1 /* 2 * Copyright (c) 2001, 2017, 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/cardTableExtension.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/psMarkSweep.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/vmPSOperations.hpp" 41 #include "gc/shared/gcHeapSummary.hpp" 42 #include "gc/shared/gcLocker.inline.hpp" 43 #include "gc/shared/gcWhen.hpp" 44 #include "logging/log.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 CollectedHeap::pre_initialize(); 61 62 const size_t heap_size = _collector_policy->max_heap_byte_size(); 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 CardTableExtension* const barrier_set = new CardTableExtension(reserved_region()); 76 barrier_set->initialize(); 77 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 } 120 121 122 _eden_pool = new EdenMutableSpacePool(_young_gen, 123 _young_gen->eden_space(), 124 "PS Eden Space", 125 false /* support_usage_threshold */); 126 127 _survivor_pool = new SurvivorMutableSpacePool(_young_gen, 128 "PS Survivor Space", 129 false /* support_usage_threshold */); 130 131 _old_pool = new PSGenerationPool(_old_gen, 132 "PS Old Gen", 133 true /* support_usage_threshold */); 134 135 _young_manager = new GCMemoryManager("PS Scavenge", "end of minor GC"); 136 _old_manager = new GCMemoryManager("PS MarkSweep", "end of major GC"); 137 138 _old_manager->add_pool(_eden_pool); 139 _old_manager->add_pool(_survivor_pool); 140 _old_manager->add_pool(_old_pool); 141 142 _young_manager->add_pool(_eden_pool); 143 _young_manager->add_pool(_survivor_pool); 144 145 return JNI_OK; 146 } 147 148 void ParallelScavengeHeap::post_initialize() { 149 // Need to init the tenuring threshold 150 PSScavenge::initialize(); 151 if (UseParallelOldGC) { 152 PSParallelCompact::post_initialize(); 153 } else { 154 PSMarkSweep::initialize(); 155 } 156 PSPromotionManager::initialize(); 157 } 158 159 void ParallelScavengeHeap::update_counters() { 160 young_gen()->update_counters(); 161 old_gen()->update_counters(); 162 MetaspaceCounters::update_performance_counters(); 163 CompressedClassSpaceCounters::update_performance_counters(); 164 } 165 166 size_t ParallelScavengeHeap::capacity() const { 167 size_t value = young_gen()->capacity_in_bytes() + old_gen()->capacity_in_bytes(); 168 return value; 169 } 170 171 size_t ParallelScavengeHeap::used() const { 172 size_t value = young_gen()->used_in_bytes() + old_gen()->used_in_bytes(); 173 return value; 174 } 175 176 bool ParallelScavengeHeap::is_maximal_no_gc() const { 177 return old_gen()->is_maximal_no_gc() && young_gen()->is_maximal_no_gc(); 178 } 179 180 181 size_t ParallelScavengeHeap::max_capacity() const { 182 size_t estimated = reserved_region().byte_size(); 183 if (UseAdaptiveSizePolicy) { 184 estimated -= _size_policy->max_survivor_size(young_gen()->max_size()); 185 } else { 186 estimated -= young_gen()->to_space()->capacity_in_bytes(); 187 } 188 return MAX2(estimated, capacity()); 189 } 190 191 bool ParallelScavengeHeap::is_in(const void* p) const { 192 return young_gen()->is_in(p) || old_gen()->is_in(p); 193 } 194 195 bool ParallelScavengeHeap::is_in_reserved(const void* p) const { 196 return young_gen()->is_in_reserved(p) || old_gen()->is_in_reserved(p); 197 } 198 199 // There are two levels of allocation policy here. 200 // 201 // When an allocation request fails, the requesting thread must invoke a VM 202 // operation, transfer control to the VM thread, and await the results of a 203 // garbage collection. That is quite expensive, and we should avoid doing it 204 // multiple times if possible. 205 // 206 // To accomplish this, we have a basic allocation policy, and also a 207 // failed allocation policy. 208 // 209 // The basic allocation policy controls how you allocate memory without 210 // attempting garbage collection. It is okay to grab locks and 211 // expand the heap, if that can be done without coming to a safepoint. 212 // It is likely that the basic allocation policy will not be very 213 // aggressive. 214 // 215 // The failed allocation policy is invoked from the VM thread after 216 // the basic allocation policy is unable to satisfy a mem_allocate 217 // request. This policy needs to cover the entire range of collection, 218 // heap expansion, and out-of-memory conditions. It should make every 219 // attempt to allocate the requested memory. 220 221 // Basic allocation policy. Should never be called at a safepoint, or 222 // from the VM thread. 223 // 224 // This method must handle cases where many mem_allocate requests fail 225 // simultaneously. When that happens, only one VM operation will succeed, 226 // and the rest will not be executed. For that reason, this method loops 227 // during failed allocation attempts. If the java heap becomes exhausted, 228 // we rely on the size_policy object to force a bail out. 229 HeapWord* ParallelScavengeHeap::mem_allocate( 230 size_t size, 231 bool* gc_overhead_limit_was_exceeded) { 232 assert(!SafepointSynchronize::is_at_safepoint(), "should not be at safepoint"); 233 assert(Thread::current() != (Thread*)VMThread::vm_thread(), "should not be in vm thread"); 234 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); 235 236 // In general gc_overhead_limit_was_exceeded should be false so 237 // set it so here and reset it to true only if the gc time 238 // limit is being exceeded as checked below. 239 *gc_overhead_limit_was_exceeded = false; 240 241 HeapWord* result = young_gen()->allocate(size); 242 243 uint loop_count = 0; 244 uint gc_count = 0; 245 uint gclocker_stalled_count = 0; 246 247 while (result == NULL) { 248 // We don't want to have multiple collections for a single filled generation. 249 // To prevent this, each thread tracks the total_collections() value, and if 250 // the count has changed, does not do a new collection. 251 // 252 // The collection count must be read only while holding the heap lock. VM 253 // operations also hold the heap lock during collections. There is a lock 254 // contention case where thread A blocks waiting on the Heap_lock, while 255 // thread B is holding it doing a collection. When thread A gets the lock, 256 // the collection count has already changed. To prevent duplicate collections, 257 // The policy MUST attempt allocations during the same period it reads the 258 // total_collections() value! 259 { 260 MutexLocker ml(Heap_lock); 261 gc_count = total_collections(); 262 263 result = young_gen()->allocate(size); 264 if (result != NULL) { 265 return result; 266 } 267 268 // If certain conditions hold, try allocating from the old gen. 269 result = mem_allocate_old_gen(size); 270 if (result != NULL) { 271 return result; 272 } 273 274 if (gclocker_stalled_count > GCLockerRetryAllocationCount) { 275 return NULL; 276 } 277 278 // Failed to allocate without a gc. 279 if (GCLocker::is_active_and_needs_gc()) { 280 // If this thread is not in a jni critical section, we stall 281 // the requestor until the critical section has cleared and 282 // GC allowed. When the critical section clears, a GC is 283 // initiated by the last thread exiting the critical section; so 284 // we retry the allocation sequence from the beginning of the loop, 285 // rather than causing more, now probably unnecessary, GC attempts. 286 JavaThread* jthr = JavaThread::current(); 287 if (!jthr->in_critical()) { 288 MutexUnlocker mul(Heap_lock); 289 GCLocker::stall_until_clear(); 290 gclocker_stalled_count += 1; 291 continue; 292 } else { 293 if (CheckJNICalls) { 294 fatal("Possible deadlock due to allocating while" 295 " in jni critical section"); 296 } 297 return NULL; 298 } 299 } 300 } 301 302 if (result == NULL) { 303 // Generate a VM operation 304 VM_ParallelGCFailedAllocation op(size, gc_count); 305 VMThread::execute(&op); 306 307 // Did the VM operation execute? If so, return the result directly. 308 // This prevents us from looping until time out on requests that can 309 // not be satisfied. 310 if (op.prologue_succeeded()) { 311 assert(is_in_or_null(op.result()), "result not in heap"); 312 313 // If GC was locked out during VM operation then retry allocation 314 // and/or stall as necessary. 315 if (op.gc_locked()) { 316 assert(op.result() == NULL, "must be NULL if gc_locked() is true"); 317 continue; // retry and/or stall as necessary 318 } 319 320 // Exit the loop if the gc time limit has been exceeded. 321 // The allocation must have failed above ("result" guarding 322 // this path is NULL) and the most recent collection has exceeded the 323 // gc overhead limit (although enough may have been collected to 324 // satisfy the allocation). Exit the loop so that an out-of-memory 325 // will be thrown (return a NULL ignoring the contents of 326 // op.result()), 327 // but clear gc_overhead_limit_exceeded so that the next collection 328 // starts with a clean slate (i.e., forgets about previous overhead 329 // excesses). Fill op.result() with a filler object so that the 330 // heap remains parsable. 331 const bool limit_exceeded = size_policy()->gc_overhead_limit_exceeded(); 332 const bool softrefs_clear = collector_policy()->all_soft_refs_clear(); 333 334 if (limit_exceeded && softrefs_clear) { 335 *gc_overhead_limit_was_exceeded = true; 336 size_policy()->set_gc_overhead_limit_exceeded(false); 337 log_trace(gc)("ParallelScavengeHeap::mem_allocate: return NULL because gc_overhead_limit_exceeded is set"); 338 if (op.result() != NULL) { 339 CollectedHeap::fill_with_object(op.result(), size); 340 } 341 return NULL; 342 } 343 344 return op.result(); 345 } 346 } 347 348 // The policy object will prevent us from looping forever. If the 349 // time spent in gc crosses a threshold, we will bail out. 350 loop_count++; 351 if ((result == NULL) && (QueuedAllocationWarningCount > 0) && 352 (loop_count % QueuedAllocationWarningCount == 0)) { 353 log_warning(gc)("ParallelScavengeHeap::mem_allocate retries %d times", loop_count); 354 log_warning(gc)("\tsize=" SIZE_FORMAT, size); 355 } 356 } 357 358 return result; 359 } 360 361 // A "death march" is a series of ultra-slow allocations in which a full gc is 362 // done before each allocation, and after the full gc the allocation still 363 // cannot be satisfied from the young gen. This routine detects that condition; 364 // it should be called after a full gc has been done and the allocation 365 // attempted from the young gen. The parameter 'addr' should be the result of 366 // that young gen allocation attempt. 367 void 368 ParallelScavengeHeap::death_march_check(HeapWord* const addr, size_t size) { 369 if (addr != NULL) { 370 _death_march_count = 0; // death march has ended 371 } else if (_death_march_count == 0) { 372 if (should_alloc_in_eden(size)) { 373 _death_march_count = 1; // death march has started 374 } 375 } 376 } 377 378 HeapWord* ParallelScavengeHeap::mem_allocate_old_gen(size_t size) { 379 if (!should_alloc_in_eden(size) || GCLocker::is_active_and_needs_gc()) { 380 // Size is too big for eden, or gc is locked out. 381 return old_gen()->allocate(size); 382 } 383 384 // If a "death march" is in progress, allocate from the old gen a limited 385 // number of times before doing a GC. 386 if (_death_march_count > 0) { 387 if (_death_march_count < 64) { 388 ++_death_march_count; 389 return old_gen()->allocate(size); 390 } else { 391 _death_march_count = 0; 392 } 393 } 394 return NULL; 395 } 396 397 void ParallelScavengeHeap::do_full_collection(bool clear_all_soft_refs) { 398 if (UseParallelOldGC) { 399 // The do_full_collection() parameter clear_all_soft_refs 400 // is interpreted here as maximum_compaction which will 401 // cause SoftRefs to be cleared. 402 bool maximum_compaction = clear_all_soft_refs; 403 PSParallelCompact::invoke(maximum_compaction); 404 } else { 405 PSMarkSweep::invoke(clear_all_soft_refs); 406 } 407 } 408 409 // Failed allocation policy. Must be called from the VM thread, and 410 // only at a safepoint! Note that this method has policy for allocation 411 // flow, and NOT collection policy. So we do not check for gc collection 412 // time over limit here, that is the responsibility of the heap specific 413 // collection methods. This method decides where to attempt allocations, 414 // and when to attempt collections, but no collection specific policy. 415 HeapWord* ParallelScavengeHeap::failed_mem_allocate(size_t size) { 416 assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); 417 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); 418 assert(!is_gc_active(), "not reentrant"); 419 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); 420 421 // We assume that allocation in eden will fail unless we collect. 422 423 // First level allocation failure, scavenge and allocate in young gen. 424 GCCauseSetter gccs(this, GCCause::_allocation_failure); 425 const bool invoked_full_gc = PSScavenge::invoke(); 426 HeapWord* result = young_gen()->allocate(size); 427 428 // Second level allocation failure. 429 // Mark sweep and allocate in young generation. 430 if (result == NULL && !invoked_full_gc) { 431 do_full_collection(false); 432 result = young_gen()->allocate(size); 433 } 434 435 death_march_check(result, size); 436 437 // Third level allocation failure. 438 // After mark sweep and young generation allocation failure, 439 // allocate in old generation. 440 if (result == NULL) { 441 result = old_gen()->allocate(size); 442 } 443 444 // Fourth level allocation failure. We're running out of memory. 445 // More complete mark sweep and allocate in young generation. 446 if (result == NULL) { 447 do_full_collection(true); 448 result = young_gen()->allocate(size); 449 } 450 451 // Fifth level allocation failure. 452 // After more complete mark sweep, allocate in old generation. 453 if (result == NULL) { 454 result = old_gen()->allocate(size); 455 } 456 457 return result; 458 } 459 460 void ParallelScavengeHeap::ensure_parsability(bool retire_tlabs) { 461 CollectedHeap::ensure_parsability(retire_tlabs); 462 young_gen()->eden_space()->ensure_parsability(); 463 } 464 465 size_t ParallelScavengeHeap::tlab_capacity(Thread* thr) const { 466 return young_gen()->eden_space()->tlab_capacity(thr); 467 } 468 469 size_t ParallelScavengeHeap::tlab_used(Thread* thr) const { 470 return young_gen()->eden_space()->tlab_used(thr); 471 } 472 473 size_t ParallelScavengeHeap::unsafe_max_tlab_alloc(Thread* thr) const { 474 return young_gen()->eden_space()->unsafe_max_tlab_alloc(thr); 475 } 476 477 HeapWord* ParallelScavengeHeap::allocate_new_tlab(size_t size) { 478 return young_gen()->allocate(size); 479 } 480 481 void ParallelScavengeHeap::accumulate_statistics_all_tlabs() { 482 CollectedHeap::accumulate_statistics_all_tlabs(); 483 } 484 485 void ParallelScavengeHeap::resize_all_tlabs() { 486 CollectedHeap::resize_all_tlabs(); 487 } 488 489 bool ParallelScavengeHeap::can_elide_initializing_store_barrier(oop new_obj) { 490 // We don't need barriers for stores to objects in the 491 // young gen and, a fortiori, for initializing stores to 492 // objects therein. 493 return is_in_young(new_obj); 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 PSMarkSweep::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 MetaspaceAux::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() : PSMarkSweep::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::ParallelScavengeHeap, "Not a ParallelScavengeHeap"); 630 return (ParallelScavengeHeap*)heap; 631 } 632 633 // Before delegating the resize to the young generation, 634 // the reserved space for the young and old generations 635 // may be changed to accommodate the desired resize. 636 void ParallelScavengeHeap::resize_young_gen(size_t eden_size, 637 size_t survivor_size) { 638 if (UseAdaptiveGCBoundary) { 639 if (size_policy()->bytes_absorbed_from_eden() != 0) { 640 size_policy()->reset_bytes_absorbed_from_eden(); 641 return; // The generation changed size already. 642 } 643 gens()->adjust_boundary_for_young_gen_needs(eden_size, survivor_size); 644 } 645 646 // Delegate the resize to the generation. 647 _young_gen->resize(eden_size, survivor_size); 648 } 649 650 // Before delegating the resize to the old generation, 651 // the reserved space for the young and old generations 652 // may be changed to accommodate the desired resize. 653 void ParallelScavengeHeap::resize_old_gen(size_t desired_free_space) { 654 if (UseAdaptiveGCBoundary) { 655 if (size_policy()->bytes_absorbed_from_eden() != 0) { 656 size_policy()->reset_bytes_absorbed_from_eden(); 657 return; // The generation changed size already. 658 } 659 gens()->adjust_boundary_for_old_gen_needs(desired_free_space); 660 } 661 662 // Delegate the resize to the generation. 663 _old_gen->resize(desired_free_space); 664 } 665 666 ParallelScavengeHeap::ParStrongRootsScope::ParStrongRootsScope() { 667 // nothing particular 668 } 669 670 ParallelScavengeHeap::ParStrongRootsScope::~ParStrongRootsScope() { 671 // nothing particular 672 } 673 674 #ifndef PRODUCT 675 void ParallelScavengeHeap::record_gen_tops_before_GC() { 676 if (ZapUnusedHeapArea) { 677 young_gen()->record_spaces_top(); 678 old_gen()->record_spaces_top(); 679 } 680 } 681 682 void ParallelScavengeHeap::gen_mangle_unused_area() { 683 if (ZapUnusedHeapArea) { 684 young_gen()->eden_space()->mangle_unused_area(); 685 young_gen()->to_space()->mangle_unused_area(); 686 young_gen()->from_space()->mangle_unused_area(); 687 old_gen()->object_space()->mangle_unused_area(); 688 } 689 } 690 #endif 691 692 bool ParallelScavengeHeap::is_scavengable(oop obj) { 693 return is_in_young(obj); 694 } 695 696 void ParallelScavengeHeap::register_nmethod(nmethod* nm) { 697 CodeCache::register_scavenge_root_nmethod(nm); 698 } 699 700 void ParallelScavengeHeap::verify_nmethod(nmethod* nm) { 701 CodeCache::verify_scavenge_root_nmethod(nm); 702 } 703 704 GrowableArray<GCMemoryManager*> ParallelScavengeHeap::memory_managers() { 705 GrowableArray<GCMemoryManager*> memory_managers(2); 706 memory_managers.append(_young_manager); 707 memory_managers.append(_old_manager); 708 return memory_managers; 709 } 710 711 GrowableArray<MemoryPool*> ParallelScavengeHeap::memory_pools() { 712 GrowableArray<MemoryPool*> memory_pools(3); 713 memory_pools.append(_eden_pool); 714 memory_pools.append(_survivor_pool); 715 memory_pools.append(_old_pool); 716 return memory_pools; 717 } 718