51 // || |
52 // |-------------------|
53 // | |
54 // | |
55 // +-------------------+
56 //
57
58 class ChunkManager;
59 class ClassLoaderData;
60 class Metablock;
61 class Metachunk;
62 class MetaspaceTracer;
63 class MetaWord;
64 class Mutex;
65 class outputStream;
66 class PrintCLDMetaspaceInfoClosure;
67 class SpaceManager;
68 class VirtualSpaceList;
69 class CollectedHeap;
70
71 // Metaspaces each have a SpaceManager and allocations
72 // are done by the SpaceManager. Allocations are done
73 // out of the current Metachunk. When the current Metachunk
74 // is exhausted, the SpaceManager gets a new one from
75 // the current VirtualSpace. When the VirtualSpace is exhausted
76 // the SpaceManager gets a new one. The SpaceManager
77 // also manages freelists of available Chunks.
78 //
79 // Currently the space manager maintains the list of
80 // virtual spaces and the list of chunks in use. Its
81 // allocate() method returns a block for use as a
82 // quantum of metadata.
83
84 // Namespace for important central static functions
85 // (auxiliary stuff goes into MetaspaceUtils)
86 class Metaspace : public AllStatic {
87
88 friend class MetaspaceShared;
89
90 public:
91 enum MetadataType {
92 ClassType,
93 NonClassType,
94 MetadataTypeCount
95 };
96 enum MetaspaceType {
97 StandardMetaspaceType,
98 BootMetaspaceType,
99 AnonymousMetaspaceType,
100 ReflectionMetaspaceType
101 };
102
103 private:
104
105 // Align up the word size to the allocation word size
106 static size_t align_word_size_up(size_t);
107
108 // Aligned size of the metaspace.
109 static size_t _compressed_class_space_size;
110
111 static size_t compressed_class_space_size() {
112 return _compressed_class_space_size;
113 }
114
115 static void set_compressed_class_space_size(size_t size) {
116 _compressed_class_space_size = size;
117 }
118
119 static size_t _first_chunk_word_size;
120 static size_t _first_class_chunk_word_size;
176 #endif
177
178 public:
179
180 static void ergo_initialize();
181 static void global_initialize();
182 static void post_initialize();
183
184 static void verify_global_initialization();
185
186 static size_t first_chunk_word_size() { return _first_chunk_word_size; }
187 static size_t first_class_chunk_word_size() { return _first_class_chunk_word_size; }
188
189 static size_t reserve_alignment() { return _reserve_alignment; }
190 static size_t reserve_alignment_words() { return _reserve_alignment / BytesPerWord; }
191 static size_t commit_alignment() { return _commit_alignment; }
192 static size_t commit_alignment_words() { return _commit_alignment / BytesPerWord; }
193
194 static MetaWord* allocate(ClassLoaderData* loader_data, size_t word_size,
195 MetaspaceObj::Type type, TRAPS);
196 void deallocate(MetaWord* ptr, size_t byte_size, bool is_class);
197
198 static bool contains(const void* ptr);
199 static bool contains_non_shared(const void* ptr);
200
201 // Free empty virtualspaces
202 static void purge(MetadataType mdtype);
203 static void purge();
204
205 static void report_metadata_oome(ClassLoaderData* loader_data, size_t word_size,
206 MetaspaceObj::Type type, MetadataType mdtype, TRAPS);
207
208 static const char* metadata_type_name(Metaspace::MetadataType mdtype);
209
210 static void print_compressed_class_space(outputStream* st, const char* requested_addr = 0) NOT_LP64({});
211
212 // Return TRUE only if UseCompressedClassPointers is True.
213 static bool using_class_space() {
214 return NOT_LP64(false) LP64_ONLY(UseCompressedClassPointers);
215 }
216
221 };
222
223 // Manages the metaspace portion belonging to a class loader
224 class ClassLoaderMetaspace : public CHeapObj<mtClass> {
225 friend class CollectedHeap; // For expand_and_allocate()
226 friend class Metaspace;
227 friend class MetaspaceUtils;
228 friend class PrintCLDMetaspaceInfoClosure;
229 friend class VM_CollectForMetadataAllocation; // For expand_and_allocate()
230
231 private:
232
233 void initialize(Mutex* lock, Metaspace::MetaspaceType type);
234
235 // Initialize the first chunk for a Metaspace. Used for
236 // special cases such as the boot class loader, reflection
237 // class loader and anonymous class loader.
238 void initialize_first_chunk(Metaspace::MetaspaceType type, Metaspace::MetadataType mdtype);
239 Metachunk* get_initialization_chunk(Metaspace::MetaspaceType type, Metaspace::MetadataType mdtype);
240
241 SpaceManager* _vsm;
242 SpaceManager* vsm() const { return _vsm; }
243
244 SpaceManager* _class_vsm;
245 SpaceManager* class_vsm() const { return _class_vsm; }
246 SpaceManager* get_space_manager(Metaspace::MetadataType mdtype) {
247 assert(mdtype != Metaspace::MetadataTypeCount, "MetadaTypeCount can't be used as mdtype");
248 return mdtype == Metaspace::ClassType ? class_vsm() : vsm();
249 }
250
251 MetaWord* expand_and_allocate(size_t size, Metaspace::MetadataType mdtype);
252
253 size_t class_chunk_size(size_t word_size);
254
255 public:
256
257 ClassLoaderMetaspace(Mutex* lock, Metaspace::MetaspaceType type);
258 ~ClassLoaderMetaspace();
259
260 // Allocate space for metadata of type mdtype. This is space
261 // within a Metachunk and is used by
262 // allocate(ClassLoaderData*, size_t, bool, MetadataType, TRAPS)
263 MetaWord* allocate(size_t word_size, Metaspace::MetadataType mdtype);
264
265 size_t used_words_slow(Metaspace::MetadataType mdtype) const;
266 size_t free_words_slow(Metaspace::MetadataType mdtype) const;
267 size_t capacity_words_slow(Metaspace::MetadataType mdtype) const;
268
269 size_t used_bytes_slow(Metaspace::MetadataType mdtype) const;
270 size_t capacity_bytes_slow(Metaspace::MetadataType mdtype) const;
271
272 size_t allocated_blocks_bytes() const;
273 size_t allocated_chunks_bytes() const;
274
275 void deallocate(MetaWord* ptr, size_t byte_size, bool is_class);
276
277 void dump(outputStream* const out) const;
278
279 void print_on(outputStream* st) const;
280 // Debugging support
281 void verify();
282
283 }; // ClassLoaderMetaspace
284
285
286 class MetaspaceUtils : AllStatic {
287 static size_t free_chunks_total_words(Metaspace::MetadataType mdtype);
288
289 // These methods iterate over the classloader data graph
290 // for the given Metaspace type. These are slow.
291 static size_t used_bytes_slow(Metaspace::MetadataType mdtype);
292 static size_t free_bytes_slow(Metaspace::MetadataType mdtype);
293 static size_t capacity_bytes_slow(Metaspace::MetadataType mdtype);
294 static size_t capacity_bytes_slow();
295
296 // Running sum of space in all Metachunks that has been
297 // allocated to a Metaspace. This is used instead of
298 // iterating over all the classloaders. One for each
299 // type of Metadata
300 static size_t _capacity_words[Metaspace:: MetadataTypeCount];
301 // Running sum of space in all Metachunks that
302 // are being used for metadata. One for each
303 // type of Metadata.
304 static volatile size_t _used_words[Metaspace:: MetadataTypeCount];
305
306 public:
307 // Decrement and increment _allocated_capacity_words
308 static void dec_capacity(Metaspace::MetadataType type, size_t words);
309 static void inc_capacity(Metaspace::MetadataType type, size_t words);
310
311 // Decrement and increment _allocated_used_words
312 static void dec_used(Metaspace::MetadataType type, size_t words);
313 static void inc_used(Metaspace::MetadataType type, size_t words);
314
315 // Total of space allocated to metadata in all Metaspaces.
316 // This sums the space used in each Metachunk by
317 // iterating over the classloader data graph
318 static size_t used_bytes_slow() {
319 return used_bytes_slow(Metaspace::ClassType) +
320 used_bytes_slow(Metaspace::NonClassType);
321 }
322
323 // Used by MetaspaceCounters
324 static size_t free_chunks_total_words();
325 static size_t free_chunks_total_bytes();
326 static size_t free_chunks_total_bytes(Metaspace::MetadataType mdtype);
327
328 static size_t capacity_words(Metaspace::MetadataType mdtype) {
329 return _capacity_words[mdtype];
330 }
331 static size_t capacity_words() {
332 return capacity_words(Metaspace::NonClassType) +
333 capacity_words(Metaspace::ClassType);
334 }
335 static size_t capacity_bytes(Metaspace::MetadataType mdtype) {
336 return capacity_words(mdtype) * BytesPerWord;
337 }
338 static size_t capacity_bytes() {
339 return capacity_words() * BytesPerWord;
340 }
341
342 static size_t used_words(Metaspace::MetadataType mdtype) {
343 return _used_words[mdtype];
344 }
345 static size_t used_words() {
346 return used_words(Metaspace::NonClassType) +
347 used_words(Metaspace::ClassType);
348 }
349 static size_t used_bytes(Metaspace::MetadataType mdtype) {
350 return used_words(mdtype) * BytesPerWord;
351 }
352 static size_t used_bytes() {
353 return used_words() * BytesPerWord;
354 }
355
356 static size_t free_bytes();
357 static size_t free_bytes(Metaspace::MetadataType mdtype);
358
359 static size_t reserved_bytes(Metaspace::MetadataType mdtype);
360 static size_t reserved_bytes() {
361 return reserved_bytes(Metaspace::ClassType) +
362 reserved_bytes(Metaspace::NonClassType);
363 }
364
365 static size_t committed_bytes(Metaspace::MetadataType mdtype);
366 static size_t committed_bytes() {
367 return committed_bytes(Metaspace::ClassType) +
368 committed_bytes(Metaspace::NonClassType);
369 }
370
371 static size_t min_chunk_size_words();
372 static size_t min_chunk_size_bytes() {
373 return min_chunk_size_words() * BytesPerWord;
374 }
375
376 static void print_metadata_for_nmt(outputStream* out, size_t scale = K);
377
378 static bool has_chunk_free_list(Metaspace::MetadataType mdtype);
379 static MetaspaceChunkFreeListSummary chunk_free_list_summary(Metaspace::MetadataType mdtype);
380
381 // Print change in used metadata.
382 static void print_metaspace_change(size_t prev_metadata_used);
383 static void print_on(outputStream * out);
384 static void print_on(outputStream * out, Metaspace::MetadataType mdtype);
385
386 static void print_class_waste(outputStream* out);
387 static void print_waste(outputStream* out);
388
389 // Prints an ASCII representation of the given space.
390 static void print_metaspace_map(outputStream* out, Metaspace::MetadataType mdtype);
391
392 static void dump(outputStream* out);
393 static void verify_free_chunks();
394 // Checks that the values returned by allocated_capacity_bytes() and
395 // capacity_bytes_slow() are the same.
396 static void verify_capacity();
397 static void verify_used();
398 static void verify_metrics();
399 };
400
401 // Metaspace are deallocated when their class loader are GC'ed.
402 // This class implements a policy for inducing GC's to recover
403 // Metaspaces.
404
405 class MetaspaceGC : AllStatic {
406
407 // The current high-water-mark for inducing a GC.
408 // When committed memory of all metaspaces reaches this value,
409 // a GC is induced and the value is increased. Size is in bytes.
410 static volatile intptr_t _capacity_until_GC;
411
412 // For a CMS collection, signal that a concurrent collection should
413 // be started.
414 static bool _should_concurrent_collect;
415
416 static uint _shrink_factor;
417
|
51 // || |
52 // |-------------------|
53 // | |
54 // | |
55 // +-------------------+
56 //
57
58 class ChunkManager;
59 class ClassLoaderData;
60 class Metablock;
61 class Metachunk;
62 class MetaspaceTracer;
63 class MetaWord;
64 class Mutex;
65 class outputStream;
66 class PrintCLDMetaspaceInfoClosure;
67 class SpaceManager;
68 class VirtualSpaceList;
69 class CollectedHeap;
70
71 namespace metaspace {
72 namespace internals {
73 class ClassLoaderMetaspaceStatistics;
74 }}
75
76 // Metaspaces each have a SpaceManager and allocations
77 // are done by the SpaceManager. Allocations are done
78 // out of the current Metachunk. When the current Metachunk
79 // is exhausted, the SpaceManager gets a new one from
80 // the current VirtualSpace. When the VirtualSpace is exhausted
81 // the SpaceManager gets a new one. The SpaceManager
82 // also manages freelists of available Chunks.
83 //
84 // Currently the space manager maintains the list of
85 // virtual spaces and the list of chunks in use. Its
86 // allocate() method returns a block for use as a
87 // quantum of metadata.
88
89 // Namespace for important central static functions
90 // (auxiliary stuff goes into MetaspaceUtils)
91 class Metaspace : public AllStatic {
92
93 friend class MetaspaceShared;
94
95 public:
96 enum MetadataType {
97 ClassType,
98 NonClassType,
99 MetadataTypeCount
100 };
101 enum MetaspaceType {
102 ZeroMetaspaceType = 0,
103 //...
104 StandardMetaspaceType = ZeroMetaspaceType,
105 BootMetaspaceType = StandardMetaspaceType + 1,
106 AnonymousMetaspaceType = BootMetaspaceType + 1,
107 ReflectionMetaspaceType = AnonymousMetaspaceType + 1,
108 //..
109 MetaspaceTypeCount
110 };
111
112 private:
113
114 // Align up the word size to the allocation word size
115 static size_t align_word_size_up(size_t);
116
117 // Aligned size of the metaspace.
118 static size_t _compressed_class_space_size;
119
120 static size_t compressed_class_space_size() {
121 return _compressed_class_space_size;
122 }
123
124 static void set_compressed_class_space_size(size_t size) {
125 _compressed_class_space_size = size;
126 }
127
128 static size_t _first_chunk_word_size;
129 static size_t _first_class_chunk_word_size;
185 #endif
186
187 public:
188
189 static void ergo_initialize();
190 static void global_initialize();
191 static void post_initialize();
192
193 static void verify_global_initialization();
194
195 static size_t first_chunk_word_size() { return _first_chunk_word_size; }
196 static size_t first_class_chunk_word_size() { return _first_class_chunk_word_size; }
197
198 static size_t reserve_alignment() { return _reserve_alignment; }
199 static size_t reserve_alignment_words() { return _reserve_alignment / BytesPerWord; }
200 static size_t commit_alignment() { return _commit_alignment; }
201 static size_t commit_alignment_words() { return _commit_alignment / BytesPerWord; }
202
203 static MetaWord* allocate(ClassLoaderData* loader_data, size_t word_size,
204 MetaspaceObj::Type type, TRAPS);
205
206 static bool contains(const void* ptr);
207 static bool contains_non_shared(const void* ptr);
208
209 // Free empty virtualspaces
210 static void purge(MetadataType mdtype);
211 static void purge();
212
213 static void report_metadata_oome(ClassLoaderData* loader_data, size_t word_size,
214 MetaspaceObj::Type type, MetadataType mdtype, TRAPS);
215
216 static const char* metadata_type_name(Metaspace::MetadataType mdtype);
217
218 static void print_compressed_class_space(outputStream* st, const char* requested_addr = 0) NOT_LP64({});
219
220 // Return TRUE only if UseCompressedClassPointers is True.
221 static bool using_class_space() {
222 return NOT_LP64(false) LP64_ONLY(UseCompressedClassPointers);
223 }
224
229 };
230
231 // Manages the metaspace portion belonging to a class loader
232 class ClassLoaderMetaspace : public CHeapObj<mtClass> {
233 friend class CollectedHeap; // For expand_and_allocate()
234 friend class Metaspace;
235 friend class MetaspaceUtils;
236 friend class PrintCLDMetaspaceInfoClosure;
237 friend class VM_CollectForMetadataAllocation; // For expand_and_allocate()
238
239 private:
240
241 void initialize(Mutex* lock, Metaspace::MetaspaceType type);
242
243 // Initialize the first chunk for a Metaspace. Used for
244 // special cases such as the boot class loader, reflection
245 // class loader and anonymous class loader.
246 void initialize_first_chunk(Metaspace::MetaspaceType type, Metaspace::MetadataType mdtype);
247 Metachunk* get_initialization_chunk(Metaspace::MetaspaceType type, Metaspace::MetadataType mdtype);
248
249 const Metaspace::MetaspaceType _space_type;
250 Mutex* const _lock;
251 SpaceManager* _vsm;
252 SpaceManager* _class_vsm;
253
254 SpaceManager* vsm() const { return _vsm; }
255 SpaceManager* class_vsm() const { return _class_vsm; }
256 SpaceManager* get_space_manager(Metaspace::MetadataType mdtype) {
257 assert(mdtype != Metaspace::MetadataTypeCount, "MetadaTypeCount can't be used as mdtype");
258 return mdtype == Metaspace::ClassType ? class_vsm() : vsm();
259 }
260
261 Mutex* lock() const { return _lock; }
262
263 MetaWord* expand_and_allocate(size_t size, Metaspace::MetadataType mdtype);
264
265 size_t class_chunk_size(size_t word_size);
266
267 // Adds to the given statistic object. Must be locked with CLD metaspace lock.
268 void add_to_statistics_locked(metaspace::internals::ClassLoaderMetaspaceStatistics* out) const;
269
270 public:
271
272 ClassLoaderMetaspace(Mutex* lock, Metaspace::MetaspaceType type);
273 ~ClassLoaderMetaspace();
274
275 Metaspace::MetaspaceType space_type() const { return _space_type; }
276
277 // Allocate space for metadata of type mdtype. This is space
278 // within a Metachunk and is used by
279 // allocate(ClassLoaderData*, size_t, bool, MetadataType, TRAPS)
280 MetaWord* allocate(size_t word_size, Metaspace::MetadataType mdtype);
281
282 size_t allocated_blocks_bytes() const;
283 size_t allocated_chunks_bytes() const;
284
285 void deallocate(MetaWord* ptr, size_t byte_size, bool is_class);
286
287 void print_on(outputStream* st) const;
288 // Debugging support
289 void verify();
290
291 // Adds to the given statistic object. Will lock with CLD metaspace lock.
292 void add_to_statistics(metaspace::internals::ClassLoaderMetaspaceStatistics* out) const;
293
294 }; // ClassLoaderMetaspace
295
296 class MetaspaceUtils : AllStatic {
297
298 // Spacemanager updates running counters.
299 friend class SpaceManager;
300
301 // Running counters for statistics concerning in-use chunks.
302 // Note: capacity = used + free + waste + overhead. Note that we do not
303 // count free and waste. Their sum can be deduces from the three other values.
304 // For more details, one should call print_report() from within a safe point.
305 static size_t _capacity_words [Metaspace:: MetadataTypeCount];
306 static size_t _overhead_words [Metaspace:: MetadataTypeCount];
307 static volatile size_t _used_words [Metaspace:: MetadataTypeCount];
308
309 // Atomically decrement or increment in-use statistic counters
310 static void dec_capacity(Metaspace::MetadataType mdtype, size_t words);
311 static void inc_capacity(Metaspace::MetadataType mdtype, size_t words);
312 static void dec_used(Metaspace::MetadataType mdtype, size_t words);
313 static void inc_used(Metaspace::MetadataType mdtype, size_t words);
314 static void dec_overhead(Metaspace::MetadataType mdtype, size_t words);
315 static void inc_overhead(Metaspace::MetadataType mdtype, size_t words);
316
317
318 // Getters for the in-use counters.
319 static size_t capacity_words(Metaspace::MetadataType mdtype) { return _capacity_words[mdtype]; }
320 static size_t used_words(Metaspace::MetadataType mdtype) { return _used_words[mdtype]; }
321 static size_t overhead_words(Metaspace::MetadataType mdtype) { return _overhead_words[mdtype]; }
322
323 static size_t free_chunks_total_words(Metaspace::MetadataType mdtype);
324
325 // Helper for print_xx_report.
326 static void print_vs(outputStream* out, size_t scale);
327
328 public:
329
330 // Collect used metaspace statistics. This involves walking the CLDG. The resulting
331 // output will be the accumulated values for all live metaspaces.
332 // Note: method does not do any locking.
333 static void collect_statistics(metaspace::internals::ClassLoaderMetaspaceStatistics* out);
334
335 // Used by MetaspaceCounters
336 static size_t free_chunks_total_words();
337 static size_t free_chunks_total_bytes();
338 static size_t free_chunks_total_bytes(Metaspace::MetadataType mdtype);
339
340 static size_t capacity_words() {
341 return capacity_words(Metaspace::NonClassType) +
342 capacity_words(Metaspace::ClassType);
343 }
344 static size_t capacity_bytes(Metaspace::MetadataType mdtype) {
345 return capacity_words(mdtype) * BytesPerWord;
346 }
347 static size_t capacity_bytes() {
348 return capacity_words() * BytesPerWord;
349 }
350
351 static size_t used_words() {
352 return used_words(Metaspace::NonClassType) +
353 used_words(Metaspace::ClassType);
354 }
355 static size_t used_bytes(Metaspace::MetadataType mdtype) {
356 return used_words(mdtype) * BytesPerWord;
357 }
358 static size_t used_bytes() {
359 return used_words() * BytesPerWord;
360 }
361
362 // Space committed but yet unclaimed by any class loader.
363 static size_t free_in_vs_bytes();
364 static size_t free_in_vs_bytes(Metaspace::MetadataType mdtype);
365
366 static size_t reserved_bytes(Metaspace::MetadataType mdtype);
367 static size_t reserved_bytes() {
368 return reserved_bytes(Metaspace::ClassType) +
369 reserved_bytes(Metaspace::NonClassType);
370 }
371
372 static size_t committed_bytes(Metaspace::MetadataType mdtype);
373 static size_t committed_bytes() {
374 return committed_bytes(Metaspace::ClassType) +
375 committed_bytes(Metaspace::NonClassType);
376 }
377
378 static size_t min_chunk_size_words();
379 static size_t min_chunk_size_bytes() {
380 return min_chunk_size_words() * BytesPerWord;
381 }
382
383 // Flags for print_report().
384 enum ReportFlag {
385 // Show usage by class loader.
386 rf_show_loaders = (1 << 0),
387 // Breaks report down by chunk type (small, medium, ...).
388 rf_break_down_by_chunktype = (1 << 1),
389 // Breaks report down by space type (anonymous, reflection, ...).
390 rf_break_down_by_spacetype = (1 << 2),
391 // Print details about the underlying virtual spaces.
392 rf_show_vslist = (1 << 3),
393 // Print metaspace map.
394 rf_show_vsmap = (1 << 4)
395 };
396
397 // This will print out a basic metaspace usage report but
398 // unlike print_report() is guaranteed not to lock or to walk the CLDG.
399 static void print_basic_report(outputStream* st, size_t scale);
400
401 // Prints a report about the current metaspace state.
402 // Optional parts can be enabled via flags.
403 // Function will walk the CLDG and will lock the expand lock; if that is not
404 // convenient, use print_basic_report() instead.
405 static void print_report(outputStream* out, size_t scale = 0, int flags = 0);
406
407 static bool has_chunk_free_list(Metaspace::MetadataType mdtype);
408 static MetaspaceChunkFreeListSummary chunk_free_list_summary(Metaspace::MetadataType mdtype);
409
410 // Print change in used metadata.
411 static void print_metaspace_change(size_t prev_metadata_used);
412 static void print_on(outputStream * out);
413
414 // Prints an ASCII representation of the given space.
415 static void print_metaspace_map(outputStream* out, Metaspace::MetadataType mdtype);
416
417 static void dump(outputStream* out);
418 static void verify_free_chunks();
419 // Check internal counters (capacity, used).
420 static void verify_metrics();
421 };
422
423 // Metaspace are deallocated when their class loader are GC'ed.
424 // This class implements a policy for inducing GC's to recover
425 // Metaspaces.
426
427 class MetaspaceGC : AllStatic {
428
429 // The current high-water-mark for inducing a GC.
430 // When committed memory of all metaspaces reaches this value,
431 // a GC is induced and the value is increased. Size is in bytes.
432 static volatile intptr_t _capacity_until_GC;
433
434 // For a CMS collection, signal that a concurrent collection should
435 // be started.
436 static bool _should_concurrent_collect;
437
438 static uint _shrink_factor;
439
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