author | ysr |
Fri, 17 Dec 2010 23:41:31 -0800 | |
changeset 7658 | b970e410547a |
parent 7397 | 5b173b4ca846 |
child 8688 | 493d12ccc6db |
permissions | -rw-r--r-- |
1 | 1 |
/* |
5547
f4b087cbb361
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
5343
diff
changeset
|
2 |
* Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved. |
1 | 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 |
* |
|
5547
f4b087cbb361
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
5343
diff
changeset
|
19 |
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
f4b087cbb361
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
5343
diff
changeset
|
20 |
* or visit www.oracle.com if you need additional information or have any |
f4b087cbb361
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
5343
diff
changeset
|
21 |
* questions. |
1 | 22 |
* |
23 |
*/ |
|
24 |
||
7397 | 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" |
|
1 | 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; |
|
6762
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
63 |
Stack<markOop> PSScavenge::_preserved_mark_stack; |
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
64 |
Stack<oop> PSScavenge::_preserved_oop_stack; |
1 | 65 |
CollectorCounters* PSScavenge::_counters = NULL; |
6762
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
66 |
bool PSScavenge::_promotion_failed = false; |
1 | 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 |
||
360
21d113ecbf6a
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
1
diff
changeset
|
95 |
template <class T> void do_oop_work(T* p) { |
21d113ecbf6a
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
1
diff
changeset
|
96 |
assert (!oopDesc::is_null(*p), "expected non-null ref"); |
21d113ecbf6a
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
1
diff
changeset
|
97 |
assert ((oopDesc::load_decode_heap_oop_not_null(p))->is_oop(), |
21d113ecbf6a
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
1
diff
changeset
|
98 |
"expected an oop while scanning weak refs"); |
1 | 99 |
|
100 |
// Weak refs may be visited more than once. |
|
360
21d113ecbf6a
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
1
diff
changeset
|
101 |
if (PSScavenge::should_scavenge(p, _to_space)) { |
1 | 102 |
PSScavenge::copy_and_push_safe_barrier(_promotion_manager, p); |
103 |
} |
|
104 |
} |
|
360
21d113ecbf6a
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
1
diff
changeset
|
105 |
virtual void do_oop(oop* p) { PSKeepAliveClosure::do_oop_work(p); } |
21d113ecbf6a
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
1
diff
changeset
|
106 |
virtual void do_oop(narrowOop* p) { PSKeepAliveClosure::do_oop_work(p); } |
1 | 107 |
}; |
108 |
||
109 |
class PSEvacuateFollowersClosure: public VoidClosure { |
|
110 |
private: |
|
111 |
PSPromotionManager* _promotion_manager; |
|
112 |
public: |
|
113 |
PSEvacuateFollowersClosure(PSPromotionManager* pm) : _promotion_manager(pm) {} |
|
114 |
||
360
21d113ecbf6a
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
1
diff
changeset
|
115 |
virtual void do_void() { |
1 | 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( |
|
6248
2e661807cef0
6962589: remove breadth first scanning code from parallel gc
tonyp
parents:
5918
diff
changeset
|
187 |
ParallelScavengeHeap::gc_task_manager()->workers(), |
2e661807cef0
6962589: remove breadth first scanning code from parallel gc
tonyp
parents:
5918
diff
changeset
|
188 |
(TaskQueueSetSuper*) PSPromotionManager::stack_array_depth()); |
1 | 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! |
|
5343
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
215 |
void PSScavenge::invoke() { |
1 | 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(); |
|
5343
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
224 |
IsGCActiveMark mark; |
1 | 225 |
|
5343
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
226 |
bool scavenge_was_done = PSScavenge::invoke_no_policy(); |
1 | 227 |
|
5343
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
228 |
PSGCAdaptivePolicyCounters* counters = heap->gc_policy_counters(); |
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
229 |
if (UsePerfData) |
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
230 |
counters->update_full_follows_scavenge(0); |
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
231 |
if (!scavenge_was_done || |
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
232 |
policy->should_full_GC(heap->old_gen()->free_in_bytes())) { |
1 | 233 |
if (UsePerfData) |
5343
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
234 |
counters->update_full_follows_scavenge(full_follows_scavenge); |
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
235 |
GCCauseSetter gccs(heap, GCCause::_adaptive_size_policy); |
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
236 |
CollectorPolicy* cp = heap->collector_policy(); |
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
237 |
const bool clear_all_softrefs = cp->should_clear_all_soft_refs(); |
1 | 238 |
|
5343
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
239 |
if (UseParallelOldGC) { |
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
240 |
PSParallelCompact::invoke_no_policy(clear_all_softrefs); |
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
241 |
} else { |
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
242 |
PSMarkSweep::invoke_no_policy(clear_all_softrefs); |
1 | 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 |
||
6762
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
253 |
assert(_preserved_mark_stack.is_empty(), "should be empty"); |
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
254 |
assert(_preserved_oop_stack.is_empty(), "should be empty"); |
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
255 |
|
1 | 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 |
||
971
f0b20be4165d
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
360
diff
changeset
|
291 |
if (ZapUnusedHeapArea) { |
f0b20be4165d
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
360
diff
changeset
|
292 |
// Save information needed to minimize mangling |
f0b20be4165d
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
360
diff
changeset
|
293 |
heap->record_gen_tops_before_GC(); |
f0b20be4165d
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
360
diff
changeset
|
294 |
} |
f0b20be4165d
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
360
diff
changeset
|
295 |
|
1 | 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"); |
|
971
f0b20be4165d
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
360
diff
changeset
|
346 |
young_gen->to_space()->clear(SpaceDecorator::Mangle); |
1 | 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(); |
|
1610
5dddd195cc86
6778647: snap(), snap_policy() should be renamed setup(), setup_policy()
ysr
parents:
1606
diff
changeset
|
356 |
reference_processor()->setup_policy(false); |
1 | 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"); |
|
3908
24b55ad4c228
6863023: need non-perm oops in code cache for JSR 292
jrose
parents:
2105
diff
changeset
|
384 |
ParallelScavengeHeap::ParStrongRootsScope psrs; |
1 | 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)); |
|
3908
24b55ad4c228
6863023: need non-perm oops in code cache for JSR 292
jrose
parents:
2105
diff
changeset
|
403 |
q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::code_cache)); |
1 | 404 |
|
405 |
ParallelTaskTerminator terminator( |
|
6248
2e661807cef0
6962589: remove breadth first scanning code from parallel gc
tonyp
parents:
5918
diff
changeset
|
406 |
gc_task_manager()->workers(), |
2e661807cef0
6962589: remove breadth first scanning code from parallel gc
tonyp
parents:
5918
diff
changeset
|
407 |
(TaskQueueSetSuper*) promotion_manager->stack_array_depth()); |
1 | 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 |
{ |
|
1610
5dddd195cc86
6778647: snap(), snap_policy() should be renamed setup(), setup_policy()
ysr
parents:
1606
diff
changeset
|
421 |
reference_processor()->setup_policy(false); // not always_clear |
1 | 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( |
|
1606
dcf9714addbe
6684579: SoftReference processing can be made more efficient
ysr
parents:
977
diff
changeset
|
427 |
&_is_alive_closure, &keep_alive, &evac_followers, &task_executor); |
1 | 428 |
} else { |
429 |
reference_processor()->process_discovered_references( |
|
1606
dcf9714addbe
6684579: SoftReference processing can be made more efficient
ysr
parents:
977
diff
changeset
|
430 |
&_is_alive_closure, &keep_alive, &evac_followers, NULL); |
1 | 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. |
|
971
f0b20be4165d
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
360
diff
changeset
|
460 |
|
f0b20be4165d
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
360
diff
changeset
|
461 |
|
f0b20be4165d
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
360
diff
changeset
|
462 |
young_gen->eden_space()->clear(SpaceDecorator::Mangle); |
f0b20be4165d
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
360
diff
changeset
|
463 |
young_gen->from_space()->clear(SpaceDecorator::Mangle); |
1 | 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 |
||
5343
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
470 |
// A successful scavenge should restart the GC time limit count which is |
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
471 |
// for full GC's. |
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
472 |
size_policy->reset_gc_overhead_limit_count(); |
1 | 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*/, |
|
5343
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
549 |
gc_cause, |
95a5c4b89273
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
jmasa
parents:
3908
diff
changeset
|
550 |
heap->collector_policy()); |
1 | 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 |
||
971
f0b20be4165d
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
360
diff
changeset
|
629 |
if (ZapUnusedHeapArea) { |
f0b20be4165d
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
360
diff
changeset
|
630 |
young_gen->eden_space()->check_mangled_unused_area_complete(); |
f0b20be4165d
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
360
diff
changeset
|
631 |
young_gen->from_space()->check_mangled_unused_area_complete(); |
f0b20be4165d
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
360
diff
changeset
|
632 |
young_gen->to_space()->check_mangled_unused_area_complete(); |
f0b20be4165d
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
360
diff
changeset
|
633 |
} |
f0b20be4165d
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
360
diff
changeset
|
634 |
|
1 | 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 |
||
2010
c13462bbad17
6690928: Use spinning in combination with yields for workstealing termination.
jmasa
parents:
1610
diff
changeset
|
644 |
#ifdef TRACESPINNING |
c13462bbad17
6690928: Use spinning in combination with yields for workstealing termination.
jmasa
parents:
1610
diff
changeset
|
645 |
ParallelTaskTerminator::print_termination_counts(); |
c13462bbad17
6690928: Use spinning in combination with yields for workstealing termination.
jmasa
parents:
1610
diff
changeset
|
646 |
#endif |
c13462bbad17
6690928: Use spinning in combination with yields for workstealing termination.
jmasa
parents:
1610
diff
changeset
|
647 |
|
1 | 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) { |
|
6762
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
669 |
gclog_or_tty->print_cr("Restoring %d marks", _preserved_oop_stack.size()); |
1 | 670 |
} |
671 |
||
672 |
// Restore any saved marks. |
|
6762
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
673 |
while (!_preserved_oop_stack.is_empty()) { |
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
674 |
oop obj = _preserved_oop_stack.pop(); |
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
675 |
markOop mark = _preserved_mark_stack.pop(); |
1 | 676 |
obj->set_mark(mark); |
677 |
} |
|
678 |
||
6762
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
679 |
// Clear the preserved mark and oop stack caches. |
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
680 |
_preserved_mark_stack.clear(true); |
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
681 |
_preserved_oop_stack.clear(true); |
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
682 |
_promotion_failed = false; |
1 | 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 |
|
6762
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
690 |
// fails. Some markOops will need preservation, some will not. Note |
1 | 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) { |
|
6762
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
695 |
_promotion_failed = true; |
1 | 696 |
if (obj_mark->must_be_preserved_for_promotion_failure(obj)) { |
7658
b970e410547a
6807801: CMS: could save/restore fewer header words during scavenge
ysr
parents:
7397
diff
changeset
|
697 |
// Should use per-worker private stakcs hetre rather than |
b970e410547a
6807801: CMS: could save/restore fewer header words during scavenge
ysr
parents:
7397
diff
changeset
|
698 |
// locking a common pair of stacks. |
1 | 699 |
ThreadCritical tc; |
6762
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
700 |
_preserved_oop_stack.push(obj); |
f8d1b560700e
6423256: GC stacks should use a better data structure
jcoomes
parents:
6248
diff
changeset
|
701 |
_preserved_mark_stack.push(obj_mark); |
1 | 702 |
} |
703 |
} |
|
704 |
||
705 |
bool PSScavenge::should_attempt_scavenge() { |
|
706 |
ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); |
|
707 |
assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); |
|
708 |
PSGCAdaptivePolicyCounters* counters = heap->gc_policy_counters(); |
|
709 |
||
710 |
if (UsePerfData) { |
|
711 |
counters->update_scavenge_skipped(not_skipped); |
|
712 |
} |
|
713 |
||
714 |
PSYoungGen* young_gen = heap->young_gen(); |
|
715 |
PSOldGen* old_gen = heap->old_gen(); |
|
716 |
||
717 |
if (!ScavengeWithObjectsInToSpace) { |
|
718 |
// Do not attempt to promote unless to_space is empty |
|
719 |
if (!young_gen->to_space()->is_empty()) { |
|
720 |
_consecutive_skipped_scavenges++; |
|
721 |
if (UsePerfData) { |
|
722 |
counters->update_scavenge_skipped(to_space_not_empty); |
|
723 |
} |
|
724 |
return false; |
|
725 |
} |
|
726 |
} |
|
727 |
||
728 |
// Test to see if the scavenge will likely fail. |
|
729 |
PSAdaptiveSizePolicy* policy = heap->size_policy(); |
|
730 |
||
731 |
// A similar test is done in the policy's should_full_GC(). If this is |
|
732 |
// changed, decide if that test should also be changed. |
|
733 |
size_t avg_promoted = (size_t) policy->padded_average_promoted_in_bytes(); |
|
734 |
size_t promotion_estimate = MIN2(avg_promoted, young_gen->used_in_bytes()); |
|
735 |
bool result = promotion_estimate < old_gen->free_in_bytes(); |
|
736 |
||
737 |
if (PrintGCDetails && Verbose) { |
|
738 |
gclog_or_tty->print(result ? " do scavenge: " : " skip scavenge: "); |
|
739 |
gclog_or_tty->print_cr(" average_promoted " SIZE_FORMAT |
|
740 |
" padded_average_promoted " SIZE_FORMAT |
|
741 |
" free in old gen " SIZE_FORMAT, |
|
742 |
(size_t) policy->average_promoted_in_bytes(), |
|
743 |
(size_t) policy->padded_average_promoted_in_bytes(), |
|
744 |
old_gen->free_in_bytes()); |
|
745 |
if (young_gen->used_in_bytes() < |
|
746 |
(size_t) policy->padded_average_promoted_in_bytes()) { |
|
747 |
gclog_or_tty->print_cr(" padded_promoted_average is greater" |
|
748 |
" than maximum promotion = " SIZE_FORMAT, young_gen->used_in_bytes()); |
|
749 |
} |
|
750 |
} |
|
751 |
||
752 |
if (result) { |
|
753 |
_consecutive_skipped_scavenges = 0; |
|
754 |
} else { |
|
755 |
_consecutive_skipped_scavenges++; |
|
756 |
if (UsePerfData) { |
|
757 |
counters->update_scavenge_skipped(promoted_too_large); |
|
758 |
} |
|
759 |
} |
|
760 |
return result; |
|
761 |
} |
|
762 |
||
763 |
// Used to add tasks |
|
764 |
GCTaskManager* const PSScavenge::gc_task_manager() { |
|
765 |
assert(ParallelScavengeHeap::gc_task_manager() != NULL, |
|
766 |
"shouldn't return NULL"); |
|
767 |
return ParallelScavengeHeap::gc_task_manager(); |
|
768 |
} |
|
769 |
||
770 |
void PSScavenge::initialize() { |
|
771 |
// Arguments must have been parsed |
|
772 |
||
773 |
if (AlwaysTenure) { |
|
774 |
_tenuring_threshold = 0; |
|
775 |
} else if (NeverTenure) { |
|
776 |
_tenuring_threshold = markOopDesc::max_age + 1; |
|
777 |
} else { |
|
778 |
// We want to smooth out our startup times for the AdaptiveSizePolicy |
|
779 |
_tenuring_threshold = (UseAdaptiveSizePolicy) ? InitialTenuringThreshold : |
|
780 |
MaxTenuringThreshold; |
|
781 |
} |
|
782 |
||
783 |
ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); |
|
784 |
assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); |
|
785 |
||
786 |
PSYoungGen* young_gen = heap->young_gen(); |
|
787 |
PSOldGen* old_gen = heap->old_gen(); |
|
788 |
PSPermGen* perm_gen = heap->perm_gen(); |
|
789 |
||
790 |
// Set boundary between young_gen and old_gen |
|
791 |
assert(perm_gen->reserved().end() <= old_gen->object_space()->bottom(), |
|
792 |
"perm above old"); |
|
793 |
assert(old_gen->reserved().end() <= young_gen->eden_space()->bottom(), |
|
794 |
"old above young"); |
|
795 |
_young_generation_boundary = young_gen->eden_space()->bottom(); |
|
796 |
||
797 |
// Initialize ref handling object for scavenging. |
|
798 |
MemRegion mr = young_gen->reserved(); |
|
799 |
_ref_processor = ReferenceProcessor::create_ref_processor( |
|
800 |
mr, // span |
|
801 |
true, // atomic_discovery |
|
802 |
true, // mt_discovery |
|
803 |
NULL, // is_alive_non_header |
|
804 |
ParallelGCThreads, |
|
805 |
ParallelRefProcEnabled); |
|
806 |
||
807 |
// Cache the cardtable |
|
808 |
BarrierSet* bs = Universe::heap()->barrier_set(); |
|
809 |
assert(bs->kind() == BarrierSet::CardTableModRef, "Wrong barrier set kind"); |
|
810 |
_card_table = (CardTableExtension*)bs; |
|
811 |
||
812 |
_counters = new CollectorCounters("PSScavenge", 0); |
|
813 |
} |