1 /* 2 * Copyright (c) 2001, 2015, 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 "gc_implementation/parallelScavenge/adjoiningGenerations.hpp" 27 #include "gc_implementation/parallelScavenge/adjoiningVirtualSpaces.hpp" 28 #include "gc_implementation/parallelScavenge/cardTableExtension.hpp" 29 #include "gc_implementation/parallelScavenge/gcTaskManager.hpp" 30 #include "gc_implementation/parallelScavenge/generationSizer.hpp" 31 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.inline.hpp" 32 #include "gc_implementation/parallelScavenge/psAdaptiveSizePolicy.hpp" 33 #include "gc_implementation/parallelScavenge/psMarkSweep.hpp" 34 #include "gc_implementation/parallelScavenge/psParallelCompact.hpp" 35 #include "gc_implementation/parallelScavenge/psPromotionManager.hpp" 36 #include "gc_implementation/parallelScavenge/psScavenge.hpp" 37 #include "gc_implementation/parallelScavenge/vmPSOperations.hpp" 38 #include "gc_implementation/shared/gcHeapSummary.hpp" 39 #include "gc_implementation/shared/gcWhen.hpp" 40 #include "memory/gcLocker.inline.hpp" 41 #include "oops/oop.inline.hpp" 42 #include "runtime/handles.inline.hpp" 43 #include "runtime/java.hpp" 44 #include "runtime/vmThread.hpp" 45 #include "services/memTracker.hpp" 46 #include "utilities/vmError.hpp" 47 48 PSYoungGen* ParallelScavengeHeap::_young_gen = NULL; 49 PSOldGen* ParallelScavengeHeap::_old_gen = NULL; 50 PSAdaptiveSizePolicy* ParallelScavengeHeap::_size_policy = NULL; 51 PSGCAdaptivePolicyCounters* ParallelScavengeHeap::_gc_policy_counters = NULL; 52 ParallelScavengeHeap* ParallelScavengeHeap::_psh = NULL; 53 GCTaskManager* ParallelScavengeHeap::_gc_task_manager = NULL; 54 55 jint ParallelScavengeHeap::initialize() { 56 CollectedHeap::pre_initialize(); 57 58 // Initialize collector policy 59 _collector_policy = new GenerationSizer(); 60 _collector_policy->initialize_all(); 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 MemTracker::record_virtual_memory_type((address)heap_rs.base(), mtJavaHeap); 66 67 os::trace_page_sizes("ps main", _collector_policy->min_heap_byte_size(), 68 heap_size, generation_alignment(), 69 heap_rs.base(), 70 heap_rs.size()); 71 if (!heap_rs.is_reserved()) { 72 vm_shutdown_during_initialization( 73 "Could not reserve enough space for object heap"); 74 return JNI_ENOMEM; 75 } 76 77 initialize_reserved_region((HeapWord*)heap_rs.base(), (HeapWord*)(heap_rs.base() + heap_rs.size())); 78 79 CardTableExtension* const barrier_set = new CardTableExtension(reserved_region()); 80 barrier_set->initialize(); 81 set_barrier_set(barrier_set); 82 83 // Make up the generations 84 // Calculate the maximum size that a generation can grow. This 85 // includes growth into the other generation. Note that the 86 // parameter _max_gen_size is kept as the maximum 87 // size of the generation as the boundaries currently stand. 88 // _max_gen_size is still used as that value. 89 double max_gc_pause_sec = ((double) MaxGCPauseMillis)/1000.0; 90 double max_gc_minor_pause_sec = ((double) MaxGCMinorPauseMillis)/1000.0; 91 92 _psh = this; 93 _gens = new AdjoiningGenerations(heap_rs, _collector_policy, generation_alignment()); 94 95 _old_gen = _gens->old_gen(); 96 _young_gen = _gens->young_gen(); 97 98 const size_t eden_capacity = _young_gen->eden_space()->capacity_in_bytes(); 99 const size_t old_capacity = _old_gen->capacity_in_bytes(); 100 const size_t initial_promo_size = MIN2(eden_capacity, old_capacity); 101 _size_policy = 102 new PSAdaptiveSizePolicy(eden_capacity, 103 initial_promo_size, 104 young_gen()->to_space()->capacity_in_bytes(), 105 _collector_policy->gen_alignment(), 106 max_gc_pause_sec, 107 max_gc_minor_pause_sec, 108 GCTimeRatio 109 ); 110 111 assert(!UseAdaptiveGCBoundary || 112 (old_gen()->virtual_space()->high_boundary() == 113 young_gen()->virtual_space()->low_boundary()), 114 "Boundaries must meet"); 115 // initialize the policy counters - 2 collectors, 3 generations 116 _gc_policy_counters = 117 new PSGCAdaptivePolicyCounters("ParScav:MSC", 2, 3, _size_policy); 118 119 // Set up the GCTaskManager 120 _gc_task_manager = GCTaskManager::create(ParallelGCThreads); 121 122 if (UseParallelOldGC && !PSParallelCompact::initialize()) { 123 return JNI_ENOMEM; 124 } 125 126 return JNI_OK; 127 } 128 129 void ParallelScavengeHeap::post_initialize() { 130 // Need to init the tenuring threshold 131 PSScavenge::initialize(); 132 if (UseParallelOldGC) { 133 PSParallelCompact::post_initialize(); 134 } else { 135 PSMarkSweep::initialize(); 136 } 137 PSPromotionManager::initialize(); 138 } 139 140 void ParallelScavengeHeap::update_counters() { 141 young_gen()->update_counters(); 142 old_gen()->update_counters(); 143 MetaspaceCounters::update_performance_counters(); 144 CompressedClassSpaceCounters::update_performance_counters(); 145 } 146 147 size_t ParallelScavengeHeap::capacity() const { 148 size_t value = young_gen()->capacity_in_bytes() + old_gen()->capacity_in_bytes(); 149 return value; 150 } 151 152 size_t ParallelScavengeHeap::used() const { 153 size_t value = young_gen()->used_in_bytes() + old_gen()->used_in_bytes(); 154 return value; 155 } 156 157 bool ParallelScavengeHeap::is_maximal_no_gc() const { 158 return old_gen()->is_maximal_no_gc() && young_gen()->is_maximal_no_gc(); 159 } 160 161 162 size_t ParallelScavengeHeap::max_capacity() const { 163 size_t estimated = reserved_region().byte_size(); 164 if (UseAdaptiveSizePolicy) { 165 estimated -= _size_policy->max_survivor_size(young_gen()->max_size()); 166 } else { 167 estimated -= young_gen()->to_space()->capacity_in_bytes(); 168 } 169 return MAX2(estimated, capacity()); 170 } 171 172 bool ParallelScavengeHeap::is_in(const void* p) const { 173 if (young_gen()->is_in(p)) { 174 return true; 175 } 176 177 if (old_gen()->is_in(p)) { 178 return true; 179 } 180 181 return false; 182 } 183 184 bool ParallelScavengeHeap::is_in_reserved(const void* p) const { 185 if (young_gen()->is_in_reserved(p)) { 186 return true; 187 } 188 189 if (old_gen()->is_in_reserved(p)) { 190 return true; 191 } 192 193 return false; 194 } 195 196 bool ParallelScavengeHeap::is_scavengable(const void* addr) { 197 return is_in_young((oop)addr); 198 } 199 200 // There are two levels of allocation policy here. 201 // 202 // When an allocation request fails, the requesting thread must invoke a VM 203 // operation, transfer control to the VM thread, and await the results of a 204 // garbage collection. That is quite expensive, and we should avoid doing it 205 // multiple times if possible. 206 // 207 // To accomplish this, we have a basic allocation policy, and also a 208 // failed allocation policy. 209 // 210 // The basic allocation policy controls how you allocate memory without 211 // attempting garbage collection. It is okay to grab locks and 212 // expand the heap, if that can be done without coming to a safepoint. 213 // It is likely that the basic allocation policy will not be very 214 // aggressive. 215 // 216 // The failed allocation policy is invoked from the VM thread after 217 // the basic allocation policy is unable to satisfy a mem_allocate 218 // request. This policy needs to cover the entire range of collection, 219 // heap expansion, and out-of-memory conditions. It should make every 220 // attempt to allocate the requested memory. 221 222 // Basic allocation policy. Should never be called at a safepoint, or 223 // from the VM thread. 224 // 225 // This method must handle cases where many mem_allocate requests fail 226 // simultaneously. When that happens, only one VM operation will succeed, 227 // and the rest will not be executed. For that reason, this method loops 228 // during failed allocation attempts. If the java heap becomes exhausted, 229 // we rely on the size_policy object to force a bail out. 230 HeapWord* ParallelScavengeHeap::mem_allocate( 231 size_t size, 232 bool* gc_overhead_limit_was_exceeded) { 233 assert(!SafepointSynchronize::is_at_safepoint(), "should not be at safepoint"); 234 assert(Thread::current() != (Thread*)VMThread::vm_thread(), "should not be in vm thread"); 235 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); 236 237 // In general gc_overhead_limit_was_exceeded should be false so 238 // set it so here and reset it to true only if the gc time 239 // limit is being exceeded as checked below. 240 *gc_overhead_limit_was_exceeded = false; 241 242 HeapWord* result = young_gen()->allocate(size); 243 244 uint loop_count = 0; 245 uint gc_count = 0; 246 uint gclocker_stalled_count = 0; 247 248 while (result == NULL) { 249 // We don't want to have multiple collections for a single filled generation. 250 // To prevent this, each thread tracks the total_collections() value, and if 251 // the count has changed, does not do a new collection. 252 // 253 // The collection count must be read only while holding the heap lock. VM 254 // operations also hold the heap lock during collections. There is a lock 255 // contention case where thread A blocks waiting on the Heap_lock, while 256 // thread B is holding it doing a collection. When thread A gets the lock, 257 // the collection count has already changed. To prevent duplicate collections, 258 // The policy MUST attempt allocations during the same period it reads the 259 // total_collections() value! 260 { 261 MutexLocker ml(Heap_lock); 262 gc_count = total_collections(); 263 264 result = young_gen()->allocate(size); 265 if (result != NULL) { 266 return result; 267 } 268 269 // If certain conditions hold, try allocating from the old gen. 270 result = mem_allocate_old_gen(size); 271 if (result != NULL) { 272 return result; 273 } 274 275 if (gclocker_stalled_count > GCLockerRetryAllocationCount) { 276 return NULL; 277 } 278 279 // Failed to allocate without a gc. 280 if (GC_locker::is_active_and_needs_gc()) { 281 // If this thread is not in a jni critical section, we stall 282 // the requestor until the critical section has cleared and 283 // GC allowed. When the critical section clears, a GC is 284 // initiated by the last thread exiting the critical section; so 285 // we retry the allocation sequence from the beginning of the loop, 286 // rather than causing more, now probably unnecessary, GC attempts. 287 JavaThread* jthr = JavaThread::current(); 288 if (!jthr->in_critical()) { 289 MutexUnlocker mul(Heap_lock); 290 GC_locker::stall_until_clear(); 291 gclocker_stalled_count += 1; 292 continue; 293 } else { 294 if (CheckJNICalls) { 295 fatal("Possible deadlock due to allocating while" 296 " in jni critical section"); 297 } 298 return NULL; 299 } 300 } 301 } 302 303 if (result == NULL) { 304 // Generate a VM operation 305 VM_ParallelGCFailedAllocation op(size, gc_count); 306 VMThread::execute(&op); 307 308 // Did the VM operation execute? If so, return the result directly. 309 // This prevents us from looping until time out on requests that can 310 // not be satisfied. 311 if (op.prologue_succeeded()) { 312 assert(is_in_or_null(op.result()), "result not in heap"); 313 314 // If GC was locked out during VM operation then retry allocation 315 // and/or stall as necessary. 316 if (op.gc_locked()) { 317 assert(op.result() == NULL, "must be NULL if gc_locked() is true"); 318 continue; // retry and/or stall as necessary 319 } 320 321 // Exit the loop if the gc time limit has been exceeded. 322 // The allocation must have failed above ("result" guarding 323 // this path is NULL) and the most recent collection has exceeded the 324 // gc overhead limit (although enough may have been collected to 325 // satisfy the allocation). Exit the loop so that an out-of-memory 326 // will be thrown (return a NULL ignoring the contents of 327 // op.result()), 328 // but clear gc_overhead_limit_exceeded so that the next collection 329 // starts with a clean slate (i.e., forgets about previous overhead 330 // excesses). Fill op.result() with a filler object so that the 331 // heap remains parsable. 332 const bool limit_exceeded = size_policy()->gc_overhead_limit_exceeded(); 333 const bool softrefs_clear = collector_policy()->all_soft_refs_clear(); 334 335 if (limit_exceeded && softrefs_clear) { 336 *gc_overhead_limit_was_exceeded = true; 337 size_policy()->set_gc_overhead_limit_exceeded(false); 338 if (PrintGCDetails && Verbose) { 339 gclog_or_tty->print_cr("ParallelScavengeHeap::mem_allocate: " 340 "return NULL because gc_overhead_limit_exceeded is set"); 341 } 342 if (op.result() != NULL) { 343 CollectedHeap::fill_with_object(op.result(), size); 344 } 345 return NULL; 346 } 347 348 return op.result(); 349 } 350 } 351 352 // The policy object will prevent us from looping forever. If the 353 // time spent in gc crosses a threshold, we will bail out. 354 loop_count++; 355 if ((result == NULL) && (QueuedAllocationWarningCount > 0) && 356 (loop_count % QueuedAllocationWarningCount == 0)) { 357 warning("ParallelScavengeHeap::mem_allocate retries %d times \n\t" 358 " size=" SIZE_FORMAT, loop_count, size); 359 } 360 } 361 362 return result; 363 } 364 365 // A "death march" is a series of ultra-slow allocations in which a full gc is 366 // done before each allocation, and after the full gc the allocation still 367 // cannot be satisfied from the young gen. This routine detects that condition; 368 // it should be called after a full gc has been done and the allocation 369 // attempted from the young gen. The parameter 'addr' should be the result of 370 // that young gen allocation attempt. 371 void 372 ParallelScavengeHeap::death_march_check(HeapWord* const addr, size_t size) { 373 if (addr != NULL) { 374 _death_march_count = 0; // death march has ended 375 } else if (_death_march_count == 0) { 376 if (should_alloc_in_eden(size)) { 377 _death_march_count = 1; // death march has started 378 } 379 } 380 } 381 382 HeapWord* ParallelScavengeHeap::mem_allocate_old_gen(size_t size) { 383 if (!should_alloc_in_eden(size) || GC_locker::is_active_and_needs_gc()) { 384 // Size is too big for eden, or gc is locked out. 385 return old_gen()->allocate(size); 386 } 387 388 // If a "death march" is in progress, allocate from the old gen a limited 389 // number of times before doing a GC. 390 if (_death_march_count > 0) { 391 if (_death_march_count < 64) { 392 ++_death_march_count; 393 return old_gen()->allocate(size); 394 } else { 395 _death_march_count = 0; 396 } 397 } 398 return NULL; 399 } 400 401 void ParallelScavengeHeap::do_full_collection(bool clear_all_soft_refs) { 402 if (UseParallelOldGC) { 403 // The do_full_collection() parameter clear_all_soft_refs 404 // is interpreted here as maximum_compaction which will 405 // cause SoftRefs to be cleared. 406 bool maximum_compaction = clear_all_soft_refs; 407 PSParallelCompact::invoke(maximum_compaction); 408 } else { 409 PSMarkSweep::invoke(clear_all_soft_refs); 410 } 411 } 412 413 // Failed allocation policy. Must be called from the VM thread, and 414 // only at a safepoint! Note that this method has policy for allocation 415 // flow, and NOT collection policy. So we do not check for gc collection 416 // time over limit here, that is the responsibility of the heap specific 417 // collection methods. This method decides where to attempt allocations, 418 // and when to attempt collections, but no collection specific policy. 419 HeapWord* ParallelScavengeHeap::failed_mem_allocate(size_t size) { 420 assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); 421 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); 422 assert(!is_gc_active(), "not reentrant"); 423 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); 424 425 // We assume that allocation in eden will fail unless we collect. 426 427 // First level allocation failure, scavenge and allocate in young gen. 428 GCCauseSetter gccs(this, GCCause::_allocation_failure); 429 const bool invoked_full_gc = PSScavenge::invoke(); 430 HeapWord* result = young_gen()->allocate(size); 431 432 // Second level allocation failure. 433 // Mark sweep and allocate in young generation. 434 if (result == NULL && !invoked_full_gc) { 435 do_full_collection(false); 436 result = young_gen()->allocate(size); 437 } 438 439 death_march_check(result, size); 440 441 // Third level allocation failure. 442 // After mark sweep and young generation allocation failure, 443 // allocate in old generation. 444 if (result == NULL) { 445 result = old_gen()->allocate(size); 446 } 447 448 // Fourth level allocation failure. We're running out of memory. 449 // More complete mark sweep and allocate in young generation. 450 if (result == NULL) { 451 do_full_collection(true); 452 result = young_gen()->allocate(size); 453 } 454 455 // Fifth level allocation failure. 456 // After more complete mark sweep, allocate in old generation. 457 if (result == NULL) { 458 result = old_gen()->allocate(size); 459 } 460 461 return result; 462 } 463 464 void ParallelScavengeHeap::ensure_parsability(bool retire_tlabs) { 465 CollectedHeap::ensure_parsability(retire_tlabs); 466 young_gen()->eden_space()->ensure_parsability(); 467 } 468 469 size_t ParallelScavengeHeap::tlab_capacity(Thread* thr) const { 470 return young_gen()->eden_space()->tlab_capacity(thr); 471 } 472 473 size_t ParallelScavengeHeap::tlab_used(Thread* thr) const { 474 return young_gen()->eden_space()->tlab_used(thr); 475 } 476 477 size_t ParallelScavengeHeap::unsafe_max_tlab_alloc(Thread* thr) const { 478 return young_gen()->eden_space()->unsafe_max_tlab_alloc(thr); 479 } 480 481 HeapWord* ParallelScavengeHeap::allocate_new_tlab(size_t size) { 482 return young_gen()->allocate(size); 483 } 484 485 void ParallelScavengeHeap::accumulate_statistics_all_tlabs() { 486 CollectedHeap::accumulate_statistics_all_tlabs(); 487 } 488 489 void ParallelScavengeHeap::resize_all_tlabs() { 490 CollectedHeap::resize_all_tlabs(); 491 } 492 493 bool ParallelScavengeHeap::can_elide_initializing_store_barrier(oop new_obj) { 494 // We don't need barriers for stores to objects in the 495 // young gen and, a fortiori, for initializing stores to 496 // objects therein. 497 return is_in_young(new_obj); 498 } 499 500 // This method is used by System.gc() and JVMTI. 501 void ParallelScavengeHeap::collect(GCCause::Cause cause) { 502 assert(!Heap_lock->owned_by_self(), 503 "this thread should not own the Heap_lock"); 504 505 uint gc_count = 0; 506 uint full_gc_count = 0; 507 { 508 MutexLocker ml(Heap_lock); 509 // This value is guarded by the Heap_lock 510 gc_count = total_collections(); 511 full_gc_count = total_full_collections(); 512 } 513 514 VM_ParallelGCSystemGC op(gc_count, full_gc_count, cause); 515 VMThread::execute(&op); 516 } 517 518 void ParallelScavengeHeap::object_iterate(ObjectClosure* cl) { 519 young_gen()->object_iterate(cl); 520 old_gen()->object_iterate(cl); 521 } 522 523 524 HeapWord* ParallelScavengeHeap::block_start(const void* addr) const { 525 if (young_gen()->is_in_reserved(addr)) { 526 assert(young_gen()->is_in(addr), 527 "addr should be in allocated part of young gen"); 528 // called from os::print_location by find or VMError 529 if (Debugging || VMError::fatal_error_in_progress()) return NULL; 530 Unimplemented(); 531 } else if (old_gen()->is_in_reserved(addr)) { 532 assert(old_gen()->is_in(addr), 533 "addr should be in allocated part of old gen"); 534 return old_gen()->start_array()->object_start((HeapWord*)addr); 535 } 536 return 0; 537 } 538 539 size_t ParallelScavengeHeap::block_size(const HeapWord* addr) const { 540 return oop(addr)->size(); 541 } 542 543 bool ParallelScavengeHeap::block_is_obj(const HeapWord* addr) const { 544 return block_start(addr) == addr; 545 } 546 547 jlong ParallelScavengeHeap::millis_since_last_gc() { 548 return UseParallelOldGC ? 549 PSParallelCompact::millis_since_last_gc() : 550 PSMarkSweep::millis_since_last_gc(); 551 } 552 553 void ParallelScavengeHeap::prepare_for_verify() { 554 ensure_parsability(false); // no need to retire TLABs for verification 555 } 556 557 PSHeapSummary ParallelScavengeHeap::create_ps_heap_summary() { 558 PSOldGen* old = old_gen(); 559 HeapWord* old_committed_end = (HeapWord*)old->virtual_space()->committed_high_addr(); 560 VirtualSpaceSummary old_summary(old->reserved().start(), old_committed_end, old->reserved().end()); 561 SpaceSummary old_space(old->reserved().start(), old_committed_end, old->used_in_bytes()); 562 563 PSYoungGen* young = young_gen(); 564 VirtualSpaceSummary young_summary(young->reserved().start(), 565 (HeapWord*)young->virtual_space()->committed_high_addr(), young->reserved().end()); 566 567 MutableSpace* eden = young_gen()->eden_space(); 568 SpaceSummary eden_space(eden->bottom(), eden->end(), eden->used_in_bytes()); 569 570 MutableSpace* from = young_gen()->from_space(); 571 SpaceSummary from_space(from->bottom(), from->end(), from->used_in_bytes()); 572 573 MutableSpace* to = young_gen()->to_space(); 574 SpaceSummary to_space(to->bottom(), to->end(), to->used_in_bytes()); 575 576 VirtualSpaceSummary heap_summary = create_heap_space_summary(); 577 return PSHeapSummary(heap_summary, used(), old_summary, old_space, young_summary, eden_space, from_space, to_space); 578 } 579 580 void ParallelScavengeHeap::print_on(outputStream* st) const { 581 young_gen()->print_on(st); 582 old_gen()->print_on(st); 583 MetaspaceAux::print_on(st); 584 } 585 586 void ParallelScavengeHeap::print_on_error(outputStream* st) const { 587 this->CollectedHeap::print_on_error(st); 588 589 if (UseParallelOldGC) { 590 st->cr(); 591 PSParallelCompact::print_on_error(st); 592 } 593 } 594 595 void ParallelScavengeHeap::gc_threads_do(ThreadClosure* tc) const { 596 PSScavenge::gc_task_manager()->threads_do(tc); 597 } 598 599 void ParallelScavengeHeap::print_gc_threads_on(outputStream* st) const { 600 PSScavenge::gc_task_manager()->print_threads_on(st); 601 } 602 603 void ParallelScavengeHeap::print_tracing_info() const { 604 if (TraceYoungGenTime) { 605 double time = PSScavenge::accumulated_time()->seconds(); 606 tty->print_cr("[Accumulated GC generation 0 time %3.7f secs]", time); 607 } 608 if (TraceOldGenTime) { 609 double time = UseParallelOldGC ? PSParallelCompact::accumulated_time()->seconds() : PSMarkSweep::accumulated_time()->seconds(); 610 tty->print_cr("[Accumulated GC generation 1 time %3.7f secs]", time); 611 } 612 } 613 614 615 void ParallelScavengeHeap::verify(bool silent, VerifyOption option /* ignored */) { 616 // Why do we need the total_collections()-filter below? 617 if (total_collections() > 0) { 618 if (!silent) { 619 gclog_or_tty->print("tenured "); 620 } 621 old_gen()->verify(); 622 623 if (!silent) { 624 gclog_or_tty->print("eden "); 625 } 626 young_gen()->verify(); 627 } 628 } 629 630 void ParallelScavengeHeap::print_heap_change(size_t prev_used) { 631 if (PrintGCDetails && Verbose) { 632 gclog_or_tty->print(" " SIZE_FORMAT 633 "->" SIZE_FORMAT 634 "(" SIZE_FORMAT ")", 635 prev_used, used(), capacity()); 636 } else { 637 gclog_or_tty->print(" " SIZE_FORMAT "K" 638 "->" SIZE_FORMAT "K" 639 "(" SIZE_FORMAT "K)", 640 prev_used / K, used() / K, capacity() / K); 641 } 642 } 643 644 void ParallelScavengeHeap::trace_heap(GCWhen::Type when, const GCTracer* gc_tracer) { 645 const PSHeapSummary& heap_summary = create_ps_heap_summary(); 646 gc_tracer->report_gc_heap_summary(when, heap_summary); 647 648 const MetaspaceSummary& metaspace_summary = create_metaspace_summary(); 649 gc_tracer->report_metaspace_summary(when, metaspace_summary); 650 } 651 652 ParallelScavengeHeap* ParallelScavengeHeap::heap() { 653 assert(_psh != NULL, "Uninitialized access to ParallelScavengeHeap::heap()"); 654 assert(_psh->kind() == CollectedHeap::ParallelScavengeHeap, "not a parallel scavenge heap"); 655 return _psh; 656 } 657 658 // Before delegating the resize to the young generation, 659 // the reserved space for the young and old generations 660 // may be changed to accommodate the desired resize. 661 void ParallelScavengeHeap::resize_young_gen(size_t eden_size, 662 size_t survivor_size) { 663 if (UseAdaptiveGCBoundary) { 664 if (size_policy()->bytes_absorbed_from_eden() != 0) { 665 size_policy()->reset_bytes_absorbed_from_eden(); 666 return; // The generation changed size already. 667 } 668 gens()->adjust_boundary_for_young_gen_needs(eden_size, survivor_size); 669 } 670 671 // Delegate the resize to the generation. 672 _young_gen->resize(eden_size, survivor_size); 673 } 674 675 // Before delegating the resize to the old generation, 676 // the reserved space for the young and old generations 677 // may be changed to accommodate the desired resize. 678 void ParallelScavengeHeap::resize_old_gen(size_t desired_free_space) { 679 if (UseAdaptiveGCBoundary) { 680 if (size_policy()->bytes_absorbed_from_eden() != 0) { 681 size_policy()->reset_bytes_absorbed_from_eden(); 682 return; // The generation changed size already. 683 } 684 gens()->adjust_boundary_for_old_gen_needs(desired_free_space); 685 } 686 687 // Delegate the resize to the generation. 688 _old_gen->resize(desired_free_space); 689 } 690 691 ParallelScavengeHeap::ParStrongRootsScope::ParStrongRootsScope() { 692 // nothing particular 693 } 694 695 ParallelScavengeHeap::ParStrongRootsScope::~ParStrongRootsScope() { 696 // nothing particular 697 } 698 699 #ifndef PRODUCT 700 void ParallelScavengeHeap::record_gen_tops_before_GC() { 701 if (ZapUnusedHeapArea) { 702 young_gen()->record_spaces_top(); 703 old_gen()->record_spaces_top(); 704 } 705 } 706 707 void ParallelScavengeHeap::gen_mangle_unused_area() { 708 if (ZapUnusedHeapArea) { 709 young_gen()->eden_space()->mangle_unused_area(); 710 young_gen()->to_space()->mangle_unused_area(); 711 young_gen()->from_space()->mangle_unused_area(); 712 old_gen()->object_space()->mangle_unused_area(); 713 } 714 } 715 #endif