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 _gens = new AdjoiningGenerations(heap_rs, _collector_policy, generation_alignment());
93
94 _old_gen = _gens->old_gen();
95 _young_gen = _gens->young_gen();
96
97 const size_t eden_capacity = _young_gen->eden_space()->capacity_in_bytes();
98 const size_t old_capacity = _old_gen->capacity_in_bytes();
99 const size_t initial_promo_size = MIN2(eden_capacity, old_capacity);
100 _size_policy =
101 new PSAdaptiveSizePolicy(eden_capacity,
102 initial_promo_size,
103 young_gen()->to_space()->capacity_in_bytes(),
104 _collector_policy->gen_alignment(),
105 max_gc_pause_sec,
106 max_gc_minor_pause_sec,
107 GCTimeRatio
108 );
109
110 assert(!UseAdaptiveGCBoundary ||
111 (old_gen()->virtual_space()->high_boundary() ==
112 young_gen()->virtual_space()->low_boundary()),
113 "Boundaries must meet");
114 // initialize the policy counters - 2 collectors, 3 generations
115 _gc_policy_counters =
116 new PSGCAdaptivePolicyCounters("ParScav:MSC", 2, 3, _size_policy);
117 _psh = this;
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 = Universe::heap()->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(Universe::heap()->is_in_or_null(op.result()),
313 "result not in heap");
314
315 // If GC was locked out during VM operation then retry allocation
316 // and/or stall as necessary.
317 if (op.gc_locked()) {
318 assert(op.result() == NULL, "must be NULL if gc_locked() is true");
319 continue; // retry and/or stall as necessary
320 }
321
322 // Exit the loop if the gc time limit has been exceeded.
323 // The allocation must have failed above ("result" guarding
324 // this path is NULL) and the most recent collection has exceeded the
325 // gc overhead limit (although enough may have been collected to
326 // satisfy the allocation). Exit the loop so that an out-of-memory
327 // will be thrown (return a NULL ignoring the contents of
328 // op.result()),
329 // but clear gc_overhead_limit_exceeded so that the next collection
330 // starts with a clean slate (i.e., forgets about previous overhead
331 // excesses). Fill op.result() with a filler object so that the
332 // heap remains parsable.
333 const bool limit_exceeded = size_policy()->gc_overhead_limit_exceeded();
334 const bool softrefs_clear = collector_policy()->all_soft_refs_clear();
335
336 if (limit_exceeded && softrefs_clear) {
337 *gc_overhead_limit_was_exceeded = true;
338 size_policy()->set_gc_overhead_limit_exceeded(false);
339 if (PrintGCDetails && Verbose) {
340 gclog_or_tty->print_cr("ParallelScavengeHeap::mem_allocate: "
341 "return NULL because gc_overhead_limit_exceeded is set");
342 }
343 if (op.result() != NULL) {
344 CollectedHeap::fill_with_object(op.result(), size);
345 }
346 return NULL;
347 }
348
349 return op.result();
350 }
351 }
352
353 // The policy object will prevent us from looping forever. If the
354 // time spent in gc crosses a threshold, we will bail out.
355 loop_count++;
356 if ((result == NULL) && (QueuedAllocationWarningCount > 0) &&
357 (loop_count % QueuedAllocationWarningCount == 0)) {
358 warning("ParallelScavengeHeap::mem_allocate retries %d times \n\t"
359 " size=" SIZE_FORMAT, loop_count, size);
360 }
361 }
362
363 return result;
364 }
365
366 // A "death march" is a series of ultra-slow allocations in which a full gc is
367 // done before each allocation, and after the full gc the allocation still
368 // cannot be satisfied from the young gen. This routine detects that condition;
369 // it should be called after a full gc has been done and the allocation
370 // attempted from the young gen. The parameter 'addr' should be the result of
371 // that young gen allocation attempt.
372 void
373 ParallelScavengeHeap::death_march_check(HeapWord* const addr, size_t size) {
374 if (addr != NULL) {
375 _death_march_count = 0; // death march has ended
376 } else if (_death_march_count == 0) {
377 if (should_alloc_in_eden(size)) {
378 _death_march_count = 1; // death march has started
379 }
380 }
381 }
382
383 HeapWord* ParallelScavengeHeap::mem_allocate_old_gen(size_t size) {
384 if (!should_alloc_in_eden(size) || GC_locker::is_active_and_needs_gc()) {
385 // Size is too big for eden, or gc is locked out.
386 return old_gen()->allocate(size);
387 }
388
389 // If a "death march" is in progress, allocate from the old gen a limited
390 // number of times before doing a GC.
391 if (_death_march_count > 0) {
392 if (_death_march_count < 64) {
393 ++_death_march_count;
394 return old_gen()->allocate(size);
395 } else {
396 _death_march_count = 0;
397 }
398 }
399 return NULL;
400 }
401
402 void ParallelScavengeHeap::do_full_collection(bool clear_all_soft_refs) {
403 if (UseParallelOldGC) {
404 // The do_full_collection() parameter clear_all_soft_refs
405 // is interpreted here as maximum_compaction which will
406 // cause SoftRefs to be cleared.
407 bool maximum_compaction = clear_all_soft_refs;
408 PSParallelCompact::invoke(maximum_compaction);
409 } else {
410 PSMarkSweep::invoke(clear_all_soft_refs);
411 }
412 }
413
414 // Failed allocation policy. Must be called from the VM thread, and
415 // only at a safepoint! Note that this method has policy for allocation
416 // flow, and NOT collection policy. So we do not check for gc collection
417 // time over limit here, that is the responsibility of the heap specific
418 // collection methods. This method decides where to attempt allocations,
419 // and when to attempt collections, but no collection specific policy.
420 HeapWord* ParallelScavengeHeap::failed_mem_allocate(size_t size) {
421 assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint");
422 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
423 assert(!Universe::heap()->is_gc_active(), "not reentrant");
424 assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock");
425
426 // We assume that allocation in eden will fail unless we collect.
427
428 // First level allocation failure, scavenge and allocate in young gen.
429 GCCauseSetter gccs(this, GCCause::_allocation_failure);
430 const bool invoked_full_gc = PSScavenge::invoke();
431 HeapWord* result = young_gen()->allocate(size);
432
433 // Second level allocation failure.
434 // Mark sweep and allocate in young generation.
435 if (result == NULL && !invoked_full_gc) {
436 do_full_collection(false);
437 result = young_gen()->allocate(size);
438 }
439
440 death_march_check(result, size);
441
442 // Third level allocation failure.
443 // After mark sweep and young generation allocation failure,
444 // allocate in old generation.
445 if (result == NULL) {
446 result = old_gen()->allocate(size);
447 }
448
449 // Fourth level allocation failure. We're running out of memory.
450 // More complete mark sweep and allocate in young generation.
451 if (result == NULL) {
452 do_full_collection(true);
453 result = young_gen()->allocate(size);
454 }
455
456 // Fifth level allocation failure.
457 // After more complete mark sweep, allocate in old generation.
458 if (result == NULL) {
459 result = old_gen()->allocate(size);
460 }
461
462 return result;
463 }
464
465 void ParallelScavengeHeap::ensure_parsability(bool retire_tlabs) {
466 CollectedHeap::ensure_parsability(retire_tlabs);
467 young_gen()->eden_space()->ensure_parsability();
468 }
469
470 size_t ParallelScavengeHeap::tlab_capacity(Thread* thr) const {
471 return young_gen()->eden_space()->tlab_capacity(thr);
472 }
473
474 size_t ParallelScavengeHeap::tlab_used(Thread* thr) const {
475 return young_gen()->eden_space()->tlab_used(thr);
476 }
477
478 size_t ParallelScavengeHeap::unsafe_max_tlab_alloc(Thread* thr) const {
479 return young_gen()->eden_space()->unsafe_max_tlab_alloc(thr);
480 }
481
482 HeapWord* ParallelScavengeHeap::allocate_new_tlab(size_t size) {
483 return young_gen()->allocate(size);
484 }
485
486 void ParallelScavengeHeap::accumulate_statistics_all_tlabs() {
487 CollectedHeap::accumulate_statistics_all_tlabs();
488 }
489
490 void ParallelScavengeHeap::resize_all_tlabs() {
491 CollectedHeap::resize_all_tlabs();
492 }
493
494 bool ParallelScavengeHeap::can_elide_initializing_store_barrier(oop new_obj) {
495 // We don't need barriers for stores to objects in the
496 // young gen and, a fortiori, for initializing stores to
497 // objects therein.
498 return is_in_young(new_obj);
499 }
500
501 // This method is used by System.gc() and JVMTI.
502 void ParallelScavengeHeap::collect(GCCause::Cause cause) {
503 assert(!Heap_lock->owned_by_self(),
504 "this thread should not own the Heap_lock");
505
506 uint gc_count = 0;
507 uint full_gc_count = 0;
508 {
509 MutexLocker ml(Heap_lock);
510 // This value is guarded by the Heap_lock
511 gc_count = Universe::heap()->total_collections();
512 full_gc_count = Universe::heap()->total_full_collections();
513 }
514
515 VM_ParallelGCSystemGC op(gc_count, full_gc_count, cause);
516 VMThread::execute(&op);
517 }
518
519 void ParallelScavengeHeap::object_iterate(ObjectClosure* cl) {
520 young_gen()->object_iterate(cl);
521 old_gen()->object_iterate(cl);
522 }
523
524
525 HeapWord* ParallelScavengeHeap::block_start(const void* addr) const {
526 if (young_gen()->is_in_reserved(addr)) {
527 assert(young_gen()->is_in(addr),
528 "addr should be in allocated part of young gen");
529 // called from os::print_location by find or VMError
530 if (Debugging || VMError::fatal_error_in_progress()) return NULL;
531 Unimplemented();
532 } else if (old_gen()->is_in_reserved(addr)) {
533 assert(old_gen()->is_in(addr),
534 "addr should be in allocated part of old gen");
535 return old_gen()->start_array()->object_start((HeapWord*)addr);
536 }
537 return 0;
538 }
539
540 size_t ParallelScavengeHeap::block_size(const HeapWord* addr) const {
541 return oop(addr)->size();
542 }
543
544 bool ParallelScavengeHeap::block_is_obj(const HeapWord* addr) const {
545 return block_start(addr) == addr;
546 }
547
548 jlong ParallelScavengeHeap::millis_since_last_gc() {
549 return UseParallelOldGC ?
550 PSParallelCompact::millis_since_last_gc() :
551 PSMarkSweep::millis_since_last_gc();
552 }
553
554 void ParallelScavengeHeap::prepare_for_verify() {
555 ensure_parsability(false); // no need to retire TLABs for verification
556 }
557
558 PSHeapSummary ParallelScavengeHeap::create_ps_heap_summary() {
559 PSOldGen* old = old_gen();
560 HeapWord* old_committed_end = (HeapWord*)old->virtual_space()->committed_high_addr();
561 VirtualSpaceSummary old_summary(old->reserved().start(), old_committed_end, old->reserved().end());
562 SpaceSummary old_space(old->reserved().start(), old_committed_end, old->used_in_bytes());
563
564 PSYoungGen* young = young_gen();
565 VirtualSpaceSummary young_summary(young->reserved().start(),
566 (HeapWord*)young->virtual_space()->committed_high_addr(), young->reserved().end());
567
568 MutableSpace* eden = young_gen()->eden_space();
569 SpaceSummary eden_space(eden->bottom(), eden->end(), eden->used_in_bytes());
570
571 MutableSpace* from = young_gen()->from_space();
572 SpaceSummary from_space(from->bottom(), from->end(), from->used_in_bytes());
573
574 MutableSpace* to = young_gen()->to_space();
575 SpaceSummary to_space(to->bottom(), to->end(), to->used_in_bytes());
576
577 VirtualSpaceSummary heap_summary = create_heap_space_summary();
578 return PSHeapSummary(heap_summary, used(), old_summary, old_space, young_summary, eden_space, from_space, to_space);
579 }
580
581 void ParallelScavengeHeap::print_on(outputStream* st) const {
582 young_gen()->print_on(st);
583 old_gen()->print_on(st);
584 MetaspaceAux::print_on(st);
585 }
586
587 void ParallelScavengeHeap::print_on_error(outputStream* st) const {
588 this->CollectedHeap::print_on_error(st);
589
590 if (UseParallelOldGC) {
591 st->cr();
592 PSParallelCompact::print_on_error(st);
593 }
594 }
595
596 void ParallelScavengeHeap::gc_threads_do(ThreadClosure* tc) const {
597 PSScavenge::gc_task_manager()->threads_do(tc);
598 }
599
600 void ParallelScavengeHeap::print_gc_threads_on(outputStream* st) const {
601 PSScavenge::gc_task_manager()->print_threads_on(st);
602 }
603
604 void ParallelScavengeHeap::print_tracing_info() const {
605 if (TraceYoungGenTime) {
606 double time = PSScavenge::accumulated_time()->seconds();
607 tty->print_cr("[Accumulated GC generation 0 time %3.7f secs]", time);
608 }
609 if (TraceOldGenTime) {
610 double time = UseParallelOldGC ? PSParallelCompact::accumulated_time()->seconds() : PSMarkSweep::accumulated_time()->seconds();
611 tty->print_cr("[Accumulated GC generation 1 time %3.7f secs]", time);
612 }
613 }
614
615
616 void ParallelScavengeHeap::verify(bool silent, VerifyOption option /* ignored */) {
617 // Why do we need the total_collections()-filter below?
618 if (total_collections() > 0) {
619 if (!silent) {
620 gclog_or_tty->print("tenured ");
621 }
622 old_gen()->verify();
623
624 if (!silent) {
625 gclog_or_tty->print("eden ");
626 }
627 young_gen()->verify();
628 }
629 }
630
631 void ParallelScavengeHeap::print_heap_change(size_t prev_used) {
632 if (PrintGCDetails && Verbose) {
633 gclog_or_tty->print(" " SIZE_FORMAT
634 "->" SIZE_FORMAT
635 "(" SIZE_FORMAT ")",
636 prev_used, used(), capacity());
637 } else {
638 gclog_or_tty->print(" " SIZE_FORMAT "K"
639 "->" SIZE_FORMAT "K"
640 "(" SIZE_FORMAT "K)",
641 prev_used / K, used() / K, capacity() / K);
642 }
643 }
644
645 void ParallelScavengeHeap::trace_heap(GCWhen::Type when, const GCTracer* gc_tracer) {
646 const PSHeapSummary& heap_summary = create_ps_heap_summary();
647 gc_tracer->report_gc_heap_summary(when, heap_summary);
648
649 const MetaspaceSummary& metaspace_summary = create_metaspace_summary();
650 gc_tracer->report_metaspace_summary(when, metaspace_summary);
651 }
652
653 ParallelScavengeHeap* ParallelScavengeHeap::heap() {
654 assert(_psh != NULL, "Uninitialized access to ParallelScavengeHeap::heap()");
655 assert(_psh->kind() == CollectedHeap::ParallelScavengeHeap, "not a parallel scavenge heap");
656 return _psh;
657 }
658
659 // Before delegating the resize to the young generation,
660 // the reserved space for the young and old generations
661 // may be changed to accommodate the desired resize.
662 void ParallelScavengeHeap::resize_young_gen(size_t eden_size,
663 size_t survivor_size) {
664 if (UseAdaptiveGCBoundary) {
665 if (size_policy()->bytes_absorbed_from_eden() != 0) {
666 size_policy()->reset_bytes_absorbed_from_eden();
667 return; // The generation changed size already.
668 }
669 gens()->adjust_boundary_for_young_gen_needs(eden_size, survivor_size);
670 }
671
672 // Delegate the resize to the generation.
673 _young_gen->resize(eden_size, survivor_size);
674 }
675
676 // Before delegating the resize to the old generation,
677 // the reserved space for the young and old generations
678 // may be changed to accommodate the desired resize.
679 void ParallelScavengeHeap::resize_old_gen(size_t desired_free_space) {
680 if (UseAdaptiveGCBoundary) {
681 if (size_policy()->bytes_absorbed_from_eden() != 0) {
682 size_policy()->reset_bytes_absorbed_from_eden();
683 return; // The generation changed size already.
684 }
685 gens()->adjust_boundary_for_old_gen_needs(desired_free_space);
686 }
687
688 // Delegate the resize to the generation.
689 _old_gen->resize(desired_free_space);
690 }
691
692 ParallelScavengeHeap::ParStrongRootsScope::ParStrongRootsScope() {
693 // nothing particular
694 }
695
696 ParallelScavengeHeap::ParStrongRootsScope::~ParStrongRootsScope() {
697 // nothing particular
698 }
699
700 #ifndef PRODUCT
701 void ParallelScavengeHeap::record_gen_tops_before_GC() {
702 if (ZapUnusedHeapArea) {
703 young_gen()->record_spaces_top();
704 old_gen()->record_spaces_top();
705 }
706 }
707
708 void ParallelScavengeHeap::gen_mangle_unused_area() {
709 if (ZapUnusedHeapArea) {
710 young_gen()->eden_space()->mangle_unused_area();
711 young_gen()->to_space()->mangle_unused_area();
712 young_gen()->from_space()->mangle_unused_area();
713 old_gen()->object_space()->mangle_unused_area();
714 }
715 }
716 #endif