Thu, 07 Feb 2013 16:05:48 -0500
Merge
1 /*
2 * Copyright (c) 2011, 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24 #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;
55 const size_t metadata_deallocate = 0xf5f5f5f5;
57 MetaWord* last_allocated = 0;
59 // Used in declarations in SpaceManager and ChunkManager
60 enum ChunkIndex {
61 ZeroIndex = 0,
62 SpecializedIndex = ZeroIndex,
63 SmallIndex = SpecializedIndex + 1,
64 MediumIndex = SmallIndex + 1,
65 HumongousIndex = MediumIndex + 1,
66 NumberOfFreeLists = 3,
67 NumberOfInUseLists = 4
68 };
70 enum ChunkSizes { // in words.
71 ClassSpecializedChunk = 128,
72 SpecializedChunk = 128,
73 ClassSmallChunk = 256,
74 SmallChunk = 512,
75 ClassMediumChunk = 1 * K,
76 MediumChunk = 8 * K,
77 HumongousChunkGranularity = 8
78 };
80 static ChunkIndex next_chunk_index(ChunkIndex i) {
81 assert(i < NumberOfInUseLists, "Out of bound");
82 return (ChunkIndex) (i+1);
83 }
85 // Originally _capacity_until_GC was set to MetaspaceSize here but
86 // the default MetaspaceSize before argument processing was being
87 // used which was not the desired value. See the code
88 // in should_expand() to see how the initialization is handled
89 // now.
90 size_t MetaspaceGC::_capacity_until_GC = 0;
91 bool MetaspaceGC::_expand_after_GC = false;
92 uint MetaspaceGC::_shrink_factor = 0;
93 bool MetaspaceGC::_should_concurrent_collect = false;
95 // Blocks of space for metadata are allocated out of Metachunks.
96 //
97 // Metachunk are allocated out of MetadataVirtualspaces and once
98 // allocated there is no explicit link between a Metachunk and
99 // the MetadataVirtualspaces from which it was allocated.
100 //
101 // Each SpaceManager maintains a
102 // list of the chunks it is using and the current chunk. The current
103 // chunk is the chunk from which allocations are done. Space freed in
104 // a chunk is placed on the free list of blocks (BlockFreelist) and
105 // reused from there.
107 // Pointer to list of Metachunks.
108 class ChunkList VALUE_OBJ_CLASS_SPEC {
109 // List of free chunks
110 Metachunk* _head;
112 public:
113 // Constructor
114 ChunkList() : _head(NULL) {}
116 // Accessors
117 Metachunk* head() { return _head; }
118 void set_head(Metachunk* v) { _head = v; }
120 // Link at head of the list
121 void add_at_head(Metachunk* head, Metachunk* tail);
122 void add_at_head(Metachunk* head);
124 size_t sum_list_size();
125 size_t sum_list_count();
126 size_t sum_list_capacity();
127 };
129 // Manages the global free lists of chunks.
130 // Has three lists of free chunks, and a total size and
131 // count that includes all three
133 class ChunkManager VALUE_OBJ_CLASS_SPEC {
135 // Free list of chunks of different sizes.
136 // SmallChunk
137 // MediumChunk
138 // HumongousChunk
139 ChunkList _free_chunks[NumberOfFreeLists];
142 // HumongousChunk
143 ChunkTreeDictionary _humongous_dictionary;
145 // ChunkManager in all lists of this type
146 size_t _free_chunks_total;
147 size_t _free_chunks_count;
149 void dec_free_chunks_total(size_t v) {
150 assert(_free_chunks_count > 0 &&
151 _free_chunks_total > 0,
152 "About to go negative");
153 Atomic::add_ptr(-1, &_free_chunks_count);
154 jlong minus_v = (jlong) - (jlong) v;
155 Atomic::add_ptr(minus_v, &_free_chunks_total);
156 }
158 // Debug support
160 size_t sum_free_chunks();
161 size_t sum_free_chunks_count();
163 void locked_verify_free_chunks_total();
164 void slow_locked_verify_free_chunks_total() {
165 if (metaspace_slow_verify) {
166 locked_verify_free_chunks_total();
167 }
168 }
169 void locked_verify_free_chunks_count();
170 void slow_locked_verify_free_chunks_count() {
171 if (metaspace_slow_verify) {
172 locked_verify_free_chunks_count();
173 }
174 }
175 void verify_free_chunks_count();
177 public:
179 ChunkManager() : _free_chunks_total(0), _free_chunks_count(0) {}
181 // add or delete (return) a chunk to the global freelist.
182 Metachunk* chunk_freelist_allocate(size_t word_size);
183 void chunk_freelist_deallocate(Metachunk* chunk);
185 // Map a size to a list index assuming that there are lists
186 // for special, small, medium, and humongous chunks.
187 static ChunkIndex list_index(size_t size);
189 // Total of the space in the free chunks list
190 size_t free_chunks_total();
191 size_t free_chunks_total_in_bytes();
193 // Number of chunks in the free chunks list
194 size_t free_chunks_count();
196 void inc_free_chunks_total(size_t v, size_t count = 1) {
197 Atomic::add_ptr(count, &_free_chunks_count);
198 Atomic::add_ptr(v, &_free_chunks_total);
199 }
200 ChunkTreeDictionary* humongous_dictionary() {
201 return &_humongous_dictionary;
202 }
204 ChunkList* free_chunks(ChunkIndex index);
206 // Returns the list for the given chunk word size.
207 ChunkList* find_free_chunks_list(size_t word_size);
209 // Add and remove from a list by size. Selects
210 // list based on size of chunk.
211 void free_chunks_put(Metachunk* chuck);
212 Metachunk* free_chunks_get(size_t chunk_word_size);
214 // Debug support
215 void verify();
216 void slow_verify() {
217 if (metaspace_slow_verify) {
218 verify();
219 }
220 }
221 void locked_verify();
222 void slow_locked_verify() {
223 if (metaspace_slow_verify) {
224 locked_verify();
225 }
226 }
227 void verify_free_chunks_total();
229 void locked_print_free_chunks(outputStream* st);
230 void locked_print_sum_free_chunks(outputStream* st);
232 void print_on(outputStream* st);
233 };
236 // Used to manage the free list of Metablocks (a block corresponds
237 // to the allocation of a quantum of metadata).
238 class BlockFreelist VALUE_OBJ_CLASS_SPEC {
239 BlockTreeDictionary* _dictionary;
240 static Metablock* initialize_free_chunk(MetaWord* p, size_t word_size);
242 // Accessors
243 BlockTreeDictionary* dictionary() const { return _dictionary; }
245 public:
246 BlockFreelist();
247 ~BlockFreelist();
249 // Get and return a block to the free list
250 MetaWord* get_block(size_t word_size);
251 void return_block(MetaWord* p, size_t word_size);
253 size_t total_size() {
254 if (dictionary() == NULL) {
255 return 0;
256 } else {
257 return dictionary()->total_size();
258 }
259 }
261 void print_on(outputStream* st) const;
262 };
264 class VirtualSpaceNode : public CHeapObj<mtClass> {
265 friend class VirtualSpaceList;
267 // Link to next VirtualSpaceNode
268 VirtualSpaceNode* _next;
270 // total in the VirtualSpace
271 MemRegion _reserved;
272 ReservedSpace _rs;
273 VirtualSpace _virtual_space;
274 MetaWord* _top;
276 // Convenience functions for logical bottom and end
277 MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); }
278 MetaWord* end() const { return (MetaWord*) _virtual_space.high(); }
280 // Convenience functions to access the _virtual_space
281 char* low() const { return virtual_space()->low(); }
282 char* high() const { return virtual_space()->high(); }
284 public:
286 VirtualSpaceNode(size_t byte_size);
287 VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs) {}
288 ~VirtualSpaceNode();
290 // address of next available space in _virtual_space;
291 // Accessors
292 VirtualSpaceNode* next() { return _next; }
293 void set_next(VirtualSpaceNode* v) { _next = v; }
295 void set_reserved(MemRegion const v) { _reserved = v; }
296 void set_top(MetaWord* v) { _top = v; }
298 // Accessors
299 MemRegion* reserved() { return &_reserved; }
300 VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; }
302 // Returns true if "word_size" is available in the virtual space
303 bool is_available(size_t word_size) { return _top + word_size <= end(); }
305 MetaWord* top() const { return _top; }
306 void inc_top(size_t word_size) { _top += word_size; }
308 // used and capacity in this single entry in the list
309 size_t used_words_in_vs() const;
310 size_t capacity_words_in_vs() const;
312 bool initialize();
314 // get space from the virtual space
315 Metachunk* take_from_committed(size_t chunk_word_size);
317 // Allocate a chunk from the virtual space and return it.
318 Metachunk* get_chunk_vs(size_t chunk_word_size);
319 Metachunk* get_chunk_vs_with_expand(size_t chunk_word_size);
321 // Expands/shrinks the committed space in a virtual space. Delegates
322 // to Virtualspace
323 bool expand_by(size_t words, bool pre_touch = false);
324 bool shrink_by(size_t words);
326 #ifdef ASSERT
327 // Debug support
328 static void verify_virtual_space_total();
329 static void verify_virtual_space_count();
330 void mangle();
331 #endif
333 void print_on(outputStream* st) const;
334 };
336 // byte_size is the size of the associated virtualspace.
337 VirtualSpaceNode::VirtualSpaceNode(size_t byte_size) : _top(NULL), _next(NULL), _rs(0) {
338 // This allocates memory with mmap. For DumpSharedspaces, allocate the
339 // space at low memory so that other shared images don't conflict.
340 // This is the same address as memory needed for UseCompressedOops but
341 // compressed oops don't work with CDS (offsets in metadata are wrong), so
342 // borrow the same address.
343 if (DumpSharedSpaces) {
344 char* shared_base = (char*)HeapBaseMinAddress;
345 _rs = ReservedSpace(byte_size, 0, false, shared_base, 0);
346 if (_rs.is_reserved()) {
347 assert(_rs.base() == shared_base, "should match");
348 } else {
349 // If we are dumping the heap, then allocate a wasted block of address
350 // space in order to push the heap to a lower address. This extra
351 // address range allows for other (or larger) libraries to be loaded
352 // without them occupying the space required for the shared spaces.
353 uintx reserved = 0;
354 uintx block_size = 64*1024*1024;
355 while (reserved < SharedDummyBlockSize) {
356 char* dummy = os::reserve_memory(block_size);
357 reserved += block_size;
358 }
359 _rs = ReservedSpace(byte_size);
360 }
361 MetaspaceShared::set_shared_rs(&_rs);
362 } else {
363 _rs = ReservedSpace(byte_size);
364 }
366 MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass);
367 }
369 // List of VirtualSpaces for metadata allocation.
370 // It has a _next link for singly linked list and a MemRegion
371 // for total space in the VirtualSpace.
372 class VirtualSpaceList : public CHeapObj<mtClass> {
373 friend class VirtualSpaceNode;
375 enum VirtualSpaceSizes {
376 VirtualSpaceSize = 256 * K
377 };
379 // Global list of virtual spaces
380 // Head of the list
381 VirtualSpaceNode* _virtual_space_list;
382 // virtual space currently being used for allocations
383 VirtualSpaceNode* _current_virtual_space;
384 // Free chunk list for all other metadata
385 ChunkManager _chunk_manager;
387 // Can this virtual list allocate >1 spaces? Also, used to determine
388 // whether to allocate unlimited small chunks in this virtual space
389 bool _is_class;
390 bool can_grow() const { return !is_class() || !UseCompressedKlassPointers; }
392 // Sum of space in all virtual spaces and number of virtual spaces
393 size_t _virtual_space_total;
394 size_t _virtual_space_count;
396 ~VirtualSpaceList();
398 VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; }
400 void set_virtual_space_list(VirtualSpaceNode* v) {
401 _virtual_space_list = v;
402 }
403 void set_current_virtual_space(VirtualSpaceNode* v) {
404 _current_virtual_space = v;
405 }
407 void link_vs(VirtualSpaceNode* new_entry, size_t vs_word_size);
409 // Get another virtual space and add it to the list. This
410 // is typically prompted by a failed attempt to allocate a chunk
411 // and is typically followed by the allocation of a chunk.
412 bool grow_vs(size_t vs_word_size);
414 public:
415 VirtualSpaceList(size_t word_size);
416 VirtualSpaceList(ReservedSpace rs);
418 Metachunk* get_new_chunk(size_t word_size,
419 size_t grow_chunks_by_words,
420 size_t medium_chunk_bunch);
422 // Get the first chunk for a Metaspace. Used for
423 // special cases such as the boot class loader, reflection
424 // class loader and anonymous class loader.
425 Metachunk* get_initialization_chunk(size_t word_size, size_t chunk_bunch);
427 VirtualSpaceNode* current_virtual_space() {
428 return _current_virtual_space;
429 }
431 ChunkManager* chunk_manager() { return &_chunk_manager; }
432 bool is_class() const { return _is_class; }
434 // Allocate the first virtualspace.
435 void initialize(size_t word_size);
437 size_t virtual_space_total() { return _virtual_space_total; }
438 void inc_virtual_space_total(size_t v) {
439 Atomic::add_ptr(v, &_virtual_space_total);
440 }
442 size_t virtual_space_count() { return _virtual_space_count; }
443 void inc_virtual_space_count() {
444 Atomic::inc_ptr(&_virtual_space_count);
445 }
447 // Used and capacity in the entire list of virtual spaces.
448 // These are global values shared by all Metaspaces
449 size_t capacity_words_sum();
450 size_t capacity_bytes_sum() { return capacity_words_sum() * BytesPerWord; }
451 size_t used_words_sum();
452 size_t used_bytes_sum() { return used_words_sum() * BytesPerWord; }
454 bool contains(const void *ptr);
456 void print_on(outputStream* st) const;
458 class VirtualSpaceListIterator : public StackObj {
459 VirtualSpaceNode* _virtual_spaces;
460 public:
461 VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) :
462 _virtual_spaces(virtual_spaces) {}
464 bool repeat() {
465 return _virtual_spaces != NULL;
466 }
468 VirtualSpaceNode* get_next() {
469 VirtualSpaceNode* result = _virtual_spaces;
470 if (_virtual_spaces != NULL) {
471 _virtual_spaces = _virtual_spaces->next();
472 }
473 return result;
474 }
475 };
476 };
478 class Metadebug : AllStatic {
479 // Debugging support for Metaspaces
480 static int _deallocate_block_a_lot_count;
481 static int _deallocate_chunk_a_lot_count;
482 static int _allocation_fail_alot_count;
484 public:
485 static int deallocate_block_a_lot_count() {
486 return _deallocate_block_a_lot_count;
487 }
488 static void set_deallocate_block_a_lot_count(int v) {
489 _deallocate_block_a_lot_count = v;
490 }
491 static void inc_deallocate_block_a_lot_count() {
492 _deallocate_block_a_lot_count++;
493 }
494 static int deallocate_chunk_a_lot_count() {
495 return _deallocate_chunk_a_lot_count;
496 }
497 static void reset_deallocate_chunk_a_lot_count() {
498 _deallocate_chunk_a_lot_count = 1;
499 }
500 static void inc_deallocate_chunk_a_lot_count() {
501 _deallocate_chunk_a_lot_count++;
502 }
504 static void init_allocation_fail_alot_count();
505 #ifdef ASSERT
506 static bool test_metadata_failure();
507 #endif
509 static void deallocate_chunk_a_lot(SpaceManager* sm,
510 size_t chunk_word_size);
511 static void deallocate_block_a_lot(SpaceManager* sm,
512 size_t chunk_word_size);
514 };
516 int Metadebug::_deallocate_block_a_lot_count = 0;
517 int Metadebug::_deallocate_chunk_a_lot_count = 0;
518 int Metadebug::_allocation_fail_alot_count = 0;
520 // SpaceManager - used by Metaspace to handle allocations
521 class SpaceManager : public CHeapObj<mtClass> {
522 friend class Metaspace;
523 friend class Metadebug;
525 private:
527 // protects allocations and contains.
528 Mutex* const _lock;
530 // Chunk related size
531 size_t _medium_chunk_bunch;
533 // List of chunks in use by this SpaceManager. Allocations
534 // are done from the current chunk. The list is used for deallocating
535 // chunks when the SpaceManager is freed.
536 Metachunk* _chunks_in_use[NumberOfInUseLists];
537 Metachunk* _current_chunk;
539 // Virtual space where allocation comes from.
540 VirtualSpaceList* _vs_list;
542 // Number of small chunks to allocate to a manager
543 // If class space manager, small chunks are unlimited
544 static uint const _small_chunk_limit;
545 bool has_small_chunk_limit() { return !vs_list()->is_class(); }
547 // Sum of all space in allocated chunks
548 size_t _allocation_total;
550 // Free lists of blocks are per SpaceManager since they
551 // are assumed to be in chunks in use by the SpaceManager
552 // and all chunks in use by a SpaceManager are freed when
553 // the class loader using the SpaceManager is collected.
554 BlockFreelist _block_freelists;
556 // protects virtualspace and chunk expansions
557 static const char* _expand_lock_name;
558 static const int _expand_lock_rank;
559 static Mutex* const _expand_lock;
561 private:
562 // Accessors
563 Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; }
564 void set_chunks_in_use(ChunkIndex index, Metachunk* v) { _chunks_in_use[index] = v; }
566 BlockFreelist* block_freelists() const {
567 return (BlockFreelist*) &_block_freelists;
568 }
570 VirtualSpaceList* vs_list() const { return _vs_list; }
572 Metachunk* current_chunk() const { return _current_chunk; }
573 void set_current_chunk(Metachunk* v) {
574 _current_chunk = v;
575 }
577 Metachunk* find_current_chunk(size_t word_size);
579 // Add chunk to the list of chunks in use
580 void add_chunk(Metachunk* v, bool make_current);
582 Mutex* lock() const { return _lock; }
584 const char* chunk_size_name(ChunkIndex index) const;
586 protected:
587 void initialize();
589 public:
590 SpaceManager(Mutex* lock,
591 VirtualSpaceList* vs_list);
592 ~SpaceManager();
594 enum ChunkMultiples {
595 MediumChunkMultiple = 4
596 };
598 // Accessors
599 size_t specialized_chunk_size() { return SpecializedChunk; }
600 size_t small_chunk_size() { return (size_t) vs_list()->is_class() ? ClassSmallChunk : SmallChunk; }
601 size_t medium_chunk_size() { return (size_t) vs_list()->is_class() ? ClassMediumChunk : MediumChunk; }
602 size_t medium_chunk_bunch() { return medium_chunk_size() * MediumChunkMultiple; }
604 size_t allocation_total() const { return _allocation_total; }
605 void inc_allocation_total(size_t v) { Atomic::add_ptr(v, &_allocation_total); }
606 bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); }
608 static Mutex* expand_lock() { return _expand_lock; }
610 // Set the sizes for the initial chunks.
611 void get_initial_chunk_sizes(Metaspace::MetaspaceType type,
612 size_t* chunk_word_size,
613 size_t* class_chunk_word_size);
615 size_t sum_capacity_in_chunks_in_use() const;
616 size_t sum_used_in_chunks_in_use() const;
617 size_t sum_free_in_chunks_in_use() const;
618 size_t sum_waste_in_chunks_in_use() const;
619 size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const;
621 size_t sum_count_in_chunks_in_use();
622 size_t sum_count_in_chunks_in_use(ChunkIndex i);
624 Metachunk* get_new_chunk(size_t word_size, size_t grow_chunks_by_words);
626 // Block allocation and deallocation.
627 // Allocates a block from the current chunk
628 MetaWord* allocate(size_t word_size);
630 // Helper for allocations
631 MetaWord* allocate_work(size_t word_size);
633 // Returns a block to the per manager freelist
634 void deallocate(MetaWord* p, size_t word_size);
636 // Based on the allocation size and a minimum chunk size,
637 // returned chunk size (for expanding space for chunk allocation).
638 size_t calc_chunk_size(size_t allocation_word_size);
640 // Called when an allocation from the current chunk fails.
641 // Gets a new chunk (may require getting a new virtual space),
642 // and allocates from that chunk.
643 MetaWord* grow_and_allocate(size_t word_size);
645 // debugging support.
647 void dump(outputStream* const out) const;
648 void print_on(outputStream* st) const;
649 void locked_print_chunks_in_use_on(outputStream* st) const;
651 void verify();
652 void verify_chunk_size(Metachunk* chunk);
653 NOT_PRODUCT(void mangle_freed_chunks();)
654 #ifdef ASSERT
655 void verify_allocation_total();
656 #endif
657 };
659 uint const SpaceManager::_small_chunk_limit = 4;
661 const char* SpaceManager::_expand_lock_name =
662 "SpaceManager chunk allocation lock";
663 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1;
664 Mutex* const SpaceManager::_expand_lock =
665 new Mutex(SpaceManager::_expand_lock_rank,
666 SpaceManager::_expand_lock_name,
667 Mutex::_allow_vm_block_flag);
669 // BlockFreelist methods
671 BlockFreelist::BlockFreelist() : _dictionary(NULL) {}
673 BlockFreelist::~BlockFreelist() {
674 if (_dictionary != NULL) {
675 if (Verbose && TraceMetadataChunkAllocation) {
676 _dictionary->print_free_lists(gclog_or_tty);
677 }
678 delete _dictionary;
679 }
680 }
682 Metablock* BlockFreelist::initialize_free_chunk(MetaWord* p, size_t word_size) {
683 Metablock* block = (Metablock*) p;
684 block->set_word_size(word_size);
685 block->set_prev(NULL);
686 block->set_next(NULL);
688 return block;
689 }
691 void BlockFreelist::return_block(MetaWord* p, size_t word_size) {
692 Metablock* free_chunk = initialize_free_chunk(p, word_size);
693 if (dictionary() == NULL) {
694 _dictionary = new BlockTreeDictionary();
695 }
696 dictionary()->return_chunk(free_chunk);
697 }
699 MetaWord* BlockFreelist::get_block(size_t word_size) {
700 if (dictionary() == NULL) {
701 return NULL;
702 }
704 if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
705 // Dark matter. Too small for dictionary.
706 return NULL;
707 }
709 Metablock* free_block =
710 dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::exactly);
711 if (free_block == NULL) {
712 return NULL;
713 }
715 return (MetaWord*) free_block;
716 }
718 void BlockFreelist::print_on(outputStream* st) const {
719 if (dictionary() == NULL) {
720 return;
721 }
722 dictionary()->print_free_lists(st);
723 }
725 // VirtualSpaceNode methods
727 VirtualSpaceNode::~VirtualSpaceNode() {
728 _rs.release();
729 }
731 size_t VirtualSpaceNode::used_words_in_vs() const {
732 return pointer_delta(top(), bottom(), sizeof(MetaWord));
733 }
735 // Space committed in the VirtualSpace
736 size_t VirtualSpaceNode::capacity_words_in_vs() const {
737 return pointer_delta(end(), bottom(), sizeof(MetaWord));
738 }
741 // Allocates the chunk from the virtual space only.
742 // This interface is also used internally for debugging. Not all
743 // chunks removed here are necessarily used for allocation.
744 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) {
745 // Bottom of the new chunk
746 MetaWord* chunk_limit = top();
747 assert(chunk_limit != NULL, "Not safe to call this method");
749 if (!is_available(chunk_word_size)) {
750 if (TraceMetadataChunkAllocation) {
751 tty->print("VirtualSpaceNode::take_from_committed() not available %d words ", chunk_word_size);
752 // Dump some information about the virtual space that is nearly full
753 print_on(tty);
754 }
755 return NULL;
756 }
758 // Take the space (bump top on the current virtual space).
759 inc_top(chunk_word_size);
761 // Point the chunk at the space
762 Metachunk* result = Metachunk::initialize(chunk_limit, chunk_word_size);
763 return result;
764 }
767 // Expand the virtual space (commit more of the reserved space)
768 bool VirtualSpaceNode::expand_by(size_t words, bool pre_touch) {
769 size_t bytes = words * BytesPerWord;
770 bool result = virtual_space()->expand_by(bytes, pre_touch);
771 if (TraceMetavirtualspaceAllocation && !result) {
772 gclog_or_tty->print_cr("VirtualSpaceNode::expand_by() failed "
773 "for byte size " SIZE_FORMAT, bytes);
774 virtual_space()->print();
775 }
776 return result;
777 }
779 // Shrink the virtual space (commit more of the reserved space)
780 bool VirtualSpaceNode::shrink_by(size_t words) {
781 size_t bytes = words * BytesPerWord;
782 virtual_space()->shrink_by(bytes);
783 return true;
784 }
786 // Add another chunk to the chunk list.
788 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) {
789 assert_lock_strong(SpaceManager::expand_lock());
790 Metachunk* result = NULL;
792 return take_from_committed(chunk_word_size);
793 }
795 Metachunk* VirtualSpaceNode::get_chunk_vs_with_expand(size_t chunk_word_size) {
796 assert_lock_strong(SpaceManager::expand_lock());
798 Metachunk* new_chunk = get_chunk_vs(chunk_word_size);
800 if (new_chunk == NULL) {
801 // Only a small part of the virtualspace is committed when first
802 // allocated so committing more here can be expected.
803 size_t page_size_words = os::vm_page_size() / BytesPerWord;
804 size_t aligned_expand_vs_by_words = align_size_up(chunk_word_size,
805 page_size_words);
806 expand_by(aligned_expand_vs_by_words, false);
807 new_chunk = get_chunk_vs(chunk_word_size);
808 }
809 return new_chunk;
810 }
812 bool VirtualSpaceNode::initialize() {
814 if (!_rs.is_reserved()) {
815 return false;
816 }
818 // An allocation out of this Virtualspace that is larger
819 // than an initial commit size can waste that initial committed
820 // space.
821 size_t committed_byte_size = 0;
822 bool result = virtual_space()->initialize(_rs, committed_byte_size);
823 if (result) {
824 set_top((MetaWord*)virtual_space()->low());
825 set_reserved(MemRegion((HeapWord*)_rs.base(),
826 (HeapWord*)(_rs.base() + _rs.size())));
828 assert(reserved()->start() == (HeapWord*) _rs.base(),
829 err_msg("Reserved start was not set properly " PTR_FORMAT
830 " != " PTR_FORMAT, reserved()->start(), _rs.base()));
831 assert(reserved()->word_size() == _rs.size() / BytesPerWord,
832 err_msg("Reserved size was not set properly " SIZE_FORMAT
833 " != " SIZE_FORMAT, reserved()->word_size(),
834 _rs.size() / BytesPerWord));
835 }
837 return result;
838 }
840 void VirtualSpaceNode::print_on(outputStream* st) const {
841 size_t used = used_words_in_vs();
842 size_t capacity = capacity_words_in_vs();
843 VirtualSpace* vs = virtual_space();
844 st->print_cr(" space @ " PTR_FORMAT " " SIZE_FORMAT "K, %3d%% used "
845 "[" PTR_FORMAT ", " PTR_FORMAT ", "
846 PTR_FORMAT ", " PTR_FORMAT ")",
847 vs, capacity / K,
848 capacity == 0 ? 0 : used * 100 / capacity,
849 bottom(), top(), end(),
850 vs->high_boundary());
851 }
853 #ifdef ASSERT
854 void VirtualSpaceNode::mangle() {
855 size_t word_size = capacity_words_in_vs();
856 Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1);
857 }
858 #endif // ASSERT
860 // VirtualSpaceList methods
861 // Space allocated from the VirtualSpace
863 VirtualSpaceList::~VirtualSpaceList() {
864 VirtualSpaceListIterator iter(virtual_space_list());
865 while (iter.repeat()) {
866 VirtualSpaceNode* vsl = iter.get_next();
867 delete vsl;
868 }
869 }
871 size_t VirtualSpaceList::used_words_sum() {
872 size_t allocated_by_vs = 0;
873 VirtualSpaceListIterator iter(virtual_space_list());
874 while (iter.repeat()) {
875 VirtualSpaceNode* vsl = iter.get_next();
876 // Sum used region [bottom, top) in each virtualspace
877 allocated_by_vs += vsl->used_words_in_vs();
878 }
879 assert(allocated_by_vs >= chunk_manager()->free_chunks_total(),
880 err_msg("Total in free chunks " SIZE_FORMAT
881 " greater than total from virtual_spaces " SIZE_FORMAT,
882 allocated_by_vs, chunk_manager()->free_chunks_total()));
883 size_t used =
884 allocated_by_vs - chunk_manager()->free_chunks_total();
885 return used;
886 }
888 // Space available in all MetadataVirtualspaces allocated
889 // for metadata. This is the upper limit on the capacity
890 // of chunks allocated out of all the MetadataVirtualspaces.
891 size_t VirtualSpaceList::capacity_words_sum() {
892 size_t capacity = 0;
893 VirtualSpaceListIterator iter(virtual_space_list());
894 while (iter.repeat()) {
895 VirtualSpaceNode* vsl = iter.get_next();
896 capacity += vsl->capacity_words_in_vs();
897 }
898 return capacity;
899 }
901 VirtualSpaceList::VirtualSpaceList(size_t word_size ) :
902 _is_class(false),
903 _virtual_space_list(NULL),
904 _current_virtual_space(NULL),
905 _virtual_space_total(0),
906 _virtual_space_count(0) {
907 MutexLockerEx cl(SpaceManager::expand_lock(),
908 Mutex::_no_safepoint_check_flag);
909 bool initialization_succeeded = grow_vs(word_size);
911 assert(initialization_succeeded,
912 " VirtualSpaceList initialization should not fail");
913 }
915 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) :
916 _is_class(true),
917 _virtual_space_list(NULL),
918 _current_virtual_space(NULL),
919 _virtual_space_total(0),
920 _virtual_space_count(0) {
921 MutexLockerEx cl(SpaceManager::expand_lock(),
922 Mutex::_no_safepoint_check_flag);
923 VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs);
924 bool succeeded = class_entry->initialize();
925 assert(succeeded, " VirtualSpaceList initialization should not fail");
926 link_vs(class_entry, rs.size()/BytesPerWord);
927 }
929 // Allocate another meta virtual space and add it to the list.
930 bool VirtualSpaceList::grow_vs(size_t vs_word_size) {
931 assert_lock_strong(SpaceManager::expand_lock());
932 if (vs_word_size == 0) {
933 return false;
934 }
935 // Reserve the space
936 size_t vs_byte_size = vs_word_size * BytesPerWord;
937 assert(vs_byte_size % os::vm_page_size() == 0, "Not aligned");
939 // Allocate the meta virtual space and initialize it.
940 VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size);
941 if (!new_entry->initialize()) {
942 delete new_entry;
943 return false;
944 } else {
945 // ensure lock-free iteration sees fully initialized node
946 OrderAccess::storestore();
947 link_vs(new_entry, vs_word_size);
948 return true;
949 }
950 }
952 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry, size_t vs_word_size) {
953 if (virtual_space_list() == NULL) {
954 set_virtual_space_list(new_entry);
955 } else {
956 current_virtual_space()->set_next(new_entry);
957 }
958 set_current_virtual_space(new_entry);
959 inc_virtual_space_total(vs_word_size);
960 inc_virtual_space_count();
961 #ifdef ASSERT
962 new_entry->mangle();
963 #endif
964 if (TraceMetavirtualspaceAllocation && Verbose) {
965 VirtualSpaceNode* vsl = current_virtual_space();
966 vsl->print_on(tty);
967 }
968 }
970 Metachunk* VirtualSpaceList::get_new_chunk(size_t word_size,
971 size_t grow_chunks_by_words,
972 size_t medium_chunk_bunch) {
974 // Get a chunk from the chunk freelist
975 Metachunk* next = chunk_manager()->chunk_freelist_allocate(grow_chunks_by_words);
977 // Allocate a chunk out of the current virtual space.
978 if (next == NULL) {
979 next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
980 }
982 if (next == NULL) {
983 // Not enough room in current virtual space. Try to commit
984 // more space.
985 size_t expand_vs_by_words = MAX2(medium_chunk_bunch,
986 grow_chunks_by_words);
987 size_t page_size_words = os::vm_page_size() / BytesPerWord;
988 size_t aligned_expand_vs_by_words = align_size_up(expand_vs_by_words,
989 page_size_words);
990 bool vs_expanded =
991 current_virtual_space()->expand_by(aligned_expand_vs_by_words, false);
992 if (!vs_expanded) {
993 // Should the capacity of the metaspaces be expanded for
994 // this allocation? If it's the virtual space for classes and is
995 // being used for CompressedHeaders, don't allocate a new virtualspace.
996 if (can_grow() && MetaspaceGC::should_expand(this, word_size)) {
997 // Get another virtual space.
998 size_t grow_vs_words =
999 MAX2((size_t)VirtualSpaceSize, aligned_expand_vs_by_words);
1000 if (grow_vs(grow_vs_words)) {
1001 // Got it. It's on the list now. Get a chunk from it.
1002 next = current_virtual_space()->get_chunk_vs_with_expand(grow_chunks_by_words);
1003 }
1004 } else {
1005 // Allocation will fail and induce a GC
1006 if (TraceMetadataChunkAllocation && Verbose) {
1007 gclog_or_tty->print_cr("VirtualSpaceList::get_new_chunk():"
1008 " Fail instead of expand the metaspace");
1009 }
1010 }
1011 } else {
1012 // The virtual space expanded, get a new chunk
1013 next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
1014 assert(next != NULL, "Just expanded, should succeed");
1015 }
1016 }
1018 assert(next == NULL || (next->next() == NULL && next->prev() == NULL),
1019 "New chunk is still on some list");
1020 return next;
1021 }
1023 Metachunk* VirtualSpaceList::get_initialization_chunk(size_t chunk_word_size,
1024 size_t chunk_bunch) {
1025 // Get a chunk from the chunk freelist
1026 Metachunk* new_chunk = get_new_chunk(chunk_word_size,
1027 chunk_word_size,
1028 chunk_bunch);
1029 return new_chunk;
1030 }
1032 void VirtualSpaceList::print_on(outputStream* st) const {
1033 if (TraceMetadataChunkAllocation && Verbose) {
1034 VirtualSpaceListIterator iter(virtual_space_list());
1035 while (iter.repeat()) {
1036 VirtualSpaceNode* node = iter.get_next();
1037 node->print_on(st);
1038 }
1039 }
1040 }
1042 bool VirtualSpaceList::contains(const void *ptr) {
1043 VirtualSpaceNode* list = virtual_space_list();
1044 VirtualSpaceListIterator iter(list);
1045 while (iter.repeat()) {
1046 VirtualSpaceNode* node = iter.get_next();
1047 if (node->reserved()->contains(ptr)) {
1048 return true;
1049 }
1050 }
1051 return false;
1052 }
1055 // MetaspaceGC methods
1057 // VM_CollectForMetadataAllocation is the vm operation used to GC.
1058 // Within the VM operation after the GC the attempt to allocate the metadata
1059 // should succeed. If the GC did not free enough space for the metaspace
1060 // allocation, the HWM is increased so that another virtualspace will be
1061 // allocated for the metadata. With perm gen the increase in the perm
1062 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The
1063 // metaspace policy uses those as the small and large steps for the HWM.
1064 //
1065 // After the GC the compute_new_size() for MetaspaceGC is called to
1066 // resize the capacity of the metaspaces. The current implementation
1067 // is based on the flags MinHeapFreeRatio and MaxHeapFreeRatio used
1068 // to resize the Java heap by some GC's. New flags can be implemented
1069 // if really needed. MinHeapFreeRatio is used to calculate how much
1070 // free space is desirable in the metaspace capacity to decide how much
1071 // to increase the HWM. MaxHeapFreeRatio is used to decide how much
1072 // free space is desirable in the metaspace capacity before decreasing
1073 // the HWM.
1075 // Calculate the amount to increase the high water mark (HWM).
1076 // Increase by a minimum amount (MinMetaspaceExpansion) so that
1077 // another expansion is not requested too soon. If that is not
1078 // enough to satisfy the allocation (i.e. big enough for a word_size
1079 // allocation), increase by MaxMetaspaceExpansion. If that is still
1080 // not enough, expand by the size of the allocation (word_size) plus
1081 // some.
1082 size_t MetaspaceGC::delta_capacity_until_GC(size_t word_size) {
1083 size_t before_inc = MetaspaceGC::capacity_until_GC();
1084 size_t min_delta_words = MinMetaspaceExpansion / BytesPerWord;
1085 size_t max_delta_words = MaxMetaspaceExpansion / BytesPerWord;
1086 size_t page_size_words = os::vm_page_size() / BytesPerWord;
1087 size_t size_delta_words = align_size_up(word_size, page_size_words);
1088 size_t delta_words = MAX2(size_delta_words, min_delta_words);
1089 if (delta_words > min_delta_words) {
1090 // Don't want to hit the high water mark on the next
1091 // allocation so make the delta greater than just enough
1092 // for this allocation.
1093 delta_words = MAX2(delta_words, max_delta_words);
1094 if (delta_words > max_delta_words) {
1095 // This allocation is large but the next ones are probably not
1096 // so increase by the minimum.
1097 delta_words = delta_words + min_delta_words;
1098 }
1099 }
1100 return delta_words;
1101 }
1103 bool MetaspaceGC::should_expand(VirtualSpaceList* vsl, size_t word_size) {
1105 // Class virtual space should always be expanded. Call GC for the other
1106 // metadata virtual space.
1107 if (vsl == Metaspace::class_space_list()) return true;
1109 // If the user wants a limit, impose one.
1110 size_t max_metaspace_size_words = MaxMetaspaceSize / BytesPerWord;
1111 size_t metaspace_size_words = MetaspaceSize / BytesPerWord;
1112 if (!FLAG_IS_DEFAULT(MaxMetaspaceSize) &&
1113 vsl->capacity_words_sum() >= max_metaspace_size_words) {
1114 return false;
1115 }
1117 // If this is part of an allocation after a GC, expand
1118 // unconditionally.
1119 if(MetaspaceGC::expand_after_GC()) {
1120 return true;
1121 }
1123 // If the capacity is below the minimum capacity, allow the
1124 // expansion. Also set the high-water-mark (capacity_until_GC)
1125 // to that minimum capacity so that a GC will not be induced
1126 // until that minimum capacity is exceeded.
1127 if (vsl->capacity_words_sum() < metaspace_size_words ||
1128 capacity_until_GC() == 0) {
1129 set_capacity_until_GC(metaspace_size_words);
1130 return true;
1131 } else {
1132 if (vsl->capacity_words_sum() < capacity_until_GC()) {
1133 return true;
1134 } else {
1135 if (TraceMetadataChunkAllocation && Verbose) {
1136 gclog_or_tty->print_cr(" allocation request size " SIZE_FORMAT
1137 " capacity_until_GC " SIZE_FORMAT
1138 " capacity_words_sum " SIZE_FORMAT
1139 " used_words_sum " SIZE_FORMAT
1140 " free chunks " SIZE_FORMAT
1141 " free chunks count %d",
1142 word_size,
1143 capacity_until_GC(),
1144 vsl->capacity_words_sum(),
1145 vsl->used_words_sum(),
1146 vsl->chunk_manager()->free_chunks_total(),
1147 vsl->chunk_manager()->free_chunks_count());
1148 }
1149 return false;
1150 }
1151 }
1152 }
1154 // Variables are in bytes
1156 void MetaspaceGC::compute_new_size() {
1157 assert(_shrink_factor <= 100, "invalid shrink factor");
1158 uint current_shrink_factor = _shrink_factor;
1159 _shrink_factor = 0;
1161 VirtualSpaceList *vsl = Metaspace::space_list();
1163 size_t capacity_after_gc = vsl->capacity_bytes_sum();
1164 // Check to see if these two can be calculated without walking the CLDG
1165 size_t used_after_gc = vsl->used_bytes_sum();
1166 size_t capacity_until_GC = vsl->capacity_bytes_sum();
1167 size_t free_after_gc = capacity_until_GC - used_after_gc;
1169 const double minimum_free_percentage = MinHeapFreeRatio / 100.0;
1170 const double maximum_used_percentage = 1.0 - minimum_free_percentage;
1172 const double min_tmp = used_after_gc / maximum_used_percentage;
1173 size_t minimum_desired_capacity =
1174 (size_t)MIN2(min_tmp, double(max_uintx));
1175 // Don't shrink less than the initial generation size
1176 minimum_desired_capacity = MAX2(minimum_desired_capacity,
1177 MetaspaceSize);
1179 if (PrintGCDetails && Verbose) {
1180 const double free_percentage = ((double)free_after_gc) / capacity_until_GC;
1181 gclog_or_tty->print_cr("\nMetaspaceGC::compute_new_size: ");
1182 gclog_or_tty->print_cr(" "
1183 " minimum_free_percentage: %6.2f"
1184 " maximum_used_percentage: %6.2f",
1185 minimum_free_percentage,
1186 maximum_used_percentage);
1187 double d_free_after_gc = free_after_gc / (double) K;
1188 gclog_or_tty->print_cr(" "
1189 " free_after_gc : %6.1fK"
1190 " used_after_gc : %6.1fK"
1191 " capacity_after_gc : %6.1fK"
1192 " metaspace HWM : %6.1fK",
1193 free_after_gc / (double) K,
1194 used_after_gc / (double) K,
1195 capacity_after_gc / (double) K,
1196 capacity_until_GC / (double) K);
1197 gclog_or_tty->print_cr(" "
1198 " free_percentage: %6.2f",
1199 free_percentage);
1200 }
1203 if (capacity_until_GC < minimum_desired_capacity) {
1204 // If we have less capacity below the metaspace HWM, then
1205 // increment the HWM.
1206 size_t expand_bytes = minimum_desired_capacity - capacity_until_GC;
1207 // Don't expand unless it's significant
1208 if (expand_bytes >= MinMetaspaceExpansion) {
1209 size_t expand_words = expand_bytes / BytesPerWord;
1210 MetaspaceGC::inc_capacity_until_GC(expand_words);
1211 }
1212 if (PrintGCDetails && Verbose) {
1213 size_t new_capacity_until_GC = MetaspaceGC::capacity_until_GC_in_bytes();
1214 gclog_or_tty->print_cr(" expanding:"
1215 " minimum_desired_capacity: %6.1fK"
1216 " expand_words: %6.1fK"
1217 " MinMetaspaceExpansion: %6.1fK"
1218 " new metaspace HWM: %6.1fK",
1219 minimum_desired_capacity / (double) K,
1220 expand_bytes / (double) K,
1221 MinMetaspaceExpansion / (double) K,
1222 new_capacity_until_GC / (double) K);
1223 }
1224 return;
1225 }
1227 // No expansion, now see if we want to shrink
1228 size_t shrink_words = 0;
1229 // We would never want to shrink more than this
1230 size_t max_shrink_words = capacity_until_GC - minimum_desired_capacity;
1231 assert(max_shrink_words >= 0, err_msg("max_shrink_words " SIZE_FORMAT,
1232 max_shrink_words));
1234 // Should shrinking be considered?
1235 if (MaxHeapFreeRatio < 100) {
1236 const double maximum_free_percentage = MaxHeapFreeRatio / 100.0;
1237 const double minimum_used_percentage = 1.0 - maximum_free_percentage;
1238 const double max_tmp = used_after_gc / minimum_used_percentage;
1239 size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx));
1240 maximum_desired_capacity = MAX2(maximum_desired_capacity,
1241 MetaspaceSize);
1242 if (PrintGC && Verbose) {
1243 gclog_or_tty->print_cr(" "
1244 " maximum_free_percentage: %6.2f"
1245 " minimum_used_percentage: %6.2f",
1246 maximum_free_percentage,
1247 minimum_used_percentage);
1248 gclog_or_tty->print_cr(" "
1249 " capacity_until_GC: %6.1fK"
1250 " minimum_desired_capacity: %6.1fK"
1251 " maximum_desired_capacity: %6.1fK",
1252 capacity_until_GC / (double) K,
1253 minimum_desired_capacity / (double) K,
1254 maximum_desired_capacity / (double) K);
1255 }
1257 assert(minimum_desired_capacity <= maximum_desired_capacity,
1258 "sanity check");
1260 if (capacity_until_GC > maximum_desired_capacity) {
1261 // Capacity too large, compute shrinking size
1262 shrink_words = capacity_until_GC - maximum_desired_capacity;
1263 // We don't want shrink all the way back to initSize if people call
1264 // System.gc(), because some programs do that between "phases" and then
1265 // we'd just have to grow the heap up again for the next phase. So we
1266 // damp the shrinking: 0% on the first call, 10% on the second call, 40%
1267 // on the third call, and 100% by the fourth call. But if we recompute
1268 // size without shrinking, it goes back to 0%.
1269 shrink_words = shrink_words / 100 * current_shrink_factor;
1270 assert(shrink_words <= max_shrink_words,
1271 err_msg("invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT,
1272 shrink_words, max_shrink_words));
1273 if (current_shrink_factor == 0) {
1274 _shrink_factor = 10;
1275 } else {
1276 _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100);
1277 }
1278 if (PrintGCDetails && Verbose) {
1279 gclog_or_tty->print_cr(" "
1280 " shrinking:"
1281 " initSize: %.1fK"
1282 " maximum_desired_capacity: %.1fK",
1283 MetaspaceSize / (double) K,
1284 maximum_desired_capacity / (double) K);
1285 gclog_or_tty->print_cr(" "
1286 " shrink_words: %.1fK"
1287 " current_shrink_factor: %d"
1288 " new shrink factor: %d"
1289 " MinMetaspaceExpansion: %.1fK",
1290 shrink_words / (double) K,
1291 current_shrink_factor,
1292 _shrink_factor,
1293 MinMetaspaceExpansion / (double) K);
1294 }
1295 }
1296 }
1299 // Don't shrink unless it's significant
1300 if (shrink_words >= MinMetaspaceExpansion) {
1301 VirtualSpaceNode* csp = vsl->current_virtual_space();
1302 size_t available_to_shrink = csp->capacity_words_in_vs() -
1303 csp->used_words_in_vs();
1304 shrink_words = MIN2(shrink_words, available_to_shrink);
1305 csp->shrink_by(shrink_words);
1306 MetaspaceGC::dec_capacity_until_GC(shrink_words);
1307 if (PrintGCDetails && Verbose) {
1308 size_t new_capacity_until_GC = MetaspaceGC::capacity_until_GC_in_bytes();
1309 gclog_or_tty->print_cr(" metaspace HWM: %.1fK", new_capacity_until_GC / (double) K);
1310 }
1311 }
1312 assert(vsl->used_bytes_sum() == used_after_gc &&
1313 used_after_gc <= vsl->capacity_bytes_sum(),
1314 "sanity check");
1316 }
1318 // Metadebug methods
1320 void Metadebug::deallocate_chunk_a_lot(SpaceManager* sm,
1321 size_t chunk_word_size){
1322 #ifdef ASSERT
1323 VirtualSpaceList* vsl = sm->vs_list();
1324 if (MetaDataDeallocateALot &&
1325 Metadebug::deallocate_chunk_a_lot_count() % MetaDataDeallocateALotInterval == 0 ) {
1326 Metadebug::reset_deallocate_chunk_a_lot_count();
1327 for (uint i = 0; i < metadata_deallocate_a_lock_chunk; i++) {
1328 Metachunk* dummy_chunk = vsl->current_virtual_space()->take_from_committed(chunk_word_size);
1329 if (dummy_chunk == NULL) {
1330 break;
1331 }
1332 vsl->chunk_manager()->chunk_freelist_deallocate(dummy_chunk);
1334 if (TraceMetadataChunkAllocation && Verbose) {
1335 gclog_or_tty->print("Metadebug::deallocate_chunk_a_lot: %d) ",
1336 sm->sum_count_in_chunks_in_use());
1337 dummy_chunk->print_on(gclog_or_tty);
1338 gclog_or_tty->print_cr(" Free chunks total %d count %d",
1339 vsl->chunk_manager()->free_chunks_total(),
1340 vsl->chunk_manager()->free_chunks_count());
1341 }
1342 }
1343 } else {
1344 Metadebug::inc_deallocate_chunk_a_lot_count();
1345 }
1346 #endif
1347 }
1349 void Metadebug::deallocate_block_a_lot(SpaceManager* sm,
1350 size_t raw_word_size){
1351 #ifdef ASSERT
1352 if (MetaDataDeallocateALot &&
1353 Metadebug::deallocate_block_a_lot_count() % MetaDataDeallocateALotInterval == 0 ) {
1354 Metadebug::set_deallocate_block_a_lot_count(0);
1355 for (uint i = 0; i < metadata_deallocate_a_lot_block; i++) {
1356 MetaWord* dummy_block = sm->allocate_work(raw_word_size);
1357 if (dummy_block == 0) {
1358 break;
1359 }
1360 sm->deallocate(dummy_block, raw_word_size);
1361 }
1362 } else {
1363 Metadebug::inc_deallocate_block_a_lot_count();
1364 }
1365 #endif
1366 }
1368 void Metadebug::init_allocation_fail_alot_count() {
1369 if (MetadataAllocationFailALot) {
1370 _allocation_fail_alot_count =
1371 1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0));
1372 }
1373 }
1375 #ifdef ASSERT
1376 bool Metadebug::test_metadata_failure() {
1377 if (MetadataAllocationFailALot &&
1378 Threads::is_vm_complete()) {
1379 if (_allocation_fail_alot_count > 0) {
1380 _allocation_fail_alot_count--;
1381 } else {
1382 if (TraceMetadataChunkAllocation && Verbose) {
1383 gclog_or_tty->print_cr("Metadata allocation failing for "
1384 "MetadataAllocationFailALot");
1385 }
1386 init_allocation_fail_alot_count();
1387 return true;
1388 }
1389 }
1390 return false;
1391 }
1392 #endif
1394 // ChunkList methods
1396 size_t ChunkList::sum_list_size() {
1397 size_t result = 0;
1398 Metachunk* cur = head();
1399 while (cur != NULL) {
1400 result += cur->word_size();
1401 cur = cur->next();
1402 }
1403 return result;
1404 }
1406 size_t ChunkList::sum_list_count() {
1407 size_t result = 0;
1408 Metachunk* cur = head();
1409 while (cur != NULL) {
1410 result++;
1411 cur = cur->next();
1412 }
1413 return result;
1414 }
1416 size_t ChunkList::sum_list_capacity() {
1417 size_t result = 0;
1418 Metachunk* cur = head();
1419 while (cur != NULL) {
1420 result += cur->capacity_word_size();
1421 cur = cur->next();
1422 }
1423 return result;
1424 }
1426 void ChunkList::add_at_head(Metachunk* head, Metachunk* tail) {
1427 assert_lock_strong(SpaceManager::expand_lock());
1428 assert(head == tail || tail->next() == NULL,
1429 "Not the tail or the head has already been added to a list");
1431 if (TraceMetadataChunkAllocation && Verbose) {
1432 gclog_or_tty->print("ChunkList::add_at_head(head, tail): ");
1433 Metachunk* cur = head;
1434 while (cur != NULL) {
1435 gclog_or_tty->print(PTR_FORMAT " (" SIZE_FORMAT ") ", cur, cur->word_size());
1436 cur = cur->next();
1437 }
1438 gclog_or_tty->print_cr("");
1439 }
1441 if (tail != NULL) {
1442 tail->set_next(_head);
1443 }
1444 set_head(head);
1445 }
1447 void ChunkList::add_at_head(Metachunk* list) {
1448 if (list == NULL) {
1449 // Nothing to add
1450 return;
1451 }
1452 assert_lock_strong(SpaceManager::expand_lock());
1453 Metachunk* head = list;
1454 Metachunk* tail = list;
1455 Metachunk* cur = head->next();
1456 // Search for the tail since it is not passed.
1457 while (cur != NULL) {
1458 tail = cur;
1459 cur = cur->next();
1460 }
1461 add_at_head(head, tail);
1462 }
1464 // ChunkManager methods
1466 // Verification of _free_chunks_total and _free_chunks_count does not
1467 // work with the CMS collector because its use of additional locks
1468 // complicate the mutex deadlock detection but it can still be useful
1469 // for detecting errors in the chunk accounting with other collectors.
1471 size_t ChunkManager::free_chunks_total() {
1472 #ifdef ASSERT
1473 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
1474 MutexLockerEx cl(SpaceManager::expand_lock(),
1475 Mutex::_no_safepoint_check_flag);
1476 slow_locked_verify_free_chunks_total();
1477 }
1478 #endif
1479 return _free_chunks_total;
1480 }
1482 size_t ChunkManager::free_chunks_total_in_bytes() {
1483 return free_chunks_total() * BytesPerWord;
1484 }
1486 size_t ChunkManager::free_chunks_count() {
1487 #ifdef ASSERT
1488 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) {
1489 MutexLockerEx cl(SpaceManager::expand_lock(),
1490 Mutex::_no_safepoint_check_flag);
1491 // This lock is only needed in debug because the verification
1492 // of the _free_chunks_totals walks the list of free chunks
1493 slow_locked_verify_free_chunks_count();
1494 }
1495 #endif
1496 return _free_chunks_count;
1497 }
1499 void ChunkManager::locked_verify_free_chunks_total() {
1500 assert_lock_strong(SpaceManager::expand_lock());
1501 assert(sum_free_chunks() == _free_chunks_total,
1502 err_msg("_free_chunks_total " SIZE_FORMAT " is not the"
1503 " same as sum " SIZE_FORMAT, _free_chunks_total,
1504 sum_free_chunks()));
1505 }
1507 void ChunkManager::verify_free_chunks_total() {
1508 MutexLockerEx cl(SpaceManager::expand_lock(),
1509 Mutex::_no_safepoint_check_flag);
1510 locked_verify_free_chunks_total();
1511 }
1513 void ChunkManager::locked_verify_free_chunks_count() {
1514 assert_lock_strong(SpaceManager::expand_lock());
1515 assert(sum_free_chunks_count() == _free_chunks_count,
1516 err_msg("_free_chunks_count " SIZE_FORMAT " is not the"
1517 " same as sum " SIZE_FORMAT, _free_chunks_count,
1518 sum_free_chunks_count()));
1519 }
1521 void ChunkManager::verify_free_chunks_count() {
1522 #ifdef ASSERT
1523 MutexLockerEx cl(SpaceManager::expand_lock(),
1524 Mutex::_no_safepoint_check_flag);
1525 locked_verify_free_chunks_count();
1526 #endif
1527 }
1529 void ChunkManager::verify() {
1530 MutexLockerEx cl(SpaceManager::expand_lock(),
1531 Mutex::_no_safepoint_check_flag);
1532 locked_verify();
1533 }
1535 void ChunkManager::locked_verify() {
1536 locked_verify_free_chunks_count();
1537 locked_verify_free_chunks_total();
1538 }
1540 void ChunkManager::locked_print_free_chunks(outputStream* st) {
1541 assert_lock_strong(SpaceManager::expand_lock());
1542 st->print_cr("Free chunk total " SIZE_FORMAT " count " SIZE_FORMAT,
1543 _free_chunks_total, _free_chunks_count);
1544 }
1546 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) {
1547 assert_lock_strong(SpaceManager::expand_lock());
1548 st->print_cr("Sum free chunk total " SIZE_FORMAT " count " SIZE_FORMAT,
1549 sum_free_chunks(), sum_free_chunks_count());
1550 }
1551 ChunkList* ChunkManager::free_chunks(ChunkIndex index) {
1552 return &_free_chunks[index];
1553 }
1555 // These methods that sum the free chunk lists are used in printing
1556 // methods that are used in product builds.
1557 size_t ChunkManager::sum_free_chunks() {
1558 assert_lock_strong(SpaceManager::expand_lock());
1559 size_t result = 0;
1560 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1561 ChunkList* list = free_chunks(i);
1563 if (list == NULL) {
1564 continue;
1565 }
1567 result = result + list->sum_list_capacity();
1568 }
1569 result = result + humongous_dictionary()->total_size();
1570 return result;
1571 }
1573 size_t ChunkManager::sum_free_chunks_count() {
1574 assert_lock_strong(SpaceManager::expand_lock());
1575 size_t count = 0;
1576 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) {
1577 ChunkList* list = free_chunks(i);
1578 if (list == NULL) {
1579 continue;
1580 }
1581 count = count + list->sum_list_count();
1582 }
1583 count = count + humongous_dictionary()->total_free_blocks();
1584 return count;
1585 }
1587 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) {
1588 ChunkIndex index = list_index(word_size);
1589 assert(index < HumongousIndex, "No humongous list");
1590 return free_chunks(index);
1591 }
1593 void ChunkManager::free_chunks_put(Metachunk* chunk) {
1594 assert_lock_strong(SpaceManager::expand_lock());
1595 ChunkList* free_list = find_free_chunks_list(chunk->word_size());
1596 chunk->set_next(free_list->head());
1597 free_list->set_head(chunk);
1598 // chunk is being returned to the chunk free list
1599 inc_free_chunks_total(chunk->capacity_word_size());
1600 slow_locked_verify();
1601 }
1603 void ChunkManager::chunk_freelist_deallocate(Metachunk* chunk) {
1604 // The deallocation of a chunk originates in the freelist
1605 // manangement code for a Metaspace and does not hold the
1606 // lock.
1607 assert(chunk != NULL, "Deallocating NULL");
1608 assert_lock_strong(SpaceManager::expand_lock());
1609 slow_locked_verify();
1610 if (TraceMetadataChunkAllocation) {
1611 tty->print_cr("ChunkManager::chunk_freelist_deallocate: chunk "
1612 PTR_FORMAT " size " SIZE_FORMAT,
1613 chunk, chunk->word_size());
1614 }
1615 free_chunks_put(chunk);
1616 }
1618 Metachunk* ChunkManager::free_chunks_get(size_t word_size) {
1619 assert_lock_strong(SpaceManager::expand_lock());
1621 slow_locked_verify();
1623 Metachunk* chunk = NULL;
1624 if (list_index(word_size) != HumongousIndex) {
1625 ChunkList* free_list = find_free_chunks_list(word_size);
1626 assert(free_list != NULL, "Sanity check");
1628 chunk = free_list->head();
1629 debug_only(Metachunk* debug_head = chunk;)
1631 if (chunk == NULL) {
1632 return NULL;
1633 }
1635 // Remove the chunk as the head of the list.
1636 free_list->set_head(chunk->next());
1638 // Chunk is being removed from the chunks free list.
1639 dec_free_chunks_total(chunk->capacity_word_size());
1641 if (TraceMetadataChunkAllocation && Verbose) {
1642 tty->print_cr("ChunkManager::free_chunks_get: free_list "
1643 PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT,
1644 free_list, chunk, chunk->word_size());
1645 }
1646 } else {
1647 chunk = humongous_dictionary()->get_chunk(
1648 word_size,
1649 FreeBlockDictionary<Metachunk>::atLeast);
1651 if (chunk != NULL) {
1652 if (TraceMetadataHumongousAllocation) {
1653 size_t waste = chunk->word_size() - word_size;
1654 tty->print_cr("Free list allocate humongous chunk size " SIZE_FORMAT
1655 " for requested size " SIZE_FORMAT
1656 " waste " SIZE_FORMAT,
1657 chunk->word_size(), word_size, waste);
1658 }
1659 // Chunk is being removed from the chunks free list.
1660 dec_free_chunks_total(chunk->capacity_word_size());
1661 #ifdef ASSERT
1662 chunk->set_is_free(false);
1663 #endif
1664 } else {
1665 return NULL;
1666 }
1667 }
1669 // Remove it from the links to this freelist
1670 chunk->set_next(NULL);
1671 chunk->set_prev(NULL);
1672 slow_locked_verify();
1673 return chunk;
1674 }
1676 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) {
1677 assert_lock_strong(SpaceManager::expand_lock());
1678 slow_locked_verify();
1680 // Take from the beginning of the list
1681 Metachunk* chunk = free_chunks_get(word_size);
1682 if (chunk == NULL) {
1683 return NULL;
1684 }
1686 assert((word_size <= chunk->word_size()) ||
1687 list_index(chunk->word_size() == HumongousIndex),
1688 "Non-humongous variable sized chunk");
1689 if (TraceMetadataChunkAllocation) {
1690 size_t list_count;
1691 if (list_index(word_size) < HumongousIndex) {
1692 ChunkList* list = find_free_chunks_list(word_size);
1693 list_count = list->sum_list_count();
1694 } else {
1695 list_count = humongous_dictionary()->total_count();
1696 }
1697 tty->print("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk "
1698 PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ",
1699 this, chunk, chunk->word_size(), list_count);
1700 locked_print_free_chunks(tty);
1701 }
1703 return chunk;
1704 }
1706 void ChunkManager::print_on(outputStream* out) {
1707 if (PrintFLSStatistics != 0) {
1708 humongous_dictionary()->report_statistics();
1709 }
1710 }
1712 // SpaceManager methods
1714 void SpaceManager::get_initial_chunk_sizes(Metaspace::MetaspaceType type,
1715 size_t* chunk_word_size,
1716 size_t* class_chunk_word_size) {
1717 switch (type) {
1718 case Metaspace::BootMetaspaceType:
1719 *chunk_word_size = Metaspace::first_chunk_word_size();
1720 *class_chunk_word_size = Metaspace::first_class_chunk_word_size();
1721 break;
1722 case Metaspace::ROMetaspaceType:
1723 *chunk_word_size = SharedReadOnlySize / wordSize;
1724 *class_chunk_word_size = ClassSpecializedChunk;
1725 break;
1726 case Metaspace::ReadWriteMetaspaceType:
1727 *chunk_word_size = SharedReadWriteSize / wordSize;
1728 *class_chunk_word_size = ClassSpecializedChunk;
1729 break;
1730 case Metaspace::AnonymousMetaspaceType:
1731 case Metaspace::ReflectionMetaspaceType:
1732 *chunk_word_size = SpecializedChunk;
1733 *class_chunk_word_size = ClassSpecializedChunk;
1734 break;
1735 default:
1736 *chunk_word_size = SmallChunk;
1737 *class_chunk_word_size = ClassSmallChunk;
1738 break;
1739 }
1740 assert(chunk_word_size != 0 && class_chunk_word_size != 0,
1741 err_msg("Initial chunks sizes bad: data " SIZE_FORMAT
1742 " class " SIZE_FORMAT,
1743 chunk_word_size, class_chunk_word_size));
1744 }
1746 size_t SpaceManager::sum_free_in_chunks_in_use() const {
1747 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1748 size_t free = 0;
1749 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1750 Metachunk* chunk = chunks_in_use(i);
1751 while (chunk != NULL) {
1752 free += chunk->free_word_size();
1753 chunk = chunk->next();
1754 }
1755 }
1756 return free;
1757 }
1759 size_t SpaceManager::sum_waste_in_chunks_in_use() const {
1760 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1761 size_t result = 0;
1762 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1763 result += sum_waste_in_chunks_in_use(i);
1764 }
1766 return result;
1767 }
1769 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const {
1770 size_t result = 0;
1771 Metachunk* chunk = chunks_in_use(index);
1772 // Count the free space in all the chunk but not the
1773 // current chunk from which allocations are still being done.
1774 if (chunk != NULL) {
1775 Metachunk* prev = chunk;
1776 while (chunk != NULL && chunk != current_chunk()) {
1777 result += chunk->free_word_size();
1778 prev = chunk;
1779 chunk = chunk->next();
1780 }
1781 }
1782 return result;
1783 }
1785 size_t SpaceManager::sum_capacity_in_chunks_in_use() const {
1786 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1787 size_t sum = 0;
1788 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1789 Metachunk* chunk = chunks_in_use(i);
1790 while (chunk != NULL) {
1791 // Just changed this sum += chunk->capacity_word_size();
1792 // sum += chunk->word_size() - Metachunk::overhead();
1793 sum += chunk->capacity_word_size();
1794 chunk = chunk->next();
1795 }
1796 }
1797 return sum;
1798 }
1800 size_t SpaceManager::sum_count_in_chunks_in_use() {
1801 size_t count = 0;
1802 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1803 count = count + sum_count_in_chunks_in_use(i);
1804 }
1806 return count;
1807 }
1809 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) {
1810 size_t count = 0;
1811 Metachunk* chunk = chunks_in_use(i);
1812 while (chunk != NULL) {
1813 count++;
1814 chunk = chunk->next();
1815 }
1816 return count;
1817 }
1820 size_t SpaceManager::sum_used_in_chunks_in_use() const {
1821 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
1822 size_t used = 0;
1823 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1824 Metachunk* chunk = chunks_in_use(i);
1825 while (chunk != NULL) {
1826 used += chunk->used_word_size();
1827 chunk = chunk->next();
1828 }
1829 }
1830 return used;
1831 }
1833 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const {
1835 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1836 Metachunk* chunk = chunks_in_use(i);
1837 st->print("SpaceManager: %s " PTR_FORMAT,
1838 chunk_size_name(i), chunk);
1839 if (chunk != NULL) {
1840 st->print_cr(" free " SIZE_FORMAT,
1841 chunk->free_word_size());
1842 } else {
1843 st->print_cr("");
1844 }
1845 }
1847 vs_list()->chunk_manager()->locked_print_free_chunks(st);
1848 vs_list()->chunk_manager()->locked_print_sum_free_chunks(st);
1849 }
1851 size_t SpaceManager::calc_chunk_size(size_t word_size) {
1853 // Decide between a small chunk and a medium chunk. Up to
1854 // _small_chunk_limit small chunks can be allocated but
1855 // once a medium chunk has been allocated, no more small
1856 // chunks will be allocated.
1857 size_t chunk_word_size;
1858 if (chunks_in_use(MediumIndex) == NULL &&
1859 (!has_small_chunk_limit() ||
1860 sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit)) {
1861 chunk_word_size = (size_t) small_chunk_size();
1862 if (word_size + Metachunk::overhead() > small_chunk_size()) {
1863 chunk_word_size = medium_chunk_size();
1864 }
1865 } else {
1866 chunk_word_size = medium_chunk_size();
1867 }
1869 // Might still need a humongous chunk. Enforce an
1870 // eight word granularity to facilitate reuse (some
1871 // wastage but better chance of reuse).
1872 size_t if_humongous_sized_chunk =
1873 align_size_up(word_size + Metachunk::overhead(),
1874 HumongousChunkGranularity);
1875 chunk_word_size =
1876 MAX2((size_t) chunk_word_size, if_humongous_sized_chunk);
1878 assert(!SpaceManager::is_humongous(word_size) ||
1879 chunk_word_size == if_humongous_sized_chunk,
1880 err_msg("Size calculation is wrong, word_size " SIZE_FORMAT
1881 " chunk_word_size " SIZE_FORMAT,
1882 word_size, chunk_word_size));
1883 if (TraceMetadataHumongousAllocation &&
1884 SpaceManager::is_humongous(word_size)) {
1885 gclog_or_tty->print_cr("Metadata humongous allocation:");
1886 gclog_or_tty->print_cr(" word_size " PTR_FORMAT, word_size);
1887 gclog_or_tty->print_cr(" chunk_word_size " PTR_FORMAT,
1888 chunk_word_size);
1889 gclog_or_tty->print_cr(" chunk overhead " PTR_FORMAT,
1890 Metachunk::overhead());
1891 }
1892 return chunk_word_size;
1893 }
1895 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) {
1896 assert(vs_list()->current_virtual_space() != NULL,
1897 "Should have been set");
1898 assert(current_chunk() == NULL ||
1899 current_chunk()->allocate(word_size) == NULL,
1900 "Don't need to expand");
1901 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
1903 if (TraceMetadataChunkAllocation && Verbose) {
1904 size_t words_left = 0;
1905 size_t words_used = 0;
1906 if (current_chunk() != NULL) {
1907 words_left = current_chunk()->free_word_size();
1908 words_used = current_chunk()->used_word_size();
1909 }
1910 gclog_or_tty->print_cr("SpaceManager::grow_and_allocate for " SIZE_FORMAT
1911 " words " SIZE_FORMAT " words used " SIZE_FORMAT
1912 " words left",
1913 word_size, words_used, words_left);
1914 }
1916 // Get another chunk out of the virtual space
1917 size_t grow_chunks_by_words = calc_chunk_size(word_size);
1918 Metachunk* next = get_new_chunk(word_size, grow_chunks_by_words);
1920 // If a chunk was available, add it to the in-use chunk list
1921 // and do an allocation from it.
1922 if (next != NULL) {
1923 Metadebug::deallocate_chunk_a_lot(this, grow_chunks_by_words);
1924 // Add to this manager's list of chunks in use.
1925 add_chunk(next, false);
1926 return next->allocate(word_size);
1927 }
1928 return NULL;
1929 }
1931 void SpaceManager::print_on(outputStream* st) const {
1933 for (ChunkIndex i = ZeroIndex;
1934 i < NumberOfInUseLists ;
1935 i = next_chunk_index(i) ) {
1936 st->print_cr(" chunks_in_use " PTR_FORMAT " chunk size " PTR_FORMAT,
1937 chunks_in_use(i),
1938 chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size());
1939 }
1940 st->print_cr(" waste: Small " SIZE_FORMAT " Medium " SIZE_FORMAT
1941 " Humongous " SIZE_FORMAT,
1942 sum_waste_in_chunks_in_use(SmallIndex),
1943 sum_waste_in_chunks_in_use(MediumIndex),
1944 sum_waste_in_chunks_in_use(HumongousIndex));
1945 // block free lists
1946 if (block_freelists() != NULL) {
1947 st->print_cr("total in block free lists " SIZE_FORMAT,
1948 block_freelists()->total_size());
1949 }
1950 }
1952 SpaceManager::SpaceManager(Mutex* lock,
1953 VirtualSpaceList* vs_list) :
1954 _vs_list(vs_list),
1955 _allocation_total(0),
1956 _lock(lock)
1957 {
1958 initialize();
1959 }
1961 void SpaceManager::initialize() {
1962 Metadebug::init_allocation_fail_alot_count();
1963 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
1964 _chunks_in_use[i] = NULL;
1965 }
1966 _current_chunk = NULL;
1967 if (TraceMetadataChunkAllocation && Verbose) {
1968 gclog_or_tty->print_cr("SpaceManager(): " PTR_FORMAT, this);
1969 }
1970 }
1972 SpaceManager::~SpaceManager() {
1973 MutexLockerEx fcl(SpaceManager::expand_lock(),
1974 Mutex::_no_safepoint_check_flag);
1976 ChunkManager* chunk_manager = vs_list()->chunk_manager();
1978 chunk_manager->slow_locked_verify();
1980 if (TraceMetadataChunkAllocation && Verbose) {
1981 gclog_or_tty->print_cr("~SpaceManager(): " PTR_FORMAT, this);
1982 locked_print_chunks_in_use_on(gclog_or_tty);
1983 }
1985 // Mangle freed memory.
1986 NOT_PRODUCT(mangle_freed_chunks();)
1988 // Have to update before the chunks_in_use lists are emptied
1989 // below.
1990 chunk_manager->inc_free_chunks_total(sum_capacity_in_chunks_in_use(),
1991 sum_count_in_chunks_in_use());
1993 // Add all the chunks in use by this space manager
1994 // to the global list of free chunks.
1996 // Follow each list of chunks-in-use and add them to the
1997 // free lists. Each list is NULL terminated.
1999 for (ChunkIndex i = ZeroIndex; i < HumongousIndex; i = next_chunk_index(i)) {
2000 if (TraceMetadataChunkAllocation && Verbose) {
2001 gclog_or_tty->print_cr("returned %d %s chunks to freelist",
2002 sum_count_in_chunks_in_use(i),
2003 chunk_size_name(i));
2004 }
2005 Metachunk* chunks = chunks_in_use(i);
2006 chunk_manager->free_chunks(i)->add_at_head(chunks);
2007 set_chunks_in_use(i, NULL);
2008 if (TraceMetadataChunkAllocation && Verbose) {
2009 gclog_or_tty->print_cr("updated freelist count %d %s",
2010 chunk_manager->free_chunks(i)->sum_list_count(),
2011 chunk_size_name(i));
2012 }
2013 assert(i != HumongousIndex, "Humongous chunks are handled explicitly later");
2014 }
2016 // The medium chunk case may be optimized by passing the head and
2017 // tail of the medium chunk list to add_at_head(). The tail is often
2018 // the current chunk but there are probably exceptions.
2020 // Humongous chunks
2021 if (TraceMetadataChunkAllocation && Verbose) {
2022 gclog_or_tty->print_cr("returned %d %s humongous chunks to dictionary",
2023 sum_count_in_chunks_in_use(HumongousIndex),
2024 chunk_size_name(HumongousIndex));
2025 gclog_or_tty->print("Humongous chunk dictionary: ");
2026 }
2027 // Humongous chunks are never the current chunk.
2028 Metachunk* humongous_chunks = chunks_in_use(HumongousIndex);
2030 while (humongous_chunks != NULL) {
2031 #ifdef ASSERT
2032 humongous_chunks->set_is_free(true);
2033 #endif
2034 if (TraceMetadataChunkAllocation && Verbose) {
2035 gclog_or_tty->print(PTR_FORMAT " (" SIZE_FORMAT ") ",
2036 humongous_chunks,
2037 humongous_chunks->word_size());
2038 }
2039 assert(humongous_chunks->word_size() == (size_t)
2040 align_size_up(humongous_chunks->word_size(),
2041 HumongousChunkGranularity),
2042 err_msg("Humongous chunk size is wrong: word size " SIZE_FORMAT
2043 " granularity " SIZE_FORMAT,
2044 humongous_chunks->word_size(), HumongousChunkGranularity));
2045 Metachunk* next_humongous_chunks = humongous_chunks->next();
2046 chunk_manager->humongous_dictionary()->return_chunk(humongous_chunks);
2047 humongous_chunks = next_humongous_chunks;
2048 }
2049 if (TraceMetadataChunkAllocation && Verbose) {
2050 gclog_or_tty->print_cr("");
2051 gclog_or_tty->print_cr("updated dictionary count %d %s",
2052 chunk_manager->humongous_dictionary()->total_count(),
2053 chunk_size_name(HumongousIndex));
2054 }
2055 set_chunks_in_use(HumongousIndex, NULL);
2056 chunk_manager->slow_locked_verify();
2057 }
2059 const char* SpaceManager::chunk_size_name(ChunkIndex index) const {
2060 switch (index) {
2061 case SpecializedIndex:
2062 return "Specialized";
2063 case SmallIndex:
2064 return "Small";
2065 case MediumIndex:
2066 return "Medium";
2067 case HumongousIndex:
2068 return "Humongous";
2069 default:
2070 return NULL;
2071 }
2072 }
2074 ChunkIndex ChunkManager::list_index(size_t size) {
2075 switch (size) {
2076 case SpecializedChunk:
2077 assert(SpecializedChunk == ClassSpecializedChunk,
2078 "Need branch for ClassSpecializedChunk");
2079 return SpecializedIndex;
2080 case SmallChunk:
2081 case ClassSmallChunk:
2082 return SmallIndex;
2083 case MediumChunk:
2084 case ClassMediumChunk:
2085 return MediumIndex;
2086 default:
2087 assert(size > MediumChunk || size > ClassMediumChunk,
2088 "Not a humongous chunk");
2089 return HumongousIndex;
2090 }
2091 }
2093 void SpaceManager::deallocate(MetaWord* p, size_t word_size) {
2094 assert_lock_strong(_lock);
2095 size_t min_size = TreeChunk<Metablock, FreeList>::min_size();
2096 assert(word_size >= min_size,
2097 err_msg("Should not deallocate dark matter " SIZE_FORMAT, word_size));
2098 block_freelists()->return_block(p, word_size);
2099 }
2101 // Adds a chunk to the list of chunks in use.
2102 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) {
2104 assert(new_chunk != NULL, "Should not be NULL");
2105 assert(new_chunk->next() == NULL, "Should not be on a list");
2107 new_chunk->reset_empty();
2109 // Find the correct list and and set the current
2110 // chunk for that list.
2111 ChunkIndex index = ChunkManager::list_index(new_chunk->word_size());
2113 if (index != HumongousIndex) {
2114 set_current_chunk(new_chunk);
2115 new_chunk->set_next(chunks_in_use(index));
2116 set_chunks_in_use(index, new_chunk);
2117 } else {
2118 // For null class loader data and DumpSharedSpaces, the first chunk isn't
2119 // small, so small will be null. Link this first chunk as the current
2120 // chunk.
2121 if (make_current) {
2122 // Set as the current chunk but otherwise treat as a humongous chunk.
2123 set_current_chunk(new_chunk);
2124 }
2125 // Link at head. The _current_chunk only points to a humongous chunk for
2126 // the null class loader metaspace (class and data virtual space managers)
2127 // any humongous chunks so will not point to the tail
2128 // of the humongous chunks list.
2129 new_chunk->set_next(chunks_in_use(HumongousIndex));
2130 set_chunks_in_use(HumongousIndex, new_chunk);
2132 assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency");
2133 }
2135 assert(new_chunk->is_empty(), "Not ready for reuse");
2136 if (TraceMetadataChunkAllocation && Verbose) {
2137 gclog_or_tty->print("SpaceManager::add_chunk: %d) ",
2138 sum_count_in_chunks_in_use());
2139 new_chunk->print_on(gclog_or_tty);
2140 vs_list()->chunk_manager()->locked_print_free_chunks(tty);
2141 }
2142 }
2144 Metachunk* SpaceManager::get_new_chunk(size_t word_size,
2145 size_t grow_chunks_by_words) {
2147 Metachunk* next = vs_list()->get_new_chunk(word_size,
2148 grow_chunks_by_words,
2149 medium_chunk_bunch());
2151 if (TraceMetadataHumongousAllocation &&
2152 SpaceManager::is_humongous(next->word_size())) {
2153 gclog_or_tty->print_cr(" new humongous chunk word size " PTR_FORMAT,
2154 next->word_size());
2155 }
2157 return next;
2158 }
2160 MetaWord* SpaceManager::allocate(size_t word_size) {
2161 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2163 // If only the dictionary is going to be used (i.e., no
2164 // indexed free list), then there is a minimum size requirement.
2165 // MinChunkSize is a placeholder for the real minimum size JJJ
2166 size_t byte_size = word_size * BytesPerWord;
2168 size_t byte_size_with_overhead = byte_size + Metablock::overhead();
2170 size_t raw_bytes_size = MAX2(byte_size_with_overhead,
2171 Metablock::min_block_byte_size());
2172 raw_bytes_size = ARENA_ALIGN(raw_bytes_size);
2173 size_t raw_word_size = raw_bytes_size / BytesPerWord;
2174 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem");
2176 BlockFreelist* fl = block_freelists();
2177 MetaWord* p = NULL;
2178 // Allocation from the dictionary is expensive in the sense that
2179 // the dictionary has to be searched for a size. Don't allocate
2180 // from the dictionary until it starts to get fat. Is this
2181 // a reasonable policy? Maybe an skinny dictionary is fast enough
2182 // for allocations. Do some profiling. JJJ
2183 if (fl->total_size() > allocation_from_dictionary_limit) {
2184 p = fl->get_block(raw_word_size);
2185 }
2186 if (p == NULL) {
2187 p = allocate_work(raw_word_size);
2188 }
2189 Metadebug::deallocate_block_a_lot(this, raw_word_size);
2191 return p;
2192 }
2194 // Returns the address of spaced allocated for "word_size".
2195 // This methods does not know about blocks (Metablocks)
2196 MetaWord* SpaceManager::allocate_work(size_t word_size) {
2197 assert_lock_strong(_lock);
2198 #ifdef ASSERT
2199 if (Metadebug::test_metadata_failure()) {
2200 return NULL;
2201 }
2202 #endif
2203 // Is there space in the current chunk?
2204 MetaWord* result = NULL;
2206 // For DumpSharedSpaces, only allocate out of the current chunk which is
2207 // never null because we gave it the size we wanted. Caller reports out
2208 // of memory if this returns null.
2209 if (DumpSharedSpaces) {
2210 assert(current_chunk() != NULL, "should never happen");
2211 inc_allocation_total(word_size);
2212 return current_chunk()->allocate(word_size); // caller handles null result
2213 }
2214 if (current_chunk() != NULL) {
2215 result = current_chunk()->allocate(word_size);
2216 }
2218 if (result == NULL) {
2219 result = grow_and_allocate(word_size);
2220 }
2221 if (result > 0) {
2222 inc_allocation_total(word_size);
2223 assert(result != (MetaWord*) chunks_in_use(MediumIndex),
2224 "Head of the list is being allocated");
2225 }
2227 return result;
2228 }
2230 void SpaceManager::verify() {
2231 // If there are blocks in the dictionary, then
2232 // verfication of chunks does not work since
2233 // being in the dictionary alters a chunk.
2234 if (block_freelists()->total_size() == 0) {
2235 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
2236 Metachunk* curr = chunks_in_use(i);
2237 while (curr != NULL) {
2238 curr->verify();
2239 verify_chunk_size(curr);
2240 curr = curr->next();
2241 }
2242 }
2243 }
2244 }
2246 void SpaceManager::verify_chunk_size(Metachunk* chunk) {
2247 assert(is_humongous(chunk->word_size()) ||
2248 chunk->word_size() == medium_chunk_size() ||
2249 chunk->word_size() == small_chunk_size() ||
2250 chunk->word_size() == specialized_chunk_size(),
2251 "Chunk size is wrong");
2252 return;
2253 }
2255 #ifdef ASSERT
2256 void SpaceManager::verify_allocation_total() {
2257 // Verification is only guaranteed at a safepoint.
2258 if (SafepointSynchronize::is_at_safepoint()) {
2259 gclog_or_tty->print_cr("Chunk " PTR_FORMAT " allocation_total " SIZE_FORMAT
2260 " sum_used_in_chunks_in_use " SIZE_FORMAT,
2261 this,
2262 allocation_total(),
2263 sum_used_in_chunks_in_use());
2264 }
2265 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
2266 assert(allocation_total() == sum_used_in_chunks_in_use(),
2267 err_msg("allocation total is not consistent %d vs %d",
2268 allocation_total(), sum_used_in_chunks_in_use()));
2269 }
2271 #endif
2273 void SpaceManager::dump(outputStream* const out) const {
2274 size_t curr_total = 0;
2275 size_t waste = 0;
2276 uint i = 0;
2277 size_t used = 0;
2278 size_t capacity = 0;
2280 // Add up statistics for all chunks in this SpaceManager.
2281 for (ChunkIndex index = ZeroIndex;
2282 index < NumberOfInUseLists;
2283 index = next_chunk_index(index)) {
2284 for (Metachunk* curr = chunks_in_use(index);
2285 curr != NULL;
2286 curr = curr->next()) {
2287 out->print("%d) ", i++);
2288 curr->print_on(out);
2289 if (TraceMetadataChunkAllocation && Verbose) {
2290 block_freelists()->print_on(out);
2291 }
2292 curr_total += curr->word_size();
2293 used += curr->used_word_size();
2294 capacity += curr->capacity_word_size();
2295 waste += curr->free_word_size() + curr->overhead();;
2296 }
2297 }
2299 size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size();
2300 // Free space isn't wasted.
2301 waste -= free;
2303 out->print_cr("total of all chunks " SIZE_FORMAT " used " SIZE_FORMAT
2304 " free " SIZE_FORMAT " capacity " SIZE_FORMAT
2305 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste);
2306 }
2308 #ifndef PRODUCT
2309 void SpaceManager::mangle_freed_chunks() {
2310 for (ChunkIndex index = ZeroIndex;
2311 index < NumberOfInUseLists;
2312 index = next_chunk_index(index)) {
2313 for (Metachunk* curr = chunks_in_use(index);
2314 curr != NULL;
2315 curr = curr->next()) {
2316 curr->mangle();
2317 }
2318 }
2319 }
2320 #endif // PRODUCT
2322 // MetaspaceAux
2324 size_t MetaspaceAux::used_in_bytes(Metaspace::MetadataType mdtype) {
2325 size_t used = 0;
2326 ClassLoaderDataGraphMetaspaceIterator iter;
2327 while (iter.repeat()) {
2328 Metaspace* msp = iter.get_next();
2329 // Sum allocation_total for each metaspace
2330 if (msp != NULL) {
2331 used += msp->used_words(mdtype);
2332 }
2333 }
2334 return used * BytesPerWord;
2335 }
2337 size_t MetaspaceAux::free_in_bytes(Metaspace::MetadataType mdtype) {
2338 size_t free = 0;
2339 ClassLoaderDataGraphMetaspaceIterator iter;
2340 while (iter.repeat()) {
2341 Metaspace* msp = iter.get_next();
2342 if (msp != NULL) {
2343 free += msp->free_words(mdtype);
2344 }
2345 }
2346 return free * BytesPerWord;
2347 }
2349 size_t MetaspaceAux::capacity_in_bytes(Metaspace::MetadataType mdtype) {
2350 size_t capacity = free_chunks_total(mdtype);
2351 ClassLoaderDataGraphMetaspaceIterator iter;
2352 while (iter.repeat()) {
2353 Metaspace* msp = iter.get_next();
2354 if (msp != NULL) {
2355 capacity += msp->capacity_words(mdtype);
2356 }
2357 }
2358 return capacity * BytesPerWord;
2359 }
2361 size_t MetaspaceAux::reserved_in_bytes(Metaspace::MetadataType mdtype) {
2362 size_t reserved = (mdtype == Metaspace::ClassType) ?
2363 Metaspace::class_space_list()->virtual_space_total() :
2364 Metaspace::space_list()->virtual_space_total();
2365 return reserved * BytesPerWord;
2366 }
2368 size_t MetaspaceAux::min_chunk_size() { return Metaspace::first_chunk_word_size(); }
2370 size_t MetaspaceAux::free_chunks_total(Metaspace::MetadataType mdtype) {
2371 ChunkManager* chunk = (mdtype == Metaspace::ClassType) ?
2372 Metaspace::class_space_list()->chunk_manager() :
2373 Metaspace::space_list()->chunk_manager();
2374 chunk->slow_verify();
2375 return chunk->free_chunks_total();
2376 }
2378 size_t MetaspaceAux::free_chunks_total_in_bytes(Metaspace::MetadataType mdtype) {
2379 return free_chunks_total(mdtype) * BytesPerWord;
2380 }
2382 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) {
2383 gclog_or_tty->print(", [Metaspace:");
2384 if (PrintGCDetails && Verbose) {
2385 gclog_or_tty->print(" " SIZE_FORMAT
2386 "->" SIZE_FORMAT
2387 "(" SIZE_FORMAT "/" SIZE_FORMAT ")",
2388 prev_metadata_used,
2389 used_in_bytes(),
2390 capacity_in_bytes(),
2391 reserved_in_bytes());
2392 } else {
2393 gclog_or_tty->print(" " SIZE_FORMAT "K"
2394 "->" SIZE_FORMAT "K"
2395 "(" SIZE_FORMAT "K/" SIZE_FORMAT "K)",
2396 prev_metadata_used / K,
2397 used_in_bytes()/ K,
2398 capacity_in_bytes()/K,
2399 reserved_in_bytes()/ K);
2400 }
2402 gclog_or_tty->print("]");
2403 }
2405 // This is printed when PrintGCDetails
2406 void MetaspaceAux::print_on(outputStream* out) {
2407 Metaspace::MetadataType ct = Metaspace::ClassType;
2408 Metaspace::MetadataType nct = Metaspace::NonClassType;
2410 out->print_cr(" Metaspace total "
2411 SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
2412 " reserved " SIZE_FORMAT "K",
2413 capacity_in_bytes()/K, used_in_bytes()/K, reserved_in_bytes()/K);
2414 out->print_cr(" data space "
2415 SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
2416 " reserved " SIZE_FORMAT "K",
2417 capacity_in_bytes(nct)/K, used_in_bytes(nct)/K, reserved_in_bytes(nct)/K);
2418 out->print_cr(" class space "
2419 SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
2420 " reserved " SIZE_FORMAT "K",
2421 capacity_in_bytes(ct)/K, used_in_bytes(ct)/K, reserved_in_bytes(ct)/K);
2422 }
2424 // Print information for class space and data space separately.
2425 // This is almost the same as above.
2426 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) {
2427 size_t free_chunks_capacity_bytes = free_chunks_total_in_bytes(mdtype);
2428 size_t capacity_bytes = capacity_in_bytes(mdtype);
2429 size_t used_bytes = used_in_bytes(mdtype);
2430 size_t free_bytes = free_in_bytes(mdtype);
2431 size_t used_and_free = used_bytes + free_bytes +
2432 free_chunks_capacity_bytes;
2433 out->print_cr(" Chunk accounting: used in chunks " SIZE_FORMAT
2434 "K + unused in chunks " SIZE_FORMAT "K + "
2435 " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT
2436 "K capacity in allocated chunks " SIZE_FORMAT "K",
2437 used_bytes / K,
2438 free_bytes / K,
2439 free_chunks_capacity_bytes / K,
2440 used_and_free / K,
2441 capacity_bytes / K);
2442 assert(used_and_free == capacity_bytes, "Accounting is wrong");
2443 }
2445 // Print total fragmentation for class and data metaspaces separately
2446 void MetaspaceAux::print_waste(outputStream* out) {
2448 size_t specialized_waste = 0, small_waste = 0, medium_waste = 0, large_waste = 0;
2449 size_t specialized_count = 0, small_count = 0, medium_count = 0, large_count = 0;
2450 size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0, cls_large_waste = 0;
2451 size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_large_count = 0;
2453 ClassLoaderDataGraphMetaspaceIterator iter;
2454 while (iter.repeat()) {
2455 Metaspace* msp = iter.get_next();
2456 if (msp != NULL) {
2457 specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2458 specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2459 small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2460 small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex);
2461 medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2462 medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex);
2463 large_waste += msp->vsm()->sum_waste_in_chunks_in_use(HumongousIndex);
2464 large_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2466 cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex);
2467 cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex);
2468 cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex);
2469 cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex);
2470 cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex);
2471 cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex);
2472 cls_large_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(HumongousIndex);
2473 cls_large_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex);
2474 }
2475 }
2476 out->print_cr("Total fragmentation waste (words) doesn't count free space");
2477 out->print_cr(" data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2478 SIZE_FORMAT " small(s) " SIZE_FORMAT ", "
2479 SIZE_FORMAT " medium(s) " SIZE_FORMAT,
2480 specialized_count, specialized_waste, small_count,
2481 small_waste, medium_count, medium_waste);
2482 out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", "
2483 SIZE_FORMAT " small(s) " SIZE_FORMAT,
2484 cls_specialized_count, cls_specialized_waste,
2485 cls_small_count, cls_small_waste);
2486 }
2488 // Dump global metaspace things from the end of ClassLoaderDataGraph
2489 void MetaspaceAux::dump(outputStream* out) {
2490 out->print_cr("All Metaspace:");
2491 out->print("data space: "); print_on(out, Metaspace::NonClassType);
2492 out->print("class space: "); print_on(out, Metaspace::ClassType);
2493 print_waste(out);
2494 }
2496 void MetaspaceAux::verify_free_chunks() {
2497 Metaspace::space_list()->chunk_manager()->verify();
2498 Metaspace::class_space_list()->chunk_manager()->verify();
2499 }
2501 // Metaspace methods
2503 size_t Metaspace::_first_chunk_word_size = 0;
2504 size_t Metaspace::_first_class_chunk_word_size = 0;
2506 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) {
2507 initialize(lock, type);
2508 }
2510 Metaspace::~Metaspace() {
2511 delete _vsm;
2512 delete _class_vsm;
2513 }
2515 VirtualSpaceList* Metaspace::_space_list = NULL;
2516 VirtualSpaceList* Metaspace::_class_space_list = NULL;
2518 #define VIRTUALSPACEMULTIPLIER 2
2520 void Metaspace::global_initialize() {
2521 // Initialize the alignment for shared spaces.
2522 int max_alignment = os::vm_page_size();
2523 MetaspaceShared::set_max_alignment(max_alignment);
2525 if (DumpSharedSpaces) {
2526 SharedReadOnlySize = align_size_up(SharedReadOnlySize, max_alignment);
2527 SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment);
2528 SharedMiscDataSize = align_size_up(SharedMiscDataSize, max_alignment);
2529 SharedMiscCodeSize = align_size_up(SharedMiscCodeSize, max_alignment);
2531 // Initialize with the sum of the shared space sizes. The read-only
2532 // and read write metaspace chunks will be allocated out of this and the
2533 // remainder is the misc code and data chunks.
2534 size_t total = align_size_up(SharedReadOnlySize + SharedReadWriteSize +
2535 SharedMiscDataSize + SharedMiscCodeSize,
2536 os::vm_allocation_granularity());
2537 size_t word_size = total/wordSize;
2538 _space_list = new VirtualSpaceList(word_size);
2539 } else {
2540 // If using shared space, open the file that contains the shared space
2541 // and map in the memory before initializing the rest of metaspace (so
2542 // the addresses don't conflict)
2543 if (UseSharedSpaces) {
2544 FileMapInfo* mapinfo = new FileMapInfo();
2545 memset(mapinfo, 0, sizeof(FileMapInfo));
2547 // Open the shared archive file, read and validate the header. If
2548 // initialization fails, shared spaces [UseSharedSpaces] are
2549 // disabled and the file is closed.
2550 // Map in spaces now also
2551 if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) {
2552 FileMapInfo::set_current_info(mapinfo);
2553 } else {
2554 assert(!mapinfo->is_open() && !UseSharedSpaces,
2555 "archive file not closed or shared spaces not disabled.");
2556 }
2557 }
2559 // Initialize these before initializing the VirtualSpaceList
2560 _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord;
2561 _first_chunk_word_size = align_word_size_up(_first_chunk_word_size);
2562 // Make the first class chunk bigger than a medium chunk so it's not put
2563 // on the medium chunk list. The next chunk will be small and progress
2564 // from there. This size calculated by -version.
2565 _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6,
2566 (ClassMetaspaceSize/BytesPerWord)*2);
2567 _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size);
2568 // Arbitrarily set the initial virtual space to a multiple
2569 // of the boot class loader size.
2570 size_t word_size = VIRTUALSPACEMULTIPLIER * first_chunk_word_size();
2571 // Initialize the list of virtual spaces.
2572 _space_list = new VirtualSpaceList(word_size);
2573 }
2574 }
2576 // For UseCompressedKlassPointers the class space is reserved as a piece of the
2577 // Java heap because the compression algorithm is the same for each. The
2578 // argument passed in is at the top of the compressed space
2579 void Metaspace::initialize_class_space(ReservedSpace rs) {
2580 // The reserved space size may be bigger because of alignment, esp with UseLargePages
2581 assert(rs.size() >= ClassMetaspaceSize, err_msg("%d != %d", rs.size(), ClassMetaspaceSize));
2582 _class_space_list = new VirtualSpaceList(rs);
2583 }
2585 void Metaspace::initialize(Mutex* lock,
2586 MetaspaceType type) {
2588 assert(space_list() != NULL,
2589 "Metadata VirtualSpaceList has not been initialized");
2591 _vsm = new SpaceManager(lock, space_list());
2592 if (_vsm == NULL) {
2593 return;
2594 }
2595 size_t word_size;
2596 size_t class_word_size;
2597 vsm()->get_initial_chunk_sizes(type,
2598 &word_size,
2599 &class_word_size);
2601 assert(class_space_list() != NULL,
2602 "Class VirtualSpaceList has not been initialized");
2604 // Allocate SpaceManager for classes.
2605 _class_vsm = new SpaceManager(lock, class_space_list());
2606 if (_class_vsm == NULL) {
2607 return;
2608 }
2610 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
2612 // Allocate chunk for metadata objects
2613 Metachunk* new_chunk =
2614 space_list()->get_initialization_chunk(word_size,
2615 vsm()->medium_chunk_bunch());
2616 assert(!DumpSharedSpaces || new_chunk != NULL, "should have enough space for both chunks");
2617 if (new_chunk != NULL) {
2618 // Add to this manager's list of chunks in use and current_chunk().
2619 vsm()->add_chunk(new_chunk, true);
2620 }
2622 // Allocate chunk for class metadata objects
2623 Metachunk* class_chunk =
2624 class_space_list()->get_initialization_chunk(class_word_size,
2625 class_vsm()->medium_chunk_bunch());
2626 if (class_chunk != NULL) {
2627 class_vsm()->add_chunk(class_chunk, true);
2628 }
2629 }
2631 size_t Metaspace::align_word_size_up(size_t word_size) {
2632 size_t byte_size = word_size * wordSize;
2633 return ReservedSpace::allocation_align_size_up(byte_size) / wordSize;
2634 }
2636 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) {
2637 // DumpSharedSpaces doesn't use class metadata area (yet)
2638 if (mdtype == ClassType && !DumpSharedSpaces) {
2639 return class_vsm()->allocate(word_size);
2640 } else {
2641 return vsm()->allocate(word_size);
2642 }
2643 }
2645 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) {
2646 MetaWord* result;
2647 MetaspaceGC::set_expand_after_GC(true);
2648 size_t before_inc = MetaspaceGC::capacity_until_GC();
2649 size_t delta_words = MetaspaceGC::delta_capacity_until_GC(word_size);
2650 MetaspaceGC::inc_capacity_until_GC(delta_words);
2651 if (PrintGCDetails && Verbose) {
2652 gclog_or_tty->print_cr("Increase capacity to GC from " SIZE_FORMAT
2653 " to " SIZE_FORMAT, before_inc, MetaspaceGC::capacity_until_GC());
2654 }
2656 result = allocate(word_size, mdtype);
2658 return result;
2659 }
2661 // Space allocated in the Metaspace. This may
2662 // be across several metadata virtual spaces.
2663 char* Metaspace::bottom() const {
2664 assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces");
2665 return (char*)vsm()->current_chunk()->bottom();
2666 }
2668 size_t Metaspace::used_words(MetadataType mdtype) const {
2669 // return vsm()->allocation_total();
2670 return mdtype == ClassType ? class_vsm()->sum_used_in_chunks_in_use() :
2671 vsm()->sum_used_in_chunks_in_use(); // includes overhead!
2672 }
2674 size_t Metaspace::free_words(MetadataType mdtype) const {
2675 return mdtype == ClassType ? class_vsm()->sum_free_in_chunks_in_use() :
2676 vsm()->sum_free_in_chunks_in_use();
2677 }
2679 // Space capacity in the Metaspace. It includes
2680 // space in the list of chunks from which allocations
2681 // have been made. Don't include space in the global freelist and
2682 // in the space available in the dictionary which
2683 // is already counted in some chunk.
2684 size_t Metaspace::capacity_words(MetadataType mdtype) const {
2685 return mdtype == ClassType ? class_vsm()->sum_capacity_in_chunks_in_use() :
2686 vsm()->sum_capacity_in_chunks_in_use();
2687 }
2689 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
2690 if (SafepointSynchronize::is_at_safepoint()) {
2691 assert(Thread::current()->is_VM_thread(), "should be the VM thread");
2692 // Don't take Heap_lock
2693 MutexLocker ml(vsm()->lock());
2694 if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
2695 // Dark matter. Too small for dictionary.
2696 #ifdef ASSERT
2697 Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
2698 #endif
2699 return;
2700 }
2701 if (is_class) {
2702 class_vsm()->deallocate(ptr, word_size);
2703 } else {
2704 vsm()->deallocate(ptr, word_size);
2705 }
2706 } else {
2707 MutexLocker ml(vsm()->lock());
2709 if (word_size < TreeChunk<Metablock, FreeList>::min_size()) {
2710 // Dark matter. Too small for dictionary.
2711 #ifdef ASSERT
2712 Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5);
2713 #endif
2714 return;
2715 }
2716 if (is_class) {
2717 class_vsm()->deallocate(ptr, word_size);
2718 } else {
2719 vsm()->deallocate(ptr, word_size);
2720 }
2721 }
2722 }
2724 Metablock* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size,
2725 bool read_only, MetadataType mdtype, TRAPS) {
2726 if (HAS_PENDING_EXCEPTION) {
2727 assert(false, "Should not allocate with exception pending");
2728 return NULL; // caller does a CHECK_NULL too
2729 }
2731 // SSS: Should we align the allocations and make sure the sizes are aligned.
2732 MetaWord* result = NULL;
2734 assert(loader_data != NULL, "Should never pass around a NULL loader_data. "
2735 "ClassLoaderData::the_null_class_loader_data() should have been used.");
2736 // Allocate in metaspaces without taking out a lock, because it deadlocks
2737 // with the SymbolTable_lock. Dumping is single threaded for now. We'll have
2738 // to revisit this for application class data sharing.
2739 if (DumpSharedSpaces) {
2740 if (read_only) {
2741 result = loader_data->ro_metaspace()->allocate(word_size, NonClassType);
2742 } else {
2743 result = loader_data->rw_metaspace()->allocate(word_size, NonClassType);
2744 }
2745 if (result == NULL) {
2746 report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite);
2747 }
2748 return Metablock::initialize(result, word_size);
2749 }
2751 result = loader_data->metaspace_non_null()->allocate(word_size, mdtype);
2753 if (result == NULL) {
2754 // Try to clean out some memory and retry.
2755 result =
2756 Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation(
2757 loader_data, word_size, mdtype);
2759 // If result is still null, we are out of memory.
2760 if (result == NULL) {
2761 if (Verbose && TraceMetadataChunkAllocation) {
2762 gclog_or_tty->print_cr("Metaspace allocation failed for size "
2763 SIZE_FORMAT, word_size);
2764 if (loader_data->metaspace_or_null() != NULL) loader_data->metaspace_or_null()->dump(gclog_or_tty);
2765 MetaspaceAux::dump(gclog_or_tty);
2766 }
2767 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
2768 report_java_out_of_memory("Metadata space");
2770 if (JvmtiExport::should_post_resource_exhausted()) {
2771 JvmtiExport::post_resource_exhausted(
2772 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
2773 "Metadata space");
2774 }
2775 THROW_OOP_0(Universe::out_of_memory_error_perm_gen());
2776 }
2777 }
2778 return Metablock::initialize(result, word_size);
2779 }
2781 void Metaspace::print_on(outputStream* out) const {
2782 // Print both class virtual space counts and metaspace.
2783 if (Verbose) {
2784 vsm()->print_on(out);
2785 class_vsm()->print_on(out);
2786 }
2787 }
2789 bool Metaspace::contains(const void * ptr) {
2790 if (MetaspaceShared::is_in_shared_space(ptr)) {
2791 return true;
2792 }
2793 // This is checked while unlocked. As long as the virtualspaces are added
2794 // at the end, the pointer will be in one of them. The virtual spaces
2795 // aren't deleted presently. When they are, some sort of locking might
2796 // be needed. Note, locking this can cause inversion problems with the
2797 // caller in MetaspaceObj::is_metadata() function.
2798 return space_list()->contains(ptr) || class_space_list()->contains(ptr);
2799 }
2801 void Metaspace::verify() {
2802 vsm()->verify();
2803 class_vsm()->verify();
2804 }
2806 void Metaspace::dump(outputStream* const out) const {
2807 if (UseMallocOnly) {
2808 // Just print usage for now
2809 out->print_cr("usage %d", used_words(Metaspace::NonClassType));
2810 }
2811 out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, vsm());
2812 vsm()->dump(out);
2813 out->print_cr("\nClass space manager: " INTPTR_FORMAT, class_vsm());
2814 class_vsm()->dump(out);
2815 }