegate the resize to the generation. 671 _old_gen->resize(desired_free_space); 672 } 673 674 ParallelScavengeHeap::ParStrongRootsScope::ParStrongRootsScope() { 675 // nothing particular 676 } 677 678 ParallelScavengeHeap::ParStrongRootsScope::~ParStrongRootsScope() { 679 // nothing particular 680 } 681 682 #ifndef PRODUCT 683 void ParallelScavengeHeap::record_gen_tops_before_GC() { 684 if (ZapUnusedHeapArea) { 685 young_gen()->record_spaces_top(); 686 old_gen()->record_spaces_top(); 687 } 688 } 689 690 void ParallelScavengeHeap::gen_mangle_unused_area() { 691 if (ZapUnusedHeapArea) { 692 young_gen()->eden_space()->mangle_unused_area(); 693 young_gen()->to_space()->mangle_unused_area(); 694 young_gen()->from_space()->mangle_unused_area(); 695 old_gen()->object_space()->mangle_unused_area(); 696 } 697 } 698 #endif 699 700 bool ParallelScavengeHeap::is_scavengable(oop obj) { 701 return is_in_young(obj); 702 } 703 704 void ParallelScavengeHeap::register_nmethod(nmethod* nm) { 705 CodeCache::register_scavenge_root_nmethod(nm); 706 } 707 708 void ParallelScavengeHeap::verify_nmethod(nmethod* nm) { 709 CodeCache::verify_scavenge_root_nmethod(nm); 710 } 711 712 GrowableArray<GCMemoryManager*> ParallelScavengeHeap::memory_managers() { 713 GrowableArray<GCMemoryManager*> memory_managers(2); 714 memory_managers.append(_young_manager); 715 memory_managers.append(_old_manager); 716 return memory_managers; 717 } 718 719 GrowableArray<MemoryPool*> ParallelScavengeHeap::memory_pools() { 720 GrowableArray<MemoryPool*> memory_pools(3); 721 memory_pools.append(_eden_pool); 722 memory_pools.append(_survivor_pool); 723 memory_pools.append(_old_pool); 724 return memory_pools; 725 }