1 /* 2 * Copyright (c) 2001, 2013, 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 _reserved = MemRegion((HeapWord*)heap_rs.base(), 78 (HeapWord*)(heap_rs.base() + heap_rs.size())); 79 80 CardTableExtension* const barrier_set = new CardTableExtension(_reserved, 3); 81 _barrier_set = barrier_set; 82 oopDesc::set_bs(_barrier_set); 83 if (_barrier_set == NULL) { 84 vm_shutdown_during_initialization( 85 "Could not reserve enough space for barrier set"); 86 return JNI_ENOMEM; 87 } 88 89 // Make up the generations 90 // Calculate the maximum size that a generation can grow. This 91 // includes growth into the other generation. Note that the 92 // parameter _max_gen_size is kept as the maximum 93 // size of the generation as the boundaries currently stand. 94 // _max_gen_size is still used as that value. 95 double max_gc_pause_sec = ((double) MaxGCPauseMillis)/1000.0; 96 double max_gc_minor_pause_sec = ((double) MaxGCMinorPauseMillis)/1000.0; 97 98 _gens = new AdjoiningGenerations(heap_rs, _collector_policy, generation_alignment()); 99 100 _old_gen = _gens->old_gen(); 101 _young_gen = _gens->young_gen(); 102 103 const size_t eden_capacity = _young_gen->eden_space()->capacity_in_bytes(); 104 const size_t old_capacity = _old_gen->capacity_in_bytes(); 105 const size_t initial_promo_size = MIN2(eden_capacity, old_capacity); 106 _size_policy = 107 new PSAdaptiveSizePolicy(eden_capacity, 108 initial_promo_size, 109 young_gen()->to_space()->capacity_in_bytes(), 110 _collector_policy->gen_alignment(), 111 max_gc_pause_sec, 112 max_gc_minor_pause_sec, 113 GCTimeRatio 114 ); 115 116 assert(!UseAdaptiveGCBoundary || 117 (old_gen()->virtual_space()->high_boundary() == 118 young_gen()->virtual_space()->low_boundary()), 119 "Boundaries must meet"); 120 // initialize the policy counters - 2 collectors, 3 generations 121 _gc_policy_counters = 122 new PSGCAdaptivePolicyCounters("ParScav:MSC", 2, 3, _size_policy); 123 _psh = this; 124 125 // Set up the GCTaskManager 126 _gc_task_manager = GCTaskManager::create(ParallelGCThreads); 127 128 if (UseParallelOldGC && !PSParallelCompact::initialize()) { 129 return JNI_ENOMEM; 130 } 131 132 return JNI_OK; 133 } 134 135 void ParallelScavengeHeap::post_initialize() { 136 // Need to init the tenuring threshold 137 PSScavenge::initialize(); 138 if (UseParallelOldGC) { 139 PSParallelCompact::post_initialize(); 140 } else { 141 PSMarkSweep::initialize(); 142 } 143 PSPromotionManager::initialize(); 144 } 145 146 void ParallelScavengeHeap::update_counters() { 147 young_gen()->update_counters(); 148 old_gen()->update_counters(); 149 MetaspaceCounters::update_performance_counters(); 150 CompressedClassSpaceCounters::update_performance_counters(); 151 } 152 153 size_t ParallelScavengeHeap::capacity() const { 154 size_t value = young_gen()->capacity_in_bytes() + old_gen()->capacity_in_bytes(); 155 return value; 156 } 157 158 size_t ParallelScavengeHeap::used() const { 159 size_t value = young_gen()->used_in_bytes() + old_gen()->used_in_bytes(); 160 return value; 161 } 162 163 bool ParallelScavengeHeap::is_maximal_no_gc() const { 164 return old_gen()->is_maximal_no_gc() && young_gen()->is_maximal_no_gc(); 165 } 166 167 168 size_t ParallelScavengeHeap::max_capacity() const { 169 size_t estimated = reserved_region().byte_size(); 170 if (UseAdaptiveSizePolicy) { 171 estimated -= _size_policy->max_survivor_size(young_gen()->max_size()); 172 } else { 173 estimated -= young_gen()->to_space()->capacity_in_bytes(); 174 } 175 return MAX2(estimated, capacity()); 176 } 177 178 bool ParallelScavengeHeap::is_in(const void* p) const { 179 if (young_gen()->is_in(p)) { 180 return true; 181 } 182 183 if (old_gen()->is_in(p)) { 184 return true; 185 } 186 187 return false; 188 } 189 190 bool ParallelScavengeHeap::is_in_reserved(const void* p) const { 191 if (young_gen()->is_in_reserved(p)) { 192 return true; 193 } 194 195 if (old_gen()->is_in_reserved(p)) { 196 return true; 197 } 198 199 return false; 200 } 201 202 bool ParallelScavengeHeap::is_scavengable(const void* addr) { 203 return is_in_young((oop)addr); 204 } 205 206 #ifdef ASSERT 207 // Don't implement this by using is_in_young(). This method is used 208 // in some cases to check that is_in_young() is correct. 209 bool ParallelScavengeHeap::is_in_partial_collection(const void *p) { 210 assert(is_in_reserved(p) || p == NULL, 211 "Does not work if address is non-null and outside of the heap"); 212 // The order of the generations is old (low addr), young (high addr) 213 return p >= old_gen()->reserved().end(); 214 } 215 #endif 216 217 // There are two levels of allocation policy here. 218 // 219 // When an allocation request fails, the requesting thread must invoke a VM 220 // operation, transfer control to the VM thread, and await the results of a 221 // garbage collection. That is quite expensive, and we should avoid doing it 222 // multiple times if possible. 223 // 224 // To accomplish this, we have a basic allocation policy, and also a 225 // failed allocation policy. 226 // 227 // The basic allocation policy controls how you allocate memory without 228 // attempting garbage collection. It is okay to grab locks and 229 // expand the heap, if that can be done without coming to a safepoint. 230 // It is likely that the basic allocation policy will not be very 231 // aggressive. 232 // 233 // The failed allocation policy is invoked from the VM thread after 234 // the basic allocation policy is unable to satisfy a mem_allocate 235 // request. This policy needs to cover the entire range of collection, 236 // heap expansion, and out-of-memory conditions. It should make every 237 // attempt to allocate the requested memory. 238 239 // Basic allocation policy. Should never be called at a safepoint, or 240 // from the VM thread. 241 // 242 // This method must handle cases where many mem_allocate requests fail 243 // simultaneously. When that happens, only one VM operation will succeed, 244 // and the rest will not be executed. For that reason, this method loops 245 // during failed allocation attempts. If the java heap becomes exhausted, 246 // we rely on the size_policy object to force a bail out. 247 HeapWord* ParallelScavengeHeap::mem_allocate( 248 size_t size, 249 bool* gc_overhead_limit_was_exceeded) { 250 assert(!SafepointSynchronize::is_at_safepoint(), "should not be at safepoint"); 251 assert(Thread::current() != (Thread*)VMThread::vm_thread(), "should not be in vm thread"); 252 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); 253 254 // In general gc_overhead_limit_was_exceeded should be false so 255 // set it so here and reset it to true only if the gc time 256 // limit is being exceeded as checked below. 257 *gc_overhead_limit_was_exceeded = false; 258 259 HeapWord* result = young_gen()->allocate(size); 260 261 uint loop_count = 0; 262 uint gc_count = 0; 263 int gclocker_stalled_count = 0; 264 265 while (result == NULL) { 266 // We don't want to have multiple collections for a single filled generation. 267 // To prevent this, each thread tracks the total_collections() value, and if 268 // the count has changed, does not do a new collection. 269 // 270 // The collection count must be read only while holding the heap lock. VM 271 // operations also hold the heap lock during collections. There is a lock 272 // contention case where thread A blocks waiting on the Heap_lock, while 273 // thread B is holding it doing a collection. When thread A gets the lock, 274 // the collection count has already changed. To prevent duplicate collections, 275 // The policy MUST attempt allocations during the same period it reads the 276 // total_collections() value! 277 { 278 MutexLocker ml(Heap_lock); 279 gc_count = Universe::heap()->total_collections(); 280 281 result = young_gen()->allocate(size); 282 if (result != NULL) { 283 return result; 284 } 285 286 // If certain conditions hold, try allocating from the old gen. 287 result = mem_allocate_old_gen(size); 288 if (result != NULL) { 289 return result; 290 } 291 292 if (gclocker_stalled_count > GCLockerRetryAllocationCount) { 293 return NULL; 294 } 295 296 // Failed to allocate without a gc. 297 if (GC_locker::is_active_and_needs_gc()) { 298 // If this thread is not in a jni critical section, we stall 299 // the requestor until the critical section has cleared and 300 // GC allowed. When the critical section clears, a GC is 301 // initiated by the last thread exiting the critical section; so 302 // we retry the allocation sequence from the beginning of the loop, 303 // rather than causing more, now probably unnecessary, GC attempts. 304 JavaThread* jthr = JavaThread::current(); 305 if (!jthr->in_critical()) { 306 MutexUnlocker mul(Heap_lock); 307 GC_locker::stall_until_clear(); 308 gclocker_stalled_count += 1; 309 continue; 310 } else { 311 if (CheckJNICalls) { 312 fatal("Possible deadlock due to allocating while" 313 " in jni critical section"); 314 } 315 return NULL; 316 } 317 } 318 } 319 320 if (result == NULL) { 321 // Generate a VM operation 322 VM_ParallelGCFailedAllocation op(size, gc_count); 323 VMThread::execute(&op); 324 325 // Did the VM operation execute? If so, return the result directly. 326 // This prevents us from looping until time out on requests that can 327 // not be satisfied. 328 if (op.prologue_succeeded()) { 329 assert(Universe::heap()->is_in_or_null(op.result()), 330 "result not in heap"); 331 332 // If GC was locked out during VM operation then retry allocation 333 // and/or stall as necessary. 334 if (op.gc_locked()) { 335 assert(op.result() == NULL, "must be NULL if gc_locked() is true"); 336 continue; // retry and/or stall as necessary 337 } 338 339 // Exit the loop if the gc time limit has been exceeded. 340 // The allocation must have failed above ("result" guarding 341 // this path is NULL) and the most recent collection has exceeded the 342 // gc overhead limit (although enough may have been collected to 343 // satisfy the allocation). Exit the loop so that an out-of-memory 344 // will be thrown (return a NULL ignoring the contents of 345 // op.result()), 346 // but clear gc_overhead_limit_exceeded so that the next collection 347 // starts with a clean slate (i.e., forgets about previous overhead 348 // excesses). Fill op.result() with a filler object so that the 349 // heap remains parsable. 350 const bool limit_exceeded = size_policy()->gc_overhead_limit_exceeded(); 351 const bool softrefs_clear = collector_policy()->all_soft_refs_clear(); 352 353 if (limit_exceeded && softrefs_clear) { 354 *gc_overhead_limit_was_exceeded = true; 355 size_policy()->set_gc_overhead_limit_exceeded(false); 356 if (PrintGCDetails && Verbose) { 357 gclog_or_tty->print_cr("ParallelScavengeHeap::mem_allocate: " 358 "return NULL because gc_overhead_limit_exceeded is set"); 359 } 360 if (op.result() != NULL) { 361 CollectedHeap::fill_with_object(op.result(), size); 362 } 363 return NULL; 364 } 365 366 return op.result(); 367 } 368 } 369 370 // The policy object will prevent us from looping forever. If the 371 // time spent in gc crosses a threshold, we will bail out. 372 loop_count++; 373 if ((result == NULL) && (QueuedAllocationWarningCount > 0) && 374 (loop_count % QueuedAllocationWarningCount == 0)) { 375 warning("ParallelScavengeHeap::mem_allocate retries %d times \n\t" 376 " size=%d", loop_count, size); 377 } 378 } 379 380 return result; 381 } 382 383 // A "death march" is a series of ultra-slow allocations in which a full gc is 384 // done before each allocation, and after the full gc the allocation still 385 // cannot be satisfied from the young gen. This routine detects that condition; 386 // it should be called after a full gc has been done and the allocation 387 // attempted from the young gen. The parameter 'addr' should be the result of 388 // that young gen allocation attempt. 389 void 390 ParallelScavengeHeap::death_march_check(HeapWord* const addr, size_t size) { 391 if (addr != NULL) { 392 _death_march_count = 0; // death march has ended 393 } else if (_death_march_count == 0) { 394 if (should_alloc_in_eden(size)) { 395 _death_march_count = 1; // death march has started 396 } 397 } 398 } 399 400 HeapWord* ParallelScavengeHeap::mem_allocate_old_gen(size_t size) { 401 if (!should_alloc_in_eden(size) || GC_locker::is_active_and_needs_gc()) { 402 // Size is too big for eden, or gc is locked out. 403 return old_gen()->allocate(size); 404 } 405 406 // If a "death march" is in progress, allocate from the old gen a limited 407 // number of times before doing a GC. 408 if (_death_march_count > 0) { 409 if (_death_march_count < 64) { 410 ++_death_march_count; 411 return old_gen()->allocate(size); 412 } else { 413 _death_march_count = 0; 414 } 415 } 416 return NULL; 417 } 418 419 void ParallelScavengeHeap::do_full_collection(bool clear_all_soft_refs) { 420 if (UseParallelOldGC) { 421 // The do_full_collection() parameter clear_all_soft_refs 422 // is interpreted here as maximum_compaction which will 423 // cause SoftRefs to be cleared. 424 bool maximum_compaction = clear_all_soft_refs; 425 PSParallelCompact::invoke(maximum_compaction); 426 } else { 427 PSMarkSweep::invoke(clear_all_soft_refs); 428 } 429 } 430 431 // Failed allocation policy. Must be called from the VM thread, and 432 // only at a safepoint! Note that this method has policy for allocation 433 // flow, and NOT collection policy. So we do not check for gc collection 434 // time over limit here, that is the responsibility of the heap specific 435 // collection methods. This method decides where to attempt allocations, 436 // and when to attempt collections, but no collection specific policy. 437 HeapWord* ParallelScavengeHeap::failed_mem_allocate(size_t size) { 438 assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); 439 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); 440 assert(!Universe::heap()->is_gc_active(), "not reentrant"); 441 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); 442 443 // We assume that allocation in eden will fail unless we collect. 444 445 // First level allocation failure, scavenge and allocate in young gen. 446 GCCauseSetter gccs(this, GCCause::_allocation_failure); 447 const bool invoked_full_gc = PSScavenge::invoke(); 448 HeapWord* result = young_gen()->allocate(size); 449 450 // Second level allocation failure. 451 // Mark sweep and allocate in young generation. 452 if (result == NULL && !invoked_full_gc) { 453 do_full_collection(false); 454 result = young_gen()->allocate(size); 455 } 456 457 death_march_check(result, size); 458 459 // Third level allocation failure. 460 // After mark sweep and young generation allocation failure, 461 // allocate in old generation. 462 if (result == NULL) { 463 result = old_gen()->allocate(size); 464 } 465 466 // Fourth level allocation failure. We're running out of memory. 467 // More complete mark sweep and allocate in young generation. 468 if (result == NULL) { 469 do_full_collection(true); 470 result = young_gen()->allocate(size); 471 } 472 473 // Fifth level allocation failure. 474 // After more complete mark sweep, allocate in old generation. 475 if (result == NULL) { 476 result = old_gen()->allocate(size); 477 } 478 479 return result; 480 } 481 482 void ParallelScavengeHeap::ensure_parsability(bool retire_tlabs) { 483 CollectedHeap::ensure_parsability(retire_tlabs); 484 young_gen()->eden_space()->ensure_parsability(); 485 } 486 487 size_t ParallelScavengeHeap::unsafe_max_alloc() { 488 return young_gen()->eden_space()->free_in_bytes(); 489 } 490 491 size_t ParallelScavengeHeap::tlab_capacity(Thread* thr) const { 492 return young_gen()->eden_space()->tlab_capacity(thr); 493 } 494 495 size_t ParallelScavengeHeap::unsafe_max_tlab_alloc(Thread* thr) const { 496 return young_gen()->eden_space()->unsafe_max_tlab_alloc(thr); 497 } 498 499 HeapWord* ParallelScavengeHeap::allocate_new_tlab(size_t size) { 500 return young_gen()->allocate(size); 501 } 502 503 void ParallelScavengeHeap::accumulate_statistics_all_tlabs() { 504 CollectedHeap::accumulate_statistics_all_tlabs(); 505 } 506 507 void ParallelScavengeHeap::resize_all_tlabs() { 508 CollectedHeap::resize_all_tlabs(); 509 } 510 511 bool ParallelScavengeHeap::can_elide_initializing_store_barrier(oop new_obj) { 512 // We don't need barriers for stores to objects in the 513 // young gen and, a fortiori, for initializing stores to 514 // objects therein. 515 return is_in_young(new_obj); 516 } 517 518 // This method is used by System.gc() and JVMTI. 519 void ParallelScavengeHeap::collect(GCCause::Cause cause) { 520 assert(!Heap_lock->owned_by_self(), 521 "this thread should not own the Heap_lock"); 522 523 unsigned int gc_count = 0; 524 unsigned int full_gc_count = 0; 525 { 526 MutexLocker ml(Heap_lock); 527 // This value is guarded by the Heap_lock 528 gc_count = Universe::heap()->total_collections(); 529 full_gc_count = Universe::heap()->total_full_collections(); 530 } 531 532 VM_ParallelGCSystemGC op(gc_count, full_gc_count, cause); 533 VMThread::execute(&op); 534 } 535 536 void ParallelScavengeHeap::oop_iterate(ExtendedOopClosure* cl) { 537 Unimplemented(); 538 } 539 540 void ParallelScavengeHeap::object_iterate(ObjectClosure* cl) { 541 young_gen()->object_iterate(cl); 542 old_gen()->object_iterate(cl); 543 } 544 545 546 HeapWord* ParallelScavengeHeap::block_start(const void* addr) const { 547 if (young_gen()->is_in_reserved(addr)) { 548 assert(young_gen()->is_in(addr), 549 "addr should be in allocated part of young gen"); 550 // called from os::print_location by find or VMError 551 if (Debugging || VMError::fatal_error_in_progress()) return NULL; 552 Unimplemented(); 553 } else if (old_gen()->is_in_reserved(addr)) { 554 assert(old_gen()->is_in(addr), 555 "addr should be in allocated part of old gen"); 556 return old_gen()->start_array()->object_start((HeapWord*)addr); 557 } 558 return 0; 559 } 560 561 size_t ParallelScavengeHeap::block_size(const HeapWord* addr) const { 562 return oop(addr)->size(); 563 } 564 565 bool ParallelScavengeHeap::block_is_obj(const HeapWord* addr) const { 566 return block_start(addr) == addr; 567 } 568 569 jlong ParallelScavengeHeap::millis_since_last_gc() { 570 return UseParallelOldGC ? 571 PSParallelCompact::millis_since_last_gc() : 572 PSMarkSweep::millis_since_last_gc(); 573 } 574 575 void ParallelScavengeHeap::prepare_for_verify() { 576 ensure_parsability(false); // no need to retire TLABs for verification 577 } 578 579 PSHeapSummary ParallelScavengeHeap::create_ps_heap_summary() { 580 PSOldGen* old = old_gen(); 581 HeapWord* old_committed_end = (HeapWord*)old->virtual_space()->committed_high_addr(); 582 VirtualSpaceSummary old_summary(old->reserved().start(), old_committed_end, old->reserved().end()); 583 SpaceSummary old_space(old->reserved().start(), old_committed_end, old->used_in_bytes()); 584 585 PSYoungGen* young = young_gen(); 586 VirtualSpaceSummary young_summary(young->reserved().start(), 587 (HeapWord*)young->virtual_space()->committed_high_addr(), young->reserved().end()); 588 589 MutableSpace* eden = young_gen()->eden_space(); 590 SpaceSummary eden_space(eden->bottom(), eden->end(), eden->used_in_bytes()); 591 592 MutableSpace* from = young_gen()->from_space(); 593 SpaceSummary from_space(from->bottom(), from->end(), from->used_in_bytes()); 594 595 MutableSpace* to = young_gen()->to_space(); 596 SpaceSummary to_space(to->bottom(), to->end(), to->used_in_bytes()); 597 598 VirtualSpaceSummary heap_summary = create_heap_space_summary(); 599 return PSHeapSummary(heap_summary, used(), old_summary, old_space, young_summary, eden_space, from_space, to_space); 600 } 601 602 void ParallelScavengeHeap::print_on(outputStream* st) const { 603 young_gen()->print_on(st); 604 old_gen()->print_on(st); 605 MetaspaceAux::print_on(st); 606 } 607 608 void ParallelScavengeHeap::print_on_error(outputStream* st) const { 609 this->CollectedHeap::print_on_error(st); 610 611 if (UseParallelOldGC) { 612 st->cr(); 613 PSParallelCompact::print_on_error(st); 614 } 615 } 616 617 void ParallelScavengeHeap::gc_threads_do(ThreadClosure* tc) const { 618 PSScavenge::gc_task_manager()->threads_do(tc); 619 } 620 621 void ParallelScavengeHeap::print_gc_threads_on(outputStream* st) const { 622 PSScavenge::gc_task_manager()->print_threads_on(st); 623 } 624 625 void ParallelScavengeHeap::print_tracing_info() const { 626 if (TraceGen0Time) { 627 double time = PSScavenge::accumulated_time()->seconds(); 628 tty->print_cr("[Accumulated GC generation 0 time %3.7f secs]", time); 629 } 630 if (TraceGen1Time) { 631 double time = UseParallelOldGC ? PSParallelCompact::accumulated_time()->seconds() : PSMarkSweep::accumulated_time()->seconds(); 632 tty->print_cr("[Accumulated GC generation 1 time %3.7f secs]", time); 633 } 634 } 635 636 637 void ParallelScavengeHeap::verify(bool silent, VerifyOption option /* ignored */) { 638 // Why do we need the total_collections()-filter below? 639 if (total_collections() > 0) { 640 if (!silent) { 641 gclog_or_tty->print("tenured "); 642 } 643 old_gen()->verify(); 644 645 if (!silent) { 646 gclog_or_tty->print("eden "); 647 } 648 young_gen()->verify(); 649 } 650 } 651 652 void ParallelScavengeHeap::print_heap_change(size_t prev_used) { 653 if (PrintGCDetails && Verbose) { 654 gclog_or_tty->print(" " SIZE_FORMAT 655 "->" SIZE_FORMAT 656 "(" SIZE_FORMAT ")", 657 prev_used, used(), capacity()); 658 } else { 659 gclog_or_tty->print(" " SIZE_FORMAT "K" 660 "->" SIZE_FORMAT "K" 661 "(" SIZE_FORMAT "K)", 662 prev_used / K, used() / K, capacity() / K); 663 } 664 } 665 666 void ParallelScavengeHeap::trace_heap(GCWhen::Type when, GCTracer* gc_tracer) { 667 const PSHeapSummary& heap_summary = create_ps_heap_summary(); 668 const MetaspaceSummary& metaspace_summary = create_metaspace_summary(); 669 gc_tracer->report_gc_heap_summary(when, heap_summary, metaspace_summary); 670 } 671 672 ParallelScavengeHeap* ParallelScavengeHeap::heap() { 673 assert(_psh != NULL, "Uninitialized access to ParallelScavengeHeap::heap()"); 674 assert(_psh->kind() == CollectedHeap::ParallelScavengeHeap, "not a parallel scavenge heap"); 675 return _psh; 676 } 677 678 // Before delegating the resize to the young generation, 679 // the reserved space for the young and old generations 680 // may be changed to accomodate the desired resize. 681 void ParallelScavengeHeap::resize_young_gen(size_t eden_size, 682 size_t survivor_size) { 683 if (UseAdaptiveGCBoundary) { 684 if (size_policy()->bytes_absorbed_from_eden() != 0) { 685 size_policy()->reset_bytes_absorbed_from_eden(); 686 return; // The generation changed size already. 687 } 688 gens()->adjust_boundary_for_young_gen_needs(eden_size, survivor_size); 689 } 690 691 // Delegate the resize to the generation. 692 _young_gen->resize(eden_size, survivor_size); 693 } 694 695 // Before delegating the resize to the old generation, 696 // the reserved space for the young and old generations 697 // may be changed to accomodate the desired resize. 698 void ParallelScavengeHeap::resize_old_gen(size_t desired_free_space) { 699 if (UseAdaptiveGCBoundary) { 700 if (size_policy()->bytes_absorbed_from_eden() != 0) { 701 size_policy()->reset_bytes_absorbed_from_eden(); 702 return; // The generation changed size already. 703 } 704 gens()->adjust_boundary_for_old_gen_needs(desired_free_space); 705 } 706 707 // Delegate the resize to the generation. 708 _old_gen->resize(desired_free_space); 709 } 710 711 ParallelScavengeHeap::ParStrongRootsScope::ParStrongRootsScope() { 712 // nothing particular 713 } 714 715 ParallelScavengeHeap::ParStrongRootsScope::~ParStrongRootsScope() { 716 // nothing particular 717 } 718 719 #ifndef PRODUCT 720 void ParallelScavengeHeap::record_gen_tops_before_GC() { 721 if (ZapUnusedHeapArea) { 722 young_gen()->record_spaces_top(); 723 old_gen()->record_spaces_top(); 724 } 725 } 726 727 void ParallelScavengeHeap::gen_mangle_unused_area() { 728 if (ZapUnusedHeapArea) { 729 young_gen()->eden_space()->mangle_unused_area(); 730 young_gen()->to_space()->mangle_unused_area(); 731 young_gen()->from_space()->mangle_unused_area(); 732 old_gen()->object_space()->mangle_unused_area(); 733 } 734 } 735 #endif