1 /*
2 * Copyright (c) 2001, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
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23 */
24
25 #ifndef SHARE_VM_GC_PARALLEL_PARALLELSCAVENGEHEAP_HPP
26 #define SHARE_VM_GC_PARALLEL_PARALLELSCAVENGEHEAP_HPP
27
28 #include "gc/parallel/objectStartArray.hpp"
29 #include "gc/parallel/psGCAdaptivePolicyCounters.hpp"
30 #include "gc/parallel/psOldGen.hpp"
31 #include "gc/parallel/psSettings.hpp"
32 #include "gc/parallel/psYoungGen.hpp"
33 #include "gc/shared/collectedHeap.hpp"
34 #include "gc/shared/gcPolicyCounters.hpp"
35 #include "gc/shared/gcWhen.hpp"
36 #include "gc/shared/softRefPolicy.hpp"
37 #include "gc/shared/strongRootsScope.hpp"
38 #include "memory/metaspace.hpp"
39 #include "utilities/growableArray.hpp"
40 #include "utilities/ostream.hpp"
41
42 class AdjoiningGenerations;
43 class GCHeapSummary;
44 class GCTaskManager;
45 class MemoryManager;
46 class MemoryPool;
47 class PSAdaptiveSizePolicy;
48 class PSGCAdaptivePolicyCounters;
49 class PSHeapSummary;
50
51 class ParallelScavengeHeap : public CollectedHeap {
52 friend class VMStructs;
53 private:
54 static PSYoungGen* _young_gen;
55 static PSOldGen* _old_gen;
56
57 // Sizing policy for entire heap
58 static PSAdaptiveSizePolicy* _size_policy;
59 static PSGCAdaptivePolicyCounters* _gc_policy_counters;
60
61 const PSSettings _settings;
62
63 SoftRefPolicy _soft_ref_policy;
64
65 // Collection of generations that are adjacent in the
66 // space reserved for the heap.
67 AdjoiningGenerations* _gens;
68 unsigned int _death_march_count;
69
70 // The task manager
71 static GCTaskManager* _gc_task_manager;
72
73 GCMemoryManager* _young_manager;
74 GCMemoryManager* _old_manager;
75
76 MemoryPool* _eden_pool;
77 MemoryPool* _survivor_pool;
78 MemoryPool* _old_pool;
79
80 virtual void initialize_serviceability();
81
82 void trace_heap(GCWhen::Type when, const GCTracer* tracer);
83
84 protected:
85 static inline size_t total_invocations();
86 HeapWord* allocate_new_tlab(size_t size);
87
88 inline bool should_alloc_in_eden(size_t size) const;
89 inline void death_march_check(HeapWord* const result, size_t size);
90 HeapWord* mem_allocate_old_gen(size_t size);
91
92 public:
93 ParallelScavengeHeap(const PSSettings& settings) :
94 CollectedHeap(),
95 _settings(settings),
96 _death_march_count(0) { }
97
98 // For use by VM operations
99 enum CollectionType {
100 Scavenge,
101 MarkSweep
102 };
103
104 virtual Name kind() const {
105 return CollectedHeap::ParallelScavengeHeap;
106 }
107
108 virtual const char* name() const {
109 return "Parallel";
110 }
111
112 virtual SoftRefPolicy* soft_ref_policy() { return &_soft_ref_policy; }
113
114 virtual GrowableArray<GCMemoryManager*> memory_managers();
115 virtual GrowableArray<MemoryPool*> memory_pools();
116
117 static PSYoungGen* young_gen() { return _young_gen; }
118 static PSOldGen* old_gen() { return _old_gen; }
119
120 virtual PSAdaptiveSizePolicy* size_policy() { return _size_policy; }
121
122 static PSGCAdaptivePolicyCounters* gc_policy_counters() { return _gc_policy_counters; }
123
124 static ParallelScavengeHeap* heap();
125
126 static GCTaskManager* const gc_task_manager() { return _gc_task_manager; }
127
128 AdjoiningGenerations* gens() { return _gens; }
129
130 // Returns JNI_OK on success
131 virtual jint initialize();
132
133 void post_initialize();
134 void update_counters();
135
136 // The alignment used for the various areas
137 size_t gen_alignment() const { return _settings._gen_alignment; }
138 size_t space_alignment() const { return _settings._space_alignment; }
139 size_t heap_alignment() const { return _settings._heap_alignment; }
140
141 // Return the (conservative) maximum heap alignment
142 static size_t conservative_max_heap_alignment() {
143 return compute_heap_alignment();
144 }
145
146 size_t capacity() const;
147 size_t used() const;
148
149 // Return "true" if all generations have reached the
150 // maximal committed limit that they can reach, without a garbage
151 // collection.
152 virtual bool is_maximal_no_gc() const;
153
154 // Return true if the reference points to an object that
155 // can be moved in a partial collection. For currently implemented
156 // generational collectors that means during a collection of
157 // the young gen.
158 virtual bool is_scavengable(oop obj);
159 virtual void register_nmethod(nmethod* nm);
160 virtual void verify_nmethod(nmethod* nmethod);
161
162 size_t max_capacity() const;
163
164 // Whether p is in the allocated part of the heap
165 bool is_in(const void* p) const;
166
167 bool is_in_reserved(const void* p) const;
168
169 bool is_in_young(oop p); // reserved part
170 bool is_in_old(oop p); // reserved part
171
172 // Memory allocation. "gc_time_limit_was_exceeded" will
173 // be set to true if the adaptive size policy determine that
174 // an excessive amount of time is being spent doing collections
175 // and caused a NULL to be returned. If a NULL is not returned,
176 // "gc_time_limit_was_exceeded" has an undefined meaning.
177 HeapWord* mem_allocate(size_t size, bool* gc_overhead_limit_was_exceeded);
178
179 // Allocation attempt(s) during a safepoint. It should never be called
180 // to allocate a new TLAB as this allocation might be satisfied out
181 // of the old generation.
182 HeapWord* failed_mem_allocate(size_t size);
183
184 // Support for System.gc()
185 void collect(GCCause::Cause cause);
186
187 // These also should be called by the vm thread at a safepoint (e.g., from a
188 // VM operation).
189 //
190 // The first collects the young generation only, unless the scavenge fails; it
191 // will then attempt a full gc. The second collects the entire heap; if
192 // maximum_compaction is true, it will compact everything and clear all soft
193 // references.
194 inline void invoke_scavenge();
195
196 // Perform a full collection
197 virtual void do_full_collection(bool clear_all_soft_refs);
198
199 bool supports_inline_contig_alloc() const { return !UseNUMA; }
200
201 HeapWord* volatile* top_addr() const { return !UseNUMA ? young_gen()->top_addr() : (HeapWord* volatile*)-1; }
202 HeapWord** end_addr() const { return !UseNUMA ? young_gen()->end_addr() : (HeapWord**)-1; }
203
204 void ensure_parsability(bool retire_tlabs);
205 void accumulate_statistics_all_tlabs();
206 void resize_all_tlabs();
207
208 bool supports_tlab_allocation() const { return true; }
209
210 size_t tlab_capacity(Thread* thr) const;
211 size_t tlab_used(Thread* thr) const;
212 size_t unsafe_max_tlab_alloc(Thread* thr) const;
213
214 void object_iterate(ObjectClosure* cl);
215 void safe_object_iterate(ObjectClosure* cl) { object_iterate(cl); }
216
217 HeapWord* block_start(const void* addr) const;
218 size_t block_size(const HeapWord* addr) const;
219 bool block_is_obj(const HeapWord* addr) const;
220
221 jlong millis_since_last_gc();
222
223 void prepare_for_verify();
224 PSHeapSummary create_ps_heap_summary();
225 virtual void print_on(outputStream* st) const;
226 virtual void print_on_error(outputStream* st) const;
227 virtual void print_gc_threads_on(outputStream* st) const;
228 virtual void gc_threads_do(ThreadClosure* tc) const;
229 virtual void print_tracing_info() const;
230
231 void verify(VerifyOption option /* ignored */);
232
233 // Resize the young generation. The reserved space for the
234 // generation may be expanded in preparation for the resize.
235 void resize_young_gen(size_t eden_size, size_t survivor_size);
236
237 // Resize the old generation. The reserved space for the
238 // generation may be expanded in preparation for the resize.
239 void resize_old_gen(size_t desired_free_space);
240
241 // Save the tops of the spaces in all generations
242 void record_gen_tops_before_GC() PRODUCT_RETURN;
243
244 // Mangle the unused parts of all spaces in the heap
245 void gen_mangle_unused_area() PRODUCT_RETURN;
246
247 // Call these in sequential code around the processing of strong roots.
248 class ParStrongRootsScope : public MarkScope {
249 public:
250 ParStrongRootsScope();
251 ~ParStrongRootsScope();
252 };
253
254 GCMemoryManager* old_gc_manager() const { return _old_manager; }
255 GCMemoryManager* young_gc_manager() const { return _young_manager; }
256 };
257
258 // Simple class for storing info about the heap at the start of GC, to be used
259 // after GC for comparison/printing.
260 class PreGCValues {
261 public:
262 PreGCValues(ParallelScavengeHeap* heap) :
263 _heap_used(heap->used()),
264 _young_gen_used(heap->young_gen()->used_in_bytes()),
265 _old_gen_used(heap->old_gen()->used_in_bytes()),
266 _metadata_used(MetaspaceAux::used_bytes()) { };
267
268 size_t heap_used() const { return _heap_used; }
269 size_t young_gen_used() const { return _young_gen_used; }
270 size_t old_gen_used() const { return _old_gen_used; }
271 size_t metadata_used() const { return _metadata_used; }
272
273 private:
274 size_t _heap_used;
275 size_t _young_gen_used;
276 size_t _old_gen_used;
277 size_t _metadata_used;
278 };
279
280 // Class that can be used to print information about the
281 // adaptive size policy at intervals specified by
282 // AdaptiveSizePolicyOutputInterval. Only print information
283 // if an adaptive size policy is in use.
284 class AdaptiveSizePolicyOutput : AllStatic {
285 static bool enabled() {
286 return UseParallelGC &&
287 UseAdaptiveSizePolicy &&
288 log_is_enabled(Debug, gc, ergo);
289 }
290 public:
291 static void print() {
292 if (enabled()) {
293 ParallelScavengeHeap::heap()->size_policy()->print();
294 }
295 }
296
297 static void print(AdaptiveSizePolicy* size_policy, uint count) {
298 bool do_print =
299 enabled() &&
300 (AdaptiveSizePolicyOutputInterval > 0) &&
301 (count % AdaptiveSizePolicyOutputInterval) == 0;
302
303 if (do_print) {
304 size_policy->print();
305 }
306 }
307 };
308
309 #endif // SHARE_VM_GC_PARALLEL_PARALLELSCAVENGEHEAP_HPP