Mercurial > hg > truffle
comparison src/share/vm/memory/metaspace.hpp @ 6725:da91efe96a93
6964458: Reimplement class meta-data storage to use native memory
Summary: Remove PermGen, allocate meta-data in metaspace linked to class loaders, rewrite GC walking, rewrite and rename metadata to be C++ classes
Reviewed-by: jmasa, stefank, never, coleenp, kvn, brutisso, mgerdin, dholmes, jrose, twisti, roland
Contributed-by: jmasa <jon.masamitsu@oracle.com>, stefank <stefan.karlsson@oracle.com>, mgerdin <mikael.gerdin@oracle.com>, never <tom.rodriguez@oracle.com>
author | coleenp |
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date | Sat, 01 Sep 2012 13:25:18 -0400 |
parents | |
children | 5d2156bcb78b |
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1 /* | |
2 * Copyright (c) 2011, 2012, Oracle and/or its affiliates. All rights reserved. | |
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. | |
4 * | |
5 * This code is free software; you can redistribute it and/or modify it | |
6 * under the terms of the GNU General Public License version 2 only, as | |
7 * published by the Free Software Foundation. | |
8 * | |
9 * This code is distributed in the hope that it will be useful, but WITHOUT | |
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
12 * version 2 for more details (a copy is included in the LICENSE file that | |
13 * accompanied this code). | |
14 * | |
15 * You should have received a copy of the GNU General Public License version | |
16 * 2 along with this work; if not, write to the Free Software Foundation, | |
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | |
18 * | |
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA | |
20 * or visit www.oracle.com if you need additional information or have any | |
21 * questions. | |
22 * | |
23 */ | |
24 #ifndef SHARE_VM_MEMORY_METASPACE_HPP | |
25 #define SHARE_VM_MEMORY_METASPACE_HPP | |
26 | |
27 #include "memory/allocation.hpp" | |
28 #include "memory/memRegion.hpp" | |
29 #include "runtime/virtualspace.hpp" | |
30 #include "utilities/exceptions.hpp" | |
31 | |
32 // Metaspace | |
33 // | |
34 // Metaspaces are Arenas for the VM's metadata. | |
35 // They are allocated one per class loader object, and one for the null | |
36 // bootstrap class loader | |
37 // Eventually for bootstrap loader we'll have a read-only section and read-write | |
38 // to write for DumpSharedSpaces and read for UseSharedSpaces | |
39 // | |
40 // block X ---+ +-------------------+ | |
41 // | | Virtualspace | | |
42 // | | | | |
43 // | | | | |
44 // | |-------------------| | |
45 // | || Chunk | | |
46 // | || | | |
47 // | ||---------- | | |
48 // +------>||| block 0 | | | |
49 // ||---------- | | |
50 // ||| block 1 | | | |
51 // ||---------- | | |
52 // || | | |
53 // |-------------------| | |
54 // | | | |
55 // | | | |
56 // +-------------------+ | |
57 // | |
58 | |
59 class ClassLoaderData; | |
60 class MetaWord; | |
61 class Mutex; | |
62 class outputStream; | |
63 class FreeChunk; | |
64 template <class Chunk_t> class FreeList; | |
65 template <class Chunk_t> class BinaryTreeDictionary; | |
66 class SpaceManager; | |
67 | |
68 // Metaspaces each have a SpaceManager and allocations | |
69 // are done by the SpaceManager. Allocations are done | |
70 // out of the current Metachunk. When the current Metachunk | |
71 // is exhausted, the SpaceManager gets a new one from | |
72 // the current VirtualSpace. When the VirtualSpace is exhausted | |
73 // the SpaceManager gets a new one. The SpaceManager | |
74 // also manages freelists of available Chunks. | |
75 // | |
76 // Currently the space manager maintains the list of | |
77 // virtual spaces and the list of chunks in use. Its | |
78 // allocate() method returns a block for use as a | |
79 // quantum of metadata. | |
80 | |
81 class VirtualSpaceList; | |
82 | |
83 class Metaspace : public CHeapObj<mtClass> { | |
84 friend class VMStructs; | |
85 friend class SpaceManager; | |
86 friend class VM_CollectForMetadataAllocation; | |
87 friend class MetaspaceGC; | |
88 friend class MetaspaceAux; | |
89 | |
90 public: | |
91 enum MetadataType {ClassType, NonClassType}; | |
92 | |
93 private: | |
94 void initialize(Mutex* lock, size_t initial_size = 0); | |
95 | |
96 static size_t _first_chunk_word_size; | |
97 | |
98 SpaceManager* _vsm; | |
99 SpaceManager* vsm() const { return _vsm; } | |
100 | |
101 SpaceManager* _class_vsm; | |
102 SpaceManager* class_vsm() const { return _class_vsm; } | |
103 | |
104 MetaWord* allocate(size_t word_size, MetadataType mdtype); | |
105 | |
106 // Virtual Space lists for both classes and other metadata | |
107 static VirtualSpaceList* _space_list; | |
108 static VirtualSpaceList* _class_space_list; | |
109 | |
110 static VirtualSpaceList* space_list() { return _space_list; } | |
111 static VirtualSpaceList* class_space_list() { return _class_space_list; } | |
112 | |
113 public: | |
114 | |
115 Metaspace(Mutex* lock, size_t initial_size); | |
116 Metaspace(Mutex* lock); | |
117 ~Metaspace(); | |
118 | |
119 // Initialize globals for Metaspace | |
120 static void global_initialize(); | |
121 static void initialize_class_space(ReservedSpace rs); | |
122 | |
123 static size_t first_chunk_word_size() { return _first_chunk_word_size; } | |
124 | |
125 char* bottom() const; | |
126 size_t used_words(MetadataType mdtype) const; | |
127 size_t free_words(MetadataType mdtype) const; | |
128 size_t capacity_words(MetadataType mdtype) const; | |
129 size_t waste_words(MetadataType mdtype) const; | |
130 | |
131 static MetaWord* allocate(ClassLoaderData* loader_data, size_t size, | |
132 bool read_only, MetadataType mdtype, TRAPS); | |
133 | |
134 void deallocate(MetaWord* ptr, size_t byte_size, bool is_class); | |
135 | |
136 #ifndef PRODUCT | |
137 bool contains(const void *ptr) const; | |
138 bool contains_class(const void *ptr) const; | |
139 #endif | |
140 | |
141 void dump(outputStream* const out) const; | |
142 | |
143 void print_on(outputStream* st) const; | |
144 // Debugging support | |
145 void verify(); | |
146 }; | |
147 | |
148 class MetaspaceAux : AllStatic { | |
149 | |
150 // Statistics for class space and data space in metaspace. | |
151 static size_t used_in_bytes(Metaspace::MetadataType mdtype); | |
152 static size_t free_in_bytes(Metaspace::MetadataType mdtype); | |
153 static size_t capacity_in_bytes(Metaspace::MetadataType mdtype); | |
154 static size_t reserved_in_bytes(Metaspace::MetadataType mdtype); | |
155 | |
156 static size_t free_chunks_total(Metaspace::MetadataType mdtype); | |
157 static size_t free_chunks_total_in_bytes(Metaspace::MetadataType mdtype); | |
158 | |
159 public: | |
160 // Total of space allocated to metadata in all Metaspaces | |
161 static size_t used_in_bytes() { | |
162 return used_in_bytes(Metaspace::ClassType) + | |
163 used_in_bytes(Metaspace::NonClassType); | |
164 } | |
165 | |
166 // Total of available space in all Metaspaces | |
167 // Total of capacity allocated to all Metaspaces. This includes | |
168 // space in Metachunks not yet allocated and in the Metachunk | |
169 // freelist. | |
170 static size_t capacity_in_bytes() { | |
171 return capacity_in_bytes(Metaspace::ClassType) + | |
172 capacity_in_bytes(Metaspace::NonClassType); | |
173 } | |
174 | |
175 // Total space reserved in all Metaspaces | |
176 static size_t reserved_in_bytes() { | |
177 return reserved_in_bytes(Metaspace::ClassType) + | |
178 reserved_in_bytes(Metaspace::NonClassType); | |
179 } | |
180 | |
181 static size_t min_chunk_size(); | |
182 | |
183 // Print change in used metadata. | |
184 static void print_metaspace_change(size_t prev_metadata_used); | |
185 static void print_on(outputStream * out); | |
186 static void print_on(outputStream * out, Metaspace::MetadataType mdtype); | |
187 | |
188 static void print_waste(outputStream* out); | |
189 static void dump(outputStream* out); | |
190 }; | |
191 | |
192 // Metaspace are deallocated when their class loader are GC'ed. | |
193 // This class implements a policy for inducing GC's to recover | |
194 // Metaspaces. | |
195 | |
196 class MetaspaceGC : AllStatic { | |
197 | |
198 // The current high-water-mark for inducing a GC. When | |
199 // the capacity of all space in the virtual lists reaches this value, | |
200 // a GC is induced and the value is increased. This should be changed | |
201 // to the space actually used for allocations to avoid affects of | |
202 // fragmentation losses to partially used chunks. Size is in words. | |
203 static size_t _capacity_until_GC; | |
204 | |
205 // After a GC is done any allocation that fails should try to expand | |
206 // the capacity of the Metaspaces. This flag is set during attempts | |
207 // to allocate in the VMGCOperation that does the GC. | |
208 static bool _expand_after_GC; | |
209 | |
210 // For a CMS collection, signal that a concurrent collection should | |
211 // be started. | |
212 static bool _should_concurrent_collect; | |
213 | |
214 static uint _shrink_factor; | |
215 | |
216 static void set_capacity_until_GC(size_t v) { _capacity_until_GC = v; } | |
217 | |
218 static size_t shrink_factor() { return _shrink_factor; } | |
219 void set_shrink_factor(uint v) { _shrink_factor = v; } | |
220 | |
221 public: | |
222 | |
223 static size_t capacity_until_GC() { return _capacity_until_GC; } | |
224 static size_t capacity_until_GC_in_bytes() { return _capacity_until_GC * BytesPerWord; } | |
225 static void inc_capacity_until_GC(size_t v) { _capacity_until_GC += v; } | |
226 static void dec_capacity_until_GC(size_t v) { | |
227 _capacity_until_GC = _capacity_until_GC > v ? _capacity_until_GC - v : 0; | |
228 } | |
229 static bool expand_after_GC() { return _expand_after_GC; } | |
230 static void set_expand_after_GC(bool v) { _expand_after_GC = v; } | |
231 | |
232 static bool should_concurrent_collect() { return _should_concurrent_collect; } | |
233 static void set_should_concurrent_collect(bool v) { | |
234 _should_concurrent_collect = v; | |
235 } | |
236 | |
237 // The amount to increase the high-water-mark (_capacity_until_GC) | |
238 static size_t delta_capacity_until_GC(size_t word_size); | |
239 | |
240 // It is expected that this will be called when the current capacity | |
241 // has been used and a GC should be considered. | |
242 static bool should_expand(VirtualSpaceList* vsl, size_t word_size); | |
243 | |
244 // Calculate the new high-water mark at which to induce | |
245 // a GC. | |
246 static void compute_new_size(); | |
247 }; | |
248 | |
249 #endif // SHARE_VM_MEMORY_METASPACE_HPP |