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.inline.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 // Used to manage the free list of Metablocks (a block corresponds 253 // to the allocation of a quantum of metadata). 254 class BlockFreelist VALUE_OBJ_CLASS_SPEC { 255 BlockTreeDictionary* const _dictionary; 256 257 // Only allocate and split from freelist if the size of the allocation 258 // is at least 1/4th the size of the available block. 259 const static int WasteMultiplier = 4; 260 261 // Accessors 262 BlockTreeDictionary* dictionary() const { return _dictionary; } 263 264 public: 265 BlockFreelist(); 266 ~BlockFreelist(); 267 268 // Get and return a block to the free list 269 MetaWord* get_block(size_t word_size); 270 void return_block(MetaWord* p, size_t word_size); 271 272 size_t total_size() { return dictionary()->total_size(); } 273 274 void print_on(outputStream* st) const; 275 }; 276 277 // A VirtualSpaceList node. 278 class VirtualSpaceNode : public CHeapObj<mtClass> { 279 friend class VirtualSpaceList; 280 281 // Link to next VirtualSpaceNode 282 VirtualSpaceNode* _next; 283 284 // total in the VirtualSpace 285 MemRegion _reserved; 286 ReservedSpace _rs; 287 VirtualSpace _virtual_space; 288 MetaWord* _top; 289 // count of chunks contained in this VirtualSpace 290 uintx _container_count; 291 292 // Convenience functions to access the _virtual_space 293 char* low() const { return virtual_space()->low(); } 294 char* high() const { return virtual_space()->high(); } 295 296 // The first Metachunk will be allocated at the bottom of the 297 // VirtualSpace 298 Metachunk* first_chunk() { return (Metachunk*) bottom(); } 299 300 // Committed but unused space in the virtual space 301 size_t free_words_in_vs() const; 302 public: 303 304 VirtualSpaceNode(size_t byte_size); 305 VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs), _container_count(0) {} 306 ~VirtualSpaceNode(); 307 308 // Convenience functions for logical bottom and end 309 MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); } 310 MetaWord* end() const { return (MetaWord*) _virtual_space.high(); } 311 312 bool contains(const void* ptr) { return ptr >= low() && ptr < high(); } 313 314 size_t reserved_words() const { return _virtual_space.reserved_size() / BytesPerWord; } 315 size_t committed_words() const { return _virtual_space.actual_committed_size() / BytesPerWord; } 316 317 bool is_pre_committed() const { return _virtual_space.special(); } 318 319 // address of next available space in _virtual_space; 320 // Accessors 321 VirtualSpaceNode* next() { return _next; } 322 void set_next(VirtualSpaceNode* v) { _next = v; } 323 324 void set_reserved(MemRegion const v) { _reserved = v; } 325 void set_top(MetaWord* v) { _top = v; } 326 327 // Accessors 328 MemRegion* reserved() { return &_reserved; } 329 VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; } 330 331 // Returns true if "word_size" is available in the VirtualSpace 332 bool is_available(size_t word_size) { return word_size <= pointer_delta(end(), _top, sizeof(MetaWord)); } 333 334 MetaWord* top() const { return _top; } 335 void inc_top(size_t word_size) { _top += word_size; } 336 337 uintx container_count() { return _container_count; } 338 void inc_container_count(); 339 void dec_container_count(); 340 #ifdef ASSERT 341 uintx container_count_slow(); 342 void verify_container_count(); 343 #endif 344 345 // used and capacity in this single entry in the list 346 size_t used_words_in_vs() const; 347 size_t capacity_words_in_vs() const; 348 349 bool initialize(); 350 351 // get space from the virtual space 352 Metachunk* take_from_committed(size_t chunk_word_size); 353 354 // Allocate a chunk from the virtual space and return it. 355 Metachunk* get_chunk_vs(size_t chunk_word_size); 356 357 // Expands/shrinks the committed space in a virtual space. Delegates 358 // to Virtualspace 359 bool expand_by(size_t min_words, size_t preferred_words); 360 361 // In preparation for deleting this node, remove all the chunks 362 // in the node from any freelist. 363 void purge(ChunkManager* chunk_manager); 364 365 // If an allocation doesn't fit in the current node a new node is created. 366 // Allocate chunks out of the remaining committed space in this node 367 // to avoid wasting that memory. 368 // This always adds up because all the chunk sizes are multiples of 369 // the smallest chunk size. 370 void retire(ChunkManager* chunk_manager); 371 372 #ifdef ASSERT 373 // Debug support 374 void mangle(); 375 #endif 376 377 void print_on(outputStream* st) const; 378 }; 379 380 #define assert_is_ptr_aligned(ptr, alignment) \ 381 assert(is_ptr_aligned(ptr, alignment), \ 382 PTR_FORMAT " is not aligned to " \ 383 SIZE_FORMAT, p2i(ptr), alignment) 384 385 #define assert_is_size_aligned(size, alignment) \ 386 assert(is_size_aligned(size, alignment), \ 387 SIZE_FORMAT " is not aligned to " \ 388 SIZE_FORMAT, size, alignment) 389 390 391 // Decide if large pages should be committed when the memory is reserved. 392 static bool should_commit_large_pages_when_reserving(size_t bytes) { 393 if (UseLargePages && UseLargePagesInMetaspace && !os::can_commit_large_page_memory()) { 394 size_t words = bytes / BytesPerWord; 395 bool is_class = false; // We never reserve large pages for the class space. 396 if (MetaspaceGC::can_expand(words, is_class) && 397 MetaspaceGC::allowed_expansion() >= words) { 398 return true; 399 } 400 } 401 402 return false; 403 } 404 405 // byte_size is the size of the associated virtualspace. 406 VirtualSpaceNode::VirtualSpaceNode(size_t bytes) : _top(NULL), _next(NULL), _rs(), _container_count(0) { 407 assert_is_size_aligned(bytes, Metaspace::reserve_alignment()); 408 409 #if INCLUDE_CDS 410 // This allocates memory with mmap. For DumpSharedspaces, try to reserve 411 // configurable address, generally at the top of the Java heap so other 412 // memory addresses don't conflict. 413 if (DumpSharedSpaces) { 414 bool large_pages = false; // No large pages when dumping the CDS archive. 415 char* shared_base = (char*)align_ptr_up((char*)SharedBaseAddress, Metaspace::reserve_alignment()); 416 417 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages, shared_base); 418 if (_rs.is_reserved()) { 419 assert(shared_base == 0 || _rs.base() == shared_base, "should match"); 420 } else { 421 // Get a mmap region anywhere if the SharedBaseAddress fails. 422 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages); 423 } 424 MetaspaceShared::initialize_shared_rs(&_rs); 425 } else 426 #endif 427 { 428 bool large_pages = should_commit_large_pages_when_reserving(bytes); 429 430 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages); 431 } 432 433 if (_rs.is_reserved()) { 434 assert(_rs.base() != NULL, "Catch if we get a NULL address"); 435 assert(_rs.size() != 0, "Catch if we get a 0 size"); 436 assert_is_ptr_aligned(_rs.base(), Metaspace::reserve_alignment()); 437 assert_is_size_aligned(_rs.size(), Metaspace::reserve_alignment()); 438 439 MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass); 440 } 441 } 442 443 void VirtualSpaceNode::purge(ChunkManager* chunk_manager) { 444 Metachunk* chunk = first_chunk(); 445 Metachunk* invalid_chunk = (Metachunk*) top(); 446 while (chunk < invalid_chunk ) { 447 assert(chunk->is_tagged_free(), "Should be tagged free"); 448 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 449 chunk_manager->remove_chunk(chunk); 450 assert(chunk->next() == NULL && 451 chunk->prev() == NULL, 452 "Was not removed from its list"); 453 chunk = (Metachunk*) next; 454 } 455 } 456 457 #ifdef ASSERT 458 uintx VirtualSpaceNode::container_count_slow() { 459 uintx count = 0; 460 Metachunk* chunk = first_chunk(); 461 Metachunk* invalid_chunk = (Metachunk*) top(); 462 while (chunk < invalid_chunk ) { 463 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 464 // Don't count the chunks on the free lists. Those are 465 // still part of the VirtualSpaceNode but not currently 466 // counted. 467 if (!chunk->is_tagged_free()) { 468 count++; 469 } 470 chunk = (Metachunk*) next; 471 } 472 return count; 473 } 474 #endif 475 476 // List of VirtualSpaces for metadata allocation. 477 class VirtualSpaceList : public CHeapObj<mtClass> { 478 friend class VirtualSpaceNode; 479 480 enum VirtualSpaceSizes { 481 VirtualSpaceSize = 256 * K 482 }; 483 484 // Head of the list 485 VirtualSpaceNode* _virtual_space_list; 486 // virtual space currently being used for allocations 487 VirtualSpaceNode* _current_virtual_space; 488 489 // Is this VirtualSpaceList used for the compressed class space 490 bool _is_class; 491 492 // Sum of reserved and committed memory in the virtual spaces 493 size_t _reserved_words; 494 size_t _committed_words; 495 496 // Number of virtual spaces 497 size_t _virtual_space_count; 498 499 ~VirtualSpaceList(); 500 501 VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; } 502 503 void set_virtual_space_list(VirtualSpaceNode* v) { 504 _virtual_space_list = v; 505 } 506 void set_current_virtual_space(VirtualSpaceNode* v) { 507 _current_virtual_space = v; 508 } 509 510 void link_vs(VirtualSpaceNode* new_entry); 511 512 // Get another virtual space and add it to the list. This 513 // is typically prompted by a failed attempt to allocate a chunk 514 // and is typically followed by the allocation of a chunk. 515 bool create_new_virtual_space(size_t vs_word_size); 516 517 // Chunk up the unused committed space in the current 518 // virtual space and add the chunks to the free list. 519 void retire_current_virtual_space(); 520 521 public: 522 VirtualSpaceList(size_t word_size); 523 VirtualSpaceList(ReservedSpace rs); 524 525 size_t free_bytes(); 526 527 Metachunk* get_new_chunk(size_t word_size, 528 size_t grow_chunks_by_words, 529 size_t medium_chunk_bunch); 530 531 bool expand_node_by(VirtualSpaceNode* node, 532 size_t min_words, 533 size_t preferred_words); 534 535 bool expand_by(size_t min_words, 536 size_t preferred_words); 537 538 VirtualSpaceNode* current_virtual_space() { 539 return _current_virtual_space; 540 } 541 542 bool is_class() const { return _is_class; } 543 544 bool initialization_succeeded() { return _virtual_space_list != NULL; } 545 546 size_t reserved_words() { return _reserved_words; } 547 size_t reserved_bytes() { return reserved_words() * BytesPerWord; } 548 size_t committed_words() { return _committed_words; } 549 size_t committed_bytes() { return committed_words() * BytesPerWord; } 550 551 void inc_reserved_words(size_t v); 552 void dec_reserved_words(size_t v); 553 void inc_committed_words(size_t v); 554 void dec_committed_words(size_t v); 555 void inc_virtual_space_count(); 556 void dec_virtual_space_count(); 557 558 bool contains(const void* ptr); 559 560 // Unlink empty VirtualSpaceNodes and free it. 561 void purge(ChunkManager* chunk_manager); 562 563 void print_on(outputStream* st) const; 564 565 class VirtualSpaceListIterator : public StackObj { 566 VirtualSpaceNode* _virtual_spaces; 567 public: 568 VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) : 569 _virtual_spaces(virtual_spaces) {} 570 571 bool repeat() { 572 return _virtual_spaces != NULL; 573 } 574 575 VirtualSpaceNode* get_next() { 576 VirtualSpaceNode* result = _virtual_spaces; 577 if (_virtual_spaces != NULL) { 578 _virtual_spaces = _virtual_spaces->next(); 579 } 580 return result; 581 } 582 }; 583 }; 584 585 class Metadebug : AllStatic { 586 // Debugging support for Metaspaces 587 static int _allocation_fail_alot_count; 588 589 public: 590 591 static void init_allocation_fail_alot_count(); 592 #ifdef ASSERT 593 static bool test_metadata_failure(); 594 #endif 595 }; 596 597 int Metadebug::_allocation_fail_alot_count = 0; 598 599 // SpaceManager - used by Metaspace to handle allocations 600 class SpaceManager : public CHeapObj<mtClass> { 601 friend class Metaspace; 602 friend class Metadebug; 603 604 private: 605 606 // protects allocations 607 Mutex* const _lock; 608 609 // Type of metadata allocated. 610 Metaspace::MetadataType _mdtype; 611 612 // List of chunks in use by this SpaceManager. Allocations 613 // are done from the current chunk. The list is used for deallocating 614 // chunks when the SpaceManager is freed. 615 Metachunk* _chunks_in_use[NumberOfInUseLists]; 616 Metachunk* _current_chunk; 617 618 // Maximum number of small chunks to allocate to a SpaceManager 619 static uint const _small_chunk_limit; 620 621 // Sum of all space in allocated chunks 622 size_t _allocated_blocks_words; 623 624 // Sum of all allocated chunks 625 size_t _allocated_chunks_words; 626 size_t _allocated_chunks_count; 627 628 // Free lists of blocks are per SpaceManager since they 629 // are assumed to be in chunks in use by the SpaceManager 630 // and all chunks in use by a SpaceManager are freed when 631 // the class loader using the SpaceManager is collected. 632 BlockFreelist _block_freelists; 633 634 // protects virtualspace and chunk expansions 635 static const char* _expand_lock_name; 636 static const int _expand_lock_rank; 637 static Mutex* const _expand_lock; 638 639 private: 640 // Accessors 641 Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; } 642 void set_chunks_in_use(ChunkIndex index, Metachunk* v) { 643 _chunks_in_use[index] = v; 644 } 645 646 BlockFreelist* block_freelists() const { 647 return (BlockFreelist*) &_block_freelists; 648 } 649 650 Metaspace::MetadataType mdtype() { return _mdtype; } 651 652 VirtualSpaceList* vs_list() const { return Metaspace::get_space_list(_mdtype); } 653 ChunkManager* chunk_manager() const { return Metaspace::get_chunk_manager(_mdtype); } 654 655 Metachunk* current_chunk() const { return _current_chunk; } 656 void set_current_chunk(Metachunk* v) { 657 _current_chunk = v; 658 } 659 660 Metachunk* find_current_chunk(size_t word_size); 661 662 // Add chunk to the list of chunks in use 663 void add_chunk(Metachunk* v, bool make_current); 664 void retire_current_chunk(); 665 666 Mutex* lock() const { return _lock; } 667 668 const char* chunk_size_name(ChunkIndex index) const; 669 670 protected: 671 void initialize(); 672 673 public: 674 SpaceManager(Metaspace::MetadataType mdtype, 675 Mutex* lock); 676 ~SpaceManager(); 677 678 enum ChunkMultiples { 679 MediumChunkMultiple = 4 680 }; 681 682 bool is_class() { return _mdtype == Metaspace::ClassType; } 683 684 // Accessors 685 size_t specialized_chunk_size() { return (size_t) is_class() ? ClassSpecializedChunk : SpecializedChunk; } 686 size_t small_chunk_size() { return (size_t) is_class() ? ClassSmallChunk : SmallChunk; } 687 size_t medium_chunk_size() { return (size_t) is_class() ? ClassMediumChunk : MediumChunk; } 688 size_t medium_chunk_bunch() { return medium_chunk_size() * MediumChunkMultiple; } 689 690 size_t smallest_chunk_size() { return specialized_chunk_size(); } 691 692 size_t allocated_blocks_words() const { return _allocated_blocks_words; } 693 size_t allocated_blocks_bytes() const { return _allocated_blocks_words * BytesPerWord; } 694 size_t allocated_chunks_words() const { return _allocated_chunks_words; } 695 size_t allocated_chunks_bytes() const { return _allocated_chunks_words * BytesPerWord; } 696 size_t allocated_chunks_count() const { return _allocated_chunks_count; } 697 698 bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); } 699 700 static Mutex* expand_lock() { return _expand_lock; } 701 702 // Increment the per Metaspace and global running sums for Metachunks 703 // by the given size. This is used when a Metachunk to added to 704 // the in-use list. 705 void inc_size_metrics(size_t words); 706 // Increment the per Metaspace and global running sums Metablocks by the given 707 // size. This is used when a Metablock is allocated. 708 void inc_used_metrics(size_t words); 709 // Delete the portion of the running sums for this SpaceManager. That is, 710 // the globals running sums for the Metachunks and Metablocks are 711 // decremented for all the Metachunks in-use by this SpaceManager. 712 void dec_total_from_size_metrics(); 713 714 // Set the sizes for the initial chunks. 715 void get_initial_chunk_sizes(Metaspace::MetaspaceType type, 716 size_t* chunk_word_size, 717 size_t* class_chunk_word_size); 718 719 size_t sum_capacity_in_chunks_in_use() const; 720 size_t sum_used_in_chunks_in_use() const; 721 size_t sum_free_in_chunks_in_use() const; 722 size_t sum_waste_in_chunks_in_use() const; 723 size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const; 724 725 size_t sum_count_in_chunks_in_use(); 726 size_t sum_count_in_chunks_in_use(ChunkIndex i); 727 728 Metachunk* get_new_chunk(size_t word_size, size_t grow_chunks_by_words); 729 730 // Block allocation and deallocation. 731 // Allocates a block from the current chunk 732 MetaWord* allocate(size_t word_size); 733 // Allocates a block from a small chunk 734 MetaWord* get_small_chunk_and_allocate(size_t word_size); 735 736 // Helper for allocations 737 MetaWord* allocate_work(size_t word_size); 738 739 // Returns a block to the per manager freelist 740 void deallocate(MetaWord* p, size_t word_size); 741 742 // Based on the allocation size and a minimum chunk size, 743 // returned chunk size (for expanding space for chunk allocation). 744 size_t calc_chunk_size(size_t allocation_word_size); 745 746 // Called when an allocation from the current chunk fails. 747 // Gets a new chunk (may require getting a new virtual space), 748 // and allocates from that chunk. 749 MetaWord* grow_and_allocate(size_t word_size); 750 751 // Notify memory usage to MemoryService. 752 void track_metaspace_memory_usage(); 753 754 // debugging support. 755 756 void dump(outputStream* const out) const; 757 void print_on(outputStream* st) const; 758 void locked_print_chunks_in_use_on(outputStream* st) const; 759 760 void verify(); 761 void verify_chunk_size(Metachunk* chunk); 762 NOT_PRODUCT(void mangle_freed_chunks();) 763 #ifdef ASSERT 764 void verify_allocated_blocks_words(); 765 #endif 766 767 size_t get_raw_word_size(size_t word_size) { 768 size_t byte_size = word_size * BytesPerWord; 769 770 size_t raw_bytes_size = MAX2(byte_size, sizeof(Metablock)); 771 raw_bytes_size = align_size_up(raw_bytes_size, Metachunk::object_alignment()); 772 773 size_t raw_word_size = raw_bytes_size / BytesPerWord; 774 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem"); 775 776 return raw_word_size; 777 } 778 }; 779 780 uint const SpaceManager::_small_chunk_limit = 4; 781 782 const char* SpaceManager::_expand_lock_name = 783 "SpaceManager chunk allocation lock"; 784 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1; 785 Mutex* const SpaceManager::_expand_lock = 786 new Mutex(SpaceManager::_expand_lock_rank, 787 SpaceManager::_expand_lock_name, 788 Mutex::_allow_vm_block_flag, 789 Monitor::_safepoint_check_never); 790 791 void VirtualSpaceNode::inc_container_count() { 792 assert_lock_strong(SpaceManager::expand_lock()); 793 _container_count++; 794 } 795 796 void VirtualSpaceNode::dec_container_count() { 797 assert_lock_strong(SpaceManager::expand_lock()); 798 _container_count--; 799 } 800 801 #ifdef ASSERT 802 void VirtualSpaceNode::verify_container_count() { 803 assert(_container_count == container_count_slow(), 804 "Inconsistency in container_count _container_count " UINTX_FORMAT 805 " container_count_slow() " UINTX_FORMAT, _container_count, container_count_slow()); 806 } 807 #endif 808 809 // BlockFreelist methods 810 811 BlockFreelist::BlockFreelist() : _dictionary(new BlockTreeDictionary()) {} 812 813 BlockFreelist::~BlockFreelist() { 814 LogHandle(gc, metaspace, freelist) log; 815 if (log.is_trace()) { 816 ResourceMark rm; 817 dictionary()->print_free_lists(log.trace_stream()); 818 } 819 delete _dictionary; 820 } 821 822 void BlockFreelist::return_block(MetaWord* p, size_t word_size) { 823 Metablock* free_chunk = ::new (p) Metablock(word_size); 824 dictionary()->return_chunk(free_chunk); 825 } 826 827 MetaWord* BlockFreelist::get_block(size_t word_size) { 828 if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::min_size()) { 829 // Dark matter. Too small for dictionary. 830 return NULL; 831 } 832 833 Metablock* free_block = 834 dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::atLeast); 835 if (free_block == NULL) { 836 return NULL; 837 } 838 839 const size_t block_size = free_block->size(); 840 if (block_size > WasteMultiplier * word_size) { 841 return_block((MetaWord*)free_block, block_size); 842 return NULL; 843 } 844 845 MetaWord* new_block = (MetaWord*)free_block; 846 assert(block_size >= word_size, "Incorrect size of block from freelist"); 847 const size_t unused = block_size - word_size; 848 if (unused >= TreeChunk<Metablock, FreeList<Metablock> >::min_size()) { 849 return_block(new_block + word_size, unused); 850 } 851 852 return new_block; 853 } 854 855 void BlockFreelist::print_on(outputStream* st) const { 856 dictionary()->print_free_lists(st); 857 } 858 859 // VirtualSpaceNode methods 860 861 VirtualSpaceNode::~VirtualSpaceNode() { 862 _rs.release(); 863 #ifdef ASSERT 864 size_t word_size = sizeof(*this) / BytesPerWord; 865 Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1); 866 #endif 867 } 868 869 size_t VirtualSpaceNode::used_words_in_vs() const { 870 return pointer_delta(top(), bottom(), sizeof(MetaWord)); 871 } 872 873 // Space committed in the VirtualSpace 874 size_t VirtualSpaceNode::capacity_words_in_vs() const { 875 return pointer_delta(end(), bottom(), sizeof(MetaWord)); 876 } 877 878 size_t VirtualSpaceNode::free_words_in_vs() const { 879 return pointer_delta(end(), top(), sizeof(MetaWord)); 880 } 881 882 // Allocates the chunk from the virtual space only. 883 // This interface is also used internally for debugging. Not all 884 // chunks removed here are necessarily used for allocation. 885 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) { 886 // Bottom of the new chunk 887 MetaWord* chunk_limit = top(); 888 assert(chunk_limit != NULL, "Not safe to call this method"); 889 890 // The virtual spaces are always expanded by the 891 // commit granularity to enforce the following condition. 892 // Without this the is_available check will not work correctly. 893 assert(_virtual_space.committed_size() == _virtual_space.actual_committed_size(), 894 "The committed memory doesn't match the expanded memory."); 895 896 if (!is_available(chunk_word_size)) { 897 LogHandle(gc, metaspace, freelist) log; 898 log.debug("VirtualSpaceNode::take_from_committed() not available " SIZE_FORMAT " words ", chunk_word_size); 899 // Dump some information about the virtual space that is nearly full 900 ResourceMark rm; 901 print_on(log.debug_stream()); 902 return NULL; 903 } 904 905 // Take the space (bump top on the current virtual space). 906 inc_top(chunk_word_size); 907 908 // Initialize the chunk 909 Metachunk* result = ::new (chunk_limit) Metachunk(chunk_word_size, this); 910 return result; 911 } 912 913 914 // Expand the virtual space (commit more of the reserved space) 915 bool VirtualSpaceNode::expand_by(size_t min_words, size_t preferred_words) { 916 size_t min_bytes = min_words * BytesPerWord; 917 size_t preferred_bytes = preferred_words * BytesPerWord; 918 919 size_t uncommitted = virtual_space()->reserved_size() - virtual_space()->actual_committed_size(); 920 921 if (uncommitted < min_bytes) { 922 return false; 923 } 924 925 size_t commit = MIN2(preferred_bytes, uncommitted); 926 bool result = virtual_space()->expand_by(commit, false); 927 928 assert(result, "Failed to commit memory"); 929 930 return result; 931 } 932 933 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) { 934 assert_lock_strong(SpaceManager::expand_lock()); 935 Metachunk* result = take_from_committed(chunk_word_size); 936 if (result != NULL) { 937 inc_container_count(); 938 } 939 return result; 940 } 941 942 bool VirtualSpaceNode::initialize() { 943 944 if (!_rs.is_reserved()) { 945 return false; 946 } 947 948 // These are necessary restriction to make sure that the virtual space always 949 // grows in steps of Metaspace::commit_alignment(). If both base and size are 950 // aligned only the middle alignment of the VirtualSpace is used. 951 assert_is_ptr_aligned(_rs.base(), Metaspace::commit_alignment()); 952 assert_is_size_aligned(_rs.size(), Metaspace::commit_alignment()); 953 954 // ReservedSpaces marked as special will have the entire memory 955 // pre-committed. Setting a committed size will make sure that 956 // committed_size and actual_committed_size agrees. 957 size_t pre_committed_size = _rs.special() ? _rs.size() : 0; 958 959 bool result = virtual_space()->initialize_with_granularity(_rs, pre_committed_size, 960 Metaspace::commit_alignment()); 961 if (result) { 962 assert(virtual_space()->committed_size() == virtual_space()->actual_committed_size(), 963 "Checking that the pre-committed memory was registered by the VirtualSpace"); 964 965 set_top((MetaWord*)virtual_space()->low()); 966 set_reserved(MemRegion((HeapWord*)_rs.base(), 967 (HeapWord*)(_rs.base() + _rs.size()))); 968 969 assert(reserved()->start() == (HeapWord*) _rs.base(), 970 "Reserved start was not set properly " PTR_FORMAT 971 " != " PTR_FORMAT, p2i(reserved()->start()), p2i(_rs.base())); 972 assert(reserved()->word_size() == _rs.size() / BytesPerWord, 973 "Reserved size was not set properly " SIZE_FORMAT 974 " != " SIZE_FORMAT, reserved()->word_size(), 975 _rs.size() / BytesPerWord); 976 } 977 978 return result; 979 } 980 981 void VirtualSpaceNode::print_on(outputStream* st) const { 982 size_t used = used_words_in_vs(); 983 size_t capacity = capacity_words_in_vs(); 984 VirtualSpace* vs = virtual_space(); 985 st->print_cr(" space @ " PTR_FORMAT " " SIZE_FORMAT "K, " SIZE_FORMAT_W(3) "%% used " 986 "[" PTR_FORMAT ", " PTR_FORMAT ", " 987 PTR_FORMAT ", " PTR_FORMAT ")", 988 p2i(vs), capacity / K, 989 capacity == 0 ? 0 : used * 100 / capacity, 990 p2i(bottom()), p2i(top()), p2i(end()), 991 p2i(vs->high_boundary())); 992 } 993 994 #ifdef ASSERT 995 void VirtualSpaceNode::mangle() { 996 size_t word_size = capacity_words_in_vs(); 997 Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1); 998 } 999 #endif // ASSERT 1000 1001 // VirtualSpaceList methods 1002 // Space allocated from the VirtualSpace 1003 1004 VirtualSpaceList::~VirtualSpaceList() { 1005 VirtualSpaceListIterator iter(virtual_space_list()); 1006 while (iter.repeat()) { 1007 VirtualSpaceNode* vsl = iter.get_next(); 1008 delete vsl; 1009 } 1010 } 1011 1012 void VirtualSpaceList::inc_reserved_words(size_t v) { 1013 assert_lock_strong(SpaceManager::expand_lock()); 1014 _reserved_words = _reserved_words + v; 1015 } 1016 void VirtualSpaceList::dec_reserved_words(size_t v) { 1017 assert_lock_strong(SpaceManager::expand_lock()); 1018 _reserved_words = _reserved_words - v; 1019 } 1020 1021 #define assert_committed_below_limit() \ 1022 assert(MetaspaceAux::committed_bytes() <= MaxMetaspaceSize, \ 1023 "Too much committed memory. Committed: " SIZE_FORMAT \ 1024 " limit (MaxMetaspaceSize): " SIZE_FORMAT, \ 1025 MetaspaceAux::committed_bytes(), MaxMetaspaceSize); 1026 1027 void VirtualSpaceList::inc_committed_words(size_t v) { 1028 assert_lock_strong(SpaceManager::expand_lock()); 1029 _committed_words = _committed_words + v; 1030 1031 assert_committed_below_limit(); 1032 } 1033 void VirtualSpaceList::dec_committed_words(size_t v) { 1034 assert_lock_strong(SpaceManager::expand_lock()); 1035 _committed_words = _committed_words - v; 1036 1037 assert_committed_below_limit(); 1038 } 1039 1040 void VirtualSpaceList::inc_virtual_space_count() { 1041 assert_lock_strong(SpaceManager::expand_lock()); 1042 _virtual_space_count++; 1043 } 1044 void VirtualSpaceList::dec_virtual_space_count() { 1045 assert_lock_strong(SpaceManager::expand_lock()); 1046 _virtual_space_count--; 1047 } 1048 1049 void ChunkManager::remove_chunk(Metachunk* chunk) { 1050 size_t word_size = chunk->word_size(); 1051 ChunkIndex index = list_index(word_size); 1052 if (index != HumongousIndex) { 1053 free_chunks(index)->remove_chunk(chunk); 1054 } else { 1055 humongous_dictionary()->remove_chunk(chunk); 1056 } 1057 1058 // Chunk is being removed from the chunks free list. 1059 dec_free_chunks_total(chunk->word_size()); 1060 } 1061 1062 // Walk the list of VirtualSpaceNodes and delete 1063 // nodes with a 0 container_count. Remove Metachunks in 1064 // the node from their respective freelists. 1065 void VirtualSpaceList::purge(ChunkManager* chunk_manager) { 1066 assert(SafepointSynchronize::is_at_safepoint(), "must be called at safepoint for contains to work"); 1067 assert_lock_strong(SpaceManager::expand_lock()); 1068 // Don't use a VirtualSpaceListIterator because this 1069 // list is being changed and a straightforward use of an iterator is not safe. 1070 VirtualSpaceNode* purged_vsl = NULL; 1071 VirtualSpaceNode* prev_vsl = virtual_space_list(); 1072 VirtualSpaceNode* next_vsl = prev_vsl; 1073 while (next_vsl != NULL) { 1074 VirtualSpaceNode* vsl = next_vsl; 1075 DEBUG_ONLY(vsl->verify_container_count();) 1076 next_vsl = vsl->next(); 1077 // Don't free the current virtual space since it will likely 1078 // be needed soon. 1079 if (vsl->container_count() == 0 && vsl != current_virtual_space()) { 1080 // Unlink it from the list 1081 if (prev_vsl == vsl) { 1082 // This is the case of the current node being the first node. 1083 assert(vsl == virtual_space_list(), "Expected to be the first node"); 1084 set_virtual_space_list(vsl->next()); 1085 } else { 1086 prev_vsl->set_next(vsl->next()); 1087 } 1088 1089 vsl->purge(chunk_manager); 1090 dec_reserved_words(vsl->reserved_words()); 1091 dec_committed_words(vsl->committed_words()); 1092 dec_virtual_space_count(); 1093 purged_vsl = vsl; 1094 delete vsl; 1095 } else { 1096 prev_vsl = vsl; 1097 } 1098 } 1099 #ifdef ASSERT 1100 if (purged_vsl != NULL) { 1101 // List should be stable enough to use an iterator here. 1102 VirtualSpaceListIterator iter(virtual_space_list()); 1103 while (iter.repeat()) { 1104 VirtualSpaceNode* vsl = iter.get_next(); 1105 assert(vsl != purged_vsl, "Purge of vsl failed"); 1106 } 1107 } 1108 #endif 1109 } 1110 1111 1112 // This function looks at the mmap regions in the metaspace without locking. 1113 // The chunks are added with store ordering and not deleted except for at 1114 // unloading time during a safepoint. 1115 bool VirtualSpaceList::contains(const void* ptr) { 1116 // List should be stable enough to use an iterator here because removing virtual 1117 // space nodes is only allowed at a safepoint. 1118 VirtualSpaceListIterator iter(virtual_space_list()); 1119 while (iter.repeat()) { 1120 VirtualSpaceNode* vsn = iter.get_next(); 1121 if (vsn->contains(ptr)) { 1122 return true; 1123 } 1124 } 1125 return false; 1126 } 1127 1128 void VirtualSpaceList::retire_current_virtual_space() { 1129 assert_lock_strong(SpaceManager::expand_lock()); 1130 1131 VirtualSpaceNode* vsn = current_virtual_space(); 1132 1133 ChunkManager* cm = is_class() ? Metaspace::chunk_manager_class() : 1134 Metaspace::chunk_manager_metadata(); 1135 1136 vsn->retire(cm); 1137 } 1138 1139 void VirtualSpaceNode::retire(ChunkManager* chunk_manager) { 1140 DEBUG_ONLY(verify_container_count();) 1141 for (int i = (int)MediumIndex; i >= (int)ZeroIndex; --i) { 1142 ChunkIndex index = (ChunkIndex)i; 1143 size_t chunk_size = chunk_manager->free_chunks(index)->size(); 1144 1145 while (free_words_in_vs() >= chunk_size) { 1146 Metachunk* chunk = get_chunk_vs(chunk_size); 1147 assert(chunk != NULL, "allocation should have been successful"); 1148 1149 chunk_manager->return_chunks(index, chunk); 1150 chunk_manager->inc_free_chunks_total(chunk_size); 1151 } 1152 DEBUG_ONLY(verify_container_count();) 1153 } 1154 assert(free_words_in_vs() == 0, "should be empty now"); 1155 } 1156 1157 VirtualSpaceList::VirtualSpaceList(size_t word_size) : 1158 _is_class(false), 1159 _virtual_space_list(NULL), 1160 _current_virtual_space(NULL), 1161 _reserved_words(0), 1162 _committed_words(0), 1163 _virtual_space_count(0) { 1164 MutexLockerEx cl(SpaceManager::expand_lock(), 1165 Mutex::_no_safepoint_check_flag); 1166 create_new_virtual_space(word_size); 1167 } 1168 1169 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) : 1170 _is_class(true), 1171 _virtual_space_list(NULL), 1172 _current_virtual_space(NULL), 1173 _reserved_words(0), 1174 _committed_words(0), 1175 _virtual_space_count(0) { 1176 MutexLockerEx cl(SpaceManager::expand_lock(), 1177 Mutex::_no_safepoint_check_flag); 1178 VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs); 1179 bool succeeded = class_entry->initialize(); 1180 if (succeeded) { 1181 link_vs(class_entry); 1182 } 1183 } 1184 1185 size_t VirtualSpaceList::free_bytes() { 1186 return virtual_space_list()->free_words_in_vs() * BytesPerWord; 1187 } 1188 1189 // Allocate another meta virtual space and add it to the list. 1190 bool VirtualSpaceList::create_new_virtual_space(size_t vs_word_size) { 1191 assert_lock_strong(SpaceManager::expand_lock()); 1192 1193 if (is_class()) { 1194 assert(false, "We currently don't support more than one VirtualSpace for" 1195 " the compressed class space. The initialization of the" 1196 " CCS uses another code path and should not hit this path."); 1197 return false; 1198 } 1199 1200 if (vs_word_size == 0) { 1201 assert(false, "vs_word_size should always be at least _reserve_alignment large."); 1202 return false; 1203 } 1204 1205 // Reserve the space 1206 size_t vs_byte_size = vs_word_size * BytesPerWord; 1207 assert_is_size_aligned(vs_byte_size, Metaspace::reserve_alignment()); 1208 1209 // Allocate the meta virtual space and initialize it. 1210 VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size); 1211 if (!new_entry->initialize()) { 1212 delete new_entry; 1213 return false; 1214 } else { 1215 assert(new_entry->reserved_words() == vs_word_size, 1216 "Reserved memory size differs from requested memory size"); 1217 // ensure lock-free iteration sees fully initialized node 1218 OrderAccess::storestore(); 1219 link_vs(new_entry); 1220 return true; 1221 } 1222 } 1223 1224 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry) { 1225 if (virtual_space_list() == NULL) { 1226 set_virtual_space_list(new_entry); 1227 } else { 1228 current_virtual_space()->set_next(new_entry); 1229 } 1230 set_current_virtual_space(new_entry); 1231 inc_reserved_words(new_entry->reserved_words()); 1232 inc_committed_words(new_entry->committed_words()); 1233 inc_virtual_space_count(); 1234 #ifdef ASSERT 1235 new_entry->mangle(); 1236 #endif 1237 if (log_is_enabled(Trace, gc, metaspace)) { 1238 LogHandle(gc, metaspace) log; 1239 VirtualSpaceNode* vsl = current_virtual_space(); 1240 ResourceMark rm; 1241 vsl->print_on(log.trace_stream()); 1242 } 1243 } 1244 1245 bool VirtualSpaceList::expand_node_by(VirtualSpaceNode* node, 1246 size_t min_words, 1247 size_t preferred_words) { 1248 size_t before = node->committed_words(); 1249 1250 bool result = node->expand_by(min_words, preferred_words); 1251 1252 size_t after = node->committed_words(); 1253 1254 // after and before can be the same if the memory was pre-committed. 1255 assert(after >= before, "Inconsistency"); 1256 inc_committed_words(after - before); 1257 1258 return result; 1259 } 1260 1261 bool VirtualSpaceList::expand_by(size_t min_words, size_t preferred_words) { 1262 assert_is_size_aligned(min_words, Metaspace::commit_alignment_words()); 1263 assert_is_size_aligned(preferred_words, Metaspace::commit_alignment_words()); 1264 assert(min_words <= preferred_words, "Invalid arguments"); 1265 1266 if (!MetaspaceGC::can_expand(min_words, this->is_class())) { 1267 return false; 1268 } 1269 1270 size_t allowed_expansion_words = MetaspaceGC::allowed_expansion(); 1271 if (allowed_expansion_words < min_words) { 1272 return false; 1273 } 1274 1275 size_t max_expansion_words = MIN2(preferred_words, allowed_expansion_words); 1276 1277 // Commit more memory from the the current virtual space. 1278 bool vs_expanded = expand_node_by(current_virtual_space(), 1279 min_words, 1280 max_expansion_words); 1281 if (vs_expanded) { 1282 return true; 1283 } 1284 retire_current_virtual_space(); 1285 1286 // Get another virtual space. 1287 size_t grow_vs_words = MAX2((size_t)VirtualSpaceSize, preferred_words); 1288 grow_vs_words = align_size_up(grow_vs_words, Metaspace::reserve_alignment_words()); 1289 1290 if (create_new_virtual_space(grow_vs_words)) { 1291 if (current_virtual_space()->is_pre_committed()) { 1292 // The memory was pre-committed, so we are done here. 1293 assert(min_words <= current_virtual_space()->committed_words(), 1294 "The new VirtualSpace was pre-committed, so it" 1295 "should be large enough to fit the alloc request."); 1296 return true; 1297 } 1298 1299 return expand_node_by(current_virtual_space(), 1300 min_words, 1301 max_expansion_words); 1302 } 1303 1304 return false; 1305 } 1306 1307 Metachunk* VirtualSpaceList::get_new_chunk(size_t word_size, 1308 size_t grow_chunks_by_words, 1309 size_t medium_chunk_bunch) { 1310 1311 // Allocate a chunk out of the current virtual space. 1312 Metachunk* next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words); 1313 1314 if (next != NULL) { 1315 return next; 1316 } 1317 1318 // The expand amount is currently only determined by the requested sizes 1319 // and not how much committed memory is left in the current virtual space. 1320 1321 size_t min_word_size = align_size_up(grow_chunks_by_words, Metaspace::commit_alignment_words()); 1322 size_t preferred_word_size = align_size_up(medium_chunk_bunch, Metaspace::commit_alignment_words()); 1323 if (min_word_size >= preferred_word_size) { 1324 // Can happen when humongous chunks are allocated. 1325 preferred_word_size = min_word_size; 1326 } 1327 1328 bool expanded = expand_by(min_word_size, preferred_word_size); 1329 if (expanded) { 1330 next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words); 1331 assert(next != NULL, "The allocation was expected to succeed after the expansion"); 1332 } 1333 1334 return next; 1335 } 1336 1337 void VirtualSpaceList::print_on(outputStream* st) const { 1338 VirtualSpaceListIterator iter(virtual_space_list()); 1339 while (iter.repeat()) { 1340 VirtualSpaceNode* node = iter.get_next(); 1341 node->print_on(st); 1342 } 1343 } 1344 1345 // MetaspaceGC methods 1346 1347 // VM_CollectForMetadataAllocation is the vm operation used to GC. 1348 // Within the VM operation after the GC the attempt to allocate the metadata 1349 // should succeed. If the GC did not free enough space for the metaspace 1350 // allocation, the HWM is increased so that another virtualspace will be 1351 // allocated for the metadata. With perm gen the increase in the perm 1352 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The 1353 // metaspace policy uses those as the small and large steps for the HWM. 1354 // 1355 // After the GC the compute_new_size() for MetaspaceGC is called to 1356 // resize the capacity of the metaspaces. The current implementation 1357 // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used 1358 // to resize the Java heap by some GC's. New flags can be implemented 1359 // if really needed. MinMetaspaceFreeRatio is used to calculate how much 1360 // free space is desirable in the metaspace capacity to decide how much 1361 // to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much 1362 // free space is desirable in the metaspace capacity before decreasing 1363 // the HWM. 1364 1365 // Calculate the amount to increase the high water mark (HWM). 1366 // Increase by a minimum amount (MinMetaspaceExpansion) so that 1367 // another expansion is not requested too soon. If that is not 1368 // enough to satisfy the allocation, increase by MaxMetaspaceExpansion. 1369 // If that is still not enough, expand by the size of the allocation 1370 // plus some. 1371 size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) { 1372 size_t min_delta = MinMetaspaceExpansion; 1373 size_t max_delta = MaxMetaspaceExpansion; 1374 size_t delta = align_size_up(bytes, Metaspace::commit_alignment()); 1375 1376 if (delta <= min_delta) { 1377 delta = min_delta; 1378 } else if (delta <= max_delta) { 1379 // Don't want to hit the high water mark on the next 1380 // allocation so make the delta greater than just enough 1381 // for this allocation. 1382 delta = max_delta; 1383 } else { 1384 // This allocation is large but the next ones are probably not 1385 // so increase by the minimum. 1386 delta = delta + min_delta; 1387 } 1388 1389 assert_is_size_aligned(delta, Metaspace::commit_alignment()); 1390 1391 return delta; 1392 } 1393 1394 size_t MetaspaceGC::capacity_until_GC() { 1395 size_t value = (size_t)OrderAccess::load_ptr_acquire(&_capacity_until_GC); 1396 assert(value >= MetaspaceSize, "Not initialized properly?"); 1397 return value; 1398 } 1399 1400 bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC) { 1401 assert_is_size_aligned(v, Metaspace::commit_alignment()); 1402 1403 size_t capacity_until_GC = (size_t) _capacity_until_GC; 1404 size_t new_value = capacity_until_GC + v; 1405 1406 if (new_value < capacity_until_GC) { 1407 // The addition wrapped around, set new_value to aligned max value. 1408 new_value = align_size_down(max_uintx, Metaspace::commit_alignment()); 1409 } 1410 1411 intptr_t expected = (intptr_t) capacity_until_GC; 1412 intptr_t actual = Atomic::cmpxchg_ptr((intptr_t) new_value, &_capacity_until_GC, expected); 1413 1414 if (expected != actual) { 1415 return false; 1416 } 1417 1418 if (new_cap_until_GC != NULL) { 1419 *new_cap_until_GC = new_value; 1420 } 1421 if (old_cap_until_GC != NULL) { 1422 *old_cap_until_GC = capacity_until_GC; 1423 } 1424 return true; 1425 } 1426 1427 size_t MetaspaceGC::dec_capacity_until_GC(size_t v) { 1428 assert_is_size_aligned(v, Metaspace::commit_alignment()); 1429 1430 return (size_t)Atomic::add_ptr(-(intptr_t)v, &_capacity_until_GC); 1431 } 1432 1433 void MetaspaceGC::initialize() { 1434 // Set the high-water mark to MaxMetapaceSize during VM initializaton since 1435 // we can't do a GC during initialization. 1436 _capacity_until_GC = MaxMetaspaceSize; 1437 } 1438 1439 void MetaspaceGC::post_initialize() { 1440 // Reset the high-water mark once the VM initialization is done. 1441 _capacity_until_GC = MAX2(MetaspaceAux::committed_bytes(), MetaspaceSize); 1442 } 1443 1444 bool MetaspaceGC::can_expand(size_t word_size, bool is_class) { 1445 // Check if the compressed class space is full. 1446 if (is_class && Metaspace::using_class_space()) { 1447 size_t class_committed = MetaspaceAux::committed_bytes(Metaspace::ClassType); 1448 if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) { 1449 return false; 1450 } 1451 } 1452 1453 // Check if the user has imposed a limit on the metaspace memory. 1454 size_t committed_bytes = MetaspaceAux::committed_bytes(); 1455 if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) { 1456 return false; 1457 } 1458 1459 return true; 1460 } 1461 1462 size_t MetaspaceGC::allowed_expansion() { 1463 size_t committed_bytes = MetaspaceAux::committed_bytes(); 1464 size_t capacity_until_gc = capacity_until_GC(); 1465 1466 assert(capacity_until_gc >= committed_bytes, 1467 "capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT, 1468 capacity_until_gc, committed_bytes); 1469 1470 size_t left_until_max = MaxMetaspaceSize - committed_bytes; 1471 size_t left_until_GC = capacity_until_gc - committed_bytes; 1472 size_t left_to_commit = MIN2(left_until_GC, left_until_max); 1473 1474 return left_to_commit / BytesPerWord; 1475 } 1476 1477 void MetaspaceGC::compute_new_size() { 1478 assert(_shrink_factor <= 100, "invalid shrink factor"); 1479 uint current_shrink_factor = _shrink_factor; 1480 _shrink_factor = 0; 1481 1482 // Using committed_bytes() for used_after_gc is an overestimation, since the 1483 // chunk free lists are included in committed_bytes() and the memory in an 1484 // un-fragmented chunk free list is available for future allocations. 1485 // However, if the chunk free lists becomes fragmented, then the memory may 1486 // not be available for future allocations and the memory is therefore "in use". 1487 // Including the chunk free lists in the definition of "in use" is therefore 1488 // necessary. Not including the chunk free lists can cause capacity_until_GC to 1489 // shrink below committed_bytes() and this has caused serious bugs in the past. 1490 const size_t used_after_gc = MetaspaceAux::committed_bytes(); 1491 const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC(); 1492 1493 const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0; 1494 const double maximum_used_percentage = 1.0 - minimum_free_percentage; 1495 1496 const double min_tmp = used_after_gc / maximum_used_percentage; 1497 size_t minimum_desired_capacity = 1498 (size_t)MIN2(min_tmp, double(max_uintx)); 1499 // Don't shrink less than the initial generation size 1500 minimum_desired_capacity = MAX2(minimum_desired_capacity, 1501 MetaspaceSize); 1502 1503 log_trace(gc, metaspace)("MetaspaceGC::compute_new_size: "); 1504 log_trace(gc, metaspace)(" minimum_free_percentage: %6.2f maximum_used_percentage: %6.2f", 1505 minimum_free_percentage, maximum_used_percentage); 1506 log_trace(gc, metaspace)(" used_after_gc : %6.1fKB", used_after_gc / (double) K); 1507 1508 1509 size_t shrink_bytes = 0; 1510 if (capacity_until_GC < minimum_desired_capacity) { 1511 // If we have less capacity below the metaspace HWM, then 1512 // increment the HWM. 1513 size_t expand_bytes = minimum_desired_capacity - capacity_until_GC; 1514 expand_bytes = align_size_up(expand_bytes, Metaspace::commit_alignment()); 1515 // Don't expand unless it's significant 1516 if (expand_bytes >= MinMetaspaceExpansion) { 1517 size_t new_capacity_until_GC = 0; 1518 bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC); 1519 assert(succeeded, "Should always succesfully increment HWM when at safepoint"); 1520 1521 Metaspace::tracer()->report_gc_threshold(capacity_until_GC, 1522 new_capacity_until_GC, 1523 MetaspaceGCThresholdUpdater::ComputeNewSize); 1524 log_trace(gc, metaspace)(" expanding: minimum_desired_capacity: %6.1fKB expand_bytes: %6.1fKB MinMetaspaceExpansion: %6.1fKB new metaspace HWM: %6.1fKB", 1525 minimum_desired_capacity / (double) K, 1526 expand_bytes / (double) K, 1527 MinMetaspaceExpansion / (double) K, 1528 new_capacity_until_GC / (double) K); 1529 } 1530 return; 1531 } 1532 1533 // No expansion, now see if we want to shrink 1534 // We would never want to shrink more than this 1535 assert(capacity_until_GC >= minimum_desired_capacity, 1536 SIZE_FORMAT " >= " SIZE_FORMAT, 1537 capacity_until_GC, minimum_desired_capacity); 1538 size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity; 1539 1540 // Should shrinking be considered? 1541 if (MaxMetaspaceFreeRatio < 100) { 1542 const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0; 1543 const double minimum_used_percentage = 1.0 - maximum_free_percentage; 1544 const double max_tmp = used_after_gc / minimum_used_percentage; 1545 size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx)); 1546 maximum_desired_capacity = MAX2(maximum_desired_capacity, 1547 MetaspaceSize); 1548 log_trace(gc, metaspace)(" maximum_free_percentage: %6.2f minimum_used_percentage: %6.2f", 1549 maximum_free_percentage, minimum_used_percentage); 1550 log_trace(gc, metaspace)(" minimum_desired_capacity: %6.1fKB maximum_desired_capacity: %6.1fKB", 1551 minimum_desired_capacity / (double) K, maximum_desired_capacity / (double) K); 1552 1553 assert(minimum_desired_capacity <= maximum_desired_capacity, 1554 "sanity check"); 1555 1556 if (capacity_until_GC > maximum_desired_capacity) { 1557 // Capacity too large, compute shrinking size 1558 shrink_bytes = capacity_until_GC - maximum_desired_capacity; 1559 // We don't want shrink all the way back to initSize if people call 1560 // System.gc(), because some programs do that between "phases" and then 1561 // we'd just have to grow the heap up again for the next phase. So we 1562 // damp the shrinking: 0% on the first call, 10% on the second call, 40% 1563 // on the third call, and 100% by the fourth call. But if we recompute 1564 // size without shrinking, it goes back to 0%. 1565 shrink_bytes = shrink_bytes / 100 * current_shrink_factor; 1566 1567 shrink_bytes = align_size_down(shrink_bytes, Metaspace::commit_alignment()); 1568 1569 assert(shrink_bytes <= max_shrink_bytes, 1570 "invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT, 1571 shrink_bytes, max_shrink_bytes); 1572 if (current_shrink_factor == 0) { 1573 _shrink_factor = 10; 1574 } else { 1575 _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100); 1576 } 1577 log_trace(gc, metaspace)(" shrinking: initSize: %.1fK maximum_desired_capacity: %.1fK", 1578 MetaspaceSize / (double) K, maximum_desired_capacity / (double) K); 1579 log_trace(gc, metaspace)(" shrink_bytes: %.1fK current_shrink_factor: %d new shrink factor: %d MinMetaspaceExpansion: %.1fK", 1580 shrink_bytes / (double) K, current_shrink_factor, _shrink_factor, MinMetaspaceExpansion / (double) K); 1581 } 1582 } 1583 1584 // Don't shrink unless it's significant 1585 if (shrink_bytes >= MinMetaspaceExpansion && 1586 ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) { 1587 size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes); 1588 Metaspace::tracer()->report_gc_threshold(capacity_until_GC, 1589 new_capacity_until_GC, 1590 MetaspaceGCThresholdUpdater::ComputeNewSize); 1591 } 1592 } 1593 1594 // Metadebug methods 1595 1596 void Metadebug::init_allocation_fail_alot_count() { 1597 if (MetadataAllocationFailALot) { 1598 _allocation_fail_alot_count = 1599 1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0)); 1600 } 1601 } 1602 1603 #ifdef ASSERT 1604 bool Metadebug::test_metadata_failure() { 1605 if (MetadataAllocationFailALot && 1606 Threads::is_vm_complete()) { 1607 if (_allocation_fail_alot_count > 0) { 1608 _allocation_fail_alot_count--; 1609 } else { 1610 log_trace(gc, metaspace, freelist)("Metadata allocation failing for MetadataAllocationFailALot"); 1611 init_allocation_fail_alot_count(); 1612 return true; 1613 } 1614 } 1615 return false; 1616 } 1617 #endif 1618 1619 // ChunkManager methods 1620 1621 size_t ChunkManager::free_chunks_total_words() { 1622 return _free_chunks_total; 1623 } 1624 1625 size_t ChunkManager::free_chunks_total_bytes() { 1626 return free_chunks_total_words() * BytesPerWord; 1627 } 1628 1629 size_t ChunkManager::free_chunks_count() { 1630 #ifdef ASSERT 1631 if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) { 1632 MutexLockerEx cl(SpaceManager::expand_lock(), 1633 Mutex::_no_safepoint_check_flag); 1634 // This lock is only needed in debug because the verification 1635 // of the _free_chunks_totals walks the list of free chunks 1636 slow_locked_verify_free_chunks_count(); 1637 } 1638 #endif 1639 return _free_chunks_count; 1640 } 1641 1642 void ChunkManager::locked_verify_free_chunks_total() { 1643 assert_lock_strong(SpaceManager::expand_lock()); 1644 assert(sum_free_chunks() == _free_chunks_total, 1645 "_free_chunks_total " SIZE_FORMAT " is not the" 1646 " same as sum " SIZE_FORMAT, _free_chunks_total, 1647 sum_free_chunks()); 1648 } 1649 1650 void ChunkManager::verify_free_chunks_total() { 1651 MutexLockerEx cl(SpaceManager::expand_lock(), 1652 Mutex::_no_safepoint_check_flag); 1653 locked_verify_free_chunks_total(); 1654 } 1655 1656 void ChunkManager::locked_verify_free_chunks_count() { 1657 assert_lock_strong(SpaceManager::expand_lock()); 1658 assert(sum_free_chunks_count() == _free_chunks_count, 1659 "_free_chunks_count " SIZE_FORMAT " is not the" 1660 " same as sum " SIZE_FORMAT, _free_chunks_count, 1661 sum_free_chunks_count()); 1662 } 1663 1664 void ChunkManager::verify_free_chunks_count() { 1665 #ifdef ASSERT 1666 MutexLockerEx cl(SpaceManager::expand_lock(), 1667 Mutex::_no_safepoint_check_flag); 1668 locked_verify_free_chunks_count(); 1669 #endif 1670 } 1671 1672 void ChunkManager::verify() { 1673 MutexLockerEx cl(SpaceManager::expand_lock(), 1674 Mutex::_no_safepoint_check_flag); 1675 locked_verify(); 1676 } 1677 1678 void ChunkManager::locked_verify() { 1679 locked_verify_free_chunks_count(); 1680 locked_verify_free_chunks_total(); 1681 } 1682 1683 void ChunkManager::locked_print_free_chunks(outputStream* st) { 1684 assert_lock_strong(SpaceManager::expand_lock()); 1685 st->print_cr("Free chunk total " SIZE_FORMAT " count " SIZE_FORMAT, 1686 _free_chunks_total, _free_chunks_count); 1687 } 1688 1689 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) { 1690 assert_lock_strong(SpaceManager::expand_lock()); 1691 st->print_cr("Sum free chunk total " SIZE_FORMAT " count " SIZE_FORMAT, 1692 sum_free_chunks(), sum_free_chunks_count()); 1693 } 1694 ChunkList* ChunkManager::free_chunks(ChunkIndex index) { 1695 return &_free_chunks[index]; 1696 } 1697 1698 // These methods that sum the free chunk lists are used in printing 1699 // methods that are used in product builds. 1700 size_t ChunkManager::sum_free_chunks() { 1701 assert_lock_strong(SpaceManager::expand_lock()); 1702 size_t result = 0; 1703 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 1704 ChunkList* list = free_chunks(i); 1705 1706 if (list == NULL) { 1707 continue; 1708 } 1709 1710 result = result + list->count() * list->size(); 1711 } 1712 result = result + humongous_dictionary()->total_size(); 1713 return result; 1714 } 1715 1716 size_t ChunkManager::sum_free_chunks_count() { 1717 assert_lock_strong(SpaceManager::expand_lock()); 1718 size_t count = 0; 1719 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 1720 ChunkList* list = free_chunks(i); 1721 if (list == NULL) { 1722 continue; 1723 } 1724 count = count + list->count(); 1725 } 1726 count = count + humongous_dictionary()->total_free_blocks(); 1727 return count; 1728 } 1729 1730 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) { 1731 ChunkIndex index = list_index(word_size); 1732 assert(index < HumongousIndex, "No humongous list"); 1733 return free_chunks(index); 1734 } 1735 1736 Metachunk* ChunkManager::free_chunks_get(size_t word_size) { 1737 assert_lock_strong(SpaceManager::expand_lock()); 1738 1739 slow_locked_verify(); 1740 1741 Metachunk* chunk = NULL; 1742 if (list_index(word_size) != HumongousIndex) { 1743 ChunkList* free_list = find_free_chunks_list(word_size); 1744 assert(free_list != NULL, "Sanity check"); 1745 1746 chunk = free_list->head(); 1747 1748 if (chunk == NULL) { 1749 return NULL; 1750 } 1751 1752 // Remove the chunk as the head of the list. 1753 free_list->remove_chunk(chunk); 1754 1755 log_trace(gc, metaspace, freelist)("ChunkManager::free_chunks_get: free_list " PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT, 1756 p2i(free_list), p2i(chunk), chunk->word_size()); 1757 } else { 1758 chunk = humongous_dictionary()->get_chunk( 1759 word_size, 1760 FreeBlockDictionary<Metachunk>::atLeast); 1761 1762 if (chunk == NULL) { 1763 return NULL; 1764 } 1765 1766 log_debug(gc, metaspace, alloc)("Free list allocate humongous chunk size " SIZE_FORMAT " for requested size " SIZE_FORMAT " waste " SIZE_FORMAT, 1767 chunk->word_size(), word_size, chunk->word_size() - word_size); 1768 } 1769 1770 // Chunk is being removed from the chunks free list. 1771 dec_free_chunks_total(chunk->word_size()); 1772 1773 // Remove it from the links to this freelist 1774 chunk->set_next(NULL); 1775 chunk->set_prev(NULL); 1776 #ifdef ASSERT 1777 // Chunk is no longer on any freelist. Setting to false make container_count_slow() 1778 // work. 1779 chunk->set_is_tagged_free(false); 1780 #endif 1781 chunk->container()->inc_container_count(); 1782 1783 slow_locked_verify(); 1784 return chunk; 1785 } 1786 1787 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) { 1788 assert_lock_strong(SpaceManager::expand_lock()); 1789 slow_locked_verify(); 1790 1791 // Take from the beginning of the list 1792 Metachunk* chunk = free_chunks_get(word_size); 1793 if (chunk == NULL) { 1794 return NULL; 1795 } 1796 1797 assert((word_size <= chunk->word_size()) || 1798 list_index(chunk->word_size() == HumongousIndex), 1799 "Non-humongous variable sized chunk"); 1800 LogHandle(gc, metaspace, freelist) log; 1801 if (log.is_debug()) { 1802 size_t list_count; 1803 if (list_index(word_size) < HumongousIndex) { 1804 ChunkList* list = find_free_chunks_list(word_size); 1805 list_count = list->count(); 1806 } else { 1807 list_count = humongous_dictionary()->total_count(); 1808 } 1809 log.debug("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk " PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ", 1810 p2i(this), p2i(chunk), chunk->word_size(), list_count); 1811 ResourceMark rm; 1812 locked_print_free_chunks(log.debug_stream()); 1813 } 1814 1815 return chunk; 1816 } 1817 1818 void ChunkManager::print_on(outputStream* out) const { 1819 const_cast<ChunkManager *>(this)->humongous_dictionary()->report_statistics(out); 1820 } 1821 1822 // SpaceManager methods 1823 1824 void SpaceManager::get_initial_chunk_sizes(Metaspace::MetaspaceType type, 1825 size_t* chunk_word_size, 1826 size_t* class_chunk_word_size) { 1827 switch (type) { 1828 case Metaspace::BootMetaspaceType: 1829 *chunk_word_size = Metaspace::first_chunk_word_size(); 1830 *class_chunk_word_size = Metaspace::first_class_chunk_word_size(); 1831 break; 1832 case Metaspace::ROMetaspaceType: 1833 *chunk_word_size = SharedReadOnlySize / wordSize; 1834 *class_chunk_word_size = ClassSpecializedChunk; 1835 break; 1836 case Metaspace::ReadWriteMetaspaceType: 1837 *chunk_word_size = SharedReadWriteSize / wordSize; 1838 *class_chunk_word_size = ClassSpecializedChunk; 1839 break; 1840 case Metaspace::AnonymousMetaspaceType: 1841 case Metaspace::ReflectionMetaspaceType: 1842 *chunk_word_size = SpecializedChunk; 1843 *class_chunk_word_size = ClassSpecializedChunk; 1844 break; 1845 default: 1846 *chunk_word_size = SmallChunk; 1847 *class_chunk_word_size = ClassSmallChunk; 1848 break; 1849 } 1850 assert(*chunk_word_size != 0 && *class_chunk_word_size != 0, 1851 "Initial chunks sizes bad: data " SIZE_FORMAT 1852 " class " SIZE_FORMAT, 1853 *chunk_word_size, *class_chunk_word_size); 1854 } 1855 1856 size_t SpaceManager::sum_free_in_chunks_in_use() const { 1857 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 1858 size_t free = 0; 1859 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 1860 Metachunk* chunk = chunks_in_use(i); 1861 while (chunk != NULL) { 1862 free += chunk->free_word_size(); 1863 chunk = chunk->next(); 1864 } 1865 } 1866 return free; 1867 } 1868 1869 size_t SpaceManager::sum_waste_in_chunks_in_use() const { 1870 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 1871 size_t result = 0; 1872 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 1873 result += sum_waste_in_chunks_in_use(i); 1874 } 1875 1876 return result; 1877 } 1878 1879 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const { 1880 size_t result = 0; 1881 Metachunk* chunk = chunks_in_use(index); 1882 // Count the free space in all the chunk but not the 1883 // current chunk from which allocations are still being done. 1884 while (chunk != NULL) { 1885 if (chunk != current_chunk()) { 1886 result += chunk->free_word_size(); 1887 } 1888 chunk = chunk->next(); 1889 } 1890 return result; 1891 } 1892 1893 size_t SpaceManager::sum_capacity_in_chunks_in_use() const { 1894 // For CMS use "allocated_chunks_words()" which does not need the 1895 // Metaspace lock. For the other collectors sum over the 1896 // lists. Use both methods as a check that "allocated_chunks_words()" 1897 // is correct. That is, sum_capacity_in_chunks() is too expensive 1898 // to use in the product and allocated_chunks_words() should be used 1899 // but allow for checking that allocated_chunks_words() returns the same 1900 // value as sum_capacity_in_chunks_in_use() which is the definitive 1901 // answer. 1902 if (UseConcMarkSweepGC) { 1903 return allocated_chunks_words(); 1904 } else { 1905 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 1906 size_t sum = 0; 1907 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 1908 Metachunk* chunk = chunks_in_use(i); 1909 while (chunk != NULL) { 1910 sum += chunk->word_size(); 1911 chunk = chunk->next(); 1912 } 1913 } 1914 return sum; 1915 } 1916 } 1917 1918 size_t SpaceManager::sum_count_in_chunks_in_use() { 1919 size_t count = 0; 1920 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 1921 count = count + sum_count_in_chunks_in_use(i); 1922 } 1923 1924 return count; 1925 } 1926 1927 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) { 1928 size_t count = 0; 1929 Metachunk* chunk = chunks_in_use(i); 1930 while (chunk != NULL) { 1931 count++; 1932 chunk = chunk->next(); 1933 } 1934 return count; 1935 } 1936 1937 1938 size_t SpaceManager::sum_used_in_chunks_in_use() const { 1939 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 1940 size_t used = 0; 1941 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 1942 Metachunk* chunk = chunks_in_use(i); 1943 while (chunk != NULL) { 1944 used += chunk->used_word_size(); 1945 chunk = chunk->next(); 1946 } 1947 } 1948 return used; 1949 } 1950 1951 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const { 1952 1953 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 1954 Metachunk* chunk = chunks_in_use(i); 1955 st->print("SpaceManager: %s " PTR_FORMAT, 1956 chunk_size_name(i), p2i(chunk)); 1957 if (chunk != NULL) { 1958 st->print_cr(" free " SIZE_FORMAT, 1959 chunk->free_word_size()); 1960 } else { 1961 st->cr(); 1962 } 1963 } 1964 1965 chunk_manager()->locked_print_free_chunks(st); 1966 chunk_manager()->locked_print_sum_free_chunks(st); 1967 } 1968 1969 size_t SpaceManager::calc_chunk_size(size_t word_size) { 1970 1971 // Decide between a small chunk and a medium chunk. Up to 1972 // _small_chunk_limit small chunks can be allocated. 1973 // After that a medium chunk is preferred. 1974 size_t chunk_word_size; 1975 if (chunks_in_use(MediumIndex) == NULL && 1976 sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit) { 1977 chunk_word_size = (size_t) small_chunk_size(); 1978 if (word_size + Metachunk::overhead() > small_chunk_size()) { 1979 chunk_word_size = medium_chunk_size(); 1980 } 1981 } else { 1982 chunk_word_size = medium_chunk_size(); 1983 } 1984 1985 // Might still need a humongous chunk. Enforce 1986 // humongous allocations sizes to be aligned up to 1987 // the smallest chunk size. 1988 size_t if_humongous_sized_chunk = 1989 align_size_up(word_size + Metachunk::overhead(), 1990 smallest_chunk_size()); 1991 chunk_word_size = 1992 MAX2((size_t) chunk_word_size, if_humongous_sized_chunk); 1993 1994 assert(!SpaceManager::is_humongous(word_size) || 1995 chunk_word_size == if_humongous_sized_chunk, 1996 "Size calculation is wrong, word_size " SIZE_FORMAT 1997 " chunk_word_size " SIZE_FORMAT, 1998 word_size, chunk_word_size); 1999 LogHandle(gc, metaspace, alloc) log; 2000 if (log.is_debug() && SpaceManager::is_humongous(word_size)) { 2001 log.debug("Metadata humongous allocation:"); 2002 log.debug(" word_size " PTR_FORMAT, word_size); 2003 log.debug(" chunk_word_size " PTR_FORMAT, chunk_word_size); 2004 log.debug(" chunk overhead " PTR_FORMAT, Metachunk::overhead()); 2005 } 2006 return chunk_word_size; 2007 } 2008 2009 void SpaceManager::track_metaspace_memory_usage() { 2010 if (is_init_completed()) { 2011 if (is_class()) { 2012 MemoryService::track_compressed_class_memory_usage(); 2013 } 2014 MemoryService::track_metaspace_memory_usage(); 2015 } 2016 } 2017 2018 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) { 2019 assert(vs_list()->current_virtual_space() != NULL, 2020 "Should have been set"); 2021 assert(current_chunk() == NULL || 2022 current_chunk()->allocate(word_size) == NULL, 2023 "Don't need to expand"); 2024 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 2025 2026 if (log_is_enabled(Trace, gc, metaspace, freelist)) { 2027 size_t words_left = 0; 2028 size_t words_used = 0; 2029 if (current_chunk() != NULL) { 2030 words_left = current_chunk()->free_word_size(); 2031 words_used = current_chunk()->used_word_size(); 2032 } 2033 log_trace(gc, metaspace, freelist)("SpaceManager::grow_and_allocate for " SIZE_FORMAT " words " SIZE_FORMAT " words used " SIZE_FORMAT " words left", 2034 word_size, words_used, words_left); 2035 } 2036 2037 // Get another chunk 2038 size_t grow_chunks_by_words = calc_chunk_size(word_size); 2039 Metachunk* next = get_new_chunk(word_size, grow_chunks_by_words); 2040 2041 MetaWord* mem = NULL; 2042 2043 // If a chunk was available, add it to the in-use chunk list 2044 // and do an allocation from it. 2045 if (next != NULL) { 2046 // Add to this manager's list of chunks in use. 2047 add_chunk(next, false); 2048 mem = next->allocate(word_size); 2049 } 2050 2051 // Track metaspace memory usage statistic. 2052 track_metaspace_memory_usage(); 2053 2054 return mem; 2055 } 2056 2057 void SpaceManager::print_on(outputStream* st) const { 2058 2059 for (ChunkIndex i = ZeroIndex; 2060 i < NumberOfInUseLists ; 2061 i = next_chunk_index(i) ) { 2062 st->print_cr(" chunks_in_use " PTR_FORMAT " chunk size " SIZE_FORMAT, 2063 p2i(chunks_in_use(i)), 2064 chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size()); 2065 } 2066 st->print_cr(" waste: Small " SIZE_FORMAT " Medium " SIZE_FORMAT 2067 " Humongous " SIZE_FORMAT, 2068 sum_waste_in_chunks_in_use(SmallIndex), 2069 sum_waste_in_chunks_in_use(MediumIndex), 2070 sum_waste_in_chunks_in_use(HumongousIndex)); 2071 // block free lists 2072 if (block_freelists() != NULL) { 2073 st->print_cr("total in block free lists " SIZE_FORMAT, 2074 block_freelists()->total_size()); 2075 } 2076 } 2077 2078 SpaceManager::SpaceManager(Metaspace::MetadataType mdtype, 2079 Mutex* lock) : 2080 _mdtype(mdtype), 2081 _allocated_blocks_words(0), 2082 _allocated_chunks_words(0), 2083 _allocated_chunks_count(0), 2084 _lock(lock) 2085 { 2086 initialize(); 2087 } 2088 2089 void SpaceManager::inc_size_metrics(size_t words) { 2090 assert_lock_strong(SpaceManager::expand_lock()); 2091 // Total of allocated Metachunks and allocated Metachunks count 2092 // for each SpaceManager 2093 _allocated_chunks_words = _allocated_chunks_words + words; 2094 _allocated_chunks_count++; 2095 // Global total of capacity in allocated Metachunks 2096 MetaspaceAux::inc_capacity(mdtype(), words); 2097 // Global total of allocated Metablocks. 2098 // used_words_slow() includes the overhead in each 2099 // Metachunk so include it in the used when the 2100 // Metachunk is first added (so only added once per 2101 // Metachunk). 2102 MetaspaceAux::inc_used(mdtype(), Metachunk::overhead()); 2103 } 2104 2105 void SpaceManager::inc_used_metrics(size_t words) { 2106 // Add to the per SpaceManager total 2107 Atomic::add_ptr(words, &_allocated_blocks_words); 2108 // Add to the global total 2109 MetaspaceAux::inc_used(mdtype(), words); 2110 } 2111 2112 void SpaceManager::dec_total_from_size_metrics() { 2113 MetaspaceAux::dec_capacity(mdtype(), allocated_chunks_words()); 2114 MetaspaceAux::dec_used(mdtype(), allocated_blocks_words()); 2115 // Also deduct the overhead per Metachunk 2116 MetaspaceAux::dec_used(mdtype(), allocated_chunks_count() * Metachunk::overhead()); 2117 } 2118 2119 void SpaceManager::initialize() { 2120 Metadebug::init_allocation_fail_alot_count(); 2121 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2122 _chunks_in_use[i] = NULL; 2123 } 2124 _current_chunk = NULL; 2125 log_trace(gc, metaspace, freelist)("SpaceManager(): " PTR_FORMAT, p2i(this)); 2126 } 2127 2128 void ChunkManager::return_chunks(ChunkIndex index, Metachunk* chunks) { 2129 if (chunks == NULL) { 2130 return; 2131 } 2132 ChunkList* list = free_chunks(index); 2133 assert(list->size() == chunks->word_size(), "Mismatch in chunk sizes"); 2134 assert_lock_strong(SpaceManager::expand_lock()); 2135 Metachunk* cur = chunks; 2136 2137 // This returns chunks one at a time. If a new 2138 // class List can be created that is a base class 2139 // of FreeList then something like FreeList::prepend() 2140 // can be used in place of this loop 2141 while (cur != NULL) { 2142 assert(cur->container() != NULL, "Container should have been set"); 2143 cur->container()->dec_container_count(); 2144 // Capture the next link before it is changed 2145 // by the call to return_chunk_at_head(); 2146 Metachunk* next = cur->next(); 2147 DEBUG_ONLY(cur->set_is_tagged_free(true);) 2148 NOT_PRODUCT(cur->mangle(badMetaWordVal);) 2149 list->return_chunk_at_head(cur); 2150 cur = next; 2151 } 2152 } 2153 2154 SpaceManager::~SpaceManager() { 2155 // This call this->_lock which can't be done while holding expand_lock() 2156 assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(), 2157 "sum_capacity_in_chunks_in_use() " SIZE_FORMAT 2158 " allocated_chunks_words() " SIZE_FORMAT, 2159 sum_capacity_in_chunks_in_use(), allocated_chunks_words()); 2160 2161 MutexLockerEx fcl(SpaceManager::expand_lock(), 2162 Mutex::_no_safepoint_check_flag); 2163 2164 chunk_manager()->slow_locked_verify(); 2165 2166 dec_total_from_size_metrics(); 2167 2168 LogHandle(gc, metaspace, freelist) log; 2169 if (log.is_trace()) { 2170 log.trace("~SpaceManager(): " PTR_FORMAT, p2i(this)); 2171 ResourceMark rm; 2172 locked_print_chunks_in_use_on(log.trace_stream()); 2173 } 2174 2175 // Have to update before the chunks_in_use lists are emptied 2176 // below. 2177 chunk_manager()->inc_free_chunks_total(allocated_chunks_words(), 2178 sum_count_in_chunks_in_use()); 2179 2180 // Add all the chunks in use by this space manager 2181 // to the global list of free chunks. 2182 2183 // Follow each list of chunks-in-use and add them to the 2184 // free lists. Each list is NULL terminated. 2185 2186 for (ChunkIndex i = ZeroIndex; i < HumongousIndex; i = next_chunk_index(i)) { 2187 log.trace("returned " SIZE_FORMAT " %s chunks to freelist", sum_count_in_chunks_in_use(i), chunk_size_name(i)); 2188 Metachunk* chunks = chunks_in_use(i); 2189 chunk_manager()->return_chunks(i, chunks); 2190 set_chunks_in_use(i, NULL); 2191 log.trace("updated freelist count " SSIZE_FORMAT " %s", chunk_manager()->free_chunks(i)->count(), chunk_size_name(i)); 2192 assert(i != HumongousIndex, "Humongous chunks are handled explicitly later"); 2193 } 2194 2195 // The medium chunk case may be optimized by passing the head and 2196 // tail of the medium chunk list to add_at_head(). The tail is often 2197 // the current chunk but there are probably exceptions. 2198 2199 // Humongous chunks 2200 log.trace("returned " SIZE_FORMAT " %s humongous chunks to dictionary", 2201 sum_count_in_chunks_in_use(HumongousIndex), chunk_size_name(HumongousIndex)); 2202 log.trace("Humongous chunk dictionary: "); 2203 // Humongous chunks are never the current chunk. 2204 Metachunk* humongous_chunks = chunks_in_use(HumongousIndex); 2205 2206 while (humongous_chunks != NULL) { 2207 DEBUG_ONLY(humongous_chunks->set_is_tagged_free(true);) 2208 NOT_PRODUCT(humongous_chunks->mangle(badMetaWordVal);) 2209 log.trace(PTR_FORMAT " (" SIZE_FORMAT ") ", p2i(humongous_chunks), humongous_chunks->word_size()); 2210 assert(humongous_chunks->word_size() == (size_t) 2211 align_size_up(humongous_chunks->word_size(), 2212 smallest_chunk_size()), 2213 "Humongous chunk size is wrong: word size " SIZE_FORMAT 2214 " granularity " SIZE_FORMAT, 2215 humongous_chunks->word_size(), smallest_chunk_size()); 2216 Metachunk* next_humongous_chunks = humongous_chunks->next(); 2217 humongous_chunks->container()->dec_container_count(); 2218 chunk_manager()->humongous_dictionary()->return_chunk(humongous_chunks); 2219 humongous_chunks = next_humongous_chunks; 2220 } 2221 log.trace("updated dictionary count " SIZE_FORMAT " %s", chunk_manager()->humongous_dictionary()->total_count(), chunk_size_name(HumongousIndex)); 2222 chunk_manager()->slow_locked_verify(); 2223 } 2224 2225 const char* SpaceManager::chunk_size_name(ChunkIndex index) const { 2226 switch (index) { 2227 case SpecializedIndex: 2228 return "Specialized"; 2229 case SmallIndex: 2230 return "Small"; 2231 case MediumIndex: 2232 return "Medium"; 2233 case HumongousIndex: 2234 return "Humongous"; 2235 default: 2236 return NULL; 2237 } 2238 } 2239 2240 ChunkIndex ChunkManager::list_index(size_t size) { 2241 switch (size) { 2242 case SpecializedChunk: 2243 assert(SpecializedChunk == ClassSpecializedChunk, 2244 "Need branch for ClassSpecializedChunk"); 2245 return SpecializedIndex; 2246 case SmallChunk: 2247 case ClassSmallChunk: 2248 return SmallIndex; 2249 case MediumChunk: 2250 case ClassMediumChunk: 2251 return MediumIndex; 2252 default: 2253 assert(size > MediumChunk || size > ClassMediumChunk, 2254 "Not a humongous chunk"); 2255 return HumongousIndex; 2256 } 2257 } 2258 2259 void SpaceManager::deallocate(MetaWord* p, size_t word_size) { 2260 assert_lock_strong(_lock); 2261 size_t raw_word_size = get_raw_word_size(word_size); 2262 size_t min_size = TreeChunk<Metablock, FreeList<Metablock> >::min_size(); 2263 assert(raw_word_size >= min_size, 2264 "Should not deallocate dark matter " SIZE_FORMAT "<" SIZE_FORMAT, word_size, min_size); 2265 block_freelists()->return_block(p, raw_word_size); 2266 } 2267 2268 // Adds a chunk to the list of chunks in use. 2269 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) { 2270 2271 assert(new_chunk != NULL, "Should not be NULL"); 2272 assert(new_chunk->next() == NULL, "Should not be on a list"); 2273 2274 new_chunk->reset_empty(); 2275 2276 // Find the correct list and and set the current 2277 // chunk for that list. 2278 ChunkIndex index = ChunkManager::list_index(new_chunk->word_size()); 2279 2280 if (index != HumongousIndex) { 2281 retire_current_chunk(); 2282 set_current_chunk(new_chunk); 2283 new_chunk->set_next(chunks_in_use(index)); 2284 set_chunks_in_use(index, new_chunk); 2285 } else { 2286 // For null class loader data and DumpSharedSpaces, the first chunk isn't 2287 // small, so small will be null. Link this first chunk as the current 2288 // chunk. 2289 if (make_current) { 2290 // Set as the current chunk but otherwise treat as a humongous chunk. 2291 set_current_chunk(new_chunk); 2292 } 2293 // Link at head. The _current_chunk only points to a humongous chunk for 2294 // the null class loader metaspace (class and data virtual space managers) 2295 // any humongous chunks so will not point to the tail 2296 // of the humongous chunks list. 2297 new_chunk->set_next(chunks_in_use(HumongousIndex)); 2298 set_chunks_in_use(HumongousIndex, new_chunk); 2299 2300 assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency"); 2301 } 2302 2303 // Add to the running sum of capacity 2304 inc_size_metrics(new_chunk->word_size()); 2305 2306 assert(new_chunk->is_empty(), "Not ready for reuse"); 2307 LogHandle(gc, metaspace, freelist) log; 2308 if (log.is_trace()) { 2309 log.trace("SpaceManager::add_chunk: " SIZE_FORMAT ") ", sum_count_in_chunks_in_use()); 2310 ResourceMark rm; 2311 outputStream* out = log.trace_stream(); 2312 new_chunk->print_on(out); 2313 chunk_manager()->locked_print_free_chunks(out); 2314 } 2315 } 2316 2317 void SpaceManager::retire_current_chunk() { 2318 if (current_chunk() != NULL) { 2319 size_t remaining_words = current_chunk()->free_word_size(); 2320 if (remaining_words >= TreeChunk<Metablock, FreeList<Metablock> >::min_size()) { 2321 block_freelists()->return_block(current_chunk()->allocate(remaining_words), remaining_words); 2322 inc_used_metrics(remaining_words); 2323 } 2324 } 2325 } 2326 2327 Metachunk* SpaceManager::get_new_chunk(size_t word_size, 2328 size_t grow_chunks_by_words) { 2329 // Get a chunk from the chunk freelist 2330 Metachunk* next = chunk_manager()->chunk_freelist_allocate(grow_chunks_by_words); 2331 2332 if (next == NULL) { 2333 next = vs_list()->get_new_chunk(word_size, 2334 grow_chunks_by_words, 2335 medium_chunk_bunch()); 2336 } 2337 2338 LogHandle(gc, metaspace, alloc) log; 2339 if (log.is_debug() && next != NULL && 2340 SpaceManager::is_humongous(next->word_size())) { 2341 log.debug(" new humongous chunk word size " PTR_FORMAT, next->word_size()); 2342 } 2343 2344 return next; 2345 } 2346 2347 /* 2348 * The policy is to allocate up to _small_chunk_limit small chunks 2349 * after which only medium chunks are allocated. This is done to 2350 * reduce fragmentation. In some cases, this can result in a lot 2351 * of small chunks being allocated to the point where it's not 2352 * possible to expand. If this happens, there may be no medium chunks 2353 * available and OOME would be thrown. Instead of doing that, 2354 * if the allocation request size fits in a small chunk, an attempt 2355 * will be made to allocate a small chunk. 2356 */ 2357 MetaWord* SpaceManager::get_small_chunk_and_allocate(size_t word_size) { 2358 size_t raw_word_size = get_raw_word_size(word_size); 2359 2360 if (raw_word_size + Metachunk::overhead() > small_chunk_size()) { 2361 return NULL; 2362 } 2363 2364 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2365 MutexLockerEx cl1(expand_lock(), Mutex::_no_safepoint_check_flag); 2366 2367 Metachunk* chunk = chunk_manager()->chunk_freelist_allocate(small_chunk_size()); 2368 2369 MetaWord* mem = NULL; 2370 2371 if (chunk != NULL) { 2372 // Add chunk to the in-use chunk list and do an allocation from it. 2373 // Add to this manager's list of chunks in use. 2374 add_chunk(chunk, false); 2375 mem = chunk->allocate(raw_word_size); 2376 2377 inc_used_metrics(raw_word_size); 2378 2379 // Track metaspace memory usage statistic. 2380 track_metaspace_memory_usage(); 2381 } 2382 2383 return mem; 2384 } 2385 2386 MetaWord* SpaceManager::allocate(size_t word_size) { 2387 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 2388 2389 size_t raw_word_size = get_raw_word_size(word_size); 2390 BlockFreelist* fl = block_freelists(); 2391 MetaWord* p = NULL; 2392 // Allocation from the dictionary is expensive in the sense that 2393 // the dictionary has to be searched for a size. Don't allocate 2394 // from the dictionary until it starts to get fat. Is this 2395 // a reasonable policy? Maybe an skinny dictionary is fast enough 2396 // for allocations. Do some profiling. JJJ 2397 if (fl->total_size() > allocation_from_dictionary_limit) { 2398 p = fl->get_block(raw_word_size); 2399 } 2400 if (p == NULL) { 2401 p = allocate_work(raw_word_size); 2402 } 2403 2404 return p; 2405 } 2406 2407 // Returns the address of spaced allocated for "word_size". 2408 // This methods does not know about blocks (Metablocks) 2409 MetaWord* SpaceManager::allocate_work(size_t word_size) { 2410 assert_lock_strong(_lock); 2411 #ifdef ASSERT 2412 if (Metadebug::test_metadata_failure()) { 2413 return NULL; 2414 } 2415 #endif 2416 // Is there space in the current chunk? 2417 MetaWord* result = NULL; 2418 2419 // For DumpSharedSpaces, only allocate out of the current chunk which is 2420 // never null because we gave it the size we wanted. Caller reports out 2421 // of memory if this returns null. 2422 if (DumpSharedSpaces) { 2423 assert(current_chunk() != NULL, "should never happen"); 2424 inc_used_metrics(word_size); 2425 return current_chunk()->allocate(word_size); // caller handles null result 2426 } 2427 2428 if (current_chunk() != NULL) { 2429 result = current_chunk()->allocate(word_size); 2430 } 2431 2432 if (result == NULL) { 2433 result = grow_and_allocate(word_size); 2434 } 2435 2436 if (result != NULL) { 2437 inc_used_metrics(word_size); 2438 assert(result != (MetaWord*) chunks_in_use(MediumIndex), 2439 "Head of the list is being allocated"); 2440 } 2441 2442 return result; 2443 } 2444 2445 void SpaceManager::verify() { 2446 // If there are blocks in the dictionary, then 2447 // verification of chunks does not work since 2448 // being in the dictionary alters a chunk. 2449 if (block_freelists()->total_size() == 0) { 2450 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 2451 Metachunk* curr = chunks_in_use(i); 2452 while (curr != NULL) { 2453 curr->verify(); 2454 verify_chunk_size(curr); 2455 curr = curr->next(); 2456 } 2457 } 2458 } 2459 } 2460 2461 void SpaceManager::verify_chunk_size(Metachunk* chunk) { 2462 assert(is_humongous(chunk->word_size()) || 2463 chunk->word_size() == medium_chunk_size() || 2464 chunk->word_size() == small_chunk_size() || 2465 chunk->word_size() == specialized_chunk_size(), 2466 "Chunk size is wrong"); 2467 return; 2468 } 2469 2470 #ifdef ASSERT 2471 void SpaceManager::verify_allocated_blocks_words() { 2472 // Verification is only guaranteed at a safepoint. 2473 assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(), 2474 "Verification can fail if the applications is running"); 2475 assert(allocated_blocks_words() == sum_used_in_chunks_in_use(), 2476 "allocation total is not consistent " SIZE_FORMAT 2477 " vs " SIZE_FORMAT, 2478 allocated_blocks_words(), sum_used_in_chunks_in_use()); 2479 } 2480 2481 #endif 2482 2483 void SpaceManager::dump(outputStream* const out) const { 2484 size_t curr_total = 0; 2485 size_t waste = 0; 2486 uint i = 0; 2487 size_t used = 0; 2488 size_t capacity = 0; 2489 2490 // Add up statistics for all chunks in this SpaceManager. 2491 for (ChunkIndex index = ZeroIndex; 2492 index < NumberOfInUseLists; 2493 index = next_chunk_index(index)) { 2494 for (Metachunk* curr = chunks_in_use(index); 2495 curr != NULL; 2496 curr = curr->next()) { 2497 out->print("%d) ", i++); 2498 curr->print_on(out); 2499 curr_total += curr->word_size(); 2500 used += curr->used_word_size(); 2501 capacity += curr->word_size(); 2502 waste += curr->free_word_size() + curr->overhead();; 2503 } 2504 } 2505 2506 if (log_is_enabled(Trace, gc, metaspace, freelist)) { 2507 block_freelists()->print_on(out); 2508 } 2509 2510 size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size(); 2511 // Free space isn't wasted. 2512 waste -= free; 2513 2514 out->print_cr("total of all chunks " SIZE_FORMAT " used " SIZE_FORMAT 2515 " free " SIZE_FORMAT " capacity " SIZE_FORMAT 2516 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste); 2517 } 2518 2519 #ifndef PRODUCT 2520 void SpaceManager::mangle_freed_chunks() { 2521 for (ChunkIndex index = ZeroIndex; 2522 index < NumberOfInUseLists; 2523 index = next_chunk_index(index)) { 2524 for (Metachunk* curr = chunks_in_use(index); 2525 curr != NULL; 2526 curr = curr->next()) { 2527 curr->mangle(); 2528 } 2529 } 2530 } 2531 #endif // PRODUCT 2532 2533 // MetaspaceAux 2534 2535 2536 size_t MetaspaceAux::_capacity_words[] = {0, 0}; 2537 size_t MetaspaceAux::_used_words[] = {0, 0}; 2538 2539 size_t MetaspaceAux::free_bytes(Metaspace::MetadataType mdtype) { 2540 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2541 return list == NULL ? 0 : list->free_bytes(); 2542 } 2543 2544 size_t MetaspaceAux::free_bytes() { 2545 return free_bytes(Metaspace::ClassType) + free_bytes(Metaspace::NonClassType); 2546 } 2547 2548 void MetaspaceAux::dec_capacity(Metaspace::MetadataType mdtype, size_t words) { 2549 assert_lock_strong(SpaceManager::expand_lock()); 2550 assert(words <= capacity_words(mdtype), 2551 "About to decrement below 0: words " SIZE_FORMAT 2552 " is greater than _capacity_words[%u] " SIZE_FORMAT, 2553 words, mdtype, capacity_words(mdtype)); 2554 _capacity_words[mdtype] -= words; 2555 } 2556 2557 void MetaspaceAux::inc_capacity(Metaspace::MetadataType mdtype, size_t words) { 2558 assert_lock_strong(SpaceManager::expand_lock()); 2559 // Needs to be atomic 2560 _capacity_words[mdtype] += words; 2561 } 2562 2563 void MetaspaceAux::dec_used(Metaspace::MetadataType mdtype, size_t words) { 2564 assert(words <= used_words(mdtype), 2565 "About to decrement below 0: words " SIZE_FORMAT 2566 " is greater than _used_words[%u] " SIZE_FORMAT, 2567 words, mdtype, used_words(mdtype)); 2568 // For CMS deallocation of the Metaspaces occurs during the 2569 // sweep which is a concurrent phase. Protection by the expand_lock() 2570 // is not enough since allocation is on a per Metaspace basis 2571 // and protected by the Metaspace lock. 2572 jlong minus_words = (jlong) - (jlong) words; 2573 Atomic::add_ptr(minus_words, &_used_words[mdtype]); 2574 } 2575 2576 void MetaspaceAux::inc_used(Metaspace::MetadataType mdtype, size_t words) { 2577 // _used_words tracks allocations for 2578 // each piece of metadata. Those allocations are 2579 // generally done concurrently by different application 2580 // threads so must be done atomically. 2581 Atomic::add_ptr(words, &_used_words[mdtype]); 2582 } 2583 2584 size_t MetaspaceAux::used_bytes_slow(Metaspace::MetadataType mdtype) { 2585 size_t used = 0; 2586 ClassLoaderDataGraphMetaspaceIterator iter; 2587 while (iter.repeat()) { 2588 Metaspace* msp = iter.get_next(); 2589 // Sum allocated_blocks_words for each metaspace 2590 if (msp != NULL) { 2591 used += msp->used_words_slow(mdtype); 2592 } 2593 } 2594 return used * BytesPerWord; 2595 } 2596 2597 size_t MetaspaceAux::free_bytes_slow(Metaspace::MetadataType mdtype) { 2598 size_t free = 0; 2599 ClassLoaderDataGraphMetaspaceIterator iter; 2600 while (iter.repeat()) { 2601 Metaspace* msp = iter.get_next(); 2602 if (msp != NULL) { 2603 free += msp->free_words_slow(mdtype); 2604 } 2605 } 2606 return free * BytesPerWord; 2607 } 2608 2609 size_t MetaspaceAux::capacity_bytes_slow(Metaspace::MetadataType mdtype) { 2610 if ((mdtype == Metaspace::ClassType) && !Metaspace::using_class_space()) { 2611 return 0; 2612 } 2613 // Don't count the space in the freelists. That space will be 2614 // added to the capacity calculation as needed. 2615 size_t capacity = 0; 2616 ClassLoaderDataGraphMetaspaceIterator iter; 2617 while (iter.repeat()) { 2618 Metaspace* msp = iter.get_next(); 2619 if (msp != NULL) { 2620 capacity += msp->capacity_words_slow(mdtype); 2621 } 2622 } 2623 return capacity * BytesPerWord; 2624 } 2625 2626 size_t MetaspaceAux::capacity_bytes_slow() { 2627 #ifdef PRODUCT 2628 // Use capacity_bytes() in PRODUCT instead of this function. 2629 guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT"); 2630 #endif 2631 size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType); 2632 size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType); 2633 assert(capacity_bytes() == class_capacity + non_class_capacity, 2634 "bad accounting: capacity_bytes() " SIZE_FORMAT 2635 " class_capacity + non_class_capacity " SIZE_FORMAT 2636 " class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT, 2637 capacity_bytes(), class_capacity + non_class_capacity, 2638 class_capacity, non_class_capacity); 2639 2640 return class_capacity + non_class_capacity; 2641 } 2642 2643 size_t MetaspaceAux::reserved_bytes(Metaspace::MetadataType mdtype) { 2644 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2645 return list == NULL ? 0 : list->reserved_bytes(); 2646 } 2647 2648 size_t MetaspaceAux::committed_bytes(Metaspace::MetadataType mdtype) { 2649 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 2650 return list == NULL ? 0 : list->committed_bytes(); 2651 } 2652 2653 size_t MetaspaceAux::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); } 2654 2655 size_t MetaspaceAux::free_chunks_total_words(Metaspace::MetadataType mdtype) { 2656 ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype); 2657 if (chunk_manager == NULL) { 2658 return 0; 2659 } 2660 chunk_manager->slow_verify(); 2661 return chunk_manager->free_chunks_total_words(); 2662 } 2663 2664 size_t MetaspaceAux::free_chunks_total_bytes(Metaspace::MetadataType mdtype) { 2665 return free_chunks_total_words(mdtype) * BytesPerWord; 2666 } 2667 2668 size_t MetaspaceAux::free_chunks_total_words() { 2669 return free_chunks_total_words(Metaspace::ClassType) + 2670 free_chunks_total_words(Metaspace::NonClassType); 2671 } 2672 2673 size_t MetaspaceAux::free_chunks_total_bytes() { 2674 return free_chunks_total_words() * BytesPerWord; 2675 } 2676 2677 bool MetaspaceAux::has_chunk_free_list(Metaspace::MetadataType mdtype) { 2678 return Metaspace::get_chunk_manager(mdtype) != NULL; 2679 } 2680 2681 MetaspaceChunkFreeListSummary MetaspaceAux::chunk_free_list_summary(Metaspace::MetadataType mdtype) { 2682 if (!has_chunk_free_list(mdtype)) { 2683 return MetaspaceChunkFreeListSummary(); 2684 } 2685 2686 const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype); 2687 return cm->chunk_free_list_summary(); 2688 } 2689 2690 void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) { 2691 log_info(gc, metaspace)("Metaspace: " SIZE_FORMAT "K->" SIZE_FORMAT "K(" SIZE_FORMAT "K)", 2692 prev_metadata_used/K, used_bytes()/K, reserved_bytes()/K); 2693 } 2694 2695 void MetaspaceAux::print_on(outputStream* out) { 2696 Metaspace::MetadataType nct = Metaspace::NonClassType; 2697 2698 out->print_cr(" Metaspace " 2699 "used " SIZE_FORMAT "K, " 2700 "capacity " SIZE_FORMAT "K, " 2701 "committed " SIZE_FORMAT "K, " 2702 "reserved " SIZE_FORMAT "K", 2703 used_bytes()/K, 2704 capacity_bytes()/K, 2705 committed_bytes()/K, 2706 reserved_bytes()/K); 2707 2708 if (Metaspace::using_class_space()) { 2709 Metaspace::MetadataType ct = Metaspace::ClassType; 2710 out->print_cr(" class space " 2711 "used " SIZE_FORMAT "K, " 2712 "capacity " SIZE_FORMAT "K, " 2713 "committed " SIZE_FORMAT "K, " 2714 "reserved " SIZE_FORMAT "K", 2715 used_bytes(ct)/K, 2716 capacity_bytes(ct)/K, 2717 committed_bytes(ct)/K, 2718 reserved_bytes(ct)/K); 2719 } 2720 } 2721 2722 // Print information for class space and data space separately. 2723 // This is almost the same as above. 2724 void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) { 2725 size_t free_chunks_capacity_bytes = free_chunks_total_bytes(mdtype); 2726 size_t capacity_bytes = capacity_bytes_slow(mdtype); 2727 size_t used_bytes = used_bytes_slow(mdtype); 2728 size_t free_bytes = free_bytes_slow(mdtype); 2729 size_t used_and_free = used_bytes + free_bytes + 2730 free_chunks_capacity_bytes; 2731 out->print_cr(" Chunk accounting: used in chunks " SIZE_FORMAT 2732 "K + unused in chunks " SIZE_FORMAT "K + " 2733 " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT 2734 "K capacity in allocated chunks " SIZE_FORMAT "K", 2735 used_bytes / K, 2736 free_bytes / K, 2737 free_chunks_capacity_bytes / K, 2738 used_and_free / K, 2739 capacity_bytes / K); 2740 // Accounting can only be correct if we got the values during a safepoint 2741 assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong"); 2742 } 2743 2744 // Print total fragmentation for class metaspaces 2745 void MetaspaceAux::print_class_waste(outputStream* out) { 2746 assert(Metaspace::using_class_space(), "class metaspace not used"); 2747 size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0; 2748 size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_humongous_count = 0; 2749 ClassLoaderDataGraphMetaspaceIterator iter; 2750 while (iter.repeat()) { 2751 Metaspace* msp = iter.get_next(); 2752 if (msp != NULL) { 2753 cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex); 2754 cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex); 2755 cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex); 2756 cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex); 2757 cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex); 2758 cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex); 2759 cls_humongous_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex); 2760 } 2761 } 2762 out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", " 2763 SIZE_FORMAT " small(s) " SIZE_FORMAT ", " 2764 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", " 2765 "large count " SIZE_FORMAT, 2766 cls_specialized_count, cls_specialized_waste, 2767 cls_small_count, cls_small_waste, 2768 cls_medium_count, cls_medium_waste, cls_humongous_count); 2769 } 2770 2771 // Print total fragmentation for data and class metaspaces separately 2772 void MetaspaceAux::print_waste(outputStream* out) { 2773 size_t specialized_waste = 0, small_waste = 0, medium_waste = 0; 2774 size_t specialized_count = 0, small_count = 0, medium_count = 0, humongous_count = 0; 2775 2776 ClassLoaderDataGraphMetaspaceIterator iter; 2777 while (iter.repeat()) { 2778 Metaspace* msp = iter.get_next(); 2779 if (msp != NULL) { 2780 specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex); 2781 specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex); 2782 small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex); 2783 small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex); 2784 medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex); 2785 medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex); 2786 humongous_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex); 2787 } 2788 } 2789 out->print_cr("Total fragmentation waste (words) doesn't count free space"); 2790 out->print_cr(" data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", " 2791 SIZE_FORMAT " small(s) " SIZE_FORMAT ", " 2792 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", " 2793 "large count " SIZE_FORMAT, 2794 specialized_count, specialized_waste, small_count, 2795 small_waste, medium_count, medium_waste, humongous_count); 2796 if (Metaspace::using_class_space()) { 2797 print_class_waste(out); 2798 } 2799 } 2800 2801 // Dump global metaspace things from the end of ClassLoaderDataGraph 2802 void MetaspaceAux::dump(outputStream* out) { 2803 out->print_cr("All Metaspace:"); 2804 out->print("data space: "); print_on(out, Metaspace::NonClassType); 2805 out->print("class space: "); print_on(out, Metaspace::ClassType); 2806 print_waste(out); 2807 } 2808 2809 void MetaspaceAux::verify_free_chunks() { 2810 Metaspace::chunk_manager_metadata()->verify(); 2811 if (Metaspace::using_class_space()) { 2812 Metaspace::chunk_manager_class()->verify(); 2813 } 2814 } 2815 2816 void MetaspaceAux::verify_capacity() { 2817 #ifdef ASSERT 2818 size_t running_sum_capacity_bytes = capacity_bytes(); 2819 // For purposes of the running sum of capacity, verify against capacity 2820 size_t capacity_in_use_bytes = capacity_bytes_slow(); 2821 assert(running_sum_capacity_bytes == capacity_in_use_bytes, 2822 "capacity_words() * BytesPerWord " SIZE_FORMAT 2823 " capacity_bytes_slow()" SIZE_FORMAT, 2824 running_sum_capacity_bytes, capacity_in_use_bytes); 2825 for (Metaspace::MetadataType i = Metaspace::ClassType; 2826 i < Metaspace:: MetadataTypeCount; 2827 i = (Metaspace::MetadataType)(i + 1)) { 2828 size_t capacity_in_use_bytes = capacity_bytes_slow(i); 2829 assert(capacity_bytes(i) == capacity_in_use_bytes, 2830 "capacity_bytes(%u) " SIZE_FORMAT 2831 " capacity_bytes_slow(%u)" SIZE_FORMAT, 2832 i, capacity_bytes(i), i, capacity_in_use_bytes); 2833 } 2834 #endif 2835 } 2836 2837 void MetaspaceAux::verify_used() { 2838 #ifdef ASSERT 2839 size_t running_sum_used_bytes = used_bytes(); 2840 // For purposes of the running sum of used, verify against used 2841 size_t used_in_use_bytes = used_bytes_slow(); 2842 assert(used_bytes() == used_in_use_bytes, 2843 "used_bytes() " SIZE_FORMAT 2844 " used_bytes_slow()" SIZE_FORMAT, 2845 used_bytes(), used_in_use_bytes); 2846 for (Metaspace::MetadataType i = Metaspace::ClassType; 2847 i < Metaspace:: MetadataTypeCount; 2848 i = (Metaspace::MetadataType)(i + 1)) { 2849 size_t used_in_use_bytes = used_bytes_slow(i); 2850 assert(used_bytes(i) == used_in_use_bytes, 2851 "used_bytes(%u) " SIZE_FORMAT 2852 " used_bytes_slow(%u)" SIZE_FORMAT, 2853 i, used_bytes(i), i, used_in_use_bytes); 2854 } 2855 #endif 2856 } 2857 2858 void MetaspaceAux::verify_metrics() { 2859 verify_capacity(); 2860 verify_used(); 2861 } 2862 2863 2864 // Metaspace methods 2865 2866 size_t Metaspace::_first_chunk_word_size = 0; 2867 size_t Metaspace::_first_class_chunk_word_size = 0; 2868 2869 size_t Metaspace::_commit_alignment = 0; 2870 size_t Metaspace::_reserve_alignment = 0; 2871 2872 Metaspace::Metaspace(Mutex* lock, MetaspaceType type) { 2873 initialize(lock, type); 2874 } 2875 2876 Metaspace::~Metaspace() { 2877 delete _vsm; 2878 if (using_class_space()) { 2879 delete _class_vsm; 2880 } 2881 } 2882 2883 VirtualSpaceList* Metaspace::_space_list = NULL; 2884 VirtualSpaceList* Metaspace::_class_space_list = NULL; 2885 2886 ChunkManager* Metaspace::_chunk_manager_metadata = NULL; 2887 ChunkManager* Metaspace::_chunk_manager_class = NULL; 2888 2889 #define VIRTUALSPACEMULTIPLIER 2 2890 2891 #ifdef _LP64 2892 static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1); 2893 2894 void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) { 2895 // Figure out the narrow_klass_base and the narrow_klass_shift. The 2896 // narrow_klass_base is the lower of the metaspace base and the cds base 2897 // (if cds is enabled). The narrow_klass_shift depends on the distance 2898 // between the lower base and higher address. 2899 address lower_base; 2900 address higher_address; 2901 #if INCLUDE_CDS 2902 if (UseSharedSpaces) { 2903 higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()), 2904 (address)(metaspace_base + compressed_class_space_size())); 2905 lower_base = MIN2(metaspace_base, cds_base); 2906 } else 2907 #endif 2908 { 2909 higher_address = metaspace_base + compressed_class_space_size(); 2910 lower_base = metaspace_base; 2911 2912 uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes; 2913 // If compressed class space fits in lower 32G, we don't need a base. 2914 if (higher_address <= (address)klass_encoding_max) { 2915 lower_base = 0; // Effectively lower base is zero. 2916 } 2917 } 2918 2919 Universe::set_narrow_klass_base(lower_base); 2920 2921 if ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) { 2922 Universe::set_narrow_klass_shift(0); 2923 } else { 2924 assert(!UseSharedSpaces, "Cannot shift with UseSharedSpaces"); 2925 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes); 2926 } 2927 } 2928 2929 #if INCLUDE_CDS 2930 // Return TRUE if the specified metaspace_base and cds_base are close enough 2931 // to work with compressed klass pointers. 2932 bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) { 2933 assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS"); 2934 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); 2935 address lower_base = MIN2((address)metaspace_base, cds_base); 2936 address higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()), 2937 (address)(metaspace_base + compressed_class_space_size())); 2938 return ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax); 2939 } 2940 #endif 2941 2942 // Try to allocate the metaspace at the requested addr. 2943 void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) { 2944 assert(using_class_space(), "called improperly"); 2945 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); 2946 assert(compressed_class_space_size() < KlassEncodingMetaspaceMax, 2947 "Metaspace size is too big"); 2948 assert_is_ptr_aligned(requested_addr, _reserve_alignment); 2949 assert_is_ptr_aligned(cds_base, _reserve_alignment); 2950 assert_is_size_aligned(compressed_class_space_size(), _reserve_alignment); 2951 2952 // Don't use large pages for the class space. 2953 bool large_pages = false; 2954 2955 #ifndef AARCH64 2956 ReservedSpace metaspace_rs = ReservedSpace(compressed_class_space_size(), 2957 _reserve_alignment, 2958 large_pages, 2959 requested_addr); 2960 #else // AARCH64 2961 ReservedSpace metaspace_rs; 2962 2963 // Our compressed klass pointers may fit nicely into the lower 32 2964 // bits. 2965 if ((uint64_t)requested_addr + compressed_class_space_size() < 4*G) { 2966 metaspace_rs = ReservedSpace(compressed_class_space_size(), 2967 _reserve_alignment, 2968 large_pages, 2969 requested_addr); 2970 } 2971 2972 if (! metaspace_rs.is_reserved()) { 2973 // Try to align metaspace so that we can decode a compressed klass 2974 // with a single MOVK instruction. We can do this iff the 2975 // compressed class base is a multiple of 4G. 2976 for (char *a = (char*)align_ptr_up(requested_addr, 4*G); 2977 a < (char*)(1024*G); 2978 a += 4*G) { 2979 2980 #if INCLUDE_CDS 2981 if (UseSharedSpaces 2982 && ! can_use_cds_with_metaspace_addr(a, cds_base)) { 2983 // We failed to find an aligned base that will reach. Fall 2984 // back to using our requested addr. 2985 metaspace_rs = ReservedSpace(compressed_class_space_size(), 2986 _reserve_alignment, 2987 large_pages, 2988 requested_addr); 2989 break; 2990 } 2991 #endif 2992 2993 metaspace_rs = ReservedSpace(compressed_class_space_size(), 2994 _reserve_alignment, 2995 large_pages, 2996 a); 2997 if (metaspace_rs.is_reserved()) 2998 break; 2999 } 3000 } 3001 3002 #endif // AARCH64 3003 3004 if (!metaspace_rs.is_reserved()) { 3005 #if INCLUDE_CDS 3006 if (UseSharedSpaces) { 3007 size_t increment = align_size_up(1*G, _reserve_alignment); 3008 3009 // Keep trying to allocate the metaspace, increasing the requested_addr 3010 // by 1GB each time, until we reach an address that will no longer allow 3011 // use of CDS with compressed klass pointers. 3012 char *addr = requested_addr; 3013 while (!metaspace_rs.is_reserved() && (addr + increment > addr) && 3014 can_use_cds_with_metaspace_addr(addr + increment, cds_base)) { 3015 addr = addr + increment; 3016 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3017 _reserve_alignment, large_pages, addr); 3018 } 3019 } 3020 #endif 3021 // If no successful allocation then try to allocate the space anywhere. If 3022 // that fails then OOM doom. At this point we cannot try allocating the 3023 // metaspace as if UseCompressedClassPointers is off because too much 3024 // initialization has happened that depends on UseCompressedClassPointers. 3025 // So, UseCompressedClassPointers cannot be turned off at this point. 3026 if (!metaspace_rs.is_reserved()) { 3027 metaspace_rs = ReservedSpace(compressed_class_space_size(), 3028 _reserve_alignment, large_pages); 3029 if (!metaspace_rs.is_reserved()) { 3030 vm_exit_during_initialization(err_msg("Could not allocate metaspace: " SIZE_FORMAT " bytes", 3031 compressed_class_space_size())); 3032 } 3033 } 3034 } 3035 3036 // If we got here then the metaspace got allocated. 3037 MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass); 3038 3039 #if INCLUDE_CDS 3040 // Verify that we can use shared spaces. Otherwise, turn off CDS. 3041 if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) { 3042 FileMapInfo::stop_sharing_and_unmap( 3043 "Could not allocate metaspace at a compatible address"); 3044 } 3045 #endif 3046 set_narrow_klass_base_and_shift((address)metaspace_rs.base(), 3047 UseSharedSpaces ? (address)cds_base : 0); 3048 3049 initialize_class_space(metaspace_rs); 3050 3051 if (log_is_enabled(Trace, gc, metaspace)) { 3052 LogHandle(gc, metaspace) log; 3053 ResourceMark rm; 3054 print_compressed_class_space(log.trace_stream(), requested_addr); 3055 } 3056 } 3057 3058 void Metaspace::print_compressed_class_space(outputStream* st, const char* requested_addr) { 3059 st->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: %d", 3060 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift()); 3061 if (_class_space_list != NULL) { 3062 address base = (address)_class_space_list->current_virtual_space()->bottom(); 3063 st->print("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT, 3064 compressed_class_space_size(), p2i(base)); 3065 if (requested_addr != 0) { 3066 st->print(" Req Addr: " PTR_FORMAT, p2i(requested_addr)); 3067 } 3068 st->cr(); 3069 } 3070 } 3071 3072 // For UseCompressedClassPointers the class space is reserved above the top of 3073 // the Java heap. The argument passed in is at the base of the compressed space. 3074 void Metaspace::initialize_class_space(ReservedSpace rs) { 3075 // The reserved space size may be bigger because of alignment, esp with UseLargePages 3076 assert(rs.size() >= CompressedClassSpaceSize, 3077 SIZE_FORMAT " != " SIZE_FORMAT, rs.size(), CompressedClassSpaceSize); 3078 assert(using_class_space(), "Must be using class space"); 3079 _class_space_list = new VirtualSpaceList(rs); 3080 _chunk_manager_class = new ChunkManager(SpecializedChunk, ClassSmallChunk, ClassMediumChunk); 3081 3082 if (!_class_space_list->initialization_succeeded()) { 3083 vm_exit_during_initialization("Failed to setup compressed class space virtual space list."); 3084 } 3085 } 3086 3087 #endif 3088 3089 void Metaspace::ergo_initialize() { 3090 if (DumpSharedSpaces) { 3091 // Using large pages when dumping the shared archive is currently not implemented. 3092 FLAG_SET_ERGO(bool, UseLargePagesInMetaspace, false); 3093 } 3094 3095 size_t page_size = os::vm_page_size(); 3096 if (UseLargePages && UseLargePagesInMetaspace) { 3097 page_size = os::large_page_size(); 3098 } 3099 3100 _commit_alignment = page_size; 3101 _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity()); 3102 3103 // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will 3104 // override if MaxMetaspaceSize was set on the command line or not. 3105 // This information is needed later to conform to the specification of the 3106 // java.lang.management.MemoryUsage API. 3107 // 3108 // Ideally, we would be able to set the default value of MaxMetaspaceSize in 3109 // globals.hpp to the aligned value, but this is not possible, since the 3110 // alignment depends on other flags being parsed. 3111 MaxMetaspaceSize = align_size_down_bounded(MaxMetaspaceSize, _reserve_alignment); 3112 3113 if (MetaspaceSize > MaxMetaspaceSize) { 3114 MetaspaceSize = MaxMetaspaceSize; 3115 } 3116 3117 MetaspaceSize = align_size_down_bounded(MetaspaceSize, _commit_alignment); 3118 3119 assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize"); 3120 3121 if (MetaspaceSize < 256*K) { 3122 vm_exit_during_initialization("Too small initial Metaspace size"); 3123 } 3124 3125 MinMetaspaceExpansion = align_size_down_bounded(MinMetaspaceExpansion, _commit_alignment); 3126 MaxMetaspaceExpansion = align_size_down_bounded(MaxMetaspaceExpansion, _commit_alignment); 3127 3128 CompressedClassSpaceSize = align_size_down_bounded(CompressedClassSpaceSize, _reserve_alignment); 3129 set_compressed_class_space_size(CompressedClassSpaceSize); 3130 } 3131 3132 void Metaspace::global_initialize() { 3133 MetaspaceGC::initialize(); 3134 3135 // Initialize the alignment for shared spaces. 3136 int max_alignment = os::vm_allocation_granularity(); 3137 size_t cds_total = 0; 3138 3139 MetaspaceShared::set_max_alignment(max_alignment); 3140 3141 if (DumpSharedSpaces) { 3142 #if INCLUDE_CDS 3143 MetaspaceShared::estimate_regions_size(); 3144 3145 SharedReadOnlySize = align_size_up(SharedReadOnlySize, max_alignment); 3146 SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment); 3147 SharedMiscDataSize = align_size_up(SharedMiscDataSize, max_alignment); 3148 SharedMiscCodeSize = align_size_up(SharedMiscCodeSize, max_alignment); 3149 3150 // Initialize with the sum of the shared space sizes. The read-only 3151 // and read write metaspace chunks will be allocated out of this and the 3152 // remainder is the misc code and data chunks. 3153 cds_total = FileMapInfo::shared_spaces_size(); 3154 cds_total = align_size_up(cds_total, _reserve_alignment); 3155 _space_list = new VirtualSpaceList(cds_total/wordSize); 3156 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk); 3157 3158 if (!_space_list->initialization_succeeded()) { 3159 vm_exit_during_initialization("Unable to dump shared archive.", NULL); 3160 } 3161 3162 #ifdef _LP64 3163 if (cds_total + compressed_class_space_size() > UnscaledClassSpaceMax) { 3164 vm_exit_during_initialization("Unable to dump shared archive.", 3165 err_msg("Size of archive (" SIZE_FORMAT ") + compressed class space (" 3166 SIZE_FORMAT ") == total (" SIZE_FORMAT ") is larger than compressed " 3167 "klass limit: " UINT64_FORMAT, cds_total, compressed_class_space_size(), 3168 cds_total + compressed_class_space_size(), UnscaledClassSpaceMax)); 3169 } 3170 3171 // Set the compressed klass pointer base so that decoding of these pointers works 3172 // properly when creating the shared archive. 3173 assert(UseCompressedOops && UseCompressedClassPointers, 3174 "UseCompressedOops and UseCompressedClassPointers must be set"); 3175 Universe::set_narrow_klass_base((address)_space_list->current_virtual_space()->bottom()); 3176 log_develop_trace(gc, metaspace)("Setting_narrow_klass_base to Address: " PTR_FORMAT, 3177 p2i(_space_list->current_virtual_space()->bottom())); 3178 3179 Universe::set_narrow_klass_shift(0); 3180 #endif // _LP64 3181 #endif // INCLUDE_CDS 3182 } else { 3183 // If using shared space, open the file that contains the shared space 3184 // and map in the memory before initializing the rest of metaspace (so 3185 // the addresses don't conflict) 3186 address cds_address = NULL; 3187 if (UseSharedSpaces) { 3188 #if INCLUDE_CDS 3189 FileMapInfo* mapinfo = new FileMapInfo(); 3190 3191 // Open the shared archive file, read and validate the header. If 3192 // initialization fails, shared spaces [UseSharedSpaces] are 3193 // disabled and the file is closed. 3194 // Map in spaces now also 3195 if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) { 3196 cds_total = FileMapInfo::shared_spaces_size(); 3197 cds_address = (address)mapinfo->header()->region_addr(0); 3198 #ifdef _LP64 3199 if (using_class_space()) { 3200 char* cds_end = (char*)(cds_address + cds_total); 3201 cds_end = (char *)align_ptr_up(cds_end, _reserve_alignment); 3202 // If UseCompressedClassPointers is set then allocate the metaspace area 3203 // above the heap and above the CDS area (if it exists). 3204 allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address); 3205 // Map the shared string space after compressed pointers 3206 // because it relies on compressed class pointers setting to work 3207 mapinfo->map_string_regions(); 3208 } 3209 #endif // _LP64 3210 } else { 3211 assert(!mapinfo->is_open() && !UseSharedSpaces, 3212 "archive file not closed or shared spaces not disabled."); 3213 } 3214 #endif // INCLUDE_CDS 3215 } 3216 3217 #ifdef _LP64 3218 if (!UseSharedSpaces && using_class_space()) { 3219 char* base = (char*)align_ptr_up(Universe::heap()->reserved_region().end(), _reserve_alignment); 3220 allocate_metaspace_compressed_klass_ptrs(base, 0); 3221 } 3222 #endif // _LP64 3223 3224 // Initialize these before initializing the VirtualSpaceList 3225 _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord; 3226 _first_chunk_word_size = align_word_size_up(_first_chunk_word_size); 3227 // Make the first class chunk bigger than a medium chunk so it's not put 3228 // on the medium chunk list. The next chunk will be small and progress 3229 // from there. This size calculated by -version. 3230 _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6, 3231 (CompressedClassSpaceSize/BytesPerWord)*2); 3232 _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size); 3233 // Arbitrarily set the initial virtual space to a multiple 3234 // of the boot class loader size. 3235 size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size; 3236 word_size = align_size_up(word_size, Metaspace::reserve_alignment_words()); 3237 3238 // Initialize the list of virtual spaces. 3239 _space_list = new VirtualSpaceList(word_size); 3240 _chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk); 3241 3242 if (!_space_list->initialization_succeeded()) { 3243 vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL); 3244 } 3245 } 3246 3247 _tracer = new MetaspaceTracer(); 3248 } 3249 3250 void Metaspace::post_initialize() { 3251 MetaspaceGC::post_initialize(); 3252 } 3253 3254 Metachunk* Metaspace::get_initialization_chunk(MetadataType mdtype, 3255 size_t chunk_word_size, 3256 size_t chunk_bunch) { 3257 // Get a chunk from the chunk freelist 3258 Metachunk* chunk = get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size); 3259 if (chunk != NULL) { 3260 return chunk; 3261 } 3262 3263 return get_space_list(mdtype)->get_new_chunk(chunk_word_size, chunk_word_size, chunk_bunch); 3264 } 3265 3266 void Metaspace::initialize(Mutex* lock, MetaspaceType type) { 3267 3268 assert(space_list() != NULL, 3269 "Metadata VirtualSpaceList has not been initialized"); 3270 assert(chunk_manager_metadata() != NULL, 3271 "Metadata ChunkManager has not been initialized"); 3272 3273 _vsm = new SpaceManager(NonClassType, lock); 3274 if (_vsm == NULL) { 3275 return; 3276 } 3277 size_t word_size; 3278 size_t class_word_size; 3279 vsm()->get_initial_chunk_sizes(type, &word_size, &class_word_size); 3280 3281 if (using_class_space()) { 3282 assert(class_space_list() != NULL, 3283 "Class VirtualSpaceList has not been initialized"); 3284 assert(chunk_manager_class() != NULL, 3285 "Class ChunkManager has not been initialized"); 3286 3287 // Allocate SpaceManager for classes. 3288 _class_vsm = new SpaceManager(ClassType, lock); 3289 if (_class_vsm == NULL) { 3290 return; 3291 } 3292 } 3293 3294 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3295 3296 // Allocate chunk for metadata objects 3297 Metachunk* new_chunk = get_initialization_chunk(NonClassType, 3298 word_size, 3299 vsm()->medium_chunk_bunch()); 3300 // For dumping shared archive, report error if allocation has failed. 3301 if (DumpSharedSpaces && new_chunk == NULL) { 3302 report_insufficient_metaspace(MetaspaceAux::committed_bytes() + word_size * BytesPerWord); 3303 } 3304 assert(!DumpSharedSpaces || new_chunk != NULL, "should have enough space for both chunks"); 3305 if (new_chunk != NULL) { 3306 // Add to this manager's list of chunks in use and current_chunk(). 3307 vsm()->add_chunk(new_chunk, true); 3308 } 3309 3310 // Allocate chunk for class metadata objects 3311 if (using_class_space()) { 3312 Metachunk* class_chunk = get_initialization_chunk(ClassType, 3313 class_word_size, 3314 class_vsm()->medium_chunk_bunch()); 3315 if (class_chunk != NULL) { 3316 class_vsm()->add_chunk(class_chunk, true); 3317 } else { 3318 // For dumping shared archive, report error if allocation has failed. 3319 if (DumpSharedSpaces) { 3320 report_insufficient_metaspace(MetaspaceAux::committed_bytes() + class_word_size * BytesPerWord); 3321 } 3322 } 3323 } 3324 3325 _alloc_record_head = NULL; 3326 _alloc_record_tail = NULL; 3327 } 3328 3329 size_t Metaspace::align_word_size_up(size_t word_size) { 3330 size_t byte_size = word_size * wordSize; 3331 return ReservedSpace::allocation_align_size_up(byte_size) / wordSize; 3332 } 3333 3334 MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) { 3335 // DumpSharedSpaces doesn't use class metadata area (yet) 3336 // Also, don't use class_vsm() unless UseCompressedClassPointers is true. 3337 if (is_class_space_allocation(mdtype)) { 3338 return class_vsm()->allocate(word_size); 3339 } else { 3340 return vsm()->allocate(word_size); 3341 } 3342 } 3343 3344 MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) { 3345 size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord); 3346 assert(delta_bytes > 0, "Must be"); 3347 3348 size_t before = 0; 3349 size_t after = 0; 3350 MetaWord* res; 3351 bool incremented; 3352 3353 // Each thread increments the HWM at most once. Even if the thread fails to increment 3354 // the HWM, an allocation is still attempted. This is because another thread must then 3355 // have incremented the HWM and therefore the allocation might still succeed. 3356 do { 3357 incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before); 3358 res = allocate(word_size, mdtype); 3359 } while (!incremented && res == NULL); 3360 3361 if (incremented) { 3362 tracer()->report_gc_threshold(before, after, 3363 MetaspaceGCThresholdUpdater::ExpandAndAllocate); 3364 log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after); 3365 } 3366 3367 return res; 3368 } 3369 3370 // Space allocated in the Metaspace. This may 3371 // be across several metadata virtual spaces. 3372 char* Metaspace::bottom() const { 3373 assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces"); 3374 return (char*)vsm()->current_chunk()->bottom(); 3375 } 3376 3377 size_t Metaspace::used_words_slow(MetadataType mdtype) const { 3378 if (mdtype == ClassType) { 3379 return using_class_space() ? class_vsm()->sum_used_in_chunks_in_use() : 0; 3380 } else { 3381 return vsm()->sum_used_in_chunks_in_use(); // includes overhead! 3382 } 3383 } 3384 3385 size_t Metaspace::free_words_slow(MetadataType mdtype) const { 3386 if (mdtype == ClassType) { 3387 return using_class_space() ? class_vsm()->sum_free_in_chunks_in_use() : 0; 3388 } else { 3389 return vsm()->sum_free_in_chunks_in_use(); 3390 } 3391 } 3392 3393 // Space capacity in the Metaspace. It includes 3394 // space in the list of chunks from which allocations 3395 // have been made. Don't include space in the global freelist and 3396 // in the space available in the dictionary which 3397 // is already counted in some chunk. 3398 size_t Metaspace::capacity_words_slow(MetadataType mdtype) const { 3399 if (mdtype == ClassType) { 3400 return using_class_space() ? class_vsm()->sum_capacity_in_chunks_in_use() : 0; 3401 } else { 3402 return vsm()->sum_capacity_in_chunks_in_use(); 3403 } 3404 } 3405 3406 size_t Metaspace::used_bytes_slow(MetadataType mdtype) const { 3407 return used_words_slow(mdtype) * BytesPerWord; 3408 } 3409 3410 size_t Metaspace::capacity_bytes_slow(MetadataType mdtype) const { 3411 return capacity_words_slow(mdtype) * BytesPerWord; 3412 } 3413 3414 size_t Metaspace::allocated_blocks_bytes() const { 3415 return vsm()->allocated_blocks_bytes() + 3416 (using_class_space() ? class_vsm()->allocated_blocks_bytes() : 0); 3417 } 3418 3419 size_t Metaspace::allocated_chunks_bytes() const { 3420 return vsm()->allocated_chunks_bytes() + 3421 (using_class_space() ? class_vsm()->allocated_chunks_bytes() : 0); 3422 } 3423 3424 void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) { 3425 assert(!SafepointSynchronize::is_at_safepoint() 3426 || Thread::current()->is_VM_thread(), "should be the VM thread"); 3427 3428 if (DumpSharedSpaces && PrintSharedSpaces) { 3429 record_deallocation(ptr, vsm()->get_raw_word_size(word_size)); 3430 } 3431 3432 MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag); 3433 3434 if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::min_size()) { 3435 // Dark matter. Too small for dictionary. 3436 #ifdef ASSERT 3437 Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5); 3438 #endif 3439 return; 3440 } 3441 if (is_class && using_class_space()) { 3442 class_vsm()->deallocate(ptr, word_size); 3443 } else { 3444 vsm()->deallocate(ptr, word_size); 3445 } 3446 } 3447 3448 3449 MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size, 3450 bool read_only, MetaspaceObj::Type type, TRAPS) { 3451 if (HAS_PENDING_EXCEPTION) { 3452 assert(false, "Should not allocate with exception pending"); 3453 return NULL; // caller does a CHECK_NULL too 3454 } 3455 3456 assert(loader_data != NULL, "Should never pass around a NULL loader_data. " 3457 "ClassLoaderData::the_null_class_loader_data() should have been used."); 3458 3459 // Allocate in metaspaces without taking out a lock, because it deadlocks 3460 // with the SymbolTable_lock. Dumping is single threaded for now. We'll have 3461 // to revisit this for application class data sharing. 3462 if (DumpSharedSpaces) { 3463 assert(type > MetaspaceObj::UnknownType && type < MetaspaceObj::_number_of_types, "sanity"); 3464 Metaspace* space = read_only ? loader_data->ro_metaspace() : loader_data->rw_metaspace(); 3465 MetaWord* result = space->allocate(word_size, NonClassType); 3466 if (result == NULL) { 3467 report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite); 3468 } 3469 if (PrintSharedSpaces) { 3470 space->record_allocation(result, type, space->vsm()->get_raw_word_size(word_size)); 3471 } 3472 3473 // Zero initialize. 3474 Copy::fill_to_words((HeapWord*)result, word_size, 0); 3475 3476 return result; 3477 } 3478 3479 MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType; 3480 3481 // Try to allocate metadata. 3482 MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype); 3483 3484 if (result == NULL) { 3485 tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype); 3486 3487 // Allocation failed. 3488 if (is_init_completed()) { 3489 // Only start a GC if the bootstrapping has completed. 3490 3491 // Try to clean out some memory and retry. 3492 result = Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation( 3493 loader_data, word_size, mdtype); 3494 } 3495 } 3496 3497 if (result == NULL) { 3498 SpaceManager* sm; 3499 if (is_class_space_allocation(mdtype)) { 3500 sm = loader_data->metaspace_non_null()->class_vsm(); 3501 } else { 3502 sm = loader_data->metaspace_non_null()->vsm(); 3503 } 3504 3505 result = sm->get_small_chunk_and_allocate(word_size); 3506 3507 if (result == NULL) { 3508 report_metadata_oome(loader_data, word_size, type, mdtype, CHECK_NULL); 3509 } 3510 } 3511 3512 // Zero initialize. 3513 Copy::fill_to_words((HeapWord*)result, word_size, 0); 3514 3515 return result; 3516 } 3517 3518 size_t Metaspace::class_chunk_size(size_t word_size) { 3519 assert(using_class_space(), "Has to use class space"); 3520 return class_vsm()->calc_chunk_size(word_size); 3521 } 3522 3523 void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) { 3524 tracer()->report_metadata_oom(loader_data, word_size, type, mdtype); 3525 3526 // If result is still null, we are out of memory. 3527 LogHandle(gc, metaspace, freelist) log; 3528 if (log.is_trace()) { 3529 log.trace("Metaspace allocation failed for size " SIZE_FORMAT, word_size); 3530 ResourceMark rm; 3531 outputStream* out = log.trace_stream(); 3532 if (loader_data->metaspace_or_null() != NULL) { 3533 loader_data->dump(out); 3534 } 3535 MetaspaceAux::dump(out); 3536 } 3537 3538 bool out_of_compressed_class_space = false; 3539 if (is_class_space_allocation(mdtype)) { 3540 Metaspace* metaspace = loader_data->metaspace_non_null(); 3541 out_of_compressed_class_space = 3542 MetaspaceAux::committed_bytes(Metaspace::ClassType) + 3543 (metaspace->class_chunk_size(word_size) * BytesPerWord) > 3544 CompressedClassSpaceSize; 3545 } 3546 3547 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support 3548 const char* space_string = out_of_compressed_class_space ? 3549 "Compressed class space" : "Metaspace"; 3550 3551 report_java_out_of_memory(space_string); 3552 3553 if (JvmtiExport::should_post_resource_exhausted()) { 3554 JvmtiExport::post_resource_exhausted( 3555 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR, 3556 space_string); 3557 } 3558 3559 if (!is_init_completed()) { 3560 vm_exit_during_initialization("OutOfMemoryError", space_string); 3561 } 3562 3563 if (out_of_compressed_class_space) { 3564 THROW_OOP(Universe::out_of_memory_error_class_metaspace()); 3565 } else { 3566 THROW_OOP(Universe::out_of_memory_error_metaspace()); 3567 } 3568 } 3569 3570 const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) { 3571 switch (mdtype) { 3572 case Metaspace::ClassType: return "Class"; 3573 case Metaspace::NonClassType: return "Metadata"; 3574 default: 3575 assert(false, "Got bad mdtype: %d", (int) mdtype); 3576 return NULL; 3577 } 3578 } 3579 3580 void Metaspace::record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size) { 3581 assert(DumpSharedSpaces, "sanity"); 3582 3583 int byte_size = (int)word_size * wordSize; 3584 AllocRecord *rec = new AllocRecord((address)ptr, type, byte_size); 3585 3586 if (_alloc_record_head == NULL) { 3587 _alloc_record_head = _alloc_record_tail = rec; 3588 } else if (_alloc_record_tail->_ptr + _alloc_record_tail->_byte_size == (address)ptr) { 3589 _alloc_record_tail->_next = rec; 3590 _alloc_record_tail = rec; 3591 } else { 3592 // slow linear search, but this doesn't happen that often, and only when dumping 3593 for (AllocRecord *old = _alloc_record_head; old; old = old->_next) { 3594 if (old->_ptr == ptr) { 3595 assert(old->_type == MetaspaceObj::DeallocatedType, "sanity"); 3596 int remain_bytes = old->_byte_size - byte_size; 3597 assert(remain_bytes >= 0, "sanity"); 3598 old->_type = type; 3599 3600 if (remain_bytes == 0) { 3601 delete(rec); 3602 } else { 3603 address remain_ptr = address(ptr) + byte_size; 3604 rec->_ptr = remain_ptr; 3605 rec->_byte_size = remain_bytes; 3606 rec->_type = MetaspaceObj::DeallocatedType; 3607 rec->_next = old->_next; 3608 old->_byte_size = byte_size; 3609 old->_next = rec; 3610 } 3611 return; 3612 } 3613 } 3614 assert(0, "reallocating a freed pointer that was not recorded"); 3615 } 3616 } 3617 3618 void Metaspace::record_deallocation(void* ptr, size_t word_size) { 3619 assert(DumpSharedSpaces, "sanity"); 3620 3621 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) { 3622 if (rec->_ptr == ptr) { 3623 assert(rec->_byte_size == (int)word_size * wordSize, "sanity"); 3624 rec->_type = MetaspaceObj::DeallocatedType; 3625 return; 3626 } 3627 } 3628 3629 assert(0, "deallocating a pointer that was not recorded"); 3630 } 3631 3632 void Metaspace::iterate(Metaspace::AllocRecordClosure *closure) { 3633 assert(DumpSharedSpaces, "unimplemented for !DumpSharedSpaces"); 3634 3635 address last_addr = (address)bottom(); 3636 3637 for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) { 3638 address ptr = rec->_ptr; 3639 if (last_addr < ptr) { 3640 closure->doit(last_addr, MetaspaceObj::UnknownType, ptr - last_addr); 3641 } 3642 closure->doit(ptr, rec->_type, rec->_byte_size); 3643 last_addr = ptr + rec->_byte_size; 3644 } 3645 3646 address top = ((address)bottom()) + used_bytes_slow(Metaspace::NonClassType); 3647 if (last_addr < top) { 3648 closure->doit(last_addr, MetaspaceObj::UnknownType, top - last_addr); 3649 } 3650 } 3651 3652 void Metaspace::purge(MetadataType mdtype) { 3653 get_space_list(mdtype)->purge(get_chunk_manager(mdtype)); 3654 } 3655 3656 void Metaspace::purge() { 3657 MutexLockerEx cl(SpaceManager::expand_lock(), 3658 Mutex::_no_safepoint_check_flag); 3659 purge(NonClassType); 3660 if (using_class_space()) { 3661 purge(ClassType); 3662 } 3663 } 3664 3665 void Metaspace::print_on(outputStream* out) const { 3666 // Print both class virtual space counts and metaspace. 3667 if (Verbose) { 3668 vsm()->print_on(out); 3669 if (using_class_space()) { 3670 class_vsm()->print_on(out); 3671 } 3672 } 3673 } 3674 3675 bool Metaspace::contains(const void* ptr) { 3676 if (UseSharedSpaces && MetaspaceShared::is_in_shared_space(ptr)) { 3677 return true; 3678 } 3679 3680 if (using_class_space() && get_space_list(ClassType)->contains(ptr)) { 3681 return true; 3682 } 3683 3684 return get_space_list(NonClassType)->contains(ptr); 3685 } 3686 3687 void Metaspace::verify() { 3688 vsm()->verify(); 3689 if (using_class_space()) { 3690 class_vsm()->verify(); 3691 } 3692 } 3693 3694 void Metaspace::dump(outputStream* const out) const { 3695 out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, p2i(vsm())); 3696 vsm()->dump(out); 3697 if (using_class_space()) { 3698 out->print_cr("\nClass space manager: " INTPTR_FORMAT, p2i(class_vsm())); 3699 class_vsm()->dump(out); 3700 } 3701 } 3702 3703 /////////////// Unit tests /////////////// 3704 3705 #ifndef PRODUCT 3706 3707 class TestMetaspaceAuxTest : AllStatic { 3708 public: 3709 static void test_reserved() { 3710 size_t reserved = MetaspaceAux::reserved_bytes(); 3711 3712 assert(reserved > 0, "assert"); 3713 3714 size_t committed = MetaspaceAux::committed_bytes(); 3715 assert(committed <= reserved, "assert"); 3716 3717 size_t reserved_metadata = MetaspaceAux::reserved_bytes(Metaspace::NonClassType); 3718 assert(reserved_metadata > 0, "assert"); 3719 assert(reserved_metadata <= reserved, "assert"); 3720 3721 if (UseCompressedClassPointers) { 3722 size_t reserved_class = MetaspaceAux::reserved_bytes(Metaspace::ClassType); 3723 assert(reserved_class > 0, "assert"); 3724 assert(reserved_class < reserved, "assert"); 3725 } 3726 } 3727 3728 static void test_committed() { 3729 size_t committed = MetaspaceAux::committed_bytes(); 3730 3731 assert(committed > 0, "assert"); 3732 3733 size_t reserved = MetaspaceAux::reserved_bytes(); 3734 assert(committed <= reserved, "assert"); 3735 3736 size_t committed_metadata = MetaspaceAux::committed_bytes(Metaspace::NonClassType); 3737 assert(committed_metadata > 0, "assert"); 3738 assert(committed_metadata <= committed, "assert"); 3739 3740 if (UseCompressedClassPointers) { 3741 size_t committed_class = MetaspaceAux::committed_bytes(Metaspace::ClassType); 3742 assert(committed_class > 0, "assert"); 3743 assert(committed_class < committed, "assert"); 3744 } 3745 } 3746 3747 static void test_virtual_space_list_large_chunk() { 3748 VirtualSpaceList* vs_list = new VirtualSpaceList(os::vm_allocation_granularity()); 3749 MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3750 // A size larger than VirtualSpaceSize (256k) and add one page to make it _not_ be 3751 // vm_allocation_granularity aligned on Windows. 3752 size_t large_size = (size_t)(2*256*K + (os::vm_page_size()/BytesPerWord)); 3753 large_size += (os::vm_page_size()/BytesPerWord); 3754 vs_list->get_new_chunk(large_size, large_size, 0); 3755 } 3756 3757 static void test() { 3758 test_reserved(); 3759 test_committed(); 3760 test_virtual_space_list_large_chunk(); 3761 } 3762 }; 3763 3764 void TestMetaspaceAux_test() { 3765 TestMetaspaceAuxTest::test(); 3766 } 3767 3768 class TestVirtualSpaceNodeTest { 3769 static void chunk_up(size_t words_left, size_t& num_medium_chunks, 3770 size_t& num_small_chunks, 3771 size_t& num_specialized_chunks) { 3772 num_medium_chunks = words_left / MediumChunk; 3773 words_left = words_left % MediumChunk; 3774 3775 num_small_chunks = words_left / SmallChunk; 3776 words_left = words_left % SmallChunk; 3777 // how many specialized chunks can we get? 3778 num_specialized_chunks = words_left / SpecializedChunk; 3779 assert(words_left % SpecializedChunk == 0, "should be nothing left"); 3780 } 3781 3782 public: 3783 static void test() { 3784 MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); 3785 const size_t vsn_test_size_words = MediumChunk * 4; 3786 const size_t vsn_test_size_bytes = vsn_test_size_words * BytesPerWord; 3787 3788 // The chunk sizes must be multiples of eachother, or this will fail 3789 STATIC_ASSERT(MediumChunk % SmallChunk == 0); 3790 STATIC_ASSERT(SmallChunk % SpecializedChunk == 0); 3791 3792 { // No committed memory in VSN 3793 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3794 VirtualSpaceNode vsn(vsn_test_size_bytes); 3795 vsn.initialize(); 3796 vsn.retire(&cm); 3797 assert(cm.sum_free_chunks_count() == 0, "did not commit any memory in the VSN"); 3798 } 3799 3800 { // All of VSN is committed, half is used by chunks 3801 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3802 VirtualSpaceNode vsn(vsn_test_size_bytes); 3803 vsn.initialize(); 3804 vsn.expand_by(vsn_test_size_words, vsn_test_size_words); 3805 vsn.get_chunk_vs(MediumChunk); 3806 vsn.get_chunk_vs(MediumChunk); 3807 vsn.retire(&cm); 3808 assert(cm.sum_free_chunks_count() == 2, "should have been memory left for 2 medium chunks"); 3809 assert(cm.sum_free_chunks() == 2*MediumChunk, "sizes should add up"); 3810 } 3811 3812 const size_t page_chunks = 4 * (size_t)os::vm_page_size() / BytesPerWord; 3813 // This doesn't work for systems with vm_page_size >= 16K. 3814 if (page_chunks < MediumChunk) { 3815 // 4 pages of VSN is committed, some is used by chunks 3816 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3817 VirtualSpaceNode vsn(vsn_test_size_bytes); 3818 3819 vsn.initialize(); 3820 vsn.expand_by(page_chunks, page_chunks); 3821 vsn.get_chunk_vs(SmallChunk); 3822 vsn.get_chunk_vs(SpecializedChunk); 3823 vsn.retire(&cm); 3824 3825 // committed - used = words left to retire 3826 const size_t words_left = page_chunks - SmallChunk - SpecializedChunk; 3827 3828 size_t num_medium_chunks, num_small_chunks, num_spec_chunks; 3829 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks); 3830 3831 assert(num_medium_chunks == 0, "should not get any medium chunks"); 3832 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks"); 3833 assert(cm.sum_free_chunks() == words_left, "sizes should add up"); 3834 } 3835 3836 { // Half of VSN is committed, a humongous chunk is used 3837 ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk); 3838 VirtualSpaceNode vsn(vsn_test_size_bytes); 3839 vsn.initialize(); 3840 vsn.expand_by(MediumChunk * 2, MediumChunk * 2); 3841 vsn.get_chunk_vs(MediumChunk + SpecializedChunk); // Humongous chunks will be aligned up to MediumChunk + SpecializedChunk 3842 vsn.retire(&cm); 3843 3844 const size_t words_left = MediumChunk * 2 - (MediumChunk + SpecializedChunk); 3845 size_t num_medium_chunks, num_small_chunks, num_spec_chunks; 3846 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks); 3847 3848 assert(num_medium_chunks == 0, "should not get any medium chunks"); 3849 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks"); 3850 assert(cm.sum_free_chunks() == words_left, "sizes should add up"); 3851 } 3852 3853 } 3854 3855 #define assert_is_available_positive(word_size) \ 3856 assert(vsn.is_available(word_size), \ 3857 #word_size ": " PTR_FORMAT " bytes were not available in " \ 3858 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \ 3859 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())); 3860 3861 #define assert_is_available_negative(word_size) \ 3862 assert(!vsn.is_available(word_size), \ 3863 #word_size ": " PTR_FORMAT " bytes should not be available in " \ 3864 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \ 3865 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())); 3866 3867 static void test_is_available_positive() { 3868 // Reserve some memory. 3869 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 3870 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 3871 3872 // Commit some memory. 3873 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 3874 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 3875 assert(expanded, "Failed to commit"); 3876 3877 // Check that is_available accepts the committed size. 3878 assert_is_available_positive(commit_word_size); 3879 3880 // Check that is_available accepts half the committed size. 3881 size_t expand_word_size = commit_word_size / 2; 3882 assert_is_available_positive(expand_word_size); 3883 } 3884 3885 static void test_is_available_negative() { 3886 // Reserve some memory. 3887 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 3888 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 3889 3890 // Commit some memory. 3891 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 3892 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 3893 assert(expanded, "Failed to commit"); 3894 3895 // Check that is_available doesn't accept a too large size. 3896 size_t two_times_commit_word_size = commit_word_size * 2; 3897 assert_is_available_negative(two_times_commit_word_size); 3898 } 3899 3900 static void test_is_available_overflow() { 3901 // Reserve some memory. 3902 VirtualSpaceNode vsn(os::vm_allocation_granularity()); 3903 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 3904 3905 // Commit some memory. 3906 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 3907 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 3908 assert(expanded, "Failed to commit"); 3909 3910 // Calculate a size that will overflow the virtual space size. 3911 void* virtual_space_max = (void*)(uintptr_t)-1; 3912 size_t bottom_to_max = pointer_delta(virtual_space_max, vsn.bottom(), 1); 3913 size_t overflow_size = bottom_to_max + BytesPerWord; 3914 size_t overflow_word_size = overflow_size / BytesPerWord; 3915 3916 // Check that is_available can handle the overflow. 3917 assert_is_available_negative(overflow_word_size); 3918 } 3919 3920 static void test_is_available() { 3921 TestVirtualSpaceNodeTest::test_is_available_positive(); 3922 TestVirtualSpaceNodeTest::test_is_available_negative(); 3923 TestVirtualSpaceNodeTest::test_is_available_overflow(); 3924 } 3925 }; 3926 3927 void TestVirtualSpaceNode_test() { 3928 TestVirtualSpaceNodeTest::test(); 3929 TestVirtualSpaceNodeTest::test_is_available(); 3930 } 3931 #endif