Mon, 01 Apr 2013 10:50:30 -0700
8011173: NPG: Replace the ChunkList implementation with class FreeList<Metachunk>
Reviewed-by: mgerdin, tschatzl, johnc, coleenp
1 /*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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 typedef class FreeList<Metachunk> ChunkList;
108 // Manages the global free lists of chunks.
109 // Has three lists of free chunks, and a total size and
110 // count that includes all three
112 class ChunkManager VALUE_OBJ_CLASS_SPEC {
114 // Free list of chunks of different sizes.
115 // SmallChunk
116 // MediumChunk
117 // HumongousChunk
118 ChunkList _free_chunks[NumberOfFreeLists];
121 // HumongousChunk
122 ChunkTreeDictionary _humongous_dictionary;
124 // ChunkManager in all lists of this type
125 size_t _free_chunks_total;
126 size_t _free_chunks_count;
128 void dec_free_chunks_total(size_t v) {
129 assert(_free_chunks_count > 0 &&
130 _free_chunks_total > 0,
131 "About to go negative");
132 Atomic::add_ptr(-1, &_free_chunks_count);
133 jlong minus_v = (jlong) - (jlong) v;
134 Atomic::add_ptr(minus_v, &_free_chunks_total);
135 }
137 // Debug support
139 size_t sum_free_chunks();
140 size_t sum_free_chunks_count();
142 void locked_verify_free_chunks_total();
143 void slow_locked_verify_free_chunks_total() {
144 if (metaspace_slow_verify) {
145 locked_verify_free_chunks_total();
146 }
147 }
148 void locked_verify_free_chunks_count();
149 void slow_locked_verify_free_chunks_count() {
150 if (metaspace_slow_verify) {
151 locked_verify_free_chunks_count();
152 }
153 }
154 void verify_free_chunks_count();
156 public:
158 ChunkManager() : _free_chunks_total(0), _free_chunks_count(0) {}
160 // add or delete (return) a chunk to the global freelist.
161 Metachunk* chunk_freelist_allocate(size_t word_size);
162 void chunk_freelist_deallocate(Metachunk* chunk);
164 // Map a size to a list index assuming that there are lists
165 // for special, small, medium, and humongous chunks.
166 static ChunkIndex list_index(size_t size);
168 // Add the simple linked list of chunks to the freelist of chunks
169 // of type index.
170 void return_chunks(ChunkIndex index, Metachunk* chunks);
172 // Total of the space in the free chunks list
173 size_t free_chunks_total();
174 size_t free_chunks_total_in_bytes();
176 // Number of chunks in the free chunks list
177 size_t free_chunks_count();
179 void inc_free_chunks_total(size_t v, size_t count = 1) {
180 Atomic::add_ptr(count, &_free_chunks_count);
181 Atomic::add_ptr(v, &_free_chunks_total);
182 }
183 ChunkTreeDictionary* humongous_dictionary() {
184 return &_humongous_dictionary;
185 }
187 ChunkList* free_chunks(ChunkIndex index);
189 // Returns the list for the given chunk word size.
190 ChunkList* find_free_chunks_list(size_t word_size);
192 // Add and remove from a list by size. Selects
193 // list based on size of chunk.
194 void free_chunks_put(Metachunk* chuck);
195 Metachunk* free_chunks_get(size_t chunk_word_size);
197 // Debug support
198 void verify();
199 void slow_verify() {
200 if (metaspace_slow_verify) {
201 verify();
202 }
203 }
204 void locked_verify();
205 void slow_locked_verify() {
206 if (metaspace_slow_verify) {
207 locked_verify();
208 }
209 }
210 void verify_free_chunks_total();
212 void locked_print_free_chunks(outputStream* st);
213 void locked_print_sum_free_chunks(outputStream* st);
215 void print_on(outputStream* st);
216 };
219 // Used to manage the free list of Metablocks (a block corresponds
220 // to the allocation of a quantum of metadata).
221 class BlockFreelist VALUE_OBJ_CLASS_SPEC {
222 BlockTreeDictionary* _dictionary;
223 static Metablock* initialize_free_chunk(MetaWord* p, size_t word_size);
225 // Accessors
226 BlockTreeDictionary* dictionary() const { return _dictionary; }
228 public:
229 BlockFreelist();
230 ~BlockFreelist();
232 // Get and return a block to the free list
233 MetaWord* get_block(size_t word_size);
234 void return_block(MetaWord* p, size_t word_size);
236 size_t total_size() {
237 if (dictionary() == NULL) {
238 return 0;
239 } else {
240 return dictionary()->total_size();
241 }
242 }
244 void print_on(outputStream* st) const;
245 };
247 class VirtualSpaceNode : public CHeapObj<mtClass> {
248 friend class VirtualSpaceList;
250 // Link to next VirtualSpaceNode
251 VirtualSpaceNode* _next;
253 // total in the VirtualSpace
254 MemRegion _reserved;
255 ReservedSpace _rs;
256 VirtualSpace _virtual_space;
257 MetaWord* _top;
259 // Convenience functions for logical bottom and end
260 MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); }
261 MetaWord* end() const { return (MetaWord*) _virtual_space.high(); }
263 // Convenience functions to access the _virtual_space
264 char* low() const { return virtual_space()->low(); }
265 char* high() const { return virtual_space()->high(); }
267 public:
269 VirtualSpaceNode(size_t byte_size);
270 VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs) {}
271 ~VirtualSpaceNode();
273 // address of next available space in _virtual_space;
274 // Accessors
275 VirtualSpaceNode* next() { return _next; }
276 void set_next(VirtualSpaceNode* v) { _next = v; }
278 void set_reserved(MemRegion const v) { _reserved = v; }
279 void set_top(MetaWord* v) { _top = v; }
281 // Accessors
282 MemRegion* reserved() { return &_reserved; }
283 VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; }
285 // Returns true if "word_size" is available in the virtual space
286 bool is_available(size_t word_size) { return _top + word_size <= end(); }
288 MetaWord* top() const { return _top; }
289 void inc_top(size_t word_size) { _top += word_size; }
291 // used and capacity in this single entry in the list
292 size_t used_words_in_vs() const;
293 size_t capacity_words_in_vs() const;
295 bool initialize();
297 // get space from the virtual space
298 Metachunk* take_from_committed(size_t chunk_word_size);
300 // Allocate a chunk from the virtual space and return it.
301 Metachunk* get_chunk_vs(size_t chunk_word_size);
302 Metachunk* get_chunk_vs_with_expand(size_t chunk_word_size);
304 // Expands/shrinks the committed space in a virtual space. Delegates
305 // to Virtualspace
306 bool expand_by(size_t words, bool pre_touch = false);
307 bool shrink_by(size_t words);
309 #ifdef ASSERT
310 // Debug support
311 static void verify_virtual_space_total();
312 static void verify_virtual_space_count();
313 void mangle();
314 #endif
316 void print_on(outputStream* st) const;
317 };
319 // byte_size is the size of the associated virtualspace.
320 VirtualSpaceNode::VirtualSpaceNode(size_t byte_size) : _top(NULL), _next(NULL), _rs(0) {
321 // align up to vm allocation granularity
322 byte_size = align_size_up(byte_size, os::vm_allocation_granularity());
324 // This allocates memory with mmap. For DumpSharedspaces, try to reserve
325 // configurable address, generally at the top of the Java heap so other
326 // memory addresses don't conflict.
327 if (DumpSharedSpaces) {
328 char* shared_base = (char*)SharedBaseAddress;
329 _rs = ReservedSpace(byte_size, 0, false, shared_base, 0);
330 if (_rs.is_reserved()) {
331 assert(shared_base == 0 || _rs.base() == shared_base, "should match");
332 } else {
333 // Get a mmap region anywhere if the SharedBaseAddress fails.
334 _rs = ReservedSpace(byte_size);
335 }
336 MetaspaceShared::set_shared_rs(&_rs);
337 } else {
338 _rs = ReservedSpace(byte_size);
339 }
341 MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass);
342 }
344 // List of VirtualSpaces for metadata allocation.
345 // It has a _next link for singly linked list and a MemRegion
346 // for total space in the VirtualSpace.
347 class VirtualSpaceList : public CHeapObj<mtClass> {
348 friend class VirtualSpaceNode;
350 enum VirtualSpaceSizes {
351 VirtualSpaceSize = 256 * K
352 };
354 // Global list of virtual spaces
355 // Head of the list
356 VirtualSpaceNode* _virtual_space_list;
357 // virtual space currently being used for allocations
358 VirtualSpaceNode* _current_virtual_space;
359 // Free chunk list for all other metadata
360 ChunkManager _chunk_manager;
362 // Can this virtual list allocate >1 spaces? Also, used to determine
363 // whether to allocate unlimited small chunks in this virtual space
364 bool _is_class;
365 bool can_grow() const { return !is_class() || !UseCompressedKlassPointers; }
367 // Sum of space in all virtual spaces and number of virtual spaces
368 size_t _virtual_space_total;
369 size_t _virtual_space_count;
371 ~VirtualSpaceList();
373 VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; }
375 void set_virtual_space_list(VirtualSpaceNode* v) {
376 _virtual_space_list = v;
377 }
378 void set_current_virtual_space(VirtualSpaceNode* v) {
379 _current_virtual_space = v;
380 }
382 void link_vs(VirtualSpaceNode* new_entry, size_t vs_word_size);
384 // Get another virtual space and add it to the list. This
385 // is typically prompted by a failed attempt to allocate a chunk
386 // and is typically followed by the allocation of a chunk.
387 bool grow_vs(size_t vs_word_size);
389 public:
390 VirtualSpaceList(size_t word_size);
391 VirtualSpaceList(ReservedSpace rs);
393 Metachunk* get_new_chunk(size_t word_size,
394 size_t grow_chunks_by_words,
395 size_t medium_chunk_bunch);
397 // Get the first chunk for a Metaspace. Used for
398 // special cases such as the boot class loader, reflection
399 // class loader and anonymous class loader.
400 Metachunk* get_initialization_chunk(size_t word_size, size_t chunk_bunch);
402 VirtualSpaceNode* current_virtual_space() {
403 return _current_virtual_space;
404 }
406 ChunkManager* chunk_manager() { return &_chunk_manager; }
407 bool is_class() const { return _is_class; }
409 // Allocate the first virtualspace.
410 void initialize(size_t word_size);
412 size_t virtual_space_total() { return _virtual_space_total; }
413 void inc_virtual_space_total(size_t v) {
414 Atomic::add_ptr(v, &_virtual_space_total);
415 }
417 size_t virtual_space_count() { return _virtual_space_count; }
418 void inc_virtual_space_count() {
419 Atomic::inc_ptr(&_virtual_space_count);
420 }
422 // Used and capacity in the entire list of virtual spaces.
423 // These are global values shared by all Metaspaces
424 size_t capacity_words_sum();
425 size_t capacity_bytes_sum() { return capacity_words_sum() * BytesPerWord; }
426 size_t used_words_sum();
427 size_t used_bytes_sum() { return used_words_sum() * BytesPerWord; }
429 bool contains(const void *ptr);
431 void print_on(outputStream* st) const;
433 class VirtualSpaceListIterator : public StackObj {
434 VirtualSpaceNode* _virtual_spaces;
435 public:
436 VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) :
437 _virtual_spaces(virtual_spaces) {}
439 bool repeat() {
440 return _virtual_spaces != NULL;
441 }
443 VirtualSpaceNode* get_next() {
444 VirtualSpaceNode* result = _virtual_spaces;
445 if (_virtual_spaces != NULL) {
446 _virtual_spaces = _virtual_spaces->next();
447 }
448 return result;
449 }
450 };
451 };
453 class Metadebug : AllStatic {
454 // Debugging support for Metaspaces
455 static int _deallocate_block_a_lot_count;
456 static int _deallocate_chunk_a_lot_count;
457 static int _allocation_fail_alot_count;
459 public:
460 static int deallocate_block_a_lot_count() {
461 return _deallocate_block_a_lot_count;
462 }
463 static void set_deallocate_block_a_lot_count(int v) {
464 _deallocate_block_a_lot_count = v;
465 }
466 static void inc_deallocate_block_a_lot_count() {
467 _deallocate_block_a_lot_count++;
468 }
469 static int deallocate_chunk_a_lot_count() {
470 return _deallocate_chunk_a_lot_count;
471 }
472 static void reset_deallocate_chunk_a_lot_count() {
473 _deallocate_chunk_a_lot_count = 1;
474 }
475 static void inc_deallocate_chunk_a_lot_count() {
476 _deallocate_chunk_a_lot_count++;
477 }
479 static void init_allocation_fail_alot_count();
480 #ifdef ASSERT
481 static bool test_metadata_failure();
482 #endif
484 static void deallocate_chunk_a_lot(SpaceManager* sm,
485 size_t chunk_word_size);
486 static void deallocate_block_a_lot(SpaceManager* sm,
487 size_t chunk_word_size);
489 };
491 int Metadebug::_deallocate_block_a_lot_count = 0;
492 int Metadebug::_deallocate_chunk_a_lot_count = 0;
493 int Metadebug::_allocation_fail_alot_count = 0;
495 // SpaceManager - used by Metaspace to handle allocations
496 class SpaceManager : public CHeapObj<mtClass> {
497 friend class Metaspace;
498 friend class Metadebug;
500 private:
502 // protects allocations and contains.
503 Mutex* const _lock;
505 // Chunk related size
506 size_t _medium_chunk_bunch;
508 // List of chunks in use by this SpaceManager. Allocations
509 // are done from the current chunk. The list is used for deallocating
510 // chunks when the SpaceManager is freed.
511 Metachunk* _chunks_in_use[NumberOfInUseLists];
512 Metachunk* _current_chunk;
514 // Virtual space where allocation comes from.
515 VirtualSpaceList* _vs_list;
517 // Number of small chunks to allocate to a manager
518 // If class space manager, small chunks are unlimited
519 static uint const _small_chunk_limit;
520 bool has_small_chunk_limit() { return !vs_list()->is_class(); }
522 // Sum of all space in allocated chunks
523 size_t _allocation_total;
525 // Free lists of blocks are per SpaceManager since they
526 // are assumed to be in chunks in use by the SpaceManager
527 // and all chunks in use by a SpaceManager are freed when
528 // the class loader using the SpaceManager is collected.
529 BlockFreelist _block_freelists;
531 // protects virtualspace and chunk expansions
532 static const char* _expand_lock_name;
533 static const int _expand_lock_rank;
534 static Mutex* const _expand_lock;
536 private:
537 // Accessors
538 Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; }
539 void set_chunks_in_use(ChunkIndex index, Metachunk* v) { _chunks_in_use[index] = v; }
541 BlockFreelist* block_freelists() const {
542 return (BlockFreelist*) &_block_freelists;
543 }
545 VirtualSpaceList* vs_list() const { return _vs_list; }
547 Metachunk* current_chunk() const { return _current_chunk; }
548 void set_current_chunk(Metachunk* v) {
549 _current_chunk = v;
550 }
552 Metachunk* find_current_chunk(size_t word_size);
554 // Add chunk to the list of chunks in use
555 void add_chunk(Metachunk* v, bool make_current);
557 Mutex* lock() const { return _lock; }
559 const char* chunk_size_name(ChunkIndex index) const;
561 protected:
562 void initialize();
564 public:
565 SpaceManager(Mutex* lock,
566 VirtualSpaceList* vs_list);
567 ~SpaceManager();
569 enum ChunkMultiples {
570 MediumChunkMultiple = 4
571 };
573 // Accessors
574 size_t specialized_chunk_size() { return SpecializedChunk; }
575 size_t small_chunk_size() { return (size_t) vs_list()->is_class() ? ClassSmallChunk : SmallChunk; }
576 size_t medium_chunk_size() { return (size_t) vs_list()->is_class() ? ClassMediumChunk : MediumChunk; }
577 size_t medium_chunk_bunch() { return medium_chunk_size() * MediumChunkMultiple; }
579 size_t allocation_total() const { return _allocation_total; }
580 void inc_allocation_total(size_t v) { Atomic::add_ptr(v, &_allocation_total); }
581 bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); }
583 static Mutex* expand_lock() { return _expand_lock; }
585 // Set the sizes for the initial chunks.
586 void get_initial_chunk_sizes(Metaspace::MetaspaceType type,
587 size_t* chunk_word_size,
588 size_t* class_chunk_word_size);
590 size_t sum_capacity_in_chunks_in_use() const;
591 size_t sum_used_in_chunks_in_use() const;
592 size_t sum_free_in_chunks_in_use() const;
593 size_t sum_waste_in_chunks_in_use() const;
594 size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const;
596 size_t sum_count_in_chunks_in_use();
597 size_t sum_count_in_chunks_in_use(ChunkIndex i);
599 Metachunk* get_new_chunk(size_t word_size, size_t grow_chunks_by_words);
601 // Block allocation and deallocation.
602 // Allocates a block from the current chunk
603 MetaWord* allocate(size_t word_size);
605 // Helper for allocations
606 MetaWord* allocate_work(size_t word_size);
608 // Returns a block to the per manager freelist
609 void deallocate(MetaWord* p, size_t word_size);
611 // Based on the allocation size and a minimum chunk size,
612 // returned chunk size (for expanding space for chunk allocation).
613 size_t calc_chunk_size(size_t allocation_word_size);
615 // Called when an allocation from the current chunk fails.
616 // Gets a new chunk (may require getting a new virtual space),
617 // and allocates from that chunk.
618 MetaWord* grow_and_allocate(size_t word_size);
620 // debugging support.
622 void dump(outputStream* const out) const;
623 void print_on(outputStream* st) const;
624 void locked_print_chunks_in_use_on(outputStream* st) const;
626 void verify();
627 void verify_chunk_size(Metachunk* chunk);
628 NOT_PRODUCT(void mangle_freed_chunks();)
629 #ifdef ASSERT
630 void verify_allocation_total();
631 #endif
632 };
634 uint const SpaceManager::_small_chunk_limit = 4;
636 const char* SpaceManager::_expand_lock_name =
637 "SpaceManager chunk allocation lock";
638 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1;
639 Mutex* const SpaceManager::_expand_lock =
640 new Mutex(SpaceManager::_expand_lock_rank,
641 SpaceManager::_expand_lock_name,
642 Mutex::_allow_vm_block_flag);
644 // BlockFreelist methods
646 BlockFreelist::BlockFreelist() : _dictionary(NULL) {}
648 BlockFreelist::~BlockFreelist() {
649 if (_dictionary != NULL) {
650 if (Verbose && TraceMetadataChunkAllocation) {
651 _dictionary->print_free_lists(gclog_or_tty);
652 }
653 delete _dictionary;
654 }
655 }
657 Metablock* BlockFreelist::initialize_free_chunk(MetaWord* p, size_t word_size) {
658 Metablock* block = (Metablock*) p;
659 block->set_word_size(word_size);
660 block->set_prev(NULL);
661 block->set_next(NULL);
663 return block;
664 }
666 void BlockFreelist::return_block(MetaWord* p, size_t word_size) {
667 Metablock* free_chunk = initialize_free_chunk(p, word_size);
668 if (dictionary() == NULL) {
669 _dictionary = new BlockTreeDictionary();
670 }
671 dictionary()->return_chunk(free_chunk);
672 }
674 MetaWord* BlockFreelist::get_block(size_t word_size) {
675 if (dictionary() == NULL) {
676 return NULL;
677 }
679 if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
680 // Dark matter. Too small for dictionary.
681 return NULL;
682 }
684 Metablock* free_block =
685 dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::exactly);
686 if (free_block == NULL) {
687 return NULL;
688 }
690 return (MetaWord*) free_block;
691 }
693 void BlockFreelist::print_on(outputStream* st) const {
694 if (dictionary() == NULL) {
695 return;
696 }
697 dictionary()->print_free_lists(st);
698 }
700 // VirtualSpaceNode methods
702 VirtualSpaceNode::~VirtualSpaceNode() {
703 _rs.release();
704 }
706 size_t VirtualSpaceNode::used_words_in_vs() const {
707 return pointer_delta(top(), bottom(), sizeof(MetaWord));
708 }
710 // Space committed in the VirtualSpace
711 size_t VirtualSpaceNode::capacity_words_in_vs() const {
712 return pointer_delta(end(), bottom(), sizeof(MetaWord));
713 }
716 // Allocates the chunk from the virtual space only.
717 // This interface is also used internally for debugging. Not all
718 // chunks removed here are necessarily used for allocation.
719 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) {
720 // Bottom of the new chunk
721 MetaWord* chunk_limit = top();
722 assert(chunk_limit != NULL, "Not safe to call this method");
724 if (!is_available(chunk_word_size)) {
725 if (TraceMetadataChunkAllocation) {
726 tty->print("VirtualSpaceNode::take_from_committed() not available %d words ", chunk_word_size);
727 // Dump some information about the virtual space that is nearly full
728 print_on(tty);
729 }
730 return NULL;
731 }
733 // Take the space (bump top on the current virtual space).
734 inc_top(chunk_word_size);
736 // Point the chunk at the space
737 Metachunk* result = Metachunk::initialize(chunk_limit, chunk_word_size);
738 return result;
739 }
742 // Expand the virtual space (commit more of the reserved space)
743 bool VirtualSpaceNode::expand_by(size_t words, bool pre_touch) {
744 size_t bytes = words * BytesPerWord;
745 bool result = virtual_space()->expand_by(bytes, pre_touch);
746 if (TraceMetavirtualspaceAllocation && !result) {
747 gclog_or_tty->print_cr("VirtualSpaceNode::expand_by() failed "
748 "for byte size " SIZE_FORMAT, bytes);
749 virtual_space()->print();
750 }
751 return result;
752 }
754 // Shrink the virtual space (commit more of the reserved space)
755 bool VirtualSpaceNode::shrink_by(size_t words) {
756 size_t bytes = words * BytesPerWord;
757 virtual_space()->shrink_by(bytes);
758 return true;
759 }
761 // Add another chunk to the chunk list.
763 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) {
764 assert_lock_strong(SpaceManager::expand_lock());
765 Metachunk* result = NULL;
767 return take_from_committed(chunk_word_size);
768 }
770 Metachunk* VirtualSpaceNode::get_chunk_vs_with_expand(size_t chunk_word_size) {
771 assert_lock_strong(SpaceManager::expand_lock());
773 Metachunk* new_chunk = get_chunk_vs(chunk_word_size);
775 if (new_chunk == NULL) {
776 // Only a small part of the virtualspace is committed when first
777 // allocated so committing more here can be expected.
778 size_t page_size_words = os::vm_page_size() / BytesPerWord;
779 size_t aligned_expand_vs_by_words = align_size_up(chunk_word_size,
780 page_size_words);
781 expand_by(aligned_expand_vs_by_words, false);
782 new_chunk = get_chunk_vs(chunk_word_size);
783 }
784 return new_chunk;
785 }
787 bool VirtualSpaceNode::initialize() {
789 if (!_rs.is_reserved()) {
790 return false;
791 }
793 // An allocation out of this Virtualspace that is larger
794 // than an initial commit size can waste that initial committed
795 // space.
796 size_t committed_byte_size = 0;
797 bool result = virtual_space()->initialize(_rs, committed_byte_size);
798 if (result) {
799 set_top((MetaWord*)virtual_space()->low());
800 set_reserved(MemRegion((HeapWord*)_rs.base(),
801 (HeapWord*)(_rs.base() + _rs.size())));
803 assert(reserved()->start() == (HeapWord*) _rs.base(),
804 err_msg("Reserved start was not set properly " PTR_FORMAT
805 " != " PTR_FORMAT, reserved()->start(), _rs.base()));
806 assert(reserved()->word_size() == _rs.size() / BytesPerWord,
807 err_msg("Reserved size was not set properly " SIZE_FORMAT
808 " != " SIZE_FORMAT, reserved()->word_size(),
809 _rs.size() / BytesPerWord));
810 }
812 return result;
813 }
815 void VirtualSpaceNode::print_on(outputStream* st) const {
816 size_t used = used_words_in_vs();
817 size_t capacity = capacity_words_in_vs();
818 VirtualSpace* vs = virtual_space();
819 st->print_cr(" space @ " PTR_FORMAT " " SIZE_FORMAT "K, %3d%% used "
820 "[" PTR_FORMAT ", " PTR_FORMAT ", "
821 PTR_FORMAT ", " PTR_FORMAT ")",
822 vs, capacity / K,
823 capacity == 0 ? 0 : used * 100 / capacity,
824 bottom(), top(), end(),
825 vs->high_boundary());
826 }
828 #ifdef ASSERT
829 void VirtualSpaceNode::mangle() {
830 size_t word_size = capacity_words_in_vs();
831 Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1);
832 }
833 #endif // ASSERT
835 // VirtualSpaceList methods
836 // Space allocated from the VirtualSpace
838 VirtualSpaceList::~VirtualSpaceList() {
839 VirtualSpaceListIterator iter(virtual_space_list());
840 while (iter.repeat()) {
841 VirtualSpaceNode* vsl = iter.get_next();
842 delete vsl;
843 }
844 }
846 size_t VirtualSpaceList::used_words_sum() {
847 size_t allocated_by_vs = 0;
848 VirtualSpaceListIterator iter(virtual_space_list());
849 while (iter.repeat()) {
850 VirtualSpaceNode* vsl = iter.get_next();
851 // Sum used region [bottom, top) in each virtualspace
852 allocated_by_vs += vsl->used_words_in_vs();
853 }
854 assert(allocated_by_vs >= chunk_manager()->free_chunks_total(),
855 err_msg("Total in free chunks " SIZE_FORMAT
856 " greater than total from virtual_spaces " SIZE_FORMAT,
857 allocated_by_vs, chunk_manager()->free_chunks_total()));
858 size_t used =
859 allocated_by_vs - chunk_manager()->free_chunks_total();
860 return used;
861 }
863 // Space available in all MetadataVirtualspaces allocated
864 // for metadata. This is the upper limit on the capacity
865 // of chunks allocated out of all the MetadataVirtualspaces.
866 size_t VirtualSpaceList::capacity_words_sum() {
867 size_t capacity = 0;
868 VirtualSpaceListIterator iter(virtual_space_list());
869 while (iter.repeat()) {
870 VirtualSpaceNode* vsl = iter.get_next();
871 capacity += vsl->capacity_words_in_vs();
872 }
873 return capacity;
874 }
876 VirtualSpaceList::VirtualSpaceList(size_t word_size ) :
877 _is_class(false),
878 _virtual_space_list(NULL),
879 _current_virtual_space(NULL),
880 _virtual_space_total(0),
881 _virtual_space_count(0) {
882 MutexLockerEx cl(SpaceManager::expand_lock(),
883 Mutex::_no_safepoint_check_flag);
884 bool initialization_succeeded = grow_vs(word_size);
886 _chunk_manager.free_chunks(SpecializedIndex)->set_size(SpecializedChunk);
887 _chunk_manager.free_chunks(SmallIndex)->set_size(SmallChunk);
888 _chunk_manager.free_chunks(MediumIndex)->set_size(MediumChunk);
889 assert(initialization_succeeded,
890 " VirtualSpaceList initialization should not fail");
891 }
893 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) :
894 _is_class(true),
895 _virtual_space_list(NULL),
896 _current_virtual_space(NULL),
897 _virtual_space_total(0),
898 _virtual_space_count(0) {
899 MutexLockerEx cl(SpaceManager::expand_lock(),
900 Mutex::_no_safepoint_check_flag);
901 VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs);
902 bool succeeded = class_entry->initialize();
903 _chunk_manager.free_chunks(SpecializedIndex)->set_size(SpecializedChunk);
904 _chunk_manager.free_chunks(SmallIndex)->set_size(ClassSmallChunk);
905 _chunk_manager.free_chunks(MediumIndex)->set_size(ClassMediumChunk);
906 assert(succeeded, " VirtualSpaceList initialization should not fail");
907 link_vs(class_entry, rs.size()/BytesPerWord);
908 }
910 // Allocate another meta virtual space and add it to the list.
911 bool VirtualSpaceList::grow_vs(size_t vs_word_size) {
912 assert_lock_strong(SpaceManager::expand_lock());
913 if (vs_word_size == 0) {
914 return false;
915 }
916 // Reserve the space
917 size_t vs_byte_size = vs_word_size * BytesPerWord;
918 assert(vs_byte_size % os::vm_page_size() == 0, "Not aligned");
920 // Allocate the meta virtual space and initialize it.
921 VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size);
922 if (!new_entry->initialize()) {
923 delete new_entry;
924 return false;
925 } else {
926 // ensure lock-free iteration sees fully initialized node
927 OrderAccess::storestore();
928 link_vs(new_entry, vs_word_size);
929 return true;
930 }
931 }
933 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry, size_t vs_word_size) {
934 if (virtual_space_list() == NULL) {
935 set_virtual_space_list(new_entry);
936 } else {
937 current_virtual_space()->set_next(new_entry);
938 }
939 set_current_virtual_space(new_entry);
940 inc_virtual_space_total(vs_word_size);
941 inc_virtual_space_count();
942 #ifdef ASSERT
943 new_entry->mangle();
944 #endif
945 if (TraceMetavirtualspaceAllocation && Verbose) {
946 VirtualSpaceNode* vsl = current_virtual_space();
947 vsl->print_on(tty);
948 }
949 }
951 Metachunk* VirtualSpaceList::get_new_chunk(size_t word_size,
952 size_t grow_chunks_by_words,
953 size_t medium_chunk_bunch) {
955 // Get a chunk from the chunk freelist
956 Metachunk* next = chunk_manager()->chunk_freelist_allocate(grow_chunks_by_words);
958 // Allocate a chunk out of the current virtual space.
959 if (next == NULL) {
960 next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
961 }
963 if (next == NULL) {
964 // Not enough room in current virtual space. Try to commit
965 // more space.
966 size_t expand_vs_by_words = MAX2(medium_chunk_bunch,
967 grow_chunks_by_words);
968 size_t page_size_words = os::vm_page_size() / BytesPerWord;
969 size_t aligned_expand_vs_by_words = align_size_up(expand_vs_by_words,
970 page_size_words);
971 bool vs_expanded =
972 current_virtual_space()->expand_by(aligned_expand_vs_by_words, false);
973 if (!vs_expanded) {
974 // Should the capacity of the metaspaces be expanded for
975 // this allocation? If it's the virtual space for classes and is
976 // being used for CompressedHeaders, don't allocate a new virtualspace.
977 if (can_grow() && MetaspaceGC::should_expand(this, word_size)) {
978 // Get another virtual space.
979 size_t grow_vs_words =
980 MAX2((size_t)VirtualSpaceSize, aligned_expand_vs_by_words);
981 if (grow_vs(grow_vs_words)) {
982 // Got it. It's on the list now. Get a chunk from it.
983 next = current_virtual_space()->get_chunk_vs_with_expand(grow_chunks_by_words);
984 }
985 } else {
986 // Allocation will fail and induce a GC
987 if (TraceMetadataChunkAllocation && Verbose) {
988 gclog_or_tty->print_cr("VirtualSpaceList::get_new_chunk():"
989 " Fail instead of expand the metaspace");
990 }
991 }
992 } else {
993 // The virtual space expanded, get a new chunk
994 next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
995 assert(next != NULL, "Just expanded, should succeed");
996 }
997 }
999 assert(next == NULL || (next->next() == NULL && next->prev() == NULL),
1000 "New chunk is still on some list");
1001 return next;
1002 }
1004 Metachunk* VirtualSpaceList::get_initialization_chunk(size_t chunk_word_size,
1005 size_t chunk_bunch) {
1006 // Get a chunk from the chunk freelist
1007 Metachunk* new_chunk = get_new_chunk(chunk_word_size,
1008 chunk_word_size,
1009 chunk_bunch);
1010 return new_chunk;
1011 }
1013 void VirtualSpaceList::print_on(outputStream* st) const {
1014 if (TraceMetadataChunkAllocation && Verbose) {
1015 VirtualSpaceListIterator iter(virtual_space_list());
1016 while (iter.repeat()) {
1017 VirtualSpaceNode* node = iter.get_next();
1018 node->print_on(st);
1019 }
1020 }
1021 }
1023 bool VirtualSpaceList::contains(const void *ptr) {
1024 VirtualSpaceNode* list = virtual_space_list();
1025 VirtualSpaceListIterator iter(list);
1026 while (iter.repeat()) {
1027 VirtualSpaceNode* node = iter.get_next();
1028 if (node->reserved()->contains(ptr)) {
1029 return true;
1030 }
1031 }
1032 return false;
1033 }
1036 // MetaspaceGC methods
1038 // VM_CollectForMetadataAllocation is the vm operation used to GC.
1039 // Within the VM operation after the GC the attempt to allocate the metadata
1040 // should succeed. If the GC did not free enough space for the metaspace
1041 // allocation, the HWM is increased so that another virtualspace will be
1042 // allocated for the metadata. With perm gen the increase in the perm
1043 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The
1044 // metaspace policy uses those as the small and large steps for the HWM.
1045 //
1046 // After the GC the compute_new_size() for MetaspaceGC is called to
1047 // resize the capacity of the metaspaces. The current implementation
1048 // is based on the flags MinMetaspaceFreeRatio and MaxHeapFreeRatio used
1049 // to resize the Java heap by some GC's. New flags can be implemented
1050 // if really needed. MinHeapFreeRatio is used to calculate how much
1051 // free space is desirable in the metaspace capacity to decide how much
1052 // to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much
1053 // free space is desirable in the metaspace capacity before decreasing
1054 // the HWM.
1056 // Calculate the amount to increase the high water mark (HWM).
1057 // Increase by a minimum amount (MinMetaspaceExpansion) so that
1058 // another expansion is not requested too soon. If that is not
1059 // enough to satisfy the allocation (i.e. big enough for a word_size
1060 // allocation), increase by MaxMetaspaceExpansion. If that is still
1061 // not enough, expand by the size of the allocation (word_size) plus
1062 // some.
1063 size_t MetaspaceGC::delta_capacity_until_GC(size_t word_size) {
1064 size_t before_inc = MetaspaceGC::capacity_until_GC();
1065 size_t min_delta_words = MinMetaspaceExpansion / BytesPerWord;
1066 size_t max_delta_words = MaxMetaspaceExpansion / BytesPerWord;
1067 size_t page_size_words = os::vm_page_size() / BytesPerWord;
1068 size_t size_delta_words = align_size_up(word_size, page_size_words);
1069 size_t delta_words = MAX2(size_delta_words, min_delta_words);
1070 if (delta_words > min_delta_words) {
1071 // Don't want to hit the high water mark on the next
1072 // allocation so make the delta greater than just enough
1073 // for this allocation.
1074 delta_words = MAX2(delta_words, max_delta_words);
1075 if (delta_words > max_delta_words) {
1076 // This allocation is large but the next ones are probably not
1077 // so increase by the minimum.
1078 delta_words = delta_words + min_delta_words;
1079 }
1080 }
1081 return delta_words;
1082 }
1084 bool MetaspaceGC::should_expand(VirtualSpaceList* vsl, size_t word_size) {
1085 // If the user wants a limit, impose one.
1086 if (!FLAG_IS_DEFAULT(MaxMetaspaceSize) &&
1087 MetaspaceAux::reserved_in_bytes() >= MaxMetaspaceSize) {
1088 return false;
1089 }
1091 // Class virtual space should always be expanded. Call GC for the other
1092 // metadata virtual space.
1093 if (vsl == Metaspace::class_space_list()) return true;
1095 // If this is part of an allocation after a GC, expand
1096 // unconditionally.
1097 if(MetaspaceGC::expand_after_GC()) {
1098 return true;
1099 }
1101 size_t metaspace_size_words = MetaspaceSize / BytesPerWord;
1103 // If the capacity is below the minimum capacity, allow the
1104 // expansion. Also set the high-water-mark (capacity_until_GC)
1105 // to that minimum capacity so that a GC will not be induced
1106 // until that minimum capacity is exceeded.
1107 if (vsl->capacity_words_sum() < metaspace_size_words ||
1108 capacity_until_GC() == 0) {
1109 set_capacity_until_GC(metaspace_size_words);
1110 return true;
1111 } else {
1112 if (vsl->capacity_words_sum() < capacity_until_GC()) {
1113 return true;
1114 } else {
1115 if (TraceMetadataChunkAllocation && Verbose) {
1116 gclog_or_tty->print_cr(" allocation request size " SIZE_FORMAT
1117 " capacity_until_GC " SIZE_FORMAT
1118 " capacity_words_sum " SIZE_FORMAT
1119 " used_words_sum " SIZE_FORMAT
1120 " free chunks " SIZE_FORMAT
1121 " free chunks count %d",
1122 word_size,
1123 capacity_until_GC(),
1124 vsl->capacity_words_sum(),
1125 vsl->used_words_sum(),
1126 vsl->chunk_manager()->free_chunks_total(),
1127 vsl->chunk_manager()->free_chunks_count());
1128 }
1129 return false;
1130 }
1131 }
1132 }
1134 // Variables are in bytes
1136 void MetaspaceGC::compute_new_size() {
1137 assert(_shrink_factor <= 100, "invalid shrink factor");
1138 uint current_shrink_factor = _shrink_factor;
1139 _shrink_factor = 0;
1141 VirtualSpaceList *vsl = Metaspace::space_list();
1143 size_t capacity_after_gc = vsl->capacity_bytes_sum();
1144 // Check to see if these two can be calculated without walking the CLDG
1145 size_t used_after_gc = vsl->used_bytes_sum();
1146 size_t capacity_until_GC = vsl->capacity_bytes_sum();
1147 size_t free_after_gc = capacity_until_GC - used_after_gc;
1149 const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0;
1150 const double maximum_used_percentage = 1.0 - minimum_free_percentage;
1152 const double min_tmp = used_after_gc / maximum_used_percentage;
1153 size_t minimum_desired_capacity =
1154 (size_t)MIN2(min_tmp, double(max_uintx));
1155 // Don't shrink less than the initial generation size
1156 minimum_desired_capacity = MAX2(minimum_desired_capacity,
1157 MetaspaceSize);
1159 if (PrintGCDetails && Verbose) {
1160 const double free_percentage = ((double)free_after_gc) / capacity_until_GC;
1161 gclog_or_tty->print_cr("\nMetaspaceGC::compute_new_size: ");
1162 gclog_or_tty->print_cr(" "
1163 " minimum_free_percentage: %6.2f"
1164 " maximum_used_percentage: %6.2f",
1165 minimum_free_percentage,
1166 maximum_used_percentage);
1167 double d_free_after_gc = free_after_gc / (double) K;
1168 gclog_or_tty->print_cr(" "
1169 " free_after_gc : %6.1fK"
1170 " used_after_gc : %6.1fK"
1171 " capacity_after_gc : %6.1fK"
1172 " metaspace HWM : %6.1fK",
1173 free_after_gc / (double) K,
1174 used_after_gc / (double) K,
1175 capacity_after_gc / (double) K,
1176 capacity_until_GC / (double) K);
1177 gclog_or_tty->print_cr(" "
1178 " free_percentage: %6.2f",
1179 free_percentage);
1180 }
1183 if (capacity_until_GC < minimum_desired_capacity) {
1184 // If we have less capacity below the metaspace HWM, then
1185 // increment the HWM.
1186 size_t expand_bytes = minimum_desired_capacity - capacity_until_GC;
1187 // Don't expand unless it's significant
1188 if (expand_bytes >= MinMetaspaceExpansion) {
1189 size_t expand_words = expand_bytes / BytesPerWord;
1190 MetaspaceGC::inc_capacity_until_GC(expand_words);
1191 }
1192 if (PrintGCDetails && Verbose) {
1193 size_t new_capacity_until_GC = MetaspaceGC::capacity_until_GC_in_bytes();
1194 gclog_or_tty->print_cr(" expanding:"
1195 " minimum_desired_capacity: %6.1fK"
1196 " expand_words: %6.1fK"
1197 " MinMetaspaceExpansion: %6.1fK"
1198 " new metaspace HWM: %6.1fK",
1199 minimum_desired_capacity / (double) K,
1200 expand_bytes / (double) K,
1201 MinMetaspaceExpansion / (double) K,
1202 new_capacity_until_GC / (double) K);
1203 }
1204 return;
1205 }
1207 // No expansion, now see if we want to shrink
1208 size_t shrink_words = 0;
1209 // We would never want to shrink more than this
1210 size_t max_shrink_words = capacity_until_GC - minimum_desired_capacity;
1211 assert(max_shrink_words >= 0, err_msg("max_shrink_words " SIZE_FORMAT,
1212 max_shrink_words));
1214 // Should shrinking be considered?
1215 if (MaxMetaspaceFreeRatio < 100) {
1216 const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0;
1217 const double minimum_used_percentage = 1.0 - maximum_free_percentage;
1218 const double max_tmp = used_after_gc / minimum_used_percentage;
1219 size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx));
1220 maximum_desired_capacity = MAX2(maximum_desired_capacity,
1221 MetaspaceSize);
1222 if (PrintGC && Verbose) {
1223 gclog_or_tty->print_cr(" "
1224 " maximum_free_percentage: %6.2f"
1225 " minimum_used_percentage: %6.2f",
1226 maximum_free_percentage,
1227 minimum_used_percentage);
1228 gclog_or_tty->print_cr(" "
1229 " capacity_until_GC: %6.1fK"
1230 " minimum_desired_capacity: %6.1fK"
1231 " maximum_desired_capacity: %6.1fK",
1232 capacity_until_GC / (double) K,
1233 minimum_desired_capacity / (double) K,
1234 maximum_desired_capacity / (double) K);
1235 }
1237 assert(minimum_desired_capacity <= maximum_desired_capacity,
1238 "sanity check");
1240 if (capacity_until_GC > maximum_desired_capacity) {
1241 // Capacity too large, compute shrinking size
1242 shrink_words = capacity_until_GC - maximum_desired_capacity;
1243 // We don't want shrink all the way back to initSize if people call
1244 // System.gc(), because some programs do that between "phases" and then
1245 // we'd just have to grow the heap up again for the next phase. So we
1246 // damp the shrinking: 0% on the first call, 10% on the second call, 40%
1247 // on the third call, and 100% by the fourth call. But if we recompute
1248 // size without shrinking, it goes back to 0%.
1249 shrink_words = shrink_words / 100 * current_shrink_factor;
1250 assert(shrink_words <= max_shrink_words,
1251 err_msg("invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT,
1252 shrink_words, max_shrink_words));
1253 if (current_shrink_factor == 0) {
1254 _shrink_factor = 10;
1255 } else {
1256 _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100);
1257 }
1258 if (PrintGCDetails && Verbose) {
1259 gclog_or_tty->print_cr(" "
1260 " shrinking:"
1261 " initSize: %.1fK"
1262 " maximum_desired_capacity: %.1fK",
1263 MetaspaceSize / (double) K,
1264 maximum_desired_capacity / (double) K);
1265 gclog_or_tty->print_cr(" "
1266 " shrink_words: %.1fK"
1267 " current_shrink_factor: %d"
1268 " new shrink factor: %d"
1269 " MinMetaspaceExpansion: %.1fK",
1270 shrink_words / (double) K,
1271 current_shrink_factor,
1272 _shrink_factor,
1273 MinMetaspaceExpansion / (double) K);
1274 }
1275 }
1276 }
1279 // Don't shrink unless it's significant
1280 if (shrink_words >= MinMetaspaceExpansion) {
1281 VirtualSpaceNode* csp = vsl->current_virtual_space();
1282 size_t available_to_shrink = csp->capacity_words_in_vs() -
1283 csp->used_words_in_vs();
1284 shrink_words = MIN2(shrink_words, available_to_shrink);
1285 csp->shrink_by(shrink_words);
1286 MetaspaceGC::dec_capacity_until_GC(shrink_words);
1287 if (PrintGCDetails && Verbose) {
1288 size_t new_capacity_until_GC = MetaspaceGC::capacity_until_GC_in_bytes();
1289 gclog_or_tty->print_cr(" metaspace HWM: %.1fK", new_capacity_until_GC / (double) K);
1290 }
1291 }
1292 assert(used_after_gc <= vsl->capacity_bytes_sum(),
1293 "sanity check");
1295 }
1297 // Metadebug methods
1299 void Metadebug::deallocate_chunk_a_lot(SpaceManager* sm,
1300 size_t chunk_word_size){
1301 #ifdef ASSERT
1302 VirtualSpaceList* vsl = sm->vs_list();
1303 if (MetaDataDeallocateALot &&
1304 Metadebug::deallocate_chunk_a_lot_count() % MetaDataDeallocateALotInterval == 0 ) {
1305 Metadebug::reset_deallocate_chunk_a_lot_count();
1306 for (uint i = 0; i < metadata_deallocate_a_lock_chunk; i++) {
1307 Metachunk* dummy_chunk = vsl->current_virtual_space()->take_from_committed(chunk_word_size);
1308 if (dummy_chunk == NULL) {
1309 break;
1310 }
1311 vsl->chunk_manager()->chunk_freelist_deallocate(dummy_chunk);
1313 if (TraceMetadataChunkAllocation && Verbose) {
1314 gclog_or_tty->print("Metadebug::deallocate_chunk_a_lot: %d) ",
1315 sm->sum_count_in_chunks_in_use());
1316 dummy_chunk->print_on(gclog_or_tty);
1317 gclog_or_tty->print_cr(" Free chunks total %d count %d",
1318 vsl->chunk_manager()->free_chunks_total(),
1319 vsl->chunk_manager()->free_chunks_count());
1320 }
1321 }
1322 } else {
1323 Metadebug::inc_deallocate_chunk_a_lot_count();
1324 }
1325 #endif
1326 }
1328 void Metadebug::deallocate_block_a_lot(SpaceManager* sm,
1329 size_t raw_word_size){
1330 #ifdef ASSERT
1331 if (MetaDataDeallocateALot &&
1332 Metadebug::deallocate_block_a_lot_count() % MetaDataDeallocateALotInterval == 0 ) {
1333 Metadebug::set_deallocate_block_a_lot_count(0);
1334 for (uint i = 0; i < metadata_deallocate_a_lot_block; i++) {
1335 MetaWord* dummy_block = sm->allocate_work(raw_word_size);
1336 if (dummy_block == 0) {
1337 break;
1338 }
1339 sm->deallocate(dummy_block, raw_word_size);
1340 }
1341 } else {
1342 Metadebug::inc_deallocate_block_a_lot_count();
1343 }
1344 #endif
1345 }
1347 void Metadebug::init_allocation_fail_alot_count() {
1348 if (MetadataAllocationFailALot) {
1349 _allocation_fail_alot_count =
1350 1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0));
1351 }
1352 }
1354 #ifdef ASSERT
1355 bool Metadebug::test_metadata_failure() {
1356 if (MetadataAllocationFailALot &&
1357 Threads::is_vm_complete()) {
1358 if (_allocation_fail_alot_count > 0) {
1359 _allocation_fail_alot_count--;
1360 } else {
1361 if (TraceMetadataChunkAllocation && Verbose) {
1362 gclog_or_tty->print_cr("Metadata allocation failing for "
1363 "MetadataAllocationFailALot");
1364 }
1365 init_allocation_fail_alot_count();
1366 return true;
1367 }
1368 }
1369 return false;
1370 }
1371 #endif
1373 // ChunkManager methods
1375 // Verification of _free_chunks_total and _free_chunks_count does not
1376 // work with the CMS collector because its use of additional locks
1377 // complicate the mutex deadlock detection but it can still be useful
1378 // for detecting errors in the chunk accounting with other collectors.
1380 size_t ChunkManager::free_chunks_total() {
1381 #ifdef ASSERT
1382 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
1383 MutexLockerEx cl(SpaceManager::expand_lock(),
1384 Mutex::_no_safepoint_check_flag);
1385 slow_locked_verify_free_chunks_total();
1386 }
1387 #endif
1388 return _free_chunks_total;
1389 }
1391 size_t ChunkManager::free_chunks_total_in_bytes() {
1392 return free_chunks_total() * BytesPerWord;
1393 }
1395 size_t ChunkManager::free_chunks_count() {
1396 #ifdef ASSERT
1397 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
1398 MutexLockerEx cl(SpaceManager::expand_lock(),
1399 Mutex::_no_safepoint_check_flag);
1400 // This lock is only needed in debug because the verification
1401 // of the _free_chunks_totals walks the list of free chunks
1402 slow_locked_verify_free_chunks_count();
1403 }
1404 #endif
1405 return _free_chunks_count;
1406 }
1408 void ChunkManager::locked_verify_free_chunks_total() {
1409 assert_lock_strong(SpaceManager::expand_lock());
1410 assert(sum_free_chunks() == _free_chunks_total,
1411 err_msg("_free_chunks_total " SIZE_FORMAT " is not the"
1412 " same as sum " SIZE_FORMAT, _free_chunks_total,
1413 sum_free_chunks()));
1414 }
1416 void ChunkManager::verify_free_chunks_total() {
1417 MutexLockerEx cl(SpaceManager::expand_lock(),
1418 Mutex::_no_safepoint_check_flag);
1419 locked_verify_free_chunks_total();
1420 }
1422 void ChunkManager::locked_verify_free_chunks_count() {
1423 assert_lock_strong(SpaceManager::expand_lock());
1424 assert(sum_free_chunks_count() == _free_chunks_count,
1425 err_msg("_free_chunks_count " SIZE_FORMAT " is not the"
1426 " same as sum " SIZE_FORMAT, _free_chunks_count,
1427 sum_free_chunks_count()));
1428 }
1430 void ChunkManager::verify_free_chunks_count() {
1431 #ifdef ASSERT
1432 MutexLockerEx cl(SpaceManager::expand_lock(),
1433 Mutex::_no_safepoint_check_flag);
1434 locked_verify_free_chunks_count();
1435 #endif
1436 }
1438 void ChunkManager::verify() {
1439 MutexLockerEx cl(SpaceManager::expand_lock(),
1440 Mutex::_no_safepoint_check_flag);
1441 locked_verify();
1442 }
1444 void ChunkManager::locked_verify() {
1445 locked_verify_free_chunks_count();
1446 locked_verify_free_chunks_total();
1447 }
1449 void ChunkManager::locked_print_free_chunks(outputStream* st) {
1450 assert_lock_strong(SpaceManager::expand_lock());
1451 st->print_cr("Free chunk total " SIZE_FORMAT " count " SIZE_FORMAT,
1452 _free_chunks_total, _free_chunks_count);
1453 }
1455 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) {
1456 assert_lock_strong(SpaceManager::expand_lock());
1457 st->print_cr("Sum free chunk total " SIZE_FORMAT " count " SIZE_FORMAT,
1458 sum_free_chunks(), sum_free_chunks_count());
1459 }
1460 ChunkList* ChunkManager::free_chunks(ChunkIndex index) {
1461 return &_free_chunks[index];
1462 }
1464 // These methods that sum the free chunk lists are used in printing
1465 // methods that are used in product builds.
1466 size_t ChunkManager::sum_free_chunks() {
1467 assert_lock_strong(SpaceManager::expand_lock());
1468 size_t result = 0;
1469 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1470 ChunkList* list = free_chunks(i);
1472 if (list == NULL) {
1473 continue;
1474 }
1476 result = result + list->count() * list->size();
1477 }
1478 result = result + humongous_dictionary()->total_size();
1479 return result;
1480 }
1482 size_t ChunkManager::sum_free_chunks_count() {
1483 assert_lock_strong(SpaceManager::expand_lock());
1484 size_t count = 0;
1485 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1486 ChunkList* list = free_chunks(i);
1487 if (list == NULL) {
1488 continue;
1489 }
1490 count = count + list->count();
1491 }
1492 count = count + humongous_dictionary()->total_free_blocks();
1493 return count;
1494 }
1496 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) {
1497 ChunkIndex index = list_index(word_size);
1498 assert(index < HumongousIndex, "No humongous list");
1499 return free_chunks(index);
1500 }
1502 void ChunkManager::free_chunks_put(Metachunk* chunk) {
1503 assert_lock_strong(SpaceManager::expand_lock());
1504 ChunkList* free_list = find_free_chunks_list(chunk->word_size());
1505 chunk->set_next(free_list->head());
1506 free_list->set_head(chunk);
1507 // chunk is being returned to the chunk free list
1508 inc_free_chunks_total(chunk->capacity_word_size());
1509 slow_locked_verify();
1510 }
1512 void ChunkManager::chunk_freelist_deallocate(Metachunk* chunk) {
1513 // The deallocation of a chunk originates in the freelist
1514 // manangement code for a Metaspace and does not hold the
1515 // lock.
1516 assert(chunk != NULL, "Deallocating NULL");
1517 assert_lock_strong(SpaceManager::expand_lock());
1518 slow_locked_verify();
1519 if (TraceMetadataChunkAllocation) {
1520 tty->print_cr("ChunkManager::chunk_freelist_deallocate: chunk "
1521 PTR_FORMAT " size " SIZE_FORMAT,
1522 chunk, chunk->word_size());
1523 }
1524 free_chunks_put(chunk);
1525 }
1527 Metachunk* ChunkManager::free_chunks_get(size_t word_size) {
1528 assert_lock_strong(SpaceManager::expand_lock());
1530 slow_locked_verify();
1532 Metachunk* chunk = NULL;
1533 if (list_index(word_size) != HumongousIndex) {
1534 ChunkList* free_list = find_free_chunks_list(word_size);
1535 assert(free_list != NULL, "Sanity check");
1537 chunk = free_list->head();
1538 debug_only(Metachunk* debug_head = chunk;)
1540 if (chunk == NULL) {
1541 return NULL;
1542 }
1544 // Remove the chunk as the head of the list.
1545 free_list->remove_chunk(chunk);
1547 // Chunk is being removed from the chunks free list.
1548 dec_free_chunks_total(chunk->capacity_word_size());
1550 if (TraceMetadataChunkAllocation && Verbose) {
1551 tty->print_cr("ChunkManager::free_chunks_get: free_list "
1552 PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT,
1553 free_list, chunk, chunk->word_size());
1554 }
1555 } else {
1556 chunk = humongous_dictionary()->get_chunk(
1557 word_size,
1558 FreeBlockDictionary<Metachunk>::atLeast);
1560 if (chunk != NULL) {
1561 if (TraceMetadataHumongousAllocation) {
1562 size_t waste = chunk->word_size() - word_size;
1563 tty->print_cr("Free list allocate humongous chunk size " SIZE_FORMAT
1564 " for requested size " SIZE_FORMAT
1565 " waste " SIZE_FORMAT,
1566 chunk->word_size(), word_size, waste);
1567 }
1568 // Chunk is being removed from the chunks free list.
1569 dec_free_chunks_total(chunk->capacity_word_size());
1570 #ifdef ASSERT
1571 chunk->set_is_free(false);
1572 #endif
1573 } else {
1574 return NULL;
1575 }
1576 }
1578 // Remove it from the links to this freelist
1579 chunk->set_next(NULL);
1580 chunk->set_prev(NULL);
1581 slow_locked_verify();
1582 return chunk;
1583 }
1585 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) {
1586 assert_lock_strong(SpaceManager::expand_lock());
1587 slow_locked_verify();
1589 // Take from the beginning of the list
1590 Metachunk* chunk = free_chunks_get(word_size);
1591 if (chunk == NULL) {
1592 return NULL;
1593 }
1595 assert((word_size <= chunk->word_size()) ||
1596 list_index(chunk->word_size() == HumongousIndex),
1597 "Non-humongous variable sized chunk");
1598 if (TraceMetadataChunkAllocation) {
1599 size_t list_count;
1600 if (list_index(word_size) < HumongousIndex) {
1601 ChunkList* list = find_free_chunks_list(word_size);
1602 list_count = list->count();
1603 } else {
1604 list_count = humongous_dictionary()->total_count();
1605 }
1606 tty->print("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk "
1607 PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ",
1608 this, chunk, chunk->word_size(), list_count);
1609 locked_print_free_chunks(tty);
1610 }
1612 return chunk;
1613 }
1615 void ChunkManager::print_on(outputStream* out) {
1616 if (PrintFLSStatistics != 0) {
1617 humongous_dictionary()->report_statistics();
1618 }
1619 }
1621 // SpaceManager methods
1623 void SpaceManager::get_initial_chunk_sizes(Metaspace::MetaspaceType type,
1624 size_t* chunk_word_size,
1625 size_t* class_chunk_word_size) {
1626 switch (type) {
1627 case Metaspace::BootMetaspaceType:
1628 *chunk_word_size = Metaspace::first_chunk_word_size();
1629 *class_chunk_word_size = Metaspace::first_class_chunk_word_size();
1630 break;
1631 case Metaspace::ROMetaspaceType:
1632 *chunk_word_size = SharedReadOnlySize / wordSize;
1633 *class_chunk_word_size = ClassSpecializedChunk;
1634 break;
1635 case Metaspace::ReadWriteMetaspaceType:
1636 *chunk_word_size = SharedReadWriteSize / wordSize;
1637 *class_chunk_word_size = ClassSpecializedChunk;
1638 break;
1639 case Metaspace::AnonymousMetaspaceType:
1640 case Metaspace::ReflectionMetaspaceType:
1641 *chunk_word_size = SpecializedChunk;
1642 *class_chunk_word_size = ClassSpecializedChunk;
1643 break;
1644 default:
1645 *chunk_word_size = SmallChunk;
1646 *class_chunk_word_size = ClassSmallChunk;
1647 break;
1648 }
1649 assert(*chunk_word_size != 0 && *class_chunk_word_size != 0,
1650 err_msg("Initial chunks sizes bad: data " SIZE_FORMAT
1651 " class " SIZE_FORMAT,
1652 *chunk_word_size, *class_chunk_word_size));
1653 }
1655 size_t SpaceManager::sum_free_in_chunks_in_use() const {
1656 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1657 size_t free = 0;
1658 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1659 Metachunk* chunk = chunks_in_use(i);
1660 while (chunk != NULL) {
1661 free += chunk->free_word_size();
1662 chunk = chunk->next();
1663 }
1664 }
1665 return free;
1666 }
1668 size_t SpaceManager::sum_waste_in_chunks_in_use() const {
1669 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1670 size_t result = 0;
1671 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1672 result += sum_waste_in_chunks_in_use(i);
1673 }
1675 return result;
1676 }
1678 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const {
1679 size_t result = 0;
1680 Metachunk* chunk = chunks_in_use(index);
1681 // Count the free space in all the chunk but not the
1682 // current chunk from which allocations are still being done.
1683 if (chunk != NULL) {
1684 Metachunk* prev = chunk;
1685 while (chunk != NULL && chunk != current_chunk()) {
1686 result += chunk->free_word_size();
1687 prev = chunk;
1688 chunk = chunk->next();
1689 }
1690 }
1691 return result;
1692 }
1694 size_t SpaceManager::sum_capacity_in_chunks_in_use() const {
1695 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1696 size_t sum = 0;
1697 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1698 Metachunk* chunk = chunks_in_use(i);
1699 while (chunk != NULL) {
1700 // Just changed this sum += chunk->capacity_word_size();
1701 // sum += chunk->word_size() - Metachunk::overhead();
1702 sum += chunk->capacity_word_size();
1703 chunk = chunk->next();
1704 }
1705 }
1706 return sum;
1707 }
1709 size_t SpaceManager::sum_count_in_chunks_in_use() {
1710 size_t count = 0;
1711 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1712 count = count + sum_count_in_chunks_in_use(i);
1713 }
1715 return count;
1716 }
1718 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) {
1719 size_t count = 0;
1720 Metachunk* chunk = chunks_in_use(i);
1721 while (chunk != NULL) {
1722 count++;
1723 chunk = chunk->next();
1724 }
1725 return count;
1726 }
1729 size_t SpaceManager::sum_used_in_chunks_in_use() const {
1730 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1731 size_t used = 0;
1732 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1733 Metachunk* chunk = chunks_in_use(i);
1734 while (chunk != NULL) {
1735 used += chunk->used_word_size();
1736 chunk = chunk->next();
1737 }
1738 }
1739 return used;
1740 }
1742 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const {
1744 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1745 Metachunk* chunk = chunks_in_use(i);
1746 st->print("SpaceManager: %s " PTR_FORMAT,
1747 chunk_size_name(i), chunk);
1748 if (chunk != NULL) {
1749 st->print_cr(" free " SIZE_FORMAT,
1750 chunk->free_word_size());
1751 } else {
1752 st->print_cr("");
1753 }
1754 }
1756 vs_list()->chunk_manager()->locked_print_free_chunks(st);
1757 vs_list()->chunk_manager()->locked_print_sum_free_chunks(st);
1758 }
1760 size_t SpaceManager::calc_chunk_size(size_t word_size) {
1762 // Decide between a small chunk and a medium chunk. Up to
1763 // _small_chunk_limit small chunks can be allocated but
1764 // once a medium chunk has been allocated, no more small
1765 // chunks will be allocated.
1766 size_t chunk_word_size;
1767 if (chunks_in_use(MediumIndex) == NULL &&
1768 (!has_small_chunk_limit() ||
1769 sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit)) {
1770 chunk_word_size = (size_t) small_chunk_size();
1771 if (word_size + Metachunk::overhead() > small_chunk_size()) {
1772 chunk_word_size = medium_chunk_size();
1773 }
1774 } else {
1775 chunk_word_size = medium_chunk_size();
1776 }
1778 // Might still need a humongous chunk. Enforce an
1779 // eight word granularity to facilitate reuse (some
1780 // wastage but better chance of reuse).
1781 size_t if_humongous_sized_chunk =
1782 align_size_up(word_size + Metachunk::overhead(),
1783 HumongousChunkGranularity);
1784 chunk_word_size =
1785 MAX2((size_t) chunk_word_size, if_humongous_sized_chunk);
1787 assert(!SpaceManager::is_humongous(word_size) ||
1788 chunk_word_size == if_humongous_sized_chunk,
1789 err_msg("Size calculation is wrong, word_size " SIZE_FORMAT
1790 " chunk_word_size " SIZE_FORMAT,
1791 word_size, chunk_word_size));
1792 if (TraceMetadataHumongousAllocation &&
1793 SpaceManager::is_humongous(word_size)) {
1794 gclog_or_tty->print_cr("Metadata humongous allocation:");
1795 gclog_or_tty->print_cr(" word_size " PTR_FORMAT, word_size);
1796 gclog_or_tty->print_cr(" chunk_word_size " PTR_FORMAT,
1797 chunk_word_size);
1798 gclog_or_tty->print_cr(" chunk overhead " PTR_FORMAT,
1799 Metachunk::overhead());
1800 }
1801 return chunk_word_size;
1802 }
1804 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) {
1805 assert(vs_list()->current_virtual_space() != NULL,
1806 "Should have been set");
1807 assert(current_chunk() == NULL ||
1808 current_chunk()->allocate(word_size) == NULL,
1809 "Don't need to expand");
1810 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
1812 if (TraceMetadataChunkAllocation && Verbose) {
1813 size_t words_left = 0;
1814 size_t words_used = 0;
1815 if (current_chunk() != NULL) {
1816 words_left = current_chunk()->free_word_size();
1817 words_used = current_chunk()->used_word_size();
1818 }
1819 gclog_or_tty->print_cr("SpaceManager::grow_and_allocate for " SIZE_FORMAT
1820 " words " SIZE_FORMAT " words used " SIZE_FORMAT
1821 " words left",
1822 word_size, words_used, words_left);
1823 }
1825 // Get another chunk out of the virtual space
1826 size_t grow_chunks_by_words = calc_chunk_size(word_size);
1827 Metachunk* next = get_new_chunk(word_size, grow_chunks_by_words);
1829 // If a chunk was available, add it to the in-use chunk list
1830 // and do an allocation from it.
1831 if (next != NULL) {
1832 Metadebug::deallocate_chunk_a_lot(this, grow_chunks_by_words);
1833 // Add to this manager's list of chunks in use.
1834 add_chunk(next, false);
1835 return next->allocate(word_size);
1836 }
1837 return NULL;
1838 }
1840 void SpaceManager::print_on(outputStream* st) const {
1842 for (ChunkIndex i = ZeroIndex;
1843 i < NumberOfInUseLists ;
1844 i = next_chunk_index(i) ) {
1845 st->print_cr(" chunks_in_use " PTR_FORMAT " chunk size " PTR_FORMAT,
1846 chunks_in_use(i),
1847 chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size());
1848 }
1849 st->print_cr(" waste: Small " SIZE_FORMAT " Medium " SIZE_FORMAT
1850 " Humongous " SIZE_FORMAT,
1851 sum_waste_in_chunks_in_use(SmallIndex),
1852 sum_waste_in_chunks_in_use(MediumIndex),
1853 sum_waste_in_chunks_in_use(HumongousIndex));
1854 // block free lists
1855 if (block_freelists() != NULL) {
1856 st->print_cr("total in block free lists " SIZE_FORMAT,
1857 block_freelists()->total_size());
1858 }
1859 }
1861 SpaceManager::SpaceManager(Mutex* lock,
1862 VirtualSpaceList* vs_list) :
1863 _vs_list(vs_list),
1864 _allocation_total(0),
1865 _lock(lock)
1866 {
1867 initialize();
1868 }
1870 void SpaceManager::initialize() {
1871 Metadebug::init_allocation_fail_alot_count();
1872 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1873 _chunks_in_use[i] = NULL;
1874 }
1875 _current_chunk = NULL;
1876 if (TraceMetadataChunkAllocation && Verbose) {
1877 gclog_or_tty->print_cr("SpaceManager(): " PTR_FORMAT, this);
1878 }
1879 }
1881 void ChunkManager::return_chunks(ChunkIndex index, Metachunk* chunks) {
1882 if (chunks == NULL) {
1883 return;
1884 }
1885 ChunkList* list = free_chunks(index);
1886 assert(list->size() == chunks->word_size(), "Mismatch in chunk sizes");
1887 assert_lock_strong(SpaceManager::expand_lock());
1888 Metachunk* cur = chunks;
1890 // This return chunks one at a time. If a new
1891 // class List can be created that is a base class
1892 // of FreeList then something like FreeList::prepend()
1893 // can be used in place of this loop
1894 while (cur != NULL) {
1895 // Capture the next link before it is changed
1896 // by the call to return_chunk_at_head();
1897 Metachunk* next = cur->next();
1898 cur->set_is_free(true);
1899 list->return_chunk_at_head(cur);
1900 cur = next;
1901 }
1902 }
1904 SpaceManager::~SpaceManager() {
1905 // This call this->_lock which can't be done while holding expand_lock()
1906 const size_t in_use_before = sum_capacity_in_chunks_in_use();
1908 MutexLockerEx fcl(SpaceManager::expand_lock(),
1909 Mutex::_no_safepoint_check_flag);
1911 ChunkManager* chunk_manager = vs_list()->chunk_manager();
1913 chunk_manager->slow_locked_verify();
1915 if (TraceMetadataChunkAllocation && Verbose) {
1916 gclog_or_tty->print_cr("~SpaceManager(): " PTR_FORMAT, this);
1917 locked_print_chunks_in_use_on(gclog_or_tty);
1918 }
1920 // Mangle freed memory.
1921 NOT_PRODUCT(mangle_freed_chunks();)
1923 // Have to update before the chunks_in_use lists are emptied
1924 // below.
1925 chunk_manager->inc_free_chunks_total(in_use_before,
1926 sum_count_in_chunks_in_use());
1928 // Add all the chunks in use by this space manager
1929 // to the global list of free chunks.
1931 // Follow each list of chunks-in-use and add them to the
1932 // free lists. Each list is NULL terminated.
1934 for (ChunkIndex i = ZeroIndex; i < HumongousIndex; i = next_chunk_index(i)) {
1935 if (TraceMetadataChunkAllocation && Verbose) {
1936 gclog_or_tty->print_cr("returned %d %s chunks to freelist",
1937 sum_count_in_chunks_in_use(i),
1938 chunk_size_name(i));
1939 }
1940 Metachunk* chunks = chunks_in_use(i);
1941 chunk_manager->return_chunks(i, chunks);
1942 set_chunks_in_use(i, NULL);
1943 if (TraceMetadataChunkAllocation && Verbose) {
1944 gclog_or_tty->print_cr("updated freelist count %d %s",
1945 chunk_manager->free_chunks(i)->count(),
1946 chunk_size_name(i));
1947 }
1948 assert(i != HumongousIndex, "Humongous chunks are handled explicitly later");
1949 }
1951 // The medium chunk case may be optimized by passing the head and
1952 // tail of the medium chunk list to add_at_head(). The tail is often
1953 // the current chunk but there are probably exceptions.
1955 // Humongous chunks
1956 if (TraceMetadataChunkAllocation && Verbose) {
1957 gclog_or_tty->print_cr("returned %d %s humongous chunks to dictionary",
1958 sum_count_in_chunks_in_use(HumongousIndex),
1959 chunk_size_name(HumongousIndex));
1960 gclog_or_tty->print("Humongous chunk dictionary: ");
1961 }
1962 // Humongous chunks are never the current chunk.
1963 Metachunk* humongous_chunks = chunks_in_use(HumongousIndex);
1965 while (humongous_chunks != NULL) {
1966 #ifdef ASSERT
1967 humongous_chunks->set_is_free(true);
1968 #endif
1969 if (TraceMetadataChunkAllocation && Verbose) {
1970 gclog_or_tty->print(PTR_FORMAT " (" SIZE_FORMAT ") ",
1971 humongous_chunks,
1972 humongous_chunks->word_size());
1973 }
1974 assert(humongous_chunks->word_size() == (size_t)
1975 align_size_up(humongous_chunks->word_size(),
1976 HumongousChunkGranularity),
1977 err_msg("Humongous chunk size is wrong: word size " SIZE_FORMAT
1978 " granularity %d",
1979 humongous_chunks->word_size(), HumongousChunkGranularity));
1980 Metachunk* next_humongous_chunks = humongous_chunks->next();
1981 chunk_manager->humongous_dictionary()->return_chunk(humongous_chunks);
1982 humongous_chunks = next_humongous_chunks;
1983 }
1984 if (TraceMetadataChunkAllocation && Verbose) {
1985 gclog_or_tty->print_cr("");
1986 gclog_or_tty->print_cr("updated dictionary count %d %s",
1987 chunk_manager->humongous_dictionary()->total_count(),
1988 chunk_size_name(HumongousIndex));
1989 }
1990 set_chunks_in_use(HumongousIndex, NULL);
1991 chunk_manager->slow_locked_verify();
1992 }
1994 const char* SpaceManager::chunk_size_name(ChunkIndex index) const {
1995 switch (index) {
1996 case SpecializedIndex:
1997 return "Specialized";
1998 case SmallIndex:
1999 return "Small";
2000 case MediumIndex:
2001 return "Medium";
2002 case HumongousIndex:
2003 return "Humongous";
2004 default:
2005 return NULL;
2006 }
2007 }
2009 ChunkIndex ChunkManager::list_index(size_t size) {
2010 switch (size) {
2011 case SpecializedChunk:
2012 assert(SpecializedChunk == ClassSpecializedChunk,
2013 "Need branch for ClassSpecializedChunk");
2014 return SpecializedIndex;
2015 case SmallChunk:
2016 case ClassSmallChunk:
2017 return SmallIndex;
2018 case MediumChunk:
2019 case ClassMediumChunk:
2020 return MediumIndex;
2021 default:
2022 assert(size > MediumChunk || size > ClassMediumChunk,
2023 "Not a humongous chunk");
2024 return HumongousIndex;
2025 }
2026 }
2028 void SpaceManager::deallocate(MetaWord* p, size_t word_size) {
2029 assert_lock_strong(_lock);
2030 size_t min_size = TreeChunk<Metablock, FreeList>::min_size();
2031 assert(word_size >= min_size,
2032 err_msg("Should not deallocate dark matter " SIZE_FORMAT, word_size));
2033 block_freelists()->return_block(p, word_size);
2034 }
2036 // Adds a chunk to the list of chunks in use.
2037 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) {
2039 assert(new_chunk != NULL, "Should not be NULL");
2040 assert(new_chunk->next() == NULL, "Should not be on a list");
2042 new_chunk->reset_empty();
2044 // Find the correct list and and set the current
2045 // chunk for that list.
2046 ChunkIndex index = ChunkManager::list_index(new_chunk->word_size());
2048 if (index != HumongousIndex) {
2049 set_current_chunk(new_chunk);
2050 new_chunk->set_next(chunks_in_use(index));
2051 set_chunks_in_use(index, new_chunk);
2052 } else {
2053 // For null class loader data and DumpSharedSpaces, the first chunk isn't
2054 // small, so small will be null. Link this first chunk as the current
2055 // chunk.
2056 if (make_current) {
2057 // Set as the current chunk but otherwise treat as a humongous chunk.
2058 set_current_chunk(new_chunk);
2059 }
2060 // Link at head. The _current_chunk only points to a humongous chunk for
2061 // the null class loader metaspace (class and data virtual space managers)
2062 // any humongous chunks so will not point to the tail
2063 // of the humongous chunks list.
2064 new_chunk->set_next(chunks_in_use(HumongousIndex));
2065 set_chunks_in_use(HumongousIndex, new_chunk);
2067 assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency");
2068 }
2070 assert(new_chunk->is_empty(), "Not ready for reuse");
2071 if (TraceMetadataChunkAllocation && Verbose) {
2072 gclog_or_tty->print("SpaceManager::add_chunk: %d) ",
2073 sum_count_in_chunks_in_use());
2074 new_chunk->print_on(gclog_or_tty);
2075 vs_list()->chunk_manager()->locked_print_free_chunks(tty);
2076 }
2077 }
2079 Metachunk* SpaceManager::get_new_chunk(size_t word_size,
2080 size_t grow_chunks_by_words) {
2082 Metachunk* next = vs_list()->get_new_chunk(word_size,
2083 grow_chunks_by_words,
2084 medium_chunk_bunch());
2086 if (TraceMetadataHumongousAllocation &&
2087 SpaceManager::is_humongous(next->word_size())) {
2088 gclog_or_tty->print_cr(" new humongous chunk word size " PTR_FORMAT,
2089 next->word_size());
2090 }
2092 return next;
2093 }
2095 MetaWord* SpaceManager::allocate(size_t word_size) {
2096 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2098 // If only the dictionary is going to be used (i.e., no
2099 // indexed free list), then there is a minimum size requirement.
2100 // MinChunkSize is a placeholder for the real minimum size JJJ
2101 size_t byte_size = word_size * BytesPerWord;
2103 size_t byte_size_with_overhead = byte_size + Metablock::overhead();
2105 size_t raw_bytes_size = MAX2(byte_size_with_overhead,
2106 Metablock::min_block_byte_size());
2107 raw_bytes_size = ARENA_ALIGN(raw_bytes_size);
2108 size_t raw_word_size = raw_bytes_size / BytesPerWord;
2109 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem");
2111 BlockFreelist* fl = block_freelists();
2112 MetaWord* p = NULL;
2113 // Allocation from the dictionary is expensive in the sense that
2114 // the dictionary has to be searched for a size. Don't allocate
2115 // from the dictionary until it starts to get fat. Is this
2116 // a reasonable policy? Maybe an skinny dictionary is fast enough
2117 // for allocations. Do some profiling. JJJ
2118 if (fl->total_size() > allocation_from_dictionary_limit) {
2119 p = fl->get_block(raw_word_size);
2120 }
2121 if (p == NULL) {
2122 p = allocate_work(raw_word_size);
2123 }
2124 Metadebug::deallocate_block_a_lot(this, raw_word_size);
2126 return p;
2127 }
2129 // Returns the address of spaced allocated for "word_size".
2130 // This methods does not know about blocks (Metablocks)
2131 MetaWord* SpaceManager::allocate_work(size_t word_size) {
2132 assert_lock_strong(_lock);
2133 #ifdef ASSERT
2134 if (Metadebug::test_metadata_failure()) {
2135 return NULL;
2136 }
2137 #endif
2138 // Is there space in the current chunk?
2139 MetaWord* result = NULL;
2141 // For DumpSharedSpaces, only allocate out of the current chunk which is
2142 // never null because we gave it the size we wanted. Caller reports out
2143 // of memory if this returns null.
2144 if (DumpSharedSpaces) {
2145 assert(current_chunk() != NULL, "should never happen");
2146 inc_allocation_total(word_size);
2147 return current_chunk()->allocate(word_size); // caller handles null result
2148 }
2149 if (current_chunk() != NULL) {
2150 result = current_chunk()->allocate(word_size);
2151 }
2153 if (result == NULL) {
2154 result = grow_and_allocate(word_size);
2155 }
2156 if (result > 0) {
2157 inc_allocation_total(word_size);
2158 assert(result != (MetaWord*) chunks_in_use(MediumIndex),
2159 "Head of the list is being allocated");
2160 }
2162 return result;
2163 }
2165 void SpaceManager::verify() {
2166 // If there are blocks in the dictionary, then
2167 // verfication of chunks does not work since
2168 // being in the dictionary alters a chunk.
2169 if (block_freelists()->total_size() == 0) {
2170 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2171 Metachunk* curr = chunks_in_use(i);
2172 while (curr != NULL) {
2173 curr->verify();
2174 verify_chunk_size(curr);
2175 curr = curr->next();
2176 }
2177 }
2178 }
2179 }
2181 void SpaceManager::verify_chunk_size(Metachunk* chunk) {
2182 assert(is_humongous(chunk->word_size()) ||
2183 chunk->word_size() == medium_chunk_size() ||
2184 chunk->word_size() == small_chunk_size() ||
2185 chunk->word_size() == specialized_chunk_size(),
2186 "Chunk size is wrong");
2187 return;
2188 }
2190 #ifdef ASSERT
2191 void SpaceManager::verify_allocation_total() {
2192 // Verification is only guaranteed at a safepoint.
2193 if (SafepointSynchronize::is_at_safepoint()) {
2194 gclog_or_tty->print_cr("Chunk " PTR_FORMAT " allocation_total " SIZE_FORMAT
2195 " sum_used_in_chunks_in_use " SIZE_FORMAT,
2196 this,
2197 allocation_total(),
2198 sum_used_in_chunks_in_use());
2199 }
2200 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2201 assert(allocation_total() == sum_used_in_chunks_in_use(),
2202 err_msg("allocation total is not consistent " SIZE_FORMAT
2203 " vs " SIZE_FORMAT,
2204 allocation_total(), sum_used_in_chunks_in_use()));
2205 }
2207 #endif
2209 void SpaceManager::dump(outputStream* const out) const {
2210 size_t curr_total = 0;
2211 size_t waste = 0;
2212 uint i = 0;
2213 size_t used = 0;
2214 size_t capacity = 0;
2216 // Add up statistics for all chunks in this SpaceManager.
2217 for (ChunkIndex index = ZeroIndex;
2218 index < NumberOfInUseLists;
2219 index = next_chunk_index(index)) {
2220 for (Metachunk* curr = chunks_in_use(index);
2221 curr != NULL;
2222 curr = curr->next()) {
2223 out->print("%d) ", i++);
2224 curr->print_on(out);
2225 if (TraceMetadataChunkAllocation && Verbose) {
2226 block_freelists()->print_on(out);
2227 }
2228 curr_total += curr->word_size();
2229 used += curr->used_word_size();
2230 capacity += curr->capacity_word_size();
2231 waste += curr->free_word_size() + curr->overhead();;
2232 }
2233 }
2235 size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size();
2236 // Free space isn't wasted.
2237 waste -= free;
2239 out->print_cr("total of all chunks " SIZE_FORMAT " used " SIZE_FORMAT
2240 " free " SIZE_FORMAT " capacity " SIZE_FORMAT
2241 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste);
2242 }
2244 #ifndef PRODUCT
2245 void SpaceManager::mangle_freed_chunks() {
2246 for (ChunkIndex index = ZeroIndex;
2247 index < NumberOfInUseLists;
2248 index = next_chunk_index(index)) {
2249 for (Metachunk* curr = chunks_in_use(index);
2250 curr != NULL;
2251 curr = curr->next()) {
2252 curr->mangle();
2253 }
2254 }
2255 }
2256 #endif // PRODUCT
2258 // MetaspaceAux
2260 size_t MetaspaceAux::used_in_bytes(Metaspace::MetadataType mdtype) {
2261 size_t used = 0;
2262 ClassLoaderDataGraphMetaspaceIterator iter;
2263 while (iter.repeat()) {
2264 Metaspace* msp = iter.get_next();
2265 // Sum allocation_total for each metaspace
2266 if (msp != NULL) {
2267 used += msp->used_words(mdtype);
2268 }
2269 }
2270 return used * BytesPerWord;
2271 }
2273 size_t MetaspaceAux::free_in_bytes(Metaspace::MetadataType mdtype) {
2274 size_t free = 0;
2275 ClassLoaderDataGraphMetaspaceIterator iter;
2276 while (iter.repeat()) {
2277 Metaspace* msp = iter.get_next();
2278 if (msp != NULL) {
2279 free += msp->free_words(mdtype);
2280 }
2281 }
2282 return free * BytesPerWord;
2283 }
2285 size_t MetaspaceAux::capacity_in_bytes(Metaspace::MetadataType mdtype) {
2286 size_t capacity = free_chunks_total(mdtype);
2287 ClassLoaderDataGraphMetaspaceIterator iter;
2288 while (iter.repeat()) {
2289 Metaspace* msp = iter.get_next();
2290 if (msp != NULL) {
2291 capacity += msp->capacity_words(mdtype);
2292 }
2293 }
2294 return capacity * BytesPerWord;
2295 }
2297 size_t MetaspaceAux::reserved_in_bytes(Metaspace::MetadataType mdtype) {
2298 size_t reserved = (mdtype == Metaspace::ClassType) ?
2299 Metaspace::class_space_list()->virtual_space_total() :
2300 Metaspace::space_list()->virtual_space_total();
2301 return reserved * BytesPerWord;
2302 }
2304 size_t MetaspaceAux::min_chunk_size() { return Metaspace::first_chunk_word_size(); }
2306 size_t MetaspaceAux::free_chunks_total(Metaspace::MetadataType mdtype) {
2307 ChunkManager* chunk = (mdtype == Metaspace::ClassType) ?
2308 Metaspace::class_space_list()->chunk_manager() :
2309 Metaspace::space_list()->chunk_manager();
2310 chunk->slow_verify();
2311 return chunk->free_chunks_total();
2312 }
2314 size_t MetaspaceAux::free_chunks_total_in_bytes(Metaspace::MetadataType mdtype) {
2315 return free_chunks_total(mdtype) * BytesPerWord;
2316 }
2318 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) {
2319 gclog_or_tty->print(", [Metaspace:");
2320 if (PrintGCDetails && Verbose) {
2321 gclog_or_tty->print(" " SIZE_FORMAT
2322 "->" SIZE_FORMAT
2323 "(" SIZE_FORMAT "/" SIZE_FORMAT ")",
2324 prev_metadata_used,
2325 used_in_bytes(),
2326 capacity_in_bytes(),
2327 reserved_in_bytes());
2328 } else {
2329 gclog_or_tty->print(" " SIZE_FORMAT "K"
2330 "->" SIZE_FORMAT "K"
2331 "(" SIZE_FORMAT "K/" SIZE_FORMAT "K)",
2332 prev_metadata_used / K,
2333 used_in_bytes()/ K,
2334 capacity_in_bytes()/K,
2335 reserved_in_bytes()/ K);
2336 }
2338 gclog_or_tty->print("]");
2339 }
2341 // This is printed when PrintGCDetails
2342 void MetaspaceAux::print_on(outputStream* out) {
2343 Metaspace::MetadataType ct = Metaspace::ClassType;
2344 Metaspace::MetadataType nct = Metaspace::NonClassType;
2346 out->print_cr(" Metaspace total "
2347 SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
2348 " reserved " SIZE_FORMAT "K",
2349 capacity_in_bytes()/K, used_in_bytes()/K, reserved_in_bytes()/K);
2350 out->print_cr(" data space "
2351 SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
2352 " reserved " SIZE_FORMAT "K",
2353 capacity_in_bytes(nct)/K, used_in_bytes(nct)/K, reserved_in_bytes(nct)/K);
2354 out->print_cr(" class space "
2355 SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
2356 " reserved " SIZE_FORMAT "K",
2357 capacity_in_bytes(ct)/K, used_in_bytes(ct)/K, reserved_in_bytes(ct)/K);
2358 }
2360 // Print information for class space and data space separately.
2361 // This is almost the same as above.
2362 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) {
2363 size_t free_chunks_capacity_bytes = free_chunks_total_in_bytes(mdtype);
2364 size_t capacity_bytes = capacity_in_bytes(mdtype);
2365 size_t used_bytes = used_in_bytes(mdtype);
2366 size_t free_bytes = free_in_bytes(mdtype);
2367 size_t used_and_free = used_bytes + free_bytes +
2368 free_chunks_capacity_bytes;
2369 out->print_cr(" Chunk accounting: used in chunks " SIZE_FORMAT
2370 "K + unused in chunks " SIZE_FORMAT "K + "
2371 " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT
2372 "K capacity in allocated chunks " SIZE_FORMAT "K",
2373 used_bytes / K,
2374 free_bytes / K,
2375 free_chunks_capacity_bytes / K,
2376 used_and_free / K,
2377 capacity_bytes / K);
2378 // Accounting can only be correct if we got the values during a safepoint
2379 assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong");
2380 }
2382 // Print total fragmentation for class and data metaspaces separately
2383 void MetaspaceAux::print_waste(outputStream* out) {
2385 size_t specialized_waste = 0, small_waste = 0, medium_waste = 0, large_waste = 0;
2386 size_t specialized_count = 0, small_count = 0, medium_count = 0, large_count = 0;
2387 size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0, cls_large_waste = 0;
2388 size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_large_count = 0;
2390 ClassLoaderDataGraphMetaspaceIterator iter;
2391 while (iter.repeat()) {
2392 Metaspace* msp = iter.get_next();
2393 if (msp != NULL) {
2394 specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2395 specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2396 small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2397 small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex);
2398 medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2399 medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex);
2400 large_waste += msp->vsm()->sum_waste_in_chunks_in_use(HumongousIndex);
2401 large_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2403 cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2404 cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2405 cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2406 cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex);
2407 cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2408 cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex);
2409 cls_large_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(HumongousIndex);
2410 cls_large_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2411 }
2412 }
2413 out->print_cr("Total fragmentation waste (words) doesn't count free space");
2414 out->print_cr(" data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2415 SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
2416 SIZE_FORMAT " medium(s) " SIZE_FORMAT,
2417 specialized_count, specialized_waste, small_count,
2418 small_waste, medium_count, medium_waste);
2419 out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2420 SIZE_FORMAT " small(s) " SIZE_FORMAT,
2421 cls_specialized_count, cls_specialized_waste,
2422 cls_small_count, cls_small_waste);
2423 }
2425 // Dump global metaspace things from the end of ClassLoaderDataGraph
2426 void MetaspaceAux::dump(outputStream* out) {
2427 out->print_cr("All Metaspace:");
2428 out->print("data space: "); print_on(out, Metaspace::NonClassType);
2429 out->print("class space: "); print_on(out, Metaspace::ClassType);
2430 print_waste(out);
2431 }
2433 void MetaspaceAux::verify_free_chunks() {
2434 Metaspace::space_list()->chunk_manager()->verify();
2435 Metaspace::class_space_list()->chunk_manager()->verify();
2436 }
2438 // Metaspace methods
2440 size_t Metaspace::_first_chunk_word_size = 0;
2441 size_t Metaspace::_first_class_chunk_word_size = 0;
2443 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) {
2444 initialize(lock, type);
2445 }
2447 Metaspace::~Metaspace() {
2448 delete _vsm;
2449 delete _class_vsm;
2450 }
2452 VirtualSpaceList* Metaspace::_space_list = NULL;
2453 VirtualSpaceList* Metaspace::_class_space_list = NULL;
2455 #define VIRTUALSPACEMULTIPLIER 2
2457 void Metaspace::global_initialize() {
2458 // Initialize the alignment for shared spaces.
2459 int max_alignment = os::vm_page_size();
2460 MetaspaceShared::set_max_alignment(max_alignment);
2462 if (DumpSharedSpaces) {
2463 SharedReadOnlySize = align_size_up(SharedReadOnlySize, max_alignment);
2464 SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment);
2465 SharedMiscDataSize = align_size_up(SharedMiscDataSize, max_alignment);
2466 SharedMiscCodeSize = align_size_up(SharedMiscCodeSize, max_alignment);
2468 // Initialize with the sum of the shared space sizes. The read-only
2469 // and read write metaspace chunks will be allocated out of this and the
2470 // remainder is the misc code and data chunks.
2471 size_t total = align_size_up(SharedReadOnlySize + SharedReadWriteSize +
2472 SharedMiscDataSize + SharedMiscCodeSize,
2473 os::vm_allocation_granularity());
2474 size_t word_size = total/wordSize;
2475 _space_list = new VirtualSpaceList(word_size);
2476 } else {
2477 // If using shared space, open the file that contains the shared space
2478 // and map in the memory before initializing the rest of metaspace (so
2479 // the addresses don't conflict)
2480 if (UseSharedSpaces) {
2481 FileMapInfo* mapinfo = new FileMapInfo();
2482 memset(mapinfo, 0, sizeof(FileMapInfo));
2484 // Open the shared archive file, read and validate the header. If
2485 // initialization fails, shared spaces [UseSharedSpaces] are
2486 // disabled and the file is closed.
2487 // Map in spaces now also
2488 if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) {
2489 FileMapInfo::set_current_info(mapinfo);
2490 } else {
2491 assert(!mapinfo->is_open() && !UseSharedSpaces,
2492 "archive file not closed or shared spaces not disabled.");
2493 }
2494 }
2496 // Initialize these before initializing the VirtualSpaceList
2497 _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord;
2498 _first_chunk_word_size = align_word_size_up(_first_chunk_word_size);
2499 // Make the first class chunk bigger than a medium chunk so it's not put
2500 // on the medium chunk list. The next chunk will be small and progress
2501 // from there. This size calculated by -version.
2502 _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6,
2503 (ClassMetaspaceSize/BytesPerWord)*2);
2504 _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size);
2505 // Arbitrarily set the initial virtual space to a multiple
2506 // of the boot class loader size.
2507 size_t word_size = VIRTUALSPACEMULTIPLIER * first_chunk_word_size();
2508 // Initialize the list of virtual spaces.
2509 _space_list = new VirtualSpaceList(word_size);
2510 }
2511 }
2513 // For UseCompressedKlassPointers the class space is reserved as a piece of the
2514 // Java heap because the compression algorithm is the same for each. The
2515 // argument passed in is at the top of the compressed space
2516 void Metaspace::initialize_class_space(ReservedSpace rs) {
2517 // The reserved space size may be bigger because of alignment, esp with UseLargePages
2518 assert(rs.size() >= ClassMetaspaceSize,
2519 err_msg(SIZE_FORMAT " != " UINTX_FORMAT, rs.size(), ClassMetaspaceSize));
2520 _class_space_list = new VirtualSpaceList(rs);
2521 }
2523 void Metaspace::initialize(Mutex* lock,
2524 MetaspaceType type) {
2526 assert(space_list() != NULL,
2527 "Metadata VirtualSpaceList has not been initialized");
2529 _vsm = new SpaceManager(lock, space_list());
2530 if (_vsm == NULL) {
2531 return;
2532 }
2533 size_t word_size;
2534 size_t class_word_size;
2535 vsm()->get_initial_chunk_sizes(type,
2536 &word_size,
2537 &class_word_size);
2539 assert(class_space_list() != NULL,
2540 "Class VirtualSpaceList has not been initialized");
2542 // Allocate SpaceManager for classes.
2543 _class_vsm = new SpaceManager(lock, class_space_list());
2544 if (_class_vsm == NULL) {
2545 return;
2546 }
2548 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
2550 // Allocate chunk for metadata objects
2551 Metachunk* new_chunk =
2552 space_list()->get_initialization_chunk(word_size,
2553 vsm()->medium_chunk_bunch());
2554 assert(!DumpSharedSpaces || new_chunk != NULL, "should have enough space for both chunks");
2555 if (new_chunk != NULL) {
2556 // Add to this manager's list of chunks in use and current_chunk().
2557 vsm()->add_chunk(new_chunk, true);
2558 }
2560 // Allocate chunk for class metadata objects
2561 Metachunk* class_chunk =
2562 class_space_list()->get_initialization_chunk(class_word_size,
2563 class_vsm()->medium_chunk_bunch());
2564 if (class_chunk != NULL) {
2565 class_vsm()->add_chunk(class_chunk, true);
2566 }
2567 }
2569 size_t Metaspace::align_word_size_up(size_t word_size) {
2570 size_t byte_size = word_size * wordSize;
2571 return ReservedSpace::allocation_align_size_up(byte_size) / wordSize;
2572 }
2574 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) {
2575 // DumpSharedSpaces doesn't use class metadata area (yet)
2576 if (mdtype == ClassType && !DumpSharedSpaces) {
2577 return class_vsm()->allocate(word_size);
2578 } else {
2579 return vsm()->allocate(word_size);
2580 }
2581 }
2583 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) {
2584 MetaWord* result;
2585 MetaspaceGC::set_expand_after_GC(true);
2586 size_t before_inc = MetaspaceGC::capacity_until_GC();
2587 size_t delta_words = MetaspaceGC::delta_capacity_until_GC(word_size);
2588 MetaspaceGC::inc_capacity_until_GC(delta_words);
2589 if (PrintGCDetails && Verbose) {
2590 gclog_or_tty->print_cr("Increase capacity to GC from " SIZE_FORMAT
2591 " to " SIZE_FORMAT, before_inc, MetaspaceGC::capacity_until_GC());
2592 }
2594 result = allocate(word_size, mdtype);
2596 return result;
2597 }
2599 // Space allocated in the Metaspace. This may
2600 // be across several metadata virtual spaces.
2601 char* Metaspace::bottom() const {
2602 assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces");
2603 return (char*)vsm()->current_chunk()->bottom();
2604 }
2606 size_t Metaspace::used_words(MetadataType mdtype) const {
2607 // return vsm()->allocation_total();
2608 return mdtype == ClassType ? class_vsm()->sum_used_in_chunks_in_use() :
2609 vsm()->sum_used_in_chunks_in_use(); // includes overhead!
2610 }
2612 size_t Metaspace::free_words(MetadataType mdtype) const {
2613 return mdtype == ClassType ? class_vsm()->sum_free_in_chunks_in_use() :
2614 vsm()->sum_free_in_chunks_in_use();
2615 }
2617 // Space capacity in the Metaspace. It includes
2618 // space in the list of chunks from which allocations
2619 // have been made. Don't include space in the global freelist and
2620 // in the space available in the dictionary which
2621 // is already counted in some chunk.
2622 size_t Metaspace::capacity_words(MetadataType mdtype) const {
2623 return mdtype == ClassType ? class_vsm()->sum_capacity_in_chunks_in_use() :
2624 vsm()->sum_capacity_in_chunks_in_use();
2625 }
2627 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
2628 if (SafepointSynchronize::is_at_safepoint()) {
2629 assert(Thread::current()->is_VM_thread(), "should be the VM thread");
2630 // Don't take Heap_lock
2631 MutexLocker ml(vsm()->lock());
2632 if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
2633 // Dark matter. Too small for dictionary.
2634 #ifdef ASSERT
2635 Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
2636 #endif
2637 return;
2638 }
2639 if (is_class) {
2640 class_vsm()->deallocate(ptr, word_size);
2641 } else {
2642 vsm()->deallocate(ptr, word_size);
2643 }
2644 } else {
2645 MutexLocker ml(vsm()->lock());
2647 if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
2648 // Dark matter. Too small for dictionary.
2649 #ifdef ASSERT
2650 Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
2651 #endif
2652 return;
2653 }
2654 if (is_class) {
2655 class_vsm()->deallocate(ptr, word_size);
2656 } else {
2657 vsm()->deallocate(ptr, word_size);
2658 }
2659 }
2660 }
2662 Metablock* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size,
2663 bool read_only, MetadataType mdtype, TRAPS) {
2664 if (HAS_PENDING_EXCEPTION) {
2665 assert(false, "Should not allocate with exception pending");
2666 return NULL; // caller does a CHECK_NULL too
2667 }
2669 // SSS: Should we align the allocations and make sure the sizes are aligned.
2670 MetaWord* result = NULL;
2672 assert(loader_data != NULL, "Should never pass around a NULL loader_data. "
2673 "ClassLoaderData::the_null_class_loader_data() should have been used.");
2674 // Allocate in metaspaces without taking out a lock, because it deadlocks
2675 // with the SymbolTable_lock. Dumping is single threaded for now. We'll have
2676 // to revisit this for application class data sharing.
2677 if (DumpSharedSpaces) {
2678 if (read_only) {
2679 result = loader_data->ro_metaspace()->allocate(word_size, NonClassType);
2680 } else {
2681 result = loader_data->rw_metaspace()->allocate(word_size, NonClassType);
2682 }
2683 if (result == NULL) {
2684 report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite);
2685 }
2686 return Metablock::initialize(result, word_size);
2687 }
2689 result = loader_data->metaspace_non_null()->allocate(word_size, mdtype);
2691 if (result == NULL) {
2692 // Try to clean out some memory and retry.
2693 result =
2694 Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation(
2695 loader_data, word_size, mdtype);
2697 // If result is still null, we are out of memory.
2698 if (result == NULL) {
2699 if (Verbose && TraceMetadataChunkAllocation) {
2700 gclog_or_tty->print_cr("Metaspace allocation failed for size "
2701 SIZE_FORMAT, word_size);
2702 if (loader_data->metaspace_or_null() != NULL) loader_data->metaspace_or_null()->dump(gclog_or_tty);
2703 MetaspaceAux::dump(gclog_or_tty);
2704 }
2705 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
2706 report_java_out_of_memory("Metadata space");
2708 if (JvmtiExport::should_post_resource_exhausted()) {
2709 JvmtiExport::post_resource_exhausted(
2710 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
2711 "Metadata space");
2712 }
2713 THROW_OOP_0(Universe::out_of_memory_error_perm_gen());
2714 }
2715 }
2716 return Metablock::initialize(result, word_size);
2717 }
2719 void Metaspace::print_on(outputStream* out) const {
2720 // Print both class virtual space counts and metaspace.
2721 if (Verbose) {
2722 vsm()->print_on(out);
2723 class_vsm()->print_on(out);
2724 }
2725 }
2727 bool Metaspace::contains(const void * ptr) {
2728 if (MetaspaceShared::is_in_shared_space(ptr)) {
2729 return true;
2730 }
2731 // This is checked while unlocked. As long as the virtualspaces are added
2732 // at the end, the pointer will be in one of them. The virtual spaces
2733 // aren't deleted presently. When they are, some sort of locking might
2734 // be needed. Note, locking this can cause inversion problems with the
2735 // caller in MetaspaceObj::is_metadata() function.
2736 return space_list()->contains(ptr) || class_space_list()->contains(ptr);
2737 }
2739 void Metaspace::verify() {
2740 vsm()->verify();
2741 class_vsm()->verify();
2742 }
2744 void Metaspace::dump(outputStream* const out) const {
2745 if (UseMallocOnly) {
2746 // Just print usage for now
2747 out->print_cr("usage %d", used_words(Metaspace::NonClassType));
2748 }
2749 out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, vsm());
2750 vsm()->dump(out);
2751 out->print_cr("\nClass space manager: " INTPTR_FORMAT, class_vsm());
2752 class_vsm()->dump(out);
2753 }