1 /* 2 * Copyright (c) 2011, 2016, 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/shared/collectedHeap.hpp" 26 #include "gc/shared/collectorPolicy.hpp" 27 #include "gc/shared/gcLocker.hpp" 28 #include "logging/log.hpp" 29 #include "memory/allocation.hpp" 30 #include "memory/binaryTreeDictionary.hpp" 31 #include "memory/filemap.hpp" 32 #include "memory/freeList.hpp" 33 #include "memory/metachunk.hpp" 34 #include "memory/metaspace.hpp" 35 #include "memory/metaspaceGCThresholdUpdater.hpp" 36 #include "memory/metaspaceShared.hpp" 37 #include "memory/metaspaceTracer.hpp" 38 #include "memory/resourceArea.hpp" 39 #include "memory/universe.hpp" 40 #include "runtime/atomic.hpp" 41 #include "runtime/globals.hpp" 42 #include "runtime/init.hpp" 43 #include "runtime/java.hpp" 44 #include "runtime/mutex.hpp" 45 #include "runtime/orderAccess.inline.hpp" 46 #include "services/memTracker.hpp" 47 #include "services/memoryService.hpp" 48 #include "utilities/copy.hpp" 49 #include "utilities/debug.hpp" 50 #include "utilities/macros.hpp" 51 52 typedef BinaryTreeDictionary<Metablock, FreeList<Metablock> > BlockTreeDictionary; 53 typedef BinaryTreeDictionary<Metachunk, FreeList<Metachunk> > ChunkTreeDictionary; 54 55 // Set this constant to enable slow integrity checking of the free chunk lists 56 const bool metaspace_slow_verify = false; 57 58 size_t const allocation_from_dictionary_limit = 4 * K; 59 60 MetaWord* last_allocated = 0; 61 62 size_t Metaspace::_compressed_class_space_size; 63 const MetaspaceTracer* Metaspace::_tracer = NULL; 64 65 // Used in declarations in SpaceManager and ChunkManager 66 enum ChunkIndex { 67 ZeroIndex = 0, 68 SpecializedIndex = ZeroIndex, 69 SmallIndex = SpecializedIndex + 1, 70 MediumIndex = SmallIndex + 1, 71 HumongousIndex = MediumIndex + 1, 72 NumberOfFreeLists = 3, 73 NumberOfInUseLists = 4 74 }; 75 76 enum ChunkSizes { // in words. 77 ClassSpecializedChunk = 128, 78 SpecializedChunk = 128, 79 ClassSmallChunk = 256, 80 SmallChunk = 512, 81 ClassMediumChunk = 4 * K, 82 MediumChunk = 8 * K 83 }; 84 85 static ChunkIndex next_chunk_index(ChunkIndex i) { 86 assert(i < NumberOfInUseLists, "Out of bound"); 87 return (ChunkIndex) (i+1); 88 } 89 90 volatile intptr_t MetaspaceGC::_capacity_until_GC = 0; 91 uint MetaspaceGC::_shrink_factor = 0; 92 bool MetaspaceGC::_should_concurrent_collect = false; 93 94 typedef class FreeList<Metachunk> ChunkList; 95 96 // Manages the global free lists of chunks. 97 class ChunkManager : public CHeapObj<mtInternal> { 98 friend class TestVirtualSpaceNodeTest; 99 100 // Free list of chunks of different sizes. 101 // SpecializedChunk 102 // SmallChunk 103 // MediumChunk 104 // HumongousChunk 105 ChunkList _free_chunks[NumberOfFreeLists]; 106 107 // HumongousChunk 108 ChunkTreeDictionary _humongous_dictionary; 109 110 // ChunkManager in all lists of this type 111 size_t _free_chunks_total; 112 size_t _free_chunks_count; 113 114 void dec_free_chunks_total(size_t v) { 115 assert(_free_chunks_count > 0 && 116 _free_chunks_total > 0, 117 "About to go negative"); 118 Atomic::add_ptr(-1, &_free_chunks_count); 119 jlong minus_v = (jlong) - (jlong) v; 120 Atomic::add_ptr(minus_v, &_free_chunks_total); 121 } 122 123 // Debug support 124 125 size_t sum_free_chunks(); 126 size_t sum_free_chunks_count(); 127 128 void locked_verify_free_chunks_total(); 129 void slow_locked_verify_free_chunks_total() { 130 if (metaspace_slow_verify) { 131 locked_verify_free_chunks_total(); 132 } 133 } 134 void locked_verify_free_chunks_count(); 135 void slow_locked_verify_free_chunks_count() { 136 if (metaspace_slow_verify) { 137 locked_verify_free_chunks_count(); 138 } 139 } 140 void verify_free_chunks_count(); 141 142 public: 143 144 ChunkManager(size_t specialized_size, size_t small_size, size_t medium_size) 145 : _free_chunks_total(0), _free_chunks_count(0) { 146 _free_chunks[SpecializedIndex].set_size(specialized_size); 147 _free_chunks[SmallIndex].set_size(small_size); 148 _free_chunks[MediumIndex].set_size(medium_size); 149 } 150 151 // add or delete (return) a chunk to the global freelist. 152 Metachunk* chunk_freelist_allocate(size_t word_size); 153 154 // Map a size to a list index assuming that there are lists 155 // for special, small, medium, and humongous chunks. 156 static ChunkIndex list_index(size_t size); 157 158 // Remove the chunk from its freelist. It is 159 // expected to be on one of the _free_chunks[] lists. 160 void remove_chunk(Metachunk* chunk); 161 162 // Add the simple linked list of chunks to the freelist of chunks 163 // of type index. 164 void return_chunks(ChunkIndex index, Metachunk* chunks); 165 166 // Total of the space in the free chunks list 167 size_t free_chunks_total_words(); 168 size_t free_chunks_total_bytes(); 169 170 // Number of chunks in the free chunks list 171 size_t free_chunks_count(); 172 173 void inc_free_chunks_total(size_t v, size_t count = 1) { 174 Atomic::add_ptr(count, &_free_chunks_count); 175 Atomic::add_ptr(v, &_free_chunks_total); 176 } 177 ChunkTreeDictionary* humongous_dictionary() { 178 return &_humongous_dictionary; 179 } 180 181 ChunkList* free_chunks(ChunkIndex index); 182 183 // Returns the list for the given chunk word size. 184 ChunkList* find_free_chunks_list(size_t word_size); 185 186 // Remove from a list by size. Selects list based on size of chunk. 187 Metachunk* free_chunks_get(size_t chunk_word_size); 188 189 #define index_bounds_check(index) \ 190 assert(index == SpecializedIndex || \ 191 index == SmallIndex || \ 192 index == MediumIndex || \ 193 index == HumongousIndex, "Bad index: %d", (int) index) 194 195 size_t num_free_chunks(ChunkIndex index) const { 196 index_bounds_check(index); 197 198 if (index == HumongousIndex) { 199 return _humongous_dictionary.total_free_blocks(); 200 } 201 202 ssize_t count = _free_chunks[index].count(); 203 return count == -1 ? 0 : (size_t) count; 204 } 205 206 size_t size_free_chunks_in_bytes(ChunkIndex index) const { 207 index_bounds_check(index); 208 209 size_t word_size = 0; 210 if (index == HumongousIndex) { 211 word_size = _humongous_dictionary.total_size(); 212 } else { 213 const size_t size_per_chunk_in_words = _free_chunks[index].size(); 214 word_size = size_per_chunk_in_words * num_free_chunks(index); 215 } 216 217 return word_size * BytesPerWord; 218 } 219 220 MetaspaceChunkFreeListSummary chunk_free_list_summary() const { 221 return MetaspaceChunkFreeListSummary(num_free_chunks(SpecializedIndex), 222 num_free_chunks(SmallIndex), 223 num_free_chunks(MediumIndex), 224 num_free_chunks(HumongousIndex), 225 size_free_chunks_in_bytes(SpecializedIndex), 226 size_free_chunks_in_bytes(SmallIndex), 227 size_free_chunks_in_bytes(MediumIndex), 228 size_free_chunks_in_bytes(HumongousIndex)); 229 } 230 231 // Debug support 232 void verify(); 233 void slow_verify() { 234 if (metaspace_slow_verify) { 235 verify(); 236 } 237 } 238 void locked_verify(); 239 void slow_locked_verify() { 240 if (metaspace_slow_verify) { 241 locked_verify(); 242 } 243 } 244 void verify_free_chunks_total(); 245 246 void locked_print_free_chunks(outputStream* st); 247 void locked_print_sum_free_chunks(outputStream* st); 248 249 void print_on(outputStream* st) const; 250 }; 251 252 class SmallBlocks : public CHeapObj<mtClass> { 253 const static uint _small_block_max_size = sizeof(TreeChunk<Metablock, FreeList<Metablock> >)/HeapWordSize; 254 const static uint _small_block_min_size = sizeof(Metablock)/HeapWordSize; 255 256 private: 257 FreeList<Metablock> _small_lists[_small_block_max_size - _small_block_min_size]; 258 259 FreeList<Metablock>& list_at(size_t word_size) { 260 assert(word_size >= _small_block_min_size, "There are no metaspace objects less than %u words", _small_block_min_size); 261 return _small_lists[word_size - _small_block_min_size]; 262 } 263 264 public: 265 SmallBlocks() { 266 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 267 uint k = i - _small_block_min_size; 268 _small_lists[k].set_size(i); 269 } 270 } 271 272 size_t total_size() const { 273 size_t result = 0; 274 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 275 uint k = i - _small_block_min_size; 276 result = result + _small_lists[k].count() * _small_lists[k].size(); 277 } 278 return result; 279 } 280 281 static uint small_block_max_size() { return _small_block_max_size; } 282 static uint small_block_min_size() { return _small_block_min_size; } 283 284 MetaWord* get_block(size_t word_size) { 285 if (list_at(word_size).count() > 0) { 286 MetaWord* new_block = (MetaWord*) list_at(word_size).get_chunk_at_head(); 287 return new_block; 288 } else { 289 return NULL; 290 } 291 } 292 void return_block(Metablock* free_chunk, size_t word_size) { 293 list_at(word_size).return_chunk_at_head(free_chunk, false); 294 assert(list_at(word_size).count() > 0, "Should have a chunk"); 295 } 296 297 void print_on(outputStream* st) const { 298 st->print_cr("SmallBlocks:"); 299 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 300 uint k = i - _small_block_min_size; 301 st->print_cr("small_lists size " SIZE_FORMAT " count " SIZE_FORMAT, _small_lists[k].size(), _small_lists[k].count()); 302 } 303 } 304 }; 305 306 // Used to manage the free list of Metablocks (a block corresponds 307 // to the allocation of a quantum of metadata). 308 class BlockFreelist : public CHeapObj<mtClass> { 309 BlockTreeDictionary* const _dictionary; 310 SmallBlocks* _small_blocks; 311 312 // Only allocate and split from freelist if the size of the allocation 313 // is at least 1/4th the size of the available block. 314 const static int WasteMultiplier = 4; 315 316 // Accessors 317 BlockTreeDictionary* dictionary() const { return _dictionary; } 318 SmallBlocks* small_blocks() { 319 if (_small_blocks == NULL) { 320 _small_blocks = new SmallBlocks(); 321 } 322 return _small_blocks; 323 } 324 325 public: 326 BlockFreelist(); 327 ~BlockFreelist(); 328 329 // Get and return a block to the free list 330 MetaWord* get_block(size_t word_size); 331 void return_block(MetaWord* p, size_t word_size); 332 333 size_t total_size() const { 334 size_t result = dictionary()->total_size(); 335 if (_small_blocks != NULL) { 336 result = result + _small_blocks->total_size(); 337 } 338 return result; 339 } 340 341 static size_t min_dictionary_size() { return TreeChunk<Metablock, FreeList<Metablock> >::min_size(); } 342 void print_on(outputStream* st) const; 343 }; 344 345 // A VirtualSpaceList node. 346 class VirtualSpaceNode : public CHeapObj<mtClass> { 347 friend class VirtualSpaceList; 348 349 // Link to next VirtualSpaceNode 350 VirtualSpaceNode* _next; 351 352 // total in the VirtualSpace 353 MemRegion _reserved; 354 ReservedSpace _rs; 355 VirtualSpace _virtual_space; 356 MetaWord* _top; 357 // count of chunks contained in this VirtualSpace 358 uintx _container_count; 359 360 // Convenience functions to access the _virtual_space 361 char* low() const { return virtual_space()->low(); } 362 char* high() const { return virtual_space()->high(); } 363 364 // The first Metachunk will be allocated at the bottom of the 365 // VirtualSpace 366 Metachunk* first_chunk() { return (Metachunk*) bottom(); } 367 368 // Committed but unused space in the virtual space 369 size_t free_words_in_vs() const; 370 public: 371 372 VirtualSpaceNode(size_t byte_size); 373 VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs), _container_count(0) {} 374 ~VirtualSpaceNode(); 375 376 // Convenience functions for logical bottom and end 377 MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); } 378 MetaWord* end() const { return (MetaWord*) _virtual_space.high(); } 379 380 bool contains(const void* ptr) { return ptr >= low() && ptr < high(); } 381 382 size_t reserved_words() const { return _virtual_space.reserved_size() / BytesPerWord; } 383 size_t committed_words() const { return _virtual_space.actual_committed_size() / BytesPerWord; } 384 385 bool is_pre_committed() const { return _virtual_space.special(); } 386 387 // address of next available space in _virtual_space; 388 // Accessors 389 VirtualSpaceNode* next() { return _next; } 390 void set_next(VirtualSpaceNode* v) { _next = v; } 391 392 void set_reserved(MemRegion const v) { _reserved = v; } 393 void set_top(MetaWord* v) { _top = v; } 394 395 // Accessors 396 MemRegion* reserved() { return &_reserved; } 397 VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; } 398 399 // Returns true if "word_size" is available in the VirtualSpace 400 bool is_available(size_t word_size) { return word_size <= pointer_delta(end(), _top, sizeof(MetaWord)); } 401 402 MetaWord* top() const { return _top; } 403 void inc_top(size_t word_size) { _top += word_size; } 404 405 uintx container_count() { return _container_count; } 406 void inc_container_count(); 407 void dec_container_count(); 408 #ifdef ASSERT 409 uintx container_count_slow(); 410 void verify_container_count(); 411 #endif 412 413 // used and capacity in this single entry in the list 414 size_t used_words_in_vs() const; 415 size_t capacity_words_in_vs() const; 416 417 bool initialize(); 418 419 // get space from the virtual space 420 Metachunk* take_from_committed(size_t chunk_word_size); 421 422 // Allocate a chunk from the virtual space and return it. 423 Metachunk* get_chunk_vs(size_t chunk_word_size); 424 425 // Expands/shrinks the committed space in a virtual space. Delegates 426 // to Virtualspace 427 bool expand_by(size_t min_words, size_t preferred_words); 428 429 // In preparation for deleting this node, remove all the chunks 430 // in the node from any freelist. 431 void purge(ChunkManager* chunk_manager); 432 433 // If an allocation doesn't fit in the current node a new node is created. 434 // Allocate chunks out of the remaining committed space in this node 435 // to avoid wasting that memory. 436 // This always adds up because all the chunk sizes are multiples of 437 // the smallest chunk size. 438 void retire(ChunkManager* chunk_manager); 439 440 #ifdef ASSERT 441 // Debug support 442 void mangle(); 443 #endif 444 445 void print_on(outputStream* st) const; 446 }; 447 448 #define assert_is_ptr_aligned(ptr, alignment) \ 449 assert(is_ptr_aligned(ptr, alignment), \ 450 PTR_FORMAT " is not aligned to " \ 451 SIZE_FORMAT, p2i(ptr), alignment) 452 453 #define assert_is_size_aligned(size, alignment) \ 454 assert(is_size_aligned(size, alignment), \ 455 SIZE_FORMAT " is not aligned to " \ 456 SIZE_FORMAT, size, alignment) 457 458 459 // Decide if large pages should be committed when the memory is reserved. 460 static bool should_commit_large_pages_when_reserving(size_t bytes) { 461 if (UseLargePages && UseLargePagesInMetaspace && !os::can_commit_large_page_memory()) { 462 size_t words = bytes / BytesPerWord; 463 bool is_class = false; // We never reserve large pages for the class space. 464 if (MetaspaceGC::can_expand(words, is_class) && 465 MetaspaceGC::allowed_expansion() >= words) { 466 return true; 467 } 468 } 469 470 return false; 471 } 472 473 // byte_size is the size of the associated virtualspace. 474 VirtualSpaceNode::VirtualSpaceNode(size_t bytes) : _top(NULL), _next(NULL), _rs(), _container_count(0) { 475 assert_is_size_aligned(bytes, Metaspace::reserve_alignment()); 476 477 #if INCLUDE_CDS 478 // This allocates memory with mmap. For DumpSharedspaces, try to reserve 479 // configurable address, generally at the top of the Java heap so other 480 // memory addresses don't conflict. 481 if (DumpSharedSpaces) { 482 bool large_pages = false; // No large pages when dumping the CDS archive. 483 char* shared_base = (char*)align_ptr_up((char*)SharedBaseAddress, Metaspace::reserve_alignment()); 484 485 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages, shared_base); 486 if (_rs.is_reserved()) { 487 assert(shared_base == 0 || _rs.base() == shared_base, "should match"); 488 } else { 489 // Get a mmap region anywhere if the SharedBaseAddress fails. 490 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages); 491 } 492 MetaspaceShared::initialize_shared_rs(&_rs); 493 } else 494 #endif 495 { 496 bool large_pages = should_commit_large_pages_when_reserving(bytes); 497 498 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages); 499 } 500 501 if (_rs.is_reserved()) { 502 assert(_rs.base() != NULL, "Catch if we get a NULL address"); 503 assert(_rs.size() != 0, "Catch if we get a 0 size"); 504 assert_is_ptr_aligned(_rs.base(), Metaspace::reserve_alignment()); 505 assert_is_size_aligned(_rs.size(), Metaspace::reserve_alignment()); 506 507 MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass); 508 } 509 } 510 511 void VirtualSpaceNode::purge(ChunkManager* chunk_manager) { 512 Metachunk* chunk = first_chunk(); 513 Metachunk* invalid_chunk = (Metachunk*) top(); 514 while (chunk < invalid_chunk ) { 515 assert(chunk->is_tagged_free(), "Should be tagged free"); 516 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 517 chunk_manager->remove_chunk(chunk); 518 assert(chunk->next() == NULL && 519 chunk->prev() == NULL, 520 "Was not removed from its list"); 521 chunk = (Metachunk*) next; 522 } 523 } 524 525 #ifdef ASSERT 526 uintx VirtualSpaceNode::container_count_slow() { 527 uintx count = 0; 528 Metachunk* chunk = first_chunk(); 529 Metachunk* invalid_chunk = (Metachunk*) top(); 530 while (chunk < invalid_chunk ) { 531 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 532 // Don't count the chunks on the free lists. Those are 533 // still part of the VirtualSpaceNode but not currently 534 // counted. 535 if (!chunk->is_tagged_free()) { 536 count++; 537 } 538 chunk = (Metachunk*) next; 539 } 540 return count; 541 } 542 #endif 543 544 // List of VirtualSpaces for metadata allocation. 545 class VirtualSpaceList : public CHeapObj<mtClass> { 546 friend class VirtualSpaceNode; 547 548 enum VirtualSpaceSizes { 549 VirtualSpaceSize = 256 * K 550 }; 551 552 // Head of the list 553 VirtualSpaceNode* _virtual_space_list; 554 // virtual space currently being used for allocations 555 VirtualSpaceNode* _current_virtual_space; 556 557 // Is this VirtualSpaceList used for the compressed class space 558 bool _is_class; 559 560 // Sum of reserved and committed memory in the virtual spaces 561 size_t _reserved_words; 562 size_t _committed_words; 563 564 // Number of virtual spaces 565 size_t _virtual_space_count; 566 567 ~VirtualSpaceList(); 568 569 VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; } 570 571 void set_virtual_space_list(VirtualSpaceNode* v) { 572 _virtual_space_list = v; 573 } 574 void set_current_virtual_space(VirtualSpaceNode* v) { 575 _current_virtual_space = v; 576 } 577 578 void link_vs(VirtualSpaceNode* new_entry); 579 580 // Get another virtual space and add it to the list. This 581 // is typically prompted by a failed attempt to allocate a chunk 582 // and is typically followed by the allocation of a chunk. 583 bool create_new_virtual_space(size_t vs_word_size); 584 585 // Chunk up the unused committed space in the current 586 // virtual space and add the chunks to the free list. 587 void retire_current_virtual_space(); 588 589 public: 590 VirtualSpaceList(size_t word_size); 591 VirtualSpaceList(ReservedSpace rs); 592 593 size_t free_bytes(); 594 595 Metachunk* get_new_chunk(size_t word_size, 596 size_t grow_chunks_by_words, 597 size_t medium_chunk_bunch); 598 599 bool expand_node_by(VirtualSpaceNode* node, 600 size_t min_words, 601 size_t preferred_words); 602 603 bool expand_by(size_t min_words, 604 size_t preferred_words); 605 606 VirtualSpaceNode* current_virtual_space() { 607 return _current_virtual_space; 608 } 609 610 bool is_class() const { return _is_class; } 611 612 bool initialization_succeeded() { return _virtual_space_list != NULL; } 613 614 size_t reserved_words() { return _reserved_words; } 615 size_t reserved_bytes() { return reserved_words() * BytesPerWord; } 616 size_t committed_words() { return _committed_words; } 617 size_t committed_bytes() { return committed_words() * BytesPerWord; } 618 619 void inc_reserved_words(size_t v); 620 void dec_reserved_words(size_t v); 621 void inc_committed_words(size_t v); 622 void dec_committed_words(size_t v); 623 void inc_virtual_space_count(); 624 void dec_virtual_space_count(); 625 626 bool contains(const void* ptr); 627 628 // Unlink empty VirtualSpaceNodes and free it. 629 void purge(ChunkManager* chunk_manager); 630 631 void print_on(outputStream* st) const; 632 633 class VirtualSpaceListIterator : public StackObj { 634 VirtualSpaceNode* _virtual_spaces; 635 public: 636 VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) : 637 _virtual_spaces(virtual_spaces) {} 638 639 bool repeat() { 640 return _virtual_spaces != NULL; 641 } 642 643 VirtualSpaceNode* get_next() { 644 VirtualSpaceNode* result = _virtual_spaces; 645 if (_virtual_spaces != NULL) { 646 _virtual_spaces = _virtual_spaces->next(); 647 } 648 return result; 649 } 650 }; 651 }; 652 653 class Metadebug : AllStatic { 654 // Debugging support for Metaspaces 655 static int _allocation_fail_alot_count; 656 657 public: 658 659 static void init_allocation_fail_alot_count(); 660 #ifdef ASSERT 661 static bool test_metadata_failure(); 662 #endif 663 }; 664 665 int Metadebug::_allocation_fail_alot_count = 0; 666 667 // SpaceManager - used by Metaspace to handle allocations 668 class SpaceManager : public CHeapObj<mtClass> { 669 friend class Metaspace; 670 friend class Metadebug; 671 672 private: 673 674 // protects allocations 675 Mutex* const _lock; 676 677 // Type of metadata allocated. 678 Metaspace::MetadataType _mdtype; 679 680 // List of chunks in use by this SpaceManager. Allocations 681 // are done from the current chunk. The list is used for deallocating 682 // chunks when the SpaceManager is freed. 683 Metachunk* _chunks_in_use[NumberOfInUseLists]; 684 Metachunk* _current_chunk; 685 686 // Maximum number of small chunks to allocate to a SpaceManager 687 static uint const _small_chunk_limit; 688 689 // Sum of all space in allocated chunks 690 size_t _allocated_blocks_words; 691 692 // Sum of all allocated chunks 693 size_t _allocated_chunks_words; 694 size_t _allocated_chunks_count; 695 696 // Free lists of blocks are per SpaceManager since they 697 // are assumed to be in chunks in use by the SpaceManager 698 // and all chunks in use by a SpaceManager are freed when 699 // the class loader using the SpaceManager is collected. 700 BlockFreelist* _block_freelists; 701 702 // protects virtualspace and chunk expansions 703 static const char* _expand_lock_name; 704 static const int _expand_lock_rank; 705 static Mutex* const _expand_lock; 706 707 private: 708 // Accessors 709 Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; } 710 void set_chunks_in_use(ChunkIndex index, Metachunk* v) { 711 _chunks_in_use[index] = v; 712 } 713 714 BlockFreelist* block_freelists() const { return _block_freelists; } 715 716 Metaspace::MetadataType mdtype() { return _mdtype; } 717 718 VirtualSpaceList* vs_list() const { return Metaspace::get_space_list(_mdtype); } 719 ChunkManager* chunk_manager() const { return Metaspace::get_chunk_manager(_mdtype); } 720 721 Metachunk* current_chunk() const { return _current_chunk; } 722 void set_current_chunk(Metachunk* v) { 723 _current_chunk = v; 724 } 725 726 Metachunk* find_current_chunk(size_t word_size); 727 728 // Add chunk to the list of chunks in use 729 void add_chunk(Metachunk* v, bool make_current); 730 void retire_current_chunk(); 731 732 Mutex* lock() const { return _lock; } 733 734 const char* chunk_size_name(ChunkIndex index) const; 735 736 protected: 737 void initialize(); 738 739 public: 740 SpaceManager(Metaspace::MetadataType mdtype, 741 Mutex* lock); 742 ~SpaceManager(); 743 744 enum ChunkMultiples { 745 MediumChunkMultiple = 4 746 }; 747 748 bool is_class() { return _mdtype == Metaspace::ClassType; } 749 750 // Accessors 751 size_t specialized_chunk_size() { return (size_t) is_class() ? ClassSpecializedChunk : SpecializedChunk; } 752 size_t small_chunk_size() { return (size_t) is_class() ? ClassSmallChunk : SmallChunk; } 753 size_t medium_chunk_size() { return (size_t) is_class() ? ClassMediumChunk : MediumChunk; } 754 size_t medium_chunk_bunch() { return medium_chunk_size() * MediumChunkMultiple; } 755 756 size_t smallest_chunk_size() { return specialized_chunk_size(); } 757 758 size_t allocated_blocks_words() const { return _allocated_blocks_words; } 759 size_t allocated_blocks_bytes() const { return _allocated_blocks_words * BytesPerWord; } 760 size_t allocated_chunks_words() const { return _allocated_chunks_words; } 761 size_t allocated_chunks_bytes() const { return _allocated_chunks_words * BytesPerWord; } 762 size_t allocated_chunks_count() const { return _allocated_chunks_count; } 763 764 bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); } 765 766 static Mutex* expand_lock() { return _expand_lock; } 767 768 // Increment the per Metaspace and global running sums for Metachunks 769 // by the given size. This is used when a Metachunk to added to 770 // the in-use list. 771 void inc_size_metrics(size_t words); 772 // Increment the per Metaspace and global running sums Metablocks by the given 773 // size. This is used when a Metablock is allocated. 774 void inc_used_metrics(size_t words); 775 // Delete the portion of the running sums for this SpaceManager. That is, 776 // the globals running sums for the Metachunks and Metablocks are 777 // decremented for all the Metachunks in-use by this SpaceManager. 778 void dec_total_from_size_metrics(); 779 780 // Set the sizes for the initial chunks. 781 void get_initial_chunk_sizes(Metaspace::MetaspaceType type, 782 size_t* chunk_word_size, 783 size_t* class_chunk_word_size); 784 785 size_t sum_capacity_in_chunks_in_use() const; 786 size_t sum_used_in_chunks_in_use() const; 787 size_t sum_free_in_chunks_in_use() const; 788 size_t sum_waste_in_chunks_in_use() const; 789 size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const; 790 791 size_t sum_count_in_chunks_in_use(); 792 size_t sum_count_in_chunks_in_use(ChunkIndex i); 793 794 Metachunk* get_new_chunk(size_t word_size, size_t grow_chunks_by_words); 795 796 // Block allocation and deallocation. 797 // Allocates a block from the current chunk 798 MetaWord* allocate(size_t word_size); 799 // Allocates a block from a small chunk 800 MetaWord* get_small_chunk_and_allocate(size_t word_size); 801 802 // Helper for allocations 803 MetaWord* allocate_work(size_t word_size); 804 805 // Returns a block to the per manager freelist 806 void deallocate(MetaWord* p, size_t word_size); 807 808 // Based on the allocation size and a minimum chunk size, 809 // returned chunk size (for expanding space for chunk allocation). 810 size_t calc_chunk_size(size_t allocation_word_size); 811 812 // Called when an allocation from the current chunk fails. 813 // Gets a new chunk (may require getting a new virtual space), 814 // and allocates from that chunk. 815 MetaWord* grow_and_allocate(size_t word_size); 816 817 // Notify memory usage to MemoryService. 818 void track_metaspace_memory_usage(); 819 820 // debugging support. 821 822 void dump(outputStream* const out) const; 823 void print_on(outputStream* st) const; 824 void locked_print_chunks_in_use_on(outputStream* st) const; 825 826 void verify(); 827 void verify_chunk_size(Metachunk* chunk); 828 #ifdef ASSERT 829 void verify_allocated_blocks_words(); 830 #endif 831 832 // This adjusts the size given to be greater than the minimum allocation size in 833 // words for data in metaspace. Esentially the minimum size is currently 3 words. 834 size_t get_allocation_word_size(size_t word_size) { 835 size_t byte_size = word_size * BytesPerWord; 836 837 size_t raw_bytes_size = MAX2(byte_size, sizeof(Metablock)); 838 raw_bytes_size = align_size_up(raw_bytes_size, Metachunk::object_alignment()); 839 840 size_t raw_word_size = raw_bytes_size / BytesPerWord; 841 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem"); 842 843 return raw_word_size; 844 } 845 }; 846 847 uint const SpaceManager::_small_chunk_limit = 4; 848 849 const char* SpaceManager::_expand_lock_name = 850 "SpaceManager chunk allocation lock"; 851 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1; 852 Mutex* const SpaceManager::_expand_lock = 853 new Mutex(SpaceManager::_expand_lock_rank, 854 SpaceManager::_expand_lock_name, 855 Mutex::_allow_vm_block_flag, 856 Monitor::_safepoint_check_never); 857 858 void VirtualSpaceNode::inc_container_count() { 859 assert_lock_strong(SpaceManager::expand_lock()); 860 _container_count++; 861 } 862 863 void VirtualSpaceNode::dec_container_count() { 864 assert_lock_strong(SpaceManager::expand_lock()); 865 _container_count--; 866 } 867 868 #ifdef ASSERT 869 void VirtualSpaceNode::verify_container_count() { 870 assert(_container_count == container_count_slow(), 871 "Inconsistency in container_count _container_count " UINTX_FORMAT 872 " container_count_slow() " UINTX_FORMAT, _container_count, container_count_slow()); 873 } 874 #endif 875 876 // BlockFreelist methods 877 878 BlockFreelist::BlockFreelist() : _dictionary(new BlockTreeDictionary()), _small_blocks(NULL) {} 879 880 BlockFreelist::~BlockFreelist() { 881 delete _dictionary; 882 if (_small_blocks != NULL) { 883 delete _small_blocks; 884 } 885 } 886 887 void BlockFreelist::return_block(MetaWord* p, size_t word_size) { 888 assert(word_size >= SmallBlocks::small_block_min_size(), "never return dark matter"); 889 890 Metablock* free_chunk = ::new (p) Metablock(word_size); 891 if (word_size < SmallBlocks::small_block_max_size()) { 892 small_blocks()->return_block(free_chunk, word_size); 893 } else { 894 dictionary()->return_chunk(free_chunk); 895 } 896 log_trace(gc, metaspace, freelist, blocks)("returning block at " INTPTR_FORMAT " size = " 897 SIZE_FORMAT, p2i(free_chunk), word_size); 898 } 899 900 MetaWord* BlockFreelist::get_block(size_t word_size) { 901 assert(word_size >= SmallBlocks::small_block_min_size(), "never get dark matter"); 902 903 // Try small_blocks first. 904 if (word_size < SmallBlocks::small_block_max_size()) { 905 // Don't create small_blocks() until needed. small_blocks() allocates the small block list for 906 // this space manager. 907 MetaWord* new_block = (MetaWord*) small_blocks()->get_block(word_size); 908 if (new_block != NULL) { 909 log_trace(gc, metaspace, freelist, blocks)("getting block at " INTPTR_FORMAT " size = " SIZE_FORMAT, 910 p2i(new_block), word_size); 911 return new_block; 912 } 913 } 914 915 if (word_size < BlockFreelist::min_dictionary_size()) { 916 // If allocation in small blocks fails, this is Dark Matter. Too small for dictionary. 917 return NULL; 918 } 919 920 Metablock* free_block = 921 dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::atLeast); 922 if (free_block == NULL) { 923 return NULL; 924 } 925 926 const size_t block_size = free_block->size(); 927 if (block_size > WasteMultiplier * word_size) { 928 return_block((MetaWord*)free_block, block_size); 929 return NULL; 930 } 931 932 MetaWord* new_block = (MetaWord*)free_block; 933 assert(block_size >= word_size, "Incorrect size of block from freelist"); 934 const size_t unused = block_size - word_size; 935 if (unused >= SmallBlocks::small_block_min_size()) { 936 return_block(new_block + word_size, unused); 937 } 938 939 log_trace(gc, metaspace, freelist, blocks)("getting block at " INTPTR_FORMAT " size = " SIZE_FORMAT, 940 p2i(new_block), word_size); 941 return new_block; 942 } 943 944 void BlockFreelist::print_on(outputStream* st) const { 945 dictionary()->print_free_lists(st); 946 if (_small_blocks != NULL) { 947 _small_blocks->print_on(st); 948 } 949 } 950 951 // VirtualSpaceNode methods 952 953 VirtualSpaceNode::~VirtualSpaceNode() { 954 _rs.release(); 955 #ifdef ASSERT 956 size_t word_size = sizeof(*this) / BytesPerWord; 957 Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1); 958 #endif 959 } 960 961 size_t VirtualSpaceNode::used_words_in_vs() const { 962 return pointer_delta(top(), bottom(), sizeof(MetaWord)); 963 } 964 965 // Space committed in the VirtualSpace 966 size_t VirtualSpaceNode::capacity_words_in_vs() const { 967 return pointer_delta(end(), bottom(), sizeof(MetaWord)); 968 } 969 970 size_t VirtualSpaceNode::free_words_in_vs() const { 971 return pointer_delta(end(), top(), sizeof(MetaWord)); 972 } 973 974 // Allocates the chunk from the virtual space only. 975 // This interface is also used internally for debugging. Not all 976 // chunks removed here are necessarily used for allocation. 977 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) { 978 // Bottom of the new chunk 979 MetaWord* chunk_limit = top(); 980 assert(chunk_limit != NULL, "Not safe to call this method"); 981 982 // The virtual spaces are always expanded by the 983 // commit granularity to enforce the following condition. 984 // Without this the is_available check will not work correctly. 985 assert(_virtual_space.committed_size() == _virtual_space.actual_committed_size(), 986 "The committed memory doesn't match the expanded memory."); 987 988 if (!is_available(chunk_word_size)) { 989 Log(gc, metaspace, freelist) log; 990 log.debug("VirtualSpaceNode::take_from_committed() not available " SIZE_FORMAT " words ", chunk_word_size); 991 // Dump some information about the virtual space that is nearly full 992 ResourceMark rm; 993 print_on(log.debug_stream()); 994 return NULL; 995 } 996 997 // Take the space (bump top on the current virtual space). 998 inc_top(chunk_word_size); 999 1000 // Initialize the chunk 1001 Metachunk* result = ::new (chunk_limit) Metachunk(chunk_word_size, this); 1002 return result; 1003 } 1004 1005 1006 // Expand the virtual space (commit more of the reserved space) 1007 bool VirtualSpaceNode::expand_by(size_t min_words, size_t preferred_words) { 1008 size_t min_bytes = min_words * BytesPerWord; 1009 size_t preferred_bytes = preferred_words * BytesPerWord; 1010 1011 size_t uncommitted = virtual_space()->reserved_size() - virtual_space()->actual_committed_size(); 1012 1013 if (uncommitted < min_bytes) { 1014 return false; 1015 } 1016 1017 size_t commit = MIN2(preferred_bytes, uncommitted); 1018 bool result = virtual_space()->expand_by(commit, false); 1019 1020 assert(result, "Failed to commit memory"); 1021 1022 return result; 1023 } 1024 1025 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) { 1026 assert_lock_strong(SpaceManager::expand_lock()); 1027 Metachunk* result = take_from_committed(chunk_word_size); 1028 if (result != NULL) { 1029 inc_container_count(); 1030 } 1031 return result; 1032 } 1033 1034 bool VirtualSpaceNode::initialize() { 1035 1036 if (!_rs.is_reserved()) { 1037 return false; 1038 } 1039 1040 // These are necessary restriction to make sure that the virtual space always 1041 // grows in steps of Metaspace::commit_alignment(). If both base and size are 1042 // aligned only the middle alignment of the VirtualSpace is used. 1043 assert_is_ptr_aligned(_rs.base(), Metaspace::commit_alignment()); 1044 assert_is_size_aligned(_rs.size(), Metaspace::commit_alignment()); 1045 1046 // ReservedSpaces marked as special will have the entire memory 1047 // pre-committed. Setting a committed size will make sure that 1048 // committed_size and actual_committed_size agrees. 1049 size_t pre_committed_size = _rs.special() ? _rs.size() : 0; 1050 1051 bool result = virtual_space()->initialize_with_granularity(_rs, pre_committed_size, 1052 Metaspace::commit_alignment()); 1053 if (result) { 1054 assert(virtual_space()->committed_size() == virtual_space()->actual_committed_size(), 1055 "Checking that the pre-committed memory was registered by the VirtualSpace"); 1056 1057 set_top((MetaWord*)virtual_space()->low()); 1058 set_reserved(MemRegion((HeapWord*)_rs.base(), 1059 (HeapWord*)(_rs.base() + _rs.size()))); 1060 1061 assert(reserved()->start() == (HeapWord*) _rs.base(), 1062 "Reserved start was not set properly " PTR_FORMAT 1063 " != " PTR_FORMAT, p2i(reserved()->start()), p2i(_rs.base())); 1064 assert(reserved()->word_size() == _rs.size() / BytesPerWord, 1065 "Reserved size was not set properly " SIZE_FORMAT 1066 " != " SIZE_FORMAT, reserved()->word_size(), 1067 _rs.size() / BytesPerWord); 1068 } 1069 1070 return result; 1071 } 1072 1073 void VirtualSpaceNode::print_on(outputStream* st) const { 1074 size_t used = used_words_in_vs(); 1075 size_t capacity = capacity_words_in_vs(); 1076 VirtualSpace* vs = virtual_space(); 1077 st->print_cr(" space @ " PTR_FORMAT " " SIZE_FORMAT "K, " SIZE_FORMAT_W(3) "%% used " 1078 "[" PTR_FORMAT ", " PTR_FORMAT ", " 1079 PTR_FORMAT ", " PTR_FORMAT ")", 1080 p2i(vs), capacity / K, 1081 capacity == 0 ? 0 : used * 100 / capacity, 1082 p2i(bottom()), p2i(top()), p2i(end()), 1083 p2i(vs->high_boundary())); 1084 } 1085 1086 #ifdef ASSERT 1087 void VirtualSpaceNode::mangle() { 1088 size_t word_size = capacity_words_in_vs(); 1089 Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1); 1090 } 1091 #endif // ASSERT 1092 1093 // VirtualSpaceList methods 1094 // Space allocated from the VirtualSpace 1095 1096 VirtualSpaceList::~VirtualSpaceList() { 1097 VirtualSpaceListIterator iter(virtual_space_list()); 1098 while (iter.repeat()) { 1099 VirtualSpaceNode* vsl = iter.get_next(); 1100 delete vsl; 1101 } 1102 } 1103 1104 void VirtualSpaceList::inc_reserved_words(size_t v) { 1105 assert_lock_strong(SpaceManager::expand_lock()); 1106 _reserved_words = _reserved_words + v; 1107 } 1108 void VirtualSpaceList::dec_reserved_words(size_t v) { 1109 assert_lock_strong(SpaceManager::expand_lock()); 1110 _reserved_words = _reserved_words - v; 1111 } 1112 1113 #define assert_committed_below_limit() \ 1114 assert(MetaspaceAux::committed_bytes() <= MaxMetaspaceSize, \ 1115 "Too much committed memory. Committed: " SIZE_FORMAT \ 1116 " limit (MaxMetaspaceSize): " SIZE_FORMAT, \ 1117 MetaspaceAux::committed_bytes(), MaxMetaspaceSize); 1118 1119 void VirtualSpaceList::inc_committed_words(size_t v) { 1120 assert_lock_strong(SpaceManager::expand_lock()); 1121 _committed_words = _committed_words + v; 1122 1123 assert_committed_below_limit(); 1124 } 1125 void VirtualSpaceList::dec_committed_words(size_t v) { 1126 assert_lock_strong(SpaceManager::expand_lock()); 1127 _committed_words = _committed_words - v; 1128 1129 assert_committed_below_limit(); 1130 } 1131 1132 void VirtualSpaceList::inc_virtual_space_count() { 1133 assert_lock_strong(SpaceManager::expand_lock()); 1134 _virtual_space_count++; 1135 } 1136 void VirtualSpaceList::dec_virtual_space_count() { 1137 assert_lock_strong(SpaceManager::expand_lock()); 1138 _virtual_space_count--; 1139 } 1140 1141 void ChunkManager::remove_chunk(Metachunk* chunk) { 1142 size_t word_size = chunk->word_size(); 1143 ChunkIndex index = list_index(word_size); 1144 if (index != HumongousIndex) { 1145 free_chunks(index)->remove_chunk(chunk); 1146 } else { 1147 humongous_dictionary()->remove_chunk(chunk); 1148 } 1149 1150 // Chunk is being removed from the chunks free list. 1151 dec_free_chunks_total(chunk->word_size()); 1152 } 1153 1154 // Walk the list of VirtualSpaceNodes and delete 1155 // nodes with a 0 container_count. Remove Metachunks in 1156 // the node from their respective freelists. 1157 void VirtualSpaceList::purge(ChunkManager* chunk_manager) { 1158 assert(SafepointSynchronize::is_at_safepoint(), "must be called at safepoint for contains to work"); 1159 assert_lock_strong(SpaceManager::expand_lock()); 1160 // Don't use a VirtualSpaceListIterator because this 1161 // list is being changed and a straightforward use of an iterator is not safe. 1162 VirtualSpaceNode* purged_vsl = NULL; 1163 VirtualSpaceNode* prev_vsl = virtual_space_list(); 1164 VirtualSpaceNode* next_vsl = prev_vsl; 1165 while (next_vsl != NULL) { 1166 VirtualSpaceNode* vsl = next_vsl; 1167 DEBUG_ONLY(vsl->verify_container_count();) 1168 next_vsl = vsl->next(); 1169 // Don't free the current virtual space since it will likely 1170 // be needed soon. 1171 if (vsl->container_count() == 0 && vsl != current_virtual_space()) { 1172 // Unlink it from the list 1173 if (prev_vsl == vsl) { 1174 // This is the case of the current node being the first node. 1175 assert(vsl == virtual_space_list(), "Expected to be the first node"); 1176 set_virtual_space_list(vsl->next()); 1177 } else { 1178 prev_vsl->set_next(vsl->next()); 1179 } 1180 1181 vsl->purge(chunk_manager); 1182 dec_reserved_words(vsl->reserved_words()); 1183 dec_committed_words(vsl->committed_words()); 1184 dec_virtual_space_count(); 1185 purged_vsl = vsl; 1186 delete vsl; 1187 } else { 1188 prev_vsl = vsl; 1189 } 1190 } 1191 #ifdef ASSERT 1192 if (purged_vsl != NULL) { 1193 // List should be stable enough to use an iterator here. 1194 VirtualSpaceListIterator iter(virtual_space_list()); 1195 while (iter.repeat()) { 1196 VirtualSpaceNode* vsl = iter.get_next(); 1197 assert(vsl != purged_vsl, "Purge of vsl failed"); 1198 } 1199 } 1200 #endif 1201 } 1202 1203 1204 // This function looks at the mmap regions in the metaspace without locking. 1205 // The chunks are added with store ordering and not deleted except for at 1206 // unloading time during a safepoint. 1207 bool VirtualSpaceList::contains(const void* ptr) { 1208 // List should be stable enough to use an iterator here because removing virtual 1209 // space nodes is only allowed at a safepoint. 1210 VirtualSpaceListIterator iter(virtual_space_list()); 1211 while (iter.repeat()) { 1212 VirtualSpaceNode* vsn = iter.get_next(); 1213 if (vsn->contains(ptr)) { 1214 return true; 1215 } 1216 } 1217 return false; 1218 } 1219 1220 void VirtualSpaceList::retire_current_virtual_space() { 1221 assert_lock_strong(SpaceManager::expand_lock()); 1222 1223 VirtualSpaceNode* vsn = current_virtual_space(); 1224 1225 ChunkManager* cm = is_class() ? Metaspace::chunk_manager_class() : 1226 Metaspace::chunk_manager_metadata(); 1227 1228 vsn->retire(cm); 1229 } 1230 1231 void VirtualSpaceNode::retire(ChunkManager* chunk_manager) { 1232 DEBUG_ONLY(verify_container_count();) 1233 for (int i = (int)MediumIndex; i >= (int)ZeroIndex; --i) { 1234 ChunkIndex index = (ChunkIndex)i; 1235 size_t chunk_size = chunk_manager->free_chunks(index)->size(); 1236 1237 while (free_words_in_vs() >= chunk_size) { 1238 Metachunk* chunk = get_chunk_vs(chunk_size); 1239 assert(chunk != NULL, "allocation should have been successful"); 1240 1241 chunk_manager->return_chunks(index, chunk); 1242 chunk_manager->inc_free_chunks_total(chunk_size); 1243 } 1244 DEBUG_ONLY(verify_container_count();) 1245 } 1246 assert(free_words_in_vs() == 0, "should be empty now"); 1247 } 1248 1249 VirtualSpaceList::VirtualSpaceList(size_t word_size) : 1250 _is_class(false), 1251 _virtual_space_list(NULL), 1252 _current_virtual_space(NULL), 1253 _reserved_words(0), 1254 _committed_words(0), 1255 _virtual_space_count(0) { 1256 MutexLockerEx cl(SpaceManager::expand_lock(), 1257 Mutex::_no_safepoint_check_flag); 1258 create_new_virtual_space(word_size); 1259 } 1260 1261 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) : 1262 _is_class(true), 1263 _virtual_space_list(NULL), 1264 _current_virtual_space(NULL), 1265 _reserved_words(0), 1266 _committed_words(0), 1267 _virtual_space_count(0) { 1268 MutexLockerEx cl(SpaceManager::expand_lock(), 1269 Mutex::_no_safepoint_check_flag); 1270 VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs); 1271 bool succeeded = class_entry->initialize(); 1272 if (succeeded) { 1273 link_vs(class_entry); 1274 } 1275 } 1276 1277 size_t VirtualSpaceList::free_bytes() { 1278 return virtual_space_list()->free_words_in_vs() * BytesPerWord; 1279 } 1280 1281 // Allocate another meta virtual space and add it to the list. 1282 bool VirtualSpaceList::create_new_virtual_space(size_t vs_word_size) { 1283 assert_lock_strong(SpaceManager::expand_lock()); 1284 1285 if (is_class()) { 1286 assert(false, "We currently don't support more than one VirtualSpace for" 1287 " the compressed class space. The initialization of the" 1288 " CCS uses another code path and should not hit this path."); 1289 return false; 1290 } 1291 1292 if (vs_word_size == 0) { 1293 assert(false, "vs_word_size should always be at least _reserve_alignment large."); 1294 return false; 1295 } 1296 1297 // Reserve the space 1298 size_t vs_byte_size = vs_word_size * BytesPerWord; 1299 assert_is_size_aligned(vs_byte_size, Metaspace::reserve_alignment()); 1300 1301 // Allocate the meta virtual space and initialize it. 1302 VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size); 1303 if (!new_entry->initialize()) { 1304 delete new_entry; 1305 return false; 1306 } else { 1307 assert(new_entry->reserved_words() == vs_word_size, 1308 "Reserved memory size differs from requested memory size"); 1309 // ensure lock-free iteration sees fully initialized node 1310 OrderAccess::storestore(); 1311 link_vs(new_entry); 1312 return true; 1313 } 1314 } 1315 1316 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry) { 1317 if (virtual_space_list() == NULL) { 1318 set_virtual_space_list(new_entry); 1319 } else { 1320 current_virtual_space()->set_next(new_entry); 1321 } 1322 set_current_virtual_space(new_entry); 1323 inc_reserved_words(new_entry->reserved_words()); 1324 inc_committed_words(new_entry->committed_words()); 1325 inc_virtual_space_count(); 1326 #ifdef ASSERT 1327 new_entry->mangle(); 1328 #endif 1329 if (log_is_enabled(Trace, gc, metaspace)) { 1330 Log(gc, metaspace) log; 1331 VirtualSpaceNode* vsl = current_virtual_space(); 1332 ResourceMark rm; 1333 vsl->print_on(log.trace_stream()); 1334 } 1335 } 1336 1337 bool VirtualSpaceList::expand_node_by(VirtualSpaceNode* node, 1338 size_t min_words, 1339 size_t preferred_words) { 1340 size_t before = node->committed_words(); 1341 1342 bool result = node->expand_by(min_words, preferred_words); 1343 1344 size_t after = node->committed_words(); 1345 1346 // after and before can be the same if the memory was pre-committed. 1347 assert(after >= before, "Inconsistency"); 1348 inc_committed_words(after - before); 1349 1350 return result; 1351 } 1352 1353 bool VirtualSpaceList::expand_by(size_t min_words, size_t preferred_words) { 1354 assert_is_size_aligned(min_words, Metaspace::commit_alignment_words()); 1355 assert_is_size_aligned(preferred_words, Metaspace::commit_alignment_words()); 1356 assert(min_words <= preferred_words, "Invalid arguments"); 1357 1358 if (!MetaspaceGC::can_expand(min_words, this->is_class())) { 1359 return false; 1360 } 1361 1362 size_t allowed_expansion_words = MetaspaceGC::allowed_expansion(); 1363 if (allowed_expansion_words < min_words) { 1364 return false; 1365 } 1366 1367 size_t max_expansion_words = MIN2(preferred_words, allowed_expansion_words); 1368 1369 // Commit more memory from the the current virtual space. 1370 bool vs_expanded = expand_node_by(current_virtual_space(), 1371 min_words, 1372 max_expansion_words); 1373 if (vs_expanded) { 1374 return true; 1375 } 1376 retire_current_virtual_space(); 1377 1378 // Get another virtual space. 1379 size_t grow_vs_words = MAX2((size_t)VirtualSpaceSize, preferred_words); 1380 grow_vs_words = align_size_up(grow_vs_words, Metaspace::reserve_alignment_words()); 1381 1382 if (create_new_virtual_space(grow_vs_words)) { 1383 if (current_virtual_space()->is_pre_committed()) { 1384 // The memory was pre-committed, so we are done here. 1385 assert(min_words <= current_virtual_space()->committed_words(), 1386 "The new VirtualSpace was pre-committed, so it" 1387 "should be large enough to fit the alloc request."); 1388 return true; 1389 } 1390 1391 return expand_node_by(current_virtual_space(), 1392 min_words, 1393 max_expansion_words); 1394 } 1395 1396 return false; 1397 } 1398 1399 Metachunk* VirtualSpaceList::get_new_chunk(size_t word_size, 1400 size_t grow_chunks_by_words, 1401 size_t medium_chunk_bunch) { 1402 1403 // Allocate a chunk out of the current virtual space. 1404 Metachunk* next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words); 1405 1406 if (next != NULL) { 1407 return next; 1408 } 1409 1410 // The expand amount is currently only determined by the requested sizes 1411 // and not how much committed memory is left in the current virtual space. 1412 1413 size_t min_word_size = align_size_up(grow_chunks_by_words, Metaspace::commit_alignment_words()); 1414 size_t preferred_word_size = align_size_up(medium_chunk_bunch, Metaspace::commit_alignment_words()); 1415 if (min_word_size >= preferred_word_size) { 1416 // Can happen when humongous chunks are allocated. 1417 preferred_word_size = min_word_size; 1418 } 1419 1420 bool expanded = expand_by(min_word_size, preferred_word_size); 1421 if (expanded) { 1422 next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words); 1423 assert(next != NULL, "The allocation was expected to succeed after the expansion"); 1424 } 1425 1426 return next; 1427 } 1428 1429 void VirtualSpaceList::print_on(outputStream* st) const { 1430 VirtualSpaceListIterator iter(virtual_space_list()); 1431 while (iter.repeat()) { 1432 VirtualSpaceNode* node = iter.get_next(); 1433 node->print_on(st); 1434 } 1435 } 1436 1437 // MetaspaceGC methods 1438 1439 // VM_CollectForMetadataAllocation is the vm operation used to GC. 1440 // Within the VM operation after the GC the attempt to allocate the metadata 1441 // should succeed. If the GC did not free enough space for the metaspace 1442 // allocation, the HWM is increased so that another virtualspace will be 1443 // allocated for the metadata. With perm gen the increase in the perm 1444 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The 1445 // metaspace policy uses those as the small and large steps for the HWM. 1446 // 1447 // After the GC the compute_new_size() for MetaspaceGC is called to 1448 // resize the capacity of the metaspaces. The current implementation 1449 // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used 1450 // to resize the Java heap by some GC's. New flags can be implemented 1451 // if really needed. MinMetaspaceFreeRatio is used to calculate how much 1452 // free space is desirable in the metaspace capacity to decide how much 1453 // to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much 1454 // free space is desirable in the metaspace capacity before decreasing 1455 // the HWM. 1456 1457 // Calculate the amount to increase the high water mark (HWM). 1458 // Increase by a minimum amount (MinMetaspaceExpansion) so that 1459 // another expansion is not requested too soon. If that is not 1460 // enough to satisfy the allocation, increase by MaxMetaspaceExpansion. 1461 // If that is still not enough, expand by the size of the allocation 1462 // plus some. 1463 size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) { 1464 size_t min_delta = MinMetaspaceExpansion; 1465 size_t max_delta = MaxMetaspaceExpansion; 1466 size_t delta = align_size_up(bytes, Metaspace::commit_alignment()); 1467 1468 if (delta <= min_delta) { 1469 delta = min_delta; 1470 } else if (delta <= max_delta) { 1471 // Don't want to hit the high water mark on the next 1472 // allocation so make the delta greater than just enough 1473 // for this allocation. 1474 delta = max_delta; 1475 } else { 1476 // This allocation is large but the next ones are probably not 1477 // so increase by the minimum. 1478 delta = delta + min_delta; 1479 } 1480 1481 assert_is_size_aligned(delta, Metaspace::commit_alignment()); 1482 1483 return delta; 1484 } 1485 1486 size_t MetaspaceGC::capacity_until_GC() { 1487 size_t value = (size_t)OrderAccess::load_ptr_acquire(&_capacity_until_GC); 1488 assert(value >= MetaspaceSize, "Not initialized properly?"); 1489 return value; 1490 } 1491 1492 bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC) { 1493 assert_is_size_aligned(v, Metaspace::commit_alignment()); 1494 1495 size_t capacity_until_GC = (size_t) _capacity_until_GC; 1496 size_t new_value = capacity_until_GC + v; 1497 1498 if (new_value < capacity_until_GC) { 1499 // The addition wrapped around, set new_value to aligned max value. 1500 new_value = align_size_down(max_uintx, Metaspace::commit_alignment()); 1501 } 1502 1503 intptr_t expected = (intptr_t) capacity_until_GC; 1504 intptr_t actual = Atomic::cmpxchg_ptr((intptr_t) new_value, &_capacity_until_GC, expected); 1505 1506 if (expected != actual) { 1507 return false; 1508 } 1509 1510 if (new_cap_until_GC != NULL) { 1511 *new_cap_until_GC = new_value; 1512 } 1513 if (old_cap_until_GC != NULL) { 1514 *old_cap_until_GC = capacity_until_GC; 1515 } 1516 return true; 1517 } 1518 1519 size_t MetaspaceGC::dec_capacity_until_GC(size_t v) { 1520 assert_is_size_aligned(v, Metaspace::commit_alignment()); 1521 1522 return (size_t)Atomic::add_ptr(-(intptr_t)v, &_capacity_until_GC); 1523 } 1524 1525 void MetaspaceGC::initialize() { 1526 // Set the high-water mark to MaxMetapaceSize during VM initializaton since 1527 // we can't do a GC during initialization. 1528 _capacity_until_GC = MaxMetaspaceSize; 1529 } 1530 1531 void MetaspaceGC::post_initialize() { 1532 // Reset the high-water mark once the VM initialization is done. 1533 _capacity_until_GC = MAX2(MetaspaceAux::committed_bytes(), MetaspaceSize); 1534 } 1535 1536 bool MetaspaceGC::can_expand(size_t word_size, bool is_class) { 1537 // Check if the compressed class space is full. 1538 if (is_class && Metaspace::using_class_space()) { 1539 size_t class_committed = MetaspaceAux::committed_bytes(Metaspace::ClassType); 1540 if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) { 1541 return false; 1542 } 1543 } 1544 1545 // Check if the user has imposed a limit on the metaspace memory. 1546 size_t committed_bytes = MetaspaceAux::committed_bytes(); 1547 if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) { 1548 return false; 1549 } 1550 1551 return true; 1552 } 1553 1554 size_t MetaspaceGC::allowed_expansion() { 1555 size_t committed_bytes = MetaspaceAux::committed_bytes(); 1556 size_t capacity_until_gc = capacity_until_GC(); 1557 1558 assert(capacity_until_gc >= committed_bytes, 1559 "capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT, 1560 capacity_until_gc, committed_bytes); 1561 1562 size_t left_until_max = MaxMetaspaceSize - committed_bytes; 1563 size_t left_until_GC = capacity_until_gc - committed_bytes; 1564 size_t left_to_commit = MIN2(left_until_GC, left_until_max); 1565 1566 return left_to_commit / BytesPerWord; 1567 } 1568 1569 void MetaspaceGC::compute_new_size() { 1570 assert(_shrink_factor <= 100, "invalid shrink factor"); 1571 uint current_shrink_factor = _shrink_factor; 1572 _shrink_factor = 0; 1573 1574 // Using committed_bytes() for used_after_gc is an overestimation, since the 1575 // chunk free lists are included in committed_bytes() and the memory in an 1576 // un-fragmented chunk free list is available for future allocations. 1577 // However, if the chunk free lists becomes fragmented, then the memory may 1578 // not be available for future allocations and the memory is therefore "in use". 1579 // Including the chunk free lists in the definition of "in use" is therefore 1580 // necessary. Not including the chunk free lists can cause capacity_until_GC to 1581 // shrink below committed_bytes() and this has caused serious bugs in the past. 1582 const size_t used_after_gc = MetaspaceAux::committed_bytes(); 1583 const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC(); 1584 1585 const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0; 1586 const double maximum_used_percentage = 1.0 - minimum_free_percentage; 1587 1588 const double min_tmp = used_after_gc / maximum_used_percentage; 1589 size_t minimum_desired_capacity = 1590 (size_t)MIN2(min_tmp, double(max_uintx)); 1591 // Don't shrink less than the initial generation size 1592 minimum_desired_capacity = MAX2(minimum_desired_capacity, 1593 MetaspaceSize); 1594 1595 log_trace(gc, metaspace)("MetaspaceGC::compute_new_size: "); 1596 log_trace(gc, metaspace)(" minimum_free_percentage: %6.2f maximum_used_percentage: %6.2f", 1597 minimum_free_percentage, maximum_used_percentage); 1598 log_trace(gc, metaspace)(" used_after_gc : %6.1fKB", used_after_gc / (double) K); 1599 1600 1601 size_t shrink_bytes = 0; 1602 if (capacity_until_GC < minimum_desired_capacity) { 1603 // If we have less capacity below the metaspace HWM, then 1604 // increment the HWM. 1605 size_t expand_bytes = minimum_desired_capacity - capacity_until_GC; 1606 expand_bytes = align_size_up(expand_bytes, Metaspace::commit_alignment()); 1607 // Don't expand unless it's significant 1608 if (expand_bytes >= MinMetaspaceExpansion) { 1609 size_t new_capacity_until_GC = 0; 1610 bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC); 1611 assert(succeeded, "Should always succesfully increment HWM when at safepoint"); 1612 1613 Metaspace::tracer()->report_gc_threshold(capacity_until_GC, 1614 new_capacity_until_GC, 1615 MetaspaceGCThresholdUpdater::ComputeNewSize); 1616 log_trace(gc, metaspace)(" expanding: minimum_desired_capacity: %6.1fKB expand_bytes: %6.1fKB MinMetaspaceExpansion: %6.1fKB new metaspace HWM: %6.1fKB", 1617 minimum_desired_capacity / (double) K, 1618 expand_bytes / (double) K, 1619 MinMetaspaceExpansion / (double) K, 1620 new_capacity_until_GC / (double) K); 1621 } 1622 return; 1623 } 1624 1625 // No expansion, now see if we want to shrink 1626 // We would never want to shrink more than this 1627 assert(capacity_until_GC >= minimum_desired_capacity, 1628 SIZE_FORMAT " >= " SIZE_FORMAT, 1629 capacity_until_GC, minimum_desired_capacity); 1630 size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity; 1631 1632 // Should shrinking be considered? 1633 if (MaxMetaspaceFreeRatio < 100) { 1634 const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0; 1635 const double minimum_used_percentage = 1.0 - maximum_free_percentage; 1636 const double max_tmp = used_after_gc / minimum_used_percentage; 1637 size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx)); 1638 maximum_desired_capacity = MAX2(maximum_desired_capacity, 1639 MetaspaceSize); 1640 log_trace(gc, metaspace)(" maximum_free_percentage: %6.2f minimum_used_percentage: %6.2f", 1641 maximum_free_percentage, minimum_used_percentage); 1642 log_trace(gc, metaspace)(" minimum_desired_capacity: %6.1fKB maximum_desired_capacity: %6.1fKB", 1643 minimum_desired_capacity / (double) K, maximum_desired_capacity / (double) K); 1644 1645 assert(minimum_desired_capacity <= maximum_desired_capacity, 1646 "sanity check"); 1647 1648 if (capacity_until_GC > maximum_desired_capacity) { 1649 // Capacity too large, compute shrinking size 1650 shrink_bytes = capacity_until_GC - maximum_desired_capacity; 1651 // We don't want shrink all the way back to initSize if people call 1652 // System.gc(), because some programs do that between "phases" and then 1653 // we'd just have to grow the heap up again for the next phase. So we 1654 // damp the shrinking: 0% on the first call, 10% on the second call, 40% 1655 // on the third call, and 100% by the fourth call. But if we recompute 1656 // size without shrinking, it goes back to 0%. 1657 shrink_bytes = shrink_bytes / 100 * current_shrink_factor; 1658 1659 shrink_bytes = align_size_down(shrink_bytes, Metaspace::commit_alignment()); 1660 1661 assert(shrink_bytes <= max_shrink_bytes, 1662 "invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT, 1663 shrink_bytes, max_shrink_bytes); 1664 if (current_shrink_factor == 0) { 1665 _shrink_factor = 10; 1666 } else { 1667 _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100); 1668 } 1669 log_trace(gc, metaspace)(" shrinking: initThreshold: %.1fK maximum_desired_capacity: %.1fK", 1670 MetaspaceSize / (double) K, maximum_desired_capacity / (double) K); 1671 log_trace(gc, metaspace)(" shrink_bytes: %.1fK current_shrink_factor: %d new shrink factor: %d MinMetaspaceExpansion: %.1fK", 1672 shrink_bytes / (double) K, current_shrink_factor, _shrink_factor, MinMetaspaceExpansion / (double) K); 1673 } 1674 } 1675 1676 // Don't shrink unless it's significant 1677 if (shrink_bytes >= MinMetaspaceExpansion && 1678 ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) { 1679 size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes); 1680 Metaspace::tracer()->report_gc_threshold(capacity_until_GC, 1681 new_capacity_until_GC, 1682 MetaspaceGCThresholdUpdater::ComputeNewSize); 1683 } 1684 } 1685 1686 // Metadebug methods 1687 1688 void Metadebug::init_allocation_fail_alot_count() { 1689 if (MetadataAllocationFailALot) { 1690 _allocation_fail_alot_count = 1691 1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0)); 1692 } 1693 } 1694 1695 #ifdef ASSERT 1696 bool Metadebug::test_metadata_failure() { 1697 if (MetadataAllocationFailALot && 1698 Threads::is_vm_complete()) { 1699 if (_allocation_fail_alot_count > 0) { 1700 _allocation_fail_alot_count--; 1701 } else { 1702 log_trace(gc, metaspace, freelist)("Metadata allocation failing for MetadataAllocationFailALot"); 1703 init_allocation_fail_alot_count(); 1704 return true; 1705 } 1706 } 1707 return false; 1708 } 1709 #endif 1710 1711 // ChunkManager methods 1712 1713 size_t ChunkManager::free_chunks_total_words() { 1714 return _free_chunks_total; 1715 } 1716 1717 size_t ChunkManager::free_chunks_total_bytes() { 1718 return free_chunks_total_words() * BytesPerWord; 1719 } 1720 1721 size_t ChunkManager::free_chunks_count() { 1722 #ifdef ASSERT 1723 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) { 1724 MutexLockerEx cl(SpaceManager::expand_lock(), 1725 Mutex::_no_safepoint_check_flag); 1726 // This lock is only needed in debug because the verification 1727 // of the _free_chunks_totals walks the list of free chunks 1728 slow_locked_verify_free_chunks_count(); 1729 } 1730 #endif 1731 return _free_chunks_count; 1732 } 1733 1734 void ChunkManager::locked_verify_free_chunks_total() { 1735 assert_lock_strong(SpaceManager::expand_lock()); 1736 assert(sum_free_chunks() == _free_chunks_total, 1737 "_free_chunks_total " SIZE_FORMAT " is not the" 1738 " same as sum " SIZE_FORMAT, _free_chunks_total, 1739 sum_free_chunks()); 1740 } 1741 1742 void ChunkManager::verify_free_chunks_total() { 1743 MutexLockerEx cl(SpaceManager::expand_lock(), 1744 Mutex::_no_safepoint_check_flag); 1745 locked_verify_free_chunks_total(); 1746 } 1747 1748 void ChunkManager::locked_verify_free_chunks_count() { 1749 assert_lock_strong(SpaceManager::expand_lock()); 1750 assert(sum_free_chunks_count() == _free_chunks_count, 1751 "_free_chunks_count " SIZE_FORMAT " is not the" 1752 " same as sum " SIZE_FORMAT, _free_chunks_count, 1753 sum_free_chunks_count()); 1754 } 1755 1756 void ChunkManager::verify_free_chunks_count() { 1757 #ifdef ASSERT 1758 MutexLockerEx cl(SpaceManager::expand_lock(), 1759 Mutex::_no_safepoint_check_flag); 1760 locked_verify_free_chunks_count(); 1761 #endif 1762 } 1763 1764 void ChunkManager::verify() { 1765 MutexLockerEx cl(SpaceManager::expand_lock(), 1766 Mutex::_no_safepoint_check_flag); 1767 locked_verify(); 1768 } 1769 1770 void ChunkManager::locked_verify() { 1771 locked_verify_free_chunks_count(); 1772 locked_verify_free_chunks_total(); 1773 } 1774 1775 void ChunkManager::locked_print_free_chunks(outputStream* st) { 1776 assert_lock_strong(SpaceManager::expand_lock()); 1777 st->print_cr("Free chunk total " SIZE_FORMAT " count " SIZE_FORMAT, 1778 _free_chunks_total, _free_chunks_count); 1779 } 1780 1781 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) { 1782 assert_lock_strong(SpaceManager::expand_lock()); 1783 st->print_cr("Sum free chunk total " SIZE_FORMAT " count " SIZE_FORMAT, 1784 sum_free_chunks(), sum_free_chunks_count()); 1785 } 1786 ChunkList* ChunkManager::free_chunks(ChunkIndex index) { 1787 return &_free_chunks[index]; 1788 } 1789 1790 // These methods that sum the free chunk lists are used in printing 1791 // methods that are used in product builds. 1792 size_t ChunkManager::sum_free_chunks() { 1793 assert_lock_strong(SpaceManager::expand_lock()); 1794 size_t result = 0; 1795 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 1796 ChunkList* list = free_chunks(i); 1797 1798 if (list == NULL) { 1799 continue; 1800 } 1801 1802 result = result + list->count() * list->size(); 1803 } 1804 result = result + humongous_dictionary()->total_size(); 1805 return result; 1806 } 1807 1808 size_t ChunkManager::sum_free_chunks_count() { 1809 assert_lock_strong(SpaceManager::expand_lock()); 1810 size_t count = 0; 1811 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 1812 ChunkList* list = free_chunks(i); 1813 if (list == NULL) { 1814 continue; 1815 } 1816 count = count + list->count(); 1817 } 1818 count = count + humongous_dictionary()->total_free_blocks(); 1819 return count; 1820 } 1821 1822 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) { 1823 ChunkIndex index = list_index(word_size); 1824 assert(index < HumongousIndex, "No humongous list"); 1825 return free_chunks(index); 1826 } 1827 1828 Metachunk* ChunkManager::free_chunks_get(size_t word_size) { 1829 assert_lock_strong(SpaceManager::expand_lock()); 1830 1831 slow_locked_verify(); 1832 1833 Metachunk* chunk = NULL; 1834 if (list_index(word_size) != HumongousIndex) { 1835 ChunkList* free_list = find_free_chunks_list(word_size); 1836 assert(free_list != NULL, "Sanity check"); 1837 1838 chunk = free_list->head(); 1839 1840 if (chunk == NULL) { 1841 return NULL; 1842 } 1843 1844 // Remove the chunk as the head of the list. 1845 free_list->remove_chunk(chunk); 1846 1847 log_trace(gc, metaspace, freelist)("ChunkManager::free_chunks_get: free_list " PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT, 1848 p2i(free_list), p2i(chunk), chunk->word_size()); 1849 } else { 1850 chunk = humongous_dictionary()->get_chunk( 1851 word_size, 1852 FreeBlockDictionary<Metachunk>::atLeast); 1853 1854 if (chunk == NULL) { 1855 return NULL; 1856 } 1857 1858 log_debug(gc, metaspace, alloc)("Free list allocate humongous chunk size " SIZE_FORMAT " for requested size " SIZE_FORMAT " waste " SIZE_FORMAT, 1859 chunk->word_size(), word_size, chunk->word_size() - word_size); 1860 } 1861 1862 // Chunk is being removed from the chunks free list. 1863 dec_free_chunks_total(chunk->word_size()); 1864 1865 // Remove it from the links to this freelist 1866 chunk->set_next(NULL); 1867 chunk->set_prev(NULL); 1868 #ifdef ASSERT 1869 // Chunk is no longer on any freelist. Setting to false make container_count_slow() 1870 // work. 1871 chunk->set_is_tagged_free(false); 1872 #endif 1873 chunk->container()->inc_container_count(); 1874 1875 slow_locked_verify(); 1876 return chunk; 1877 } 1878 1879 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) { 1880 assert_lock_strong(SpaceManager::expand_lock()); 1881 slow_locked_verify(); 1882 1883 // Take from the beginning of the list 1884 Metachunk* chunk = free_chunks_get(word_size); 1885 if (chunk == NULL) { 1886 return NULL; 1887 } 1888 1889 assert((word_size <= chunk->word_size()) || 1890 list_index(chunk->word_size() == HumongousIndex), 1891 "Non-humongous variable sized chunk"); 1892 Log(gc, metaspace, freelist) log; 1893 if (log.is_debug()) { 1894 size_t list_count; 1895 if (list_index(word_size) < HumongousIndex) { 1896 ChunkList* list = find_free_chunks_list(word_size); 1897 list_count = list->count(); 1898 } else { 1899 list_count = humongous_dictionary()->total_count(); 1900 } 1901 log.debug("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk " PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ", 1902 p2i(this), p2i(chunk), chunk->word_size(), list_count); 1903 ResourceMark rm; 1904 locked_print_free_chunks(log.debug_stream()); 1905 } 1906 1907 return chunk; 1908 } 1909 1910 void ChunkManager::print_on(outputStream* out) const { 1911 const_cast<ChunkManager *>(this)->humongous_dictionary()->report_statistics(out); 1912 } 1913 1914 // SpaceManager methods 1915 1916 void SpaceManager::get_initial_chunk_sizes(Metaspace::MetaspaceType type, 1917 size_t* chunk_word_size, 1918 size_t* class_chunk_word_size) { 1919 switch (type) { 1920 case Metaspace::BootMetaspaceType: 1921 *chunk_word_size = Metaspace::first_chunk_word_size(); 1922 *class_chunk_word_size = Metaspace::first_class_chunk_word_size(); 1923 break; 1924 case Metaspace::ROMetaspaceType: 1925 *chunk_word_size = SharedReadOnlySize / wordSize; 1926 *class_chunk_word_size = ClassSpecializedChunk; 1927 break; 1928 case Metaspace::ReadWriteMetaspaceType: 1929 *chunk_word_size = SharedReadWriteSize / wordSize; 1930 *class_chunk_word_size = ClassSpecializedChunk; 1931 break; 1932 case Metaspace::AnonymousMetaspaceType: 1933 case Metaspace::ReflectionMetaspaceType: 1934 *chunk_word_size = SpecializedChunk; 1935 *class_chunk_word_size = ClassSpecializedChunk; 1936 break; 1937 default: 1938 *chunk_word_size = SmallChunk; 1939 *class_chunk_word_size = ClassSmallChunk; 1940 break; 1941 } 1942 assert(*chunk_word_size != 0 && *class_chunk_word_size != 0, 1943 "Initial chunks sizes bad: data " SIZE_FORMAT 1944 " class " SIZE_FORMAT, 1945 *chunk_word_size, *class_chunk_word_size); 1946 } 1947 1948 size_t SpaceManager::sum_free_in_chunks_in_use() const { 1949 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 1950 size_t free = 0; 1951 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 1952 Metachunk* chunk = chunks_in_use(i); 1953 while (chunk != NULL) { 1954 free += chunk->free_word_size(); 1955 chunk = chunk->next(); 1956 } 1957 } 1958 return free; 1959 } 1960 1961 size_t SpaceManager::sum_waste_in_chunks_in_use() const { 1962 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 1963 size_t result = 0; 1964 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 1965 result += sum_waste_in_chunks_in_use(i); 1966 } 1967 1968 return result; 1969 } 1970 1971 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const { 1972 size_t result = 0; 1973 Metachunk* chunk = chunks_in_use(index); 1974 // Count the free space in all the chunk but not the 1975 // current chunk from which allocations are still being done. 1976 while (chunk != NULL) { 1977 if (chunk != current_chunk()) { 1978 result += chunk->free_word_size(); 1979 } 1980 chunk = chunk->next(); 1981 } 1982 return result; 1983 } 1984 1985 size_t SpaceManager::sum_capacity_in_chunks_in_use() const { 1986 // For CMS use "allocated_chunks_words()" which does not need the 1987 // Metaspace lock. For the other collectors sum over the 1988 // lists. Use both methods as a check that "allocated_chunks_words()" 1989 // is correct. That is, sum_capacity_in_chunks() is too expensive 1990 // to use in the product and allocated_chunks_words() should be used 1991 // but allow for checking that allocated_chunks_words() returns the same 1992 // value as sum_capacity_in_chunks_in_use() which is the definitive 1993 // answer. 1994 if (UseConcMarkSweepGC) { 1995 return allocated_chunks_words(); 1996 } else { 1997 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 1998 size_t sum = 0; 1999 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2000 Metachunk* chunk = chunks_in_use(i); 2001 while (chunk != NULL) { 2002 sum += chunk->word_size(); 2003 chunk = chunk->next(); 2004 } 2005 } 2006 return sum; 2007 } 2008 } 2009 2010 size_t SpaceManager::sum_count_in_chunks_in_use() { 2011 size_t count = 0; 2012 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2013 count = count + sum_count_in_chunks_in_use(i); 2014 } 2015 2016 return count; 2017 } 2018 2019 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) { 2020 size_t count = 0; 2021 Metachunk* chunk = chunks_in_use(i); 2022 while (chunk != NULL) { 2023 count++; 2024 chunk = chunk->next(); 2025 } 2026 return count; 2027 } 2028 2029 2030 size_t SpaceManager::sum_used_in_chunks_in_use() const { 2031 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2032 size_t used = 0; 2033 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2034 Metachunk* chunk = chunks_in_use(i); 2035 while (chunk != NULL) { 2036 used += chunk->used_word_size(); 2037 chunk = chunk->next(); 2038 } 2039 } 2040 return used; 2041 } 2042 2043 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const { 2044 2045 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2046 Metachunk* chunk = chunks_in_use(i); 2047 st->print("SpaceManager: %s " PTR_FORMAT, 2048 chunk_size_name(i), p2i(chunk)); 2049 if (chunk != NULL) { 2050 st->print_cr(" free " SIZE_FORMAT, 2051 chunk->free_word_size()); 2052 } else { 2053 st->cr(); 2054 } 2055 } 2056 2057 chunk_manager()->locked_print_free_chunks(st); 2058 chunk_manager()->locked_print_sum_free_chunks(st); 2059 } 2060 2061 size_t SpaceManager::calc_chunk_size(size_t word_size) { 2062 2063 // Decide between a small chunk and a medium chunk. Up to 2064 // _small_chunk_limit small chunks can be allocated. 2065 // After that a medium chunk is preferred. 2066 size_t chunk_word_size; 2067 if (chunks_in_use(MediumIndex) == NULL && 2068 sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit) { 2069 chunk_word_size = (size_t) small_chunk_size(); 2070 if (word_size + Metachunk::overhead() > small_chunk_size()) { 2071 chunk_word_size = medium_chunk_size(); 2072 } 2073 } else { 2074 chunk_word_size = medium_chunk_size(); 2075 } 2076 2077 // Might still need a humongous chunk. Enforce 2078 // humongous allocations sizes to be aligned up to 2079 // the smallest chunk size. 2080 size_t if_humongous_sized_chunk = 2081 align_size_up(word_size + Metachunk::overhead(), 2082 smallest_chunk_size()); 2083 chunk_word_size = 2084 MAX2((size_t) chunk_word_size, if_humongous_sized_chunk); 2085 2086 assert(!SpaceManager::is_humongous(word_size) || 2087 chunk_word_size == if_humongous_sized_chunk, 2088 "Size calculation is wrong, word_size " SIZE_FORMAT 2089 " chunk_word_size " SIZE_FORMAT, 2090 word_size, chunk_word_size); 2091 Log(gc, metaspace, alloc) log; 2092 if (log.is_debug() && SpaceManager::is_humongous(word_size)) { 2093 log.debug("Metadata humongous allocation:"); 2094 log.debug(" word_size " PTR_FORMAT, word_size); 2095 log.debug(" chunk_word_size " PTR_FORMAT, chunk_word_size); 2096 log.debug(" chunk overhead " PTR_FORMAT, Metachunk::overhead()); 2097 } 2098 return chunk_word_size; 2099 } 2100 2101 void SpaceManager::track_metaspace_memory_usage() { 2102 if (is_init_completed()) { 2103 if (is_class()) { 2104 MemoryService::track_compressed_class_memory_usage(); 2105 } 2106 MemoryService::track_metaspace_memory_usage(); 2107 } 2108 } 2109 2110 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) { 2111 assert(vs_list()->current_virtual_space() != NULL, 2112 "Should have been set"); 2113 assert(current_chunk() == NULL || 2114 current_chunk()->allocate(word_size) == NULL, 2115 "Don't need to expand"); 2116 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 2117 2118 if (log_is_enabled(Trace, gc, metaspace, freelist)) { 2119 size_t words_left = 0; 2120 size_t words_used = 0; 2121 if (current_chunk() != NULL) { 2122 words_left = current_chunk()->free_word_size(); 2123 words_used = current_chunk()->used_word_size(); 2124 } 2125 log_trace(gc, metaspace, freelist)("SpaceManager::grow_and_allocate for " SIZE_FORMAT " words " SIZE_FORMAT " words used " SIZE_FORMAT " words left", 2126 word_size, words_used, words_left); 2127 } 2128 2129 // Get another chunk 2130 size_t grow_chunks_by_words = calc_chunk_size(word_size); 2131 Metachunk* next = get_new_chunk(word_size, grow_chunks_by_words); 2132 2133 MetaWord* mem = NULL; 2134 2135 // If a chunk was available, add it to the in-use chunk list 2136 // and do an allocation from it. 2137 if (next != NULL) { 2138 // Add to this manager's list of chunks in use. 2139 add_chunk(next, false); 2140 mem = next->allocate(word_size); 2141 } 2142 2143 // Track metaspace memory usage statistic. 2144 track_metaspace_memory_usage(); 2145 2146 return mem; 2147 } 2148 2149 void SpaceManager::print_on(outputStream* st) const { 2150 2151 for (ChunkIndex i = ZeroIndex; 2152 i < NumberOfInUseLists ; 2153 i = next_chunk_index(i) ) { 2154 st->print_cr(" chunks_in_use " PTR_FORMAT " chunk size " SIZE_FORMAT, 2155 p2i(chunks_in_use(i)), 2156 chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size()); 2157 } 2158 st->print_cr(" waste: Small " SIZE_FORMAT " Medium " SIZE_FORMAT 2159 " Humongous " SIZE_FORMAT, 2160 sum_waste_in_chunks_in_use(SmallIndex), 2161 sum_waste_in_chunks_in_use(MediumIndex), 2162 sum_waste_in_chunks_in_use(HumongousIndex)); 2163 // block free lists 2164 if (block_freelists() != NULL) { 2165 st->print_cr("total in block free lists " SIZE_FORMAT, 2166 block_freelists()->total_size()); 2167 } 2168 } 2169 2170 SpaceManager::SpaceManager(Metaspace::MetadataType mdtype, 2171 Mutex* lock) : 2172 _mdtype(mdtype), 2173 _allocated_blocks_words(0), 2174 _allocated_chunks_words(0), 2175 _allocated_chunks_count(0), 2176 _block_freelists(NULL), 2177 _lock(lock) 2178 { 2179 initialize(); 2180 } 2181 2182 void SpaceManager::inc_size_metrics(size_t words) { 2183 assert_lock_strong(SpaceManager::expand_lock()); 2184 // Total of allocated Metachunks and allocated Metachunks count 2185 // for each SpaceManager 2186 _allocated_chunks_words = _allocated_chunks_words + words; 2187 _allocated_chunks_count++; 2188 // Global total of capacity in allocated Metachunks 2189 MetaspaceAux::inc_capacity(mdtype(), words); 2190 // Global total of allocated Metablocks. 2191 // used_words_slow() includes the overhead in each 2192 // Metachunk so include it in the used when the 2193 // Metachunk is first added (so only added once per 2194 // Metachunk). 2195 MetaspaceAux::inc_used(mdtype(), Metachunk::overhead()); 2196 } 2197 2198 void SpaceManager::inc_used_metrics(size_t words) { 2199 // Add to the per SpaceManager total 2200 Atomic::add_ptr(words, &_allocated_blocks_words); 2201 // Add to the global total 2202 MetaspaceAux::inc_used(mdtype(), words); 2203 } 2204 2205 void SpaceManager::dec_total_from_size_metrics() { 2206 MetaspaceAux::dec_capacity(mdtype(), allocated_chunks_words()); 2207 MetaspaceAux::dec_used(mdtype(), allocated_blocks_words()); 2208 // Also deduct the overhead per Metachunk 2209 MetaspaceAux::dec_used(mdtype(), allocated_chunks_count() * Metachunk::overhead()); 2210 } 2211 2212 void SpaceManager::initialize() { 2213 Metadebug::init_allocation_fail_alot_count(); 2214 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2215 _chunks_in_use[i] = NULL; 2216 } 2217 _current_chunk = NULL; 2218 log_trace(gc, metaspace, freelist)("SpaceManager(): " PTR_FORMAT, p2i(this)); 2219 } 2220 2221 void ChunkManager::return_chunks(ChunkIndex index, Metachunk* chunks) { 2222 if (chunks == NULL) { 2223 return; 2224 } 2225 ChunkList* list = free_chunks(index); 2226 assert(list->size() == chunks->word_size(), "Mismatch in chunk sizes"); 2227 assert_lock_strong(SpaceManager::expand_lock()); 2228 Metachunk* cur = chunks; 2229 2230 // This returns chunks one at a time. If a new 2231 // class List can be created that is a base class 2232 // of FreeList then something like FreeList::prepend() 2233 // can be used in place of this loop 2234 while (cur != NULL) { 2235 assert(cur->container() != NULL, "Container should have been set"); 2236 cur->container()->dec_container_count(); 2237 // Capture the next link before it is changed 2238 // by the call to return_chunk_at_head(); 2239 Metachunk* next = cur->next(); 2240 DEBUG_ONLY(cur->set_is_tagged_free(true);) 2241 NOT_PRODUCT(cur->mangle(badMetaWordVal);) 2242 list->return_chunk_at_head(cur); 2243 cur = next; 2244 } 2245 } 2246 2247 SpaceManager::~SpaceManager() { 2248 // This call this->_lock which can't be done while holding expand_lock() 2249 assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(), 2250 "sum_capacity_in_chunks_in_use() " SIZE_FORMAT 2251 " allocated_chunks_words() " SIZE_FORMAT, 2252 sum_capacity_in_chunks_in_use(), allocated_chunks_words()); 2253 2254 MutexLockerEx fcl(SpaceManager::expand_lock(), 2255 Mutex::_no_safepoint_check_flag); 2256 2257 chunk_manager()->slow_locked_verify(); 2258 2259 dec_total_from_size_metrics(); 2260 2261 Log(gc, metaspace, freelist) log; 2262 if (log.is_trace()) { 2263 log.trace("~SpaceManager(): " PTR_FORMAT, p2i(this)); 2264 ResourceMark rm; 2265 locked_print_chunks_in_use_on(log.trace_stream()); 2266 if (block_freelists() != NULL) { 2267 block_freelists()->print_on(log.trace_stream()); 2268 } 2269 } 2270 2271 // Have to update before the chunks_in_use lists are emptied 2272 // below. 2273 chunk_manager()->inc_free_chunks_total(allocated_chunks_words(), 2274 sum_count_in_chunks_in_use()); 2275 2276 // Add all the chunks in use by this space manager 2277 // to the global list of free chunks. 2278 2279 // Follow each list of chunks-in-use and add them to the 2280 // free lists. Each list is NULL terminated. 2281 2282 for (ChunkIndex i = ZeroIndex; i < HumongousIndex; i = next_chunk_index(i)) { 2283 log.trace("returned " SIZE_FORMAT " %s chunks to freelist", sum_count_in_chunks_in_use(i), chunk_size_name(i)); 2284 Metachunk* chunks = chunks_in_use(i); 2285 chunk_manager()->return_chunks(i, chunks); 2286 set_chunks_in_use(i, NULL); 2287 log.trace("updated freelist count " SSIZE_FORMAT " %s", chunk_manager()->free_chunks(i)->count(), chunk_size_name(i)); 2288 assert(i != HumongousIndex, "Humongous chunks are handled explicitly later"); 2289 } 2290 2291 // The medium chunk case may be optimized by passing the head and 2292 // tail of the medium chunk list to add_at_head(). The tail is often 2293 // the current chunk but there are probably exceptions. 2294 2295 // Humongous chunks 2296 log.trace("returned " SIZE_FORMAT " %s humongous chunks to dictionary", 2297 sum_count_in_chunks_in_use(HumongousIndex), chunk_size_name(HumongousIndex)); 2298 log.trace("Humongous chunk dictionary: "); 2299 // Humongous chunks are never the current chunk. 2300 Metachunk* humongous_chunks = chunks_in_use(HumongousIndex); 2301 2302 while (humongous_chunks != NULL) { 2303 DEBUG_ONLY(humongous_chunks->set_is_tagged_free(true);) 2304 NOT_PRODUCT(humongous_chunks->mangle(badMetaWordVal);) 2305 log.trace(PTR_FORMAT " (" SIZE_FORMAT ") ", p2i(humongous_chunks), humongous_chunks->word_size()); 2306 assert(humongous_chunks->word_size() == (size_t) 2307 align_size_up(humongous_chunks->word_size(), 2308 smallest_chunk_size()), 2309 "Humongous chunk size is wrong: word size " SIZE_FORMAT 2310 " granularity " SIZE_FORMAT, 2311 humongous_chunks->word_size(), smallest_chunk_size()); 2312 Metachunk* next_humongous_chunks = humongous_chunks->next(); 2313 humongous_chunks->container()->dec_container_count(); 2314 chunk_manager()->humongous_dictionary()->return_chunk(humongous_chunks); 2315 humongous_chunks = next_humongous_chunks; 2316 } 2317 log.trace("updated dictionary count " SIZE_FORMAT " %s", chunk_manager()->humongous_dictionary()->total_count(), chunk_size_name(HumongousIndex)); 2318 chunk_manager()->slow_locked_verify(); 2319 2320 if (_block_freelists != NULL) { 2321 delete _block_freelists; 2322 } 2323 } 2324 2325 const char* SpaceManager::chunk_size_name(ChunkIndex index) const { 2326 switch (index) { 2327 case SpecializedIndex: 2328 return "Specialized"; 2329 case SmallIndex: 2330 return "Small"; 2331 case MediumIndex: 2332 return "Medium"; 2333 case HumongousIndex: 2334 return "Humongous"; 2335 default: 2336 return NULL; 2337 } 2338 } 2339 2340 ChunkIndex ChunkManager::list_index(size_t size) { 2341 switch (size) { 2342 case SpecializedChunk: 2343 assert(SpecializedChunk == ClassSpecializedChunk, 2344 "Need branch for ClassSpecializedChunk"); 2345 return SpecializedIndex; 2346 case SmallChunk: 2347 case ClassSmallChunk: 2348 return SmallIndex; 2349 case MediumChunk: 2350 case ClassMediumChunk: 2351 return MediumIndex; 2352 default: 2353 assert(size > MediumChunk || size > ClassMediumChunk, 2354 "Not a humongous chunk"); 2355 return HumongousIndex; 2356 } 2357 } 2358 2359 void SpaceManager::deallocate(MetaWord* p, size_t word_size) { 2360 assert_lock_strong(_lock); 2361 // Allocations and deallocations are in raw_word_size 2362 size_t raw_word_size = get_allocation_word_size(word_size); 2363 // Lazily create a block_freelist 2364 if (block_freelists() == NULL) { 2365 _block_freelists = new BlockFreelist(); 2366 } 2367 block_freelists()->return_block(p, raw_word_size); 2368 } 2369 2370 // Adds a chunk to the list of chunks in use. 2371 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) { 2372 2373 assert(new_chunk != NULL, "Should not be NULL"); 2374 assert(new_chunk->next() == NULL, "Should not be on a list"); 2375 2376 new_chunk->reset_empty(); 2377 2378 // Find the correct list and and set the current 2379 // chunk for that list. 2380 ChunkIndex index = ChunkManager::list_index(new_chunk->word_size()); 2381 2382 if (index != HumongousIndex) { 2383 retire_current_chunk(); 2384 set_current_chunk(new_chunk); 2385 new_chunk->set_next(chunks_in_use(index)); 2386 set_chunks_in_use(index, new_chunk); 2387 } else { 2388 // For null class loader data and DumpSharedSpaces, the first chunk isn't 2389 // small, so small will be null. Link this first chunk as the current 2390 // chunk. 2391 if (make_current) { 2392 // Set as the current chunk but otherwise treat as a humongous chunk. 2393 set_current_chunk(new_chunk); 2394 } 2395 // Link at head. The _current_chunk only points to a humongous chunk for 2396 // the null class loader metaspace (class and data virtual space managers) 2397 // any humongous chunks so will not point to the tail 2398 // of the humongous chunks list. 2399 new_chunk->set_next(chunks_in_use(HumongousIndex)); 2400 set_chunks_in_use(HumongousIndex, new_chunk); 2401 2402 assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency"); 2403 } 2404 2405 // Add to the running sum of capacity 2406 inc_size_metrics(new_chunk->word_size()); 2407 2408 assert(new_chunk->is_empty(), "Not ready for reuse"); 2409 Log(gc, metaspace, freelist) log; 2410 if (log.is_trace()) { 2411 log.trace("SpaceManager::add_chunk: " SIZE_FORMAT ") ", sum_count_in_chunks_in_use()); 2412 ResourceMark rm; 2413 outputStream* out = log.trace_stream(); 2414 new_chunk->print_on(out); 2415 chunk_manager()->locked_print_free_chunks(out); 2416 } 2417 } 2418 2419 void SpaceManager::retire_current_chunk() { 2420 if (current_chunk() != NULL) { 2421 size_t remaining_words = current_chunk()->free_word_size(); 2422 if (remaining_words >= BlockFreelist::min_dictionary_size()) { 2423 MetaWord* ptr = current_chunk()->allocate(remaining_words); 2424 deallocate(ptr, remaining_words); 2425 inc_used_metrics(remaining_words); 2426 } 2427 } 2428 } 2429 2430 Metachunk* SpaceManager::get_new_chunk(size_t word_size, 2431 size_t grow_chunks_by_words) { 2432 // Get a chunk from the chunk freelist 2433 Metachunk* next = chunk_manager()->chunk_freelist_allocate(grow_chunks_by_words); 2434 2435 if (next == NULL) { 2436 next = vs_list()->get_new_chunk(word_size, 2437 grow_chunks_by_words, 2438 medium_chunk_bunch()); 2439 } 2440 2441 Log(gc, metaspace, alloc) log; 2442 if (log.is_debug() && next != NULL && 2443 SpaceManager::is_humongous(next->word_size())) { 2444 log.debug(" new humongous chunk word size " PTR_FORMAT, next->word_size()); 2445 } 2446 2447 return next; 2448 } 2449 2450 /* 2451 * The policy is to allocate up to _small_chunk_limit small chunks 2452 * after which only medium chunks are allocated. This is done to 2453 * reduce fragmentation. In some cases, this can result in a lot 2454 * of small chunks being allocated to the point where it's not 2455 * possible to expand. If this happens, there may be no medium chunks 2456 * available and OOME would be thrown. Instead of doing that, 2457 * if the allocation request size fits in a small chunk, an attempt 2458 * will be made to allocate a small chunk. 2459 */ 2460 MetaWord* SpaceManager::get_small_chunk_and_allocate(size_t word_size) { 2461 size_t raw_word_size = get_allocation_word_size(word_size); 2462 2463 if (raw_word_size + Metachunk::overhead() > small_chunk_size()) { 2464 return NULL; 2465 } 2466 2467 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2468 MutexLockerEx cl1(expand_lock(), Mutex::_no_safepoint_check_flag); 2469 2470 Metachunk* chunk = chunk_manager()->chunk_freelist_allocate(small_chunk_size()); 2471 2472 MetaWord* mem = NULL; 2473 2474 if (chunk != NULL) { 2475 // Add chunk to the in-use chunk list and do an allocation from it. 2476 // Add to this manager's list of chunks in use. 2477 add_chunk(chunk, false); 2478 mem = chunk->allocate(raw_word_size); 2479 2480 inc_used_metrics(raw_word_size); 2481 2482 // Track metaspace memory usage statistic. 2483 track_metaspace_memory_usage(); 2484 } 2485 2486 return mem; 2487 } 2488 2489 MetaWord* SpaceManager::allocate(size_t word_size) { 2490 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2491 size_t raw_word_size = get_allocation_word_size(word_size); 2492 BlockFreelist* fl = block_freelists(); 2493 MetaWord* p = NULL; 2494 // Allocation from the dictionary is expensive in the sense that 2495 // the dictionary has to be searched for a size. Don't allocate 2496 // from the dictionary until it starts to get fat. Is this 2497 // a reasonable policy? Maybe an skinny dictionary is fast enough 2498 // for allocations. Do some profiling. JJJ 2499 if (fl != NULL && fl->total_size() > allocation_from_dictionary_limit) { 2500 p = fl->get_block(raw_word_size); 2501 } 2502 if (p == NULL) { 2503 p = allocate_work(raw_word_size); 2504 } 2505 2506 return p; 2507 } 2508 2509 // Returns the address of spaced allocated for "word_size". 2510 // This methods does not know about blocks (Metablocks) 2511 MetaWord* SpaceManager::allocate_work(size_t word_size) { 2512 assert_lock_strong(_lock); 2513 #ifdef ASSERT 2514 if (Metadebug::test_metadata_failure()) { 2515 return NULL; 2516 } 2517 #endif 2518 // Is there space in the current chunk? 2519 MetaWord* result = NULL; 2520 2521 // For DumpSharedSpaces, only allocate out of the current chunk which is 2522 // never null because we gave it the size we wanted. Caller reports out 2523 // of memory if this returns null. 2524 if (DumpSharedSpaces) { 2525 assert(current_chunk() != NULL, "should never happen"); 2526 inc_used_metrics(word_size); 2527 return current_chunk()->allocate(word_size); // caller handles null result 2528 } 2529 2530 if (current_chunk() != NULL) { 2531 result = current_chunk()->allocate(word_size); 2532 } 2533 2534 if (result == NULL) { 2535 result = grow_and_allocate(word_size); 2536 } 2537 2538 if (result != NULL) { 2539 inc_used_metrics(word_size); 2540 assert(result != (MetaWord*) chunks_in_use(MediumIndex), 2541 "Head of the list is being allocated"); 2542 } 2543 2544 return result; 2545 } 2546 2547 void SpaceManager::verify() { 2548 // If there are blocks in the dictionary, then 2549 // verification of chunks does not work since 2550 // being in the dictionary alters a chunk. 2551 if (block_freelists() != NULL && block_freelists()->total_size() == 0) { 2552 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2553 Metachunk* curr = chunks_in_use(i); 2554 while (curr != NULL) { 2555 curr->verify(); 2556 verify_chunk_size(curr); 2557 curr = curr->next(); 2558 } 2559 } 2560 } 2561 } 2562 2563 void SpaceManager::verify_chunk_size(Metachunk* chunk) { 2564 assert(is_humongous(chunk->word_size()) || 2565 chunk->word_size() == medium_chunk_size() || 2566 chunk->word_size() == small_chunk_size() || 2567 chunk->word_size() == specialized_chunk_size(), 2568 "Chunk size is wrong"); 2569 return; 2570 } 2571 2572 #ifdef ASSERT 2573 void SpaceManager::verify_allocated_blocks_words() { 2574 // Verification is only guaranteed at a safepoint. 2575 assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(), 2576 "Verification can fail if the applications is running"); 2577 assert(allocated_blocks_words() == sum_used_in_chunks_in_use(), 2578 "allocation total is not consistent " SIZE_FORMAT 2579 " vs " SIZE_FORMAT, 2580 allocated_blocks_words(), sum_used_in_chunks_in_use()); 2581 } 2582 2583 #endif 2584 2585 void SpaceManager::dump(outputStream* const out) const { 2586 size_t curr_total = 0; 2587 size_t waste = 0; 2588 uint i = 0; 2589 size_t used = 0; 2590 size_t capacity = 0; 2591 2592 // Add up statistics for all chunks in this SpaceManager. 2593 for (ChunkIndex index = ZeroIndex; 2594 index < NumberOfInUseLists; 2595 index = next_chunk_index(index)) { 2596 for (Metachunk* curr = chunks_in_use(index); 2597 curr != NULL; 2598 curr = curr->next()) { 2599 out->print("%d) ", i++); 2600 curr->print_on(out); 2601 curr_total += curr->word_size(); 2602 used += curr->used_word_size(); 2603 capacity += curr->word_size(); 2604 waste += curr->free_word_size() + curr->overhead();; 2605 } 2606 } 2607 2608 if (log_is_enabled(Trace, gc, metaspace, freelist)) { 2609 if (block_freelists() != NULL) block_freelists()->print_on(out); 2610 } 2611 2612 size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size(); 2613 // Free space isn't wasted. 2614 waste -= free; 2615 2616 out->print_cr("total of all chunks " SIZE_FORMAT " used " SIZE_FORMAT 2617 " free " SIZE_FORMAT " capacity " SIZE_FORMAT 2618 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste); 2619 } 2620 2621 // MetaspaceAux 2622 2623 2624 size_t MetaspaceAux::_capacity_words[] = {0, 0}; 2625 size_t MetaspaceAux::_used_words[] = {0, 0}; 2626 2627 size_t MetaspaceAux::free_bytes(Metaspace::MetadataType mdtype) { 2628 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2629 return list == NULL ? 0 : list->free_bytes(); 2630 } 2631 2632 size_t MetaspaceAux::free_bytes() { 2633 return free_bytes(Metaspace::ClassType) + free_bytes(Metaspace::NonClassType); 2634 } 2635 2636 void MetaspaceAux::dec_capacity(Metaspace::MetadataType mdtype, size_t words) { 2637 assert_lock_strong(SpaceManager::expand_lock()); 2638 assert(words <= capacity_words(mdtype), 2639 "About to decrement below 0: words " SIZE_FORMAT 2640 " is greater than _capacity_words[%u] " SIZE_FORMAT, 2641 words, mdtype, capacity_words(mdtype)); 2642 _capacity_words[mdtype] -= words; 2643 } 2644 2645 void MetaspaceAux::inc_capacity(Metaspace::MetadataType mdtype, size_t words) { 2646 assert_lock_strong(SpaceManager::expand_lock()); 2647 // Needs to be atomic 2648 _capacity_words[mdtype] += words; 2649 } 2650 2651 void MetaspaceAux::dec_used(Metaspace::MetadataType mdtype, size_t words) { 2652 assert(words <= used_words(mdtype), 2653 "About to decrement below 0: words " SIZE_FORMAT 2654 " is greater than _used_words[%u] " SIZE_FORMAT, 2655 words, mdtype, used_words(mdtype)); 2656 // For CMS deallocation of the Metaspaces occurs during the 2657 // sweep which is a concurrent phase. Protection by the expand_lock() 2658 // is not enough since allocation is on a per Metaspace basis 2659 // and protected by the Metaspace lock. 2660 jlong minus_words = (jlong) - (jlong) words; 2661 Atomic::add_ptr(minus_words, &_used_words[mdtype]); 2662 } 2663 2664 void MetaspaceAux::inc_used(Metaspace::MetadataType mdtype, size_t words) { 2665 // _used_words tracks allocations for 2666 // each piece of metadata. Those allocations are 2667 // generally done concurrently by different application 2668 // threads so must be done atomically. 2669 Atomic::add_ptr(words, &_used_words[mdtype]); 2670 } 2671 2672 size_t MetaspaceAux::used_bytes_slow(Metaspace::MetadataType mdtype) { 2673 size_t used = 0; 2674 ClassLoaderDataGraphMetaspaceIterator iter; 2675 while (iter.repeat()) { 2676 Metaspace* msp = iter.get_next(); 2677 // Sum allocated_blocks_words for each metaspace 2678 if (msp != NULL) { 2679 used += msp->used_words_slow(mdtype); 2680 } 2681 } 2682 return used * BytesPerWord; 2683 } 2684 2685 size_t MetaspaceAux::free_bytes_slow(Metaspace::MetadataType mdtype) { 2686 size_t free = 0; 2687 ClassLoaderDataGraphMetaspaceIterator iter; 2688 while (iter.repeat()) { 2689 Metaspace* msp = iter.get_next(); 2690 if (msp != NULL) { 2691 free += msp->free_words_slow(mdtype); 2692 } 2693 } 2694 return free * BytesPerWord; 2695 } 2696 2697 size_t MetaspaceAux::capacity_bytes_slow(Metaspace::MetadataType mdtype) { 2698 if ((mdtype == Metaspace::ClassType) && !Metaspace::using_class_space()) { 2699 return 0; 2700 } 2701 // Don't count the space in the freelists. That space will be 2702 // added to the capacity calculation as needed. 2703 size_t capacity = 0; 2704 ClassLoaderDataGraphMetaspaceIterator iter; 2705 while (iter.repeat()) { 2706 Metaspace* msp = iter.get_next(); 2707 if (msp != NULL) { 2708 capacity += msp->capacity_words_slow(mdtype); 2709 } 2710 } 2711 return capacity * BytesPerWord; 2712 } 2713 2714 size_t MetaspaceAux::capacity_bytes_slow() { 2715 #ifdef PRODUCT 2716 // Use capacity_bytes() in PRODUCT instead of this function. 2717 guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT"); 2718 #endif 2719 size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType); 2720 size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType); 2721 assert(capacity_bytes() == class_capacity + non_class_capacity, 2722 "bad accounting: capacity_bytes() " SIZE_FORMAT 2723 " class_capacity + non_class_capacity " SIZE_FORMAT 2724 " class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT, 2725 capacity_bytes(), class_capacity + non_class_capacity, 2726 class_capacity, non_class_capacity); 2727 2728 return class_capacity + non_class_capacity; 2729 } 2730 2731 size_t MetaspaceAux::reserved_bytes(Metaspace::MetadataType mdtype) { 2732 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2733 return list == NULL ? 0 : list->reserved_bytes(); 2734 } 2735 2736 size_t MetaspaceAux::committed_bytes(Metaspace::MetadataType mdtype) { 2737 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2738 return list == NULL ? 0 : list->committed_bytes(); 2739 } 2740 2741 size_t MetaspaceAux::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); } 2742 2743 size_t MetaspaceAux::free_chunks_total_words(Metaspace::MetadataType mdtype) { 2744 ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype); 2745 if (chunk_manager == NULL) { 2746 return 0; 2747 } 2748 chunk_manager->slow_verify(); 2749 return chunk_manager->free_chunks_total_words(); 2750 } 2751 2752 size_t MetaspaceAux::free_chunks_total_bytes(Metaspace::MetadataType mdtype) { 2753 return free_chunks_total_words(mdtype) * BytesPerWord; 2754 } 2755 2756 size_t MetaspaceAux::free_chunks_total_words() { 2757 return free_chunks_total_words(Metaspace::ClassType) + 2758 free_chunks_total_words(Metaspace::NonClassType); 2759 } 2760 2761 size_t MetaspaceAux::free_chunks_total_bytes() { 2762 return free_chunks_total_words() * BytesPerWord; 2763 } 2764 2765 bool MetaspaceAux::has_chunk_free_list(Metaspace::MetadataType mdtype) { 2766 return Metaspace::get_chunk_manager(mdtype) != NULL; 2767 } 2768 2769 MetaspaceChunkFreeListSummary MetaspaceAux::chunk_free_list_summary(Metaspace::MetadataType mdtype) { 2770 if (!has_chunk_free_list(mdtype)) { 2771 return MetaspaceChunkFreeListSummary(); 2772 } 2773 2774 const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype); 2775 return cm->chunk_free_list_summary(); 2776 } 2777 2778 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) { 2779 log_info(gc, metaspace)("Metaspace: " SIZE_FORMAT "K->" SIZE_FORMAT "K(" SIZE_FORMAT "K)", 2780 prev_metadata_used/K, used_bytes()/K, reserved_bytes()/K); 2781 } 2782 2783 void MetaspaceAux::print_on(outputStream* out) { 2784 Metaspace::MetadataType nct = Metaspace::NonClassType; 2785 2786 out->print_cr(" Metaspace " 2787 "used " SIZE_FORMAT "K, " 2788 "capacity " SIZE_FORMAT "K, " 2789 "committed " SIZE_FORMAT "K, " 2790 "reserved " SIZE_FORMAT "K", 2791 used_bytes()/K, 2792 capacity_bytes()/K, 2793 committed_bytes()/K, 2794 reserved_bytes()/K); 2795 2796 if (Metaspace::using_class_space()) { 2797 Metaspace::MetadataType ct = Metaspace::ClassType; 2798 out->print_cr(" class space " 2799 "used " SIZE_FORMAT "K, " 2800 "capacity " SIZE_FORMAT "K, " 2801 "committed " SIZE_FORMAT "K, " 2802 "reserved " SIZE_FORMAT "K", 2803 used_bytes(ct)/K, 2804 capacity_bytes(ct)/K, 2805 committed_bytes(ct)/K, 2806 reserved_bytes(ct)/K); 2807 } 2808 } 2809 2810 // Print information for class space and data space separately. 2811 // This is almost the same as above. 2812 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) { 2813 size_t free_chunks_capacity_bytes = free_chunks_total_bytes(mdtype); 2814 size_t capacity_bytes = capacity_bytes_slow(mdtype); 2815 size_t used_bytes = used_bytes_slow(mdtype); 2816 size_t free_bytes = free_bytes_slow(mdtype); 2817 size_t used_and_free = used_bytes + free_bytes + 2818 free_chunks_capacity_bytes; 2819 out->print_cr(" Chunk accounting: used in chunks " SIZE_FORMAT 2820 "K + unused in chunks " SIZE_FORMAT "K + " 2821 " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT 2822 "K capacity in allocated chunks " SIZE_FORMAT "K", 2823 used_bytes / K, 2824 free_bytes / K, 2825 free_chunks_capacity_bytes / K, 2826 used_and_free / K, 2827 capacity_bytes / K); 2828 // Accounting can only be correct if we got the values during a safepoint 2829 assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong"); 2830 } 2831 2832 // Print total fragmentation for class metaspaces 2833 void MetaspaceAux::print_class_waste(outputStream* out) { 2834 assert(Metaspace::using_class_space(), "class metaspace not used"); 2835 size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0; 2836 size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_humongous_count = 0; 2837 ClassLoaderDataGraphMetaspaceIterator iter; 2838 while (iter.repeat()) { 2839 Metaspace* msp = iter.get_next(); 2840 if (msp != NULL) { 2841 cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex); 2842 cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex); 2843 cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex); 2844 cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex); 2845 cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex); 2846 cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex); 2847 cls_humongous_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex); 2848 } 2849 } 2850 out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", " 2851 SIZE_FORMAT " small(s) " SIZE_FORMAT ", " 2852 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", " 2853 "large count " SIZE_FORMAT, 2854 cls_specialized_count, cls_specialized_waste, 2855 cls_small_count, cls_small_waste, 2856 cls_medium_count, cls_medium_waste, cls_humongous_count); 2857 } 2858 2859 // Print total fragmentation for data and class metaspaces separately 2860 void MetaspaceAux::print_waste(outputStream* out) { 2861 size_t specialized_waste = 0, small_waste = 0, medium_waste = 0; 2862 size_t specialized_count = 0, small_count = 0, medium_count = 0, humongous_count = 0; 2863 2864 ClassLoaderDataGraphMetaspaceIterator iter; 2865 while (iter.repeat()) { 2866 Metaspace* msp = iter.get_next(); 2867 if (msp != NULL) { 2868 specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex); 2869 specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex); 2870 small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex); 2871 small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex); 2872 medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex); 2873 medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex); 2874 humongous_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex); 2875 } 2876 } 2877 out->print_cr("Total fragmentation waste (words) doesn't count free space"); 2878 out->print_cr(" data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", " 2879 SIZE_FORMAT " small(s) " SIZE_FORMAT ", " 2880 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", " 2881 "large count " SIZE_FORMAT, 2882 specialized_count, specialized_waste, small_count, 2883 small_waste, medium_count, medium_waste, humongous_count); 2884 if (Metaspace::using_class_space()) { 2885 print_class_waste(out); 2886 } 2887 } 2888 2889 // Dump global metaspace things from the end of ClassLoaderDataGraph 2890 void MetaspaceAux::dump(outputStream* out) { 2891 out->print_cr("All Metaspace:"); 2892 out->print("data space: "); print_on(out, Metaspace::NonClassType); 2893 out->print("class space: "); print_on(out, Metaspace::ClassType); 2894 print_waste(out); 2895 } 2896 2897 void MetaspaceAux::verify_free_chunks() { 2898 Metaspace::chunk_manager_metadata()->verify(); 2899 if (Metaspace::using_class_space()) { 2900 Metaspace::chunk_manager_class()->verify(); 2901 } 2902 } 2903 2904 void MetaspaceAux::verify_capacity() { 2905 #ifdef ASSERT 2906 size_t running_sum_capacity_bytes = capacity_bytes(); 2907 // For purposes of the running sum of capacity, verify against capacity 2908 size_t capacity_in_use_bytes = capacity_bytes_slow(); 2909 assert(running_sum_capacity_bytes == capacity_in_use_bytes, 2910 "capacity_words() * BytesPerWord " SIZE_FORMAT 2911 " capacity_bytes_slow()" SIZE_FORMAT, 2912 running_sum_capacity_bytes, capacity_in_use_bytes); 2913 for (Metaspace::MetadataType i = Metaspace::ClassType; 2914 i < Metaspace:: MetadataTypeCount; 2915 i = (Metaspace::MetadataType)(i + 1)) { 2916 size_t capacity_in_use_bytes = capacity_bytes_slow(i); 2917 assert(capacity_bytes(i) == capacity_in_use_bytes, 2918 "capacity_bytes(%u) " SIZE_FORMAT 2919 " capacity_bytes_slow(%u)" SIZE_FORMAT, 2920 i, capacity_bytes(i), i, capacity_in_use_bytes); 2921 } 2922 #endif 2923 } 2924 2925 void MetaspaceAux::verify_used() { 2926 #ifdef ASSERT 2927 size_t running_sum_used_bytes = used_bytes(); 2928 // For purposes of the running sum of used, verify against used 2929 size_t used_in_use_bytes = used_bytes_slow(); 2930 assert(used_bytes() == used_in_use_bytes, 2931 "used_bytes() " SIZE_FORMAT 2932 " used_bytes_slow()" SIZE_FORMAT, 2933 used_bytes(), used_in_use_bytes); 2934 for (Metaspace::MetadataType i = Metaspace::ClassType; 2935 i < Metaspace:: MetadataTypeCount; 2936 i = (Metaspace::MetadataType)(i + 1)) { 2937 size_t used_in_use_bytes = used_bytes_slow(i); 2938 assert(used_bytes(i) == used_in_use_bytes, 2939 "used_bytes(%u) " SIZE_FORMAT 2940 " used_bytes_slow(%u)" SIZE_FORMAT, 2941 i, used_bytes(i), i, used_in_use_bytes); 2942 } 2943 #endif 2944 } 2945 2946 void MetaspaceAux::verify_metrics() { 2947 verify_capacity(); 2948 verify_used(); 2949 } 2950 2951 2952 // Metaspace methods 2953 2954 size_t Metaspace::_first_chunk_word_size = 0; 2955 size_t Metaspace::_first_class_chunk_word_size = 0; 2956 2957 size_t Metaspace::_commit_alignment = 0; 2958 size_t Metaspace::_reserve_alignment = 0; 2959 2960 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) { 2961 initialize(lock, type); 2962 } 2963 2964 Metaspace::~Metaspace() { 2965 delete _vsm; 2966 if (using_class_space()) { 2967 delete _class_vsm; 2968 } 2969 } 2970 2971 VirtualSpaceList* Metaspace::_space_list = NULL; 2972 VirtualSpaceList* Metaspace::_class_space_list = NULL; 2973 2974 ChunkManager* Metaspace::_chunk_manager_metadata = NULL; 2975 ChunkManager* Metaspace::_chunk_manager_class = NULL; 2976 2977 #define VIRTUALSPACEMULTIPLIER 2 2978 2979 #ifdef _LP64 2980 static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1); 2981 2982 void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) { 2983 // Figure out the narrow_klass_base and the narrow_klass_shift. The 2984 // narrow_klass_base is the lower of the metaspace base and the cds base 2985 // (if cds is enabled). The narrow_klass_shift depends on the distance 2986 // between the lower base and higher address. 2987 address lower_base; 2988 address higher_address; 2989 #if INCLUDE_CDS 2990 if (UseSharedSpaces) { 2991 higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()), 2992 (address)(metaspace_base + compressed_class_space_size())); 2993 lower_base = MIN2(metaspace_base, cds_base); 2994 } else 2995 #endif 2996 { 2997 higher_address = metaspace_base + compressed_class_space_size(); 2998 lower_base = metaspace_base; 2999 3000 uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes; 3001 // If compressed class space fits in lower 32G, we don't need a base. 3002 if (higher_address <= (address)klass_encoding_max) { 3003 lower_base = 0; // Effectively lower base is zero. 3004 } 3005 } 3006 3007 Universe::set_narrow_klass_base(lower_base); 3008 3009 if ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) { 3010 Universe::set_narrow_klass_shift(0); 3011 } else { 3012 assert(!UseSharedSpaces, "Cannot shift with UseSharedSpaces"); 3013 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes); 3014 } 3015 } 3016 3017 #if INCLUDE_CDS 3018 // Return TRUE if the specified metaspace_base and cds_base are close enough 3019 // to work with compressed klass pointers. 3020 bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) { 3021 assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS"); 3022 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); 3023 address lower_base = MIN2((address)metaspace_base, cds_base); 3024 address higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()), 3025 (address)(metaspace_base + compressed_class_space_size())); 3026 return ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax); 3027 } 3028 #endif 3029 3030 // Try to allocate the metaspace at the requested addr. 3031 void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) { 3032 assert(using_class_space(), "called improperly"); 3033 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); 3034 assert(compressed_class_space_size() < KlassEncodingMetaspaceMax, 3035 "Metaspace size is too big"); 3036 assert_is_ptr_aligned(requested_addr, _reserve_alignment); 3037 assert_is_ptr_aligned(cds_base, _reserve_alignment); 3038 assert_is_size_aligned(compressed_class_space_size(), _reserve_alignment); 3039 3040 // Don't use large pages for the class space. 3041 bool large_pages = false; 3042 3043 #if !(defined(AARCH64) || defined(AIX)) 3044 ReservedSpace metaspace_rs = ReservedSpace(compressed_class_space_size(), 3045 _reserve_alignment, 3046 large_pages, 3047 requested_addr); 3048 #else // AARCH64 3049 ReservedSpace metaspace_rs; 3050 3051 // Our compressed klass pointers may fit nicely into the lower 32 3052 // bits. 3053 if ((uint64_t)requested_addr + compressed_class_space_size() < 4*G) { 3054 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3055 _reserve_alignment, 3056 large_pages, 3057 requested_addr); 3058 } 3059 3060 if (! metaspace_rs.is_reserved()) { 3061 // Aarch64: Try to align metaspace so that we can decode a compressed 3062 // klass with a single MOVK instruction. We can do this iff the 3063 // compressed class base is a multiple of 4G. 3064 // Aix: Search for a place where we can find memory. If we need to load 3065 // the base, 4G alignment is helpful, too. 3066 size_t increment = AARCH64_ONLY(4*)G; 3067 for (char *a = (char*)align_ptr_up(requested_addr, increment); 3068 a < (char*)(1024*G); 3069 a += increment) { 3070 if (a == (char *)(32*G)) { 3071 // Go faster from here on. Zero-based is no longer possible. 3072 increment = 4*G; 3073 } 3074 3075 #if INCLUDE_CDS 3076 if (UseSharedSpaces 3077 && ! can_use_cds_with_metaspace_addr(a, cds_base)) { 3078 // We failed to find an aligned base that will reach. Fall 3079 // back to using our requested addr. 3080 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3081 _reserve_alignment, 3082 large_pages, 3083 requested_addr); 3084 break; 3085 } 3086 #endif 3087 3088 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3089 _reserve_alignment, 3090 large_pages, 3091 a); 3092 if (metaspace_rs.is_reserved()) 3093 break; 3094 } 3095 } 3096 3097 #endif // AARCH64 3098 3099 if (!metaspace_rs.is_reserved()) { 3100 #if INCLUDE_CDS 3101 if (UseSharedSpaces) { 3102 size_t increment = align_size_up(1*G, _reserve_alignment); 3103 3104 // Keep trying to allocate the metaspace, increasing the requested_addr 3105 // by 1GB each time, until we reach an address that will no longer allow 3106 // use of CDS with compressed klass pointers. 3107 char *addr = requested_addr; 3108 while (!metaspace_rs.is_reserved() && (addr + increment > addr) && 3109 can_use_cds_with_metaspace_addr(addr + increment, cds_base)) { 3110 addr = addr + increment; 3111 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3112 _reserve_alignment, large_pages, addr); 3113 } 3114 } 3115 #endif 3116 // If no successful allocation then try to allocate the space anywhere. If 3117 // that fails then OOM doom. At this point we cannot try allocating the 3118 // metaspace as if UseCompressedClassPointers is off because too much 3119 // initialization has happened that depends on UseCompressedClassPointers. 3120 // So, UseCompressedClassPointers cannot be turned off at this point. 3121 if (!metaspace_rs.is_reserved()) { 3122 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3123 _reserve_alignment, large_pages); 3124 if (!metaspace_rs.is_reserved()) { 3125 vm_exit_during_initialization(err_msg("Could not allocate metaspace: " SIZE_FORMAT " bytes", 3126 compressed_class_space_size())); 3127 } 3128 } 3129 } 3130 3131 // If we got here then the metaspace got allocated. 3132 MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass); 3133 3134 #if INCLUDE_CDS 3135 // Verify that we can use shared spaces. Otherwise, turn off CDS. 3136 if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) { 3137 FileMapInfo::stop_sharing_and_unmap( 3138 "Could not allocate metaspace at a compatible address"); 3139 } 3140 #endif 3141 set_narrow_klass_base_and_shift((address)metaspace_rs.base(), 3142 UseSharedSpaces ? (address)cds_base : 0); 3143 3144 initialize_class_space(metaspace_rs); 3145 3146 if (log_is_enabled(Trace, gc, metaspace)) { 3147 Log(gc, metaspace) log; 3148 ResourceMark rm; 3149 print_compressed_class_space(log.trace_stream(), requested_addr); 3150 } 3151 } 3152 3153 void Metaspace::print_compressed_class_space(outputStream* st, const char* requested_addr) { 3154 st->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: %d", 3155 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift()); 3156 if (_class_space_list != NULL) { 3157 address base = (address)_class_space_list->current_virtual_space()->bottom(); 3158 st->print("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT, 3159 compressed_class_space_size(), p2i(base)); 3160 if (requested_addr != 0) { 3161 st->print(" Req Addr: " PTR_FORMAT, p2i(requested_addr)); 3162 } 3163 st->cr(); 3164 } 3165 } 3166 3167 // For UseCompressedClassPointers the class space is reserved above the top of 3168 // the Java heap. The argument passed in is at the base of the compressed space. 3169 void Metaspace::initialize_class_space(ReservedSpace rs) { 3170 // The reserved space size may be bigger because of alignment, esp with UseLargePages 3171 assert(rs.size() >= CompressedClassSpaceSize, 3172 SIZE_FORMAT " != " SIZE_FORMAT, rs.size(), CompressedClassSpaceSize); 3173 assert(using_class_space(), "Must be using class space"); 3174 _class_space_list = new VirtualSpaceList(rs); 3175 _chunk_manager_class = new ChunkManager(SpecializedChunk, ClassSmallChunk, ClassMediumChunk); 3176 3177 if (!_class_space_list->initialization_succeeded()) { 3178 vm_exit_during_initialization("Failed to setup compressed class space virtual space list."); 3179 } 3180 } 3181 3182 #endif 3183 3184 void Metaspace::ergo_initialize() { 3185 if (DumpSharedSpaces) { 3186 // Using large pages when dumping the shared archive is currently not implemented. 3187 FLAG_SET_ERGO(bool, UseLargePagesInMetaspace, false); 3188 } 3189 3190 size_t page_size = os::vm_page_size(); 3191 if (UseLargePages && UseLargePagesInMetaspace) { 3192 page_size = os::large_page_size(); 3193 } 3194 3195 _commit_alignment = page_size; 3196 _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity()); 3197 3198 // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will 3199 // override if MaxMetaspaceSize was set on the command line or not. 3200 // This information is needed later to conform to the specification of the 3201 // java.lang.management.MemoryUsage API. 3202 // 3203 // Ideally, we would be able to set the default value of MaxMetaspaceSize in 3204 // globals.hpp to the aligned value, but this is not possible, since the 3205 // alignment depends on other flags being parsed. 3206 MaxMetaspaceSize = align_size_down_bounded(MaxMetaspaceSize, _reserve_alignment); 3207 3208 if (MetaspaceSize > MaxMetaspaceSize) { 3209 MetaspaceSize = MaxMetaspaceSize; 3210 } 3211 3212 MetaspaceSize = align_size_down_bounded(MetaspaceSize, _commit_alignment); 3213 3214 assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize"); 3215 3216 MinMetaspaceExpansion = align_size_down_bounded(MinMetaspaceExpansion, _commit_alignment); 3217 MaxMetaspaceExpansion = align_size_down_bounded(MaxMetaspaceExpansion, _commit_alignment); 3218 3219 CompressedClassSpaceSize = align_size_down_bounded(CompressedClassSpaceSize, _reserve_alignment); 3220 set_compressed_class_space_size(CompressedClassSpaceSize); 3221 } 3222 3223 void Metaspace::global_initialize() { 3224 MetaspaceGC::initialize(); 3225 3226 // Initialize the alignment for shared spaces. 3227 int max_alignment = os::vm_allocation_granularity(); 3228 size_t cds_total = 0; 3229 3230 MetaspaceShared::set_max_alignment(max_alignment); 3231 3232 if (DumpSharedSpaces) { 3233 #if INCLUDE_CDS 3234 MetaspaceShared::estimate_regions_size(); 3235 3236 SharedReadOnlySize = align_size_up(SharedReadOnlySize, max_alignment); 3237 SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment); 3238 SharedMiscDataSize = align_size_up(SharedMiscDataSize, max_alignment); 3239 SharedMiscCodeSize = align_size_up(SharedMiscCodeSize, max_alignment); 3240 3241 // Initialize with the sum of the shared space sizes. The read-only 3242 // and read write metaspace chunks will be allocated out of this and the 3243 // remainder is the misc code and data chunks. 3244 cds_total = FileMapInfo::shared_spaces_size(); 3245 cds_total = align_size_up(cds_total, _reserve_alignment); 3246 _space_list = new VirtualSpaceList(cds_total/wordSize); 3247 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk); 3248 3249 if (!_space_list->initialization_succeeded()) { 3250 vm_exit_during_initialization("Unable to dump shared archive.", NULL); 3251 } 3252 3253 #ifdef _LP64 3254 if (cds_total + compressed_class_space_size() > UnscaledClassSpaceMax) { 3255 vm_exit_during_initialization("Unable to dump shared archive.", 3256 err_msg("Size of archive (" SIZE_FORMAT ") + compressed class space (" 3257 SIZE_FORMAT ") == total (" SIZE_FORMAT ") is larger than compressed " 3258 "klass limit: " UINT64_FORMAT, cds_total, compressed_class_space_size(), 3259 cds_total + compressed_class_space_size(), UnscaledClassSpaceMax)); 3260 } 3261 3262 // Set the compressed klass pointer base so that decoding of these pointers works 3263 // properly when creating the shared archive. 3264 assert(UseCompressedOops && UseCompressedClassPointers, 3265 "UseCompressedOops and UseCompressedClassPointers must be set"); 3266 Universe::set_narrow_klass_base((address)_space_list->current_virtual_space()->bottom()); 3267 log_develop_trace(gc, metaspace)("Setting_narrow_klass_base to Address: " PTR_FORMAT, 3268 p2i(_space_list->current_virtual_space()->bottom())); 3269 3270 Universe::set_narrow_klass_shift(0); 3271 #endif // _LP64 3272 #endif // INCLUDE_CDS 3273 } else { 3274 #if INCLUDE_CDS 3275 if (UseSharedSpaces) { 3276 // If using shared space, open the file that contains the shared space 3277 // and map in the memory before initializing the rest of metaspace (so 3278 // the addresses don't conflict) 3279 address cds_address = NULL; 3280 FileMapInfo* mapinfo = new FileMapInfo(); 3281 3282 // Open the shared archive file, read and validate the header. If 3283 // initialization fails, shared spaces [UseSharedSpaces] are 3284 // disabled and the file is closed. 3285 // Map in spaces now also 3286 if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) { 3287 cds_total = FileMapInfo::shared_spaces_size(); 3288 cds_address = (address)mapinfo->header()->region_addr(0); 3289 #ifdef _LP64 3290 if (using_class_space()) { 3291 char* cds_end = (char*)(cds_address + cds_total); 3292 cds_end = (char *)align_ptr_up(cds_end, _reserve_alignment); 3293 // If UseCompressedClassPointers is set then allocate the metaspace area 3294 // above the heap and above the CDS area (if it exists). 3295 allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address); 3296 // Map the shared string space after compressed pointers 3297 // because it relies on compressed class pointers setting to work 3298 mapinfo->map_string_regions(); 3299 } 3300 #endif // _LP64 3301 } else { 3302 assert(!mapinfo->is_open() && !UseSharedSpaces, 3303 "archive file not closed or shared spaces not disabled."); 3304 } 3305 } 3306 #endif // INCLUDE_CDS 3307 3308 #ifdef _LP64 3309 if (!UseSharedSpaces && using_class_space()) { 3310 char* base = (char*)align_ptr_up(Universe::heap()->reserved_region().end(), _reserve_alignment); 3311 allocate_metaspace_compressed_klass_ptrs(base, 0); 3312 } 3313 #endif // _LP64 3314 3315 // Initialize these before initializing the VirtualSpaceList 3316 _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord; 3317 _first_chunk_word_size = align_word_size_up(_first_chunk_word_size); 3318 // Make the first class chunk bigger than a medium chunk so it's not put 3319 // on the medium chunk list. The next chunk will be small and progress 3320 // from there. This size calculated by -version. 3321 _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6, 3322 (CompressedClassSpaceSize/BytesPerWord)*2); 3323 _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size); 3324 // Arbitrarily set the initial virtual space to a multiple 3325 // of the boot class loader size. 3326 size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size; 3327 word_size = align_size_up(word_size, Metaspace::reserve_alignment_words()); 3328 3329 // Initialize the list of virtual spaces. 3330 _space_list = new VirtualSpaceList(word_size); 3331 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk); 3332 3333 if (!_space_list->initialization_succeeded()) { 3334 vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL); 3335 } 3336 } 3337 3338 _tracer = new MetaspaceTracer(); 3339 } 3340 3341 void Metaspace::post_initialize() { 3342 MetaspaceGC::post_initialize(); 3343 } 3344 3345 Metachunk* Metaspace::get_initialization_chunk(MetadataType mdtype, 3346 size_t chunk_word_size, 3347 size_t chunk_bunch) { 3348 // Get a chunk from the chunk freelist 3349 Metachunk* chunk = get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size); 3350 if (chunk != NULL) { 3351 return chunk; 3352 } 3353 3354 return get_space_list(mdtype)->get_new_chunk(chunk_word_size, chunk_word_size, chunk_bunch); 3355 } 3356 3357 void Metaspace::initialize(Mutex* lock, MetaspaceType type) { 3358 3359 assert(space_list() != NULL, 3360 "Metadata VirtualSpaceList has not been initialized"); 3361 assert(chunk_manager_metadata() != NULL, 3362 "Metadata ChunkManager has not been initialized"); 3363 3364 _vsm = new SpaceManager(NonClassType, lock); 3365 if (_vsm == NULL) { 3366 return; 3367 } 3368 size_t word_size; 3369 size_t class_word_size; 3370 vsm()->get_initial_chunk_sizes(type, &word_size, &class_word_size); 3371 3372 if (using_class_space()) { 3373 assert(class_space_list() != NULL, 3374 "Class VirtualSpaceList has not been initialized"); 3375 assert(chunk_manager_class() != NULL, 3376 "Class ChunkManager has not been initialized"); 3377 3378 // Allocate SpaceManager for classes. 3379 _class_vsm = new SpaceManager(ClassType, lock); 3380 if (_class_vsm == NULL) { 3381 return; 3382 } 3383 } 3384 3385 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3386 3387 // Allocate chunk for metadata objects 3388 Metachunk* new_chunk = get_initialization_chunk(NonClassType, 3389 word_size, 3390 vsm()->medium_chunk_bunch()); 3391 // For dumping shared archive, report error if allocation has failed. 3392 if (DumpSharedSpaces && new_chunk == NULL) { 3393 report_insufficient_metaspace(MetaspaceAux::committed_bytes() + word_size * BytesPerWord); 3394 } 3395 assert(!DumpSharedSpaces || new_chunk != NULL, "should have enough space for both chunks"); 3396 if (new_chunk != NULL) { 3397 // Add to this manager's list of chunks in use and current_chunk(). 3398 vsm()->add_chunk(new_chunk, true); 3399 } 3400 3401 // Allocate chunk for class metadata objects 3402 if (using_class_space()) { 3403 Metachunk* class_chunk = get_initialization_chunk(ClassType, 3404 class_word_size, 3405 class_vsm()->medium_chunk_bunch()); 3406 if (class_chunk != NULL) { 3407 class_vsm()->add_chunk(class_chunk, true); 3408 } else { 3409 // For dumping shared archive, report error if allocation has failed. 3410 if (DumpSharedSpaces) { 3411 report_insufficient_metaspace(MetaspaceAux::committed_bytes() + class_word_size * BytesPerWord); 3412 } 3413 } 3414 } 3415 3416 _alloc_record_head = NULL; 3417 _alloc_record_tail = NULL; 3418 } 3419 3420 size_t Metaspace::align_word_size_up(size_t word_size) { 3421 size_t byte_size = word_size * wordSize; 3422 return ReservedSpace::allocation_align_size_up(byte_size) / wordSize; 3423 } 3424 3425 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) { 3426 // DumpSharedSpaces doesn't use class metadata area (yet) 3427 // Also, don't use class_vsm() unless UseCompressedClassPointers is true. 3428 if (is_class_space_allocation(mdtype)) { 3429 return class_vsm()->allocate(word_size); 3430 } else { 3431 return vsm()->allocate(word_size); 3432 } 3433 } 3434 3435 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) { 3436 size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord); 3437 assert(delta_bytes > 0, "Must be"); 3438 3439 size_t before = 0; 3440 size_t after = 0; 3441 MetaWord* res; 3442 bool incremented; 3443 3444 // Each thread increments the HWM at most once. Even if the thread fails to increment 3445 // the HWM, an allocation is still attempted. This is because another thread must then 3446 // have incremented the HWM and therefore the allocation might still succeed. 3447 do { 3448 incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before); 3449 res = allocate(word_size, mdtype); 3450 } while (!incremented && res == NULL); 3451 3452 if (incremented) { 3453 tracer()->report_gc_threshold(before, after, 3454 MetaspaceGCThresholdUpdater::ExpandAndAllocate); 3455 log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after); 3456 } 3457 3458 return res; 3459 } 3460 3461 // Space allocated in the Metaspace. This may 3462 // be across several metadata virtual spaces. 3463 char* Metaspace::bottom() const { 3464 assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces"); 3465 return (char*)vsm()->current_chunk()->bottom(); 3466 } 3467 3468 size_t Metaspace::used_words_slow(MetadataType mdtype) const { 3469 if (mdtype == ClassType) { 3470 return using_class_space() ? class_vsm()->sum_used_in_chunks_in_use() : 0; 3471 } else { 3472 return vsm()->sum_used_in_chunks_in_use(); // includes overhead! 3473 } 3474 } 3475 3476 size_t Metaspace::free_words_slow(MetadataType mdtype) const { 3477 if (mdtype == ClassType) { 3478 return using_class_space() ? class_vsm()->sum_free_in_chunks_in_use() : 0; 3479 } else { 3480 return vsm()->sum_free_in_chunks_in_use(); 3481 } 3482 } 3483 3484 // Space capacity in the Metaspace. It includes 3485 // space in the list of chunks from which allocations 3486 // have been made. Don't include space in the global freelist and 3487 // in the space available in the dictionary which 3488 // is already counted in some chunk. 3489 size_t Metaspace::capacity_words_slow(MetadataType mdtype) const { 3490 if (mdtype == ClassType) { 3491 return using_class_space() ? class_vsm()->sum_capacity_in_chunks_in_use() : 0; 3492 } else { 3493 return vsm()->sum_capacity_in_chunks_in_use(); 3494 } 3495 } 3496 3497 size_t Metaspace::used_bytes_slow(MetadataType mdtype) const { 3498 return used_words_slow(mdtype) * BytesPerWord; 3499 } 3500 3501 size_t Metaspace::capacity_bytes_slow(MetadataType mdtype) const { 3502 return capacity_words_slow(mdtype) * BytesPerWord; 3503 } 3504 3505 size_t Metaspace::allocated_blocks_bytes() const { 3506 return vsm()->allocated_blocks_bytes() + 3507 (using_class_space() ? class_vsm()->allocated_blocks_bytes() : 0); 3508 } 3509 3510 size_t Metaspace::allocated_chunks_bytes() const { 3511 return vsm()->allocated_chunks_bytes() + 3512 (using_class_space() ? class_vsm()->allocated_chunks_bytes() : 0); 3513 } 3514 3515 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) { 3516 assert(!SafepointSynchronize::is_at_safepoint() 3517 || Thread::current()->is_VM_thread(), "should be the VM thread"); 3518 3519 if (DumpSharedSpaces && PrintSharedSpaces) { 3520 record_deallocation(ptr, vsm()->get_allocation_word_size(word_size)); 3521 } 3522 3523 MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag); 3524 3525 if (is_class && using_class_space()) { 3526 class_vsm()->deallocate(ptr, word_size); 3527 } else { 3528 vsm()->deallocate(ptr, word_size); 3529 } 3530 } 3531 3532 3533 MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size, 3534 bool read_only, MetaspaceObj::Type type, TRAPS) { 3535 if (HAS_PENDING_EXCEPTION) { 3536 assert(false, "Should not allocate with exception pending"); 3537 return NULL; // caller does a CHECK_NULL too 3538 } 3539 3540 assert(loader_data != NULL, "Should never pass around a NULL loader_data. " 3541 "ClassLoaderData::the_null_class_loader_data() should have been used."); 3542 3543 // Allocate in metaspaces without taking out a lock, because it deadlocks 3544 // with the SymbolTable_lock. Dumping is single threaded for now. We'll have 3545 // to revisit this for application class data sharing. 3546 if (DumpSharedSpaces) { 3547 assert(type > MetaspaceObj::UnknownType && type < MetaspaceObj::_number_of_types, "sanity"); 3548 Metaspace* space = read_only ? loader_data->ro_metaspace() : loader_data->rw_metaspace(); 3549 MetaWord* result = space->allocate(word_size, NonClassType); 3550 if (result == NULL) { 3551 report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite); 3552 } 3553 if (PrintSharedSpaces) { 3554 space->record_allocation(result, type, space->vsm()->get_allocation_word_size(word_size)); 3555 } 3556 3557 // Zero initialize. 3558 Copy::fill_to_words((HeapWord*)result, word_size, 0); 3559 3560 return result; 3561 } 3562 3563 MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType; 3564 3565 // Try to allocate metadata. 3566 MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype); 3567 3568 if (result == NULL) { 3569 tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype); 3570 3571 // Allocation failed. 3572 if (is_init_completed()) { 3573 // Only start a GC if the bootstrapping has completed. 3574 3575 // Try to clean out some memory and retry. 3576 result = Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation( 3577 loader_data, word_size, mdtype); 3578 } 3579 } 3580 3581 if (result == NULL) { 3582 SpaceManager* sm; 3583 if (is_class_space_allocation(mdtype)) { 3584 sm = loader_data->metaspace_non_null()->class_vsm(); 3585 } else { 3586 sm = loader_data->metaspace_non_null()->vsm(); 3587 } 3588 3589 result = sm->get_small_chunk_and_allocate(word_size); 3590 3591 if (result == NULL) { 3592 report_metadata_oome(loader_data, word_size, type, mdtype, CHECK_NULL); 3593 } 3594 } 3595 3596 // Zero initialize. 3597 Copy::fill_to_words((HeapWord*)result, word_size, 0); 3598 3599 return result; 3600 } 3601 3602 size_t Metaspace::class_chunk_size(size_t word_size) { 3603 assert(using_class_space(), "Has to use class space"); 3604 return class_vsm()->calc_chunk_size(word_size); 3605 } 3606 3607 void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) { 3608 tracer()->report_metadata_oom(loader_data, word_size, type, mdtype); 3609 3610 // If result is still null, we are out of memory. 3611 Log(gc, metaspace, freelist) log; 3612 if (log.is_info()) { 3613 log.info("Metaspace (%s) allocation failed for size " SIZE_FORMAT, 3614 is_class_space_allocation(mdtype) ? "class" : "data", word_size); 3615 ResourceMark rm; 3616 outputStream* out = log.info_stream(); 3617 if (loader_data->metaspace_or_null() != NULL) { 3618 loader_data->dump(out); 3619 } 3620 MetaspaceAux::dump(out); 3621 } 3622 3623 bool out_of_compressed_class_space = false; 3624 if (is_class_space_allocation(mdtype)) { 3625 Metaspace* metaspace = loader_data->metaspace_non_null(); 3626 out_of_compressed_class_space = 3627 MetaspaceAux::committed_bytes(Metaspace::ClassType) + 3628 (metaspace->class_chunk_size(word_size) * BytesPerWord) > 3629 CompressedClassSpaceSize; 3630 } 3631 3632 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support 3633 const char* space_string = out_of_compressed_class_space ? 3634 "Compressed class space" : "Metaspace"; 3635 3636 report_java_out_of_memory(space_string); 3637 3638 if (JvmtiExport::should_post_resource_exhausted()) { 3639 JvmtiExport::post_resource_exhausted( 3640 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR, 3641 space_string); 3642 } 3643 3644 if (!is_init_completed()) { 3645 vm_exit_during_initialization("OutOfMemoryError", space_string); 3646 } 3647 3648 if (out_of_compressed_class_space) { 3649 THROW_OOP(Universe::out_of_memory_error_class_metaspace()); 3650 } else { 3651 THROW_OOP(Universe::out_of_memory_error_metaspace()); 3652 } 3653 } 3654 3655 const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) { 3656 switch (mdtype) { 3657 case Metaspace::ClassType: return "Class"; 3658 case Metaspace::NonClassType: return "Metadata"; 3659 default: 3660 assert(false, "Got bad mdtype: %d", (int) mdtype); 3661 return NULL; 3662 } 3663 } 3664 3665 void Metaspace::record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size) { 3666 assert(DumpSharedSpaces, "sanity"); 3667 3668 int byte_size = (int)word_size * wordSize; 3669 AllocRecord *rec = new AllocRecord((address)ptr, type, byte_size); 3670 3671 if (_alloc_record_head == NULL) { 3672 _alloc_record_head = _alloc_record_tail = rec; 3673 } else if (_alloc_record_tail->_ptr + _alloc_record_tail->_byte_size == (address)ptr) { 3674 _alloc_record_tail->_next = rec; 3675 _alloc_record_tail = rec; 3676 } else { 3677 // slow linear search, but this doesn't happen that often, and only when dumping 3678 for (AllocRecord *old = _alloc_record_head; old; old = old->_next) { 3679 if (old->_ptr == ptr) { 3680 assert(old->_type == MetaspaceObj::DeallocatedType, "sanity"); 3681 int remain_bytes = old->_byte_size - byte_size; 3682 assert(remain_bytes >= 0, "sanity"); 3683 old->_type = type; 3684 3685 if (remain_bytes == 0) { 3686 delete(rec); 3687 } else { 3688 address remain_ptr = address(ptr) + byte_size; 3689 rec->_ptr = remain_ptr; 3690 rec->_byte_size = remain_bytes; 3691 rec->_type = MetaspaceObj::DeallocatedType; 3692 rec->_next = old->_next; 3693 old->_byte_size = byte_size; 3694 old->_next = rec; 3695 } 3696 return; 3697 } 3698 } 3699 assert(0, "reallocating a freed pointer that was not recorded"); 3700 } 3701 } 3702 3703 void Metaspace::record_deallocation(void* ptr, size_t word_size) { 3704 assert(DumpSharedSpaces, "sanity"); 3705 3706 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) { 3707 if (rec->_ptr == ptr) { 3708 assert(rec->_byte_size == (int)word_size * wordSize, "sanity"); 3709 rec->_type = MetaspaceObj::DeallocatedType; 3710 return; 3711 } 3712 } 3713 3714 assert(0, "deallocating a pointer that was not recorded"); 3715 } 3716 3717 void Metaspace::iterate(Metaspace::AllocRecordClosure *closure) { 3718 assert(DumpSharedSpaces, "unimplemented for !DumpSharedSpaces"); 3719 3720 address last_addr = (address)bottom(); 3721 3722 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) { 3723 address ptr = rec->_ptr; 3724 if (last_addr < ptr) { 3725 closure->doit(last_addr, MetaspaceObj::UnknownType, ptr - last_addr); 3726 } 3727 closure->doit(ptr, rec->_type, rec->_byte_size); 3728 last_addr = ptr + rec->_byte_size; 3729 } 3730 3731 address top = ((address)bottom()) + used_bytes_slow(Metaspace::NonClassType); 3732 if (last_addr < top) { 3733 closure->doit(last_addr, MetaspaceObj::UnknownType, top - last_addr); 3734 } 3735 } 3736 3737 void Metaspace::purge(MetadataType mdtype) { 3738 get_space_list(mdtype)->purge(get_chunk_manager(mdtype)); 3739 } 3740 3741 void Metaspace::purge() { 3742 MutexLockerEx cl(SpaceManager::expand_lock(), 3743 Mutex::_no_safepoint_check_flag); 3744 purge(NonClassType); 3745 if (using_class_space()) { 3746 purge(ClassType); 3747 } 3748 } 3749 3750 void Metaspace::print_on(outputStream* out) const { 3751 // Print both class virtual space counts and metaspace. 3752 if (Verbose) { 3753 vsm()->print_on(out); 3754 if (using_class_space()) { 3755 class_vsm()->print_on(out); 3756 } 3757 } 3758 } 3759 3760 bool Metaspace::contains(const void* ptr) { 3761 if (UseSharedSpaces && MetaspaceShared::is_in_shared_space(ptr)) { 3762 return true; 3763 } 3764 3765 if (using_class_space() && get_space_list(ClassType)->contains(ptr)) { 3766 return true; 3767 } 3768 3769 return get_space_list(NonClassType)->contains(ptr); 3770 } 3771 3772 void Metaspace::verify() { 3773 vsm()->verify(); 3774 if (using_class_space()) { 3775 class_vsm()->verify(); 3776 } 3777 } 3778 3779 void Metaspace::dump(outputStream* const out) const { 3780 out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, p2i(vsm())); 3781 vsm()->dump(out); 3782 if (using_class_space()) { 3783 out->print_cr("\nClass space manager: " INTPTR_FORMAT, p2i(class_vsm())); 3784 class_vsm()->dump(out); 3785 } 3786 } 3787 3788 /////////////// Unit tests /////////////// 3789 3790 #ifndef PRODUCT 3791 3792 class TestMetaspaceAuxTest : AllStatic { 3793 public: 3794 static void test_reserved() { 3795 size_t reserved = MetaspaceAux::reserved_bytes(); 3796 3797 assert(reserved > 0, "assert"); 3798 3799 size_t committed = MetaspaceAux::committed_bytes(); 3800 assert(committed <= reserved, "assert"); 3801 3802 size_t reserved_metadata = MetaspaceAux::reserved_bytes(Metaspace::NonClassType); 3803 assert(reserved_metadata > 0, "assert"); 3804 assert(reserved_metadata <= reserved, "assert"); 3805 3806 if (UseCompressedClassPointers) { 3807 size_t reserved_class = MetaspaceAux::reserved_bytes(Metaspace::ClassType); 3808 assert(reserved_class > 0, "assert"); 3809 assert(reserved_class < reserved, "assert"); 3810 } 3811 } 3812 3813 static void test_committed() { 3814 size_t committed = MetaspaceAux::committed_bytes(); 3815 3816 assert(committed > 0, "assert"); 3817 3818 size_t reserved = MetaspaceAux::reserved_bytes(); 3819 assert(committed <= reserved, "assert"); 3820 3821 size_t committed_metadata = MetaspaceAux::committed_bytes(Metaspace::NonClassType); 3822 assert(committed_metadata > 0, "assert"); 3823 assert(committed_metadata <= committed, "assert"); 3824 3825 if (UseCompressedClassPointers) { 3826 size_t committed_class = MetaspaceAux::committed_bytes(Metaspace::ClassType); 3827 assert(committed_class > 0, "assert"); 3828 assert(committed_class < committed, "assert"); 3829 } 3830 } 3831 3832 static void test_virtual_space_list_large_chunk() { 3833 VirtualSpaceList* vs_list = new VirtualSpaceList(os::vm_allocation_granularity()); 3834 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3835 // A size larger than VirtualSpaceSize (256k) and add one page to make it _not_ be 3836 // vm_allocation_granularity aligned on Windows. 3837 size_t large_size = (size_t)(2*256*K + (os::vm_page_size()/BytesPerWord)); 3838 large_size += (os::vm_page_size()/BytesPerWord); 3839 vs_list->get_new_chunk(large_size, large_size, 0); 3840 } 3841 3842 static void test() { 3843 test_reserved(); 3844 test_committed(); 3845 test_virtual_space_list_large_chunk(); 3846 } 3847 }; 3848 3849 void TestMetaspaceAux_test() { 3850 TestMetaspaceAuxTest::test(); 3851 } 3852 3853 class TestVirtualSpaceNodeTest { 3854 static void chunk_up(size_t words_left, size_t& num_medium_chunks, 3855 size_t& num_small_chunks, 3856 size_t& num_specialized_chunks) { 3857 num_medium_chunks = words_left / MediumChunk; 3858 words_left = words_left % MediumChunk; 3859 3860 num_small_chunks = words_left / SmallChunk; 3861 words_left = words_left % SmallChunk; 3862 // how many specialized chunks can we get? 3863 num_specialized_chunks = words_left / SpecializedChunk; 3864 assert(words_left % SpecializedChunk == 0, "should be nothing left"); 3865 } 3866 3867 public: 3868 static void test() { 3869 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3870 const size_t vsn_test_size_words = MediumChunk * 4; 3871 const size_t vsn_test_size_bytes = vsn_test_size_words * BytesPerWord; 3872 3873 // The chunk sizes must be multiples of eachother, or this will fail 3874 STATIC_ASSERT(MediumChunk % SmallChunk == 0); 3875 STATIC_ASSERT(SmallChunk % SpecializedChunk == 0); 3876 3877 { // No committed memory in VSN 3878 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3879 VirtualSpaceNode vsn(vsn_test_size_bytes); 3880 vsn.initialize(); 3881 vsn.retire(&cm); 3882 assert(cm.sum_free_chunks_count() == 0, "did not commit any memory in the VSN"); 3883 } 3884 3885 { // All of VSN is committed, half is used by chunks 3886 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3887 VirtualSpaceNode vsn(vsn_test_size_bytes); 3888 vsn.initialize(); 3889 vsn.expand_by(vsn_test_size_words, vsn_test_size_words); 3890 vsn.get_chunk_vs(MediumChunk); 3891 vsn.get_chunk_vs(MediumChunk); 3892 vsn.retire(&cm); 3893 assert(cm.sum_free_chunks_count() == 2, "should have been memory left for 2 medium chunks"); 3894 assert(cm.sum_free_chunks() == 2*MediumChunk, "sizes should add up"); 3895 } 3896 3897 const size_t page_chunks = 4 * (size_t)os::vm_page_size() / BytesPerWord; 3898 // This doesn't work for systems with vm_page_size >= 16K. 3899 if (page_chunks < MediumChunk) { 3900 // 4 pages of VSN is committed, some is used by chunks 3901 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3902 VirtualSpaceNode vsn(vsn_test_size_bytes); 3903 3904 vsn.initialize(); 3905 vsn.expand_by(page_chunks, page_chunks); 3906 vsn.get_chunk_vs(SmallChunk); 3907 vsn.get_chunk_vs(SpecializedChunk); 3908 vsn.retire(&cm); 3909 3910 // committed - used = words left to retire 3911 const size_t words_left = page_chunks - SmallChunk - SpecializedChunk; 3912 3913 size_t num_medium_chunks, num_small_chunks, num_spec_chunks; 3914 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks); 3915 3916 assert(num_medium_chunks == 0, "should not get any medium chunks"); 3917 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks"); 3918 assert(cm.sum_free_chunks() == words_left, "sizes should add up"); 3919 } 3920 3921 { // Half of VSN is committed, a humongous chunk is used 3922 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3923 VirtualSpaceNode vsn(vsn_test_size_bytes); 3924 vsn.initialize(); 3925 vsn.expand_by(MediumChunk * 2, MediumChunk * 2); 3926 vsn.get_chunk_vs(MediumChunk + SpecializedChunk); // Humongous chunks will be aligned up to MediumChunk + SpecializedChunk 3927 vsn.retire(&cm); 3928 3929 const size_t words_left = MediumChunk * 2 - (MediumChunk + SpecializedChunk); 3930 size_t num_medium_chunks, num_small_chunks, num_spec_chunks; 3931 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks); 3932 3933 assert(num_medium_chunks == 0, "should not get any medium chunks"); 3934 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks"); 3935 assert(cm.sum_free_chunks() == words_left, "sizes should add up"); 3936 } 3937 3938 } 3939 3940 #define assert_is_available_positive(word_size) \ 3941 assert(vsn.is_available(word_size), \ 3942 #word_size ": " PTR_FORMAT " bytes were not available in " \ 3943 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \ 3944 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())); 3945 3946 #define assert_is_available_negative(word_size) \ 3947 assert(!vsn.is_available(word_size), \ 3948 #word_size ": " PTR_FORMAT " bytes should not be available in " \ 3949 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \ 3950 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())); 3951 3952 static void test_is_available_positive() { 3953 // Reserve some memory. 3954 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 3955 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 3956 3957 // Commit some memory. 3958 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 3959 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 3960 assert(expanded, "Failed to commit"); 3961 3962 // Check that is_available accepts the committed size. 3963 assert_is_available_positive(commit_word_size); 3964 3965 // Check that is_available accepts half the committed size. 3966 size_t expand_word_size = commit_word_size / 2; 3967 assert_is_available_positive(expand_word_size); 3968 } 3969 3970 static void test_is_available_negative() { 3971 // Reserve some memory. 3972 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 3973 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 3974 3975 // Commit some memory. 3976 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 3977 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 3978 assert(expanded, "Failed to commit"); 3979 3980 // Check that is_available doesn't accept a too large size. 3981 size_t two_times_commit_word_size = commit_word_size * 2; 3982 assert_is_available_negative(two_times_commit_word_size); 3983 } 3984 3985 static void test_is_available_overflow() { 3986 // Reserve some memory. 3987 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 3988 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 3989 3990 // Commit some memory. 3991 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 3992 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 3993 assert(expanded, "Failed to commit"); 3994 3995 // Calculate a size that will overflow the virtual space size. 3996 void* virtual_space_max = (void*)(uintptr_t)-1; 3997 size_t bottom_to_max = pointer_delta(virtual_space_max, vsn.bottom(), 1); 3998 size_t overflow_size = bottom_to_max + BytesPerWord; 3999 size_t overflow_word_size = overflow_size / BytesPerWord; 4000 4001 // Check that is_available can handle the overflow. 4002 assert_is_available_negative(overflow_word_size); 4003 } 4004 4005 static void test_is_available() { 4006 TestVirtualSpaceNodeTest::test_is_available_positive(); 4007 TestVirtualSpaceNodeTest::test_is_available_negative(); 4008 TestVirtualSpaceNodeTest::test_is_available_overflow(); 4009 } 4010 }; 4011 4012 void TestVirtualSpaceNode_test() { 4013 TestVirtualSpaceNodeTest::test(); 4014 TestVirtualSpaceNodeTest::test_is_available(); 4015 } 4016 #endif