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" 43 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; 49 50 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; 56 57 MetaWord* last_allocated = 0; 58 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 }; 69 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 }; 79 80 static ChunkIndex next_chunk_index(ChunkIndex i) { 81 assert(i < NumberOfInUseLists, "Out of bound"); 82 return (ChunkIndex) (i+1); 83 } 84 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; 94 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. 106 107 // Pointer to list of Metachunks. 108 class ChunkList VALUE_OBJ_CLASS_SPEC { 109 // List of free chunks 110 Metachunk* _head; 111 112 public: 113 // Constructor 114 ChunkList() : _head(NULL) {} 115 116 // Accessors 117 Metachunk* head() { return _head; } 118 void set_head(Metachunk* v) { _head = v; } 119 120 // Link at head of the list 121 void add_at_head(Metachunk* head, Metachunk* tail); 122 void add_at_head(Metachunk* head); 123 124 size_t sum_list_size(); 125 size_t sum_list_count(); 126 size_t sum_list_capacity(); 127 }; 128 129 // 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 132 133 class ChunkManager VALUE_OBJ_CLASS_SPEC { 134 135 // Free list of chunks of different sizes. 136 // SmallChunk 137 // MediumChunk 138 // HumongousChunk 139 ChunkList _free_chunks[NumberOfFreeLists]; 140 141 142 // HumongousChunk 143 ChunkTreeDictionary _humongous_dictionary; 144 145 // ChunkManager in all lists of this type 146 size_t _free_chunks_total; 147 size_t _free_chunks_count; 148 149 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 } 157 158 // Debug support 159 160 size_t sum_free_chunks(); 161 size_t sum_free_chunks_count(); 162 163 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(); 176 177 public: 178 179 ChunkManager() : _free_chunks_total(0), _free_chunks_count(0) {} 180 181 // 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); 184 185 // 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); 188 189 // Total of the space in the free chunks list 190 size_t free_chunks_total(); 191 size_t free_chunks_total_in_bytes(); 192 193 // Number of chunks in the free chunks list 194 size_t free_chunks_count(); 195 196 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 } 203 204 ChunkList* free_chunks(ChunkIndex index); 205 206 // Returns the list for the given chunk word size. 207 ChunkList* find_free_chunks_list(size_t word_size); 208 209 // 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); 213 214 // 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(); 228 229 void locked_print_free_chunks(outputStream* st); 230 void locked_print_sum_free_chunks(outputStream* st); 231 232 void print_on(outputStream* st); 233 }; 234 235 236 // 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); 241 242 // Accessors 243 BlockTreeDictionary* dictionary() const { return _dictionary; } 244 245 public: 246 BlockFreelist(); 247 ~BlockFreelist(); 248 249 // 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); 252 253 size_t total_size() { 254 if (dictionary() == NULL) { 255 return 0; 256 } else { 257 return dictionary()->total_size(); 258 } 259 } 260 261 void print_on(outputStream* st) const; 262 }; 263 264 class VirtualSpaceNode : public CHeapObj<mtClass> { 265 friend class VirtualSpaceList; 266 267 // Link to next VirtualSpaceNode 268 VirtualSpaceNode* _next; 269 270 // total in the VirtualSpace 271 MemRegion _reserved; 272 ReservedSpace _rs; 273 VirtualSpace _virtual_space; 274 MetaWord* _top; 275 276 // 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(); } 279 280 // Convenience functions to access the _virtual_space 281 char* low() const { return virtual_space()->low(); } 282 char* high() const { return virtual_space()->high(); } 283 284 public: 285 286 VirtualSpaceNode(size_t byte_size); 287 VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs) {} 288 ~VirtualSpaceNode(); 289 290 // address of next available space in _virtual_space; 291 // Accessors 292 VirtualSpaceNode* next() { return _next; } 293 void set_next(VirtualSpaceNode* v) { _next = v; } 294 295 void set_reserved(MemRegion const v) { _reserved = v; } 296 void set_top(MetaWord* v) { _top = v; } 297 298 // Accessors 299 MemRegion* reserved() { return &_reserved; } 300 VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; } 301 302 // Returns true if "word_size" is available in the virtual space 303 bool is_available(size_t word_size) { return _top + word_size <= end(); } 304 305 MetaWord* top() const { return _top; } 306 void inc_top(size_t word_size) { _top += word_size; } 307 308 // 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; 311 312 bool initialize(); 313 314 // get space from the virtual space 315 Metachunk* take_from_committed(size_t chunk_word_size); 316 317 // 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); 320 321 // 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); 325 326 #ifdef ASSERT 327 // Debug support 328 static void verify_virtual_space_total(); 329 static void verify_virtual_space_count(); 330 void mangle(); 331 #endif 332 333 void print_on(outputStream* st) const; 334 }; 335 336 // 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 } 365 366 MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass); 367 } 368 369 // 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; 374 375 enum VirtualSpaceSizes { 376 VirtualSpaceSize = 256 * K 377 }; 378 379 // 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; 386 387 // 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; } 391 392 // Sum of space in all virtual spaces and number of virtual spaces 393 size_t _virtual_space_total; 394 size_t _virtual_space_count; 395 396 ~VirtualSpaceList(); 397 398 VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; } 399 400 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 } 406 407 void link_vs(VirtualSpaceNode* new_entry, size_t vs_word_size); 408 409 // 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); 413 414 public: 415 VirtualSpaceList(size_t word_size); 416 VirtualSpaceList(ReservedSpace rs); 417 418 Metachunk* get_new_chunk(size_t word_size, 419 size_t grow_chunks_by_words, 420 size_t medium_chunk_bunch); 421 422 // 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); 426 427 VirtualSpaceNode* current_virtual_space() { 428 return _current_virtual_space; 429 } 430 431 ChunkManager* chunk_manager() { return &_chunk_manager; } 432 bool is_class() const { return _is_class; } 433 434 // Allocate the first virtualspace. 435 void initialize(size_t word_size); 436 437 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 } 441 442 size_t virtual_space_count() { return _virtual_space_count; } 443 void inc_virtual_space_count() { 444 Atomic::inc_ptr(&_virtual_space_count); 445 } 446 447 // 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; } 453 454 bool contains(const void *ptr); 455 456 void print_on(outputStream* st) const; 457 458 class VirtualSpaceListIterator : public StackObj { 459 VirtualSpaceNode* _virtual_spaces; 460 public: 461 VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) : 462 _virtual_spaces(virtual_spaces) {} 463 464 bool repeat() { 465 return _virtual_spaces != NULL; 466 } 467 468 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 }; 477 478 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; 483 484 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 } 503 504 static void init_allocation_fail_alot_count(); 505 #ifdef ASSERT 506 static bool test_metadata_failure(); 507 #endif 508 509 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); 513 514 }; 515 516 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; 519 520 // SpaceManager - used by Metaspace to handle allocations 521 class SpaceManager : public CHeapObj<mtClass> { 522 friend class Metaspace; 523 friend class Metadebug; 524 525 private: 526 527 // protects allocations and contains. 528 Mutex* const _lock; 529 530 // Chunk related size 531 size_t _medium_chunk_bunch; 532 533 // 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; 538 539 // Virtual space where allocation comes from. 540 VirtualSpaceList* _vs_list; 541 542 // 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(); } 546 547 // Sum of all space in allocated chunks 548 size_t _allocation_total; 549 550 // 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; 555 556 // 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; 560 561 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; } 565 566 BlockFreelist* block_freelists() const { 567 return (BlockFreelist*) &_block_freelists; 568 } 569 570 VirtualSpaceList* vs_list() const { return _vs_list; } 571 572 Metachunk* current_chunk() const { return _current_chunk; } 573 void set_current_chunk(Metachunk* v) { 574 _current_chunk = v; 575 } 576 577 Metachunk* find_current_chunk(size_t word_size); 578 579 // Add chunk to the list of chunks in use 580 void add_chunk(Metachunk* v, bool make_current); 581 582 Mutex* lock() const { return _lock; } 583 584 const char* chunk_size_name(ChunkIndex index) const; 585 586 protected: 587 void initialize(); 588 589 public: 590 SpaceManager(Mutex* lock, 591 VirtualSpaceList* vs_list); 592 ~SpaceManager(); 593 594 enum ChunkMultiples { 595 MediumChunkMultiple = 4 596 }; 597 598 // 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; } 603 604 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(); } 607 608 static Mutex* expand_lock() { return _expand_lock; } 609 610 // 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); 614 615 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; 620 621 size_t sum_count_in_chunks_in_use(); 622 size_t sum_count_in_chunks_in_use(ChunkIndex i); 623 624 Metachunk* get_new_chunk(size_t word_size, size_t grow_chunks_by_words); 625 626 // Block allocation and deallocation. 627 // Allocates a block from the current chunk 628 MetaWord* allocate(size_t word_size); 629 630 // Helper for allocations 631 MetaWord* allocate_work(size_t word_size); 632 633 // Returns a block to the per manager freelist 634 void deallocate(MetaWord* p, size_t word_size); 635 636 // 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); 639 640 // 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); 644 645 // debugging support. 646 647 void dump(outputStream* const out) const; 648 void print_on(outputStream* st) const; 649 void locked_print_chunks_in_use_on(outputStream* st) const; 650 651 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 }; 658 659 uint const SpaceManager::_small_chunk_limit = 4; 660 661 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); 668 669 // BlockFreelist methods 670 671 BlockFreelist::BlockFreelist() : _dictionary(NULL) {} 672 673 BlockFreelist::~BlockFreelist() { 674 if (_dictionary != NULL) { 675 if (Verbose && TraceMetadataChunkAllocation) { 676 _dictionary->print_free_lists(gclog_or_tty); 677 } 678 delete _dictionary; 679 } 680 } 681 682 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); 687 688 return block; 689 } 690 691 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, false); 697 } 698 699 MetaWord* BlockFreelist::get_block(size_t word_size) { 700 if (dictionary() == NULL) { 701 return NULL; 702 } 703 704 if (word_size < TreeChunk<Metablock, FreeList>::min_size()) { 705 // Dark matter. Too small for dictionary. 706 return NULL; 707 } 708 709 Metablock* free_block = 710 dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::exactly); 711 if (free_block == NULL) { 712 return NULL; 713 } 714 715 return (MetaWord*) free_block; 716 } 717 718 void BlockFreelist::print_on(outputStream* st) const { 719 if (dictionary() == NULL) { 720 return; 721 } 722 dictionary()->print_free_lists(st); 723 } 724 725 // VirtualSpaceNode methods 726 727 VirtualSpaceNode::~VirtualSpaceNode() { 728 _rs.release(); 729 } 730 731 size_t VirtualSpaceNode::used_words_in_vs() const { 732 return pointer_delta(top(), bottom(), sizeof(MetaWord)); 733 } 734 735 // Space committed in the VirtualSpace 736 size_t VirtualSpaceNode::capacity_words_in_vs() const { 737 return pointer_delta(end(), bottom(), sizeof(MetaWord)); 738 } 739 740 741 // 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"); 748 749 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 } 757 758 // Take the space (bump top on the current virtual space). 759 inc_top(chunk_word_size); 760 761 // Point the chunk at the space 762 Metachunk* result = Metachunk::initialize(chunk_limit, chunk_word_size); 763 return result; 764 } 765 766 767 // 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 } 778 779 // 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 } 785 786 // Add another chunk to the chunk list. 787 788 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) { 789 assert_lock_strong(SpaceManager::expand_lock()); 790 Metachunk* result = NULL; 791 792 return take_from_committed(chunk_word_size); 793 } 794 795 Metachunk* VirtualSpaceNode::get_chunk_vs_with_expand(size_t chunk_word_size) { 796 assert_lock_strong(SpaceManager::expand_lock()); 797 798 Metachunk* new_chunk = get_chunk_vs(chunk_word_size); 799 800 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 } 811 812 bool VirtualSpaceNode::initialize() { 813 814 if (!_rs.is_reserved()) { 815 return false; 816 } 817 818 // 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()))); 827 828 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 } 836 837 return result; 838 } 839 840 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 } 852 853 #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 859 860 // VirtualSpaceList methods 861 // Space allocated from the VirtualSpace 862 863 VirtualSpaceList::~VirtualSpaceList() { 864 VirtualSpaceListIterator iter(virtual_space_list()); 865 while (iter.repeat()) { 866 VirtualSpaceNode* vsl = iter.get_next(); 867 delete vsl; 868 } 869 } 870 871 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 } 887 888 // 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 } 900 901 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); 910 911 assert(initialization_succeeded, 912 " VirtualSpaceList initialization should not fail"); 913 } 914 915 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 } 928 929 // 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"); 938 939 // 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 } 951 952 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 } 969 970 Metachunk* VirtualSpaceList::get_new_chunk(size_t word_size, 971 size_t grow_chunks_by_words, 972 size_t medium_chunk_bunch) { 973 974 // Get a chunk from the chunk freelist 975 Metachunk* next = chunk_manager()->chunk_freelist_allocate(grow_chunks_by_words); 976 977 // 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 } 981 982 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 } 1017 1018 assert(next == NULL || (next->next() == NULL && next->prev() == NULL), 1019 "New chunk is still on some list"); 1020 return next; 1021 } 1022 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 } 1031 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 } 1041 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 } 1053 1054 1055 // MetaspaceGC methods 1056 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. 1074 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 } 1102 1103 bool MetaspaceGC::should_expand(VirtualSpaceList* vsl, size_t word_size) { 1104 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; 1108 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 } 1116 1117 // If this is part of an allocation after a GC, expand 1118 // unconditionally. 1119 if(MetaspaceGC::expand_after_GC()) { 1120 return true; 1121 } 1122 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 } 1153 1154 // Variables are in bytes 1155 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; 1160 1161 VirtualSpaceList *vsl = Metaspace::space_list(); 1162 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; 1168 1169 const double minimum_free_percentage = MinHeapFreeRatio / 100.0; 1170 const double maximum_used_percentage = 1.0 - minimum_free_percentage; 1171 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); 1178 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 } 1201 1202 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 } 1226 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)); 1233 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 } 1256 1257 assert(minimum_desired_capacity <= maximum_desired_capacity, 1258 "sanity check"); 1259 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 } 1297 1298 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"); 1315 1316 } 1317 1318 // Metadebug methods 1319 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); 1333 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 } 1348 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 } 1367 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 } 1374 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 1393 1394 // ChunkList methods 1395 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 } 1405 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 } 1415 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 } 1425 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"); 1430 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 } 1440 1441 if (tail != NULL) { 1442 tail->set_next(_head); 1443 } 1444 set_head(head); 1445 } 1446 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 } 1463 1464 // ChunkManager methods 1465 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. 1470 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 } 1481 1482 size_t ChunkManager::free_chunks_total_in_bytes() { 1483 return free_chunks_total() * BytesPerWord; 1484 } 1485 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 } 1498 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 } 1506 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 } 1512 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 } 1520 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 } 1528 1529 void ChunkManager::verify() { 1530 MutexLockerEx cl(SpaceManager::expand_lock(), 1531 Mutex::_no_safepoint_check_flag); 1532 locked_verify(); 1533 } 1534 1535 void ChunkManager::locked_verify() { 1536 locked_verify_free_chunks_count(); 1537 locked_verify_free_chunks_total(); 1538 } 1539 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 } 1545 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 } 1554 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); 1562 1563 if (list == NULL) { 1564 continue; 1565 } 1566 1567 result = result + list->sum_list_capacity(); 1568 } 1569 result = result + humongous_dictionary()->total_size(); 1570 return result; 1571 } 1572 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 } 1586 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 } 1592 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 } 1602 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 } 1617 1618 Metachunk* ChunkManager::free_chunks_get(size_t word_size) { 1619 assert_lock_strong(SpaceManager::expand_lock()); 1620 1621 slow_locked_verify(); 1622 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"); 1627 1628 chunk = free_list->head(); 1629 debug_only(Metachunk* debug_head = chunk;) 1630 1631 if (chunk == NULL) { 1632 return NULL; 1633 } 1634 1635 // Remove the chunk as the head of the list. 1636 free_list->set_head(chunk->next()); 1637 1638 // Chunk is being removed from the chunks free list. 1639 dec_free_chunks_total(chunk->capacity_word_size()); 1640 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); 1650 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 } 1668 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 } 1675 1676 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) { 1677 assert_lock_strong(SpaceManager::expand_lock()); 1678 slow_locked_verify(); 1679 1680 // Take from the beginning of the list 1681 Metachunk* chunk = free_chunks_get(word_size); 1682 if (chunk == NULL) { 1683 return NULL; 1684 } 1685 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 } 1702 1703 return chunk; 1704 } 1705 1706 void ChunkManager::print_on(outputStream* out) { 1707 if (PrintFLSStatistics != 0) { 1708 humongous_dictionary()->report_statistics(); 1709 } 1710 } 1711 1712 // SpaceManager methods 1713 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 } 1745 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 } 1758 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 } 1765 1766 return result; 1767 } 1768 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 } 1784 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 } 1799 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 } 1805 1806 return count; 1807 } 1808 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 } 1818 1819 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 } 1832 1833 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const { 1834 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 } 1846 1847 vs_list()->chunk_manager()->locked_print_free_chunks(st); 1848 vs_list()->chunk_manager()->locked_print_sum_free_chunks(st); 1849 } 1850 1851 size_t SpaceManager::calc_chunk_size(size_t word_size) { 1852 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 } 1868 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); 1877 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 } 1894 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); 1902 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 } 1915 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); 1919 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 } 1930 1931 void SpaceManager::print_on(outputStream* st) const { 1932 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 } 1951 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 } 1960 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 } 1971 1972 SpaceManager::~SpaceManager() { 1973 MutexLockerEx fcl(SpaceManager::expand_lock(), 1974 Mutex::_no_safepoint_check_flag); 1975 1976 ChunkManager* chunk_manager = vs_list()->chunk_manager(); 1977 1978 chunk_manager->slow_locked_verify(); 1979 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 } 1984 1985 // Mangle freed memory. 1986 NOT_PRODUCT(mangle_freed_chunks();) 1987 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()); 1992 1993 // Add all the chunks in use by this space manager 1994 // to the global list of free chunks. 1995 1996 // Follow each list of chunks-in-use and add them to the 1997 // free lists. Each list is NULL terminated. 1998 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 } 2015 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. 2019 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); 2029 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, false); 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 } 2058 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 } 2073 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 } 2092 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 } 2100 2101 // Adds a chunk to the list of chunks in use. 2102 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) { 2103 2104 assert(new_chunk != NULL, "Should not be NULL"); 2105 assert(new_chunk->next() == NULL, "Should not be on a list"); 2106 2107 new_chunk->reset_empty(); 2108 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()); 2112 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); 2131 2132 assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency"); 2133 } 2134 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 } 2143 2144 Metachunk* SpaceManager::get_new_chunk(size_t word_size, 2145 size_t grow_chunks_by_words) { 2146 2147 Metachunk* next = vs_list()->get_new_chunk(word_size, 2148 grow_chunks_by_words, 2149 medium_chunk_bunch()); 2150 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 } 2156 2157 return next; 2158 } 2159 2160 MetaWord* SpaceManager::allocate(size_t word_size) { 2161 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2162 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; 2167 2168 size_t byte_size_with_overhead = byte_size + Metablock::overhead(); 2169 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"); 2175 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); 2190 2191 return p; 2192 } 2193 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; 2205 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 } 2217 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 } 2226 2227 return result; 2228 } 2229 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 } 2245 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 } 2254 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 } 2270 2271 #endif 2272 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; 2279 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 } 2298 2299 size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size(); 2300 // Free space isn't wasted. 2301 waste -= free; 2302 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 } 2307 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 2321 2322 // MetaspaceAux 2323 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 } 2336 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 } 2348 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 } 2360 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 } 2367 2368 size_t MetaspaceAux::min_chunk_size() { return Metaspace::first_chunk_word_size(); } 2369 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 } 2377 2378 size_t MetaspaceAux::free_chunks_total_in_bytes(Metaspace::MetadataType mdtype) { 2379 return free_chunks_total(mdtype) * BytesPerWord; 2380 } 2381 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 } 2401 2402 gclog_or_tty->print("]"); 2403 } 2404 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; 2409 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 } 2423 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 } 2444 2445 // Print total fragmentation for class and data metaspaces separately 2446 void MetaspaceAux::print_waste(outputStream* out) { 2447 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; 2452 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); 2465 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 } 2487 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 } 2495 2496 void MetaspaceAux::verify_free_chunks() { 2497 Metaspace::space_list()->chunk_manager()->verify(); 2498 Metaspace::class_space_list()->chunk_manager()->verify(); 2499 } 2500 2501 // Metaspace methods 2502 2503 size_t Metaspace::_first_chunk_word_size = 0; 2504 size_t Metaspace::_first_class_chunk_word_size = 0; 2505 2506 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) { 2507 initialize(lock, type); 2508 } 2509 2510 Metaspace::~Metaspace() { 2511 delete _vsm; 2512 delete _class_vsm; 2513 } 2514 2515 VirtualSpaceList* Metaspace::_space_list = NULL; 2516 VirtualSpaceList* Metaspace::_class_space_list = NULL; 2517 2518 #define VIRTUALSPACEMULTIPLIER 2 2519 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); 2524 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); 2530 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)); 2546 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 } 2558 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 } 2575 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 } 2584 2585 void Metaspace::initialize(Mutex* lock, 2586 MetaspaceType type) { 2587 2588 assert(space_list() != NULL, 2589 "Metadata VirtualSpaceList has not been initialized"); 2590 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); 2600 2601 assert(class_space_list() != NULL, 2602 "Class VirtualSpaceList has not been initialized"); 2603 2604 // Allocate SpaceManager for classes. 2605 _class_vsm = new SpaceManager(lock, class_space_list()); 2606 if (_class_vsm == NULL) { 2607 return; 2608 } 2609 2610 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 2611 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 } 2621 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 } 2630 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 } 2635 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 } 2644 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 } 2655 2656 result = allocate(word_size, mdtype); 2657 2658 return result; 2659 } 2660 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 } 2667 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 } 2673 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 } 2678 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 } 2688 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()); 2708 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 } 2723 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 } 2730 2731 // SSS: Should we align the allocations and make sure the sizes are aligned. 2732 MetaWord* result = NULL; 2733 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 } 2750 2751 result = loader_data->metaspace_non_null()->allocate(word_size, mdtype); 2752 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); 2758 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"); 2769 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 } 2780 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 } 2788 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 } 2800 2801 void Metaspace::verify() { 2802 vsm()->verify(); 2803 class_vsm()->verify(); 2804 } 2805 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 }