| 1 | /* | 
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| 2 | * Copyright (c) 2001, 2018, Oracle and/or its affiliates. All rights reserved. | 
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| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. | 
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| 4 | * | 
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| 5 | * This code is free software; you can redistribute it and/or modify it | 
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| 6 | * under the terms of the GNU General Public License version 2 only, as | 
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| 7 | * published by the Free Software Foundation. | 
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| 8 | * | 
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| 9 | * This code is distributed in the hope that it will be useful, but WITHOUT | 
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| 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | 
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| 11 | * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License | 
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| 12 | * version 2 for more details (a copy is included in the LICENSE file that | 
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| 13 | * accompanied this code). | 
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| 14 | * | 
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| 15 | * You should have received a copy of the GNU General Public License version | 
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| 16 | * 2 along with this work; if not, write to the Free Software Foundation, | 
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| 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | 
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| 18 | * | 
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| 19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA | 
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| 20 | * or visit www.oracle.com if you need additional information or have any | 
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| 21 | * questions. | 
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| 22 | * | 
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| 23 | */ | 
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| 24 |  | 
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| 25 | #include "precompiled.hpp" | 
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| 26 | #include "code/codeCache.hpp" | 
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| 27 | #include "gc/parallel/adjoiningGenerations.hpp" | 
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| 28 | #include "gc/parallel/adjoiningGenerationsForHeteroHeap.hpp" | 
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| 29 | #include "gc/parallel/adjoiningVirtualSpaces.hpp" | 
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| 30 | #include "gc/parallel/parallelArguments.hpp" | 
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| 31 | #include "gc/parallel/gcTaskManager.hpp" | 
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| 32 | #include "gc/parallel/objectStartArray.inline.hpp" | 
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| 33 | #include "gc/parallel/parallelScavengeHeap.inline.hpp" | 
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| 34 | #include "gc/parallel/psAdaptiveSizePolicy.hpp" | 
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| 35 | #include "gc/parallel/psMarkSweepProxy.hpp" | 
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| 36 | #include "gc/parallel/psMemoryPool.hpp" | 
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| 37 | #include "gc/parallel/psParallelCompact.inline.hpp" | 
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| 38 | #include "gc/parallel/psPromotionManager.hpp" | 
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| 39 | #include "gc/parallel/psScavenge.hpp" | 
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| 40 | #include "gc/parallel/psVMOperations.hpp" | 
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| 41 | #include "gc/shared/gcHeapSummary.hpp" | 
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| 42 | #include "gc/shared/gcLocker.hpp" | 
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| 43 | #include "gc/shared/gcWhen.hpp" | 
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| 44 | #include "gc/shared/genArguments.hpp" | 
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| 45 | #include "gc/shared/scavengableNMethods.hpp" | 
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| 46 | #include "logging/log.hpp" | 
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| 47 | #include "memory/metaspaceCounters.hpp" | 
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| 48 | #include "memory/universe.hpp" | 
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| 49 | #include "oops/oop.inline.hpp" | 
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| 50 | #include "runtime/handles.inline.hpp" | 
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| 51 | #include "runtime/java.hpp" | 
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| 52 | #include "runtime/vmThread.hpp" | 
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| 53 | #include "services/memoryManager.hpp" | 
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| 54 | #include "services/memTracker.hpp" | 
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| 55 | #include "utilities/macros.hpp" | 
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| 56 | #include "utilities/vmError.hpp" | 
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| 57 |  | 
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| 58 | PSYoungGen*  ParallelScavengeHeap::_young_gen = NULL; | 
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| 59 | PSOldGen*    ParallelScavengeHeap::_old_gen = NULL; | 
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| 60 | PSAdaptiveSizePolicy* ParallelScavengeHeap::_size_policy = NULL; | 
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| 61 | PSGCAdaptivePolicyCounters* ParallelScavengeHeap::_gc_policy_counters = NULL; | 
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| 62 | GCTaskManager* ParallelScavengeHeap::_gc_task_manager = NULL; | 
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| 63 |  | 
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| 64 | jint ParallelScavengeHeap::initialize() { | 
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| 65 | const size_t reserved_heap_size = ParallelArguments::heap_reserved_size_bytes(); | 
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| 66 |  | 
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| 67 | ReservedSpace heap_rs = Universe::reserve_heap(reserved_heap_size, HeapAlignment); | 
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| 68 |  | 
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| 69 | os::trace_page_sizes( "Heap", | 
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| 70 | MinHeapSize, | 
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| 71 | reserved_heap_size, | 
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| 72 | GenAlignment, | 
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| 73 | heap_rs.base(), | 
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| 74 | heap_rs.size()); | 
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| 75 |  | 
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| 76 | initialize_reserved_region((HeapWord*)heap_rs.base(), (HeapWord*)(heap_rs.base() + heap_rs.size())); | 
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| 77 |  | 
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| 78 | PSCardTable* card_table = new PSCardTable(reserved_region()); | 
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| 79 | card_table->initialize(); | 
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| 80 | CardTableBarrierSet* const barrier_set = new CardTableBarrierSet(card_table); | 
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| 81 | barrier_set->initialize(); | 
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| 82 | BarrierSet::set_barrier_set(barrier_set); | 
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| 83 |  | 
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| 84 | // Make up the generations | 
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| 85 | // Calculate the maximum size that a generation can grow.  This | 
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| 86 | // includes growth into the other generation.  Note that the | 
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| 87 | // parameter _max_gen_size is kept as the maximum | 
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| 88 | // size of the generation as the boundaries currently stand. | 
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| 89 | // _max_gen_size is still used as that value. | 
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| 90 | double max_gc_pause_sec = ((double) MaxGCPauseMillis)/1000.0; | 
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| 91 | double max_gc_minor_pause_sec = ((double) MaxGCMinorPauseMillis)/1000.0; | 
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| 92 |  | 
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| 93 | _gens = AdjoiningGenerations::create_adjoining_generations(heap_rs); | 
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| 94 |  | 
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| 95 | _old_gen = _gens->old_gen(); | 
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| 96 | _young_gen = _gens->young_gen(); | 
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| 97 |  | 
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| 98 | const size_t eden_capacity = _young_gen->eden_space()->capacity_in_bytes(); | 
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| 99 | const size_t old_capacity = _old_gen->capacity_in_bytes(); | 
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| 100 | const size_t initial_promo_size = MIN2(eden_capacity, old_capacity); | 
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| 101 | _size_policy = | 
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| 102 | new PSAdaptiveSizePolicy(eden_capacity, | 
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| 103 | initial_promo_size, | 
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| 104 | young_gen()->to_space()->capacity_in_bytes(), | 
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| 105 | GenAlignment, | 
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| 106 | max_gc_pause_sec, | 
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| 107 | max_gc_minor_pause_sec, | 
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| 108 | GCTimeRatio | 
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| 109 | ); | 
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| 110 |  | 
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| 111 | assert(ParallelArguments::is_heterogeneous_heap() || !UseAdaptiveGCBoundary || | 
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| 112 | (old_gen()->virtual_space()->high_boundary() == | 
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| 113 | young_gen()->virtual_space()->low_boundary()), | 
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| 114 | "Boundaries must meet"); | 
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| 115 | // initialize the policy counters - 2 collectors, 2 generations | 
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| 116 | _gc_policy_counters = | 
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| 117 | new PSGCAdaptivePolicyCounters( "ParScav:MSC", 2, 2, _size_policy); | 
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| 118 |  | 
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| 119 | // Set up the GCTaskManager | 
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| 120 | _gc_task_manager = GCTaskManager::create(ParallelGCThreads); | 
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| 121 |  | 
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| 122 | if (UseParallelOldGC && !PSParallelCompact::initialize()) { | 
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| 123 | return JNI_ENOMEM; | 
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| 124 | } | 
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| 125 |  | 
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| 126 | return JNI_OK; | 
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| 127 | } | 
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| 128 |  | 
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| 129 | void ParallelScavengeHeap::initialize_serviceability() { | 
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| 130 |  | 
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| 131 | _eden_pool = new EdenMutableSpacePool(_young_gen, | 
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| 132 | _young_gen->eden_space(), | 
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| 133 | "PS Eden Space", | 
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| 134 | false /* support_usage_threshold */); | 
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| 135 |  | 
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| 136 | _survivor_pool = new SurvivorMutableSpacePool(_young_gen, | 
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| 137 | "PS Survivor Space", | 
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| 138 | false /* support_usage_threshold */); | 
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| 139 |  | 
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| 140 | _old_pool = new PSGenerationPool(_old_gen, | 
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| 141 | "PS Old Gen", | 
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| 142 | true /* support_usage_threshold */); | 
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| 143 |  | 
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| 144 | _young_manager = new GCMemoryManager( "PS Scavenge", "end of minor GC"); | 
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| 145 | _old_manager = new GCMemoryManager( "PS MarkSweep", "end of major GC"); | 
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| 146 |  | 
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| 147 | _old_manager->add_pool(_eden_pool); | 
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| 148 | _old_manager->add_pool(_survivor_pool); | 
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| 149 | _old_manager->add_pool(_old_pool); | 
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| 150 |  | 
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| 151 | _young_manager->add_pool(_eden_pool); | 
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| 152 | _young_manager->add_pool(_survivor_pool); | 
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| 153 |  | 
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| 154 | } | 
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| 155 |  | 
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| 156 | class PSIsScavengable : public BoolObjectClosure { | 
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| 157 | bool do_object_b(oop obj) { | 
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| 158 | return ParallelScavengeHeap::heap()->is_in_young(obj); | 
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| 159 | } | 
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| 160 | }; | 
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| 161 |  | 
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| 162 | static PSIsScavengable _is_scavengable; | 
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| 163 |  | 
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| 164 | void ParallelScavengeHeap::post_initialize() { | 
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| 165 | CollectedHeap::post_initialize(); | 
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| 166 | // Need to init the tenuring threshold | 
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| 167 | PSScavenge::initialize(); | 
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| 168 | if (UseParallelOldGC) { | 
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| 169 | PSParallelCompact::post_initialize(); | 
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| 170 | } else { | 
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| 171 | PSMarkSweepProxy::initialize(); | 
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| 172 | } | 
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| 173 | PSPromotionManager::initialize(); | 
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| 174 |  | 
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| 175 | ScavengableNMethods::initialize(&_is_scavengable); | 
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| 176 | } | 
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| 177 |  | 
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| 178 | void ParallelScavengeHeap::update_counters() { | 
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| 179 | young_gen()->update_counters(); | 
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| 180 | old_gen()->update_counters(); | 
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| 181 | MetaspaceCounters::update_performance_counters(); | 
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| 182 | CompressedClassSpaceCounters::update_performance_counters(); | 
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| 183 | } | 
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| 184 |  | 
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| 185 | size_t ParallelScavengeHeap::capacity() const { | 
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| 186 | size_t value = young_gen()->capacity_in_bytes() + old_gen()->capacity_in_bytes(); | 
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| 187 | return value; | 
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| 188 | } | 
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| 189 |  | 
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| 190 | size_t ParallelScavengeHeap::used() const { | 
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| 191 | size_t value = young_gen()->used_in_bytes() + old_gen()->used_in_bytes(); | 
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| 192 | return value; | 
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| 193 | } | 
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| 194 |  | 
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| 195 | bool ParallelScavengeHeap::is_maximal_no_gc() const { | 
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| 196 | return old_gen()->is_maximal_no_gc() && young_gen()->is_maximal_no_gc(); | 
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| 197 | } | 
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| 198 |  | 
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| 199 |  | 
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| 200 | size_t ParallelScavengeHeap::max_capacity() const { | 
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| 201 | size_t estimated = reserved_region().byte_size(); | 
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| 202 | if (UseAdaptiveSizePolicy) { | 
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| 203 | estimated -= _size_policy->max_survivor_size(young_gen()->max_size()); | 
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| 204 | } else { | 
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| 205 | estimated -= young_gen()->to_space()->capacity_in_bytes(); | 
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| 206 | } | 
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| 207 | return MAX2(estimated, capacity()); | 
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| 208 | } | 
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| 209 |  | 
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| 210 | bool ParallelScavengeHeap::is_in(const void* p) const { | 
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| 211 | return young_gen()->is_in(p) || old_gen()->is_in(p); | 
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| 212 | } | 
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| 213 |  | 
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| 214 | bool ParallelScavengeHeap::is_in_reserved(const void* p) const { | 
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| 215 | return young_gen()->is_in_reserved(p) || old_gen()->is_in_reserved(p); | 
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| 216 | } | 
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| 217 |  | 
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| 218 | // There are two levels of allocation policy here. | 
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| 219 | // | 
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| 220 | // When an allocation request fails, the requesting thread must invoke a VM | 
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| 221 | // operation, transfer control to the VM thread, and await the results of a | 
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| 222 | // garbage collection. That is quite expensive, and we should avoid doing it | 
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| 223 | // multiple times if possible. | 
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| 224 | // | 
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| 225 | // To accomplish this, we have a basic allocation policy, and also a | 
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| 226 | // failed allocation policy. | 
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| 227 | // | 
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| 228 | // The basic allocation policy controls how you allocate memory without | 
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| 229 | // attempting garbage collection. It is okay to grab locks and | 
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| 230 | // expand the heap, if that can be done without coming to a safepoint. | 
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| 231 | // It is likely that the basic allocation policy will not be very | 
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| 232 | // aggressive. | 
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| 233 | // | 
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| 234 | // The failed allocation policy is invoked from the VM thread after | 
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| 235 | // the basic allocation policy is unable to satisfy a mem_allocate | 
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| 236 | // request. This policy needs to cover the entire range of collection, | 
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| 237 | // heap expansion, and out-of-memory conditions. It should make every | 
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| 238 | // attempt to allocate the requested memory. | 
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| 239 |  | 
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| 240 | // Basic allocation policy. Should never be called at a safepoint, or | 
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| 241 | // from the VM thread. | 
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| 242 | // | 
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| 243 | // This method must handle cases where many mem_allocate requests fail | 
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| 244 | // simultaneously. When that happens, only one VM operation will succeed, | 
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| 245 | // and the rest will not be executed. For that reason, this method loops | 
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| 246 | // during failed allocation attempts. If the java heap becomes exhausted, | 
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| 247 | // we rely on the size_policy object to force a bail out. | 
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| 248 | HeapWord* ParallelScavengeHeap::mem_allocate( | 
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| 249 | size_t size, | 
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| 250 | bool* gc_overhead_limit_was_exceeded) { | 
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| 251 | assert(!SafepointSynchronize::is_at_safepoint(), "should not be at safepoint"); | 
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| 252 | assert(Thread::current() != (Thread*)VMThread::vm_thread(), "should not be in vm thread"); | 
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| 253 | assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); | 
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| 254 |  | 
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| 255 | // In general gc_overhead_limit_was_exceeded should be false so | 
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| 256 | // set it so here and reset it to true only if the gc time | 
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| 257 | // limit is being exceeded as checked below. | 
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| 258 | *gc_overhead_limit_was_exceeded = false; | 
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| 259 |  | 
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| 260 | HeapWord* result = young_gen()->allocate(size); | 
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| 261 |  | 
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| 262 | uint loop_count = 0; | 
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| 263 | uint gc_count = 0; | 
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| 264 | uint gclocker_stalled_count = 0; | 
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| 265 |  | 
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| 266 | while (result == NULL) { | 
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| 267 | // We don't want to have multiple collections for a single filled generation. | 
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| 268 | // To prevent this, each thread tracks the total_collections() value, and if | 
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| 269 | // the count has changed, does not do a new collection. | 
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| 270 | // | 
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| 271 | // The collection count must be read only while holding the heap lock. VM | 
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| 272 | // operations also hold the heap lock during collections. There is a lock | 
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| 273 | // contention case where thread A blocks waiting on the Heap_lock, while | 
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| 274 | // thread B is holding it doing a collection. When thread A gets the lock, | 
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| 275 | // the collection count has already changed. To prevent duplicate collections, | 
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| 276 | // The policy MUST attempt allocations during the same period it reads the | 
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| 277 | // total_collections() value! | 
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| 278 | { | 
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| 279 | MutexLocker ml(Heap_lock); | 
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| 280 | gc_count = total_collections(); | 
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| 281 |  | 
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| 282 | result = young_gen()->allocate(size); | 
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| 283 | if (result != NULL) { | 
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| 284 | return result; | 
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| 285 | } | 
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| 286 |  | 
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| 287 | // If certain conditions hold, try allocating from the old gen. | 
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| 288 | result = mem_allocate_old_gen(size); | 
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| 289 | if (result != NULL) { | 
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| 290 | return result; | 
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| 291 | } | 
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| 292 |  | 
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| 293 | if (gclocker_stalled_count > GCLockerRetryAllocationCount) { | 
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| 294 | return NULL; | 
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| 295 | } | 
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| 296 |  | 
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| 297 | // Failed to allocate without a gc. | 
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| 298 | if (GCLocker::is_active_and_needs_gc()) { | 
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| 299 | // If this thread is not in a jni critical section, we stall | 
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| 300 | // the requestor until the critical section has cleared and | 
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| 301 | // GC allowed. When the critical section clears, a GC is | 
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| 302 | // initiated by the last thread exiting the critical section; so | 
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| 303 | // we retry the allocation sequence from the beginning of the loop, | 
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| 304 | // rather than causing more, now probably unnecessary, GC attempts. | 
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| 305 | JavaThread* jthr = JavaThread::current(); | 
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| 306 | if (!jthr->in_critical()) { | 
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| 307 | MutexUnlocker mul(Heap_lock); | 
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| 308 | GCLocker::stall_until_clear(); | 
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| 309 | gclocker_stalled_count += 1; | 
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| 310 | continue; | 
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| 311 | } else { | 
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| 312 | if (CheckJNICalls) { | 
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| 313 | fatal( "Possible deadlock due to allocating while" | 
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| 314 | " in jni critical section"); | 
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| 315 | } | 
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| 316 | return NULL; | 
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| 317 | } | 
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| 318 | } | 
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| 319 | } | 
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| 320 |  | 
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| 321 | if (result == NULL) { | 
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| 322 | // Generate a VM operation | 
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| 323 | VM_ParallelGCFailedAllocation op(size, gc_count); | 
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| 324 | VMThread::execute(&op); | 
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| 325 |  | 
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| 326 | // Did the VM operation execute? If so, return the result directly. | 
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| 327 | // This prevents us from looping until time out on requests that can | 
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| 328 | // not be satisfied. | 
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| 329 | if (op.prologue_succeeded()) { | 
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| 330 | assert(is_in_or_null(op.result()), "result not in heap"); | 
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| 331 |  | 
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| 332 | // If GC was locked out during VM operation then retry allocation | 
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| 333 | // and/or stall as necessary. | 
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| 334 | if (op.gc_locked()) { | 
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| 335 | assert(op.result() == NULL, "must be NULL if gc_locked() is true"); | 
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| 336 | continue;  // retry and/or stall as necessary | 
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| 337 | } | 
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| 338 |  | 
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| 339 | // Exit the loop if the gc time limit has been exceeded. | 
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| 340 | // The allocation must have failed above ("result" guarding | 
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| 341 | // this path is NULL) and the most recent collection has exceeded the | 
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| 342 | // gc overhead limit (although enough may have been collected to | 
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| 343 | // satisfy the allocation).  Exit the loop so that an out-of-memory | 
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| 344 | // will be thrown (return a NULL ignoring the contents of | 
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| 345 | // op.result()), | 
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| 346 | // but clear gc_overhead_limit_exceeded so that the next collection | 
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| 347 | // starts with a clean slate (i.e., forgets about previous overhead | 
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| 348 | // excesses).  Fill op.result() with a filler object so that the | 
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| 349 | // heap remains parsable. | 
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| 350 | const bool limit_exceeded = size_policy()->gc_overhead_limit_exceeded(); | 
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| 351 | const bool softrefs_clear = soft_ref_policy()->all_soft_refs_clear(); | 
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| 352 |  | 
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| 353 | if (limit_exceeded && softrefs_clear) { | 
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| 354 | *gc_overhead_limit_was_exceeded = true; | 
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| 355 | size_policy()->set_gc_overhead_limit_exceeded(false); | 
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| 356 | log_trace(gc)( "ParallelScavengeHeap::mem_allocate: return NULL because gc_overhead_limit_exceeded is set"); | 
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| 357 | if (op.result() != NULL) { | 
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| 358 | CollectedHeap::fill_with_object(op.result(), size); | 
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| 359 | } | 
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| 360 | return NULL; | 
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| 361 | } | 
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| 362 |  | 
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| 363 | return op.result(); | 
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| 364 | } | 
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| 365 | } | 
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| 366 |  | 
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| 367 | // The policy object will prevent us from looping forever. If the | 
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| 368 | // time spent in gc crosses a threshold, we will bail out. | 
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| 369 | loop_count++; | 
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| 370 | if ((result == NULL) && (QueuedAllocationWarningCount > 0) && | 
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| 371 | (loop_count % QueuedAllocationWarningCount == 0)) { | 
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| 372 | log_warning(gc)( "ParallelScavengeHeap::mem_allocate retries %d times", loop_count); | 
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| 373 | log_warning(gc)( "\tsize="SIZE_FORMAT, size); | 
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| 374 | } | 
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| 375 | } | 
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| 376 |  | 
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| 377 | return result; | 
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| 378 | } | 
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| 379 |  | 
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| 380 | // A "death march" is a series of ultra-slow allocations in which a full gc is | 
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| 381 | // done before each allocation, and after the full gc the allocation still | 
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| 382 | // cannot be satisfied from the young gen.  This routine detects that condition; | 
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| 383 | // it should be called after a full gc has been done and the allocation | 
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| 384 | // attempted from the young gen. The parameter 'addr' should be the result of | 
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| 385 | // that young gen allocation attempt. | 
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| 386 | void | 
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| 387 | ParallelScavengeHeap::death_march_check(HeapWord* const addr, size_t size) { | 
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| 388 | if (addr != NULL) { | 
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| 389 | _death_march_count = 0;  // death march has ended | 
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| 390 | } else if (_death_march_count == 0) { | 
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| 391 | if (should_alloc_in_eden(size)) { | 
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| 392 | _death_march_count = 1;    // death march has started | 
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| 393 | } | 
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| 394 | } | 
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| 395 | } | 
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| 396 |  | 
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| 397 | HeapWord* ParallelScavengeHeap::mem_allocate_old_gen(size_t size) { | 
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| 398 | if (!should_alloc_in_eden(size) || GCLocker::is_active_and_needs_gc()) { | 
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| 399 | // Size is too big for eden, or gc is locked out. | 
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| 400 | return old_gen()->allocate(size); | 
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| 401 | } | 
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| 402 |  | 
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| 403 | // If a "death march" is in progress, allocate from the old gen a limited | 
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| 404 | // number of times before doing a GC. | 
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| 405 | if (_death_march_count > 0) { | 
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| 406 | if (_death_march_count < 64) { | 
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| 407 | ++_death_march_count; | 
|---|
| 408 | return old_gen()->allocate(size); | 
|---|
| 409 | } else { | 
|---|
| 410 | _death_march_count = 0; | 
|---|
| 411 | } | 
|---|
| 412 | } | 
|---|
| 413 | return NULL; | 
|---|
| 414 | } | 
|---|
| 415 |  | 
|---|
| 416 | void ParallelScavengeHeap::do_full_collection(bool clear_all_soft_refs) { | 
|---|
| 417 | if (UseParallelOldGC) { | 
|---|
| 418 | // The do_full_collection() parameter clear_all_soft_refs | 
|---|
| 419 | // is interpreted here as maximum_compaction which will | 
|---|
| 420 | // cause SoftRefs to be cleared. | 
|---|
| 421 | bool maximum_compaction = clear_all_soft_refs; | 
|---|
| 422 | PSParallelCompact::invoke(maximum_compaction); | 
|---|
| 423 | } else { | 
|---|
| 424 | PSMarkSweepProxy::invoke(clear_all_soft_refs); | 
|---|
| 425 | } | 
|---|
| 426 | } | 
|---|
| 427 |  | 
|---|
| 428 | // Failed allocation policy. Must be called from the VM thread, and | 
|---|
| 429 | // only at a safepoint! Note that this method has policy for allocation | 
|---|
| 430 | // flow, and NOT collection policy. So we do not check for gc collection | 
|---|
| 431 | // time over limit here, that is the responsibility of the heap specific | 
|---|
| 432 | // collection methods. This method decides where to attempt allocations, | 
|---|
| 433 | // and when to attempt collections, but no collection specific policy. | 
|---|
| 434 | HeapWord* ParallelScavengeHeap::failed_mem_allocate(size_t size) { | 
|---|
| 435 | assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); | 
|---|
| 436 | assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); | 
|---|
| 437 | assert(!is_gc_active(), "not reentrant"); | 
|---|
| 438 | assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); | 
|---|
| 439 |  | 
|---|
| 440 | // We assume that allocation in eden will fail unless we collect. | 
|---|
| 441 |  | 
|---|
| 442 | // First level allocation failure, scavenge and allocate in young gen. | 
|---|
| 443 | GCCauseSetter gccs(this, GCCause::_allocation_failure); | 
|---|
| 444 | const bool invoked_full_gc = PSScavenge::invoke(); | 
|---|
| 445 | HeapWord* result = young_gen()->allocate(size); | 
|---|
| 446 |  | 
|---|
| 447 | // Second level allocation failure. | 
|---|
| 448 | //   Mark sweep and allocate in young generation. | 
|---|
| 449 | if (result == NULL && !invoked_full_gc) { | 
|---|
| 450 | do_full_collection(false); | 
|---|
| 451 | result = young_gen()->allocate(size); | 
|---|
| 452 | } | 
|---|
| 453 |  | 
|---|
| 454 | death_march_check(result, size); | 
|---|
| 455 |  | 
|---|
| 456 | // Third level allocation failure. | 
|---|
| 457 | //   After mark sweep and young generation allocation failure, | 
|---|
| 458 | //   allocate in old generation. | 
|---|
| 459 | if (result == NULL) { | 
|---|
| 460 | result = old_gen()->allocate(size); | 
|---|
| 461 | } | 
|---|
| 462 |  | 
|---|
| 463 | // Fourth level allocation failure. We're running out of memory. | 
|---|
| 464 | //   More complete mark sweep and allocate in young generation. | 
|---|
| 465 | if (result == NULL) { | 
|---|
| 466 | do_full_collection(true); | 
|---|
| 467 | result = young_gen()->allocate(size); | 
|---|
| 468 | } | 
|---|
| 469 |  | 
|---|
| 470 | // Fifth level allocation failure. | 
|---|
| 471 | //   After more complete mark sweep, allocate in old generation. | 
|---|
| 472 | if (result == NULL) { | 
|---|
| 473 | result = old_gen()->allocate(size); | 
|---|
| 474 | } | 
|---|
| 475 |  | 
|---|
| 476 | return result; | 
|---|
| 477 | } | 
|---|
| 478 |  | 
|---|
| 479 | void ParallelScavengeHeap::ensure_parsability(bool retire_tlabs) { | 
|---|
| 480 | CollectedHeap::ensure_parsability(retire_tlabs); | 
|---|
| 481 | young_gen()->eden_space()->ensure_parsability(); | 
|---|
| 482 | } | 
|---|
| 483 |  | 
|---|
| 484 | size_t ParallelScavengeHeap::tlab_capacity(Thread* thr) const { | 
|---|
| 485 | return young_gen()->eden_space()->tlab_capacity(thr); | 
|---|
| 486 | } | 
|---|
| 487 |  | 
|---|
| 488 | size_t ParallelScavengeHeap::tlab_used(Thread* thr) const { | 
|---|
| 489 | return young_gen()->eden_space()->tlab_used(thr); | 
|---|
| 490 | } | 
|---|
| 491 |  | 
|---|
| 492 | size_t ParallelScavengeHeap::unsafe_max_tlab_alloc(Thread* thr) const { | 
|---|
| 493 | return young_gen()->eden_space()->unsafe_max_tlab_alloc(thr); | 
|---|
| 494 | } | 
|---|
| 495 |  | 
|---|
| 496 | HeapWord* ParallelScavengeHeap::allocate_new_tlab(size_t min_size, size_t requested_size, size_t* actual_size) { | 
|---|
| 497 | HeapWord* result = young_gen()->allocate(requested_size); | 
|---|
| 498 | if (result != NULL) { | 
|---|
| 499 | *actual_size = requested_size; | 
|---|
| 500 | } | 
|---|
| 501 |  | 
|---|
| 502 | return result; | 
|---|
| 503 | } | 
|---|
| 504 |  | 
|---|
| 505 | void ParallelScavengeHeap::resize_all_tlabs() { | 
|---|
| 506 | CollectedHeap::resize_all_tlabs(); | 
|---|
| 507 | } | 
|---|
| 508 |  | 
|---|
| 509 | // This method is used by System.gc() and JVMTI. | 
|---|
| 510 | void ParallelScavengeHeap::collect(GCCause::Cause cause) { | 
|---|
| 511 | assert(!Heap_lock->owned_by_self(), | 
|---|
| 512 | "this thread should not own the Heap_lock"); | 
|---|
| 513 |  | 
|---|
| 514 | uint gc_count      = 0; | 
|---|
| 515 | uint full_gc_count = 0; | 
|---|
| 516 | { | 
|---|
| 517 | MutexLocker ml(Heap_lock); | 
|---|
| 518 | // This value is guarded by the Heap_lock | 
|---|
| 519 | gc_count      = total_collections(); | 
|---|
| 520 | full_gc_count = total_full_collections(); | 
|---|
| 521 | } | 
|---|
| 522 |  | 
|---|
| 523 | VM_ParallelGCSystemGC op(gc_count, full_gc_count, cause); | 
|---|
| 524 | VMThread::execute(&op); | 
|---|
| 525 | } | 
|---|
| 526 |  | 
|---|
| 527 | void ParallelScavengeHeap::object_iterate(ObjectClosure* cl) { | 
|---|
| 528 | young_gen()->object_iterate(cl); | 
|---|
| 529 | old_gen()->object_iterate(cl); | 
|---|
| 530 | } | 
|---|
| 531 |  | 
|---|
| 532 |  | 
|---|
| 533 | HeapWord* ParallelScavengeHeap::block_start(const void* addr) const { | 
|---|
| 534 | if (young_gen()->is_in_reserved(addr)) { | 
|---|
| 535 | assert(young_gen()->is_in(addr), | 
|---|
| 536 | "addr should be in allocated part of young gen"); | 
|---|
| 537 | // called from os::print_location by find or VMError | 
|---|
| 538 | if (Debugging || VMError::fatal_error_in_progress())  return NULL; | 
|---|
| 539 | Unimplemented(); | 
|---|
| 540 | } else if (old_gen()->is_in_reserved(addr)) { | 
|---|
| 541 | assert(old_gen()->is_in(addr), | 
|---|
| 542 | "addr should be in allocated part of old gen"); | 
|---|
| 543 | return old_gen()->start_array()->object_start((HeapWord*)addr); | 
|---|
| 544 | } | 
|---|
| 545 | return 0; | 
|---|
| 546 | } | 
|---|
| 547 |  | 
|---|
| 548 | bool ParallelScavengeHeap::block_is_obj(const HeapWord* addr) const { | 
|---|
| 549 | return block_start(addr) == addr; | 
|---|
| 550 | } | 
|---|
| 551 |  | 
|---|
| 552 | jlong ParallelScavengeHeap::millis_since_last_gc() { | 
|---|
| 553 | return UseParallelOldGC ? | 
|---|
| 554 | PSParallelCompact::millis_since_last_gc() : | 
|---|
| 555 | PSMarkSweepProxy::millis_since_last_gc(); | 
|---|
| 556 | } | 
|---|
| 557 |  | 
|---|
| 558 | void ParallelScavengeHeap::prepare_for_verify() { | 
|---|
| 559 | ensure_parsability(false);  // no need to retire TLABs for verification | 
|---|
| 560 | } | 
|---|
| 561 |  | 
|---|
| 562 | PSHeapSummary ParallelScavengeHeap::create_ps_heap_summary() { | 
|---|
| 563 | PSOldGen* old = old_gen(); | 
|---|
| 564 | HeapWord* old_committed_end = (HeapWord*)old->virtual_space()->committed_high_addr(); | 
|---|
| 565 | VirtualSpaceSummary old_summary(old->reserved().start(), old_committed_end, old->reserved().end()); | 
|---|
| 566 | SpaceSummary old_space(old->reserved().start(), old_committed_end, old->used_in_bytes()); | 
|---|
| 567 |  | 
|---|
| 568 | PSYoungGen* young = young_gen(); | 
|---|
| 569 | VirtualSpaceSummary young_summary(young->reserved().start(), | 
|---|
| 570 | (HeapWord*)young->virtual_space()->committed_high_addr(), young->reserved().end()); | 
|---|
| 571 |  | 
|---|
| 572 | MutableSpace* eden = young_gen()->eden_space(); | 
|---|
| 573 | SpaceSummary eden_space(eden->bottom(), eden->end(), eden->used_in_bytes()); | 
|---|
| 574 |  | 
|---|
| 575 | MutableSpace* from = young_gen()->from_space(); | 
|---|
| 576 | SpaceSummary from_space(from->bottom(), from->end(), from->used_in_bytes()); | 
|---|
| 577 |  | 
|---|
| 578 | MutableSpace* to = young_gen()->to_space(); | 
|---|
| 579 | SpaceSummary to_space(to->bottom(), to->end(), to->used_in_bytes()); | 
|---|
| 580 |  | 
|---|
| 581 | VirtualSpaceSummary heap_summary = create_heap_space_summary(); | 
|---|
| 582 | return PSHeapSummary(heap_summary, used(), old_summary, old_space, young_summary, eden_space, from_space, to_space); | 
|---|
| 583 | } | 
|---|
| 584 |  | 
|---|
| 585 | void ParallelScavengeHeap::print_on(outputStream* st) const { | 
|---|
| 586 | young_gen()->print_on(st); | 
|---|
| 587 | old_gen()->print_on(st); | 
|---|
| 588 | MetaspaceUtils::print_on(st); | 
|---|
| 589 | } | 
|---|
| 590 |  | 
|---|
| 591 | void ParallelScavengeHeap::print_on_error(outputStream* st) const { | 
|---|
| 592 | this->CollectedHeap::print_on_error(st); | 
|---|
| 593 |  | 
|---|
| 594 | if (UseParallelOldGC) { | 
|---|
| 595 | st->cr(); | 
|---|
| 596 | PSParallelCompact::print_on_error(st); | 
|---|
| 597 | } | 
|---|
| 598 | } | 
|---|
| 599 |  | 
|---|
| 600 | void ParallelScavengeHeap::gc_threads_do(ThreadClosure* tc) const { | 
|---|
| 601 | PSScavenge::gc_task_manager()->threads_do(tc); | 
|---|
| 602 | } | 
|---|
| 603 |  | 
|---|
| 604 | void ParallelScavengeHeap::print_gc_threads_on(outputStream* st) const { | 
|---|
| 605 | PSScavenge::gc_task_manager()->print_threads_on(st); | 
|---|
| 606 | } | 
|---|
| 607 |  | 
|---|
| 608 | void ParallelScavengeHeap::print_tracing_info() const { | 
|---|
| 609 | AdaptiveSizePolicyOutput::print(); | 
|---|
| 610 | log_debug(gc, heap, exit)( "Accumulated young generation GC time %3.7f secs", PSScavenge::accumulated_time()->seconds()); | 
|---|
| 611 | log_debug(gc, heap, exit)( "Accumulated old generation GC time %3.7f secs", | 
|---|
| 612 | UseParallelOldGC ? PSParallelCompact::accumulated_time()->seconds() : PSMarkSweepProxy::accumulated_time()->seconds()); | 
|---|
| 613 | } | 
|---|
| 614 |  | 
|---|
| 615 |  | 
|---|
| 616 | void ParallelScavengeHeap::verify(VerifyOption option /* ignored */) { | 
|---|
| 617 | // Why do we need the total_collections()-filter below? | 
|---|
| 618 | if (total_collections() > 0) { | 
|---|
| 619 | log_debug(gc, verify)( "Tenured"); | 
|---|
| 620 | old_gen()->verify(); | 
|---|
| 621 |  | 
|---|
| 622 | log_debug(gc, verify)( "Eden"); | 
|---|
| 623 | young_gen()->verify(); | 
|---|
| 624 | } | 
|---|
| 625 | } | 
|---|
| 626 |  | 
|---|
| 627 | void ParallelScavengeHeap::trace_heap(GCWhen::Type when, const GCTracer* gc_tracer) { | 
|---|
| 628 | const PSHeapSummary& heap_summary = create_ps_heap_summary(); | 
|---|
| 629 | gc_tracer->report_gc_heap_summary(when, heap_summary); | 
|---|
| 630 |  | 
|---|
| 631 | const MetaspaceSummary& metaspace_summary = create_metaspace_summary(); | 
|---|
| 632 | gc_tracer->report_metaspace_summary(when, metaspace_summary); | 
|---|
| 633 | } | 
|---|
| 634 |  | 
|---|
| 635 | ParallelScavengeHeap* ParallelScavengeHeap::heap() { | 
|---|
| 636 | CollectedHeap* heap = Universe::heap(); | 
|---|
| 637 | assert(heap != NULL, "Uninitialized access to ParallelScavengeHeap::heap()"); | 
|---|
| 638 | assert(heap->kind() == CollectedHeap::Parallel, "Invalid name"); | 
|---|
| 639 | return (ParallelScavengeHeap*)heap; | 
|---|
| 640 | } | 
|---|
| 641 |  | 
|---|
| 642 | CardTableBarrierSet* ParallelScavengeHeap::barrier_set() { | 
|---|
| 643 | return barrier_set_cast<CardTableBarrierSet>(BarrierSet::barrier_set()); | 
|---|
| 644 | } | 
|---|
| 645 |  | 
|---|
| 646 | PSCardTable* ParallelScavengeHeap::card_table() { | 
|---|
| 647 | return static_cast<PSCardTable*>(barrier_set()->card_table()); | 
|---|
| 648 | } | 
|---|
| 649 |  | 
|---|
| 650 | // Before delegating the resize to the young generation, | 
|---|
| 651 | // the reserved space for the young and old generations | 
|---|
| 652 | // may be changed to accommodate the desired resize. | 
|---|
| 653 | void ParallelScavengeHeap::resize_young_gen(size_t eden_size, | 
|---|
| 654 | size_t survivor_size) { | 
|---|
| 655 | if (UseAdaptiveGCBoundary) { | 
|---|
| 656 | if (size_policy()->bytes_absorbed_from_eden() != 0) { | 
|---|
| 657 | size_policy()->reset_bytes_absorbed_from_eden(); | 
|---|
| 658 | return;  // The generation changed size already. | 
|---|
| 659 | } | 
|---|
| 660 | gens()->adjust_boundary_for_young_gen_needs(eden_size, survivor_size); | 
|---|
| 661 | } | 
|---|
| 662 |  | 
|---|
| 663 | // Delegate the resize to the generation. | 
|---|
| 664 | _young_gen->resize(eden_size, survivor_size); | 
|---|
| 665 | } | 
|---|
| 666 |  | 
|---|
| 667 | // Before delegating the resize to the old generation, | 
|---|
| 668 | // the reserved space for the young and old generations | 
|---|
| 669 | // may be changed to accommodate the desired resize. | 
|---|
| 670 | void ParallelScavengeHeap::resize_old_gen(size_t desired_free_space) { | 
|---|
| 671 | if (UseAdaptiveGCBoundary) { | 
|---|
| 672 | if (size_policy()->bytes_absorbed_from_eden() != 0) { | 
|---|
| 673 | size_policy()->reset_bytes_absorbed_from_eden(); | 
|---|
| 674 | return;  // The generation changed size already. | 
|---|
| 675 | } | 
|---|
| 676 | gens()->adjust_boundary_for_old_gen_needs(desired_free_space); | 
|---|
| 677 | } | 
|---|
| 678 |  | 
|---|
| 679 | // Delegate the resize to the generation. | 
|---|
| 680 | _old_gen->resize(desired_free_space); | 
|---|
| 681 | } | 
|---|
| 682 |  | 
|---|
| 683 | ParallelScavengeHeap::ParStrongRootsScope::ParStrongRootsScope() { | 
|---|
| 684 | // nothing particular | 
|---|
| 685 | } | 
|---|
| 686 |  | 
|---|
| 687 | ParallelScavengeHeap::ParStrongRootsScope::~ParStrongRootsScope() { | 
|---|
| 688 | // nothing particular | 
|---|
| 689 | } | 
|---|
| 690 |  | 
|---|
| 691 | #ifndef PRODUCT | 
|---|
| 692 | void ParallelScavengeHeap::record_gen_tops_before_GC() { | 
|---|
| 693 | if (ZapUnusedHeapArea) { | 
|---|
| 694 | young_gen()->record_spaces_top(); | 
|---|
| 695 | old_gen()->record_spaces_top(); | 
|---|
| 696 | } | 
|---|
| 697 | } | 
|---|
| 698 |  | 
|---|
| 699 | void ParallelScavengeHeap::gen_mangle_unused_area() { | 
|---|
| 700 | if (ZapUnusedHeapArea) { | 
|---|
| 701 | young_gen()->eden_space()->mangle_unused_area(); | 
|---|
| 702 | young_gen()->to_space()->mangle_unused_area(); | 
|---|
| 703 | young_gen()->from_space()->mangle_unused_area(); | 
|---|
| 704 | old_gen()->object_space()->mangle_unused_area(); | 
|---|
| 705 | } | 
|---|
| 706 | } | 
|---|
| 707 | #endif | 
|---|
| 708 |  | 
|---|
| 709 | void ParallelScavengeHeap::register_nmethod(nmethod* nm) { | 
|---|
| 710 | ScavengableNMethods::register_nmethod(nm); | 
|---|
| 711 | } | 
|---|
| 712 |  | 
|---|
| 713 | void ParallelScavengeHeap::unregister_nmethod(nmethod* nm) { | 
|---|
| 714 | ScavengableNMethods::unregister_nmethod(nm); | 
|---|
| 715 | } | 
|---|
| 716 |  | 
|---|
| 717 | void ParallelScavengeHeap::verify_nmethod(nmethod* nm) { | 
|---|
| 718 | ScavengableNMethods::verify_nmethod(nm); | 
|---|
| 719 | } | 
|---|
| 720 |  | 
|---|
| 721 | void ParallelScavengeHeap::flush_nmethod(nmethod* nm) { | 
|---|
| 722 | // nothing particular | 
|---|
| 723 | } | 
|---|
| 724 |  | 
|---|
| 725 | void ParallelScavengeHeap::prune_scavengable_nmethods() { | 
|---|
| 726 | ScavengableNMethods::prune_nmethods(); | 
|---|
| 727 | } | 
|---|
| 728 |  | 
|---|
| 729 | GrowableArray<GCMemoryManager*> ParallelScavengeHeap::memory_managers() { | 
|---|
| 730 | GrowableArray<GCMemoryManager*> memory_managers(2); | 
|---|
| 731 | memory_managers.append(_young_manager); | 
|---|
| 732 | memory_managers.append(_old_manager); | 
|---|
| 733 | return memory_managers; | 
|---|
| 734 | } | 
|---|
| 735 |  | 
|---|
| 736 | GrowableArray<MemoryPool*> ParallelScavengeHeap::memory_pools() { | 
|---|
| 737 | GrowableArray<MemoryPool*> memory_pools(3); | 
|---|
| 738 | memory_pools.append(_eden_pool); | 
|---|
| 739 | memory_pools.append(_survivor_pool); | 
|---|
| 740 | memory_pools.append(_old_pool); | 
|---|
| 741 | return memory_pools; | 
|---|
| 742 | } | 
|---|
| 743 |  | 
|---|