Mercurial > hg > truffle
annotate src/share/vm/gc_implementation/parallelScavenge/psScavenge.cpp @ 2015:79d8657be916
6993125: runThese crashes with assert(Thread::current()->on_local_stack((address)this))
Summary: add another ResourceObj debug field to distinguish garbage
Reviewed-by: dholmes, coleenp
author | kvn |
---|---|
date | Fri, 10 Dec 2010 14:14:02 -0800 |
parents | f95d63e2154a |
children | 74ee0db180fa |
rev | line source |
---|---|
0 | 1 /* |
1552
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
1387
diff
changeset
|
2 * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved. |
0 | 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 * | |
1552
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
1387
diff
changeset
|
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
1387
diff
changeset
|
20 * or visit www.oracle.com if you need additional information or have any |
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
1387
diff
changeset
|
21 * questions. |
0 | 22 * |
23 */ | |
24 | |
1972 | 25 #include "precompiled.hpp" |
26 #include "gc_implementation/parallelScavenge/cardTableExtension.hpp" | |
27 #include "gc_implementation/parallelScavenge/gcTaskManager.hpp" | |
28 #include "gc_implementation/parallelScavenge/generationSizer.hpp" | |
29 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp" | |
30 #include "gc_implementation/parallelScavenge/psAdaptiveSizePolicy.hpp" | |
31 #include "gc_implementation/parallelScavenge/psMarkSweep.hpp" | |
32 #include "gc_implementation/parallelScavenge/psParallelCompact.hpp" | |
33 #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp" | |
34 #include "gc_implementation/parallelScavenge/psTasks.hpp" | |
35 #include "gc_implementation/shared/isGCActiveMark.hpp" | |
36 #include "gc_implementation/shared/spaceDecorator.hpp" | |
37 #include "gc_interface/gcCause.hpp" | |
38 #include "memory/collectorPolicy.hpp" | |
39 #include "memory/gcLocker.inline.hpp" | |
40 #include "memory/referencePolicy.hpp" | |
41 #include "memory/referenceProcessor.hpp" | |
42 #include "memory/resourceArea.hpp" | |
43 #include "oops/oop.inline.hpp" | |
44 #include "oops/oop.psgc.inline.hpp" | |
45 #include "runtime/biasedLocking.hpp" | |
46 #include "runtime/fprofiler.hpp" | |
47 #include "runtime/handles.inline.hpp" | |
48 #include "runtime/threadCritical.hpp" | |
49 #include "runtime/vmThread.hpp" | |
50 #include "runtime/vm_operations.hpp" | |
51 #include "services/memoryService.hpp" | |
52 #include "utilities/stack.inline.hpp" | |
0 | 53 |
54 | |
55 HeapWord* PSScavenge::_to_space_top_before_gc = NULL; | |
56 int PSScavenge::_consecutive_skipped_scavenges = 0; | |
57 ReferenceProcessor* PSScavenge::_ref_processor = NULL; | |
58 CardTableExtension* PSScavenge::_card_table = NULL; | |
59 bool PSScavenge::_survivor_overflow = false; | |
60 int PSScavenge::_tenuring_threshold = 0; | |
61 HeapWord* PSScavenge::_young_generation_boundary = NULL; | |
62 elapsedTimer PSScavenge::_accumulated_time; | |
1836
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
63 Stack<markOop> PSScavenge::_preserved_mark_stack; |
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
64 Stack<oop> PSScavenge::_preserved_oop_stack; |
0 | 65 CollectorCounters* PSScavenge::_counters = NULL; |
1836
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
66 bool PSScavenge::_promotion_failed = false; |
0 | 67 |
68 // Define before use | |
69 class PSIsAliveClosure: public BoolObjectClosure { | |
70 public: | |
71 void do_object(oop p) { | |
72 assert(false, "Do not call."); | |
73 } | |
74 bool do_object_b(oop p) { | |
75 return (!PSScavenge::is_obj_in_young((HeapWord*) p)) || p->is_forwarded(); | |
76 } | |
77 }; | |
78 | |
79 PSIsAliveClosure PSScavenge::_is_alive_closure; | |
80 | |
81 class PSKeepAliveClosure: public OopClosure { | |
82 protected: | |
83 MutableSpace* _to_space; | |
84 PSPromotionManager* _promotion_manager; | |
85 | |
86 public: | |
87 PSKeepAliveClosure(PSPromotionManager* pm) : _promotion_manager(pm) { | |
88 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); | |
89 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); | |
90 _to_space = heap->young_gen()->to_space(); | |
91 | |
92 assert(_promotion_manager != NULL, "Sanity"); | |
93 } | |
94 | |
113
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
95 template <class T> void do_oop_work(T* p) { |
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
96 assert (!oopDesc::is_null(*p), "expected non-null ref"); |
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
97 assert ((oopDesc::load_decode_heap_oop_not_null(p))->is_oop(), |
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
98 "expected an oop while scanning weak refs"); |
0 | 99 |
100 // Weak refs may be visited more than once. | |
113
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
101 if (PSScavenge::should_scavenge(p, _to_space)) { |
0 | 102 PSScavenge::copy_and_push_safe_barrier(_promotion_manager, p); |
103 } | |
104 } | |
113
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
105 virtual void do_oop(oop* p) { PSKeepAliveClosure::do_oop_work(p); } |
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
106 virtual void do_oop(narrowOop* p) { PSKeepAliveClosure::do_oop_work(p); } |
0 | 107 }; |
108 | |
109 class PSEvacuateFollowersClosure: public VoidClosure { | |
110 private: | |
111 PSPromotionManager* _promotion_manager; | |
112 public: | |
113 PSEvacuateFollowersClosure(PSPromotionManager* pm) : _promotion_manager(pm) {} | |
114 | |
113
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
115 virtual void do_void() { |
0 | 116 assert(_promotion_manager != NULL, "Sanity"); |
117 _promotion_manager->drain_stacks(true); | |
118 guarantee(_promotion_manager->stacks_empty(), | |
119 "stacks should be empty at this point"); | |
120 } | |
121 }; | |
122 | |
123 class PSPromotionFailedClosure : public ObjectClosure { | |
124 virtual void do_object(oop obj) { | |
125 if (obj->is_forwarded()) { | |
126 obj->init_mark(); | |
127 } | |
128 } | |
129 }; | |
130 | |
131 class PSRefProcTaskProxy: public GCTask { | |
132 typedef AbstractRefProcTaskExecutor::ProcessTask ProcessTask; | |
133 ProcessTask & _rp_task; | |
134 uint _work_id; | |
135 public: | |
136 PSRefProcTaskProxy(ProcessTask & rp_task, uint work_id) | |
137 : _rp_task(rp_task), | |
138 _work_id(work_id) | |
139 { } | |
140 | |
141 private: | |
142 virtual char* name() { return (char *)"Process referents by policy in parallel"; } | |
143 virtual void do_it(GCTaskManager* manager, uint which); | |
144 }; | |
145 | |
146 void PSRefProcTaskProxy::do_it(GCTaskManager* manager, uint which) | |
147 { | |
148 PSPromotionManager* promotion_manager = | |
149 PSPromotionManager::gc_thread_promotion_manager(which); | |
150 assert(promotion_manager != NULL, "sanity check"); | |
151 PSKeepAliveClosure keep_alive(promotion_manager); | |
152 PSEvacuateFollowersClosure evac_followers(promotion_manager); | |
153 PSIsAliveClosure is_alive; | |
154 _rp_task.work(_work_id, is_alive, keep_alive, evac_followers); | |
155 } | |
156 | |
157 class PSRefEnqueueTaskProxy: public GCTask { | |
158 typedef AbstractRefProcTaskExecutor::EnqueueTask EnqueueTask; | |
159 EnqueueTask& _enq_task; | |
160 uint _work_id; | |
161 | |
162 public: | |
163 PSRefEnqueueTaskProxy(EnqueueTask& enq_task, uint work_id) | |
164 : _enq_task(enq_task), | |
165 _work_id(work_id) | |
166 { } | |
167 | |
168 virtual char* name() { return (char *)"Enqueue reference objects in parallel"; } | |
169 virtual void do_it(GCTaskManager* manager, uint which) | |
170 { | |
171 _enq_task.work(_work_id); | |
172 } | |
173 }; | |
174 | |
175 class PSRefProcTaskExecutor: public AbstractRefProcTaskExecutor { | |
176 virtual void execute(ProcessTask& task); | |
177 virtual void execute(EnqueueTask& task); | |
178 }; | |
179 | |
180 void PSRefProcTaskExecutor::execute(ProcessTask& task) | |
181 { | |
182 GCTaskQueue* q = GCTaskQueue::create(); | |
183 for(uint i=0; i<ParallelGCThreads; i++) { | |
184 q->enqueue(new PSRefProcTaskProxy(task, i)); | |
185 } | |
186 ParallelTaskTerminator terminator( | |
1706
9d7a8ab3736b
6962589: remove breadth first scanning code from parallel gc
tonyp
parents:
1638
diff
changeset
|
187 ParallelScavengeHeap::gc_task_manager()->workers(), |
9d7a8ab3736b
6962589: remove breadth first scanning code from parallel gc
tonyp
parents:
1638
diff
changeset
|
188 (TaskQueueSetSuper*) PSPromotionManager::stack_array_depth()); |
0 | 189 if (task.marks_oops_alive() && ParallelGCThreads > 1) { |
190 for (uint j=0; j<ParallelGCThreads; j++) { | |
191 q->enqueue(new StealTask(&terminator)); | |
192 } | |
193 } | |
194 ParallelScavengeHeap::gc_task_manager()->execute_and_wait(q); | |
195 } | |
196 | |
197 | |
198 void PSRefProcTaskExecutor::execute(EnqueueTask& task) | |
199 { | |
200 GCTaskQueue* q = GCTaskQueue::create(); | |
201 for(uint i=0; i<ParallelGCThreads; i++) { | |
202 q->enqueue(new PSRefEnqueueTaskProxy(task, i)); | |
203 } | |
204 ParallelScavengeHeap::gc_task_manager()->execute_and_wait(q); | |
205 } | |
206 | |
207 // This method contains all heap specific policy for invoking scavenge. | |
208 // PSScavenge::invoke_no_policy() will do nothing but attempt to | |
209 // scavenge. It will not clean up after failed promotions, bail out if | |
210 // we've exceeded policy time limits, or any other special behavior. | |
211 // All such policy should be placed here. | |
212 // | |
213 // Note that this method should only be called from the vm_thread while | |
214 // at a safepoint! | |
1387
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
215 void PSScavenge::invoke() { |
0 | 216 assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); |
217 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); | |
218 assert(!Universe::heap()->is_gc_active(), "not reentrant"); | |
219 | |
220 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); | |
221 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); | |
222 | |
223 PSAdaptiveSizePolicy* policy = heap->size_policy(); | |
1387
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
224 IsGCActiveMark mark; |
0 | 225 |
1387
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
226 bool scavenge_was_done = PSScavenge::invoke_no_policy(); |
0 | 227 |
1387
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
228 PSGCAdaptivePolicyCounters* counters = heap->gc_policy_counters(); |
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
229 if (UsePerfData) |
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
230 counters->update_full_follows_scavenge(0); |
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
231 if (!scavenge_was_done || |
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
232 policy->should_full_GC(heap->old_gen()->free_in_bytes())) { |
0 | 233 if (UsePerfData) |
1387
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
234 counters->update_full_follows_scavenge(full_follows_scavenge); |
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
235 GCCauseSetter gccs(heap, GCCause::_adaptive_size_policy); |
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
236 CollectorPolicy* cp = heap->collector_policy(); |
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
237 const bool clear_all_softrefs = cp->should_clear_all_soft_refs(); |
0 | 238 |
1387
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
239 if (UseParallelOldGC) { |
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
240 PSParallelCompact::invoke_no_policy(clear_all_softrefs); |
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
241 } else { |
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
242 PSMarkSweep::invoke_no_policy(clear_all_softrefs); |
0 | 243 } |
244 } | |
245 } | |
246 | |
247 // This method contains no policy. You should probably | |
248 // be calling invoke() instead. | |
249 bool PSScavenge::invoke_no_policy() { | |
250 assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); | |
251 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); | |
252 | |
1836
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
253 assert(_preserved_mark_stack.is_empty(), "should be empty"); |
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
254 assert(_preserved_oop_stack.is_empty(), "should be empty"); |
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
255 |
0 | 256 TimeStamp scavenge_entry; |
257 TimeStamp scavenge_midpoint; | |
258 TimeStamp scavenge_exit; | |
259 | |
260 scavenge_entry.update(); | |
261 | |
262 if (GC_locker::check_active_before_gc()) { | |
263 return false; | |
264 } | |
265 | |
266 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); | |
267 GCCause::Cause gc_cause = heap->gc_cause(); | |
268 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); | |
269 | |
270 // Check for potential problems. | |
271 if (!should_attempt_scavenge()) { | |
272 return false; | |
273 } | |
274 | |
275 bool promotion_failure_occurred = false; | |
276 | |
277 PSYoungGen* young_gen = heap->young_gen(); | |
278 PSOldGen* old_gen = heap->old_gen(); | |
279 PSPermGen* perm_gen = heap->perm_gen(); | |
280 PSAdaptiveSizePolicy* size_policy = heap->size_policy(); | |
281 heap->increment_total_collections(); | |
282 | |
283 AdaptiveSizePolicyOutput(size_policy, heap->total_collections()); | |
284 | |
285 if ((gc_cause != GCCause::_java_lang_system_gc) || | |
286 UseAdaptiveSizePolicyWithSystemGC) { | |
287 // Gather the feedback data for eden occupancy. | |
288 young_gen->eden_space()->accumulate_statistics(); | |
289 } | |
290 | |
263
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
291 if (ZapUnusedHeapArea) { |
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
292 // Save information needed to minimize mangling |
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
293 heap->record_gen_tops_before_GC(); |
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
294 } |
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
295 |
0 | 296 if (PrintHeapAtGC) { |
297 Universe::print_heap_before_gc(); | |
298 } | |
299 | |
300 assert(!NeverTenure || _tenuring_threshold == markOopDesc::max_age + 1, "Sanity"); | |
301 assert(!AlwaysTenure || _tenuring_threshold == 0, "Sanity"); | |
302 | |
303 size_t prev_used = heap->used(); | |
304 assert(promotion_failed() == false, "Sanity"); | |
305 | |
306 // Fill in TLABs | |
307 heap->accumulate_statistics_all_tlabs(); | |
308 heap->ensure_parsability(true); // retire TLABs | |
309 | |
310 if (VerifyBeforeGC && heap->total_collections() >= VerifyGCStartAt) { | |
311 HandleMark hm; // Discard invalid handles created during verification | |
312 gclog_or_tty->print(" VerifyBeforeGC:"); | |
313 Universe::verify(true); | |
314 } | |
315 | |
316 { | |
317 ResourceMark rm; | |
318 HandleMark hm; | |
319 | |
320 gclog_or_tty->date_stamp(PrintGC && PrintGCDateStamps); | |
321 TraceCPUTime tcpu(PrintGCDetails, true, gclog_or_tty); | |
322 TraceTime t1("GC", PrintGC, !PrintGCDetails, gclog_or_tty); | |
323 TraceCollectorStats tcs(counters()); | |
324 TraceMemoryManagerStats tms(false /* not full GC */); | |
325 | |
326 if (TraceGen0Time) accumulated_time()->start(); | |
327 | |
328 // Let the size policy know we're starting | |
329 size_policy->minor_collection_begin(); | |
330 | |
331 // Verify the object start arrays. | |
332 if (VerifyObjectStartArray && | |
333 VerifyBeforeGC) { | |
334 old_gen->verify_object_start_array(); | |
335 perm_gen->verify_object_start_array(); | |
336 } | |
337 | |
338 // Verify no unmarked old->young roots | |
339 if (VerifyRememberedSets) { | |
340 CardTableExtension::verify_all_young_refs_imprecise(); | |
341 } | |
342 | |
343 if (!ScavengeWithObjectsInToSpace) { | |
344 assert(young_gen->to_space()->is_empty(), | |
345 "Attempt to scavenge with live objects in to_space"); | |
263
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
346 young_gen->to_space()->clear(SpaceDecorator::Mangle); |
0 | 347 } else if (ZapUnusedHeapArea) { |
348 young_gen->to_space()->mangle_unused_area(); | |
349 } | |
350 save_to_space_top_before_gc(); | |
351 | |
352 NOT_PRODUCT(reference_processor()->verify_no_references_recorded()); | |
353 COMPILER2_PRESENT(DerivedPointerTable::clear()); | |
354 | |
355 reference_processor()->enable_discovery(); | |
457
27a80744a83b
6778647: snap(), snap_policy() should be renamed setup(), setup_policy()
ysr
parents:
453
diff
changeset
|
356 reference_processor()->setup_policy(false); |
0 | 357 |
358 // We track how much was promoted to the next generation for | |
359 // the AdaptiveSizePolicy. | |
360 size_t old_gen_used_before = old_gen->used_in_bytes(); | |
361 | |
362 // For PrintGCDetails | |
363 size_t young_gen_used_before = young_gen->used_in_bytes(); | |
364 | |
365 // Reset our survivor overflow. | |
366 set_survivor_overflow(false); | |
367 | |
368 // We need to save the old/perm top values before | |
369 // creating the promotion_manager. We pass the top | |
370 // values to the card_table, to prevent it from | |
371 // straying into the promotion labs. | |
372 HeapWord* old_top = old_gen->object_space()->top(); | |
373 HeapWord* perm_top = perm_gen->object_space()->top(); | |
374 | |
375 // Release all previously held resources | |
376 gc_task_manager()->release_all_resources(); | |
377 | |
378 PSPromotionManager::pre_scavenge(); | |
379 | |
380 // We'll use the promotion manager again later. | |
381 PSPromotionManager* promotion_manager = PSPromotionManager::vm_thread_promotion_manager(); | |
382 { | |
383 // TraceTime("Roots"); | |
989
148e5441d916
6863023: need non-perm oops in code cache for JSR 292
jrose
parents:
579
diff
changeset
|
384 ParallelScavengeHeap::ParStrongRootsScope psrs; |
0 | 385 |
386 GCTaskQueue* q = GCTaskQueue::create(); | |
387 | |
388 for(uint i=0; i<ParallelGCThreads; i++) { | |
389 q->enqueue(new OldToYoungRootsTask(old_gen, old_top, i)); | |
390 } | |
391 | |
392 q->enqueue(new SerialOldToYoungRootsTask(perm_gen, perm_top)); | |
393 | |
394 q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::universe)); | |
395 q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::jni_handles)); | |
396 // We scan the thread roots in parallel | |
397 Threads::create_thread_roots_tasks(q); | |
398 q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::object_synchronizer)); | |
399 q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::flat_profiler)); | |
400 q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::management)); | |
401 q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::system_dictionary)); | |
402 q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::jvmti)); | |
989
148e5441d916
6863023: need non-perm oops in code cache for JSR 292
jrose
parents:
579
diff
changeset
|
403 q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::code_cache)); |
0 | 404 |
405 ParallelTaskTerminator terminator( | |
1706
9d7a8ab3736b
6962589: remove breadth first scanning code from parallel gc
tonyp
parents:
1638
diff
changeset
|
406 gc_task_manager()->workers(), |
9d7a8ab3736b
6962589: remove breadth first scanning code from parallel gc
tonyp
parents:
1638
diff
changeset
|
407 (TaskQueueSetSuper*) promotion_manager->stack_array_depth()); |
0 | 408 if (ParallelGCThreads>1) { |
409 for (uint j=0; j<ParallelGCThreads; j++) { | |
410 q->enqueue(new StealTask(&terminator)); | |
411 } | |
412 } | |
413 | |
414 gc_task_manager()->execute_and_wait(q); | |
415 } | |
416 | |
417 scavenge_midpoint.update(); | |
418 | |
419 // Process reference objects discovered during scavenge | |
420 { | |
457
27a80744a83b
6778647: snap(), snap_policy() should be renamed setup(), setup_policy()
ysr
parents:
453
diff
changeset
|
421 reference_processor()->setup_policy(false); // not always_clear |
0 | 422 PSKeepAliveClosure keep_alive(promotion_manager); |
423 PSEvacuateFollowersClosure evac_followers(promotion_manager); | |
424 if (reference_processor()->processing_is_mt()) { | |
425 PSRefProcTaskExecutor task_executor; | |
426 reference_processor()->process_discovered_references( | |
453
c96030fff130
6684579: SoftReference processing can be made more efficient
ysr
parents:
269
diff
changeset
|
427 &_is_alive_closure, &keep_alive, &evac_followers, &task_executor); |
0 | 428 } else { |
429 reference_processor()->process_discovered_references( | |
453
c96030fff130
6684579: SoftReference processing can be made more efficient
ysr
parents:
269
diff
changeset
|
430 &_is_alive_closure, &keep_alive, &evac_followers, NULL); |
0 | 431 } |
432 } | |
433 | |
434 // Enqueue reference objects discovered during scavenge. | |
435 if (reference_processor()->processing_is_mt()) { | |
436 PSRefProcTaskExecutor task_executor; | |
437 reference_processor()->enqueue_discovered_references(&task_executor); | |
438 } else { | |
439 reference_processor()->enqueue_discovered_references(NULL); | |
440 } | |
441 | |
442 // Finally, flush the promotion_manager's labs, and deallocate its stacks. | |
443 PSPromotionManager::post_scavenge(); | |
444 | |
445 promotion_failure_occurred = promotion_failed(); | |
446 if (promotion_failure_occurred) { | |
447 clean_up_failed_promotion(); | |
448 if (PrintGC) { | |
449 gclog_or_tty->print("--"); | |
450 } | |
451 } | |
452 | |
453 // Let the size policy know we're done. Note that we count promotion | |
454 // failure cleanup time as part of the collection (otherwise, we're | |
455 // implicitly saying it's mutator time). | |
456 size_policy->minor_collection_end(gc_cause); | |
457 | |
458 if (!promotion_failure_occurred) { | |
459 // Swap the survivor spaces. | |
263
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
460 |
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
461 |
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
462 young_gen->eden_space()->clear(SpaceDecorator::Mangle); |
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
463 young_gen->from_space()->clear(SpaceDecorator::Mangle); |
0 | 464 young_gen->swap_spaces(); |
465 | |
466 size_t survived = young_gen->from_space()->used_in_bytes(); | |
467 size_t promoted = old_gen->used_in_bytes() - old_gen_used_before; | |
468 size_policy->update_averages(_survivor_overflow, survived, promoted); | |
469 | |
1387
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
470 // A successful scavenge should restart the GC time limit count which is |
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
471 // for full GC's. |
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
472 size_policy->reset_gc_overhead_limit_count(); |
0 | 473 if (UseAdaptiveSizePolicy) { |
474 // Calculate the new survivor size and tenuring threshold | |
475 | |
476 if (PrintAdaptiveSizePolicy) { | |
477 gclog_or_tty->print("AdaptiveSizeStart: "); | |
478 gclog_or_tty->stamp(); | |
479 gclog_or_tty->print_cr(" collection: %d ", | |
480 heap->total_collections()); | |
481 | |
482 if (Verbose) { | |
483 gclog_or_tty->print("old_gen_capacity: %d young_gen_capacity: %d" | |
484 " perm_gen_capacity: %d ", | |
485 old_gen->capacity_in_bytes(), young_gen->capacity_in_bytes(), | |
486 perm_gen->capacity_in_bytes()); | |
487 } | |
488 } | |
489 | |
490 | |
491 if (UsePerfData) { | |
492 PSGCAdaptivePolicyCounters* counters = heap->gc_policy_counters(); | |
493 counters->update_old_eden_size( | |
494 size_policy->calculated_eden_size_in_bytes()); | |
495 counters->update_old_promo_size( | |
496 size_policy->calculated_promo_size_in_bytes()); | |
497 counters->update_old_capacity(old_gen->capacity_in_bytes()); | |
498 counters->update_young_capacity(young_gen->capacity_in_bytes()); | |
499 counters->update_survived(survived); | |
500 counters->update_promoted(promoted); | |
501 counters->update_survivor_overflowed(_survivor_overflow); | |
502 } | |
503 | |
504 size_t survivor_limit = | |
505 size_policy->max_survivor_size(young_gen->max_size()); | |
506 _tenuring_threshold = | |
507 size_policy->compute_survivor_space_size_and_threshold( | |
508 _survivor_overflow, | |
509 _tenuring_threshold, | |
510 survivor_limit); | |
511 | |
512 if (PrintTenuringDistribution) { | |
513 gclog_or_tty->cr(); | |
514 gclog_or_tty->print_cr("Desired survivor size %ld bytes, new threshold %d (max %d)", | |
515 size_policy->calculated_survivor_size_in_bytes(), | |
516 _tenuring_threshold, MaxTenuringThreshold); | |
517 } | |
518 | |
519 if (UsePerfData) { | |
520 PSGCAdaptivePolicyCounters* counters = heap->gc_policy_counters(); | |
521 counters->update_tenuring_threshold(_tenuring_threshold); | |
522 counters->update_survivor_size_counters(); | |
523 } | |
524 | |
525 // Do call at minor collections? | |
526 // Don't check if the size_policy is ready at this | |
527 // level. Let the size_policy check that internally. | |
528 if (UseAdaptiveSizePolicy && | |
529 UseAdaptiveGenerationSizePolicyAtMinorCollection && | |
530 ((gc_cause != GCCause::_java_lang_system_gc) || | |
531 UseAdaptiveSizePolicyWithSystemGC)) { | |
532 | |
533 // Calculate optimial free space amounts | |
534 assert(young_gen->max_size() > | |
535 young_gen->from_space()->capacity_in_bytes() + | |
536 young_gen->to_space()->capacity_in_bytes(), | |
537 "Sizes of space in young gen are out-of-bounds"); | |
538 size_t max_eden_size = young_gen->max_size() - | |
539 young_gen->from_space()->capacity_in_bytes() - | |
540 young_gen->to_space()->capacity_in_bytes(); | |
541 size_policy->compute_generation_free_space(young_gen->used_in_bytes(), | |
542 young_gen->eden_space()->used_in_bytes(), | |
543 old_gen->used_in_bytes(), | |
544 perm_gen->used_in_bytes(), | |
545 young_gen->eden_space()->capacity_in_bytes(), | |
546 old_gen->max_gen_size(), | |
547 max_eden_size, | |
548 false /* full gc*/, | |
1387
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
549 gc_cause, |
0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
989
diff
changeset
|
550 heap->collector_policy()); |
0 | 551 |
552 } | |
553 // Resize the young generation at every collection | |
554 // even if new sizes have not been calculated. This is | |
555 // to allow resizes that may have been inhibited by the | |
556 // relative location of the "to" and "from" spaces. | |
557 | |
558 // Resizing the old gen at minor collects can cause increases | |
559 // that don't feed back to the generation sizing policy until | |
560 // a major collection. Don't resize the old gen here. | |
561 | |
562 heap->resize_young_gen(size_policy->calculated_eden_size_in_bytes(), | |
563 size_policy->calculated_survivor_size_in_bytes()); | |
564 | |
565 if (PrintAdaptiveSizePolicy) { | |
566 gclog_or_tty->print_cr("AdaptiveSizeStop: collection: %d ", | |
567 heap->total_collections()); | |
568 } | |
569 } | |
570 | |
571 // Update the structure of the eden. With NUMA-eden CPU hotplugging or offlining can | |
572 // cause the change of the heap layout. Make sure eden is reshaped if that's the case. | |
573 // Also update() will case adaptive NUMA chunk resizing. | |
574 assert(young_gen->eden_space()->is_empty(), "eden space should be empty now"); | |
575 young_gen->eden_space()->update(); | |
576 | |
577 heap->gc_policy_counters()->update_counters(); | |
578 | |
579 heap->resize_all_tlabs(); | |
580 | |
581 assert(young_gen->to_space()->is_empty(), "to space should be empty now"); | |
582 } | |
583 | |
584 COMPILER2_PRESENT(DerivedPointerTable::update_pointers()); | |
585 | |
586 NOT_PRODUCT(reference_processor()->verify_no_references_recorded()); | |
587 | |
588 // Re-verify object start arrays | |
589 if (VerifyObjectStartArray && | |
590 VerifyAfterGC) { | |
591 old_gen->verify_object_start_array(); | |
592 perm_gen->verify_object_start_array(); | |
593 } | |
594 | |
595 // Verify all old -> young cards are now precise | |
596 if (VerifyRememberedSets) { | |
597 // Precise verification will give false positives. Until this is fixed, | |
598 // use imprecise verification. | |
599 // CardTableExtension::verify_all_young_refs_precise(); | |
600 CardTableExtension::verify_all_young_refs_imprecise(); | |
601 } | |
602 | |
603 if (TraceGen0Time) accumulated_time()->stop(); | |
604 | |
605 if (PrintGC) { | |
606 if (PrintGCDetails) { | |
607 // Don't print a GC timestamp here. This is after the GC so | |
608 // would be confusing. | |
609 young_gen->print_used_change(young_gen_used_before); | |
610 } | |
611 heap->print_heap_change(prev_used); | |
612 } | |
613 | |
614 // Track memory usage and detect low memory | |
615 MemoryService::track_memory_usage(); | |
616 heap->update_counters(); | |
617 } | |
618 | |
619 if (VerifyAfterGC && heap->total_collections() >= VerifyGCStartAt) { | |
620 HandleMark hm; // Discard invalid handles created during verification | |
621 gclog_or_tty->print(" VerifyAfterGC:"); | |
622 Universe::verify(false); | |
623 } | |
624 | |
625 if (PrintHeapAtGC) { | |
626 Universe::print_heap_after_gc(); | |
627 } | |
628 | |
263
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
629 if (ZapUnusedHeapArea) { |
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
630 young_gen->eden_space()->check_mangled_unused_area_complete(); |
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
631 young_gen->from_space()->check_mangled_unused_area_complete(); |
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
632 young_gen->to_space()->check_mangled_unused_area_complete(); |
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
633 } |
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
634 |
0 | 635 scavenge_exit.update(); |
636 | |
637 if (PrintGCTaskTimeStamps) { | |
638 tty->print_cr("VM-Thread " INT64_FORMAT " " INT64_FORMAT " " INT64_FORMAT, | |
639 scavenge_entry.ticks(), scavenge_midpoint.ticks(), | |
640 scavenge_exit.ticks()); | |
641 gc_task_manager()->print_task_time_stamps(); | |
642 } | |
643 | |
546
05c6d52fa7a9
6690928: Use spinning in combination with yields for workstealing termination.
jmasa
parents:
457
diff
changeset
|
644 #ifdef TRACESPINNING |
05c6d52fa7a9
6690928: Use spinning in combination with yields for workstealing termination.
jmasa
parents:
457
diff
changeset
|
645 ParallelTaskTerminator::print_termination_counts(); |
05c6d52fa7a9
6690928: Use spinning in combination with yields for workstealing termination.
jmasa
parents:
457
diff
changeset
|
646 #endif |
05c6d52fa7a9
6690928: Use spinning in combination with yields for workstealing termination.
jmasa
parents:
457
diff
changeset
|
647 |
0 | 648 return !promotion_failure_occurred; |
649 } | |
650 | |
651 // This method iterates over all objects in the young generation, | |
652 // unforwarding markOops. It then restores any preserved mark oops, | |
653 // and clears the _preserved_mark_stack. | |
654 void PSScavenge::clean_up_failed_promotion() { | |
655 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); | |
656 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); | |
657 assert(promotion_failed(), "Sanity"); | |
658 | |
659 PSYoungGen* young_gen = heap->young_gen(); | |
660 | |
661 { | |
662 ResourceMark rm; | |
663 | |
664 // Unforward all pointers in the young gen. | |
665 PSPromotionFailedClosure unforward_closure; | |
666 young_gen->object_iterate(&unforward_closure); | |
667 | |
668 if (PrintGC && Verbose) { | |
1836
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
669 gclog_or_tty->print_cr("Restoring %d marks", _preserved_oop_stack.size()); |
0 | 670 } |
671 | |
672 // Restore any saved marks. | |
1836
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
673 while (!_preserved_oop_stack.is_empty()) { |
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
674 oop obj = _preserved_oop_stack.pop(); |
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
675 markOop mark = _preserved_mark_stack.pop(); |
0 | 676 obj->set_mark(mark); |
677 } | |
678 | |
1836
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
679 // Clear the preserved mark and oop stack caches. |
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
680 _preserved_mark_stack.clear(true); |
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
681 _preserved_oop_stack.clear(true); |
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
682 _promotion_failed = false; |
0 | 683 } |
684 | |
685 // Reset the PromotionFailureALot counters. | |
686 NOT_PRODUCT(Universe::heap()->reset_promotion_should_fail();) | |
687 } | |
688 | |
689 // This method is called whenever an attempt to promote an object | |
1836
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
690 // fails. Some markOops will need preservation, some will not. Note |
0 | 691 // that the entire eden is traversed after a failed promotion, with |
692 // all forwarded headers replaced by the default markOop. This means | |
693 // it is not neccessary to preserve most markOops. | |
694 void PSScavenge::oop_promotion_failed(oop obj, markOop obj_mark) { | |
1836
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
695 _promotion_failed = true; |
0 | 696 if (obj_mark->must_be_preserved_for_promotion_failure(obj)) { |
697 ThreadCritical tc; | |
1836
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
698 _preserved_oop_stack.push(obj); |
894b1d7c7e01
6423256: GC stacks should use a better data structure
jcoomes
parents:
1706
diff
changeset
|
699 _preserved_mark_stack.push(obj_mark); |
0 | 700 } |
701 } | |
702 | |
703 bool PSScavenge::should_attempt_scavenge() { | |
704 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); | |
705 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); | |
706 PSGCAdaptivePolicyCounters* counters = heap->gc_policy_counters(); | |
707 | |
708 if (UsePerfData) { | |
709 counters->update_scavenge_skipped(not_skipped); | |
710 } | |
711 | |
712 PSYoungGen* young_gen = heap->young_gen(); | |
713 PSOldGen* old_gen = heap->old_gen(); | |
714 | |
715 if (!ScavengeWithObjectsInToSpace) { | |
716 // Do not attempt to promote unless to_space is empty | |
717 if (!young_gen->to_space()->is_empty()) { | |
718 _consecutive_skipped_scavenges++; | |
719 if (UsePerfData) { | |
720 counters->update_scavenge_skipped(to_space_not_empty); | |
721 } | |
722 return false; | |
723 } | |
724 } | |
725 | |
726 // Test to see if the scavenge will likely fail. | |
727 PSAdaptiveSizePolicy* policy = heap->size_policy(); | |
728 | |
729 // A similar test is done in the policy's should_full_GC(). If this is | |
730 // changed, decide if that test should also be changed. | |
731 size_t avg_promoted = (size_t) policy->padded_average_promoted_in_bytes(); | |
732 size_t promotion_estimate = MIN2(avg_promoted, young_gen->used_in_bytes()); | |
733 bool result = promotion_estimate < old_gen->free_in_bytes(); | |
734 | |
735 if (PrintGCDetails && Verbose) { | |
736 gclog_or_tty->print(result ? " do scavenge: " : " skip scavenge: "); | |
737 gclog_or_tty->print_cr(" average_promoted " SIZE_FORMAT | |
738 " padded_average_promoted " SIZE_FORMAT | |
739 " free in old gen " SIZE_FORMAT, | |
740 (size_t) policy->average_promoted_in_bytes(), | |
741 (size_t) policy->padded_average_promoted_in_bytes(), | |
742 old_gen->free_in_bytes()); | |
743 if (young_gen->used_in_bytes() < | |
744 (size_t) policy->padded_average_promoted_in_bytes()) { | |
745 gclog_or_tty->print_cr(" padded_promoted_average is greater" | |
746 " than maximum promotion = " SIZE_FORMAT, young_gen->used_in_bytes()); | |
747 } | |
748 } | |
749 | |
750 if (result) { | |
751 _consecutive_skipped_scavenges = 0; | |
752 } else { | |
753 _consecutive_skipped_scavenges++; | |
754 if (UsePerfData) { | |
755 counters->update_scavenge_skipped(promoted_too_large); | |
756 } | |
757 } | |
758 return result; | |
759 } | |
760 | |
761 // Used to add tasks | |
762 GCTaskManager* const PSScavenge::gc_task_manager() { | |
763 assert(ParallelScavengeHeap::gc_task_manager() != NULL, | |
764 "shouldn't return NULL"); | |
765 return ParallelScavengeHeap::gc_task_manager(); | |
766 } | |
767 | |
768 void PSScavenge::initialize() { | |
769 // Arguments must have been parsed | |
770 | |
771 if (AlwaysTenure) { | |
772 _tenuring_threshold = 0; | |
773 } else if (NeverTenure) { | |
774 _tenuring_threshold = markOopDesc::max_age + 1; | |
775 } else { | |
776 // We want to smooth out our startup times for the AdaptiveSizePolicy | |
777 _tenuring_threshold = (UseAdaptiveSizePolicy) ? InitialTenuringThreshold : | |
778 MaxTenuringThreshold; | |
779 } | |
780 | |
781 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); | |
782 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); | |
783 | |
784 PSYoungGen* young_gen = heap->young_gen(); | |
785 PSOldGen* old_gen = heap->old_gen(); | |
786 PSPermGen* perm_gen = heap->perm_gen(); | |
787 | |
788 // Set boundary between young_gen and old_gen | |
789 assert(perm_gen->reserved().end() <= old_gen->object_space()->bottom(), | |
790 "perm above old"); | |
791 assert(old_gen->reserved().end() <= young_gen->eden_space()->bottom(), | |
792 "old above young"); | |
793 _young_generation_boundary = young_gen->eden_space()->bottom(); | |
794 | |
795 // Initialize ref handling object for scavenging. | |
796 MemRegion mr = young_gen->reserved(); | |
797 _ref_processor = ReferenceProcessor::create_ref_processor( | |
798 mr, // span | |
799 true, // atomic_discovery | |
800 true, // mt_discovery | |
801 NULL, // is_alive_non_header | |
802 ParallelGCThreads, | |
803 ParallelRefProcEnabled); | |
804 | |
805 // Cache the cardtable | |
806 BarrierSet* bs = Universe::heap()->barrier_set(); | |
807 assert(bs->kind() == BarrierSet::CardTableModRef, "Wrong barrier set kind"); | |
808 _card_table = (CardTableExtension*)bs; | |
809 | |
810 _counters = new CollectorCounters("PSScavenge", 0); | |
811 } |