Mon, 18 Mar 2013 09:34:58 +0100
Merge
1 /*
2 * Copyright (c) 2011, 2013, 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 #include "precompiled.hpp"
25 #include "gc_interface/collectedHeap.hpp"
26 #include "memory/binaryTreeDictionary.hpp"
27 #include "memory/freeList.hpp"
28 #include "memory/collectorPolicy.hpp"
29 #include "memory/filemap.hpp"
30 #include "memory/freeList.hpp"
31 #include "memory/metablock.hpp"
32 #include "memory/metachunk.hpp"
33 #include "memory/metaspace.hpp"
34 #include "memory/metaspaceShared.hpp"
35 #include "memory/resourceArea.hpp"
36 #include "memory/universe.hpp"
37 #include "runtime/globals.hpp"
38 #include "runtime/mutex.hpp"
39 #include "runtime/orderAccess.hpp"
40 #include "services/memTracker.hpp"
41 #include "utilities/copy.hpp"
42 #include "utilities/debug.hpp"
44 typedef BinaryTreeDictionary<Metablock, FreeList> BlockTreeDictionary;
45 typedef BinaryTreeDictionary<Metachunk, FreeList> ChunkTreeDictionary;
46 // Define this macro to enable slow integrity checking of
47 // the free chunk lists
48 const bool metaspace_slow_verify = false;
51 // Parameters for stress mode testing
52 const uint metadata_deallocate_a_lot_block = 10;
53 const uint metadata_deallocate_a_lock_chunk = 3;
54 size_t const allocation_from_dictionary_limit = 64 * K;
56 MetaWord* last_allocated = 0;
58 // Used in declarations in SpaceManager and ChunkManager
59 enum ChunkIndex {
60 ZeroIndex = 0,
61 SpecializedIndex = ZeroIndex,
62 SmallIndex = SpecializedIndex + 1,
63 MediumIndex = SmallIndex + 1,
64 HumongousIndex = MediumIndex + 1,
65 NumberOfFreeLists = 3,
66 NumberOfInUseLists = 4
67 };
69 enum ChunkSizes { // in words.
70 ClassSpecializedChunk = 128,
71 SpecializedChunk = 128,
72 ClassSmallChunk = 256,
73 SmallChunk = 512,
74 ClassMediumChunk = 1 * K,
75 MediumChunk = 8 * K,
76 HumongousChunkGranularity = 8
77 };
79 static ChunkIndex next_chunk_index(ChunkIndex i) {
80 assert(i < NumberOfInUseLists, "Out of bound");
81 return (ChunkIndex) (i+1);
82 }
84 // Originally _capacity_until_GC was set to MetaspaceSize here but
85 // the default MetaspaceSize before argument processing was being
86 // used which was not the desired value. See the code
87 // in should_expand() to see how the initialization is handled
88 // now.
89 size_t MetaspaceGC::_capacity_until_GC = 0;
90 bool MetaspaceGC::_expand_after_GC = false;
91 uint MetaspaceGC::_shrink_factor = 0;
92 bool MetaspaceGC::_should_concurrent_collect = false;
94 // Blocks of space for metadata are allocated out of Metachunks.
95 //
96 // Metachunk are allocated out of MetadataVirtualspaces and once
97 // allocated there is no explicit link between a Metachunk and
98 // the MetadataVirtualspaces from which it was allocated.
99 //
100 // Each SpaceManager maintains a
101 // list of the chunks it is using and the current chunk. The current
102 // chunk is the chunk from which allocations are done. Space freed in
103 // a chunk is placed on the free list of blocks (BlockFreelist) and
104 // reused from there.
106 // Pointer to list of Metachunks.
107 class ChunkList VALUE_OBJ_CLASS_SPEC {
108 // List of free chunks
109 Metachunk* _head;
111 public:
112 // Constructor
113 ChunkList() : _head(NULL) {}
115 // Accessors
116 Metachunk* head() { return _head; }
117 void set_head(Metachunk* v) { _head = v; }
119 // Link at head of the list
120 void add_at_head(Metachunk* head, Metachunk* tail);
121 void add_at_head(Metachunk* head);
123 size_t sum_list_size();
124 size_t sum_list_count();
125 size_t sum_list_capacity();
126 };
128 // Manages the global free lists of chunks.
129 // Has three lists of free chunks, and a total size and
130 // count that includes all three
132 class ChunkManager VALUE_OBJ_CLASS_SPEC {
134 // Free list of chunks of different sizes.
135 // SmallChunk
136 // MediumChunk
137 // HumongousChunk
138 ChunkList _free_chunks[NumberOfFreeLists];
141 // HumongousChunk
142 ChunkTreeDictionary _humongous_dictionary;
144 // ChunkManager in all lists of this type
145 size_t _free_chunks_total;
146 size_t _free_chunks_count;
148 void dec_free_chunks_total(size_t v) {
149 assert(_free_chunks_count > 0 &&
150 _free_chunks_total > 0,
151 "About to go negative");
152 Atomic::add_ptr(-1, &_free_chunks_count);
153 jlong minus_v = (jlong) - (jlong) v;
154 Atomic::add_ptr(minus_v, &_free_chunks_total);
155 }
157 // Debug support
159 size_t sum_free_chunks();
160 size_t sum_free_chunks_count();
162 void locked_verify_free_chunks_total();
163 void slow_locked_verify_free_chunks_total() {
164 if (metaspace_slow_verify) {
165 locked_verify_free_chunks_total();
166 }
167 }
168 void locked_verify_free_chunks_count();
169 void slow_locked_verify_free_chunks_count() {
170 if (metaspace_slow_verify) {
171 locked_verify_free_chunks_count();
172 }
173 }
174 void verify_free_chunks_count();
176 public:
178 ChunkManager() : _free_chunks_total(0), _free_chunks_count(0) {}
180 // add or delete (return) a chunk to the global freelist.
181 Metachunk* chunk_freelist_allocate(size_t word_size);
182 void chunk_freelist_deallocate(Metachunk* chunk);
184 // Map a size to a list index assuming that there are lists
185 // for special, small, medium, and humongous chunks.
186 static ChunkIndex list_index(size_t size);
188 // Total of the space in the free chunks list
189 size_t free_chunks_total();
190 size_t free_chunks_total_in_bytes();
192 // Number of chunks in the free chunks list
193 size_t free_chunks_count();
195 void inc_free_chunks_total(size_t v, size_t count = 1) {
196 Atomic::add_ptr(count, &_free_chunks_count);
197 Atomic::add_ptr(v, &_free_chunks_total);
198 }
199 ChunkTreeDictionary* humongous_dictionary() {
200 return &_humongous_dictionary;
201 }
203 ChunkList* free_chunks(ChunkIndex index);
205 // Returns the list for the given chunk word size.
206 ChunkList* find_free_chunks_list(size_t word_size);
208 // Add and remove from a list by size. Selects
209 // list based on size of chunk.
210 void free_chunks_put(Metachunk* chuck);
211 Metachunk* free_chunks_get(size_t chunk_word_size);
213 // Debug support
214 void verify();
215 void slow_verify() {
216 if (metaspace_slow_verify) {
217 verify();
218 }
219 }
220 void locked_verify();
221 void slow_locked_verify() {
222 if (metaspace_slow_verify) {
223 locked_verify();
224 }
225 }
226 void verify_free_chunks_total();
228 void locked_print_free_chunks(outputStream* st);
229 void locked_print_sum_free_chunks(outputStream* st);
231 void print_on(outputStream* st);
232 };
235 // Used to manage the free list of Metablocks (a block corresponds
236 // to the allocation of a quantum of metadata).
237 class BlockFreelist VALUE_OBJ_CLASS_SPEC {
238 BlockTreeDictionary* _dictionary;
239 static Metablock* initialize_free_chunk(MetaWord* p, size_t word_size);
241 // Accessors
242 BlockTreeDictionary* dictionary() const { return _dictionary; }
244 public:
245 BlockFreelist();
246 ~BlockFreelist();
248 // Get and return a block to the free list
249 MetaWord* get_block(size_t word_size);
250 void return_block(MetaWord* p, size_t word_size);
252 size_t total_size() {
253 if (dictionary() == NULL) {
254 return 0;
255 } else {
256 return dictionary()->total_size();
257 }
258 }
260 void print_on(outputStream* st) const;
261 };
263 class VirtualSpaceNode : public CHeapObj<mtClass> {
264 friend class VirtualSpaceList;
266 // Link to next VirtualSpaceNode
267 VirtualSpaceNode* _next;
269 // total in the VirtualSpace
270 MemRegion _reserved;
271 ReservedSpace _rs;
272 VirtualSpace _virtual_space;
273 MetaWord* _top;
275 // Convenience functions for logical bottom and end
276 MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); }
277 MetaWord* end() const { return (MetaWord*) _virtual_space.high(); }
279 // Convenience functions to access the _virtual_space
280 char* low() const { return virtual_space()->low(); }
281 char* high() const { return virtual_space()->high(); }
283 public:
285 VirtualSpaceNode(size_t byte_size);
286 VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs) {}
287 ~VirtualSpaceNode();
289 // address of next available space in _virtual_space;
290 // Accessors
291 VirtualSpaceNode* next() { return _next; }
292 void set_next(VirtualSpaceNode* v) { _next = v; }
294 void set_reserved(MemRegion const v) { _reserved = v; }
295 void set_top(MetaWord* v) { _top = v; }
297 // Accessors
298 MemRegion* reserved() { return &_reserved; }
299 VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; }
301 // Returns true if "word_size" is available in the virtual space
302 bool is_available(size_t word_size) { return _top + word_size <= end(); }
304 MetaWord* top() const { return _top; }
305 void inc_top(size_t word_size) { _top += word_size; }
307 // used and capacity in this single entry in the list
308 size_t used_words_in_vs() const;
309 size_t capacity_words_in_vs() const;
311 bool initialize();
313 // get space from the virtual space
314 Metachunk* take_from_committed(size_t chunk_word_size);
316 // Allocate a chunk from the virtual space and return it.
317 Metachunk* get_chunk_vs(size_t chunk_word_size);
318 Metachunk* get_chunk_vs_with_expand(size_t chunk_word_size);
320 // Expands/shrinks the committed space in a virtual space. Delegates
321 // to Virtualspace
322 bool expand_by(size_t words, bool pre_touch = false);
323 bool shrink_by(size_t words);
325 #ifdef ASSERT
326 // Debug support
327 static void verify_virtual_space_total();
328 static void verify_virtual_space_count();
329 void mangle();
330 #endif
332 void print_on(outputStream* st) const;
333 };
335 // byte_size is the size of the associated virtualspace.
336 VirtualSpaceNode::VirtualSpaceNode(size_t byte_size) : _top(NULL), _next(NULL), _rs(0) {
337 // This allocates memory with mmap. For DumpSharedspaces, allocate the
338 // space at low memory so that other shared images don't conflict.
339 // This is the same address as memory needed for UseCompressedOops but
340 // compressed oops don't work with CDS (offsets in metadata are wrong), so
341 // borrow the same address.
342 if (DumpSharedSpaces) {
343 char* shared_base = (char*)HeapBaseMinAddress;
344 _rs = ReservedSpace(byte_size, 0, false, shared_base, 0);
345 if (_rs.is_reserved()) {
346 assert(_rs.base() == shared_base, "should match");
347 } else {
348 // If we are dumping the heap, then allocate a wasted block of address
349 // space in order to push the heap to a lower address. This extra
350 // address range allows for other (or larger) libraries to be loaded
351 // without them occupying the space required for the shared spaces.
352 uintx reserved = 0;
353 uintx block_size = 64*1024*1024;
354 while (reserved < SharedDummyBlockSize) {
355 char* dummy = os::reserve_memory(block_size);
356 reserved += block_size;
357 }
358 _rs = ReservedSpace(byte_size);
359 }
360 MetaspaceShared::set_shared_rs(&_rs);
361 } else {
362 _rs = ReservedSpace(byte_size);
363 }
365 MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass);
366 }
368 // List of VirtualSpaces for metadata allocation.
369 // It has a _next link for singly linked list and a MemRegion
370 // for total space in the VirtualSpace.
371 class VirtualSpaceList : public CHeapObj<mtClass> {
372 friend class VirtualSpaceNode;
374 enum VirtualSpaceSizes {
375 VirtualSpaceSize = 256 * K
376 };
378 // Global list of virtual spaces
379 // Head of the list
380 VirtualSpaceNode* _virtual_space_list;
381 // virtual space currently being used for allocations
382 VirtualSpaceNode* _current_virtual_space;
383 // Free chunk list for all other metadata
384 ChunkManager _chunk_manager;
386 // Can this virtual list allocate >1 spaces? Also, used to determine
387 // whether to allocate unlimited small chunks in this virtual space
388 bool _is_class;
389 bool can_grow() const { return !is_class() || !UseCompressedKlassPointers; }
391 // Sum of space in all virtual spaces and number of virtual spaces
392 size_t _virtual_space_total;
393 size_t _virtual_space_count;
395 ~VirtualSpaceList();
397 VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; }
399 void set_virtual_space_list(VirtualSpaceNode* v) {
400 _virtual_space_list = v;
401 }
402 void set_current_virtual_space(VirtualSpaceNode* v) {
403 _current_virtual_space = v;
404 }
406 void link_vs(VirtualSpaceNode* new_entry, size_t vs_word_size);
408 // Get another virtual space and add it to the list. This
409 // is typically prompted by a failed attempt to allocate a chunk
410 // and is typically followed by the allocation of a chunk.
411 bool grow_vs(size_t vs_word_size);
413 public:
414 VirtualSpaceList(size_t word_size);
415 VirtualSpaceList(ReservedSpace rs);
417 Metachunk* get_new_chunk(size_t word_size,
418 size_t grow_chunks_by_words,
419 size_t medium_chunk_bunch);
421 // Get the first chunk for a Metaspace. Used for
422 // special cases such as the boot class loader, reflection
423 // class loader and anonymous class loader.
424 Metachunk* get_initialization_chunk(size_t word_size, size_t chunk_bunch);
426 VirtualSpaceNode* current_virtual_space() {
427 return _current_virtual_space;
428 }
430 ChunkManager* chunk_manager() { return &_chunk_manager; }
431 bool is_class() const { return _is_class; }
433 // Allocate the first virtualspace.
434 void initialize(size_t word_size);
436 size_t virtual_space_total() { return _virtual_space_total; }
437 void inc_virtual_space_total(size_t v) {
438 Atomic::add_ptr(v, &_virtual_space_total);
439 }
441 size_t virtual_space_count() { return _virtual_space_count; }
442 void inc_virtual_space_count() {
443 Atomic::inc_ptr(&_virtual_space_count);
444 }
446 // Used and capacity in the entire list of virtual spaces.
447 // These are global values shared by all Metaspaces
448 size_t capacity_words_sum();
449 size_t capacity_bytes_sum() { return capacity_words_sum() * BytesPerWord; }
450 size_t used_words_sum();
451 size_t used_bytes_sum() { return used_words_sum() * BytesPerWord; }
453 bool contains(const void *ptr);
455 void print_on(outputStream* st) const;
457 class VirtualSpaceListIterator : public StackObj {
458 VirtualSpaceNode* _virtual_spaces;
459 public:
460 VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) :
461 _virtual_spaces(virtual_spaces) {}
463 bool repeat() {
464 return _virtual_spaces != NULL;
465 }
467 VirtualSpaceNode* get_next() {
468 VirtualSpaceNode* result = _virtual_spaces;
469 if (_virtual_spaces != NULL) {
470 _virtual_spaces = _virtual_spaces->next();
471 }
472 return result;
473 }
474 };
475 };
477 class Metadebug : AllStatic {
478 // Debugging support for Metaspaces
479 static int _deallocate_block_a_lot_count;
480 static int _deallocate_chunk_a_lot_count;
481 static int _allocation_fail_alot_count;
483 public:
484 static int deallocate_block_a_lot_count() {
485 return _deallocate_block_a_lot_count;
486 }
487 static void set_deallocate_block_a_lot_count(int v) {
488 _deallocate_block_a_lot_count = v;
489 }
490 static void inc_deallocate_block_a_lot_count() {
491 _deallocate_block_a_lot_count++;
492 }
493 static int deallocate_chunk_a_lot_count() {
494 return _deallocate_chunk_a_lot_count;
495 }
496 static void reset_deallocate_chunk_a_lot_count() {
497 _deallocate_chunk_a_lot_count = 1;
498 }
499 static void inc_deallocate_chunk_a_lot_count() {
500 _deallocate_chunk_a_lot_count++;
501 }
503 static void init_allocation_fail_alot_count();
504 #ifdef ASSERT
505 static bool test_metadata_failure();
506 #endif
508 static void deallocate_chunk_a_lot(SpaceManager* sm,
509 size_t chunk_word_size);
510 static void deallocate_block_a_lot(SpaceManager* sm,
511 size_t chunk_word_size);
513 };
515 int Metadebug::_deallocate_block_a_lot_count = 0;
516 int Metadebug::_deallocate_chunk_a_lot_count = 0;
517 int Metadebug::_allocation_fail_alot_count = 0;
519 // SpaceManager - used by Metaspace to handle allocations
520 class SpaceManager : public CHeapObj<mtClass> {
521 friend class Metaspace;
522 friend class Metadebug;
524 private:
526 // protects allocations and contains.
527 Mutex* const _lock;
529 // Chunk related size
530 size_t _medium_chunk_bunch;
532 // List of chunks in use by this SpaceManager. Allocations
533 // are done from the current chunk. The list is used for deallocating
534 // chunks when the SpaceManager is freed.
535 Metachunk* _chunks_in_use[NumberOfInUseLists];
536 Metachunk* _current_chunk;
538 // Virtual space where allocation comes from.
539 VirtualSpaceList* _vs_list;
541 // Number of small chunks to allocate to a manager
542 // If class space manager, small chunks are unlimited
543 static uint const _small_chunk_limit;
544 bool has_small_chunk_limit() { return !vs_list()->is_class(); }
546 // Sum of all space in allocated chunks
547 size_t _allocation_total;
549 // Free lists of blocks are per SpaceManager since they
550 // are assumed to be in chunks in use by the SpaceManager
551 // and all chunks in use by a SpaceManager are freed when
552 // the class loader using the SpaceManager is collected.
553 BlockFreelist _block_freelists;
555 // protects virtualspace and chunk expansions
556 static const char* _expand_lock_name;
557 static const int _expand_lock_rank;
558 static Mutex* const _expand_lock;
560 private:
561 // Accessors
562 Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; }
563 void set_chunks_in_use(ChunkIndex index, Metachunk* v) { _chunks_in_use[index] = v; }
565 BlockFreelist* block_freelists() const {
566 return (BlockFreelist*) &_block_freelists;
567 }
569 VirtualSpaceList* vs_list() const { return _vs_list; }
571 Metachunk* current_chunk() const { return _current_chunk; }
572 void set_current_chunk(Metachunk* v) {
573 _current_chunk = v;
574 }
576 Metachunk* find_current_chunk(size_t word_size);
578 // Add chunk to the list of chunks in use
579 void add_chunk(Metachunk* v, bool make_current);
581 Mutex* lock() const { return _lock; }
583 const char* chunk_size_name(ChunkIndex index) const;
585 protected:
586 void initialize();
588 public:
589 SpaceManager(Mutex* lock,
590 VirtualSpaceList* vs_list);
591 ~SpaceManager();
593 enum ChunkMultiples {
594 MediumChunkMultiple = 4
595 };
597 // Accessors
598 size_t specialized_chunk_size() { return SpecializedChunk; }
599 size_t small_chunk_size() { return (size_t) vs_list()->is_class() ? ClassSmallChunk : SmallChunk; }
600 size_t medium_chunk_size() { return (size_t) vs_list()->is_class() ? ClassMediumChunk : MediumChunk; }
601 size_t medium_chunk_bunch() { return medium_chunk_size() * MediumChunkMultiple; }
603 size_t allocation_total() const { return _allocation_total; }
604 void inc_allocation_total(size_t v) { Atomic::add_ptr(v, &_allocation_total); }
605 bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); }
607 static Mutex* expand_lock() { return _expand_lock; }
609 // Set the sizes for the initial chunks.
610 void get_initial_chunk_sizes(Metaspace::MetaspaceType type,
611 size_t* chunk_word_size,
612 size_t* class_chunk_word_size);
614 size_t sum_capacity_in_chunks_in_use() const;
615 size_t sum_used_in_chunks_in_use() const;
616 size_t sum_free_in_chunks_in_use() const;
617 size_t sum_waste_in_chunks_in_use() const;
618 size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const;
620 size_t sum_count_in_chunks_in_use();
621 size_t sum_count_in_chunks_in_use(ChunkIndex i);
623 Metachunk* get_new_chunk(size_t word_size, size_t grow_chunks_by_words);
625 // Block allocation and deallocation.
626 // Allocates a block from the current chunk
627 MetaWord* allocate(size_t word_size);
629 // Helper for allocations
630 MetaWord* allocate_work(size_t word_size);
632 // Returns a block to the per manager freelist
633 void deallocate(MetaWord* p, size_t word_size);
635 // Based on the allocation size and a minimum chunk size,
636 // returned chunk size (for expanding space for chunk allocation).
637 size_t calc_chunk_size(size_t allocation_word_size);
639 // Called when an allocation from the current chunk fails.
640 // Gets a new chunk (may require getting a new virtual space),
641 // and allocates from that chunk.
642 MetaWord* grow_and_allocate(size_t word_size);
644 // debugging support.
646 void dump(outputStream* const out) const;
647 void print_on(outputStream* st) const;
648 void locked_print_chunks_in_use_on(outputStream* st) const;
650 void verify();
651 void verify_chunk_size(Metachunk* chunk);
652 NOT_PRODUCT(void mangle_freed_chunks();)
653 #ifdef ASSERT
654 void verify_allocation_total();
655 #endif
656 };
658 uint const SpaceManager::_small_chunk_limit = 4;
660 const char* SpaceManager::_expand_lock_name =
661 "SpaceManager chunk allocation lock";
662 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1;
663 Mutex* const SpaceManager::_expand_lock =
664 new Mutex(SpaceManager::_expand_lock_rank,
665 SpaceManager::_expand_lock_name,
666 Mutex::_allow_vm_block_flag);
668 // BlockFreelist methods
670 BlockFreelist::BlockFreelist() : _dictionary(NULL) {}
672 BlockFreelist::~BlockFreelist() {
673 if (_dictionary != NULL) {
674 if (Verbose && TraceMetadataChunkAllocation) {
675 _dictionary->print_free_lists(gclog_or_tty);
676 }
677 delete _dictionary;
678 }
679 }
681 Metablock* BlockFreelist::initialize_free_chunk(MetaWord* p, size_t word_size) {
682 Metablock* block = (Metablock*) p;
683 block->set_word_size(word_size);
684 block->set_prev(NULL);
685 block->set_next(NULL);
687 return block;
688 }
690 void BlockFreelist::return_block(MetaWord* p, size_t word_size) {
691 Metablock* free_chunk = initialize_free_chunk(p, word_size);
692 if (dictionary() == NULL) {
693 _dictionary = new BlockTreeDictionary();
694 }
695 dictionary()->return_chunk(free_chunk);
696 }
698 MetaWord* BlockFreelist::get_block(size_t word_size) {
699 if (dictionary() == NULL) {
700 return NULL;
701 }
703 if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
704 // Dark matter. Too small for dictionary.
705 return NULL;
706 }
708 Metablock* free_block =
709 dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::exactly);
710 if (free_block == NULL) {
711 return NULL;
712 }
714 return (MetaWord*) free_block;
715 }
717 void BlockFreelist::print_on(outputStream* st) const {
718 if (dictionary() == NULL) {
719 return;
720 }
721 dictionary()->print_free_lists(st);
722 }
724 // VirtualSpaceNode methods
726 VirtualSpaceNode::~VirtualSpaceNode() {
727 _rs.release();
728 }
730 size_t VirtualSpaceNode::used_words_in_vs() const {
731 return pointer_delta(top(), bottom(), sizeof(MetaWord));
732 }
734 // Space committed in the VirtualSpace
735 size_t VirtualSpaceNode::capacity_words_in_vs() const {
736 return pointer_delta(end(), bottom(), sizeof(MetaWord));
737 }
740 // Allocates the chunk from the virtual space only.
741 // This interface is also used internally for debugging. Not all
742 // chunks removed here are necessarily used for allocation.
743 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) {
744 // Bottom of the new chunk
745 MetaWord* chunk_limit = top();
746 assert(chunk_limit != NULL, "Not safe to call this method");
748 if (!is_available(chunk_word_size)) {
749 if (TraceMetadataChunkAllocation) {
750 tty->print("VirtualSpaceNode::take_from_committed() not available %d words ", chunk_word_size);
751 // Dump some information about the virtual space that is nearly full
752 print_on(tty);
753 }
754 return NULL;
755 }
757 // Take the space (bump top on the current virtual space).
758 inc_top(chunk_word_size);
760 // Point the chunk at the space
761 Metachunk* result = Metachunk::initialize(chunk_limit, chunk_word_size);
762 return result;
763 }
766 // Expand the virtual space (commit more of the reserved space)
767 bool VirtualSpaceNode::expand_by(size_t words, bool pre_touch) {
768 size_t bytes = words * BytesPerWord;
769 bool result = virtual_space()->expand_by(bytes, pre_touch);
770 if (TraceMetavirtualspaceAllocation && !result) {
771 gclog_or_tty->print_cr("VirtualSpaceNode::expand_by() failed "
772 "for byte size " SIZE_FORMAT, bytes);
773 virtual_space()->print();
774 }
775 return result;
776 }
778 // Shrink the virtual space (commit more of the reserved space)
779 bool VirtualSpaceNode::shrink_by(size_t words) {
780 size_t bytes = words * BytesPerWord;
781 virtual_space()->shrink_by(bytes);
782 return true;
783 }
785 // Add another chunk to the chunk list.
787 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) {
788 assert_lock_strong(SpaceManager::expand_lock());
789 Metachunk* result = NULL;
791 return take_from_committed(chunk_word_size);
792 }
794 Metachunk* VirtualSpaceNode::get_chunk_vs_with_expand(size_t chunk_word_size) {
795 assert_lock_strong(SpaceManager::expand_lock());
797 Metachunk* new_chunk = get_chunk_vs(chunk_word_size);
799 if (new_chunk == NULL) {
800 // Only a small part of the virtualspace is committed when first
801 // allocated so committing more here can be expected.
802 size_t page_size_words = os::vm_page_size() / BytesPerWord;
803 size_t aligned_expand_vs_by_words = align_size_up(chunk_word_size,
804 page_size_words);
805 expand_by(aligned_expand_vs_by_words, false);
806 new_chunk = get_chunk_vs(chunk_word_size);
807 }
808 return new_chunk;
809 }
811 bool VirtualSpaceNode::initialize() {
813 if (!_rs.is_reserved()) {
814 return false;
815 }
817 // An allocation out of this Virtualspace that is larger
818 // than an initial commit size can waste that initial committed
819 // space.
820 size_t committed_byte_size = 0;
821 bool result = virtual_space()->initialize(_rs, committed_byte_size);
822 if (result) {
823 set_top((MetaWord*)virtual_space()->low());
824 set_reserved(MemRegion((HeapWord*)_rs.base(),
825 (HeapWord*)(_rs.base() + _rs.size())));
827 assert(reserved()->start() == (HeapWord*) _rs.base(),
828 err_msg("Reserved start was not set properly " PTR_FORMAT
829 " != " PTR_FORMAT, reserved()->start(), _rs.base()));
830 assert(reserved()->word_size() == _rs.size() / BytesPerWord,
831 err_msg("Reserved size was not set properly " SIZE_FORMAT
832 " != " SIZE_FORMAT, reserved()->word_size(),
833 _rs.size() / BytesPerWord));
834 }
836 return result;
837 }
839 void VirtualSpaceNode::print_on(outputStream* st) const {
840 size_t used = used_words_in_vs();
841 size_t capacity = capacity_words_in_vs();
842 VirtualSpace* vs = virtual_space();
843 st->print_cr(" space @ " PTR_FORMAT " " SIZE_FORMAT "K, %3d%% used "
844 "[" PTR_FORMAT ", " PTR_FORMAT ", "
845 PTR_FORMAT ", " PTR_FORMAT ")",
846 vs, capacity / K,
847 capacity == 0 ? 0 : used * 100 / capacity,
848 bottom(), top(), end(),
849 vs->high_boundary());
850 }
852 #ifdef ASSERT
853 void VirtualSpaceNode::mangle() {
854 size_t word_size = capacity_words_in_vs();
855 Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1);
856 }
857 #endif // ASSERT
859 // VirtualSpaceList methods
860 // Space allocated from the VirtualSpace
862 VirtualSpaceList::~VirtualSpaceList() {
863 VirtualSpaceListIterator iter(virtual_space_list());
864 while (iter.repeat()) {
865 VirtualSpaceNode* vsl = iter.get_next();
866 delete vsl;
867 }
868 }
870 size_t VirtualSpaceList::used_words_sum() {
871 size_t allocated_by_vs = 0;
872 VirtualSpaceListIterator iter(virtual_space_list());
873 while (iter.repeat()) {
874 VirtualSpaceNode* vsl = iter.get_next();
875 // Sum used region [bottom, top) in each virtualspace
876 allocated_by_vs += vsl->used_words_in_vs();
877 }
878 assert(allocated_by_vs >= chunk_manager()->free_chunks_total(),
879 err_msg("Total in free chunks " SIZE_FORMAT
880 " greater than total from virtual_spaces " SIZE_FORMAT,
881 allocated_by_vs, chunk_manager()->free_chunks_total()));
882 size_t used =
883 allocated_by_vs - chunk_manager()->free_chunks_total();
884 return used;
885 }
887 // Space available in all MetadataVirtualspaces allocated
888 // for metadata. This is the upper limit on the capacity
889 // of chunks allocated out of all the MetadataVirtualspaces.
890 size_t VirtualSpaceList::capacity_words_sum() {
891 size_t capacity = 0;
892 VirtualSpaceListIterator iter(virtual_space_list());
893 while (iter.repeat()) {
894 VirtualSpaceNode* vsl = iter.get_next();
895 capacity += vsl->capacity_words_in_vs();
896 }
897 return capacity;
898 }
900 VirtualSpaceList::VirtualSpaceList(size_t word_size ) :
901 _is_class(false),
902 _virtual_space_list(NULL),
903 _current_virtual_space(NULL),
904 _virtual_space_total(0),
905 _virtual_space_count(0) {
906 MutexLockerEx cl(SpaceManager::expand_lock(),
907 Mutex::_no_safepoint_check_flag);
908 bool initialization_succeeded = grow_vs(word_size);
910 assert(initialization_succeeded,
911 " VirtualSpaceList initialization should not fail");
912 }
914 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) :
915 _is_class(true),
916 _virtual_space_list(NULL),
917 _current_virtual_space(NULL),
918 _virtual_space_total(0),
919 _virtual_space_count(0) {
920 MutexLockerEx cl(SpaceManager::expand_lock(),
921 Mutex::_no_safepoint_check_flag);
922 VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs);
923 bool succeeded = class_entry->initialize();
924 assert(succeeded, " VirtualSpaceList initialization should not fail");
925 link_vs(class_entry, rs.size()/BytesPerWord);
926 }
928 // Allocate another meta virtual space and add it to the list.
929 bool VirtualSpaceList::grow_vs(size_t vs_word_size) {
930 assert_lock_strong(SpaceManager::expand_lock());
931 if (vs_word_size == 0) {
932 return false;
933 }
934 // Reserve the space
935 size_t vs_byte_size = vs_word_size * BytesPerWord;
936 assert(vs_byte_size % os::vm_page_size() == 0, "Not aligned");
938 // Allocate the meta virtual space and initialize it.
939 VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size);
940 if (!new_entry->initialize()) {
941 delete new_entry;
942 return false;
943 } else {
944 // ensure lock-free iteration sees fully initialized node
945 OrderAccess::storestore();
946 link_vs(new_entry, vs_word_size);
947 return true;
948 }
949 }
951 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry, size_t vs_word_size) {
952 if (virtual_space_list() == NULL) {
953 set_virtual_space_list(new_entry);
954 } else {
955 current_virtual_space()->set_next(new_entry);
956 }
957 set_current_virtual_space(new_entry);
958 inc_virtual_space_total(vs_word_size);
959 inc_virtual_space_count();
960 #ifdef ASSERT
961 new_entry->mangle();
962 #endif
963 if (TraceMetavirtualspaceAllocation && Verbose) {
964 VirtualSpaceNode* vsl = current_virtual_space();
965 vsl->print_on(tty);
966 }
967 }
969 Metachunk* VirtualSpaceList::get_new_chunk(size_t word_size,
970 size_t grow_chunks_by_words,
971 size_t medium_chunk_bunch) {
973 // Get a chunk from the chunk freelist
974 Metachunk* next = chunk_manager()->chunk_freelist_allocate(grow_chunks_by_words);
976 // Allocate a chunk out of the current virtual space.
977 if (next == NULL) {
978 next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
979 }
981 if (next == NULL) {
982 // Not enough room in current virtual space. Try to commit
983 // more space.
984 size_t expand_vs_by_words = MAX2(medium_chunk_bunch,
985 grow_chunks_by_words);
986 size_t page_size_words = os::vm_page_size() / BytesPerWord;
987 size_t aligned_expand_vs_by_words = align_size_up(expand_vs_by_words,
988 page_size_words);
989 bool vs_expanded =
990 current_virtual_space()->expand_by(aligned_expand_vs_by_words, false);
991 if (!vs_expanded) {
992 // Should the capacity of the metaspaces be expanded for
993 // this allocation? If it's the virtual space for classes and is
994 // being used for CompressedHeaders, don't allocate a new virtualspace.
995 if (can_grow() && MetaspaceGC::should_expand(this, word_size)) {
996 // Get another virtual space.
997 size_t grow_vs_words =
998 MAX2((size_t)VirtualSpaceSize, aligned_expand_vs_by_words);
999 if (grow_vs(grow_vs_words)) {
1000 // Got it. It's on the list now. Get a chunk from it.
1001 next = current_virtual_space()->get_chunk_vs_with_expand(grow_chunks_by_words);
1002 }
1003 } else {
1004 // Allocation will fail and induce a GC
1005 if (TraceMetadataChunkAllocation && Verbose) {
1006 gclog_or_tty->print_cr("VirtualSpaceList::get_new_chunk():"
1007 " Fail instead of expand the metaspace");
1008 }
1009 }
1010 } else {
1011 // The virtual space expanded, get a new chunk
1012 next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
1013 assert(next != NULL, "Just expanded, should succeed");
1014 }
1015 }
1017 assert(next == NULL || (next->next() == NULL && next->prev() == NULL),
1018 "New chunk is still on some list");
1019 return next;
1020 }
1022 Metachunk* VirtualSpaceList::get_initialization_chunk(size_t chunk_word_size,
1023 size_t chunk_bunch) {
1024 // Get a chunk from the chunk freelist
1025 Metachunk* new_chunk = get_new_chunk(chunk_word_size,
1026 chunk_word_size,
1027 chunk_bunch);
1028 return new_chunk;
1029 }
1031 void VirtualSpaceList::print_on(outputStream* st) const {
1032 if (TraceMetadataChunkAllocation && Verbose) {
1033 VirtualSpaceListIterator iter(virtual_space_list());
1034 while (iter.repeat()) {
1035 VirtualSpaceNode* node = iter.get_next();
1036 node->print_on(st);
1037 }
1038 }
1039 }
1041 bool VirtualSpaceList::contains(const void *ptr) {
1042 VirtualSpaceNode* list = virtual_space_list();
1043 VirtualSpaceListIterator iter(list);
1044 while (iter.repeat()) {
1045 VirtualSpaceNode* node = iter.get_next();
1046 if (node->reserved()->contains(ptr)) {
1047 return true;
1048 }
1049 }
1050 return false;
1051 }
1054 // MetaspaceGC methods
1056 // VM_CollectForMetadataAllocation is the vm operation used to GC.
1057 // Within the VM operation after the GC the attempt to allocate the metadata
1058 // should succeed. If the GC did not free enough space for the metaspace
1059 // allocation, the HWM is increased so that another virtualspace will be
1060 // allocated for the metadata. With perm gen the increase in the perm
1061 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The
1062 // metaspace policy uses those as the small and large steps for the HWM.
1063 //
1064 // After the GC the compute_new_size() for MetaspaceGC is called to
1065 // resize the capacity of the metaspaces. The current implementation
1066 // is based on the flags MinMetaspaceFreeRatio and MaxHeapFreeRatio used
1067 // to resize the Java heap by some GC's. New flags can be implemented
1068 // if really needed. MinHeapFreeRatio is used to calculate how much
1069 // free space is desirable in the metaspace capacity to decide how much
1070 // to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much
1071 // free space is desirable in the metaspace capacity before decreasing
1072 // the HWM.
1074 // Calculate the amount to increase the high water mark (HWM).
1075 // Increase by a minimum amount (MinMetaspaceExpansion) so that
1076 // another expansion is not requested too soon. If that is not
1077 // enough to satisfy the allocation (i.e. big enough for a word_size
1078 // allocation), increase by MaxMetaspaceExpansion. If that is still
1079 // not enough, expand by the size of the allocation (word_size) plus
1080 // some.
1081 size_t MetaspaceGC::delta_capacity_until_GC(size_t word_size) {
1082 size_t before_inc = MetaspaceGC::capacity_until_GC();
1083 size_t min_delta_words = MinMetaspaceExpansion / BytesPerWord;
1084 size_t max_delta_words = MaxMetaspaceExpansion / BytesPerWord;
1085 size_t page_size_words = os::vm_page_size() / BytesPerWord;
1086 size_t size_delta_words = align_size_up(word_size, page_size_words);
1087 size_t delta_words = MAX2(size_delta_words, min_delta_words);
1088 if (delta_words > min_delta_words) {
1089 // Don't want to hit the high water mark on the next
1090 // allocation so make the delta greater than just enough
1091 // for this allocation.
1092 delta_words = MAX2(delta_words, max_delta_words);
1093 if (delta_words > max_delta_words) {
1094 // This allocation is large but the next ones are probably not
1095 // so increase by the minimum.
1096 delta_words = delta_words + min_delta_words;
1097 }
1098 }
1099 return delta_words;
1100 }
1102 bool MetaspaceGC::should_expand(VirtualSpaceList* vsl, size_t word_size) {
1104 // Class virtual space should always be expanded. Call GC for the other
1105 // metadata virtual space.
1106 if (vsl == Metaspace::class_space_list()) return true;
1108 // If the user wants a limit, impose one.
1109 size_t max_metaspace_size_words = MaxMetaspaceSize / BytesPerWord;
1110 size_t metaspace_size_words = MetaspaceSize / BytesPerWord;
1111 if (!FLAG_IS_DEFAULT(MaxMetaspaceSize) &&
1112 vsl->capacity_words_sum() >= max_metaspace_size_words) {
1113 return false;
1114 }
1116 // If this is part of an allocation after a GC, expand
1117 // unconditionally.
1118 if(MetaspaceGC::expand_after_GC()) {
1119 return true;
1120 }
1122 // If the capacity is below the minimum capacity, allow the
1123 // expansion. Also set the high-water-mark (capacity_until_GC)
1124 // to that minimum capacity so that a GC will not be induced
1125 // until that minimum capacity is exceeded.
1126 if (vsl->capacity_words_sum() < metaspace_size_words ||
1127 capacity_until_GC() == 0) {
1128 set_capacity_until_GC(metaspace_size_words);
1129 return true;
1130 } else {
1131 if (vsl->capacity_words_sum() < capacity_until_GC()) {
1132 return true;
1133 } else {
1134 if (TraceMetadataChunkAllocation && Verbose) {
1135 gclog_or_tty->print_cr(" allocation request size " SIZE_FORMAT
1136 " capacity_until_GC " SIZE_FORMAT
1137 " capacity_words_sum " SIZE_FORMAT
1138 " used_words_sum " SIZE_FORMAT
1139 " free chunks " SIZE_FORMAT
1140 " free chunks count %d",
1141 word_size,
1142 capacity_until_GC(),
1143 vsl->capacity_words_sum(),
1144 vsl->used_words_sum(),
1145 vsl->chunk_manager()->free_chunks_total(),
1146 vsl->chunk_manager()->free_chunks_count());
1147 }
1148 return false;
1149 }
1150 }
1151 }
1153 // Variables are in bytes
1155 void MetaspaceGC::compute_new_size() {
1156 assert(_shrink_factor <= 100, "invalid shrink factor");
1157 uint current_shrink_factor = _shrink_factor;
1158 _shrink_factor = 0;
1160 VirtualSpaceList *vsl = Metaspace::space_list();
1162 size_t capacity_after_gc = vsl->capacity_bytes_sum();
1163 // Check to see if these two can be calculated without walking the CLDG
1164 size_t used_after_gc = vsl->used_bytes_sum();
1165 size_t capacity_until_GC = vsl->capacity_bytes_sum();
1166 size_t free_after_gc = capacity_until_GC - used_after_gc;
1168 const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0;
1169 const double maximum_used_percentage = 1.0 - minimum_free_percentage;
1171 const double min_tmp = used_after_gc / maximum_used_percentage;
1172 size_t minimum_desired_capacity =
1173 (size_t)MIN2(min_tmp, double(max_uintx));
1174 // Don't shrink less than the initial generation size
1175 minimum_desired_capacity = MAX2(minimum_desired_capacity,
1176 MetaspaceSize);
1178 if (PrintGCDetails && Verbose) {
1179 const double free_percentage = ((double)free_after_gc) / capacity_until_GC;
1180 gclog_or_tty->print_cr("\nMetaspaceGC::compute_new_size: ");
1181 gclog_or_tty->print_cr(" "
1182 " minimum_free_percentage: %6.2f"
1183 " maximum_used_percentage: %6.2f",
1184 minimum_free_percentage,
1185 maximum_used_percentage);
1186 double d_free_after_gc = free_after_gc / (double) K;
1187 gclog_or_tty->print_cr(" "
1188 " free_after_gc : %6.1fK"
1189 " used_after_gc : %6.1fK"
1190 " capacity_after_gc : %6.1fK"
1191 " metaspace HWM : %6.1fK",
1192 free_after_gc / (double) K,
1193 used_after_gc / (double) K,
1194 capacity_after_gc / (double) K,
1195 capacity_until_GC / (double) K);
1196 gclog_or_tty->print_cr(" "
1197 " free_percentage: %6.2f",
1198 free_percentage);
1199 }
1202 if (capacity_until_GC < minimum_desired_capacity) {
1203 // If we have less capacity below the metaspace HWM, then
1204 // increment the HWM.
1205 size_t expand_bytes = minimum_desired_capacity - capacity_until_GC;
1206 // Don't expand unless it's significant
1207 if (expand_bytes >= MinMetaspaceExpansion) {
1208 size_t expand_words = expand_bytes / BytesPerWord;
1209 MetaspaceGC::inc_capacity_until_GC(expand_words);
1210 }
1211 if (PrintGCDetails && Verbose) {
1212 size_t new_capacity_until_GC = MetaspaceGC::capacity_until_GC_in_bytes();
1213 gclog_or_tty->print_cr(" expanding:"
1214 " minimum_desired_capacity: %6.1fK"
1215 " expand_words: %6.1fK"
1216 " MinMetaspaceExpansion: %6.1fK"
1217 " new metaspace HWM: %6.1fK",
1218 minimum_desired_capacity / (double) K,
1219 expand_bytes / (double) K,
1220 MinMetaspaceExpansion / (double) K,
1221 new_capacity_until_GC / (double) K);
1222 }
1223 return;
1224 }
1226 // No expansion, now see if we want to shrink
1227 size_t shrink_words = 0;
1228 // We would never want to shrink more than this
1229 size_t max_shrink_words = capacity_until_GC - minimum_desired_capacity;
1230 assert(max_shrink_words >= 0, err_msg("max_shrink_words " SIZE_FORMAT,
1231 max_shrink_words));
1233 // Should shrinking be considered?
1234 if (MaxMetaspaceFreeRatio < 100) {
1235 const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0;
1236 const double minimum_used_percentage = 1.0 - maximum_free_percentage;
1237 const double max_tmp = used_after_gc / minimum_used_percentage;
1238 size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx));
1239 maximum_desired_capacity = MAX2(maximum_desired_capacity,
1240 MetaspaceSize);
1241 if (PrintGC && Verbose) {
1242 gclog_or_tty->print_cr(" "
1243 " maximum_free_percentage: %6.2f"
1244 " minimum_used_percentage: %6.2f",
1245 maximum_free_percentage,
1246 minimum_used_percentage);
1247 gclog_or_tty->print_cr(" "
1248 " capacity_until_GC: %6.1fK"
1249 " minimum_desired_capacity: %6.1fK"
1250 " maximum_desired_capacity: %6.1fK",
1251 capacity_until_GC / (double) K,
1252 minimum_desired_capacity / (double) K,
1253 maximum_desired_capacity / (double) K);
1254 }
1256 assert(minimum_desired_capacity <= maximum_desired_capacity,
1257 "sanity check");
1259 if (capacity_until_GC > maximum_desired_capacity) {
1260 // Capacity too large, compute shrinking size
1261 shrink_words = capacity_until_GC - maximum_desired_capacity;
1262 // We don't want shrink all the way back to initSize if people call
1263 // System.gc(), because some programs do that between "phases" and then
1264 // we'd just have to grow the heap up again for the next phase. So we
1265 // damp the shrinking: 0% on the first call, 10% on the second call, 40%
1266 // on the third call, and 100% by the fourth call. But if we recompute
1267 // size without shrinking, it goes back to 0%.
1268 shrink_words = shrink_words / 100 * current_shrink_factor;
1269 assert(shrink_words <= max_shrink_words,
1270 err_msg("invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT,
1271 shrink_words, max_shrink_words));
1272 if (current_shrink_factor == 0) {
1273 _shrink_factor = 10;
1274 } else {
1275 _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100);
1276 }
1277 if (PrintGCDetails && Verbose) {
1278 gclog_or_tty->print_cr(" "
1279 " shrinking:"
1280 " initSize: %.1fK"
1281 " maximum_desired_capacity: %.1fK",
1282 MetaspaceSize / (double) K,
1283 maximum_desired_capacity / (double) K);
1284 gclog_or_tty->print_cr(" "
1285 " shrink_words: %.1fK"
1286 " current_shrink_factor: %d"
1287 " new shrink factor: %d"
1288 " MinMetaspaceExpansion: %.1fK",
1289 shrink_words / (double) K,
1290 current_shrink_factor,
1291 _shrink_factor,
1292 MinMetaspaceExpansion / (double) K);
1293 }
1294 }
1295 }
1298 // Don't shrink unless it's significant
1299 if (shrink_words >= MinMetaspaceExpansion) {
1300 VirtualSpaceNode* csp = vsl->current_virtual_space();
1301 size_t available_to_shrink = csp->capacity_words_in_vs() -
1302 csp->used_words_in_vs();
1303 shrink_words = MIN2(shrink_words, available_to_shrink);
1304 csp->shrink_by(shrink_words);
1305 MetaspaceGC::dec_capacity_until_GC(shrink_words);
1306 if (PrintGCDetails && Verbose) {
1307 size_t new_capacity_until_GC = MetaspaceGC::capacity_until_GC_in_bytes();
1308 gclog_or_tty->print_cr(" metaspace HWM: %.1fK", new_capacity_until_GC / (double) K);
1309 }
1310 }
1311 assert(used_after_gc <= vsl->capacity_bytes_sum(),
1312 "sanity check");
1314 }
1316 // Metadebug methods
1318 void Metadebug::deallocate_chunk_a_lot(SpaceManager* sm,
1319 size_t chunk_word_size){
1320 #ifdef ASSERT
1321 VirtualSpaceList* vsl = sm->vs_list();
1322 if (MetaDataDeallocateALot &&
1323 Metadebug::deallocate_chunk_a_lot_count() % MetaDataDeallocateALotInterval == 0 ) {
1324 Metadebug::reset_deallocate_chunk_a_lot_count();
1325 for (uint i = 0; i < metadata_deallocate_a_lock_chunk; i++) {
1326 Metachunk* dummy_chunk = vsl->current_virtual_space()->take_from_committed(chunk_word_size);
1327 if (dummy_chunk == NULL) {
1328 break;
1329 }
1330 vsl->chunk_manager()->chunk_freelist_deallocate(dummy_chunk);
1332 if (TraceMetadataChunkAllocation && Verbose) {
1333 gclog_or_tty->print("Metadebug::deallocate_chunk_a_lot: %d) ",
1334 sm->sum_count_in_chunks_in_use());
1335 dummy_chunk->print_on(gclog_or_tty);
1336 gclog_or_tty->print_cr(" Free chunks total %d count %d",
1337 vsl->chunk_manager()->free_chunks_total(),
1338 vsl->chunk_manager()->free_chunks_count());
1339 }
1340 }
1341 } else {
1342 Metadebug::inc_deallocate_chunk_a_lot_count();
1343 }
1344 #endif
1345 }
1347 void Metadebug::deallocate_block_a_lot(SpaceManager* sm,
1348 size_t raw_word_size){
1349 #ifdef ASSERT
1350 if (MetaDataDeallocateALot &&
1351 Metadebug::deallocate_block_a_lot_count() % MetaDataDeallocateALotInterval == 0 ) {
1352 Metadebug::set_deallocate_block_a_lot_count(0);
1353 for (uint i = 0; i < metadata_deallocate_a_lot_block; i++) {
1354 MetaWord* dummy_block = sm->allocate_work(raw_word_size);
1355 if (dummy_block == 0) {
1356 break;
1357 }
1358 sm->deallocate(dummy_block, raw_word_size);
1359 }
1360 } else {
1361 Metadebug::inc_deallocate_block_a_lot_count();
1362 }
1363 #endif
1364 }
1366 void Metadebug::init_allocation_fail_alot_count() {
1367 if (MetadataAllocationFailALot) {
1368 _allocation_fail_alot_count =
1369 1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0));
1370 }
1371 }
1373 #ifdef ASSERT
1374 bool Metadebug::test_metadata_failure() {
1375 if (MetadataAllocationFailALot &&
1376 Threads::is_vm_complete()) {
1377 if (_allocation_fail_alot_count > 0) {
1378 _allocation_fail_alot_count--;
1379 } else {
1380 if (TraceMetadataChunkAllocation && Verbose) {
1381 gclog_or_tty->print_cr("Metadata allocation failing for "
1382 "MetadataAllocationFailALot");
1383 }
1384 init_allocation_fail_alot_count();
1385 return true;
1386 }
1387 }
1388 return false;
1389 }
1390 #endif
1392 // ChunkList methods
1394 size_t ChunkList::sum_list_size() {
1395 size_t result = 0;
1396 Metachunk* cur = head();
1397 while (cur != NULL) {
1398 result += cur->word_size();
1399 cur = cur->next();
1400 }
1401 return result;
1402 }
1404 size_t ChunkList::sum_list_count() {
1405 size_t result = 0;
1406 Metachunk* cur = head();
1407 while (cur != NULL) {
1408 result++;
1409 cur = cur->next();
1410 }
1411 return result;
1412 }
1414 size_t ChunkList::sum_list_capacity() {
1415 size_t result = 0;
1416 Metachunk* cur = head();
1417 while (cur != NULL) {
1418 result += cur->capacity_word_size();
1419 cur = cur->next();
1420 }
1421 return result;
1422 }
1424 void ChunkList::add_at_head(Metachunk* head, Metachunk* tail) {
1425 assert_lock_strong(SpaceManager::expand_lock());
1426 assert(head == tail || tail->next() == NULL,
1427 "Not the tail or the head has already been added to a list");
1429 if (TraceMetadataChunkAllocation && Verbose) {
1430 gclog_or_tty->print("ChunkList::add_at_head(head, tail): ");
1431 Metachunk* cur = head;
1432 while (cur != NULL) {
1433 gclog_or_tty->print(PTR_FORMAT " (" SIZE_FORMAT ") ", cur, cur->word_size());
1434 cur = cur->next();
1435 }
1436 gclog_or_tty->print_cr("");
1437 }
1439 if (tail != NULL) {
1440 tail->set_next(_head);
1441 }
1442 set_head(head);
1443 }
1445 void ChunkList::add_at_head(Metachunk* list) {
1446 if (list == NULL) {
1447 // Nothing to add
1448 return;
1449 }
1450 assert_lock_strong(SpaceManager::expand_lock());
1451 Metachunk* head = list;
1452 Metachunk* tail = list;
1453 Metachunk* cur = head->next();
1454 // Search for the tail since it is not passed.
1455 while (cur != NULL) {
1456 tail = cur;
1457 cur = cur->next();
1458 }
1459 add_at_head(head, tail);
1460 }
1462 // ChunkManager methods
1464 // Verification of _free_chunks_total and _free_chunks_count does not
1465 // work with the CMS collector because its use of additional locks
1466 // complicate the mutex deadlock detection but it can still be useful
1467 // for detecting errors in the chunk accounting with other collectors.
1469 size_t ChunkManager::free_chunks_total() {
1470 #ifdef ASSERT
1471 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
1472 MutexLockerEx cl(SpaceManager::expand_lock(),
1473 Mutex::_no_safepoint_check_flag);
1474 slow_locked_verify_free_chunks_total();
1475 }
1476 #endif
1477 return _free_chunks_total;
1478 }
1480 size_t ChunkManager::free_chunks_total_in_bytes() {
1481 return free_chunks_total() * BytesPerWord;
1482 }
1484 size_t ChunkManager::free_chunks_count() {
1485 #ifdef ASSERT
1486 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
1487 MutexLockerEx cl(SpaceManager::expand_lock(),
1488 Mutex::_no_safepoint_check_flag);
1489 // This lock is only needed in debug because the verification
1490 // of the _free_chunks_totals walks the list of free chunks
1491 slow_locked_verify_free_chunks_count();
1492 }
1493 #endif
1494 return _free_chunks_count;
1495 }
1497 void ChunkManager::locked_verify_free_chunks_total() {
1498 assert_lock_strong(SpaceManager::expand_lock());
1499 assert(sum_free_chunks() == _free_chunks_total,
1500 err_msg("_free_chunks_total " SIZE_FORMAT " is not the"
1501 " same as sum " SIZE_FORMAT, _free_chunks_total,
1502 sum_free_chunks()));
1503 }
1505 void ChunkManager::verify_free_chunks_total() {
1506 MutexLockerEx cl(SpaceManager::expand_lock(),
1507 Mutex::_no_safepoint_check_flag);
1508 locked_verify_free_chunks_total();
1509 }
1511 void ChunkManager::locked_verify_free_chunks_count() {
1512 assert_lock_strong(SpaceManager::expand_lock());
1513 assert(sum_free_chunks_count() == _free_chunks_count,
1514 err_msg("_free_chunks_count " SIZE_FORMAT " is not the"
1515 " same as sum " SIZE_FORMAT, _free_chunks_count,
1516 sum_free_chunks_count()));
1517 }
1519 void ChunkManager::verify_free_chunks_count() {
1520 #ifdef ASSERT
1521 MutexLockerEx cl(SpaceManager::expand_lock(),
1522 Mutex::_no_safepoint_check_flag);
1523 locked_verify_free_chunks_count();
1524 #endif
1525 }
1527 void ChunkManager::verify() {
1528 MutexLockerEx cl(SpaceManager::expand_lock(),
1529 Mutex::_no_safepoint_check_flag);
1530 locked_verify();
1531 }
1533 void ChunkManager::locked_verify() {
1534 locked_verify_free_chunks_count();
1535 locked_verify_free_chunks_total();
1536 }
1538 void ChunkManager::locked_print_free_chunks(outputStream* st) {
1539 assert_lock_strong(SpaceManager::expand_lock());
1540 st->print_cr("Free chunk total " SIZE_FORMAT " count " SIZE_FORMAT,
1541 _free_chunks_total, _free_chunks_count);
1542 }
1544 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) {
1545 assert_lock_strong(SpaceManager::expand_lock());
1546 st->print_cr("Sum free chunk total " SIZE_FORMAT " count " SIZE_FORMAT,
1547 sum_free_chunks(), sum_free_chunks_count());
1548 }
1549 ChunkList* ChunkManager::free_chunks(ChunkIndex index) {
1550 return &_free_chunks[index];
1551 }
1553 // These methods that sum the free chunk lists are used in printing
1554 // methods that are used in product builds.
1555 size_t ChunkManager::sum_free_chunks() {
1556 assert_lock_strong(SpaceManager::expand_lock());
1557 size_t result = 0;
1558 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1559 ChunkList* list = free_chunks(i);
1561 if (list == NULL) {
1562 continue;
1563 }
1565 result = result + list->sum_list_capacity();
1566 }
1567 result = result + humongous_dictionary()->total_size();
1568 return result;
1569 }
1571 size_t ChunkManager::sum_free_chunks_count() {
1572 assert_lock_strong(SpaceManager::expand_lock());
1573 size_t count = 0;
1574 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1575 ChunkList* list = free_chunks(i);
1576 if (list == NULL) {
1577 continue;
1578 }
1579 count = count + list->sum_list_count();
1580 }
1581 count = count + humongous_dictionary()->total_free_blocks();
1582 return count;
1583 }
1585 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) {
1586 ChunkIndex index = list_index(word_size);
1587 assert(index < HumongousIndex, "No humongous list");
1588 return free_chunks(index);
1589 }
1591 void ChunkManager::free_chunks_put(Metachunk* chunk) {
1592 assert_lock_strong(SpaceManager::expand_lock());
1593 ChunkList* free_list = find_free_chunks_list(chunk->word_size());
1594 chunk->set_next(free_list->head());
1595 free_list->set_head(chunk);
1596 // chunk is being returned to the chunk free list
1597 inc_free_chunks_total(chunk->capacity_word_size());
1598 slow_locked_verify();
1599 }
1601 void ChunkManager::chunk_freelist_deallocate(Metachunk* chunk) {
1602 // The deallocation of a chunk originates in the freelist
1603 // manangement code for a Metaspace and does not hold the
1604 // lock.
1605 assert(chunk != NULL, "Deallocating NULL");
1606 assert_lock_strong(SpaceManager::expand_lock());
1607 slow_locked_verify();
1608 if (TraceMetadataChunkAllocation) {
1609 tty->print_cr("ChunkManager::chunk_freelist_deallocate: chunk "
1610 PTR_FORMAT " size " SIZE_FORMAT,
1611 chunk, chunk->word_size());
1612 }
1613 free_chunks_put(chunk);
1614 }
1616 Metachunk* ChunkManager::free_chunks_get(size_t word_size) {
1617 assert_lock_strong(SpaceManager::expand_lock());
1619 slow_locked_verify();
1621 Metachunk* chunk = NULL;
1622 if (list_index(word_size) != HumongousIndex) {
1623 ChunkList* free_list = find_free_chunks_list(word_size);
1624 assert(free_list != NULL, "Sanity check");
1626 chunk = free_list->head();
1627 debug_only(Metachunk* debug_head = chunk;)
1629 if (chunk == NULL) {
1630 return NULL;
1631 }
1633 // Remove the chunk as the head of the list.
1634 free_list->set_head(chunk->next());
1636 // Chunk is being removed from the chunks free list.
1637 dec_free_chunks_total(chunk->capacity_word_size());
1639 if (TraceMetadataChunkAllocation && Verbose) {
1640 tty->print_cr("ChunkManager::free_chunks_get: free_list "
1641 PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT,
1642 free_list, chunk, chunk->word_size());
1643 }
1644 } else {
1645 chunk = humongous_dictionary()->get_chunk(
1646 word_size,
1647 FreeBlockDictionary<Metachunk>::atLeast);
1649 if (chunk != NULL) {
1650 if (TraceMetadataHumongousAllocation) {
1651 size_t waste = chunk->word_size() - word_size;
1652 tty->print_cr("Free list allocate humongous chunk size " SIZE_FORMAT
1653 " for requested size " SIZE_FORMAT
1654 " waste " SIZE_FORMAT,
1655 chunk->word_size(), word_size, waste);
1656 }
1657 // Chunk is being removed from the chunks free list.
1658 dec_free_chunks_total(chunk->capacity_word_size());
1659 #ifdef ASSERT
1660 chunk->set_is_free(false);
1661 #endif
1662 } else {
1663 return NULL;
1664 }
1665 }
1667 // Remove it from the links to this freelist
1668 chunk->set_next(NULL);
1669 chunk->set_prev(NULL);
1670 slow_locked_verify();
1671 return chunk;
1672 }
1674 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) {
1675 assert_lock_strong(SpaceManager::expand_lock());
1676 slow_locked_verify();
1678 // Take from the beginning of the list
1679 Metachunk* chunk = free_chunks_get(word_size);
1680 if (chunk == NULL) {
1681 return NULL;
1682 }
1684 assert((word_size <= chunk->word_size()) ||
1685 list_index(chunk->word_size() == HumongousIndex),
1686 "Non-humongous variable sized chunk");
1687 if (TraceMetadataChunkAllocation) {
1688 size_t list_count;
1689 if (list_index(word_size) < HumongousIndex) {
1690 ChunkList* list = find_free_chunks_list(word_size);
1691 list_count = list->sum_list_count();
1692 } else {
1693 list_count = humongous_dictionary()->total_count();
1694 }
1695 tty->print("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk "
1696 PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ",
1697 this, chunk, chunk->word_size(), list_count);
1698 locked_print_free_chunks(tty);
1699 }
1701 return chunk;
1702 }
1704 void ChunkManager::print_on(outputStream* out) {
1705 if (PrintFLSStatistics != 0) {
1706 humongous_dictionary()->report_statistics();
1707 }
1708 }
1710 // SpaceManager methods
1712 void SpaceManager::get_initial_chunk_sizes(Metaspace::MetaspaceType type,
1713 size_t* chunk_word_size,
1714 size_t* class_chunk_word_size) {
1715 switch (type) {
1716 case Metaspace::BootMetaspaceType:
1717 *chunk_word_size = Metaspace::first_chunk_word_size();
1718 *class_chunk_word_size = Metaspace::first_class_chunk_word_size();
1719 break;
1720 case Metaspace::ROMetaspaceType:
1721 *chunk_word_size = SharedReadOnlySize / wordSize;
1722 *class_chunk_word_size = ClassSpecializedChunk;
1723 break;
1724 case Metaspace::ReadWriteMetaspaceType:
1725 *chunk_word_size = SharedReadWriteSize / wordSize;
1726 *class_chunk_word_size = ClassSpecializedChunk;
1727 break;
1728 case Metaspace::AnonymousMetaspaceType:
1729 case Metaspace::ReflectionMetaspaceType:
1730 *chunk_word_size = SpecializedChunk;
1731 *class_chunk_word_size = ClassSpecializedChunk;
1732 break;
1733 default:
1734 *chunk_word_size = SmallChunk;
1735 *class_chunk_word_size = ClassSmallChunk;
1736 break;
1737 }
1738 assert(*chunk_word_size != 0 && *class_chunk_word_size != 0,
1739 err_msg("Initial chunks sizes bad: data " SIZE_FORMAT
1740 " class " SIZE_FORMAT,
1741 *chunk_word_size, *class_chunk_word_size));
1742 }
1744 size_t SpaceManager::sum_free_in_chunks_in_use() const {
1745 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1746 size_t free = 0;
1747 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1748 Metachunk* chunk = chunks_in_use(i);
1749 while (chunk != NULL) {
1750 free += chunk->free_word_size();
1751 chunk = chunk->next();
1752 }
1753 }
1754 return free;
1755 }
1757 size_t SpaceManager::sum_waste_in_chunks_in_use() const {
1758 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1759 size_t result = 0;
1760 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1761 result += sum_waste_in_chunks_in_use(i);
1762 }
1764 return result;
1765 }
1767 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const {
1768 size_t result = 0;
1769 Metachunk* chunk = chunks_in_use(index);
1770 // Count the free space in all the chunk but not the
1771 // current chunk from which allocations are still being done.
1772 if (chunk != NULL) {
1773 Metachunk* prev = chunk;
1774 while (chunk != NULL && chunk != current_chunk()) {
1775 result += chunk->free_word_size();
1776 prev = chunk;
1777 chunk = chunk->next();
1778 }
1779 }
1780 return result;
1781 }
1783 size_t SpaceManager::sum_capacity_in_chunks_in_use() const {
1784 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1785 size_t sum = 0;
1786 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1787 Metachunk* chunk = chunks_in_use(i);
1788 while (chunk != NULL) {
1789 // Just changed this sum += chunk->capacity_word_size();
1790 // sum += chunk->word_size() - Metachunk::overhead();
1791 sum += chunk->capacity_word_size();
1792 chunk = chunk->next();
1793 }
1794 }
1795 return sum;
1796 }
1798 size_t SpaceManager::sum_count_in_chunks_in_use() {
1799 size_t count = 0;
1800 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1801 count = count + sum_count_in_chunks_in_use(i);
1802 }
1804 return count;
1805 }
1807 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) {
1808 size_t count = 0;
1809 Metachunk* chunk = chunks_in_use(i);
1810 while (chunk != NULL) {
1811 count++;
1812 chunk = chunk->next();
1813 }
1814 return count;
1815 }
1818 size_t SpaceManager::sum_used_in_chunks_in_use() const {
1819 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1820 size_t used = 0;
1821 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1822 Metachunk* chunk = chunks_in_use(i);
1823 while (chunk != NULL) {
1824 used += chunk->used_word_size();
1825 chunk = chunk->next();
1826 }
1827 }
1828 return used;
1829 }
1831 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const {
1833 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1834 Metachunk* chunk = chunks_in_use(i);
1835 st->print("SpaceManager: %s " PTR_FORMAT,
1836 chunk_size_name(i), chunk);
1837 if (chunk != NULL) {
1838 st->print_cr(" free " SIZE_FORMAT,
1839 chunk->free_word_size());
1840 } else {
1841 st->print_cr("");
1842 }
1843 }
1845 vs_list()->chunk_manager()->locked_print_free_chunks(st);
1846 vs_list()->chunk_manager()->locked_print_sum_free_chunks(st);
1847 }
1849 size_t SpaceManager::calc_chunk_size(size_t word_size) {
1851 // Decide between a small chunk and a medium chunk. Up to
1852 // _small_chunk_limit small chunks can be allocated but
1853 // once a medium chunk has been allocated, no more small
1854 // chunks will be allocated.
1855 size_t chunk_word_size;
1856 if (chunks_in_use(MediumIndex) == NULL &&
1857 (!has_small_chunk_limit() ||
1858 sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit)) {
1859 chunk_word_size = (size_t) small_chunk_size();
1860 if (word_size + Metachunk::overhead() > small_chunk_size()) {
1861 chunk_word_size = medium_chunk_size();
1862 }
1863 } else {
1864 chunk_word_size = medium_chunk_size();
1865 }
1867 // Might still need a humongous chunk. Enforce an
1868 // eight word granularity to facilitate reuse (some
1869 // wastage but better chance of reuse).
1870 size_t if_humongous_sized_chunk =
1871 align_size_up(word_size + Metachunk::overhead(),
1872 HumongousChunkGranularity);
1873 chunk_word_size =
1874 MAX2((size_t) chunk_word_size, if_humongous_sized_chunk);
1876 assert(!SpaceManager::is_humongous(word_size) ||
1877 chunk_word_size == if_humongous_sized_chunk,
1878 err_msg("Size calculation is wrong, word_size " SIZE_FORMAT
1879 " chunk_word_size " SIZE_FORMAT,
1880 word_size, chunk_word_size));
1881 if (TraceMetadataHumongousAllocation &&
1882 SpaceManager::is_humongous(word_size)) {
1883 gclog_or_tty->print_cr("Metadata humongous allocation:");
1884 gclog_or_tty->print_cr(" word_size " PTR_FORMAT, word_size);
1885 gclog_or_tty->print_cr(" chunk_word_size " PTR_FORMAT,
1886 chunk_word_size);
1887 gclog_or_tty->print_cr(" chunk overhead " PTR_FORMAT,
1888 Metachunk::overhead());
1889 }
1890 return chunk_word_size;
1891 }
1893 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) {
1894 assert(vs_list()->current_virtual_space() != NULL,
1895 "Should have been set");
1896 assert(current_chunk() == NULL ||
1897 current_chunk()->allocate(word_size) == NULL,
1898 "Don't need to expand");
1899 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
1901 if (TraceMetadataChunkAllocation && Verbose) {
1902 size_t words_left = 0;
1903 size_t words_used = 0;
1904 if (current_chunk() != NULL) {
1905 words_left = current_chunk()->free_word_size();
1906 words_used = current_chunk()->used_word_size();
1907 }
1908 gclog_or_tty->print_cr("SpaceManager::grow_and_allocate for " SIZE_FORMAT
1909 " words " SIZE_FORMAT " words used " SIZE_FORMAT
1910 " words left",
1911 word_size, words_used, words_left);
1912 }
1914 // Get another chunk out of the virtual space
1915 size_t grow_chunks_by_words = calc_chunk_size(word_size);
1916 Metachunk* next = get_new_chunk(word_size, grow_chunks_by_words);
1918 // If a chunk was available, add it to the in-use chunk list
1919 // and do an allocation from it.
1920 if (next != NULL) {
1921 Metadebug::deallocate_chunk_a_lot(this, grow_chunks_by_words);
1922 // Add to this manager's list of chunks in use.
1923 add_chunk(next, false);
1924 return next->allocate(word_size);
1925 }
1926 return NULL;
1927 }
1929 void SpaceManager::print_on(outputStream* st) const {
1931 for (ChunkIndex i = ZeroIndex;
1932 i < NumberOfInUseLists ;
1933 i = next_chunk_index(i) ) {
1934 st->print_cr(" chunks_in_use " PTR_FORMAT " chunk size " PTR_FORMAT,
1935 chunks_in_use(i),
1936 chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size());
1937 }
1938 st->print_cr(" waste: Small " SIZE_FORMAT " Medium " SIZE_FORMAT
1939 " Humongous " SIZE_FORMAT,
1940 sum_waste_in_chunks_in_use(SmallIndex),
1941 sum_waste_in_chunks_in_use(MediumIndex),
1942 sum_waste_in_chunks_in_use(HumongousIndex));
1943 // block free lists
1944 if (block_freelists() != NULL) {
1945 st->print_cr("total in block free lists " SIZE_FORMAT,
1946 block_freelists()->total_size());
1947 }
1948 }
1950 SpaceManager::SpaceManager(Mutex* lock,
1951 VirtualSpaceList* vs_list) :
1952 _vs_list(vs_list),
1953 _allocation_total(0),
1954 _lock(lock)
1955 {
1956 initialize();
1957 }
1959 void SpaceManager::initialize() {
1960 Metadebug::init_allocation_fail_alot_count();
1961 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1962 _chunks_in_use[i] = NULL;
1963 }
1964 _current_chunk = NULL;
1965 if (TraceMetadataChunkAllocation && Verbose) {
1966 gclog_or_tty->print_cr("SpaceManager(): " PTR_FORMAT, this);
1967 }
1968 }
1970 SpaceManager::~SpaceManager() {
1971 // This call this->_lock which can't be done while holding expand_lock()
1972 const size_t in_use_before = sum_capacity_in_chunks_in_use();
1974 MutexLockerEx fcl(SpaceManager::expand_lock(),
1975 Mutex::_no_safepoint_check_flag);
1977 ChunkManager* chunk_manager = vs_list()->chunk_manager();
1979 chunk_manager->slow_locked_verify();
1981 if (TraceMetadataChunkAllocation && Verbose) {
1982 gclog_or_tty->print_cr("~SpaceManager(): " PTR_FORMAT, this);
1983 locked_print_chunks_in_use_on(gclog_or_tty);
1984 }
1986 // Mangle freed memory.
1987 NOT_PRODUCT(mangle_freed_chunks();)
1989 // Have to update before the chunks_in_use lists are emptied
1990 // below.
1991 chunk_manager->inc_free_chunks_total(in_use_before,
1992 sum_count_in_chunks_in_use());
1994 // Add all the chunks in use by this space manager
1995 // to the global list of free chunks.
1997 // Follow each list of chunks-in-use and add them to the
1998 // free lists. Each list is NULL terminated.
2000 for (ChunkIndex i = ZeroIndex; i < HumongousIndex; i = next_chunk_index(i)) {
2001 if (TraceMetadataChunkAllocation && Verbose) {
2002 gclog_or_tty->print_cr("returned %d %s chunks to freelist",
2003 sum_count_in_chunks_in_use(i),
2004 chunk_size_name(i));
2005 }
2006 Metachunk* chunks = chunks_in_use(i);
2007 chunk_manager->free_chunks(i)->add_at_head(chunks);
2008 set_chunks_in_use(i, NULL);
2009 if (TraceMetadataChunkAllocation && Verbose) {
2010 gclog_or_tty->print_cr("updated freelist count %d %s",
2011 chunk_manager->free_chunks(i)->sum_list_count(),
2012 chunk_size_name(i));
2013 }
2014 assert(i != HumongousIndex, "Humongous chunks are handled explicitly later");
2015 }
2017 // The medium chunk case may be optimized by passing the head and
2018 // tail of the medium chunk list to add_at_head(). The tail is often
2019 // the current chunk but there are probably exceptions.
2021 // Humongous chunks
2022 if (TraceMetadataChunkAllocation && Verbose) {
2023 gclog_or_tty->print_cr("returned %d %s humongous chunks to dictionary",
2024 sum_count_in_chunks_in_use(HumongousIndex),
2025 chunk_size_name(HumongousIndex));
2026 gclog_or_tty->print("Humongous chunk dictionary: ");
2027 }
2028 // Humongous chunks are never the current chunk.
2029 Metachunk* humongous_chunks = chunks_in_use(HumongousIndex);
2031 while (humongous_chunks != NULL) {
2032 #ifdef ASSERT
2033 humongous_chunks->set_is_free(true);
2034 #endif
2035 if (TraceMetadataChunkAllocation && Verbose) {
2036 gclog_or_tty->print(PTR_FORMAT " (" SIZE_FORMAT ") ",
2037 humongous_chunks,
2038 humongous_chunks->word_size());
2039 }
2040 assert(humongous_chunks->word_size() == (size_t)
2041 align_size_up(humongous_chunks->word_size(),
2042 HumongousChunkGranularity),
2043 err_msg("Humongous chunk size is wrong: word size " SIZE_FORMAT
2044 " granularity %d",
2045 humongous_chunks->word_size(), HumongousChunkGranularity));
2046 Metachunk* next_humongous_chunks = humongous_chunks->next();
2047 chunk_manager->humongous_dictionary()->return_chunk(humongous_chunks);
2048 humongous_chunks = next_humongous_chunks;
2049 }
2050 if (TraceMetadataChunkAllocation && Verbose) {
2051 gclog_or_tty->print_cr("");
2052 gclog_or_tty->print_cr("updated dictionary count %d %s",
2053 chunk_manager->humongous_dictionary()->total_count(),
2054 chunk_size_name(HumongousIndex));
2055 }
2056 set_chunks_in_use(HumongousIndex, NULL);
2057 chunk_manager->slow_locked_verify();
2058 }
2060 const char* SpaceManager::chunk_size_name(ChunkIndex index) const {
2061 switch (index) {
2062 case SpecializedIndex:
2063 return "Specialized";
2064 case SmallIndex:
2065 return "Small";
2066 case MediumIndex:
2067 return "Medium";
2068 case HumongousIndex:
2069 return "Humongous";
2070 default:
2071 return NULL;
2072 }
2073 }
2075 ChunkIndex ChunkManager::list_index(size_t size) {
2076 switch (size) {
2077 case SpecializedChunk:
2078 assert(SpecializedChunk == ClassSpecializedChunk,
2079 "Need branch for ClassSpecializedChunk");
2080 return SpecializedIndex;
2081 case SmallChunk:
2082 case ClassSmallChunk:
2083 return SmallIndex;
2084 case MediumChunk:
2085 case ClassMediumChunk:
2086 return MediumIndex;
2087 default:
2088 assert(size > MediumChunk || size > ClassMediumChunk,
2089 "Not a humongous chunk");
2090 return HumongousIndex;
2091 }
2092 }
2094 void SpaceManager::deallocate(MetaWord* p, size_t word_size) {
2095 assert_lock_strong(_lock);
2096 size_t min_size = TreeChunk<Metablock, FreeList>::min_size();
2097 assert(word_size >= min_size,
2098 err_msg("Should not deallocate dark matter " SIZE_FORMAT, word_size));
2099 block_freelists()->return_block(p, word_size);
2100 }
2102 // Adds a chunk to the list of chunks in use.
2103 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) {
2105 assert(new_chunk != NULL, "Should not be NULL");
2106 assert(new_chunk->next() == NULL, "Should not be on a list");
2108 new_chunk->reset_empty();
2110 // Find the correct list and and set the current
2111 // chunk for that list.
2112 ChunkIndex index = ChunkManager::list_index(new_chunk->word_size());
2114 if (index != HumongousIndex) {
2115 set_current_chunk(new_chunk);
2116 new_chunk->set_next(chunks_in_use(index));
2117 set_chunks_in_use(index, new_chunk);
2118 } else {
2119 // For null class loader data and DumpSharedSpaces, the first chunk isn't
2120 // small, so small will be null. Link this first chunk as the current
2121 // chunk.
2122 if (make_current) {
2123 // Set as the current chunk but otherwise treat as a humongous chunk.
2124 set_current_chunk(new_chunk);
2125 }
2126 // Link at head. The _current_chunk only points to a humongous chunk for
2127 // the null class loader metaspace (class and data virtual space managers)
2128 // any humongous chunks so will not point to the tail
2129 // of the humongous chunks list.
2130 new_chunk->set_next(chunks_in_use(HumongousIndex));
2131 set_chunks_in_use(HumongousIndex, new_chunk);
2133 assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency");
2134 }
2136 assert(new_chunk->is_empty(), "Not ready for reuse");
2137 if (TraceMetadataChunkAllocation && Verbose) {
2138 gclog_or_tty->print("SpaceManager::add_chunk: %d) ",
2139 sum_count_in_chunks_in_use());
2140 new_chunk->print_on(gclog_or_tty);
2141 vs_list()->chunk_manager()->locked_print_free_chunks(tty);
2142 }
2143 }
2145 Metachunk* SpaceManager::get_new_chunk(size_t word_size,
2146 size_t grow_chunks_by_words) {
2148 Metachunk* next = vs_list()->get_new_chunk(word_size,
2149 grow_chunks_by_words,
2150 medium_chunk_bunch());
2152 if (TraceMetadataHumongousAllocation &&
2153 SpaceManager::is_humongous(next->word_size())) {
2154 gclog_or_tty->print_cr(" new humongous chunk word size " PTR_FORMAT,
2155 next->word_size());
2156 }
2158 return next;
2159 }
2161 MetaWord* SpaceManager::allocate(size_t word_size) {
2162 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2164 // If only the dictionary is going to be used (i.e., no
2165 // indexed free list), then there is a minimum size requirement.
2166 // MinChunkSize is a placeholder for the real minimum size JJJ
2167 size_t byte_size = word_size * BytesPerWord;
2169 size_t byte_size_with_overhead = byte_size + Metablock::overhead();
2171 size_t raw_bytes_size = MAX2(byte_size_with_overhead,
2172 Metablock::min_block_byte_size());
2173 raw_bytes_size = ARENA_ALIGN(raw_bytes_size);
2174 size_t raw_word_size = raw_bytes_size / BytesPerWord;
2175 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem");
2177 BlockFreelist* fl = block_freelists();
2178 MetaWord* p = NULL;
2179 // Allocation from the dictionary is expensive in the sense that
2180 // the dictionary has to be searched for a size. Don't allocate
2181 // from the dictionary until it starts to get fat. Is this
2182 // a reasonable policy? Maybe an skinny dictionary is fast enough
2183 // for allocations. Do some profiling. JJJ
2184 if (fl->total_size() > allocation_from_dictionary_limit) {
2185 p = fl->get_block(raw_word_size);
2186 }
2187 if (p == NULL) {
2188 p = allocate_work(raw_word_size);
2189 }
2190 Metadebug::deallocate_block_a_lot(this, raw_word_size);
2192 return p;
2193 }
2195 // Returns the address of spaced allocated for "word_size".
2196 // This methods does not know about blocks (Metablocks)
2197 MetaWord* SpaceManager::allocate_work(size_t word_size) {
2198 assert_lock_strong(_lock);
2199 #ifdef ASSERT
2200 if (Metadebug::test_metadata_failure()) {
2201 return NULL;
2202 }
2203 #endif
2204 // Is there space in the current chunk?
2205 MetaWord* result = NULL;
2207 // For DumpSharedSpaces, only allocate out of the current chunk which is
2208 // never null because we gave it the size we wanted. Caller reports out
2209 // of memory if this returns null.
2210 if (DumpSharedSpaces) {
2211 assert(current_chunk() != NULL, "should never happen");
2212 inc_allocation_total(word_size);
2213 return current_chunk()->allocate(word_size); // caller handles null result
2214 }
2215 if (current_chunk() != NULL) {
2216 result = current_chunk()->allocate(word_size);
2217 }
2219 if (result == NULL) {
2220 result = grow_and_allocate(word_size);
2221 }
2222 if (result > 0) {
2223 inc_allocation_total(word_size);
2224 assert(result != (MetaWord*) chunks_in_use(MediumIndex),
2225 "Head of the list is being allocated");
2226 }
2228 return result;
2229 }
2231 void SpaceManager::verify() {
2232 // If there are blocks in the dictionary, then
2233 // verfication of chunks does not work since
2234 // being in the dictionary alters a chunk.
2235 if (block_freelists()->total_size() == 0) {
2236 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2237 Metachunk* curr = chunks_in_use(i);
2238 while (curr != NULL) {
2239 curr->verify();
2240 verify_chunk_size(curr);
2241 curr = curr->next();
2242 }
2243 }
2244 }
2245 }
2247 void SpaceManager::verify_chunk_size(Metachunk* chunk) {
2248 assert(is_humongous(chunk->word_size()) ||
2249 chunk->word_size() == medium_chunk_size() ||
2250 chunk->word_size() == small_chunk_size() ||
2251 chunk->word_size() == specialized_chunk_size(),
2252 "Chunk size is wrong");
2253 return;
2254 }
2256 #ifdef ASSERT
2257 void SpaceManager::verify_allocation_total() {
2258 // Verification is only guaranteed at a safepoint.
2259 if (SafepointSynchronize::is_at_safepoint()) {
2260 gclog_or_tty->print_cr("Chunk " PTR_FORMAT " allocation_total " SIZE_FORMAT
2261 " sum_used_in_chunks_in_use " SIZE_FORMAT,
2262 this,
2263 allocation_total(),
2264 sum_used_in_chunks_in_use());
2265 }
2266 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2267 assert(allocation_total() == sum_used_in_chunks_in_use(),
2268 err_msg("allocation total is not consistent " SIZE_FORMAT
2269 " vs " SIZE_FORMAT,
2270 allocation_total(), sum_used_in_chunks_in_use()));
2271 }
2273 #endif
2275 void SpaceManager::dump(outputStream* const out) const {
2276 size_t curr_total = 0;
2277 size_t waste = 0;
2278 uint i = 0;
2279 size_t used = 0;
2280 size_t capacity = 0;
2282 // Add up statistics for all chunks in this SpaceManager.
2283 for (ChunkIndex index = ZeroIndex;
2284 index < NumberOfInUseLists;
2285 index = next_chunk_index(index)) {
2286 for (Metachunk* curr = chunks_in_use(index);
2287 curr != NULL;
2288 curr = curr->next()) {
2289 out->print("%d) ", i++);
2290 curr->print_on(out);
2291 if (TraceMetadataChunkAllocation && Verbose) {
2292 block_freelists()->print_on(out);
2293 }
2294 curr_total += curr->word_size();
2295 used += curr->used_word_size();
2296 capacity += curr->capacity_word_size();
2297 waste += curr->free_word_size() + curr->overhead();;
2298 }
2299 }
2301 size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size();
2302 // Free space isn't wasted.
2303 waste -= free;
2305 out->print_cr("total of all chunks " SIZE_FORMAT " used " SIZE_FORMAT
2306 " free " SIZE_FORMAT " capacity " SIZE_FORMAT
2307 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste);
2308 }
2310 #ifndef PRODUCT
2311 void SpaceManager::mangle_freed_chunks() {
2312 for (ChunkIndex index = ZeroIndex;
2313 index < NumberOfInUseLists;
2314 index = next_chunk_index(index)) {
2315 for (Metachunk* curr = chunks_in_use(index);
2316 curr != NULL;
2317 curr = curr->next()) {
2318 curr->mangle();
2319 }
2320 }
2321 }
2322 #endif // PRODUCT
2324 // MetaspaceAux
2326 size_t MetaspaceAux::used_in_bytes(Metaspace::MetadataType mdtype) {
2327 size_t used = 0;
2328 ClassLoaderDataGraphMetaspaceIterator iter;
2329 while (iter.repeat()) {
2330 Metaspace* msp = iter.get_next();
2331 // Sum allocation_total for each metaspace
2332 if (msp != NULL) {
2333 used += msp->used_words(mdtype);
2334 }
2335 }
2336 return used * BytesPerWord;
2337 }
2339 size_t MetaspaceAux::free_in_bytes(Metaspace::MetadataType mdtype) {
2340 size_t free = 0;
2341 ClassLoaderDataGraphMetaspaceIterator iter;
2342 while (iter.repeat()) {
2343 Metaspace* msp = iter.get_next();
2344 if (msp != NULL) {
2345 free += msp->free_words(mdtype);
2346 }
2347 }
2348 return free * BytesPerWord;
2349 }
2351 size_t MetaspaceAux::capacity_in_bytes(Metaspace::MetadataType mdtype) {
2352 size_t capacity = free_chunks_total(mdtype);
2353 ClassLoaderDataGraphMetaspaceIterator iter;
2354 while (iter.repeat()) {
2355 Metaspace* msp = iter.get_next();
2356 if (msp != NULL) {
2357 capacity += msp->capacity_words(mdtype);
2358 }
2359 }
2360 return capacity * BytesPerWord;
2361 }
2363 size_t MetaspaceAux::reserved_in_bytes(Metaspace::MetadataType mdtype) {
2364 size_t reserved = (mdtype == Metaspace::ClassType) ?
2365 Metaspace::class_space_list()->virtual_space_total() :
2366 Metaspace::space_list()->virtual_space_total();
2367 return reserved * BytesPerWord;
2368 }
2370 size_t MetaspaceAux::min_chunk_size() { return Metaspace::first_chunk_word_size(); }
2372 size_t MetaspaceAux::free_chunks_total(Metaspace::MetadataType mdtype) {
2373 ChunkManager* chunk = (mdtype == Metaspace::ClassType) ?
2374 Metaspace::class_space_list()->chunk_manager() :
2375 Metaspace::space_list()->chunk_manager();
2376 chunk->slow_verify();
2377 return chunk->free_chunks_total();
2378 }
2380 size_t MetaspaceAux::free_chunks_total_in_bytes(Metaspace::MetadataType mdtype) {
2381 return free_chunks_total(mdtype) * BytesPerWord;
2382 }
2384 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) {
2385 gclog_or_tty->print(", [Metaspace:");
2386 if (PrintGCDetails && Verbose) {
2387 gclog_or_tty->print(" " SIZE_FORMAT
2388 "->" SIZE_FORMAT
2389 "(" SIZE_FORMAT "/" SIZE_FORMAT ")",
2390 prev_metadata_used,
2391 used_in_bytes(),
2392 capacity_in_bytes(),
2393 reserved_in_bytes());
2394 } else {
2395 gclog_or_tty->print(" " SIZE_FORMAT "K"
2396 "->" SIZE_FORMAT "K"
2397 "(" SIZE_FORMAT "K/" SIZE_FORMAT "K)",
2398 prev_metadata_used / K,
2399 used_in_bytes()/ K,
2400 capacity_in_bytes()/K,
2401 reserved_in_bytes()/ K);
2402 }
2404 gclog_or_tty->print("]");
2405 }
2407 // This is printed when PrintGCDetails
2408 void MetaspaceAux::print_on(outputStream* out) {
2409 Metaspace::MetadataType ct = Metaspace::ClassType;
2410 Metaspace::MetadataType nct = Metaspace::NonClassType;
2412 out->print_cr(" Metaspace total "
2413 SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
2414 " reserved " SIZE_FORMAT "K",
2415 capacity_in_bytes()/K, used_in_bytes()/K, reserved_in_bytes()/K);
2416 out->print_cr(" data space "
2417 SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
2418 " reserved " SIZE_FORMAT "K",
2419 capacity_in_bytes(nct)/K, used_in_bytes(nct)/K, reserved_in_bytes(nct)/K);
2420 out->print_cr(" class space "
2421 SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
2422 " reserved " SIZE_FORMAT "K",
2423 capacity_in_bytes(ct)/K, used_in_bytes(ct)/K, reserved_in_bytes(ct)/K);
2424 }
2426 // Print information for class space and data space separately.
2427 // This is almost the same as above.
2428 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) {
2429 size_t free_chunks_capacity_bytes = free_chunks_total_in_bytes(mdtype);
2430 size_t capacity_bytes = capacity_in_bytes(mdtype);
2431 size_t used_bytes = used_in_bytes(mdtype);
2432 size_t free_bytes = free_in_bytes(mdtype);
2433 size_t used_and_free = used_bytes + free_bytes +
2434 free_chunks_capacity_bytes;
2435 out->print_cr(" Chunk accounting: used in chunks " SIZE_FORMAT
2436 "K + unused in chunks " SIZE_FORMAT "K + "
2437 " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT
2438 "K capacity in allocated chunks " SIZE_FORMAT "K",
2439 used_bytes / K,
2440 free_bytes / K,
2441 free_chunks_capacity_bytes / K,
2442 used_and_free / K,
2443 capacity_bytes / K);
2444 // Accounting can only be correct if we got the values during a safepoint
2445 assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong");
2446 }
2448 // Print total fragmentation for class and data metaspaces separately
2449 void MetaspaceAux::print_waste(outputStream* out) {
2451 size_t specialized_waste = 0, small_waste = 0, medium_waste = 0, large_waste = 0;
2452 size_t specialized_count = 0, small_count = 0, medium_count = 0, large_count = 0;
2453 size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0, cls_large_waste = 0;
2454 size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_large_count = 0;
2456 ClassLoaderDataGraphMetaspaceIterator iter;
2457 while (iter.repeat()) {
2458 Metaspace* msp = iter.get_next();
2459 if (msp != NULL) {
2460 specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2461 specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2462 small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2463 small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex);
2464 medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2465 medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex);
2466 large_waste += msp->vsm()->sum_waste_in_chunks_in_use(HumongousIndex);
2467 large_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2469 cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2470 cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2471 cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2472 cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex);
2473 cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2474 cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex);
2475 cls_large_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(HumongousIndex);
2476 cls_large_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2477 }
2478 }
2479 out->print_cr("Total fragmentation waste (words) doesn't count free space");
2480 out->print_cr(" data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2481 SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
2482 SIZE_FORMAT " medium(s) " SIZE_FORMAT,
2483 specialized_count, specialized_waste, small_count,
2484 small_waste, medium_count, medium_waste);
2485 out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2486 SIZE_FORMAT " small(s) " SIZE_FORMAT,
2487 cls_specialized_count, cls_specialized_waste,
2488 cls_small_count, cls_small_waste);
2489 }
2491 // Dump global metaspace things from the end of ClassLoaderDataGraph
2492 void MetaspaceAux::dump(outputStream* out) {
2493 out->print_cr("All Metaspace:");
2494 out->print("data space: "); print_on(out, Metaspace::NonClassType);
2495 out->print("class space: "); print_on(out, Metaspace::ClassType);
2496 print_waste(out);
2497 }
2499 void MetaspaceAux::verify_free_chunks() {
2500 Metaspace::space_list()->chunk_manager()->verify();
2501 Metaspace::class_space_list()->chunk_manager()->verify();
2502 }
2504 // Metaspace methods
2506 size_t Metaspace::_first_chunk_word_size = 0;
2507 size_t Metaspace::_first_class_chunk_word_size = 0;
2509 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) {
2510 initialize(lock, type);
2511 }
2513 Metaspace::~Metaspace() {
2514 delete _vsm;
2515 delete _class_vsm;
2516 }
2518 VirtualSpaceList* Metaspace::_space_list = NULL;
2519 VirtualSpaceList* Metaspace::_class_space_list = NULL;
2521 #define VIRTUALSPACEMULTIPLIER 2
2523 void Metaspace::global_initialize() {
2524 // Initialize the alignment for shared spaces.
2525 int max_alignment = os::vm_page_size();
2526 MetaspaceShared::set_max_alignment(max_alignment);
2528 if (DumpSharedSpaces) {
2529 SharedReadOnlySize = align_size_up(SharedReadOnlySize, max_alignment);
2530 SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment);
2531 SharedMiscDataSize = align_size_up(SharedMiscDataSize, max_alignment);
2532 SharedMiscCodeSize = align_size_up(SharedMiscCodeSize, max_alignment);
2534 // Initialize with the sum of the shared space sizes. The read-only
2535 // and read write metaspace chunks will be allocated out of this and the
2536 // remainder is the misc code and data chunks.
2537 size_t total = align_size_up(SharedReadOnlySize + SharedReadWriteSize +
2538 SharedMiscDataSize + SharedMiscCodeSize,
2539 os::vm_allocation_granularity());
2540 size_t word_size = total/wordSize;
2541 _space_list = new VirtualSpaceList(word_size);
2542 } else {
2543 // If using shared space, open the file that contains the shared space
2544 // and map in the memory before initializing the rest of metaspace (so
2545 // the addresses don't conflict)
2546 if (UseSharedSpaces) {
2547 FileMapInfo* mapinfo = new FileMapInfo();
2548 memset(mapinfo, 0, sizeof(FileMapInfo));
2550 // Open the shared archive file, read and validate the header. If
2551 // initialization fails, shared spaces [UseSharedSpaces] are
2552 // disabled and the file is closed.
2553 // Map in spaces now also
2554 if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) {
2555 FileMapInfo::set_current_info(mapinfo);
2556 } else {
2557 assert(!mapinfo->is_open() && !UseSharedSpaces,
2558 "archive file not closed or shared spaces not disabled.");
2559 }
2560 }
2562 // Initialize these before initializing the VirtualSpaceList
2563 _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord;
2564 _first_chunk_word_size = align_word_size_up(_first_chunk_word_size);
2565 // Make the first class chunk bigger than a medium chunk so it's not put
2566 // on the medium chunk list. The next chunk will be small and progress
2567 // from there. This size calculated by -version.
2568 _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6,
2569 (ClassMetaspaceSize/BytesPerWord)*2);
2570 _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size);
2571 // Arbitrarily set the initial virtual space to a multiple
2572 // of the boot class loader size.
2573 size_t word_size = VIRTUALSPACEMULTIPLIER * first_chunk_word_size();
2574 // Initialize the list of virtual spaces.
2575 _space_list = new VirtualSpaceList(word_size);
2576 }
2577 }
2579 // For UseCompressedKlassPointers the class space is reserved as a piece of the
2580 // Java heap because the compression algorithm is the same for each. The
2581 // argument passed in is at the top of the compressed space
2582 void Metaspace::initialize_class_space(ReservedSpace rs) {
2583 // The reserved space size may be bigger because of alignment, esp with UseLargePages
2584 assert(rs.size() >= ClassMetaspaceSize,
2585 err_msg(SIZE_FORMAT " != " UINTX_FORMAT, rs.size(), ClassMetaspaceSize));
2586 _class_space_list = new VirtualSpaceList(rs);
2587 }
2589 void Metaspace::initialize(Mutex* lock,
2590 MetaspaceType type) {
2592 assert(space_list() != NULL,
2593 "Metadata VirtualSpaceList has not been initialized");
2595 _vsm = new SpaceManager(lock, space_list());
2596 if (_vsm == NULL) {
2597 return;
2598 }
2599 size_t word_size;
2600 size_t class_word_size;
2601 vsm()->get_initial_chunk_sizes(type,
2602 &word_size,
2603 &class_word_size);
2605 assert(class_space_list() != NULL,
2606 "Class VirtualSpaceList has not been initialized");
2608 // Allocate SpaceManager for classes.
2609 _class_vsm = new SpaceManager(lock, class_space_list());
2610 if (_class_vsm == NULL) {
2611 return;
2612 }
2614 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
2616 // Allocate chunk for metadata objects
2617 Metachunk* new_chunk =
2618 space_list()->get_initialization_chunk(word_size,
2619 vsm()->medium_chunk_bunch());
2620 assert(!DumpSharedSpaces || new_chunk != NULL, "should have enough space for both chunks");
2621 if (new_chunk != NULL) {
2622 // Add to this manager's list of chunks in use and current_chunk().
2623 vsm()->add_chunk(new_chunk, true);
2624 }
2626 // Allocate chunk for class metadata objects
2627 Metachunk* class_chunk =
2628 class_space_list()->get_initialization_chunk(class_word_size,
2629 class_vsm()->medium_chunk_bunch());
2630 if (class_chunk != NULL) {
2631 class_vsm()->add_chunk(class_chunk, true);
2632 }
2633 }
2635 size_t Metaspace::align_word_size_up(size_t word_size) {
2636 size_t byte_size = word_size * wordSize;
2637 return ReservedSpace::allocation_align_size_up(byte_size) / wordSize;
2638 }
2640 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) {
2641 // DumpSharedSpaces doesn't use class metadata area (yet)
2642 if (mdtype == ClassType && !DumpSharedSpaces) {
2643 return class_vsm()->allocate(word_size);
2644 } else {
2645 return vsm()->allocate(word_size);
2646 }
2647 }
2649 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) {
2650 MetaWord* result;
2651 MetaspaceGC::set_expand_after_GC(true);
2652 size_t before_inc = MetaspaceGC::capacity_until_GC();
2653 size_t delta_words = MetaspaceGC::delta_capacity_until_GC(word_size);
2654 MetaspaceGC::inc_capacity_until_GC(delta_words);
2655 if (PrintGCDetails && Verbose) {
2656 gclog_or_tty->print_cr("Increase capacity to GC from " SIZE_FORMAT
2657 " to " SIZE_FORMAT, before_inc, MetaspaceGC::capacity_until_GC());
2658 }
2660 result = allocate(word_size, mdtype);
2662 return result;
2663 }
2665 // Space allocated in the Metaspace. This may
2666 // be across several metadata virtual spaces.
2667 char* Metaspace::bottom() const {
2668 assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces");
2669 return (char*)vsm()->current_chunk()->bottom();
2670 }
2672 size_t Metaspace::used_words(MetadataType mdtype) const {
2673 // return vsm()->allocation_total();
2674 return mdtype == ClassType ? class_vsm()->sum_used_in_chunks_in_use() :
2675 vsm()->sum_used_in_chunks_in_use(); // includes overhead!
2676 }
2678 size_t Metaspace::free_words(MetadataType mdtype) const {
2679 return mdtype == ClassType ? class_vsm()->sum_free_in_chunks_in_use() :
2680 vsm()->sum_free_in_chunks_in_use();
2681 }
2683 // Space capacity in the Metaspace. It includes
2684 // space in the list of chunks from which allocations
2685 // have been made. Don't include space in the global freelist and
2686 // in the space available in the dictionary which
2687 // is already counted in some chunk.
2688 size_t Metaspace::capacity_words(MetadataType mdtype) const {
2689 return mdtype == ClassType ? class_vsm()->sum_capacity_in_chunks_in_use() :
2690 vsm()->sum_capacity_in_chunks_in_use();
2691 }
2693 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
2694 if (SafepointSynchronize::is_at_safepoint()) {
2695 assert(Thread::current()->is_VM_thread(), "should be the VM thread");
2696 // Don't take Heap_lock
2697 MutexLocker ml(vsm()->lock());
2698 if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
2699 // Dark matter. Too small for dictionary.
2700 #ifdef ASSERT
2701 Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
2702 #endif
2703 return;
2704 }
2705 if (is_class) {
2706 class_vsm()->deallocate(ptr, word_size);
2707 } else {
2708 vsm()->deallocate(ptr, word_size);
2709 }
2710 } else {
2711 MutexLocker ml(vsm()->lock());
2713 if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
2714 // Dark matter. Too small for dictionary.
2715 #ifdef ASSERT
2716 Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
2717 #endif
2718 return;
2719 }
2720 if (is_class) {
2721 class_vsm()->deallocate(ptr, word_size);
2722 } else {
2723 vsm()->deallocate(ptr, word_size);
2724 }
2725 }
2726 }
2728 Metablock* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size,
2729 bool read_only, MetadataType mdtype, TRAPS) {
2730 if (HAS_PENDING_EXCEPTION) {
2731 assert(false, "Should not allocate with exception pending");
2732 return NULL; // caller does a CHECK_NULL too
2733 }
2735 // SSS: Should we align the allocations and make sure the sizes are aligned.
2736 MetaWord* result = NULL;
2738 assert(loader_data != NULL, "Should never pass around a NULL loader_data. "
2739 "ClassLoaderData::the_null_class_loader_data() should have been used.");
2740 // Allocate in metaspaces without taking out a lock, because it deadlocks
2741 // with the SymbolTable_lock. Dumping is single threaded for now. We'll have
2742 // to revisit this for application class data sharing.
2743 if (DumpSharedSpaces) {
2744 if (read_only) {
2745 result = loader_data->ro_metaspace()->allocate(word_size, NonClassType);
2746 } else {
2747 result = loader_data->rw_metaspace()->allocate(word_size, NonClassType);
2748 }
2749 if (result == NULL) {
2750 report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite);
2751 }
2752 return Metablock::initialize(result, word_size);
2753 }
2755 result = loader_data->metaspace_non_null()->allocate(word_size, mdtype);
2757 if (result == NULL) {
2758 // Try to clean out some memory and retry.
2759 result =
2760 Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation(
2761 loader_data, word_size, mdtype);
2763 // If result is still null, we are out of memory.
2764 if (result == NULL) {
2765 if (Verbose && TraceMetadataChunkAllocation) {
2766 gclog_or_tty->print_cr("Metaspace allocation failed for size "
2767 SIZE_FORMAT, word_size);
2768 if (loader_data->metaspace_or_null() != NULL) loader_data->metaspace_or_null()->dump(gclog_or_tty);
2769 MetaspaceAux::dump(gclog_or_tty);
2770 }
2771 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
2772 report_java_out_of_memory("Metadata space");
2774 if (JvmtiExport::should_post_resource_exhausted()) {
2775 JvmtiExport::post_resource_exhausted(
2776 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
2777 "Metadata space");
2778 }
2779 THROW_OOP_0(Universe::out_of_memory_error_perm_gen());
2780 }
2781 }
2782 return Metablock::initialize(result, word_size);
2783 }
2785 void Metaspace::print_on(outputStream* out) const {
2786 // Print both class virtual space counts and metaspace.
2787 if (Verbose) {
2788 vsm()->print_on(out);
2789 class_vsm()->print_on(out);
2790 }
2791 }
2793 bool Metaspace::contains(const void * ptr) {
2794 if (MetaspaceShared::is_in_shared_space(ptr)) {
2795 return true;
2796 }
2797 // This is checked while unlocked. As long as the virtualspaces are added
2798 // at the end, the pointer will be in one of them. The virtual spaces
2799 // aren't deleted presently. When they are, some sort of locking might
2800 // be needed. Note, locking this can cause inversion problems with the
2801 // caller in MetaspaceObj::is_metadata() function.
2802 return space_list()->contains(ptr) || class_space_list()->contains(ptr);
2803 }
2805 void Metaspace::verify() {
2806 vsm()->verify();
2807 class_vsm()->verify();
2808 }
2810 void Metaspace::dump(outputStream* const out) const {
2811 if (UseMallocOnly) {
2812 // Just print usage for now
2813 out->print_cr("usage %d", used_words(Metaspace::NonClassType));
2814 }
2815 out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, vsm());
2816 vsm()->dump(out);
2817 out->print_cr("\nClass space manager: " INTPTR_FORMAT, class_vsm());
2818 class_vsm()->dump(out);
2819 }