1 /* 2 * Copyright (c) 2011, 2018, 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 "aot/aotLoader.hpp" 26 #include "gc/shared/collectedHeap.hpp" 27 #include "gc/shared/collectorPolicy.hpp" 28 #include "logging/log.hpp" 29 #include "logging/logStream.hpp" 30 #include "memory/allocation.hpp" 31 #include "memory/binaryTreeDictionary.inline.hpp" 32 #include "memory/filemap.hpp" 33 #include "memory/freeList.inline.hpp" 34 #include "memory/metachunk.hpp" 35 #include "memory/metaspace.hpp" 36 #include "memory/metaspace/metaspaceCommon.hpp" 37 #include "memory/metaspace/metaspaceStatistics.hpp" 38 #include "memory/metaspaceGCThresholdUpdater.hpp" 39 #include "memory/metaspaceShared.hpp" 40 #include "memory/metaspaceTracer.hpp" 41 #include "memory/resourceArea.hpp" 42 #include "memory/universe.hpp" 43 #include "runtime/atomic.hpp" 44 #include "runtime/globals.hpp" 45 #include "runtime/init.hpp" 46 #include "runtime/java.hpp" 47 #include "runtime/mutex.hpp" 48 #include "runtime/mutexLocker.hpp" 49 #include "runtime/orderAccess.inline.hpp" 50 #include "services/memTracker.hpp" 51 #include "services/memoryService.hpp" 52 #include "utilities/align.hpp" 53 #include "utilities/copy.hpp" 54 #include "utilities/debug.hpp" 55 #include "utilities/globalDefinitions.hpp" 56 #include "utilities/macros.hpp" 57 58 using namespace metaspace::internals; 59 60 typedef BinaryTreeDictionary<Metablock, FreeList<Metablock> > BlockTreeDictionary; 61 typedef BinaryTreeDictionary<Metachunk, FreeList<Metachunk> > ChunkTreeDictionary; 62 63 // Helper function that does a bunch of checks for a chunk. 64 DEBUG_ONLY(static void do_verify_chunk(Metachunk* chunk);) 65 66 // Given a Metachunk, update its in-use information (both in the 67 // chunk and the occupancy map). 68 static void do_update_in_use_info_for_chunk(Metachunk* chunk, bool inuse); 69 70 size_t const allocation_from_dictionary_limit = 4 * K; 71 72 MetaWord* last_allocated = 0; 73 74 size_t Metaspace::_compressed_class_space_size; 75 const MetaspaceTracer* Metaspace::_tracer = NULL; 76 77 DEBUG_ONLY(bool Metaspace::_frozen = false;) 78 79 // Internal statistics. 80 #ifdef ASSERT 81 static struct { 82 // Number of allocations. 83 uintx num_allocs; 84 // Number of times a ClassLoaderMetaspace was born... 85 uintx num_metaspace_births; 86 // ... and died. 87 uintx num_metaspace_deaths; 88 // Number of times VirtualSpaceListNodes were created... 89 uintx num_vsnodes_created; 90 // ... and purged. 91 uintx num_vsnodes_purged; 92 // Number of times we expanded the committed section of the space. 93 uintx num_committed_space_expanded; 94 // Number of deallocations 95 uintx num_deallocs; 96 // Number of deallocations triggered from outside ("real" deallocations). 97 uintx num_external_deallocs; 98 // Number of times an allocation was satisfied from deallocated blocks. 99 uintx num_allocs_from_deallocated_blocks; 100 } g_internal_statistics; 101 #endif 102 103 enum ChunkSizes { // in words. 104 ClassSpecializedChunk = 128, 105 SpecializedChunk = 128, 106 ClassSmallChunk = 256, 107 SmallChunk = 512, 108 ClassMediumChunk = 4 * K, 109 MediumChunk = 8 * K 110 }; 111 112 // Returns size of this chunk type. 113 size_t get_size_for_nonhumongous_chunktype(ChunkIndex chunktype, bool is_class) { 114 assert(is_valid_nonhumongous_chunktype(chunktype), "invalid chunk type."); 115 size_t size = 0; 116 if (is_class) { 117 switch(chunktype) { 118 case SpecializedIndex: size = ClassSpecializedChunk; break; 119 case SmallIndex: size = ClassSmallChunk; break; 120 case MediumIndex: size = ClassMediumChunk; break; 121 default: 122 ShouldNotReachHere(); 123 } 124 } else { 125 switch(chunktype) { 126 case SpecializedIndex: size = SpecializedChunk; break; 127 case SmallIndex: size = SmallChunk; break; 128 case MediumIndex: size = MediumChunk; break; 129 default: 130 ShouldNotReachHere(); 131 } 132 } 133 return size; 134 } 135 136 ChunkIndex get_chunk_type_by_size(size_t size, bool is_class) { 137 if (is_class) { 138 if (size == ClassSpecializedChunk) { 139 return SpecializedIndex; 140 } else if (size == ClassSmallChunk) { 141 return SmallIndex; 142 } else if (size == ClassMediumChunk) { 143 return MediumIndex; 144 } else if (size > ClassMediumChunk) { 145 // A valid humongous chunk size is a multiple of the smallest chunk size. 146 assert(is_aligned(size, ClassSpecializedChunk), "Invalid chunk size"); 147 return HumongousIndex; 148 } 149 } else { 150 if (size == SpecializedChunk) { 151 return SpecializedIndex; 152 } else if (size == SmallChunk) { 153 return SmallIndex; 154 } else if (size == MediumChunk) { 155 return MediumIndex; 156 } else if (size > MediumChunk) { 157 // A valid humongous chunk size is a multiple of the smallest chunk size. 158 assert(is_aligned(size, SpecializedChunk), "Invalid chunk size"); 159 return HumongousIndex; 160 } 161 } 162 ShouldNotReachHere(); 163 return (ChunkIndex)-1; 164 } 165 166 ChunkIndex next_chunk_index(ChunkIndex i) { 167 assert(i < NumberOfInUseLists, "Out of bound"); 168 return (ChunkIndex) (i+1); 169 } 170 171 ChunkIndex prev_chunk_index(ChunkIndex i) { 172 assert(i > ZeroIndex, "Out of bound"); 173 return (ChunkIndex) (i-1); 174 } 175 176 static const char* space_type_name(Metaspace::MetaspaceType t) { 177 const char* s = NULL; 178 switch (t) { 179 case Metaspace::StandardMetaspaceType: s = "Standard"; break; 180 case Metaspace::BootMetaspaceType: s = "Boot"; break; 181 case Metaspace::AnonymousMetaspaceType: s = "Anonymous"; break; 182 case Metaspace::ReflectionMetaspaceType: s = "Reflection"; break; 183 default: ShouldNotReachHere(); 184 } 185 return s; 186 } 187 188 volatile intptr_t MetaspaceGC::_capacity_until_GC = 0; 189 uint MetaspaceGC::_shrink_factor = 0; 190 bool MetaspaceGC::_should_concurrent_collect = false; 191 192 193 typedef class FreeList<Metachunk> ChunkList; 194 195 // Manages the global free lists of chunks. 196 class ChunkManager : public CHeapObj<mtInternal> { 197 friend class TestVirtualSpaceNodeTest; 198 199 // Free list of chunks of different sizes. 200 // SpecializedChunk 201 // SmallChunk 202 // MediumChunk 203 ChunkList _free_chunks[NumberOfFreeLists]; 204 205 // Whether or not this is the class chunkmanager. 206 const bool _is_class; 207 208 // Return non-humongous chunk list by its index. 209 ChunkList* free_chunks(ChunkIndex index); 210 211 // Returns non-humongous chunk list for the given chunk word size. 212 ChunkList* find_free_chunks_list(size_t word_size); 213 214 // HumongousChunk 215 ChunkTreeDictionary _humongous_dictionary; 216 217 // Returns the humongous chunk dictionary. 218 ChunkTreeDictionary* humongous_dictionary() { 219 return &_humongous_dictionary; 220 } 221 222 // Size, in metaspace words, of all chunks managed by this ChunkManager 223 size_t _free_chunks_total; 224 // Number of chunks in this ChunkManager 225 size_t _free_chunks_count; 226 227 // Update counters after a chunk was added or removed removed. 228 void account_for_added_chunk(const Metachunk* c); 229 void account_for_removed_chunk(const Metachunk* c); 230 231 // Debug support 232 233 size_t sum_free_chunks(); 234 size_t sum_free_chunks_count(); 235 236 void locked_verify_free_chunks_total(); 237 void slow_locked_verify_free_chunks_total() { 238 if (VerifyMetaspace) { 239 locked_verify_free_chunks_total(); 240 } 241 } 242 void locked_verify_free_chunks_count(); 243 void slow_locked_verify_free_chunks_count() { 244 if (VerifyMetaspace) { 245 locked_verify_free_chunks_count(); 246 } 247 } 248 void verify_free_chunks_count(); 249 250 // Given a pointer to a chunk, attempts to merge it with neighboring 251 // free chunks to form a bigger chunk. Returns true if successful. 252 bool attempt_to_coalesce_around_chunk(Metachunk* chunk, ChunkIndex target_chunk_type); 253 254 // Helper for chunk merging: 255 // Given an address range with 1-n chunks which are all supposed to be 256 // free and hence currently managed by this ChunkManager, remove them 257 // from this ChunkManager and mark them as invalid. 258 // - This does not correct the occupancy map. 259 // - This does not adjust the counters in ChunkManager. 260 // - Does not adjust container count counter in containing VirtualSpaceNode. 261 // Returns number of chunks removed. 262 int remove_chunks_in_area(MetaWord* p, size_t word_size); 263 264 // Helper for chunk splitting: given a target chunk size and a larger free chunk, 265 // split up the larger chunk into n smaller chunks, at least one of which should be 266 // the target chunk of target chunk size. The smaller chunks, including the target 267 // chunk, are returned to the freelist. The pointer to the target chunk is returned. 268 // Note that this chunk is supposed to be removed from the freelist right away. 269 Metachunk* split_chunk(size_t target_chunk_word_size, Metachunk* chunk); 270 271 public: 272 273 ChunkManager(bool is_class) 274 : _is_class(is_class), _free_chunks_total(0), _free_chunks_count(0) { 275 _free_chunks[SpecializedIndex].set_size(get_size_for_nonhumongous_chunktype(SpecializedIndex, is_class)); 276 _free_chunks[SmallIndex].set_size(get_size_for_nonhumongous_chunktype(SmallIndex, is_class)); 277 _free_chunks[MediumIndex].set_size(get_size_for_nonhumongous_chunktype(MediumIndex, is_class)); 278 } 279 280 // Add or delete (return) a chunk to the global freelist. 281 Metachunk* chunk_freelist_allocate(size_t word_size); 282 283 // Map a size to a list index assuming that there are lists 284 // for special, small, medium, and humongous chunks. 285 ChunkIndex list_index(size_t size); 286 287 // Map a given index to the chunk size. 288 size_t size_by_index(ChunkIndex index) const; 289 290 bool is_class() const { return _is_class; } 291 292 // Convenience accessors. 293 size_t medium_chunk_word_size() const { return size_by_index(MediumIndex); } 294 size_t small_chunk_word_size() const { return size_by_index(SmallIndex); } 295 size_t specialized_chunk_word_size() const { return size_by_index(SpecializedIndex); } 296 297 // Take a chunk from the ChunkManager. The chunk is expected to be in 298 // the chunk manager (the freelist if non-humongous, the dictionary if 299 // humongous). 300 void remove_chunk(Metachunk* chunk); 301 302 // Return a single chunk of type index to the ChunkManager. 303 void return_single_chunk(ChunkIndex index, Metachunk* chunk); 304 305 // Add the simple linked list of chunks to the freelist of chunks 306 // of type index. 307 void return_chunk_list(ChunkIndex index, Metachunk* chunk); 308 309 // Total of the space in the free chunks list 310 size_t free_chunks_total_words(); 311 size_t free_chunks_total_bytes(); 312 313 // Number of chunks in the free chunks list 314 size_t free_chunks_count(); 315 316 // Remove from a list by size. Selects list based on size of chunk. 317 Metachunk* free_chunks_get(size_t chunk_word_size); 318 319 #define index_bounds_check(index) \ 320 assert(is_valid_chunktype(index), "Bad index: %d", (int) index) 321 322 size_t num_free_chunks(ChunkIndex index) const { 323 index_bounds_check(index); 324 325 if (index == HumongousIndex) { 326 return _humongous_dictionary.total_free_blocks(); 327 } 328 329 ssize_t count = _free_chunks[index].count(); 330 return count == -1 ? 0 : (size_t) count; 331 } 332 333 size_t size_free_chunks_in_bytes(ChunkIndex index) const { 334 index_bounds_check(index); 335 336 size_t word_size = 0; 337 if (index == HumongousIndex) { 338 word_size = _humongous_dictionary.total_size(); 339 } else { 340 const size_t size_per_chunk_in_words = _free_chunks[index].size(); 341 word_size = size_per_chunk_in_words * num_free_chunks(index); 342 } 343 344 return word_size * BytesPerWord; 345 } 346 347 MetaspaceChunkFreeListSummary chunk_free_list_summary() const { 348 return MetaspaceChunkFreeListSummary(num_free_chunks(SpecializedIndex), 349 num_free_chunks(SmallIndex), 350 num_free_chunks(MediumIndex), 351 num_free_chunks(HumongousIndex), 352 size_free_chunks_in_bytes(SpecializedIndex), 353 size_free_chunks_in_bytes(SmallIndex), 354 size_free_chunks_in_bytes(MediumIndex), 355 size_free_chunks_in_bytes(HumongousIndex)); 356 } 357 358 // Debug support 359 void verify(); 360 void slow_verify() { 361 if (VerifyMetaspace) { 362 verify(); 363 } 364 } 365 void locked_verify(); 366 void slow_locked_verify() { 367 if (VerifyMetaspace) { 368 locked_verify(); 369 } 370 } 371 void verify_free_chunks_total(); 372 373 void locked_print_free_chunks(outputStream* st); 374 void locked_print_sum_free_chunks(outputStream* st); 375 376 void print_on(outputStream* st) const; 377 378 // Fill in current statistic values to the given statistics object. 379 void collect_statistics(ChunkManagerStatistics* out) const; 380 381 }; 382 383 class SmallBlocks : public CHeapObj<mtClass> { 384 const static uint _small_block_max_size = sizeof(TreeChunk<Metablock, FreeList<Metablock> >)/HeapWordSize; 385 // Note: this corresponds to the imposed miminum allocation size, see SpaceManager::get_allocation_word_size() 386 const static uint _small_block_min_size = sizeof(Metablock)/HeapWordSize; 387 388 private: 389 FreeList<Metablock> _small_lists[_small_block_max_size - _small_block_min_size]; 390 391 FreeList<Metablock>& list_at(size_t word_size) { 392 assert(word_size >= _small_block_min_size, "There are no metaspace objects less than %u words", _small_block_min_size); 393 return _small_lists[word_size - _small_block_min_size]; 394 } 395 396 public: 397 SmallBlocks() { 398 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 399 uint k = i - _small_block_min_size; 400 _small_lists[k].set_size(i); 401 } 402 } 403 404 // Returns the total size, in words, of all blocks, across all block sizes. 405 size_t total_size() const { 406 size_t result = 0; 407 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 408 uint k = i - _small_block_min_size; 409 result = result + _small_lists[k].count() * _small_lists[k].size(); 410 } 411 return result; 412 } 413 414 // Returns the total number of all blocks across all block sizes. 415 uintx total_num_blocks() const { 416 uintx result = 0; 417 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 418 uint k = i - _small_block_min_size; 419 result = result + _small_lists[k].count(); 420 } 421 return result; 422 } 423 424 static uint small_block_max_size() { return _small_block_max_size; } 425 static uint small_block_min_size() { return _small_block_min_size; } 426 427 MetaWord* get_block(size_t word_size) { 428 if (list_at(word_size).count() > 0) { 429 MetaWord* new_block = (MetaWord*) list_at(word_size).get_chunk_at_head(); 430 return new_block; 431 } else { 432 return NULL; 433 } 434 } 435 void return_block(Metablock* free_chunk, size_t word_size) { 436 list_at(word_size).return_chunk_at_head(free_chunk, false); 437 assert(list_at(word_size).count() > 0, "Should have a chunk"); 438 } 439 440 void print_on(outputStream* st) const { 441 st->print_cr("SmallBlocks:"); 442 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 443 uint k = i - _small_block_min_size; 444 st->print_cr("small_lists size " SIZE_FORMAT " count " SIZE_FORMAT, _small_lists[k].size(), _small_lists[k].count()); 445 } 446 } 447 }; 448 449 // Used to manage the free list of Metablocks (a block corresponds 450 // to the allocation of a quantum of metadata). 451 class BlockFreelist : public CHeapObj<mtClass> { 452 BlockTreeDictionary* const _dictionary; 453 SmallBlocks* _small_blocks; 454 455 // Only allocate and split from freelist if the size of the allocation 456 // is at least 1/4th the size of the available block. 457 const static int WasteMultiplier = 4; 458 459 // Accessors 460 BlockTreeDictionary* dictionary() const { return _dictionary; } 461 SmallBlocks* small_blocks() { 462 if (_small_blocks == NULL) { 463 _small_blocks = new SmallBlocks(); 464 } 465 return _small_blocks; 466 } 467 468 public: 469 BlockFreelist(); 470 ~BlockFreelist(); 471 472 // Get and return a block to the free list 473 MetaWord* get_block(size_t word_size); 474 void return_block(MetaWord* p, size_t word_size); 475 476 // Returns the total size, in words, of all blocks kept in this structure. 477 size_t total_size() const { 478 size_t result = dictionary()->total_size(); 479 if (_small_blocks != NULL) { 480 result = result + _small_blocks->total_size(); 481 } 482 return result; 483 } 484 485 // Returns the number of all blocks kept in this structure. 486 uintx num_blocks() const { 487 uintx result = dictionary()->total_free_blocks(); 488 if (_small_blocks != NULL) { 489 result = result + _small_blocks->total_num_blocks(); 490 } 491 return result; 492 } 493 494 static size_t min_dictionary_size() { return TreeChunk<Metablock, FreeList<Metablock> >::min_size(); } 495 void print_on(outputStream* st) const; 496 }; 497 498 // Helper for Occupancy Bitmap. A type trait to give an all-bits-are-one-unsigned constant. 499 template <typename T> struct all_ones { static const T value; }; 500 template <> struct all_ones <uint64_t> { static const uint64_t value = 0xFFFFFFFFFFFFFFFFULL; }; 501 template <> struct all_ones <uint32_t> { static const uint32_t value = 0xFFFFFFFF; }; 502 503 // The OccupancyMap is a bitmap which, for a given VirtualSpaceNode, 504 // keeps information about 505 // - where a chunk starts 506 // - whether a chunk is in-use or free 507 // A bit in this bitmap represents one range of memory in the smallest 508 // chunk size (SpecializedChunk or ClassSpecializedChunk). 509 class OccupancyMap : public CHeapObj<mtInternal> { 510 511 // The address range this map covers. 512 const MetaWord* const _reference_address; 513 const size_t _word_size; 514 515 // The word size of a specialized chunk, aka the number of words one 516 // bit in this map represents. 517 const size_t _smallest_chunk_word_size; 518 519 // map data 520 // Data are organized in two bit layers: 521 // The first layer is the chunk-start-map. Here, a bit is set to mark 522 // the corresponding region as the head of a chunk. 523 // The second layer is the in-use-map. Here, a set bit indicates that 524 // the corresponding belongs to a chunk which is in use. 525 uint8_t* _map[2]; 526 527 enum { layer_chunk_start_map = 0, layer_in_use_map = 1 }; 528 529 // length, in bytes, of bitmap data 530 size_t _map_size; 531 532 // Returns true if bit at position pos at bit-layer layer is set. 533 bool get_bit_at_position(unsigned pos, unsigned layer) const { 534 assert(layer == 0 || layer == 1, "Invalid layer %d", layer); 535 const unsigned byteoffset = pos / 8; 536 assert(byteoffset < _map_size, 537 "invalid byte offset (%u), map size is " SIZE_FORMAT ".", byteoffset, _map_size); 538 const unsigned mask = 1 << (pos % 8); 539 return (_map[layer][byteoffset] & mask) > 0; 540 } 541 542 // Changes bit at position pos at bit-layer layer to value v. 543 void set_bit_at_position(unsigned pos, unsigned layer, bool v) { 544 assert(layer == 0 || layer == 1, "Invalid layer %d", layer); 545 const unsigned byteoffset = pos / 8; 546 assert(byteoffset < _map_size, 547 "invalid byte offset (%u), map size is " SIZE_FORMAT ".", byteoffset, _map_size); 548 const unsigned mask = 1 << (pos % 8); 549 if (v) { 550 _map[layer][byteoffset] |= mask; 551 } else { 552 _map[layer][byteoffset] &= ~mask; 553 } 554 } 555 556 // Optimized case of is_any_bit_set_in_region for 32/64bit aligned access: 557 // pos is 32/64 aligned and num_bits is 32/64. 558 // This is the typical case when coalescing to medium chunks, whose size is 559 // 32 or 64 times the specialized chunk size (depending on class or non class 560 // case), so they occupy 64 bits which should be 64bit aligned, because 561 // chunks are chunk-size aligned. 562 template <typename T> 563 bool is_any_bit_set_in_region_3264(unsigned pos, unsigned num_bits, unsigned layer) const { 564 assert(_map_size > 0, "not initialized"); 565 assert(layer == 0 || layer == 1, "Invalid layer %d.", layer); 566 assert(pos % (sizeof(T) * 8) == 0, "Bit position must be aligned (%u).", pos); 567 assert(num_bits == (sizeof(T) * 8), "Number of bits incorrect (%u).", num_bits); 568 const size_t byteoffset = pos / 8; 569 assert(byteoffset <= (_map_size - sizeof(T)), 570 "Invalid byte offset (" SIZE_FORMAT "), map size is " SIZE_FORMAT ".", byteoffset, _map_size); 571 const T w = *(T*)(_map[layer] + byteoffset); 572 return w > 0 ? true : false; 573 } 574 575 // Returns true if any bit in region [pos1, pos1 + num_bits) is set in bit-layer layer. 576 bool is_any_bit_set_in_region(unsigned pos, unsigned num_bits, unsigned layer) const { 577 if (pos % 32 == 0 && num_bits == 32) { 578 return is_any_bit_set_in_region_3264<uint32_t>(pos, num_bits, layer); 579 } else if (pos % 64 == 0 && num_bits == 64) { 580 return is_any_bit_set_in_region_3264<uint64_t>(pos, num_bits, layer); 581 } else { 582 for (unsigned n = 0; n < num_bits; n ++) { 583 if (get_bit_at_position(pos + n, layer)) { 584 return true; 585 } 586 } 587 } 588 return false; 589 } 590 591 // Returns true if any bit in region [p, p+word_size) is set in bit-layer layer. 592 bool is_any_bit_set_in_region(MetaWord* p, size_t word_size, unsigned layer) const { 593 assert(word_size % _smallest_chunk_word_size == 0, 594 "Region size " SIZE_FORMAT " not a multiple of smallest chunk size.", word_size); 595 const unsigned pos = get_bitpos_for_address(p); 596 const unsigned num_bits = (unsigned) (word_size / _smallest_chunk_word_size); 597 return is_any_bit_set_in_region(pos, num_bits, layer); 598 } 599 600 // Optimized case of set_bits_of_region for 32/64bit aligned access: 601 // pos is 32/64 aligned and num_bits is 32/64. 602 // This is the typical case when coalescing to medium chunks, whose size 603 // is 32 or 64 times the specialized chunk size (depending on class or non 604 // class case), so they occupy 64 bits which should be 64bit aligned, 605 // because chunks are chunk-size aligned. 606 template <typename T> 607 void set_bits_of_region_T(unsigned pos, unsigned num_bits, unsigned layer, bool v) { 608 assert(pos % (sizeof(T) * 8) == 0, "Bit position must be aligned to %u (%u).", 609 (unsigned)(sizeof(T) * 8), pos); 610 assert(num_bits == (sizeof(T) * 8), "Number of bits incorrect (%u), expected %u.", 611 num_bits, (unsigned)(sizeof(T) * 8)); 612 const size_t byteoffset = pos / 8; 613 assert(byteoffset <= (_map_size - sizeof(T)), 614 "invalid byte offset (" SIZE_FORMAT "), map size is " SIZE_FORMAT ".", byteoffset, _map_size); 615 T* const pw = (T*)(_map[layer] + byteoffset); 616 *pw = v ? all_ones<T>::value : (T) 0; 617 } 618 619 // Set all bits in a region starting at pos to a value. 620 void set_bits_of_region(unsigned pos, unsigned num_bits, unsigned layer, bool v) { 621 assert(_map_size > 0, "not initialized"); 622 assert(layer == 0 || layer == 1, "Invalid layer %d.", layer); 623 if (pos % 32 == 0 && num_bits == 32) { 624 set_bits_of_region_T<uint32_t>(pos, num_bits, layer, v); 625 } else if (pos % 64 == 0 && num_bits == 64) { 626 set_bits_of_region_T<uint64_t>(pos, num_bits, layer, v); 627 } else { 628 for (unsigned n = 0; n < num_bits; n ++) { 629 set_bit_at_position(pos + n, layer, v); 630 } 631 } 632 } 633 634 // Helper: sets all bits in a region [p, p+word_size). 635 void set_bits_of_region(MetaWord* p, size_t word_size, unsigned layer, bool v) { 636 assert(word_size % _smallest_chunk_word_size == 0, 637 "Region size " SIZE_FORMAT " not a multiple of smallest chunk size.", word_size); 638 const unsigned pos = get_bitpos_for_address(p); 639 const unsigned num_bits = (unsigned) (word_size / _smallest_chunk_word_size); 640 set_bits_of_region(pos, num_bits, layer, v); 641 } 642 643 // Helper: given an address, return the bit position representing that address. 644 unsigned get_bitpos_for_address(const MetaWord* p) const { 645 assert(_reference_address != NULL, "not initialized"); 646 assert(p >= _reference_address && p < _reference_address + _word_size, 647 "Address %p out of range for occupancy map [%p..%p).", 648 p, _reference_address, _reference_address + _word_size); 649 assert(is_aligned(p, _smallest_chunk_word_size * sizeof(MetaWord)), 650 "Address not aligned (%p).", p); 651 const ptrdiff_t d = (p - _reference_address) / _smallest_chunk_word_size; 652 assert(d >= 0 && (size_t)d < _map_size * 8, "Sanity."); 653 return (unsigned) d; 654 } 655 656 public: 657 658 OccupancyMap(const MetaWord* reference_address, size_t word_size, size_t smallest_chunk_word_size) : 659 _reference_address(reference_address), _word_size(word_size), 660 _smallest_chunk_word_size(smallest_chunk_word_size) { 661 assert(reference_address != NULL, "invalid reference address"); 662 assert(is_aligned(reference_address, smallest_chunk_word_size), 663 "Reference address not aligned to smallest chunk size."); 664 assert(is_aligned(word_size, smallest_chunk_word_size), 665 "Word_size shall be a multiple of the smallest chunk size."); 666 // Calculate bitmap size: one bit per smallest_chunk_word_size'd area. 667 size_t num_bits = word_size / smallest_chunk_word_size; 668 _map_size = (num_bits + 7) / 8; 669 assert(_map_size * 8 >= num_bits, "sanity"); 670 _map[0] = (uint8_t*) os::malloc(_map_size, mtInternal); 671 _map[1] = (uint8_t*) os::malloc(_map_size, mtInternal); 672 assert(_map[0] != NULL && _map[1] != NULL, "Occupancy Map: allocation failed."); 673 memset(_map[1], 0, _map_size); 674 memset(_map[0], 0, _map_size); 675 // Sanity test: the first respectively last possible chunk start address in 676 // the covered range shall map to the first and last bit in the bitmap. 677 assert(get_bitpos_for_address(reference_address) == 0, 678 "First chunk address in range must map to fist bit in bitmap."); 679 assert(get_bitpos_for_address(reference_address + word_size - smallest_chunk_word_size) == num_bits - 1, 680 "Last chunk address in range must map to last bit in bitmap."); 681 } 682 683 ~OccupancyMap() { 684 os::free(_map[0]); 685 os::free(_map[1]); 686 } 687 688 // Returns true if at address x a chunk is starting. 689 bool chunk_starts_at_address(MetaWord* p) const { 690 const unsigned pos = get_bitpos_for_address(p); 691 return get_bit_at_position(pos, layer_chunk_start_map); 692 } 693 694 void set_chunk_starts_at_address(MetaWord* p, bool v) { 695 const unsigned pos = get_bitpos_for_address(p); 696 set_bit_at_position(pos, layer_chunk_start_map, v); 697 } 698 699 // Removes all chunk-start-bits inside a region, typically as a 700 // result of a chunk merge. 701 void wipe_chunk_start_bits_in_region(MetaWord* p, size_t word_size) { 702 set_bits_of_region(p, word_size, layer_chunk_start_map, false); 703 } 704 705 // Returns true if there are life (in use) chunks in the region limited 706 // by [p, p+word_size). 707 bool is_region_in_use(MetaWord* p, size_t word_size) const { 708 return is_any_bit_set_in_region(p, word_size, layer_in_use_map); 709 } 710 711 // Marks the region starting at p with the size word_size as in use 712 // or free, depending on v. 713 void set_region_in_use(MetaWord* p, size_t word_size, bool v) { 714 set_bits_of_region(p, word_size, layer_in_use_map, v); 715 } 716 717 #ifdef ASSERT 718 // Verify occupancy map for the address range [from, to). 719 // We need to tell it the address range, because the memory the 720 // occupancy map is covering may not be fully comitted yet. 721 void verify(MetaWord* from, MetaWord* to) { 722 Metachunk* chunk = NULL; 723 int nth_bit_for_chunk = 0; 724 MetaWord* chunk_end = NULL; 725 for (MetaWord* p = from; p < to; p += _smallest_chunk_word_size) { 726 const unsigned pos = get_bitpos_for_address(p); 727 // Check the chunk-starts-info: 728 if (get_bit_at_position(pos, layer_chunk_start_map)) { 729 // Chunk start marked in bitmap. 730 chunk = (Metachunk*) p; 731 if (chunk_end != NULL) { 732 assert(chunk_end == p, "Unexpected chunk start found at %p (expected " 733 "the next chunk to start at %p).", p, chunk_end); 734 } 735 assert(chunk->is_valid_sentinel(), "Invalid chunk at address %p.", p); 736 if (chunk->get_chunk_type() != HumongousIndex) { 737 guarantee(is_aligned(p, chunk->word_size()), "Chunk %p not aligned.", p); 738 } 739 chunk_end = p + chunk->word_size(); 740 nth_bit_for_chunk = 0; 741 assert(chunk_end <= to, "Chunk end overlaps test address range."); 742 } else { 743 // No chunk start marked in bitmap. 744 assert(chunk != NULL, "Chunk should start at start of address range."); 745 assert(p < chunk_end, "Did not find expected chunk start at %p.", p); 746 nth_bit_for_chunk ++; 747 } 748 // Check the in-use-info: 749 const bool in_use_bit = get_bit_at_position(pos, layer_in_use_map); 750 if (in_use_bit) { 751 assert(!chunk->is_tagged_free(), "Chunk %p: marked in-use in map but is free (bit %u).", 752 chunk, nth_bit_for_chunk); 753 } else { 754 assert(chunk->is_tagged_free(), "Chunk %p: marked free in map but is in use (bit %u).", 755 chunk, nth_bit_for_chunk); 756 } 757 } 758 } 759 760 // Verify that a given chunk is correctly accounted for in the bitmap. 761 void verify_for_chunk(Metachunk* chunk) { 762 assert(chunk_starts_at_address((MetaWord*) chunk), 763 "No chunk start marked in map for chunk %p.", chunk); 764 // For chunks larger than the minimal chunk size, no other chunk 765 // must start in its area. 766 if (chunk->word_size() > _smallest_chunk_word_size) { 767 assert(!is_any_bit_set_in_region(((MetaWord*) chunk) + _smallest_chunk_word_size, 768 chunk->word_size() - _smallest_chunk_word_size, layer_chunk_start_map), 769 "No chunk must start within another chunk."); 770 } 771 if (!chunk->is_tagged_free()) { 772 assert(is_region_in_use((MetaWord*)chunk, chunk->word_size()), 773 "Chunk %p is in use but marked as free in map (%d %d).", 774 chunk, chunk->get_chunk_type(), chunk->get_origin()); 775 } else { 776 assert(!is_region_in_use((MetaWord*)chunk, chunk->word_size()), 777 "Chunk %p is free but marked as in-use in map (%d %d).", 778 chunk, chunk->get_chunk_type(), chunk->get_origin()); 779 } 780 } 781 782 #endif // ASSERT 783 784 }; 785 786 // A VirtualSpaceList node. 787 class VirtualSpaceNode : public CHeapObj<mtClass> { 788 friend class VirtualSpaceList; 789 790 // Link to next VirtualSpaceNode 791 VirtualSpaceNode* _next; 792 793 // Whether this node is contained in class or metaspace. 794 const bool _is_class; 795 796 // total in the VirtualSpace 797 MemRegion _reserved; 798 ReservedSpace _rs; 799 VirtualSpace _virtual_space; 800 MetaWord* _top; 801 // count of chunks contained in this VirtualSpace 802 uintx _container_count; 803 804 OccupancyMap* _occupancy_map; 805 806 // Convenience functions to access the _virtual_space 807 char* low() const { return virtual_space()->low(); } 808 char* high() const { return virtual_space()->high(); } 809 810 // The first Metachunk will be allocated at the bottom of the 811 // VirtualSpace 812 Metachunk* first_chunk() { return (Metachunk*) bottom(); } 813 814 // Committed but unused space in the virtual space 815 size_t free_words_in_vs() const; 816 817 // True if this node belongs to class metaspace. 818 bool is_class() const { return _is_class; } 819 820 // Helper function for take_from_committed: allocate padding chunks 821 // until top is at the given address. 822 void allocate_padding_chunks_until_top_is_at(MetaWord* target_top); 823 824 public: 825 826 VirtualSpaceNode(bool is_class, size_t byte_size); 827 VirtualSpaceNode(bool is_class, ReservedSpace rs) : 828 _is_class(is_class), _top(NULL), _next(NULL), _rs(rs), _container_count(0), _occupancy_map(NULL) {} 829 ~VirtualSpaceNode(); 830 831 // Convenience functions for logical bottom and end 832 MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); } 833 MetaWord* end() const { return (MetaWord*) _virtual_space.high(); } 834 835 const OccupancyMap* occupancy_map() const { return _occupancy_map; } 836 OccupancyMap* occupancy_map() { return _occupancy_map; } 837 838 bool contains(const void* ptr) { return ptr >= low() && ptr < high(); } 839 840 size_t reserved_words() const { return _virtual_space.reserved_size() / BytesPerWord; } 841 size_t committed_words() const { return _virtual_space.actual_committed_size() / BytesPerWord; } 842 843 bool is_pre_committed() const { return _virtual_space.special(); } 844 845 // address of next available space in _virtual_space; 846 // Accessors 847 VirtualSpaceNode* next() { return _next; } 848 void set_next(VirtualSpaceNode* v) { _next = v; } 849 850 void set_reserved(MemRegion const v) { _reserved = v; } 851 void set_top(MetaWord* v) { _top = v; } 852 853 // Accessors 854 MemRegion* reserved() { return &_reserved; } 855 VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; } 856 857 // Returns true if "word_size" is available in the VirtualSpace 858 bool is_available(size_t word_size) { return word_size <= pointer_delta(end(), _top, sizeof(MetaWord)); } 859 860 MetaWord* top() const { return _top; } 861 void inc_top(size_t word_size) { _top += word_size; } 862 863 uintx container_count() { return _container_count; } 864 void inc_container_count(); 865 void dec_container_count(); 866 #ifdef ASSERT 867 uintx container_count_slow(); 868 void verify_container_count(); 869 #endif 870 871 // used and capacity in this single entry in the list 872 size_t used_words_in_vs() const; 873 size_t capacity_words_in_vs() const; 874 875 bool initialize(); 876 877 // get space from the virtual space 878 Metachunk* take_from_committed(size_t chunk_word_size); 879 880 // Allocate a chunk from the virtual space and return it. 881 Metachunk* get_chunk_vs(size_t chunk_word_size); 882 883 // Expands/shrinks the committed space in a virtual space. Delegates 884 // to Virtualspace 885 bool expand_by(size_t min_words, size_t preferred_words); 886 887 // In preparation for deleting this node, remove all the chunks 888 // in the node from any freelist. 889 void purge(ChunkManager* chunk_manager); 890 891 // If an allocation doesn't fit in the current node a new node is created. 892 // Allocate chunks out of the remaining committed space in this node 893 // to avoid wasting that memory. 894 // This always adds up because all the chunk sizes are multiples of 895 // the smallest chunk size. 896 void retire(ChunkManager* chunk_manager); 897 898 899 void print_on(outputStream* st) const { print_on(st, K); } 900 void print_on(outputStream* st, size_t scale) const; 901 void print_map(outputStream* st, bool is_class) const; 902 903 // Debug support 904 DEBUG_ONLY(void mangle();) 905 // Verify counters, all chunks in this list node and the occupancy map. 906 DEBUG_ONLY(void verify();) 907 // Verify that all free chunks in this node are ideally merged 908 // (there not should be multiple small chunks where a large chunk could exist.) 909 DEBUG_ONLY(void verify_free_chunks_are_ideally_merged();) 910 911 }; 912 913 #define assert_is_aligned(value, alignment) \ 914 assert(is_aligned((value), (alignment)), \ 915 SIZE_FORMAT_HEX " is not aligned to " \ 916 SIZE_FORMAT, (size_t)(uintptr_t)value, (alignment)) 917 918 #define assert_counter(expected_value, real_value, msg) \ 919 assert( (expected_value) == (real_value), \ 920 "Counter mismatch (%s): expected " SIZE_FORMAT \ 921 ", but got: " SIZE_FORMAT ".", msg, expected_value, \ 922 real_value); 923 924 // Decide if large pages should be committed when the memory is reserved. 925 static bool should_commit_large_pages_when_reserving(size_t bytes) { 926 if (UseLargePages && UseLargePagesInMetaspace && !os::can_commit_large_page_memory()) { 927 size_t words = bytes / BytesPerWord; 928 bool is_class = false; // We never reserve large pages for the class space. 929 if (MetaspaceGC::can_expand(words, is_class) && 930 MetaspaceGC::allowed_expansion() >= words) { 931 return true; 932 } 933 } 934 935 return false; 936 } 937 938 // byte_size is the size of the associated virtualspace. 939 VirtualSpaceNode::VirtualSpaceNode(bool is_class, size_t bytes) : 940 _is_class(is_class), _top(NULL), _next(NULL), _rs(), _container_count(0), _occupancy_map(NULL) { 941 assert_is_aligned(bytes, Metaspace::reserve_alignment()); 942 bool large_pages = should_commit_large_pages_when_reserving(bytes); 943 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages); 944 945 if (_rs.is_reserved()) { 946 assert(_rs.base() != NULL, "Catch if we get a NULL address"); 947 assert(_rs.size() != 0, "Catch if we get a 0 size"); 948 assert_is_aligned(_rs.base(), Metaspace::reserve_alignment()); 949 assert_is_aligned(_rs.size(), Metaspace::reserve_alignment()); 950 951 MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass); 952 } 953 } 954 955 void VirtualSpaceNode::purge(ChunkManager* chunk_manager) { 956 DEBUG_ONLY(this->verify();) 957 Metachunk* chunk = first_chunk(); 958 Metachunk* invalid_chunk = (Metachunk*) top(); 959 while (chunk < invalid_chunk ) { 960 assert(chunk->is_tagged_free(), "Should be tagged free"); 961 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 962 chunk_manager->remove_chunk(chunk); 963 chunk->remove_sentinel(); 964 assert(chunk->next() == NULL && 965 chunk->prev() == NULL, 966 "Was not removed from its list"); 967 chunk = (Metachunk*) next; 968 } 969 } 970 971 void VirtualSpaceNode::print_map(outputStream* st, bool is_class) const { 972 973 if (bottom() == top()) { 974 return; 975 } 976 977 const size_t spec_chunk_size = is_class ? ClassSpecializedChunk : SpecializedChunk; 978 const size_t small_chunk_size = is_class ? ClassSmallChunk : SmallChunk; 979 const size_t med_chunk_size = is_class ? ClassMediumChunk : MediumChunk; 980 981 int line_len = 100; 982 const size_t section_len = align_up(spec_chunk_size * line_len, med_chunk_size); 983 line_len = (int)(section_len / spec_chunk_size); 984 985 static const int NUM_LINES = 4; 986 987 char* lines[NUM_LINES]; 988 for (int i = 0; i < NUM_LINES; i ++) { 989 lines[i] = (char*)os::malloc(line_len, mtInternal); 990 } 991 int pos = 0; 992 const MetaWord* p = bottom(); 993 const Metachunk* chunk = (const Metachunk*)p; 994 const MetaWord* chunk_end = p + chunk->word_size(); 995 while (p < top()) { 996 if (pos == line_len) { 997 pos = 0; 998 for (int i = 0; i < NUM_LINES; i ++) { 999 st->fill_to(22); 1000 st->print_raw(lines[i], line_len); 1001 st->cr(); 1002 } 1003 } 1004 if (pos == 0) { 1005 st->print(PTR_FORMAT ":", p2i(p)); 1006 } 1007 if (p == chunk_end) { 1008 chunk = (Metachunk*)p; 1009 chunk_end = p + chunk->word_size(); 1010 } 1011 // line 1: chunk starting points (a dot if that area is a chunk start). 1012 lines[0][pos] = p == (const MetaWord*)chunk ? '.' : ' '; 1013 1014 // Line 2: chunk type (x=spec, s=small, m=medium, h=humongous), uppercase if 1015 // chunk is in use. 1016 const bool chunk_is_free = ((Metachunk*)chunk)->is_tagged_free(); 1017 if (chunk->word_size() == spec_chunk_size) { 1018 lines[1][pos] = chunk_is_free ? 'x' : 'X'; 1019 } else if (chunk->word_size() == small_chunk_size) { 1020 lines[1][pos] = chunk_is_free ? 's' : 'S'; 1021 } else if (chunk->word_size() == med_chunk_size) { 1022 lines[1][pos] = chunk_is_free ? 'm' : 'M'; 1023 } else if (chunk->word_size() > med_chunk_size) { 1024 lines[1][pos] = chunk_is_free ? 'h' : 'H'; 1025 } else { 1026 ShouldNotReachHere(); 1027 } 1028 1029 // Line 3: chunk origin 1030 const ChunkOrigin origin = chunk->get_origin(); 1031 lines[2][pos] = origin == origin_normal ? ' ' : '0' + (int) origin; 1032 1033 // Line 4: Virgin chunk? Virgin chunks are chunks created as a byproduct of padding or splitting, 1034 // but were never used. 1035 lines[3][pos] = chunk->get_use_count() > 0 ? ' ' : 'v'; 1036 1037 p += spec_chunk_size; 1038 pos ++; 1039 } 1040 if (pos > 0) { 1041 for (int i = 0; i < NUM_LINES; i ++) { 1042 st->fill_to(22); 1043 st->print_raw(lines[i], line_len); 1044 st->cr(); 1045 } 1046 } 1047 for (int i = 0; i < NUM_LINES; i ++) { 1048 os::free(lines[i]); 1049 } 1050 } 1051 1052 1053 #ifdef ASSERT 1054 uintx VirtualSpaceNode::container_count_slow() { 1055 uintx count = 0; 1056 Metachunk* chunk = first_chunk(); 1057 Metachunk* invalid_chunk = (Metachunk*) top(); 1058 while (chunk < invalid_chunk ) { 1059 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 1060 do_verify_chunk(chunk); 1061 // Don't count the chunks on the free lists. Those are 1062 // still part of the VirtualSpaceNode but not currently 1063 // counted. 1064 if (!chunk->is_tagged_free()) { 1065 count++; 1066 } 1067 chunk = (Metachunk*) next; 1068 } 1069 return count; 1070 } 1071 #endif 1072 1073 #ifdef ASSERT 1074 // Verify counters, all chunks in this list node and the occupancy map. 1075 void VirtualSpaceNode::verify() { 1076 uintx num_in_use_chunks = 0; 1077 Metachunk* chunk = first_chunk(); 1078 Metachunk* invalid_chunk = (Metachunk*) top(); 1079 1080 // Iterate the chunks in this node and verify each chunk. 1081 while (chunk < invalid_chunk ) { 1082 DEBUG_ONLY(do_verify_chunk(chunk);) 1083 if (!chunk->is_tagged_free()) { 1084 num_in_use_chunks ++; 1085 } 1086 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 1087 chunk = (Metachunk*) next; 1088 } 1089 assert(_container_count == num_in_use_chunks, "Container count mismatch (real: " UINTX_FORMAT 1090 ", counter: " UINTX_FORMAT ".", num_in_use_chunks, _container_count); 1091 // Also verify the occupancy map. 1092 occupancy_map()->verify(this->bottom(), this->top()); 1093 } 1094 #endif // ASSERT 1095 1096 #ifdef ASSERT 1097 // Verify that all free chunks in this node are ideally merged 1098 // (there not should be multiple small chunks where a large chunk could exist.) 1099 void VirtualSpaceNode::verify_free_chunks_are_ideally_merged() { 1100 Metachunk* chunk = first_chunk(); 1101 Metachunk* invalid_chunk = (Metachunk*) top(); 1102 // Shorthands. 1103 const size_t size_med = (is_class() ? ClassMediumChunk : MediumChunk) * BytesPerWord; 1104 const size_t size_small = (is_class() ? ClassSmallChunk : SmallChunk) * BytesPerWord; 1105 int num_free_chunks_since_last_med_boundary = -1; 1106 int num_free_chunks_since_last_small_boundary = -1; 1107 while (chunk < invalid_chunk ) { 1108 // Test for missed chunk merge opportunities: count number of free chunks since last chunk boundary. 1109 // Reset the counter when encountering a non-free chunk. 1110 if (chunk->get_chunk_type() != HumongousIndex) { 1111 if (chunk->is_tagged_free()) { 1112 // Count successive free, non-humongous chunks. 1113 if (is_aligned(chunk, size_small)) { 1114 assert(num_free_chunks_since_last_small_boundary <= 1, 1115 "Missed chunk merge opportunity at " PTR_FORMAT " for chunk size " SIZE_FORMAT_HEX ".", p2i(chunk) - size_small, size_small); 1116 num_free_chunks_since_last_small_boundary = 0; 1117 } else if (num_free_chunks_since_last_small_boundary != -1) { 1118 num_free_chunks_since_last_small_boundary ++; 1119 } 1120 if (is_aligned(chunk, size_med)) { 1121 assert(num_free_chunks_since_last_med_boundary <= 1, 1122 "Missed chunk merge opportunity at " PTR_FORMAT " for chunk size " SIZE_FORMAT_HEX ".", p2i(chunk) - size_med, size_med); 1123 num_free_chunks_since_last_med_boundary = 0; 1124 } else if (num_free_chunks_since_last_med_boundary != -1) { 1125 num_free_chunks_since_last_med_boundary ++; 1126 } 1127 } else { 1128 // Encountering a non-free chunk, reset counters. 1129 num_free_chunks_since_last_med_boundary = -1; 1130 num_free_chunks_since_last_small_boundary = -1; 1131 } 1132 } else { 1133 // One cannot merge areas with a humongous chunk in the middle. Reset counters. 1134 num_free_chunks_since_last_med_boundary = -1; 1135 num_free_chunks_since_last_small_boundary = -1; 1136 } 1137 1138 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 1139 chunk = (Metachunk*) next; 1140 } 1141 } 1142 #endif // ASSERT 1143 1144 // List of VirtualSpaces for metadata allocation. 1145 class VirtualSpaceList : public CHeapObj<mtClass> { 1146 friend class VirtualSpaceNode; 1147 1148 enum VirtualSpaceSizes { 1149 VirtualSpaceSize = 256 * K 1150 }; 1151 1152 // Head of the list 1153 VirtualSpaceNode* _virtual_space_list; 1154 // virtual space currently being used for allocations 1155 VirtualSpaceNode* _current_virtual_space; 1156 1157 // Is this VirtualSpaceList used for the compressed class space 1158 bool _is_class; 1159 1160 // Sum of reserved and committed memory in the virtual spaces 1161 size_t _reserved_words; 1162 size_t _committed_words; 1163 1164 // Number of virtual spaces 1165 size_t _virtual_space_count; 1166 1167 ~VirtualSpaceList(); 1168 1169 VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; } 1170 1171 void set_virtual_space_list(VirtualSpaceNode* v) { 1172 _virtual_space_list = v; 1173 } 1174 void set_current_virtual_space(VirtualSpaceNode* v) { 1175 _current_virtual_space = v; 1176 } 1177 1178 void link_vs(VirtualSpaceNode* new_entry); 1179 1180 // Get another virtual space and add it to the list. This 1181 // is typically prompted by a failed attempt to allocate a chunk 1182 // and is typically followed by the allocation of a chunk. 1183 bool create_new_virtual_space(size_t vs_word_size); 1184 1185 // Chunk up the unused committed space in the current 1186 // virtual space and add the chunks to the free list. 1187 void retire_current_virtual_space(); 1188 1189 public: 1190 VirtualSpaceList(size_t word_size); 1191 VirtualSpaceList(ReservedSpace rs); 1192 1193 size_t free_bytes(); 1194 1195 Metachunk* get_new_chunk(size_t chunk_word_size, 1196 size_t suggested_commit_granularity); 1197 1198 bool expand_node_by(VirtualSpaceNode* node, 1199 size_t min_words, 1200 size_t preferred_words); 1201 1202 bool expand_by(size_t min_words, 1203 size_t preferred_words); 1204 1205 VirtualSpaceNode* current_virtual_space() { 1206 return _current_virtual_space; 1207 } 1208 1209 bool is_class() const { return _is_class; } 1210 1211 bool initialization_succeeded() { return _virtual_space_list != NULL; } 1212 1213 size_t reserved_words() { return _reserved_words; } 1214 size_t reserved_bytes() { return reserved_words() * BytesPerWord; } 1215 size_t committed_words() { return _committed_words; } 1216 size_t committed_bytes() { return committed_words() * BytesPerWord; } 1217 1218 void inc_reserved_words(size_t v); 1219 void dec_reserved_words(size_t v); 1220 void inc_committed_words(size_t v); 1221 void dec_committed_words(size_t v); 1222 void inc_virtual_space_count(); 1223 void dec_virtual_space_count(); 1224 1225 bool contains(const void* ptr); 1226 1227 // Unlink empty VirtualSpaceNodes and free it. 1228 void purge(ChunkManager* chunk_manager); 1229 1230 void print_on(outputStream* st) const { print_on(st, K); } 1231 void print_on(outputStream* st, size_t scale) const; 1232 void print_map(outputStream* st) const; 1233 1234 class VirtualSpaceListIterator : public StackObj { 1235 VirtualSpaceNode* _virtual_spaces; 1236 public: 1237 VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) : 1238 _virtual_spaces(virtual_spaces) {} 1239 1240 bool repeat() { 1241 return _virtual_spaces != NULL; 1242 } 1243 1244 VirtualSpaceNode* get_next() { 1245 VirtualSpaceNode* result = _virtual_spaces; 1246 if (_virtual_spaces != NULL) { 1247 _virtual_spaces = _virtual_spaces->next(); 1248 } 1249 return result; 1250 } 1251 }; 1252 }; 1253 1254 class Metadebug : AllStatic { 1255 // Debugging support for Metaspaces 1256 static int _allocation_fail_alot_count; 1257 1258 public: 1259 1260 static void init_allocation_fail_alot_count(); 1261 #ifdef ASSERT 1262 static bool test_metadata_failure(); 1263 #endif 1264 }; 1265 1266 int Metadebug::_allocation_fail_alot_count = 0; 1267 1268 1269 // SpaceManager - used by Metaspace to handle allocations 1270 class SpaceManager : public CHeapObj<mtClass> { 1271 friend class ClassLoaderMetaspace; 1272 friend class Metadebug; 1273 1274 private: 1275 1276 // protects allocations 1277 Mutex* const _lock; 1278 1279 // Type of metadata allocated. 1280 const Metaspace::MetadataType _mdtype; 1281 1282 // Type of metaspace 1283 const Metaspace::MetaspaceType _space_type; 1284 1285 // List of chunks in use by this SpaceManager. Allocations 1286 // are done from the current chunk. The list is used for deallocating 1287 // chunks when the SpaceManager is freed. 1288 Metachunk* _chunks_in_use[NumberOfInUseLists]; 1289 Metachunk* _current_chunk; 1290 1291 // Maximum number of small chunks to allocate to a SpaceManager 1292 static uint const _small_chunk_limit; 1293 1294 // Maximum number of specialize chunks to allocate for anonymous and delegating 1295 // metadata space to a SpaceManager 1296 static uint const _anon_and_delegating_metadata_specialize_chunk_limit; 1297 1298 // Some running counters, but lets keep their number small to not add to much to 1299 // the per-classloader footprint. 1300 // Note: capacity = used + free + waste + overhead. We do not keep running counters for 1301 // free and waste. Their sum can be deduced from the three other values. 1302 size_t _overhead_words; 1303 size_t _capacity_words; 1304 size_t _used_words; 1305 1306 // Free lists of blocks are per SpaceManager since they 1307 // are assumed to be in chunks in use by the SpaceManager 1308 // and all chunks in use by a SpaceManager are freed when 1309 // the class loader using the SpaceManager is collected. 1310 BlockFreelist* _block_freelists; 1311 1312 private: 1313 // Accessors 1314 Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; } 1315 void set_chunks_in_use(ChunkIndex index, Metachunk* v) { 1316 _chunks_in_use[index] = v; 1317 } 1318 1319 BlockFreelist* block_freelists() const { return _block_freelists; } 1320 1321 Metaspace::MetadataType mdtype() { return _mdtype; } 1322 1323 VirtualSpaceList* vs_list() const { return Metaspace::get_space_list(_mdtype); } 1324 ChunkManager* chunk_manager() const { return Metaspace::get_chunk_manager(_mdtype); } 1325 1326 Metachunk* current_chunk() const { return _current_chunk; } 1327 void set_current_chunk(Metachunk* v) { 1328 _current_chunk = v; 1329 } 1330 1331 Metachunk* find_current_chunk(size_t word_size); 1332 1333 // Add chunk to the list of chunks in use 1334 void add_chunk(Metachunk* v, bool make_current); 1335 void retire_current_chunk(); 1336 1337 Mutex* lock() const { return _lock; } 1338 1339 // Adds to the given statistic object. Expects to be locked with lock(). 1340 void add_to_statistics_locked(SpaceManagerStatistics* out) const; 1341 1342 // Verify internal counters against the current state. Expects to be locked with lock(). 1343 DEBUG_ONLY(void verify_metrics_locked() const;) 1344 1345 protected: 1346 void initialize(); 1347 1348 public: 1349 SpaceManager(Metaspace::MetadataType mdtype, 1350 Metaspace::MetaspaceType space_type, 1351 Mutex* lock); 1352 ~SpaceManager(); 1353 1354 enum ChunkMultiples { 1355 MediumChunkMultiple = 4 1356 }; 1357 1358 static size_t specialized_chunk_size(bool is_class) { return is_class ? ClassSpecializedChunk : SpecializedChunk; } 1359 static size_t small_chunk_size(bool is_class) { return is_class ? ClassSmallChunk : SmallChunk; } 1360 static size_t medium_chunk_size(bool is_class) { return is_class ? ClassMediumChunk : MediumChunk; } 1361 1362 static size_t smallest_chunk_size(bool is_class) { return specialized_chunk_size(is_class); } 1363 1364 // Accessors 1365 bool is_class() const { return _mdtype == Metaspace::ClassType; } 1366 1367 size_t specialized_chunk_size() const { return specialized_chunk_size(is_class()); } 1368 size_t small_chunk_size() const { return small_chunk_size(is_class()); } 1369 size_t medium_chunk_size() const { return medium_chunk_size(is_class()); } 1370 1371 size_t smallest_chunk_size() const { return smallest_chunk_size(is_class()); } 1372 1373 size_t medium_chunk_bunch() const { return medium_chunk_size() * MediumChunkMultiple; } 1374 1375 bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); } 1376 1377 size_t capacity_words() const { return _capacity_words; } 1378 size_t used_words() const { return _used_words; } 1379 size_t overhead_words() const { return _overhead_words; } 1380 1381 // Adjust local, global counters after a new chunk has been added. 1382 void account_for_new_chunk(const Metachunk* new_chunk); 1383 1384 // Adjust local, global counters after space has been allocated from the current chunk. 1385 void account_for_allocation(size_t words); 1386 1387 // Adjust global counters just before the SpaceManager dies, after all its chunks 1388 // have been returned to the freelist. 1389 void account_for_spacemanager_death(); 1390 1391 // Adjust the initial chunk size to match one of the fixed chunk list sizes, 1392 // or return the unadjusted size if the requested size is humongous. 1393 static size_t adjust_initial_chunk_size(size_t requested, bool is_class_space); 1394 size_t adjust_initial_chunk_size(size_t requested) const; 1395 1396 // Get the initial chunks size for this metaspace type. 1397 size_t get_initial_chunk_size(Metaspace::MetaspaceType type) const; 1398 1399 // Todo: remove this once we have counters by chunk type. 1400 size_t sum_count_in_chunks_in_use(ChunkIndex i); 1401 1402 Metachunk* get_new_chunk(size_t chunk_word_size); 1403 1404 // Block allocation and deallocation. 1405 // Allocates a block from the current chunk 1406 MetaWord* allocate(size_t word_size); 1407 1408 // Helper for allocations 1409 MetaWord* allocate_work(size_t word_size); 1410 1411 // Returns a block to the per manager freelist 1412 void deallocate(MetaWord* p, size_t word_size); 1413 1414 // Based on the allocation size and a minimum chunk size, 1415 // returned chunk size (for expanding space for chunk allocation). 1416 size_t calc_chunk_size(size_t allocation_word_size); 1417 1418 // Called when an allocation from the current chunk fails. 1419 // Gets a new chunk (may require getting a new virtual space), 1420 // and allocates from that chunk. 1421 MetaWord* grow_and_allocate(size_t word_size); 1422 1423 // Notify memory usage to MemoryService. 1424 void track_metaspace_memory_usage(); 1425 1426 // debugging support. 1427 1428 void print_on(outputStream* st) const; 1429 void locked_print_chunks_in_use_on(outputStream* st) const; 1430 1431 void verify(); 1432 void verify_chunk_size(Metachunk* chunk); 1433 1434 // This adjusts the size given to be greater than the minimum allocation size in 1435 // words for data in metaspace. Esentially the minimum size is currently 3 words. 1436 size_t get_allocation_word_size(size_t word_size) { 1437 size_t byte_size = word_size * BytesPerWord; 1438 1439 size_t raw_bytes_size = MAX2(byte_size, sizeof(Metablock)); 1440 raw_bytes_size = align_up(raw_bytes_size, Metachunk::object_alignment()); 1441 1442 size_t raw_word_size = raw_bytes_size / BytesPerWord; 1443 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem"); 1444 1445 return raw_word_size; 1446 } 1447 1448 // Adds to the given statistic object. 1449 void add_to_statistics(SpaceManagerStatistics* out) const; 1450 1451 // Verify internal counters against the current state. 1452 DEBUG_ONLY(void verify_metrics() const;) 1453 1454 }; 1455 1456 uint const SpaceManager::_small_chunk_limit = 4; 1457 uint const SpaceManager::_anon_and_delegating_metadata_specialize_chunk_limit = 4; 1458 1459 void VirtualSpaceNode::inc_container_count() { 1460 assert_lock_strong(MetaspaceExpand_lock); 1461 _container_count++; 1462 } 1463 1464 void VirtualSpaceNode::dec_container_count() { 1465 assert_lock_strong(MetaspaceExpand_lock); 1466 _container_count--; 1467 } 1468 1469 #ifdef ASSERT 1470 void VirtualSpaceNode::verify_container_count() { 1471 assert(_container_count == container_count_slow(), 1472 "Inconsistency in container_count _container_count " UINTX_FORMAT 1473 " container_count_slow() " UINTX_FORMAT, _container_count, container_count_slow()); 1474 } 1475 #endif 1476 1477 // BlockFreelist methods 1478 1479 BlockFreelist::BlockFreelist() : _dictionary(new BlockTreeDictionary()), _small_blocks(NULL) {} 1480 1481 BlockFreelist::~BlockFreelist() { 1482 delete _dictionary; 1483 if (_small_blocks != NULL) { 1484 delete _small_blocks; 1485 } 1486 } 1487 1488 void BlockFreelist::return_block(MetaWord* p, size_t word_size) { 1489 assert(word_size >= SmallBlocks::small_block_min_size(), "never return dark matter"); 1490 1491 Metablock* free_chunk = ::new (p) Metablock(word_size); 1492 if (word_size < SmallBlocks::small_block_max_size()) { 1493 small_blocks()->return_block(free_chunk, word_size); 1494 } else { 1495 dictionary()->return_chunk(free_chunk); 1496 } 1497 log_trace(gc, metaspace, freelist, blocks)("returning block at " INTPTR_FORMAT " size = " 1498 SIZE_FORMAT, p2i(free_chunk), word_size); 1499 } 1500 1501 MetaWord* BlockFreelist::get_block(size_t word_size) { 1502 assert(word_size >= SmallBlocks::small_block_min_size(), "never get dark matter"); 1503 1504 // Try small_blocks first. 1505 if (word_size < SmallBlocks::small_block_max_size()) { 1506 // Don't create small_blocks() until needed. small_blocks() allocates the small block list for 1507 // this space manager. 1508 MetaWord* new_block = (MetaWord*) small_blocks()->get_block(word_size); 1509 if (new_block != NULL) { 1510 log_trace(gc, metaspace, freelist, blocks)("getting block at " INTPTR_FORMAT " size = " SIZE_FORMAT, 1511 p2i(new_block), word_size); 1512 return new_block; 1513 } 1514 } 1515 1516 if (word_size < BlockFreelist::min_dictionary_size()) { 1517 // If allocation in small blocks fails, this is Dark Matter. Too small for dictionary. 1518 return NULL; 1519 } 1520 1521 Metablock* free_block = dictionary()->get_chunk(word_size); 1522 if (free_block == NULL) { 1523 return NULL; 1524 } 1525 1526 const size_t block_size = free_block->size(); 1527 if (block_size > WasteMultiplier * word_size) { 1528 return_block((MetaWord*)free_block, block_size); 1529 return NULL; 1530 } 1531 1532 MetaWord* new_block = (MetaWord*)free_block; 1533 assert(block_size >= word_size, "Incorrect size of block from freelist"); 1534 const size_t unused = block_size - word_size; 1535 if (unused >= SmallBlocks::small_block_min_size()) { 1536 return_block(new_block + word_size, unused); 1537 } 1538 1539 log_trace(gc, metaspace, freelist, blocks)("getting block at " INTPTR_FORMAT " size = " SIZE_FORMAT, 1540 p2i(new_block), word_size); 1541 return new_block; 1542 } 1543 1544 void BlockFreelist::print_on(outputStream* st) const { 1545 dictionary()->print_free_lists(st); 1546 if (_small_blocks != NULL) { 1547 _small_blocks->print_on(st); 1548 } 1549 } 1550 1551 // VirtualSpaceNode methods 1552 1553 VirtualSpaceNode::~VirtualSpaceNode() { 1554 _rs.release(); 1555 if (_occupancy_map != NULL) { 1556 delete _occupancy_map; 1557 } 1558 #ifdef ASSERT 1559 size_t word_size = sizeof(*this) / BytesPerWord; 1560 Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1); 1561 #endif 1562 } 1563 1564 size_t VirtualSpaceNode::used_words_in_vs() const { 1565 return pointer_delta(top(), bottom(), sizeof(MetaWord)); 1566 } 1567 1568 // Space committed in the VirtualSpace 1569 size_t VirtualSpaceNode::capacity_words_in_vs() const { 1570 return pointer_delta(end(), bottom(), sizeof(MetaWord)); 1571 } 1572 1573 size_t VirtualSpaceNode::free_words_in_vs() const { 1574 return pointer_delta(end(), top(), sizeof(MetaWord)); 1575 } 1576 1577 // Given an address larger than top(), allocate padding chunks until top is at the given address. 1578 void VirtualSpaceNode::allocate_padding_chunks_until_top_is_at(MetaWord* target_top) { 1579 1580 assert(target_top > top(), "Sanity"); 1581 1582 // Padding chunks are added to the freelist. 1583 ChunkManager* const chunk_manager = Metaspace::get_chunk_manager(this->is_class()); 1584 1585 // shorthands 1586 const size_t spec_word_size = chunk_manager->specialized_chunk_word_size(); 1587 const size_t small_word_size = chunk_manager->small_chunk_word_size(); 1588 const size_t med_word_size = chunk_manager->medium_chunk_word_size(); 1589 1590 while (top() < target_top) { 1591 1592 // We could make this coding more generic, but right now we only deal with two possible chunk sizes 1593 // for padding chunks, so it is not worth it. 1594 size_t padding_chunk_word_size = small_word_size; 1595 if (is_aligned(top(), small_word_size * sizeof(MetaWord)) == false) { 1596 assert_is_aligned(top(), spec_word_size * sizeof(MetaWord)); // Should always hold true. 1597 padding_chunk_word_size = spec_word_size; 1598 } 1599 MetaWord* here = top(); 1600 assert_is_aligned(here, padding_chunk_word_size * sizeof(MetaWord)); 1601 inc_top(padding_chunk_word_size); 1602 1603 // Create new padding chunk. 1604 ChunkIndex padding_chunk_type = get_chunk_type_by_size(padding_chunk_word_size, is_class()); 1605 assert(padding_chunk_type == SpecializedIndex || padding_chunk_type == SmallIndex, "sanity"); 1606 1607 Metachunk* const padding_chunk = 1608 ::new (here) Metachunk(padding_chunk_type, is_class(), padding_chunk_word_size, this); 1609 assert(padding_chunk == (Metachunk*)here, "Sanity"); 1610 DEBUG_ONLY(padding_chunk->set_origin(origin_pad);) 1611 log_trace(gc, metaspace, freelist)("Created padding chunk in %s at " 1612 PTR_FORMAT ", size " SIZE_FORMAT_HEX ".", 1613 (is_class() ? "class space " : "metaspace"), 1614 p2i(padding_chunk), padding_chunk->word_size() * sizeof(MetaWord)); 1615 1616 // Mark chunk start in occupancy map. 1617 occupancy_map()->set_chunk_starts_at_address((MetaWord*)padding_chunk, true); 1618 1619 // Chunks are born as in-use (see MetaChunk ctor). So, before returning 1620 // the padding chunk to its chunk manager, mark it as in use (ChunkManager 1621 // will assert that). 1622 do_update_in_use_info_for_chunk(padding_chunk, true); 1623 1624 // Return Chunk to freelist. 1625 inc_container_count(); 1626 chunk_manager->return_single_chunk(padding_chunk_type, padding_chunk); 1627 // Please note: at this point, ChunkManager::return_single_chunk() 1628 // may already have merged the padding chunk with neighboring chunks, so 1629 // it may have vanished at this point. Do not reference the padding 1630 // chunk beyond this point. 1631 } 1632 1633 assert(top() == target_top, "Sanity"); 1634 1635 } // allocate_padding_chunks_until_top_is_at() 1636 1637 // Allocates the chunk from the virtual space only. 1638 // This interface is also used internally for debugging. Not all 1639 // chunks removed here are necessarily used for allocation. 1640 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) { 1641 // Non-humongous chunks are to be allocated aligned to their chunk 1642 // size. So, start addresses of medium chunks are aligned to medium 1643 // chunk size, those of small chunks to small chunk size and so 1644 // forth. This facilitates merging of free chunks and reduces 1645 // fragmentation. Chunk sizes are spec < small < medium, with each 1646 // larger chunk size being a multiple of the next smaller chunk 1647 // size. 1648 // Because of this alignment, me may need to create a number of padding 1649 // chunks. These chunks are created and added to the freelist. 1650 1651 // The chunk manager to which we will give our padding chunks. 1652 ChunkManager* const chunk_manager = Metaspace::get_chunk_manager(this->is_class()); 1653 1654 // shorthands 1655 const size_t spec_word_size = chunk_manager->specialized_chunk_word_size(); 1656 const size_t small_word_size = chunk_manager->small_chunk_word_size(); 1657 const size_t med_word_size = chunk_manager->medium_chunk_word_size(); 1658 1659 assert(chunk_word_size == spec_word_size || chunk_word_size == small_word_size || 1660 chunk_word_size >= med_word_size, "Invalid chunk size requested."); 1661 1662 // Chunk alignment (in bytes) == chunk size unless humongous. 1663 // Humongous chunks are aligned to the smallest chunk size (spec). 1664 const size_t required_chunk_alignment = (chunk_word_size > med_word_size ? 1665 spec_word_size : chunk_word_size) * sizeof(MetaWord); 1666 1667 // Do we have enough space to create the requested chunk plus 1668 // any padding chunks needed? 1669 MetaWord* const next_aligned = 1670 static_cast<MetaWord*>(align_up(top(), required_chunk_alignment)); 1671 if (!is_available((next_aligned - top()) + chunk_word_size)) { 1672 return NULL; 1673 } 1674 1675 // Before allocating the requested chunk, allocate padding chunks if necessary. 1676 // We only need to do this for small or medium chunks: specialized chunks are the 1677 // smallest size, hence always aligned. Homungous chunks are allocated unaligned 1678 // (implicitly, also aligned to smallest chunk size). 1679 if ((chunk_word_size == med_word_size || chunk_word_size == small_word_size) && next_aligned > top()) { 1680 log_trace(gc, metaspace, freelist)("Creating padding chunks in %s between %p and %p...", 1681 (is_class() ? "class space " : "metaspace"), 1682 top(), next_aligned); 1683 allocate_padding_chunks_until_top_is_at(next_aligned); 1684 // Now, top should be aligned correctly. 1685 assert_is_aligned(top(), required_chunk_alignment); 1686 } 1687 1688 // Now, top should be aligned correctly. 1689 assert_is_aligned(top(), required_chunk_alignment); 1690 1691 // Bottom of the new chunk 1692 MetaWord* chunk_limit = top(); 1693 assert(chunk_limit != NULL, "Not safe to call this method"); 1694 1695 // The virtual spaces are always expanded by the 1696 // commit granularity to enforce the following condition. 1697 // Without this the is_available check will not work correctly. 1698 assert(_virtual_space.committed_size() == _virtual_space.actual_committed_size(), 1699 "The committed memory doesn't match the expanded memory."); 1700 1701 if (!is_available(chunk_word_size)) { 1702 LogTarget(Debug, gc, metaspace, freelist) lt; 1703 if (lt.is_enabled()) { 1704 LogStream ls(lt); 1705 ls.print("VirtualSpaceNode::take_from_committed() not available " SIZE_FORMAT " words ", chunk_word_size); 1706 // Dump some information about the virtual space that is nearly full 1707 print_on(&ls); 1708 ls.cr(); // ~LogStream does not autoflush. 1709 } 1710 return NULL; 1711 } 1712 1713 // Take the space (bump top on the current virtual space). 1714 inc_top(chunk_word_size); 1715 1716 // Initialize the chunk 1717 ChunkIndex chunk_type = get_chunk_type_by_size(chunk_word_size, is_class()); 1718 Metachunk* result = ::new (chunk_limit) Metachunk(chunk_type, is_class(), chunk_word_size, this); 1719 assert(result == (Metachunk*)chunk_limit, "Sanity"); 1720 occupancy_map()->set_chunk_starts_at_address((MetaWord*)result, true); 1721 do_update_in_use_info_for_chunk(result, true); 1722 1723 inc_container_count(); 1724 1725 if (VerifyMetaspace) { 1726 DEBUG_ONLY(chunk_manager->locked_verify()); 1727 DEBUG_ONLY(this->verify()); 1728 } 1729 1730 DEBUG_ONLY(do_verify_chunk(result)); 1731 1732 result->inc_use_count(); 1733 1734 return result; 1735 } 1736 1737 1738 // Expand the virtual space (commit more of the reserved space) 1739 bool VirtualSpaceNode::expand_by(size_t min_words, size_t preferred_words) { 1740 size_t min_bytes = min_words * BytesPerWord; 1741 size_t preferred_bytes = preferred_words * BytesPerWord; 1742 1743 size_t uncommitted = virtual_space()->reserved_size() - virtual_space()->actual_committed_size(); 1744 1745 if (uncommitted < min_bytes) { 1746 return false; 1747 } 1748 1749 size_t commit = MIN2(preferred_bytes, uncommitted); 1750 bool result = virtual_space()->expand_by(commit, false); 1751 1752 if (result) { 1753 log_trace(gc, metaspace, freelist)("Expanded %s virtual space list node by " SIZE_FORMAT " words.", 1754 (is_class() ? "class" : "non-class"), commit); 1755 DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_committed_space_expanded)); 1756 } else { 1757 log_trace(gc, metaspace, freelist)("Failed to expand %s virtual space list node by " SIZE_FORMAT " words.", 1758 (is_class() ? "class" : "non-class"), commit); 1759 } 1760 1761 assert(result, "Failed to commit memory"); 1762 1763 return result; 1764 } 1765 1766 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) { 1767 assert_lock_strong(MetaspaceExpand_lock); 1768 Metachunk* result = take_from_committed(chunk_word_size); 1769 return result; 1770 } 1771 1772 bool VirtualSpaceNode::initialize() { 1773 1774 if (!_rs.is_reserved()) { 1775 return false; 1776 } 1777 1778 // These are necessary restriction to make sure that the virtual space always 1779 // grows in steps of Metaspace::commit_alignment(). If both base and size are 1780 // aligned only the middle alignment of the VirtualSpace is used. 1781 assert_is_aligned(_rs.base(), Metaspace::commit_alignment()); 1782 assert_is_aligned(_rs.size(), Metaspace::commit_alignment()); 1783 1784 // ReservedSpaces marked as special will have the entire memory 1785 // pre-committed. Setting a committed size will make sure that 1786 // committed_size and actual_committed_size agrees. 1787 size_t pre_committed_size = _rs.special() ? _rs.size() : 0; 1788 1789 bool result = virtual_space()->initialize_with_granularity(_rs, pre_committed_size, 1790 Metaspace::commit_alignment()); 1791 if (result) { 1792 assert(virtual_space()->committed_size() == virtual_space()->actual_committed_size(), 1793 "Checking that the pre-committed memory was registered by the VirtualSpace"); 1794 1795 set_top((MetaWord*)virtual_space()->low()); 1796 set_reserved(MemRegion((HeapWord*)_rs.base(), 1797 (HeapWord*)(_rs.base() + _rs.size()))); 1798 1799 assert(reserved()->start() == (HeapWord*) _rs.base(), 1800 "Reserved start was not set properly " PTR_FORMAT 1801 " != " PTR_FORMAT, p2i(reserved()->start()), p2i(_rs.base())); 1802 assert(reserved()->word_size() == _rs.size() / BytesPerWord, 1803 "Reserved size was not set properly " SIZE_FORMAT 1804 " != " SIZE_FORMAT, reserved()->word_size(), 1805 _rs.size() / BytesPerWord); 1806 } 1807 1808 // Initialize Occupancy Map. 1809 const size_t smallest_chunk_size = is_class() ? ClassSpecializedChunk : SpecializedChunk; 1810 _occupancy_map = new OccupancyMap(bottom(), reserved_words(), smallest_chunk_size); 1811 1812 return result; 1813 } 1814 1815 void VirtualSpaceNode::print_on(outputStream* st, size_t scale) const { 1816 size_t used_words = used_words_in_vs(); 1817 size_t commit_words = committed_words(); 1818 size_t res_words = reserved_words(); 1819 VirtualSpace* vs = virtual_space(); 1820 1821 st->print("node @" PTR_FORMAT ": ", p2i(this)); 1822 st->print("reserved="); 1823 print_scaled_words(st, res_words, scale); 1824 st->print(", committed="); 1825 print_scaled_words_and_percentage(st, commit_words, res_words, scale); 1826 st->print(", used="); 1827 print_scaled_words_and_percentage(st, used_words, res_words, scale); 1828 st->cr(); 1829 st->print(" [" PTR_FORMAT ", " PTR_FORMAT ", " 1830 PTR_FORMAT ", " PTR_FORMAT ")", 1831 p2i(bottom()), p2i(top()), p2i(end()), 1832 p2i(vs->high_boundary())); 1833 } 1834 1835 #ifdef ASSERT 1836 void VirtualSpaceNode::mangle() { 1837 size_t word_size = capacity_words_in_vs(); 1838 Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1); 1839 } 1840 #endif // ASSERT 1841 1842 // VirtualSpaceList methods 1843 // Space allocated from the VirtualSpace 1844 1845 VirtualSpaceList::~VirtualSpaceList() { 1846 VirtualSpaceListIterator iter(virtual_space_list()); 1847 while (iter.repeat()) { 1848 VirtualSpaceNode* vsl = iter.get_next(); 1849 delete vsl; 1850 } 1851 } 1852 1853 void VirtualSpaceList::inc_reserved_words(size_t v) { 1854 assert_lock_strong(MetaspaceExpand_lock); 1855 _reserved_words = _reserved_words + v; 1856 } 1857 void VirtualSpaceList::dec_reserved_words(size_t v) { 1858 assert_lock_strong(MetaspaceExpand_lock); 1859 _reserved_words = _reserved_words - v; 1860 } 1861 1862 #define assert_committed_below_limit() \ 1863 assert(MetaspaceUtils::committed_bytes() <= MaxMetaspaceSize, \ 1864 "Too much committed memory. Committed: " SIZE_FORMAT \ 1865 " limit (MaxMetaspaceSize): " SIZE_FORMAT, \ 1866 MetaspaceUtils::committed_bytes(), MaxMetaspaceSize); 1867 1868 void VirtualSpaceList::inc_committed_words(size_t v) { 1869 assert_lock_strong(MetaspaceExpand_lock); 1870 _committed_words = _committed_words + v; 1871 1872 assert_committed_below_limit(); 1873 } 1874 void VirtualSpaceList::dec_committed_words(size_t v) { 1875 assert_lock_strong(MetaspaceExpand_lock); 1876 _committed_words = _committed_words - v; 1877 1878 assert_committed_below_limit(); 1879 } 1880 1881 void VirtualSpaceList::inc_virtual_space_count() { 1882 assert_lock_strong(MetaspaceExpand_lock); 1883 _virtual_space_count++; 1884 } 1885 void VirtualSpaceList::dec_virtual_space_count() { 1886 assert_lock_strong(MetaspaceExpand_lock); 1887 _virtual_space_count--; 1888 } 1889 1890 void ChunkManager::remove_chunk(Metachunk* chunk) { 1891 size_t word_size = chunk->word_size(); 1892 ChunkIndex index = list_index(word_size); 1893 if (index != HumongousIndex) { 1894 free_chunks(index)->remove_chunk(chunk); 1895 } else { 1896 humongous_dictionary()->remove_chunk(chunk); 1897 } 1898 1899 // Chunk has been removed from the chunks free list, update counters. 1900 account_for_removed_chunk(chunk); 1901 } 1902 1903 bool ChunkManager::attempt_to_coalesce_around_chunk(Metachunk* chunk, ChunkIndex target_chunk_type) { 1904 assert_lock_strong(MetaspaceExpand_lock); 1905 assert(chunk != NULL, "invalid chunk pointer"); 1906 // Check for valid merge combinations. 1907 assert((chunk->get_chunk_type() == SpecializedIndex && 1908 (target_chunk_type == SmallIndex || target_chunk_type == MediumIndex)) || 1909 (chunk->get_chunk_type() == SmallIndex && target_chunk_type == MediumIndex), 1910 "Invalid chunk merge combination."); 1911 1912 const size_t target_chunk_word_size = 1913 get_size_for_nonhumongous_chunktype(target_chunk_type, this->is_class()); 1914 1915 // [ prospective merge region ) 1916 MetaWord* const p_merge_region_start = 1917 (MetaWord*) align_down(chunk, target_chunk_word_size * sizeof(MetaWord)); 1918 MetaWord* const p_merge_region_end = 1919 p_merge_region_start + target_chunk_word_size; 1920 1921 // We need the VirtualSpaceNode containing this chunk and its occupancy map. 1922 VirtualSpaceNode* const vsn = chunk->container(); 1923 OccupancyMap* const ocmap = vsn->occupancy_map(); 1924 1925 // The prospective chunk merge range must be completely contained by the 1926 // committed range of the virtual space node. 1927 if (p_merge_region_start < vsn->bottom() || p_merge_region_end > vsn->top()) { 1928 return false; 1929 } 1930 1931 // Only attempt to merge this range if at its start a chunk starts and at its end 1932 // a chunk ends. If a chunk (can only be humongous) straddles either start or end 1933 // of that range, we cannot merge. 1934 if (!ocmap->chunk_starts_at_address(p_merge_region_start)) { 1935 return false; 1936 } 1937 if (p_merge_region_end < vsn->top() && 1938 !ocmap->chunk_starts_at_address(p_merge_region_end)) { 1939 return false; 1940 } 1941 1942 // Now check if the prospective merge area contains live chunks. If it does we cannot merge. 1943 if (ocmap->is_region_in_use(p_merge_region_start, target_chunk_word_size)) { 1944 return false; 1945 } 1946 1947 // Success! Remove all chunks in this region... 1948 log_trace(gc, metaspace, freelist)("%s: coalescing chunks in area [%p-%p)...", 1949 (is_class() ? "class space" : "metaspace"), 1950 p_merge_region_start, p_merge_region_end); 1951 1952 const int num_chunks_removed = 1953 remove_chunks_in_area(p_merge_region_start, target_chunk_word_size); 1954 1955 // ... and create a single new bigger chunk. 1956 Metachunk* const p_new_chunk = 1957 ::new (p_merge_region_start) Metachunk(target_chunk_type, is_class(), target_chunk_word_size, vsn); 1958 assert(p_new_chunk == (Metachunk*)p_merge_region_start, "Sanity"); 1959 p_new_chunk->set_origin(origin_merge); 1960 1961 log_trace(gc, metaspace, freelist)("%s: created coalesced chunk at %p, size " SIZE_FORMAT_HEX ".", 1962 (is_class() ? "class space" : "metaspace"), 1963 p_new_chunk, p_new_chunk->word_size() * sizeof(MetaWord)); 1964 1965 // Fix occupancy map: remove old start bits of the small chunks and set new start bit. 1966 ocmap->wipe_chunk_start_bits_in_region(p_merge_region_start, target_chunk_word_size); 1967 ocmap->set_chunk_starts_at_address(p_merge_region_start, true); 1968 1969 // Mark chunk as free. Note: it is not necessary to update the occupancy 1970 // map in-use map, because the old chunks were also free, so nothing 1971 // should have changed. 1972 p_new_chunk->set_is_tagged_free(true); 1973 1974 // Add new chunk to its freelist. 1975 ChunkList* const list = free_chunks(target_chunk_type); 1976 list->return_chunk_at_head(p_new_chunk); 1977 1978 // And adjust ChunkManager:: _free_chunks_count (_free_chunks_total 1979 // should not have changed, because the size of the space should be the same) 1980 _free_chunks_count -= num_chunks_removed; 1981 _free_chunks_count ++; 1982 1983 // VirtualSpaceNode::container_count does not have to be modified: 1984 // it means "number of active (non-free) chunks", so merging free chunks 1985 // should not affect that count. 1986 1987 // At the end of a chunk merge, run verification tests. 1988 if (VerifyMetaspace) { 1989 DEBUG_ONLY(this->locked_verify()); 1990 DEBUG_ONLY(vsn->verify()); 1991 } 1992 1993 return true; 1994 } 1995 1996 // Remove all chunks in the given area - the chunks are supposed to be free - 1997 // from their corresponding freelists. Mark them as invalid. 1998 // - This does not correct the occupancy map. 1999 // - This does not adjust the counters in ChunkManager. 2000 // - Does not adjust container count counter in containing VirtualSpaceNode 2001 // Returns number of chunks removed. 2002 int ChunkManager::remove_chunks_in_area(MetaWord* p, size_t word_size) { 2003 assert(p != NULL && word_size > 0, "Invalid range."); 2004 const size_t smallest_chunk_size = get_size_for_nonhumongous_chunktype(SpecializedIndex, is_class()); 2005 assert_is_aligned(word_size, smallest_chunk_size); 2006 2007 Metachunk* const start = (Metachunk*) p; 2008 const Metachunk* const end = (Metachunk*)(p + word_size); 2009 Metachunk* cur = start; 2010 int num_removed = 0; 2011 while (cur < end) { 2012 Metachunk* next = (Metachunk*)(((MetaWord*)cur) + cur->word_size()); 2013 DEBUG_ONLY(do_verify_chunk(cur)); 2014 assert(cur->get_chunk_type() != HumongousIndex, "Unexpected humongous chunk found at %p.", cur); 2015 assert(cur->is_tagged_free(), "Chunk expected to be free (%p)", cur); 2016 log_trace(gc, metaspace, freelist)("%s: removing chunk %p, size " SIZE_FORMAT_HEX ".", 2017 (is_class() ? "class space" : "metaspace"), 2018 cur, cur->word_size() * sizeof(MetaWord)); 2019 cur->remove_sentinel(); 2020 // Note: cannot call ChunkManager::remove_chunk, because that 2021 // modifies the counters in ChunkManager, which we do not want. So 2022 // we call remove_chunk on the freelist directly (see also the 2023 // splitting function which does the same). 2024 ChunkList* const list = free_chunks(list_index(cur->word_size())); 2025 list->remove_chunk(cur); 2026 num_removed ++; 2027 cur = next; 2028 } 2029 return num_removed; 2030 } 2031 2032 // Walk the list of VirtualSpaceNodes and delete 2033 // nodes with a 0 container_count. Remove Metachunks in 2034 // the node from their respective freelists. 2035 void VirtualSpaceList::purge(ChunkManager* chunk_manager) { 2036 assert(SafepointSynchronize::is_at_safepoint(), "must be called at safepoint for contains to work"); 2037 assert_lock_strong(MetaspaceExpand_lock); 2038 // Don't use a VirtualSpaceListIterator because this 2039 // list is being changed and a straightforward use of an iterator is not safe. 2040 VirtualSpaceNode* purged_vsl = NULL; 2041 VirtualSpaceNode* prev_vsl = virtual_space_list(); 2042 VirtualSpaceNode* next_vsl = prev_vsl; 2043 while (next_vsl != NULL) { 2044 VirtualSpaceNode* vsl = next_vsl; 2045 DEBUG_ONLY(vsl->verify_container_count();) 2046 next_vsl = vsl->next(); 2047 // Don't free the current virtual space since it will likely 2048 // be needed soon. 2049 if (vsl->container_count() == 0 && vsl != current_virtual_space()) { 2050 log_trace(gc, metaspace, freelist)("Purging VirtualSpaceNode " PTR_FORMAT " (capacity: " SIZE_FORMAT 2051 ", used: " SIZE_FORMAT ").", p2i(vsl), vsl->capacity_words_in_vs(), vsl->used_words_in_vs()); 2052 DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_vsnodes_purged)); 2053 // Unlink it from the list 2054 if (prev_vsl == vsl) { 2055 // This is the case of the current node being the first node. 2056 assert(vsl == virtual_space_list(), "Expected to be the first node"); 2057 set_virtual_space_list(vsl->next()); 2058 } else { 2059 prev_vsl->set_next(vsl->next()); 2060 } 2061 2062 vsl->purge(chunk_manager); 2063 dec_reserved_words(vsl->reserved_words()); 2064 dec_committed_words(vsl->committed_words()); 2065 dec_virtual_space_count(); 2066 purged_vsl = vsl; 2067 delete vsl; 2068 } else { 2069 prev_vsl = vsl; 2070 } 2071 } 2072 #ifdef ASSERT 2073 if (purged_vsl != NULL) { 2074 // List should be stable enough to use an iterator here. 2075 VirtualSpaceListIterator iter(virtual_space_list()); 2076 while (iter.repeat()) { 2077 VirtualSpaceNode* vsl = iter.get_next(); 2078 assert(vsl != purged_vsl, "Purge of vsl failed"); 2079 } 2080 } 2081 #endif 2082 } 2083 2084 2085 // This function looks at the mmap regions in the metaspace without locking. 2086 // The chunks are added with store ordering and not deleted except for at 2087 // unloading time during a safepoint. 2088 bool VirtualSpaceList::contains(const void* ptr) { 2089 // List should be stable enough to use an iterator here because removing virtual 2090 // space nodes is only allowed at a safepoint. 2091 VirtualSpaceListIterator iter(virtual_space_list()); 2092 while (iter.repeat()) { 2093 VirtualSpaceNode* vsn = iter.get_next(); 2094 if (vsn->contains(ptr)) { 2095 return true; 2096 } 2097 } 2098 return false; 2099 } 2100 2101 void VirtualSpaceList::retire_current_virtual_space() { 2102 assert_lock_strong(MetaspaceExpand_lock); 2103 2104 VirtualSpaceNode* vsn = current_virtual_space(); 2105 2106 ChunkManager* cm = is_class() ? Metaspace::chunk_manager_class() : 2107 Metaspace::chunk_manager_metadata(); 2108 2109 vsn->retire(cm); 2110 } 2111 2112 void VirtualSpaceNode::retire(ChunkManager* chunk_manager) { 2113 DEBUG_ONLY(verify_container_count();) 2114 assert(this->is_class() == chunk_manager->is_class(), "Wrong ChunkManager?"); 2115 for (int i = (int)MediumIndex; i >= (int)ZeroIndex; --i) { 2116 ChunkIndex index = (ChunkIndex)i; 2117 size_t chunk_size = chunk_manager->size_by_index(index); 2118 2119 while (free_words_in_vs() >= chunk_size) { 2120 Metachunk* chunk = get_chunk_vs(chunk_size); 2121 // Chunk will be allocated aligned, so allocation may require 2122 // additional padding chunks. That may cause above allocation to 2123 // fail. Just ignore the failed allocation and continue with the 2124 // next smaller chunk size. As the VirtualSpaceNode comitted 2125 // size should be a multiple of the smallest chunk size, we 2126 // should always be able to fill the VirtualSpace completely. 2127 if (chunk == NULL) { 2128 break; 2129 } 2130 chunk_manager->return_single_chunk(index, chunk); 2131 } 2132 DEBUG_ONLY(verify_container_count();) 2133 } 2134 assert(free_words_in_vs() == 0, "should be empty now"); 2135 } 2136 2137 VirtualSpaceList::VirtualSpaceList(size_t word_size) : 2138 _is_class(false), 2139 _virtual_space_list(NULL), 2140 _current_virtual_space(NULL), 2141 _reserved_words(0), 2142 _committed_words(0), 2143 _virtual_space_count(0) { 2144 MutexLockerEx cl(MetaspaceExpand_lock, 2145 Mutex::_no_safepoint_check_flag); 2146 create_new_virtual_space(word_size); 2147 } 2148 2149 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) : 2150 _is_class(true), 2151 _virtual_space_list(NULL), 2152 _current_virtual_space(NULL), 2153 _reserved_words(0), 2154 _committed_words(0), 2155 _virtual_space_count(0) { 2156 MutexLockerEx cl(MetaspaceExpand_lock, 2157 Mutex::_no_safepoint_check_flag); 2158 VirtualSpaceNode* class_entry = new VirtualSpaceNode(is_class(), rs); 2159 bool succeeded = class_entry->initialize(); 2160 if (succeeded) { 2161 link_vs(class_entry); 2162 } 2163 } 2164 2165 size_t VirtualSpaceList::free_bytes() { 2166 return current_virtual_space()->free_words_in_vs() * BytesPerWord; 2167 } 2168 2169 // Allocate another meta virtual space and add it to the list. 2170 bool VirtualSpaceList::create_new_virtual_space(size_t vs_word_size) { 2171 assert_lock_strong(MetaspaceExpand_lock); 2172 2173 if (is_class()) { 2174 assert(false, "We currently don't support more than one VirtualSpace for" 2175 " the compressed class space. The initialization of the" 2176 " CCS uses another code path and should not hit this path."); 2177 return false; 2178 } 2179 2180 if (vs_word_size == 0) { 2181 assert(false, "vs_word_size should always be at least _reserve_alignment large."); 2182 return false; 2183 } 2184 2185 // Reserve the space 2186 size_t vs_byte_size = vs_word_size * BytesPerWord; 2187 assert_is_aligned(vs_byte_size, Metaspace::reserve_alignment()); 2188 2189 // Allocate the meta virtual space and initialize it. 2190 VirtualSpaceNode* new_entry = new VirtualSpaceNode(is_class(), vs_byte_size); 2191 if (!new_entry->initialize()) { 2192 delete new_entry; 2193 return false; 2194 } else { 2195 assert(new_entry->reserved_words() == vs_word_size, 2196 "Reserved memory size differs from requested memory size"); 2197 // ensure lock-free iteration sees fully initialized node 2198 OrderAccess::storestore(); 2199 link_vs(new_entry); 2200 DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_vsnodes_created)); 2201 return true; 2202 } 2203 } 2204 2205 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry) { 2206 if (virtual_space_list() == NULL) { 2207 set_virtual_space_list(new_entry); 2208 } else { 2209 current_virtual_space()->set_next(new_entry); 2210 } 2211 set_current_virtual_space(new_entry); 2212 inc_reserved_words(new_entry->reserved_words()); 2213 inc_committed_words(new_entry->committed_words()); 2214 inc_virtual_space_count(); 2215 #ifdef ASSERT 2216 new_entry->mangle(); 2217 #endif 2218 LogTarget(Trace, gc, metaspace) lt; 2219 if (lt.is_enabled()) { 2220 LogStream ls(lt); 2221 VirtualSpaceNode* vsl = current_virtual_space(); 2222 ResourceMark rm; 2223 vsl->print_on(&ls); 2224 ls.cr(); // ~LogStream does not autoflush. 2225 } 2226 } 2227 2228 bool VirtualSpaceList::expand_node_by(VirtualSpaceNode* node, 2229 size_t min_words, 2230 size_t preferred_words) { 2231 size_t before = node->committed_words(); 2232 2233 bool result = node->expand_by(min_words, preferred_words); 2234 2235 size_t after = node->committed_words(); 2236 2237 // after and before can be the same if the memory was pre-committed. 2238 assert(after >= before, "Inconsistency"); 2239 inc_committed_words(after - before); 2240 2241 return result; 2242 } 2243 2244 bool VirtualSpaceList::expand_by(size_t min_words, size_t preferred_words) { 2245 assert_is_aligned(min_words, Metaspace::commit_alignment_words()); 2246 assert_is_aligned(preferred_words, Metaspace::commit_alignment_words()); 2247 assert(min_words <= preferred_words, "Invalid arguments"); 2248 2249 const char* const class_or_not = (is_class() ? "class" : "non-class"); 2250 2251 if (!MetaspaceGC::can_expand(min_words, this->is_class())) { 2252 log_trace(gc, metaspace, freelist)("Cannot expand %s virtual space list.", 2253 class_or_not); 2254 return false; 2255 } 2256 2257 size_t allowed_expansion_words = MetaspaceGC::allowed_expansion(); 2258 if (allowed_expansion_words < min_words) { 2259 log_trace(gc, metaspace, freelist)("Cannot expand %s virtual space list (must try gc first).", 2260 class_or_not); 2261 return false; 2262 } 2263 2264 size_t max_expansion_words = MIN2(preferred_words, allowed_expansion_words); 2265 2266 // Commit more memory from the the current virtual space. 2267 bool vs_expanded = expand_node_by(current_virtual_space(), 2268 min_words, 2269 max_expansion_words); 2270 if (vs_expanded) { 2271 log_trace(gc, metaspace, freelist)("Expanded %s virtual space list.", 2272 class_or_not); 2273 return true; 2274 } 2275 log_trace(gc, metaspace, freelist)("%s virtual space list: retire current node.", 2276 class_or_not); 2277 retire_current_virtual_space(); 2278 2279 // Get another virtual space. 2280 size_t grow_vs_words = MAX2((size_t)VirtualSpaceSize, preferred_words); 2281 grow_vs_words = align_up(grow_vs_words, Metaspace::reserve_alignment_words()); 2282 2283 if (create_new_virtual_space(grow_vs_words)) { 2284 if (current_virtual_space()->is_pre_committed()) { 2285 // The memory was pre-committed, so we are done here. 2286 assert(min_words <= current_virtual_space()->committed_words(), 2287 "The new VirtualSpace was pre-committed, so it" 2288 "should be large enough to fit the alloc request."); 2289 return true; 2290 } 2291 2292 return expand_node_by(current_virtual_space(), 2293 min_words, 2294 max_expansion_words); 2295 } 2296 2297 return false; 2298 } 2299 2300 // Given a chunk, calculate the largest possible padding space which 2301 // could be required when allocating it. 2302 static size_t largest_possible_padding_size_for_chunk(size_t chunk_word_size, bool is_class) { 2303 const ChunkIndex chunk_type = get_chunk_type_by_size(chunk_word_size, is_class); 2304 if (chunk_type != HumongousIndex) { 2305 // Normal, non-humongous chunks are allocated at chunk size 2306 // boundaries, so the largest padding space required would be that 2307 // minus the smallest chunk size. 2308 const size_t smallest_chunk_size = is_class ? ClassSpecializedChunk : SpecializedChunk; 2309 return chunk_word_size - smallest_chunk_size; 2310 } else { 2311 // Humongous chunks are allocated at smallest-chunksize 2312 // boundaries, so there is no padding required. 2313 return 0; 2314 } 2315 } 2316 2317 2318 Metachunk* VirtualSpaceList::get_new_chunk(size_t chunk_word_size, size_t suggested_commit_granularity) { 2319 2320 // Allocate a chunk out of the current virtual space. 2321 Metachunk* next = current_virtual_space()->get_chunk_vs(chunk_word_size); 2322 2323 if (next != NULL) { 2324 return next; 2325 } 2326 2327 // The expand amount is currently only determined by the requested sizes 2328 // and not how much committed memory is left in the current virtual space. 2329 2330 // We must have enough space for the requested size and any 2331 // additional reqired padding chunks. 2332 const size_t size_for_padding = largest_possible_padding_size_for_chunk(chunk_word_size, this->is_class()); 2333 2334 size_t min_word_size = align_up(chunk_word_size + size_for_padding, Metaspace::commit_alignment_words()); 2335 size_t preferred_word_size = align_up(suggested_commit_granularity, Metaspace::commit_alignment_words()); 2336 if (min_word_size >= preferred_word_size) { 2337 // Can happen when humongous chunks are allocated. 2338 preferred_word_size = min_word_size; 2339 } 2340 2341 bool expanded = expand_by(min_word_size, preferred_word_size); 2342 if (expanded) { 2343 next = current_virtual_space()->get_chunk_vs(chunk_word_size); 2344 assert(next != NULL, "The allocation was expected to succeed after the expansion"); 2345 } 2346 2347 return next; 2348 } 2349 2350 void VirtualSpaceList::print_on(outputStream* st, size_t scale) const { 2351 st->print_cr(SIZE_FORMAT " nodes, current node: " PTR_FORMAT, 2352 _virtual_space_count, p2i(_current_virtual_space)); 2353 VirtualSpaceListIterator iter(virtual_space_list()); 2354 while (iter.repeat()) { 2355 st->cr(); 2356 VirtualSpaceNode* node = iter.get_next(); 2357 node->print_on(st, scale); 2358 } 2359 } 2360 2361 void VirtualSpaceList::print_map(outputStream* st) const { 2362 VirtualSpaceNode* list = virtual_space_list(); 2363 VirtualSpaceListIterator iter(list); 2364 unsigned i = 0; 2365 while (iter.repeat()) { 2366 st->print_cr("Node %u:", i); 2367 VirtualSpaceNode* node = iter.get_next(); 2368 node->print_map(st, this->is_class()); 2369 i ++; 2370 } 2371 } 2372 2373 // MetaspaceGC methods 2374 2375 // VM_CollectForMetadataAllocation is the vm operation used to GC. 2376 // Within the VM operation after the GC the attempt to allocate the metadata 2377 // should succeed. If the GC did not free enough space for the metaspace 2378 // allocation, the HWM is increased so that another virtualspace will be 2379 // allocated for the metadata. With perm gen the increase in the perm 2380 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The 2381 // metaspace policy uses those as the small and large steps for the HWM. 2382 // 2383 // After the GC the compute_new_size() for MetaspaceGC is called to 2384 // resize the capacity of the metaspaces. The current implementation 2385 // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used 2386 // to resize the Java heap by some GC's. New flags can be implemented 2387 // if really needed. MinMetaspaceFreeRatio is used to calculate how much 2388 // free space is desirable in the metaspace capacity to decide how much 2389 // to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much 2390 // free space is desirable in the metaspace capacity before decreasing 2391 // the HWM. 2392 2393 // Calculate the amount to increase the high water mark (HWM). 2394 // Increase by a minimum amount (MinMetaspaceExpansion) so that 2395 // another expansion is not requested too soon. If that is not 2396 // enough to satisfy the allocation, increase by MaxMetaspaceExpansion. 2397 // If that is still not enough, expand by the size of the allocation 2398 // plus some. 2399 size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) { 2400 size_t min_delta = MinMetaspaceExpansion; 2401 size_t max_delta = MaxMetaspaceExpansion; 2402 size_t delta = align_up(bytes, Metaspace::commit_alignment()); 2403 2404 if (delta <= min_delta) { 2405 delta = min_delta; 2406 } else if (delta <= max_delta) { 2407 // Don't want to hit the high water mark on the next 2408 // allocation so make the delta greater than just enough 2409 // for this allocation. 2410 delta = max_delta; 2411 } else { 2412 // This allocation is large but the next ones are probably not 2413 // so increase by the minimum. 2414 delta = delta + min_delta; 2415 } 2416 2417 assert_is_aligned(delta, Metaspace::commit_alignment()); 2418 2419 return delta; 2420 } 2421 2422 size_t MetaspaceGC::capacity_until_GC() { 2423 size_t value = OrderAccess::load_acquire(&_capacity_until_GC); 2424 assert(value >= MetaspaceSize, "Not initialized properly?"); 2425 return value; 2426 } 2427 2428 bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC) { 2429 assert_is_aligned(v, Metaspace::commit_alignment()); 2430 2431 intptr_t capacity_until_GC = _capacity_until_GC; 2432 intptr_t new_value = capacity_until_GC + v; 2433 2434 if (new_value < capacity_until_GC) { 2435 // The addition wrapped around, set new_value to aligned max value. 2436 new_value = align_down(max_uintx, Metaspace::commit_alignment()); 2437 } 2438 2439 intptr_t expected = _capacity_until_GC; 2440 intptr_t actual = Atomic::cmpxchg(new_value, &_capacity_until_GC, expected); 2441 2442 if (expected != actual) { 2443 return false; 2444 } 2445 2446 if (new_cap_until_GC != NULL) { 2447 *new_cap_until_GC = new_value; 2448 } 2449 if (old_cap_until_GC != NULL) { 2450 *old_cap_until_GC = capacity_until_GC; 2451 } 2452 return true; 2453 } 2454 2455 size_t MetaspaceGC::dec_capacity_until_GC(size_t v) { 2456 assert_is_aligned(v, Metaspace::commit_alignment()); 2457 2458 return (size_t)Atomic::sub((intptr_t)v, &_capacity_until_GC); 2459 } 2460 2461 void MetaspaceGC::initialize() { 2462 // Set the high-water mark to MaxMetapaceSize during VM initializaton since 2463 // we can't do a GC during initialization. 2464 _capacity_until_GC = MaxMetaspaceSize; 2465 } 2466 2467 void MetaspaceGC::post_initialize() { 2468 // Reset the high-water mark once the VM initialization is done. 2469 _capacity_until_GC = MAX2(MetaspaceUtils::committed_bytes(), MetaspaceSize); 2470 } 2471 2472 bool MetaspaceGC::can_expand(size_t word_size, bool is_class) { 2473 // Check if the compressed class space is full. 2474 if (is_class && Metaspace::using_class_space()) { 2475 size_t class_committed = MetaspaceUtils::committed_bytes(Metaspace::ClassType); 2476 if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) { 2477 log_trace(gc, metaspace, freelist)("Cannot expand %s metaspace by " SIZE_FORMAT " words (CompressedClassSpaceSize = " SIZE_FORMAT " words)", 2478 (is_class ? "class" : "non-class"), word_size, CompressedClassSpaceSize / sizeof(MetaWord)); 2479 return false; 2480 } 2481 } 2482 2483 // Check if the user has imposed a limit on the metaspace memory. 2484 size_t committed_bytes = MetaspaceUtils::committed_bytes(); 2485 if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) { 2486 log_trace(gc, metaspace, freelist)("Cannot expand %s metaspace by " SIZE_FORMAT " words (MaxMetaspaceSize = " SIZE_FORMAT " words)", 2487 (is_class ? "class" : "non-class"), word_size, MaxMetaspaceSize / sizeof(MetaWord)); 2488 return false; 2489 } 2490 2491 return true; 2492 } 2493 2494 size_t MetaspaceGC::allowed_expansion() { 2495 size_t committed_bytes = MetaspaceUtils::committed_bytes(); 2496 size_t capacity_until_gc = capacity_until_GC(); 2497 2498 assert(capacity_until_gc >= committed_bytes, 2499 "capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT, 2500 capacity_until_gc, committed_bytes); 2501 2502 size_t left_until_max = MaxMetaspaceSize - committed_bytes; 2503 size_t left_until_GC = capacity_until_gc - committed_bytes; 2504 size_t left_to_commit = MIN2(left_until_GC, left_until_max); 2505 log_trace(gc, metaspace, freelist)("allowed expansion words: " SIZE_FORMAT 2506 " (left_until_max: " SIZE_FORMAT ", left_until_GC: " SIZE_FORMAT ".", 2507 left_to_commit / BytesPerWord, left_until_max / BytesPerWord, left_until_GC / BytesPerWord); 2508 2509 return left_to_commit / BytesPerWord; 2510 } 2511 2512 void MetaspaceGC::compute_new_size() { 2513 assert(_shrink_factor <= 100, "invalid shrink factor"); 2514 uint current_shrink_factor = _shrink_factor; 2515 _shrink_factor = 0; 2516 2517 // Using committed_bytes() for used_after_gc is an overestimation, since the 2518 // chunk free lists are included in committed_bytes() and the memory in an 2519 // un-fragmented chunk free list is available for future allocations. 2520 // However, if the chunk free lists becomes fragmented, then the memory may 2521 // not be available for future allocations and the memory is therefore "in use". 2522 // Including the chunk free lists in the definition of "in use" is therefore 2523 // necessary. Not including the chunk free lists can cause capacity_until_GC to 2524 // shrink below committed_bytes() and this has caused serious bugs in the past. 2525 const size_t used_after_gc = MetaspaceUtils::committed_bytes(); 2526 const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC(); 2527 2528 const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0; 2529 const double maximum_used_percentage = 1.0 - minimum_free_percentage; 2530 2531 const double min_tmp = used_after_gc / maximum_used_percentage; 2532 size_t minimum_desired_capacity = 2533 (size_t)MIN2(min_tmp, double(max_uintx)); 2534 // Don't shrink less than the initial generation size 2535 minimum_desired_capacity = MAX2(minimum_desired_capacity, 2536 MetaspaceSize); 2537 2538 log_trace(gc, metaspace)("MetaspaceGC::compute_new_size: "); 2539 log_trace(gc, metaspace)(" minimum_free_percentage: %6.2f maximum_used_percentage: %6.2f", 2540 minimum_free_percentage, maximum_used_percentage); 2541 log_trace(gc, metaspace)(" used_after_gc : %6.1fKB", used_after_gc / (double) K); 2542 2543 2544 size_t shrink_bytes = 0; 2545 if (capacity_until_GC < minimum_desired_capacity) { 2546 // If we have less capacity below the metaspace HWM, then 2547 // increment the HWM. 2548 size_t expand_bytes = minimum_desired_capacity - capacity_until_GC; 2549 expand_bytes = align_up(expand_bytes, Metaspace::commit_alignment()); 2550 // Don't expand unless it's significant 2551 if (expand_bytes >= MinMetaspaceExpansion) { 2552 size_t new_capacity_until_GC = 0; 2553 bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC); 2554 assert(succeeded, "Should always succesfully increment HWM when at safepoint"); 2555 2556 Metaspace::tracer()->report_gc_threshold(capacity_until_GC, 2557 new_capacity_until_GC, 2558 MetaspaceGCThresholdUpdater::ComputeNewSize); 2559 log_trace(gc, metaspace)(" expanding: minimum_desired_capacity: %6.1fKB expand_bytes: %6.1fKB MinMetaspaceExpansion: %6.1fKB new metaspace HWM: %6.1fKB", 2560 minimum_desired_capacity / (double) K, 2561 expand_bytes / (double) K, 2562 MinMetaspaceExpansion / (double) K, 2563 new_capacity_until_GC / (double) K); 2564 } 2565 return; 2566 } 2567 2568 // No expansion, now see if we want to shrink 2569 // We would never want to shrink more than this 2570 assert(capacity_until_GC >= minimum_desired_capacity, 2571 SIZE_FORMAT " >= " SIZE_FORMAT, 2572 capacity_until_GC, minimum_desired_capacity); 2573 size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity; 2574 2575 // Should shrinking be considered? 2576 if (MaxMetaspaceFreeRatio < 100) { 2577 const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0; 2578 const double minimum_used_percentage = 1.0 - maximum_free_percentage; 2579 const double max_tmp = used_after_gc / minimum_used_percentage; 2580 size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx)); 2581 maximum_desired_capacity = MAX2(maximum_desired_capacity, 2582 MetaspaceSize); 2583 log_trace(gc, metaspace)(" maximum_free_percentage: %6.2f minimum_used_percentage: %6.2f", 2584 maximum_free_percentage, minimum_used_percentage); 2585 log_trace(gc, metaspace)(" minimum_desired_capacity: %6.1fKB maximum_desired_capacity: %6.1fKB", 2586 minimum_desired_capacity / (double) K, maximum_desired_capacity / (double) K); 2587 2588 assert(minimum_desired_capacity <= maximum_desired_capacity, 2589 "sanity check"); 2590 2591 if (capacity_until_GC > maximum_desired_capacity) { 2592 // Capacity too large, compute shrinking size 2593 shrink_bytes = capacity_until_GC - maximum_desired_capacity; 2594 // We don't want shrink all the way back to initSize if people call 2595 // System.gc(), because some programs do that between "phases" and then 2596 // we'd just have to grow the heap up again for the next phase. So we 2597 // damp the shrinking: 0% on the first call, 10% on the second call, 40% 2598 // on the third call, and 100% by the fourth call. But if we recompute 2599 // size without shrinking, it goes back to 0%. 2600 shrink_bytes = shrink_bytes / 100 * current_shrink_factor; 2601 2602 shrink_bytes = align_down(shrink_bytes, Metaspace::commit_alignment()); 2603 2604 assert(shrink_bytes <= max_shrink_bytes, 2605 "invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT, 2606 shrink_bytes, max_shrink_bytes); 2607 if (current_shrink_factor == 0) { 2608 _shrink_factor = 10; 2609 } else { 2610 _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100); 2611 } 2612 log_trace(gc, metaspace)(" shrinking: initThreshold: %.1fK maximum_desired_capacity: %.1fK", 2613 MetaspaceSize / (double) K, maximum_desired_capacity / (double) K); 2614 log_trace(gc, metaspace)(" shrink_bytes: %.1fK current_shrink_factor: %d new shrink factor: %d MinMetaspaceExpansion: %.1fK", 2615 shrink_bytes / (double) K, current_shrink_factor, _shrink_factor, MinMetaspaceExpansion / (double) K); 2616 } 2617 } 2618 2619 // Don't shrink unless it's significant 2620 if (shrink_bytes >= MinMetaspaceExpansion && 2621 ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) { 2622 size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes); 2623 Metaspace::tracer()->report_gc_threshold(capacity_until_GC, 2624 new_capacity_until_GC, 2625 MetaspaceGCThresholdUpdater::ComputeNewSize); 2626 } 2627 } 2628 2629 // Metadebug methods 2630 2631 void Metadebug::init_allocation_fail_alot_count() { 2632 if (MetadataAllocationFailALot) { 2633 _allocation_fail_alot_count = 2634 1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0)); 2635 } 2636 } 2637 2638 #ifdef ASSERT 2639 bool Metadebug::test_metadata_failure() { 2640 if (MetadataAllocationFailALot && 2641 Threads::is_vm_complete()) { 2642 if (_allocation_fail_alot_count > 0) { 2643 _allocation_fail_alot_count--; 2644 } else { 2645 log_trace(gc, metaspace, freelist)("Metadata allocation failing for MetadataAllocationFailALot"); 2646 init_allocation_fail_alot_count(); 2647 return true; 2648 } 2649 } 2650 return false; 2651 } 2652 #endif 2653 2654 // ChunkManager methods 2655 size_t ChunkManager::free_chunks_total_words() { 2656 return _free_chunks_total; 2657 } 2658 2659 size_t ChunkManager::free_chunks_total_bytes() { 2660 return free_chunks_total_words() * BytesPerWord; 2661 } 2662 2663 // Update internal accounting after a chunk was added 2664 void ChunkManager::account_for_added_chunk(const Metachunk* c) { 2665 assert_lock_strong(MetaspaceExpand_lock); 2666 _free_chunks_count ++; 2667 _free_chunks_total += c->word_size(); 2668 } 2669 2670 // Update internal accounting after a chunk was removed 2671 void ChunkManager::account_for_removed_chunk(const Metachunk* c) { 2672 assert_lock_strong(MetaspaceExpand_lock); 2673 assert(_free_chunks_count >= 1, 2674 "ChunkManager::_free_chunks_count: about to go negative (" SIZE_FORMAT ").", _free_chunks_count); 2675 assert(_free_chunks_total >= c->word_size(), 2676 "ChunkManager::_free_chunks_total: about to go negative" 2677 "(now: " SIZE_FORMAT ", decrement value: " SIZE_FORMAT ").", _free_chunks_total, c->word_size()); 2678 _free_chunks_count --; 2679 _free_chunks_total -= c->word_size(); 2680 } 2681 2682 size_t ChunkManager::free_chunks_count() { 2683 #ifdef ASSERT 2684 if (!UseConcMarkSweepGC && !MetaspaceExpand_lock->is_locked()) { 2685 MutexLockerEx cl(MetaspaceExpand_lock, 2686 Mutex::_no_safepoint_check_flag); 2687 // This lock is only needed in debug because the verification 2688 // of the _free_chunks_totals walks the list of free chunks 2689 slow_locked_verify_free_chunks_count(); 2690 } 2691 #endif 2692 return _free_chunks_count; 2693 } 2694 2695 ChunkIndex ChunkManager::list_index(size_t size) { 2696 return get_chunk_type_by_size(size, is_class()); 2697 } 2698 2699 size_t ChunkManager::size_by_index(ChunkIndex index) const { 2700 index_bounds_check(index); 2701 assert(index != HumongousIndex, "Do not call for humongous chunks."); 2702 return get_size_for_nonhumongous_chunktype(index, is_class()); 2703 } 2704 2705 void ChunkManager::locked_verify_free_chunks_total() { 2706 assert_lock_strong(MetaspaceExpand_lock); 2707 assert(sum_free_chunks() == _free_chunks_total, 2708 "_free_chunks_total " SIZE_FORMAT " is not the" 2709 " same as sum " SIZE_FORMAT, _free_chunks_total, 2710 sum_free_chunks()); 2711 } 2712 2713 void ChunkManager::verify_free_chunks_total() { 2714 MutexLockerEx cl(MetaspaceExpand_lock, 2715 Mutex::_no_safepoint_check_flag); 2716 locked_verify_free_chunks_total(); 2717 } 2718 2719 void ChunkManager::locked_verify_free_chunks_count() { 2720 assert_lock_strong(MetaspaceExpand_lock); 2721 assert(sum_free_chunks_count() == _free_chunks_count, 2722 "_free_chunks_count " SIZE_FORMAT " is not the" 2723 " same as sum " SIZE_FORMAT, _free_chunks_count, 2724 sum_free_chunks_count()); 2725 } 2726 2727 void ChunkManager::verify_free_chunks_count() { 2728 #ifdef ASSERT 2729 MutexLockerEx cl(MetaspaceExpand_lock, 2730 Mutex::_no_safepoint_check_flag); 2731 locked_verify_free_chunks_count(); 2732 #endif 2733 } 2734 2735 void ChunkManager::verify() { 2736 MutexLockerEx cl(MetaspaceExpand_lock, 2737 Mutex::_no_safepoint_check_flag); 2738 locked_verify(); 2739 } 2740 2741 void ChunkManager::locked_verify() { 2742 locked_verify_free_chunks_count(); 2743 locked_verify_free_chunks_total(); 2744 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 2745 ChunkList* list = free_chunks(i); 2746 if (list != NULL) { 2747 Metachunk* chunk = list->head(); 2748 while (chunk) { 2749 DEBUG_ONLY(do_verify_chunk(chunk);) 2750 assert(chunk->is_tagged_free(), "Chunk should be tagged as free."); 2751 chunk = chunk->next(); 2752 } 2753 } 2754 } 2755 } 2756 2757 void ChunkManager::locked_print_free_chunks(outputStream* st) { 2758 assert_lock_strong(MetaspaceExpand_lock); 2759 st->print_cr("Free chunk total " SIZE_FORMAT " count " SIZE_FORMAT, 2760 _free_chunks_total, _free_chunks_count); 2761 } 2762 2763 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) { 2764 assert_lock_strong(MetaspaceExpand_lock); 2765 st->print_cr("Sum free chunk total " SIZE_FORMAT " count " SIZE_FORMAT, 2766 sum_free_chunks(), sum_free_chunks_count()); 2767 } 2768 2769 ChunkList* ChunkManager::free_chunks(ChunkIndex index) { 2770 assert(index == SpecializedIndex || index == SmallIndex || index == MediumIndex, 2771 "Bad index: %d", (int)index); 2772 2773 return &_free_chunks[index]; 2774 } 2775 2776 // These methods that sum the free chunk lists are used in printing 2777 // methods that are used in product builds. 2778 size_t ChunkManager::sum_free_chunks() { 2779 assert_lock_strong(MetaspaceExpand_lock); 2780 size_t result = 0; 2781 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 2782 ChunkList* list = free_chunks(i); 2783 2784 if (list == NULL) { 2785 continue; 2786 } 2787 2788 result = result + list->count() * list->size(); 2789 } 2790 result = result + humongous_dictionary()->total_size(); 2791 return result; 2792 } 2793 2794 size_t ChunkManager::sum_free_chunks_count() { 2795 assert_lock_strong(MetaspaceExpand_lock); 2796 size_t count = 0; 2797 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 2798 ChunkList* list = free_chunks(i); 2799 if (list == NULL) { 2800 continue; 2801 } 2802 count = count + list->count(); 2803 } 2804 count = count + humongous_dictionary()->total_free_blocks(); 2805 return count; 2806 } 2807 2808 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) { 2809 ChunkIndex index = list_index(word_size); 2810 assert(index < HumongousIndex, "No humongous list"); 2811 return free_chunks(index); 2812 } 2813 2814 // Helper for chunk splitting: given a target chunk size and a larger free chunk, 2815 // split up the larger chunk into n smaller chunks, at least one of which should be 2816 // the target chunk of target chunk size. The smaller chunks, including the target 2817 // chunk, are returned to the freelist. The pointer to the target chunk is returned. 2818 // Note that this chunk is supposed to be removed from the freelist right away. 2819 Metachunk* ChunkManager::split_chunk(size_t target_chunk_word_size, Metachunk* larger_chunk) { 2820 assert(larger_chunk->word_size() > target_chunk_word_size, "Sanity"); 2821 2822 const ChunkIndex larger_chunk_index = larger_chunk->get_chunk_type(); 2823 const ChunkIndex target_chunk_index = get_chunk_type_by_size(target_chunk_word_size, is_class()); 2824 2825 MetaWord* const region_start = (MetaWord*)larger_chunk; 2826 const size_t region_word_len = larger_chunk->word_size(); 2827 MetaWord* const region_end = region_start + region_word_len; 2828 VirtualSpaceNode* const vsn = larger_chunk->container(); 2829 OccupancyMap* const ocmap = vsn->occupancy_map(); 2830 2831 // Any larger non-humongous chunk size is a multiple of any smaller chunk size. 2832 // Since non-humongous chunks are aligned to their chunk size, the larger chunk should start 2833 // at an address suitable to place the smaller target chunk. 2834 assert_is_aligned(region_start, target_chunk_word_size); 2835 2836 // Remove old chunk. 2837 free_chunks(larger_chunk_index)->remove_chunk(larger_chunk); 2838 larger_chunk->remove_sentinel(); 2839 2840 // Prevent access to the old chunk from here on. 2841 larger_chunk = NULL; 2842 // ... and wipe it. 2843 DEBUG_ONLY(memset(region_start, 0xfe, region_word_len * BytesPerWord)); 2844 2845 // In its place create first the target chunk... 2846 MetaWord* p = region_start; 2847 Metachunk* target_chunk = ::new (p) Metachunk(target_chunk_index, is_class(), target_chunk_word_size, vsn); 2848 assert(target_chunk == (Metachunk*)p, "Sanity"); 2849 target_chunk->set_origin(origin_split); 2850 2851 // Note: we do not need to mark its start in the occupancy map 2852 // because it coincides with the old chunk start. 2853 2854 // Mark chunk as free and return to the freelist. 2855 do_update_in_use_info_for_chunk(target_chunk, false); 2856 free_chunks(target_chunk_index)->return_chunk_at_head(target_chunk); 2857 2858 // This chunk should now be valid and can be verified. 2859 DEBUG_ONLY(do_verify_chunk(target_chunk)); 2860 2861 // In the remaining space create the remainder chunks. 2862 p += target_chunk->word_size(); 2863 assert(p < region_end, "Sanity"); 2864 2865 while (p < region_end) { 2866 2867 // Find the largest chunk size which fits the alignment requirements at address p. 2868 ChunkIndex this_chunk_index = prev_chunk_index(larger_chunk_index); 2869 size_t this_chunk_word_size = 0; 2870 for(;;) { 2871 this_chunk_word_size = get_size_for_nonhumongous_chunktype(this_chunk_index, is_class()); 2872 if (is_aligned(p, this_chunk_word_size * BytesPerWord)) { 2873 break; 2874 } else { 2875 this_chunk_index = prev_chunk_index(this_chunk_index); 2876 assert(this_chunk_index >= target_chunk_index, "Sanity"); 2877 } 2878 } 2879 2880 assert(this_chunk_word_size >= target_chunk_word_size, "Sanity"); 2881 assert(is_aligned(p, this_chunk_word_size * BytesPerWord), "Sanity"); 2882 assert(p + this_chunk_word_size <= region_end, "Sanity"); 2883 2884 // Create splitting chunk. 2885 Metachunk* this_chunk = ::new (p) Metachunk(this_chunk_index, is_class(), this_chunk_word_size, vsn); 2886 assert(this_chunk == (Metachunk*)p, "Sanity"); 2887 this_chunk->set_origin(origin_split); 2888 ocmap->set_chunk_starts_at_address(p, true); 2889 do_update_in_use_info_for_chunk(this_chunk, false); 2890 2891 // This chunk should be valid and can be verified. 2892 DEBUG_ONLY(do_verify_chunk(this_chunk)); 2893 2894 // Return this chunk to freelist and correct counter. 2895 free_chunks(this_chunk_index)->return_chunk_at_head(this_chunk); 2896 _free_chunks_count ++; 2897 2898 log_trace(gc, metaspace, freelist)("Created chunk at " PTR_FORMAT ", word size " 2899 SIZE_FORMAT_HEX " (%s), in split region [" PTR_FORMAT "..." PTR_FORMAT ").", 2900 p2i(this_chunk), this_chunk->word_size(), chunk_size_name(this_chunk_index), 2901 p2i(region_start), p2i(region_end)); 2902 2903 p += this_chunk_word_size; 2904 2905 } 2906 2907 return target_chunk; 2908 } 2909 2910 Metachunk* ChunkManager::free_chunks_get(size_t word_size) { 2911 assert_lock_strong(MetaspaceExpand_lock); 2912 2913 slow_locked_verify(); 2914 2915 Metachunk* chunk = NULL; 2916 bool we_did_split_a_chunk = false; 2917 2918 if (list_index(word_size) != HumongousIndex) { 2919 2920 ChunkList* free_list = find_free_chunks_list(word_size); 2921 assert(free_list != NULL, "Sanity check"); 2922 2923 chunk = free_list->head(); 2924 2925 if (chunk == NULL) { 2926 // Split large chunks into smaller chunks if there are no smaller chunks, just large chunks. 2927 // This is the counterpart of the coalescing-upon-chunk-return. 2928 2929 ChunkIndex target_chunk_index = get_chunk_type_by_size(word_size, is_class()); 2930 2931 // Is there a larger chunk we could split? 2932 Metachunk* larger_chunk = NULL; 2933 ChunkIndex larger_chunk_index = next_chunk_index(target_chunk_index); 2934 while (larger_chunk == NULL && larger_chunk_index < NumberOfFreeLists) { 2935 larger_chunk = free_chunks(larger_chunk_index)->head(); 2936 if (larger_chunk == NULL) { 2937 larger_chunk_index = next_chunk_index(larger_chunk_index); 2938 } 2939 } 2940 2941 if (larger_chunk != NULL) { 2942 assert(larger_chunk->word_size() > word_size, "Sanity"); 2943 assert(larger_chunk->get_chunk_type() == larger_chunk_index, "Sanity"); 2944 2945 // We found a larger chunk. Lets split it up: 2946 // - remove old chunk 2947 // - in its place, create new smaller chunks, with at least one chunk 2948 // being of target size, the others sized as large as possible. This 2949 // is to make sure the resulting chunks are "as coalesced as possible" 2950 // (similar to VirtualSpaceNode::retire()). 2951 // Note: during this operation both ChunkManager and VirtualSpaceNode 2952 // are temporarily invalid, so be careful with asserts. 2953 2954 log_trace(gc, metaspace, freelist)("%s: splitting chunk " PTR_FORMAT 2955 ", word size " SIZE_FORMAT_HEX " (%s), to get a chunk of word size " SIZE_FORMAT_HEX " (%s)...", 2956 (is_class() ? "class space" : "metaspace"), p2i(larger_chunk), larger_chunk->word_size(), 2957 chunk_size_name(larger_chunk_index), word_size, chunk_size_name(target_chunk_index)); 2958 2959 chunk = split_chunk(word_size, larger_chunk); 2960 2961 // This should have worked. 2962 assert(chunk != NULL, "Sanity"); 2963 assert(chunk->word_size() == word_size, "Sanity"); 2964 assert(chunk->is_tagged_free(), "Sanity"); 2965 2966 we_did_split_a_chunk = true; 2967 2968 } 2969 } 2970 2971 if (chunk == NULL) { 2972 return NULL; 2973 } 2974 2975 // Remove the chunk as the head of the list. 2976 free_list->remove_chunk(chunk); 2977 2978 log_trace(gc, metaspace, freelist)("ChunkManager::free_chunks_get: free_list: " PTR_FORMAT " chunks left: " SSIZE_FORMAT ".", 2979 p2i(free_list), free_list->count()); 2980 2981 } else { 2982 chunk = humongous_dictionary()->get_chunk(word_size); 2983 2984 if (chunk == NULL) { 2985 return NULL; 2986 } 2987 2988 log_debug(gc, metaspace, alloc)("Free list allocate humongous chunk size " SIZE_FORMAT " for requested size " SIZE_FORMAT " waste " SIZE_FORMAT, 2989 chunk->word_size(), word_size, chunk->word_size() - word_size); 2990 } 2991 2992 // Chunk has been removed from the chunk manager; update counters. 2993 account_for_removed_chunk(chunk); 2994 do_update_in_use_info_for_chunk(chunk, true); 2995 chunk->container()->inc_container_count(); 2996 chunk->inc_use_count(); 2997 2998 // Remove it from the links to this freelist 2999 chunk->set_next(NULL); 3000 chunk->set_prev(NULL); 3001 3002 // Run some verifications (some more if we did a chunk split) 3003 #ifdef ASSERT 3004 if (VerifyMetaspace) { 3005 locked_verify(); 3006 VirtualSpaceNode* const vsn = chunk->container(); 3007 vsn->verify(); 3008 if (we_did_split_a_chunk) { 3009 vsn->verify_free_chunks_are_ideally_merged(); 3010 } 3011 } 3012 #endif 3013 3014 return chunk; 3015 } 3016 3017 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) { 3018 assert_lock_strong(MetaspaceExpand_lock); 3019 slow_locked_verify(); 3020 3021 // Take from the beginning of the list 3022 Metachunk* chunk = free_chunks_get(word_size); 3023 if (chunk == NULL) { 3024 return NULL; 3025 } 3026 3027 assert((word_size <= chunk->word_size()) || 3028 (list_index(chunk->word_size()) == HumongousIndex), 3029 "Non-humongous variable sized chunk"); 3030 LogTarget(Debug, gc, metaspace, freelist) lt; 3031 if (lt.is_enabled()) { 3032 size_t list_count; 3033 if (list_index(word_size) < HumongousIndex) { 3034 ChunkList* list = find_free_chunks_list(word_size); 3035 list_count = list->count(); 3036 } else { 3037 list_count = humongous_dictionary()->total_count(); 3038 } 3039 LogStream ls(lt); 3040 ls.print("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk " PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ", 3041 p2i(this), p2i(chunk), chunk->word_size(), list_count); 3042 ResourceMark rm; 3043 locked_print_free_chunks(&ls); 3044 ls.cr(); // ~LogStream does not autoflush. 3045 } 3046 3047 return chunk; 3048 } 3049 3050 void ChunkManager::return_single_chunk(ChunkIndex index, Metachunk* chunk) { 3051 assert_lock_strong(MetaspaceExpand_lock); 3052 DEBUG_ONLY(do_verify_chunk(chunk);) 3053 assert(chunk->get_chunk_type() == index, "Chunk does not match expected index."); 3054 assert(chunk != NULL, "Expected chunk."); 3055 assert(chunk->container() != NULL, "Container should have been set."); 3056 assert(chunk->is_tagged_free() == false, "Chunk should be in use."); 3057 index_bounds_check(index); 3058 3059 // Note: mangle *before* returning the chunk to the freelist or dictionary. It does not 3060 // matter for the freelist (non-humongous chunks), but the humongous chunk dictionary 3061 // keeps tree node pointers in the chunk payload area which mangle will overwrite. 3062 DEBUG_ONLY(chunk->mangle(badMetaWordVal);) 3063 3064 if (index != HumongousIndex) { 3065 // Return non-humongous chunk to freelist. 3066 ChunkList* list = free_chunks(index); 3067 assert(list->size() == chunk->word_size(), "Wrong chunk type."); 3068 list->return_chunk_at_head(chunk); 3069 log_trace(gc, metaspace, freelist)("returned one %s chunk at " PTR_FORMAT " to freelist.", 3070 chunk_size_name(index), p2i(chunk)); 3071 } else { 3072 // Return humongous chunk to dictionary. 3073 assert(chunk->word_size() > free_chunks(MediumIndex)->size(), "Wrong chunk type."); 3074 assert(chunk->word_size() % free_chunks(SpecializedIndex)->size() == 0, 3075 "Humongous chunk has wrong alignment."); 3076 _humongous_dictionary.return_chunk(chunk); 3077 log_trace(gc, metaspace, freelist)("returned one %s chunk at " PTR_FORMAT " (word size " SIZE_FORMAT ") to freelist.", 3078 chunk_size_name(index), p2i(chunk), chunk->word_size()); 3079 } 3080 chunk->container()->dec_container_count(); 3081 do_update_in_use_info_for_chunk(chunk, false); 3082 3083 // Chunk has been added; update counters. 3084 account_for_added_chunk(chunk); 3085 3086 // Attempt coalesce returned chunks with its neighboring chunks: 3087 // if this chunk is small or special, attempt to coalesce to a medium chunk. 3088 if (index == SmallIndex || index == SpecializedIndex) { 3089 if (!attempt_to_coalesce_around_chunk(chunk, MediumIndex)) { 3090 // This did not work. But if this chunk is special, we still may form a small chunk? 3091 if (index == SpecializedIndex) { 3092 if (!attempt_to_coalesce_around_chunk(chunk, SmallIndex)) { 3093 // give up. 3094 } 3095 } 3096 } 3097 } 3098 3099 } 3100 3101 void ChunkManager::return_chunk_list(ChunkIndex index, Metachunk* chunks) { 3102 index_bounds_check(index); 3103 if (chunks == NULL) { 3104 return; 3105 } 3106 LogTarget(Trace, gc, metaspace, freelist) log; 3107 if (log.is_enabled()) { // tracing 3108 log.print("returning list of %s chunks...", chunk_size_name(index)); 3109 } 3110 unsigned num_chunks_returned = 0; 3111 size_t size_chunks_returned = 0; 3112 Metachunk* cur = chunks; 3113 while (cur != NULL) { 3114 // Capture the next link before it is changed 3115 // by the call to return_chunk_at_head(); 3116 Metachunk* next = cur->next(); 3117 if (log.is_enabled()) { // tracing 3118 num_chunks_returned ++; 3119 size_chunks_returned += cur->word_size(); 3120 } 3121 return_single_chunk(index, cur); 3122 cur = next; 3123 } 3124 if (log.is_enabled()) { // tracing 3125 log.print("returned %u %s chunks to freelist, total word size " SIZE_FORMAT ".", 3126 num_chunks_returned, chunk_size_name(index), size_chunks_returned); 3127 if (index != HumongousIndex) { 3128 log.print("updated freelist count: " SIZE_FORMAT ".", free_chunks(index)->size()); 3129 } else { 3130 log.print("updated dictionary count " SIZE_FORMAT ".", _humongous_dictionary.total_count()); 3131 } 3132 } 3133 } 3134 3135 void ChunkManager::print_on(outputStream* out) const { 3136 _humongous_dictionary.report_statistics(out); 3137 } 3138 3139 void ChunkManager::collect_statistics(ChunkManagerStatistics* out) const { 3140 MutexLockerEx cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag); 3141 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 3142 out->chunk_stats(i).add(num_free_chunks(i), size_free_chunks_in_bytes(i) / sizeof(MetaWord)); 3143 } 3144 } 3145 3146 // SpaceManager methods 3147 3148 size_t SpaceManager::adjust_initial_chunk_size(size_t requested, bool is_class_space) { 3149 size_t chunk_sizes[] = { 3150 specialized_chunk_size(is_class_space), 3151 small_chunk_size(is_class_space), 3152 medium_chunk_size(is_class_space) 3153 }; 3154 3155 // Adjust up to one of the fixed chunk sizes ... 3156 for (size_t i = 0; i < ARRAY_SIZE(chunk_sizes); i++) { 3157 if (requested <= chunk_sizes[i]) { 3158 return chunk_sizes[i]; 3159 } 3160 } 3161 3162 // ... or return the size as a humongous chunk. 3163 return requested; 3164 } 3165 3166 size_t SpaceManager::adjust_initial_chunk_size(size_t requested) const { 3167 return adjust_initial_chunk_size(requested, is_class()); 3168 } 3169 3170 size_t SpaceManager::get_initial_chunk_size(Metaspace::MetaspaceType type) const { 3171 size_t requested; 3172 3173 if (is_class()) { 3174 switch (type) { 3175 case Metaspace::BootMetaspaceType: requested = Metaspace::first_class_chunk_word_size(); break; 3176 case Metaspace::AnonymousMetaspaceType: requested = ClassSpecializedChunk; break; 3177 case Metaspace::ReflectionMetaspaceType: requested = ClassSpecializedChunk; break; 3178 default: requested = ClassSmallChunk; break; 3179 } 3180 } else { 3181 switch (type) { 3182 case Metaspace::BootMetaspaceType: requested = Metaspace::first_chunk_word_size(); break; 3183 case Metaspace::AnonymousMetaspaceType: requested = SpecializedChunk; break; 3184 case Metaspace::ReflectionMetaspaceType: requested = SpecializedChunk; break; 3185 default: requested = SmallChunk; break; 3186 } 3187 } 3188 3189 // Adjust to one of the fixed chunk sizes (unless humongous) 3190 const size_t adjusted = adjust_initial_chunk_size(requested); 3191 3192 assert(adjusted != 0, "Incorrect initial chunk size. Requested: " 3193 SIZE_FORMAT " adjusted: " SIZE_FORMAT, requested, adjusted); 3194 3195 return adjusted; 3196 } 3197 3198 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) { 3199 size_t count = 0; 3200 Metachunk* chunk = chunks_in_use(i); 3201 while (chunk != NULL) { 3202 count++; 3203 chunk = chunk->next(); 3204 } 3205 return count; 3206 } 3207 3208 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const { 3209 3210 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 3211 Metachunk* chunk = chunks_in_use(i); 3212 st->print("SpaceManager: %s " PTR_FORMAT, 3213 chunk_size_name(i), p2i(chunk)); 3214 if (chunk != NULL) { 3215 st->print_cr(" free " SIZE_FORMAT, 3216 chunk->free_word_size()); 3217 } else { 3218 st->cr(); 3219 } 3220 } 3221 3222 chunk_manager()->locked_print_free_chunks(st); 3223 chunk_manager()->locked_print_sum_free_chunks(st); 3224 } 3225 3226 size_t SpaceManager::calc_chunk_size(size_t word_size) { 3227 3228 // Decide between a small chunk and a medium chunk. Up to 3229 // _small_chunk_limit small chunks can be allocated. 3230 // After that a medium chunk is preferred. 3231 size_t chunk_word_size; 3232 3233 // Special case for anonymous metadata space. 3234 // Anonymous metadata space is usually small, with majority within 1K - 2K range and 3235 // rarely about 4K (64-bits JVM). 3236 // Instead of jumping to SmallChunk after initial chunk exhausted, keeping allocation 3237 // from SpecializeChunk up to _anon_or_delegating_metadata_specialize_chunk_limit (4) 3238 // reduces space waste from 60+% to around 30%. 3239 if ((_space_type == Metaspace::AnonymousMetaspaceType || _space_type == Metaspace::ReflectionMetaspaceType) && 3240 _mdtype == Metaspace::NonClassType && 3241 sum_count_in_chunks_in_use(SpecializedIndex) < _anon_and_delegating_metadata_specialize_chunk_limit && 3242 word_size + Metachunk::overhead() <= SpecializedChunk) { 3243 return SpecializedChunk; 3244 } 3245 3246 if (chunks_in_use(MediumIndex) == NULL && 3247 sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit) { 3248 chunk_word_size = (size_t) small_chunk_size(); 3249 if (word_size + Metachunk::overhead() > small_chunk_size()) { 3250 chunk_word_size = medium_chunk_size(); 3251 } 3252 } else { 3253 chunk_word_size = medium_chunk_size(); 3254 } 3255 3256 // Might still need a humongous chunk. Enforce 3257 // humongous allocations sizes to be aligned up to 3258 // the smallest chunk size. 3259 size_t if_humongous_sized_chunk = 3260 align_up(word_size + Metachunk::overhead(), 3261 smallest_chunk_size()); 3262 chunk_word_size = 3263 MAX2((size_t) chunk_word_size, if_humongous_sized_chunk); 3264 3265 assert(!SpaceManager::is_humongous(word_size) || 3266 chunk_word_size == if_humongous_sized_chunk, 3267 "Size calculation is wrong, word_size " SIZE_FORMAT 3268 " chunk_word_size " SIZE_FORMAT, 3269 word_size, chunk_word_size); 3270 Log(gc, metaspace, alloc) log; 3271 if (log.is_debug() && SpaceManager::is_humongous(word_size)) { 3272 log.debug("Metadata humongous allocation:"); 3273 log.debug(" word_size " PTR_FORMAT, word_size); 3274 log.debug(" chunk_word_size " PTR_FORMAT, chunk_word_size); 3275 log.debug(" chunk overhead " PTR_FORMAT, Metachunk::overhead()); 3276 } 3277 return chunk_word_size; 3278 } 3279 3280 void SpaceManager::track_metaspace_memory_usage() { 3281 if (is_init_completed()) { 3282 if (is_class()) { 3283 MemoryService::track_compressed_class_memory_usage(); 3284 } 3285 MemoryService::track_metaspace_memory_usage(); 3286 } 3287 } 3288 3289 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) { 3290 assert_lock_strong(_lock); 3291 assert(vs_list()->current_virtual_space() != NULL, 3292 "Should have been set"); 3293 assert(current_chunk() == NULL || 3294 current_chunk()->allocate(word_size) == NULL, 3295 "Don't need to expand"); 3296 MutexLockerEx cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag); 3297 3298 if (log_is_enabled(Trace, gc, metaspace, freelist)) { 3299 size_t words_left = 0; 3300 size_t words_used = 0; 3301 if (current_chunk() != NULL) { 3302 words_left = current_chunk()->free_word_size(); 3303 words_used = current_chunk()->used_word_size(); 3304 } 3305 log_trace(gc, metaspace, freelist)("SpaceManager::grow_and_allocate for " SIZE_FORMAT " words " SIZE_FORMAT " words used " SIZE_FORMAT " words left", 3306 word_size, words_used, words_left); 3307 } 3308 3309 // Get another chunk 3310 size_t chunk_word_size = calc_chunk_size(word_size); 3311 Metachunk* next = get_new_chunk(chunk_word_size); 3312 3313 MetaWord* mem = NULL; 3314 3315 // If a chunk was available, add it to the in-use chunk list 3316 // and do an allocation from it. 3317 if (next != NULL) { 3318 // Add to this manager's list of chunks in use. 3319 // If the new chunk is humongous, it was created to serve a single large allocation. In that 3320 // case it usually makes no sense to make it the current chunk, since the next allocation would 3321 // need to allocate a new chunk anyway, while we would now prematurely retire a perfectly 3322 // good chunk which could be used for more normal allocations. 3323 bool make_current = true; 3324 if (next->get_chunk_type() == HumongousIndex && 3325 current_chunk() != NULL) { 3326 make_current = false; 3327 } 3328 add_chunk(next, make_current); 3329 mem = next->allocate(word_size); 3330 } 3331 3332 // Track metaspace memory usage statistic. 3333 track_metaspace_memory_usage(); 3334 3335 return mem; 3336 } 3337 3338 void SpaceManager::print_on(outputStream* st) const { 3339 SpaceManagerStatistics stat; 3340 add_to_statistics(&stat); // will lock _lock. 3341 stat.print_on(st, 1*K, false); 3342 } 3343 3344 SpaceManager::SpaceManager(Metaspace::MetadataType mdtype, 3345 Metaspace::MetaspaceType space_type, 3346 Mutex* lock) : 3347 _mdtype(mdtype), 3348 _space_type(space_type), 3349 _capacity_words(0), 3350 _used_words(0), 3351 _overhead_words(0), 3352 _block_freelists(NULL), 3353 _lock(lock) 3354 { 3355 initialize(); 3356 } 3357 3358 void SpaceManager::account_for_new_chunk(const Metachunk* new_chunk) { 3359 3360 assert_lock_strong(MetaspaceExpand_lock); 3361 3362 _capacity_words += new_chunk->word_size(); 3363 _overhead_words += Metachunk::overhead(); 3364 3365 // Adjust global counters: 3366 MetaspaceUtils::inc_capacity(mdtype(), new_chunk->word_size()); 3367 MetaspaceUtils::inc_overhead(mdtype(), Metachunk::overhead()); 3368 } 3369 3370 void SpaceManager::account_for_allocation(size_t words) { 3371 // Note: we should be locked with the ClassloaderData-specific metaspace lock. 3372 // We may or may not be locked with the global metaspace expansion lock. 3373 assert_lock_strong(lock()); 3374 3375 // Add to the per SpaceManager totals. This can be done non-atomically. 3376 _used_words += words; 3377 3378 // Adjust global counters. This will be done atomically. 3379 MetaspaceUtils::inc_used(mdtype(), words); 3380 } 3381 3382 void SpaceManager::account_for_spacemanager_death() { 3383 3384 assert_lock_strong(MetaspaceExpand_lock); 3385 3386 MetaspaceUtils::dec_capacity(mdtype(), _capacity_words); 3387 MetaspaceUtils::dec_overhead(mdtype(), _overhead_words); 3388 MetaspaceUtils::dec_used(mdtype(), _used_words); 3389 } 3390 3391 void SpaceManager::initialize() { 3392 Metadebug::init_allocation_fail_alot_count(); 3393 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 3394 _chunks_in_use[i] = NULL; 3395 } 3396 _current_chunk = NULL; 3397 log_trace(gc, metaspace, freelist)("SpaceManager(): " PTR_FORMAT, p2i(this)); 3398 } 3399 3400 SpaceManager::~SpaceManager() { 3401 3402 // This call this->_lock which can't be done while holding MetaspaceExpand_lock 3403 DEBUG_ONLY(verify_metrics()); 3404 3405 MutexLockerEx fcl(MetaspaceExpand_lock, 3406 Mutex::_no_safepoint_check_flag); 3407 3408 chunk_manager()->slow_locked_verify(); 3409 3410 account_for_spacemanager_death(); 3411 3412 Log(gc, metaspace, freelist) log; 3413 if (log.is_trace()) { 3414 log.trace("~SpaceManager(): " PTR_FORMAT, p2i(this)); 3415 ResourceMark rm; 3416 LogStream ls(log.trace()); 3417 locked_print_chunks_in_use_on(&ls); 3418 if (block_freelists() != NULL) { 3419 block_freelists()->print_on(&ls); 3420 } 3421 ls.cr(); // ~LogStream does not autoflush. 3422 } 3423 3424 // Add all the chunks in use by this space manager 3425 // to the global list of free chunks. 3426 3427 // Follow each list of chunks-in-use and add them to the 3428 // free lists. Each list is NULL terminated. 3429 3430 for (ChunkIndex i = ZeroIndex; i <= HumongousIndex; i = next_chunk_index(i)) { 3431 Metachunk* chunks = chunks_in_use(i); 3432 chunk_manager()->return_chunk_list(i, chunks); 3433 set_chunks_in_use(i, NULL); 3434 } 3435 3436 chunk_manager()->slow_locked_verify(); 3437 3438 if (_block_freelists != NULL) { 3439 delete _block_freelists; 3440 } 3441 } 3442 3443 void SpaceManager::deallocate(MetaWord* p, size_t word_size) { 3444 assert_lock_strong(lock()); 3445 // Allocations and deallocations are in raw_word_size 3446 size_t raw_word_size = get_allocation_word_size(word_size); 3447 // Lazily create a block_freelist 3448 if (block_freelists() == NULL) { 3449 _block_freelists = new BlockFreelist(); 3450 } 3451 block_freelists()->return_block(p, raw_word_size); 3452 DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_deallocs)); 3453 } 3454 3455 // Adds a chunk to the list of chunks in use. 3456 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) { 3457 3458 assert_lock_strong(_lock); 3459 assert(new_chunk != NULL, "Should not be NULL"); 3460 assert(new_chunk->next() == NULL, "Should not be on a list"); 3461 3462 new_chunk->reset_empty(); 3463 3464 // Find the correct list and and set the current 3465 // chunk for that list. 3466 ChunkIndex index = chunk_manager()->list_index(new_chunk->word_size()); 3467 3468 if (make_current) { 3469 // If we are to make the chunk current, retire the old current chunk and replace 3470 // it with the new chunk. 3471 retire_current_chunk(); 3472 set_current_chunk(new_chunk); 3473 } 3474 3475 // Add the new chunk at the head of its respective chunk list. 3476 new_chunk->set_next(chunks_in_use(index)); 3477 set_chunks_in_use(index, new_chunk); 3478 3479 // Adjust counters. 3480 account_for_new_chunk(new_chunk); 3481 3482 assert(new_chunk->is_empty(), "Not ready for reuse"); 3483 Log(gc, metaspace, freelist) log; 3484 if (log.is_trace()) { 3485 log.trace("SpaceManager::added chunk: "); 3486 ResourceMark rm; 3487 LogStream ls(log.trace()); 3488 new_chunk->print_on(&ls); 3489 chunk_manager()->locked_print_free_chunks(&ls); 3490 ls.cr(); // ~LogStream does not autoflush. 3491 } 3492 } 3493 3494 void SpaceManager::retire_current_chunk() { 3495 if (current_chunk() != NULL) { 3496 size_t remaining_words = current_chunk()->free_word_size(); 3497 if (remaining_words >= SmallBlocks::small_block_min_size()) { 3498 MetaWord* ptr = current_chunk()->allocate(remaining_words); 3499 deallocate(ptr, remaining_words); 3500 account_for_allocation(remaining_words); 3501 } 3502 } 3503 } 3504 3505 Metachunk* SpaceManager::get_new_chunk(size_t chunk_word_size) { 3506 // Get a chunk from the chunk freelist 3507 Metachunk* next = chunk_manager()->chunk_freelist_allocate(chunk_word_size); 3508 3509 if (next == NULL) { 3510 next = vs_list()->get_new_chunk(chunk_word_size, 3511 medium_chunk_bunch()); 3512 } 3513 3514 Log(gc, metaspace, alloc) log; 3515 if (log.is_debug() && next != NULL && 3516 SpaceManager::is_humongous(next->word_size())) { 3517 log.debug(" new humongous chunk word size " PTR_FORMAT, next->word_size()); 3518 } 3519 3520 return next; 3521 } 3522 3523 MetaWord* SpaceManager::allocate(size_t word_size) { 3524 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 3525 size_t raw_word_size = get_allocation_word_size(word_size); 3526 BlockFreelist* fl = block_freelists(); 3527 MetaWord* p = NULL; 3528 3529 DEBUG_ONLY(if (VerifyMetaspace) verify_metrics_locked()); 3530 3531 // Allocation from the dictionary is expensive in the sense that 3532 // the dictionary has to be searched for a size. Don't allocate 3533 // from the dictionary until it starts to get fat. Is this 3534 // a reasonable policy? Maybe an skinny dictionary is fast enough 3535 // for allocations. Do some profiling. JJJ 3536 if (fl != NULL && fl->total_size() > allocation_from_dictionary_limit) { 3537 p = fl->get_block(raw_word_size); 3538 if (p != NULL) { 3539 DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_allocs_from_deallocated_blocks)); 3540 } 3541 } 3542 if (p == NULL) { 3543 p = allocate_work(raw_word_size); 3544 } 3545 3546 return p; 3547 } 3548 3549 // Returns the address of spaced allocated for "word_size". 3550 // This methods does not know about blocks (Metablocks) 3551 MetaWord* SpaceManager::allocate_work(size_t word_size) { 3552 assert_lock_strong(lock()); 3553 #ifdef ASSERT 3554 if (Metadebug::test_metadata_failure()) { 3555 return NULL; 3556 } 3557 #endif 3558 // Is there space in the current chunk? 3559 MetaWord* result = NULL; 3560 3561 if (current_chunk() != NULL) { 3562 result = current_chunk()->allocate(word_size); 3563 } 3564 3565 if (result == NULL) { 3566 result = grow_and_allocate(word_size); 3567 } 3568 3569 if (result != NULL) { 3570 account_for_allocation(word_size); 3571 assert(result != (MetaWord*) chunks_in_use(MediumIndex), 3572 "Head of the list is being allocated"); 3573 } 3574 3575 return result; 3576 } 3577 3578 void SpaceManager::verify() { 3579 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 3580 Metachunk* curr = chunks_in_use(i); 3581 while (curr != NULL) { 3582 DEBUG_ONLY(do_verify_chunk(curr);) 3583 assert(curr->is_tagged_free() == false, "Chunk should be tagged as in use."); 3584 curr = curr->next(); 3585 } 3586 } 3587 } 3588 3589 void SpaceManager::verify_chunk_size(Metachunk* chunk) { 3590 assert(is_humongous(chunk->word_size()) || 3591 chunk->word_size() == medium_chunk_size() || 3592 chunk->word_size() == small_chunk_size() || 3593 chunk->word_size() == specialized_chunk_size(), 3594 "Chunk size is wrong"); 3595 return; 3596 } 3597 3598 void SpaceManager::add_to_statistics_locked(SpaceManagerStatistics* out) const { 3599 assert_lock_strong(lock()); 3600 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 3601 UsedChunksStatistics& chunk_stat = out->chunk_stats(i); 3602 Metachunk* chunk = chunks_in_use(i); 3603 while (chunk != NULL) { 3604 chunk_stat.add_num(1); 3605 chunk_stat.add_cap(chunk->word_size()); 3606 chunk_stat.add_overhead(Metachunk::overhead()); 3607 chunk_stat.add_used(chunk->used_word_size() - Metachunk::overhead()); 3608 if (chunk != current_chunk()) { 3609 chunk_stat.add_waste(chunk->free_word_size()); 3610 } else { 3611 chunk_stat.add_free(chunk->free_word_size()); 3612 } 3613 chunk = chunk->next(); 3614 } 3615 } 3616 if (block_freelists() != NULL) { 3617 out->add_free_blocks_info(block_freelists()->num_blocks(), block_freelists()->total_size()); 3618 } 3619 } 3620 3621 void SpaceManager::add_to_statistics(SpaceManagerStatistics* out) const { 3622 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 3623 add_to_statistics_locked(out); 3624 } 3625 3626 #ifdef ASSERT 3627 void SpaceManager::verify_metrics_locked() const { 3628 assert_lock_strong(lock()); 3629 3630 SpaceManagerStatistics stat; 3631 add_to_statistics_locked(&stat); 3632 3633 UsedChunksStatistics chunk_stats = stat.totals(); 3634 3635 DEBUG_ONLY(chunk_stats.check_sanity()); 3636 3637 assert_counter(_capacity_words, chunk_stats.cap(), "SpaceManager::_capacity_words"); 3638 assert_counter(_used_words, chunk_stats.used(), "SpaceManager::_used_words"); 3639 assert_counter(_overhead_words, chunk_stats.overhead(), "SpaceManager::_overhead_words"); 3640 } 3641 3642 void SpaceManager::verify_metrics() const { 3643 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 3644 verify_metrics_locked(); 3645 } 3646 #endif // ASSERT 3647 3648 3649 3650 // MetaspaceUtils 3651 size_t MetaspaceUtils::_capacity_words [Metaspace:: MetadataTypeCount] = {0, 0}; 3652 size_t MetaspaceUtils::_overhead_words [Metaspace:: MetadataTypeCount] = {0, 0}; 3653 volatile size_t MetaspaceUtils::_used_words [Metaspace:: MetadataTypeCount] = {0, 0}; 3654 3655 // Collect used metaspace statistics. This involves walking the CLDG. The resulting 3656 // output will be the accumulated values for all live metaspaces. 3657 // Note: method does not do any locking. 3658 void MetaspaceUtils::collect_statistics(ClassLoaderMetaspaceStatistics* out) { 3659 out->reset(); 3660 ClassLoaderDataGraphMetaspaceIterator iter; 3661 while (iter.repeat()) { 3662 ClassLoaderMetaspace* msp = iter.get_next(); 3663 if (msp != NULL) { 3664 msp->add_to_statistics(out); 3665 } 3666 } 3667 } 3668 3669 size_t MetaspaceUtils::free_in_vs_bytes(Metaspace::MetadataType mdtype) { 3670 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 3671 return list == NULL ? 0 : list->free_bytes(); 3672 } 3673 3674 size_t MetaspaceUtils::free_in_vs_bytes() { 3675 return free_in_vs_bytes(Metaspace::ClassType) + free_in_vs_bytes(Metaspace::NonClassType); 3676 } 3677 3678 static void inc_stat_nonatomically(size_t* pstat, size_t words) { 3679 assert_lock_strong(MetaspaceExpand_lock); 3680 (*pstat) += words; 3681 } 3682 3683 static void dec_stat_nonatomically(size_t* pstat, size_t words) { 3684 assert_lock_strong(MetaspaceExpand_lock); 3685 const size_t size_now = *pstat; 3686 assert(size_now >= words, "About to decrement counter below zero " 3687 "(current value: " SIZE_FORMAT ", decrement value: " SIZE_FORMAT ".", 3688 size_now, words); 3689 *pstat = size_now - words; 3690 } 3691 3692 static void inc_stat_atomically(volatile size_t* pstat, size_t words) { 3693 Atomic::add(words, pstat); 3694 } 3695 3696 static void dec_stat_atomically(volatile size_t* pstat, size_t words) { 3697 const size_t size_now = *pstat; 3698 assert(size_now >= words, "About to decrement counter below zero " 3699 "(current value: " SIZE_FORMAT ", decrement value: " SIZE_FORMAT ".", 3700 size_now, words); 3701 Atomic::sub(words, pstat); 3702 } 3703 3704 void MetaspaceUtils::dec_capacity(Metaspace::MetadataType mdtype, size_t words) { 3705 dec_stat_nonatomically(&_capacity_words[mdtype], words); 3706 } 3707 void MetaspaceUtils::inc_capacity(Metaspace::MetadataType mdtype, size_t words) { 3708 inc_stat_nonatomically(&_capacity_words[mdtype], words); 3709 } 3710 void MetaspaceUtils::dec_used(Metaspace::MetadataType mdtype, size_t words) { 3711 dec_stat_atomically(&_used_words[mdtype], words); 3712 } 3713 void MetaspaceUtils::inc_used(Metaspace::MetadataType mdtype, size_t words) { 3714 inc_stat_atomically(&_used_words[mdtype], words); 3715 } 3716 void MetaspaceUtils::dec_overhead(Metaspace::MetadataType mdtype, size_t words) { 3717 dec_stat_nonatomically(&_overhead_words[mdtype], words); 3718 } 3719 void MetaspaceUtils::inc_overhead(Metaspace::MetadataType mdtype, size_t words) { 3720 inc_stat_nonatomically(&_overhead_words[mdtype], words); 3721 } 3722 3723 size_t MetaspaceUtils::reserved_bytes(Metaspace::MetadataType mdtype) { 3724 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 3725 return list == NULL ? 0 : list->reserved_bytes(); 3726 } 3727 3728 size_t MetaspaceUtils::committed_bytes(Metaspace::MetadataType mdtype) { 3729 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 3730 return list == NULL ? 0 : list->committed_bytes(); 3731 } 3732 3733 size_t MetaspaceUtils::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); } 3734 3735 size_t MetaspaceUtils::free_chunks_total_words(Metaspace::MetadataType mdtype) { 3736 ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype); 3737 if (chunk_manager == NULL) { 3738 return 0; 3739 } 3740 chunk_manager->slow_verify(); 3741 return chunk_manager->free_chunks_total_words(); 3742 } 3743 3744 size_t MetaspaceUtils::free_chunks_total_bytes(Metaspace::MetadataType mdtype) { 3745 return free_chunks_total_words(mdtype) * BytesPerWord; 3746 } 3747 3748 size_t MetaspaceUtils::free_chunks_total_words() { 3749 return free_chunks_total_words(Metaspace::ClassType) + 3750 free_chunks_total_words(Metaspace::NonClassType); 3751 } 3752 3753 size_t MetaspaceUtils::free_chunks_total_bytes() { 3754 return free_chunks_total_words() * BytesPerWord; 3755 } 3756 3757 bool MetaspaceUtils::has_chunk_free_list(Metaspace::MetadataType mdtype) { 3758 return Metaspace::get_chunk_manager(mdtype) != NULL; 3759 } 3760 3761 MetaspaceChunkFreeListSummary MetaspaceUtils::chunk_free_list_summary(Metaspace::MetadataType mdtype) { 3762 if (!has_chunk_free_list(mdtype)) { 3763 return MetaspaceChunkFreeListSummary(); 3764 } 3765 3766 const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype); 3767 return cm->chunk_free_list_summary(); 3768 } 3769 3770 void MetaspaceUtils::print_metaspace_change(size_t prev_metadata_used) { 3771 log_info(gc, metaspace)("Metaspace: " SIZE_FORMAT "K->" SIZE_FORMAT "K(" SIZE_FORMAT "K)", 3772 prev_metadata_used/K, used_bytes()/K, reserved_bytes()/K); 3773 } 3774 3775 void MetaspaceUtils::print_on(outputStream* out) { 3776 Metaspace::MetadataType nct = Metaspace::NonClassType; 3777 3778 out->print_cr(" Metaspace " 3779 "used " SIZE_FORMAT "K, " 3780 "capacity " SIZE_FORMAT "K, " 3781 "committed " SIZE_FORMAT "K, " 3782 "reserved " SIZE_FORMAT "K", 3783 used_bytes()/K, 3784 capacity_bytes()/K, 3785 committed_bytes()/K, 3786 reserved_bytes()/K); 3787 3788 if (Metaspace::using_class_space()) { 3789 Metaspace::MetadataType ct = Metaspace::ClassType; 3790 out->print_cr(" class space " 3791 "used " SIZE_FORMAT "K, " 3792 "capacity " SIZE_FORMAT "K, " 3793 "committed " SIZE_FORMAT "K, " 3794 "reserved " SIZE_FORMAT "K", 3795 used_bytes(ct)/K, 3796 capacity_bytes(ct)/K, 3797 committed_bytes(ct)/K, 3798 reserved_bytes(ct)/K); 3799 } 3800 } 3801 3802 class PrintCLDMetaspaceInfoClosure : public CLDClosure { 3803 private: 3804 outputStream* const _out; 3805 const size_t _scale; 3806 const bool _do_print; 3807 const bool _break_down_by_chunktype; 3808 3809 public: 3810 3811 uintx _num_loaders; 3812 ClassLoaderMetaspaceStatistics _stats_total; 3813 3814 uintx _num_loaders_by_spacetype [Metaspace::MetaspaceTypeCount]; 3815 ClassLoaderMetaspaceStatistics _stats_by_spacetype [Metaspace::MetaspaceTypeCount]; 3816 3817 public: 3818 PrintCLDMetaspaceInfoClosure(outputStream* out, size_t scale, bool do_print, bool break_down_by_chunktype) 3819 : _out(out), _scale(scale), _do_print(do_print), _break_down_by_chunktype(break_down_by_chunktype) 3820 , _num_loaders(0) 3821 { 3822 memset(_num_loaders_by_spacetype, 0, sizeof(_num_loaders_by_spacetype)); 3823 } 3824 3825 void do_cld(ClassLoaderData* cld) { 3826 3827 assert(SafepointSynchronize::is_at_safepoint(), "Must be at a safepoint"); 3828 3829 ClassLoaderMetaspace* msp = cld->metaspace_or_null(); 3830 if (msp == NULL) { 3831 return; 3832 } 3833 3834 // Collect statistics for this class loader metaspace 3835 ClassLoaderMetaspaceStatistics this_cld_stat; 3836 msp->add_to_statistics(&this_cld_stat); 3837 3838 // And add it to the running totals 3839 _stats_total.add(this_cld_stat); 3840 _num_loaders ++; 3841 _stats_by_spacetype[msp->space_type()].add(this_cld_stat); 3842 _num_loaders_by_spacetype[msp->space_type()] ++; 3843 3844 // Optionally, print. 3845 if (_do_print) { 3846 3847 _out->print(UINTX_FORMAT_W(4) ": ", _num_loaders); 3848 3849 if (cld->is_anonymous()) { 3850 _out->print("ClassLoaderData " PTR_FORMAT " for anonymous class", p2i(cld)); 3851 } else { 3852 ResourceMark rm; 3853 _out->print("ClassLoaderData " PTR_FORMAT " for %s", p2i(cld), cld->loader_name()); 3854 } 3855 3856 if (cld->is_unloading()) { 3857 _out->print(" (unloading)"); 3858 } 3859 3860 this_cld_stat.print_on(_out, _scale, _break_down_by_chunktype); 3861 _out->cr(); 3862 3863 } 3864 3865 } // do_cld 3866 3867 }; 3868 3869 void MetaspaceUtils::print_vs(outputStream* out, size_t scale) { 3870 const size_t reserved_nonclass_words = reserved_bytes(Metaspace::NonClassType) / sizeof(MetaWord); 3871 const size_t committed_nonclass_words = committed_bytes(Metaspace::NonClassType) / sizeof(MetaWord); 3872 { 3873 if (Metaspace::using_class_space()) { 3874 out->print(" Non-class space: "); 3875 } 3876 print_scaled_words(out, reserved_nonclass_words, scale, 7); 3877 out->print(" reserved, "); 3878 print_scaled_words_and_percentage(out, committed_nonclass_words, reserved_nonclass_words, scale, 7); 3879 out->print_cr(" committed "); 3880 3881 if (Metaspace::using_class_space()) { 3882 const size_t reserved_class_words = reserved_bytes(Metaspace::ClassType) / sizeof(MetaWord); 3883 const size_t committed_class_words = committed_bytes(Metaspace::ClassType) / sizeof(MetaWord); 3884 out->print(" Class space: "); 3885 print_scaled_words(out, reserved_class_words, scale, 7); 3886 out->print(" reserved, "); 3887 print_scaled_words_and_percentage(out, committed_class_words, reserved_class_words, scale, 7); 3888 out->print_cr(" committed "); 3889 3890 const size_t reserved_words = reserved_nonclass_words + reserved_class_words; 3891 const size_t committed_words = committed_nonclass_words + committed_class_words; 3892 out->print(" Both: "); 3893 print_scaled_words(out, reserved_words, scale, 7); 3894 out->print(" reserved, "); 3895 print_scaled_words_and_percentage(out, committed_words, reserved_words, scale, 7); 3896 out->print_cr(" committed "); 3897 } 3898 } 3899 } 3900 3901 // This will print out a basic metaspace usage report but 3902 // unlike print_report() is guaranteed not to lock or to walk the CLDG. 3903 void MetaspaceUtils::print_basic_report(outputStream* out, size_t scale) { 3904 3905 out->cr(); 3906 out->print_cr("Usage:"); 3907 3908 if (Metaspace::using_class_space()) { 3909 out->print(" Non-class: "); 3910 } 3911 3912 // In its most basic form, we do not require walking the CLDG. Instead, just print the running totals from 3913 // MetaspaceUtils. 3914 const size_t cap_nc = MetaspaceUtils::capacity_words(Metaspace::NonClassType); 3915 const size_t overhead_nc = MetaspaceUtils::overhead_words(Metaspace::NonClassType); 3916 const size_t used_nc = MetaspaceUtils::used_words(Metaspace::NonClassType); 3917 const size_t free_and_waste_nc = cap_nc - overhead_nc - used_nc; 3918 3919 print_scaled_words(out, cap_nc, scale, 5); 3920 out->print(" capacity, "); 3921 print_scaled_words_and_percentage(out, used_nc, cap_nc, scale, 5); 3922 out->print(" used, "); 3923 print_scaled_words_and_percentage(out, free_and_waste_nc, cap_nc, scale, 5); 3924 out->print(" free+waste, "); 3925 print_scaled_words_and_percentage(out, overhead_nc, cap_nc, scale, 5); 3926 out->print(" overhead. "); 3927 out->cr(); 3928 3929 if (Metaspace::using_class_space()) { 3930 const size_t cap_c = MetaspaceUtils::capacity_words(Metaspace::ClassType); 3931 const size_t overhead_c = MetaspaceUtils::overhead_words(Metaspace::ClassType); 3932 const size_t used_c = MetaspaceUtils::used_words(Metaspace::ClassType); 3933 const size_t free_and_waste_c = cap_c - overhead_c - used_c; 3934 out->print(" Class: "); 3935 print_scaled_words(out, cap_c, scale, 5); 3936 out->print(" capacity, "); 3937 print_scaled_words_and_percentage(out, used_c, cap_c, scale, 5); 3938 out->print(" used, "); 3939 print_scaled_words_and_percentage(out, free_and_waste_c, cap_c, scale, 5); 3940 out->print(" free+waste, "); 3941 print_scaled_words_and_percentage(out, overhead_c, cap_c, scale, 5); 3942 out->print(" overhead. "); 3943 out->cr(); 3944 3945 out->print(" Both: "); 3946 const size_t cap = cap_nc + cap_c; 3947 3948 print_scaled_words(out, cap, scale, 5); 3949 out->print(" capacity, "); 3950 print_scaled_words_and_percentage(out, used_nc + used_c, cap, scale, 5); 3951 out->print(" used, "); 3952 print_scaled_words_and_percentage(out, free_and_waste_nc + free_and_waste_c, cap, scale, 5); 3953 out->print(" free+waste, "); 3954 print_scaled_words_and_percentage(out, overhead_nc + overhead_c, cap, scale, 5); 3955 out->print(" overhead. "); 3956 out->cr(); 3957 } 3958 3959 out->cr(); 3960 out->print_cr("Virtual space:"); 3961 3962 print_vs(out, scale); 3963 3964 out->cr(); 3965 out->print_cr("Chunk freelists:"); 3966 3967 if (Metaspace::using_class_space()) { 3968 out->print(" Non-Class: "); 3969 } 3970 print_human_readable_size(out, Metaspace::chunk_manager_metadata()->free_chunks_total_words(), scale); 3971 out->cr(); 3972 if (Metaspace::using_class_space()) { 3973 out->print(" Class: "); 3974 print_human_readable_size(out, Metaspace::chunk_manager_class()->free_chunks_total_words(), scale); 3975 out->cr(); 3976 out->print(" Both: "); 3977 print_human_readable_size(out, Metaspace::chunk_manager_class()->free_chunks_total_words() + 3978 Metaspace::chunk_manager_metadata()->free_chunks_total_words(), scale); 3979 out->cr(); 3980 } 3981 out->cr(); 3982 3983 } 3984 3985 void MetaspaceUtils::print_report(outputStream* out, size_t scale, int flags) { 3986 3987 const bool print_loaders = (flags & rf_show_loaders) > 0; 3988 const bool print_by_chunktype = (flags & rf_break_down_by_chunktype) > 0; 3989 const bool print_by_spacetype = (flags & rf_break_down_by_spacetype) > 0; 3990 3991 // Some report options require walking the class loader data graph. 3992 PrintCLDMetaspaceInfoClosure cl(out, scale, print_loaders, print_by_chunktype); 3993 if (print_loaders) { 3994 out->cr(); 3995 out->print_cr("Usage per loader:"); 3996 out->cr(); 3997 } 3998 3999 ClassLoaderDataGraph::cld_do(&cl); // collect data and optionally print 4000 4001 // Print totals, broken up by space type. 4002 if (print_by_spacetype) { 4003 out->cr(); 4004 out->print_cr("Usage per space type:"); 4005 out->cr(); 4006 for (int space_type = (int)Metaspace::ZeroMetaspaceType; 4007 space_type < (int)Metaspace::MetaspaceTypeCount; space_type ++) 4008 { 4009 uintx num = cl._num_loaders_by_spacetype[space_type]; 4010 out->print("%s (" UINTX_FORMAT " loader%s)%c", 4011 space_type_name((Metaspace::MetaspaceType)space_type), 4012 num, (num == 1 ? "" : "s"), (num > 0 ? ':' : '.')); 4013 if (num > 0) { 4014 cl._stats_by_spacetype[space_type].print_on(out, scale, print_by_chunktype); 4015 } 4016 out->cr(); 4017 } 4018 } 4019 4020 // Print totals for in-use data: 4021 out->cr(); 4022 out->print_cr("Total Usage ( " UINTX_FORMAT " loader%s)%c", 4023 cl._num_loaders, (cl._num_loaders == 1 ? "" : "s"), (cl._num_loaders > 0 ? ':' : '.')); 4024 4025 cl._stats_total.print_on(out, scale, print_by_chunktype); 4026 4027 // -- Print Virtual space. 4028 out->cr(); 4029 out->print_cr("Virtual space:"); 4030 4031 print_vs(out, scale); 4032 4033 // -- Print VirtualSpaceList details. 4034 if ((flags & rf_show_vslist) > 0) { 4035 out->cr(); 4036 out->print_cr("Virtual space list%s:", Metaspace::using_class_space() ? "s" : ""); 4037 4038 if (Metaspace::using_class_space()) { 4039 out->print_cr(" Non-Class:"); 4040 } 4041 Metaspace::space_list()->print_on(out, scale); 4042 if (Metaspace::using_class_space()) { 4043 out->print_cr(" Class:"); 4044 Metaspace::class_space_list()->print_on(out, scale); 4045 } 4046 } 4047 out->cr(); 4048 4049 // -- Print VirtualSpaceList map. 4050 if ((flags & rf_show_vsmap) > 0) { 4051 out->cr(); 4052 out->print_cr("Virtual space map:"); 4053 4054 if (Metaspace::using_class_space()) { 4055 out->print_cr(" Non-Class:"); 4056 } 4057 Metaspace::space_list()->print_map(out); 4058 if (Metaspace::using_class_space()) { 4059 out->print_cr(" Class:"); 4060 Metaspace::class_space_list()->print_map(out); 4061 } 4062 } 4063 out->cr(); 4064 4065 // -- Print Freelists (ChunkManager) details 4066 out->cr(); 4067 out->print_cr("Chunk freelist%s:", Metaspace::using_class_space() ? "s" : ""); 4068 4069 ChunkManagerStatistics non_class_cm_stat; 4070 Metaspace::chunk_manager_metadata()->collect_statistics(&non_class_cm_stat); 4071 4072 if (Metaspace::using_class_space()) { 4073 out->print_cr(" Non-Class:"); 4074 } 4075 non_class_cm_stat.print_on(out, scale); 4076 4077 if (Metaspace::using_class_space()) { 4078 ChunkManagerStatistics class_cm_stat; 4079 Metaspace::chunk_manager_class()->collect_statistics(&class_cm_stat); 4080 out->print_cr(" Class:"); 4081 class_cm_stat.print_on(out, scale); 4082 } 4083 4084 // As a convenience, print a summary of common waste. 4085 out->cr(); 4086 out->print("Waste "); 4087 // For all wastages, print percentages from total. As total use the total size of memory committed for metaspace. 4088 const size_t committed_words = committed_bytes() / BytesPerWord; 4089 4090 out->print("(percentages refer to total committed size "); 4091 print_scaled_words(out, committed_words, scale); 4092 out->print_cr("):"); 4093 4094 // Print space committed but not yet used by any class loader 4095 const size_t unused_words_in_vs = MetaspaceUtils::free_in_vs_bytes() / BytesPerWord; 4096 out->print(" Committed unused: "); 4097 print_scaled_words_and_percentage(out, unused_words_in_vs, committed_words, scale, 6); 4098 out->cr(); 4099 4100 // Print waste for in-use chunks. 4101 UsedChunksStatistics ucs_nonclass = cl._stats_total.nonclass_sm_stats().totals(); 4102 UsedChunksStatistics ucs_class = cl._stats_total.class_sm_stats().totals(); 4103 UsedChunksStatistics ucs_all; 4104 ucs_all.add(ucs_nonclass); 4105 ucs_all.add(ucs_class); 4106 4107 out->print(" Waste in chunks in use: "); 4108 print_scaled_words_and_percentage(out, ucs_all.waste(), committed_words, scale, 6); 4109 out->cr(); 4110 out->print(" Free in chunks in use: "); 4111 print_scaled_words_and_percentage(out, ucs_all.free(), committed_words, scale, 6); 4112 out->cr(); 4113 out->print(" Overhead in chunks in use: "); 4114 print_scaled_words_and_percentage(out, ucs_all.overhead(), committed_words, scale, 6); 4115 out->cr(); 4116 4117 // Print waste in free chunks. 4118 const size_t total_capacity_in_free_chunks = 4119 Metaspace::chunk_manager_metadata()->free_chunks_total_words() + 4120 (Metaspace::using_class_space() ? Metaspace::chunk_manager_class()->free_chunks_total_words() : 0); 4121 out->print(" In free chunks: "); 4122 print_scaled_words_and_percentage(out, total_capacity_in_free_chunks, committed_words, scale, 6); 4123 out->cr(); 4124 4125 // Print waste in deallocated blocks. 4126 const uintx free_blocks_num = 4127 cl._stats_total.nonclass_sm_stats().free_blocks_num() + 4128 cl._stats_total.class_sm_stats().free_blocks_num(); 4129 const size_t free_blocks_cap_words = 4130 cl._stats_total.nonclass_sm_stats().free_blocks_cap_words() + 4131 cl._stats_total.class_sm_stats().free_blocks_cap_words(); 4132 out->print("Deallocated from chunks in use: "); 4133 print_scaled_words_and_percentage(out, free_blocks_cap_words, committed_words, scale, 6); 4134 out->print(" (" UINTX_FORMAT " blocks)", free_blocks_num); 4135 out->cr(); 4136 4137 // Print total waste. 4138 const size_t total_waste = ucs_all.waste() + ucs_all.free() + ucs_all.overhead() + total_capacity_in_free_chunks 4139 + free_blocks_cap_words + unused_words_in_vs; 4140 out->print(" -total-: "); 4141 print_scaled_words_and_percentage(out, total_waste, committed_words, scale, 6); 4142 out->cr(); 4143 4144 // Print internal statistics 4145 #ifdef ASSERT 4146 out->cr(); 4147 out->cr(); 4148 out->print_cr("Internal statistics:"); 4149 out->cr(); 4150 out->print_cr("Number of allocations: " UINTX_FORMAT ".", g_internal_statistics.num_allocs); 4151 out->print_cr("Number of space births: " UINTX_FORMAT ".", g_internal_statistics.num_metaspace_births); 4152 out->print_cr("Number of space deaths: " UINTX_FORMAT ".", g_internal_statistics.num_metaspace_deaths); 4153 out->print_cr("Number of virtual space node births: " UINTX_FORMAT ".", g_internal_statistics.num_vsnodes_created); 4154 out->print_cr("Number of virtual space node deaths: " UINTX_FORMAT ".", g_internal_statistics.num_vsnodes_purged); 4155 out->print_cr("Number of times virtual space nodes were expanded: " UINTX_FORMAT ".", g_internal_statistics.num_committed_space_expanded); 4156 out->print_cr("Number of deallocations: " UINTX_FORMAT " (" UINTX_FORMAT " external).", g_internal_statistics.num_deallocs, g_internal_statistics.num_external_deallocs); 4157 out->print_cr("Allocations from deallocated blocks: " UINTX_FORMAT ".", g_internal_statistics.num_allocs_from_deallocated_blocks); 4158 out->cr(); 4159 #endif 4160 4161 // Print some interesting settings 4162 out->cr(); 4163 out->cr(); 4164 out->print("MaxMetaspaceSize: "); 4165 print_human_readable_size(out, MaxMetaspaceSize, scale); 4166 out->cr(); 4167 out->print("InitialBootClassLoaderMetaspaceSize: "); 4168 print_human_readable_size(out, InitialBootClassLoaderMetaspaceSize, scale); 4169 out->cr(); 4170 4171 out->print("UseCompressedClassPointers: %s", UseCompressedClassPointers ? "true" : "false"); 4172 out->cr(); 4173 if (Metaspace::using_class_space()) { 4174 out->print("CompressedClassSpaceSize: "); 4175 print_human_readable_size(out, CompressedClassSpaceSize, scale); 4176 } 4177 4178 out->cr(); 4179 out->cr(); 4180 4181 } // MetaspaceUtils::print_report() 4182 4183 // Prints an ASCII representation of the given space. 4184 void MetaspaceUtils::print_metaspace_map(outputStream* out, Metaspace::MetadataType mdtype) { 4185 MutexLockerEx cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag); 4186 const bool for_class = mdtype == Metaspace::ClassType ? true : false; 4187 VirtualSpaceList* const vsl = for_class ? Metaspace::class_space_list() : Metaspace::space_list(); 4188 if (vsl != NULL) { 4189 if (for_class) { 4190 if (!Metaspace::using_class_space()) { 4191 out->print_cr("No Class Space."); 4192 return; 4193 } 4194 out->print_raw("---- Metaspace Map (Class Space) ----"); 4195 } else { 4196 out->print_raw("---- Metaspace Map (Non-Class Space) ----"); 4197 } 4198 // Print legend: 4199 out->cr(); 4200 out->print_cr("Chunk Types (uppercase chunks are in use): x-specialized, s-small, m-medium, h-humongous."); 4201 out->cr(); 4202 VirtualSpaceList* const vsl = for_class ? Metaspace::class_space_list() : Metaspace::space_list(); 4203 vsl->print_map(out); 4204 out->cr(); 4205 } 4206 } 4207 4208 void MetaspaceUtils::verify_free_chunks() { 4209 Metaspace::chunk_manager_metadata()->verify(); 4210 if (Metaspace::using_class_space()) { 4211 Metaspace::chunk_manager_class()->verify(); 4212 } 4213 } 4214 4215 void MetaspaceUtils::verify_metrics() { 4216 #ifdef ASSERT 4217 // Please note: there are time windows where the internal counters are out of sync with 4218 // reality. For example, when a newly created ClassLoaderMetaspace creates its first chunk - 4219 // the ClassLoaderMetaspace is not yet attached to its ClassLoaderData object and hence will 4220 // not be counted when iterating the CLDG. So be careful when you call this method. 4221 ClassLoaderMetaspaceStatistics total_stat; 4222 collect_statistics(&total_stat); 4223 UsedChunksStatistics nonclass_chunk_stat = total_stat.nonclass_sm_stats().totals(); 4224 UsedChunksStatistics class_chunk_stat = total_stat.class_sm_stats().totals(); 4225 4226 bool mismatch = false; 4227 for (int i = 0; i < Metaspace::MetadataTypeCount; i ++) { 4228 Metaspace::MetadataType mdtype = (Metaspace::MetadataType)i; 4229 UsedChunksStatistics chunk_stat = total_stat.sm_stats(mdtype).totals(); 4230 if (capacity_words(mdtype) != chunk_stat.cap() || 4231 used_words(mdtype) != chunk_stat.used() || 4232 overhead_words(mdtype) != chunk_stat.overhead()) { 4233 mismatch = true; 4234 tty->print_cr("MetaspaceUtils::verify_metrics: counter mismatch for mdtype=%u:", mdtype); 4235 tty->print_cr("Expected cap " SIZE_FORMAT ", used " SIZE_FORMAT ", overhead " SIZE_FORMAT ".", 4236 capacity_words(mdtype), used_words(mdtype), overhead_words(mdtype)); 4237 tty->print_cr("Got cap " SIZE_FORMAT ", used " SIZE_FORMAT ", overhead " SIZE_FORMAT ".", 4238 chunk_stat.cap(), chunk_stat.used(), chunk_stat.overhead()); 4239 tty->flush(); 4240 } 4241 } 4242 assert(mismatch == false, "MetaspaceUtils::verify_metrics: counter mismatch."); 4243 #endif 4244 } 4245 4246 4247 // Metaspace methods 4248 4249 size_t Metaspace::_first_chunk_word_size = 0; 4250 size_t Metaspace::_first_class_chunk_word_size = 0; 4251 4252 size_t Metaspace::_commit_alignment = 0; 4253 size_t Metaspace::_reserve_alignment = 0; 4254 4255 VirtualSpaceList* Metaspace::_space_list = NULL; 4256 VirtualSpaceList* Metaspace::_class_space_list = NULL; 4257 4258 ChunkManager* Metaspace::_chunk_manager_metadata = NULL; 4259 ChunkManager* Metaspace::_chunk_manager_class = NULL; 4260 4261 #define VIRTUALSPACEMULTIPLIER 2 4262 4263 #ifdef _LP64 4264 static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1); 4265 4266 void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) { 4267 assert(!DumpSharedSpaces, "narrow_klass is set by MetaspaceShared class."); 4268 // Figure out the narrow_klass_base and the narrow_klass_shift. The 4269 // narrow_klass_base is the lower of the metaspace base and the cds base 4270 // (if cds is enabled). The narrow_klass_shift depends on the distance 4271 // between the lower base and higher address. 4272 address lower_base; 4273 address higher_address; 4274 #if INCLUDE_CDS 4275 if (UseSharedSpaces) { 4276 higher_address = MAX2((address)(cds_base + MetaspaceShared::core_spaces_size()), 4277 (address)(metaspace_base + compressed_class_space_size())); 4278 lower_base = MIN2(metaspace_base, cds_base); 4279 } else 4280 #endif 4281 { 4282 higher_address = metaspace_base + compressed_class_space_size(); 4283 lower_base = metaspace_base; 4284 4285 uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes; 4286 // If compressed class space fits in lower 32G, we don't need a base. 4287 if (higher_address <= (address)klass_encoding_max) { 4288 lower_base = 0; // Effectively lower base is zero. 4289 } 4290 } 4291 4292 Universe::set_narrow_klass_base(lower_base); 4293 4294 // CDS uses LogKlassAlignmentInBytes for narrow_klass_shift. See 4295 // MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() for 4296 // how dump time narrow_klass_shift is set. Although, CDS can work 4297 // with zero-shift mode also, to be consistent with AOT it uses 4298 // LogKlassAlignmentInBytes for klass shift so archived java heap objects 4299 // can be used at same time as AOT code. 4300 if (!UseSharedSpaces 4301 && (uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) { 4302 Universe::set_narrow_klass_shift(0); 4303 } else { 4304 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes); 4305 } 4306 AOTLoader::set_narrow_klass_shift(); 4307 } 4308 4309 #if INCLUDE_CDS 4310 // Return TRUE if the specified metaspace_base and cds_base are close enough 4311 // to work with compressed klass pointers. 4312 bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) { 4313 assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS"); 4314 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); 4315 address lower_base = MIN2((address)metaspace_base, cds_base); 4316 address higher_address = MAX2((address)(cds_base + MetaspaceShared::core_spaces_size()), 4317 (address)(metaspace_base + compressed_class_space_size())); 4318 return ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax); 4319 } 4320 #endif 4321 4322 // Try to allocate the metaspace at the requested addr. 4323 void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) { 4324 assert(!DumpSharedSpaces, "compress klass space is allocated by MetaspaceShared class."); 4325 assert(using_class_space(), "called improperly"); 4326 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); 4327 assert(compressed_class_space_size() < KlassEncodingMetaspaceMax, 4328 "Metaspace size is too big"); 4329 assert_is_aligned(requested_addr, _reserve_alignment); 4330 assert_is_aligned(cds_base, _reserve_alignment); 4331 assert_is_aligned(compressed_class_space_size(), _reserve_alignment); 4332 4333 // Don't use large pages for the class space. 4334 bool large_pages = false; 4335 4336 #if !(defined(AARCH64) || defined(AIX)) 4337 ReservedSpace metaspace_rs = ReservedSpace(compressed_class_space_size(), 4338 _reserve_alignment, 4339 large_pages, 4340 requested_addr); 4341 #else // AARCH64 4342 ReservedSpace metaspace_rs; 4343 4344 // Our compressed klass pointers may fit nicely into the lower 32 4345 // bits. 4346 if ((uint64_t)requested_addr + compressed_class_space_size() < 4*G) { 4347 metaspace_rs = ReservedSpace(compressed_class_space_size(), 4348 _reserve_alignment, 4349 large_pages, 4350 requested_addr); 4351 } 4352 4353 if (! metaspace_rs.is_reserved()) { 4354 // Aarch64: Try to align metaspace so that we can decode a compressed 4355 // klass with a single MOVK instruction. We can do this iff the 4356 // compressed class base is a multiple of 4G. 4357 // Aix: Search for a place where we can find memory. If we need to load 4358 // the base, 4G alignment is helpful, too. 4359 size_t increment = AARCH64_ONLY(4*)G; 4360 for (char *a = align_up(requested_addr, increment); 4361 a < (char*)(1024*G); 4362 a += increment) { 4363 if (a == (char *)(32*G)) { 4364 // Go faster from here on. Zero-based is no longer possible. 4365 increment = 4*G; 4366 } 4367 4368 #if INCLUDE_CDS 4369 if (UseSharedSpaces 4370 && ! can_use_cds_with_metaspace_addr(a, cds_base)) { 4371 // We failed to find an aligned base that will reach. Fall 4372 // back to using our requested addr. 4373 metaspace_rs = ReservedSpace(compressed_class_space_size(), 4374 _reserve_alignment, 4375 large_pages, 4376 requested_addr); 4377 break; 4378 } 4379 #endif 4380 4381 metaspace_rs = ReservedSpace(compressed_class_space_size(), 4382 _reserve_alignment, 4383 large_pages, 4384 a); 4385 if (metaspace_rs.is_reserved()) 4386 break; 4387 } 4388 } 4389 4390 #endif // AARCH64 4391 4392 if (!metaspace_rs.is_reserved()) { 4393 #if INCLUDE_CDS 4394 if (UseSharedSpaces) { 4395 size_t increment = align_up(1*G, _reserve_alignment); 4396 4397 // Keep trying to allocate the metaspace, increasing the requested_addr 4398 // by 1GB each time, until we reach an address that will no longer allow 4399 // use of CDS with compressed klass pointers. 4400 char *addr = requested_addr; 4401 while (!metaspace_rs.is_reserved() && (addr + increment > addr) && 4402 can_use_cds_with_metaspace_addr(addr + increment, cds_base)) { 4403 addr = addr + increment; 4404 metaspace_rs = ReservedSpace(compressed_class_space_size(), 4405 _reserve_alignment, large_pages, addr); 4406 } 4407 } 4408 #endif 4409 // If no successful allocation then try to allocate the space anywhere. If 4410 // that fails then OOM doom. At this point we cannot try allocating the 4411 // metaspace as if UseCompressedClassPointers is off because too much 4412 // initialization has happened that depends on UseCompressedClassPointers. 4413 // So, UseCompressedClassPointers cannot be turned off at this point. 4414 if (!metaspace_rs.is_reserved()) { 4415 metaspace_rs = ReservedSpace(compressed_class_space_size(), 4416 _reserve_alignment, large_pages); 4417 if (!metaspace_rs.is_reserved()) { 4418 vm_exit_during_initialization(err_msg("Could not allocate metaspace: " SIZE_FORMAT " bytes", 4419 compressed_class_space_size())); 4420 } 4421 } 4422 } 4423 4424 // If we got here then the metaspace got allocated. 4425 MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass); 4426 4427 #if INCLUDE_CDS 4428 // Verify that we can use shared spaces. Otherwise, turn off CDS. 4429 if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) { 4430 FileMapInfo::stop_sharing_and_unmap( 4431 "Could not allocate metaspace at a compatible address"); 4432 } 4433 #endif 4434 set_narrow_klass_base_and_shift((address)metaspace_rs.base(), 4435 UseSharedSpaces ? (address)cds_base : 0); 4436 4437 initialize_class_space(metaspace_rs); 4438 4439 LogTarget(Trace, gc, metaspace) lt; 4440 if (lt.is_enabled()) { 4441 ResourceMark rm; 4442 LogStream ls(lt); 4443 print_compressed_class_space(&ls, requested_addr); 4444 ls.cr(); // ~LogStream does not autoflush. 4445 } 4446 } 4447 4448 void Metaspace::print_compressed_class_space(outputStream* st, const char* requested_addr) { 4449 st->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: %d", 4450 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift()); 4451 if (_class_space_list != NULL) { 4452 address base = (address)_class_space_list->current_virtual_space()->bottom(); 4453 st->print("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT, 4454 compressed_class_space_size(), p2i(base)); 4455 if (requested_addr != 0) { 4456 st->print(" Req Addr: " PTR_FORMAT, p2i(requested_addr)); 4457 } 4458 st->cr(); 4459 } 4460 } 4461 4462 // For UseCompressedClassPointers the class space is reserved above the top of 4463 // the Java heap. The argument passed in is at the base of the compressed space. 4464 void Metaspace::initialize_class_space(ReservedSpace rs) { 4465 // The reserved space size may be bigger because of alignment, esp with UseLargePages 4466 assert(rs.size() >= CompressedClassSpaceSize, 4467 SIZE_FORMAT " != " SIZE_FORMAT, rs.size(), CompressedClassSpaceSize); 4468 assert(using_class_space(), "Must be using class space"); 4469 _class_space_list = new VirtualSpaceList(rs); 4470 _chunk_manager_class = new ChunkManager(true/*is_class*/); 4471 4472 if (!_class_space_list->initialization_succeeded()) { 4473 vm_exit_during_initialization("Failed to setup compressed class space virtual space list."); 4474 } 4475 } 4476 4477 #endif 4478 4479 void Metaspace::ergo_initialize() { 4480 if (DumpSharedSpaces) { 4481 // Using large pages when dumping the shared archive is currently not implemented. 4482 FLAG_SET_ERGO(bool, UseLargePagesInMetaspace, false); 4483 } 4484 4485 size_t page_size = os::vm_page_size(); 4486 if (UseLargePages && UseLargePagesInMetaspace) { 4487 page_size = os::large_page_size(); 4488 } 4489 4490 _commit_alignment = page_size; 4491 _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity()); 4492 4493 // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will 4494 // override if MaxMetaspaceSize was set on the command line or not. 4495 // This information is needed later to conform to the specification of the 4496 // java.lang.management.MemoryUsage API. 4497 // 4498 // Ideally, we would be able to set the default value of MaxMetaspaceSize in 4499 // globals.hpp to the aligned value, but this is not possible, since the 4500 // alignment depends on other flags being parsed. 4501 MaxMetaspaceSize = align_down_bounded(MaxMetaspaceSize, _reserve_alignment); 4502 4503 if (MetaspaceSize > MaxMetaspaceSize) { 4504 MetaspaceSize = MaxMetaspaceSize; 4505 } 4506 4507 MetaspaceSize = align_down_bounded(MetaspaceSize, _commit_alignment); 4508 4509 assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize"); 4510 4511 MinMetaspaceExpansion = align_down_bounded(MinMetaspaceExpansion, _commit_alignment); 4512 MaxMetaspaceExpansion = align_down_bounded(MaxMetaspaceExpansion, _commit_alignment); 4513 4514 CompressedClassSpaceSize = align_down_bounded(CompressedClassSpaceSize, _reserve_alignment); 4515 4516 // Initial virtual space size will be calculated at global_initialize() 4517 size_t min_metaspace_sz = 4518 VIRTUALSPACEMULTIPLIER * InitialBootClassLoaderMetaspaceSize; 4519 if (UseCompressedClassPointers) { 4520 if ((min_metaspace_sz + CompressedClassSpaceSize) > MaxMetaspaceSize) { 4521 if (min_metaspace_sz >= MaxMetaspaceSize) { 4522 vm_exit_during_initialization("MaxMetaspaceSize is too small."); 4523 } else { 4524 FLAG_SET_ERGO(size_t, CompressedClassSpaceSize, 4525 MaxMetaspaceSize - min_metaspace_sz); 4526 } 4527 } 4528 } else if (min_metaspace_sz >= MaxMetaspaceSize) { 4529 FLAG_SET_ERGO(size_t, InitialBootClassLoaderMetaspaceSize, 4530 min_metaspace_sz); 4531 } 4532 4533 set_compressed_class_space_size(CompressedClassSpaceSize); 4534 } 4535 4536 void Metaspace::global_initialize() { 4537 MetaspaceGC::initialize(); 4538 4539 #if INCLUDE_CDS 4540 if (DumpSharedSpaces) { 4541 MetaspaceShared::initialize_dumptime_shared_and_meta_spaces(); 4542 } else if (UseSharedSpaces) { 4543 // If any of the archived space fails to map, UseSharedSpaces 4544 // is reset to false. Fall through to the 4545 // (!DumpSharedSpaces && !UseSharedSpaces) case to set up class 4546 // metaspace. 4547 MetaspaceShared::initialize_runtime_shared_and_meta_spaces(); 4548 } 4549 4550 if (!DumpSharedSpaces && !UseSharedSpaces) 4551 #endif // INCLUDE_CDS 4552 { 4553 #ifdef _LP64 4554 if (using_class_space()) { 4555 char* base = (char*)align_up(Universe::heap()->reserved_region().end(), _reserve_alignment); 4556 allocate_metaspace_compressed_klass_ptrs(base, 0); 4557 } 4558 #endif // _LP64 4559 } 4560 4561 // Initialize these before initializing the VirtualSpaceList 4562 _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord; 4563 _first_chunk_word_size = align_word_size_up(_first_chunk_word_size); 4564 // Make the first class chunk bigger than a medium chunk so it's not put 4565 // on the medium chunk list. The next chunk will be small and progress 4566 // from there. This size calculated by -version. 4567 _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6, 4568 (CompressedClassSpaceSize/BytesPerWord)*2); 4569 _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size); 4570 // Arbitrarily set the initial virtual space to a multiple 4571 // of the boot class loader size. 4572 size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size; 4573 word_size = align_up(word_size, Metaspace::reserve_alignment_words()); 4574 4575 // Initialize the list of virtual spaces. 4576 _space_list = new VirtualSpaceList(word_size); 4577 _chunk_manager_metadata = new ChunkManager(false/*metaspace*/); 4578 4579 if (!_space_list->initialization_succeeded()) { 4580 vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL); 4581 } 4582 4583 _tracer = new MetaspaceTracer(); 4584 } 4585 4586 void Metaspace::post_initialize() { 4587 MetaspaceGC::post_initialize(); 4588 } 4589 4590 void Metaspace::verify_global_initialization() { 4591 assert(space_list() != NULL, "Metadata VirtualSpaceList has not been initialized"); 4592 assert(chunk_manager_metadata() != NULL, "Metadata ChunkManager has not been initialized"); 4593 4594 if (using_class_space()) { 4595 assert(class_space_list() != NULL, "Class VirtualSpaceList has not been initialized"); 4596 assert(chunk_manager_class() != NULL, "Class ChunkManager has not been initialized"); 4597 } 4598 } 4599 4600 size_t Metaspace::align_word_size_up(size_t word_size) { 4601 size_t byte_size = word_size * wordSize; 4602 return ReservedSpace::allocation_align_size_up(byte_size) / wordSize; 4603 } 4604 4605 MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size, 4606 MetaspaceObj::Type type, TRAPS) { 4607 assert(!_frozen, "sanity"); 4608 if (HAS_PENDING_EXCEPTION) { 4609 assert(false, "Should not allocate with exception pending"); 4610 return NULL; // caller does a CHECK_NULL too 4611 } 4612 4613 assert(loader_data != NULL, "Should never pass around a NULL loader_data. " 4614 "ClassLoaderData::the_null_class_loader_data() should have been used."); 4615 4616 MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType; 4617 4618 // Try to allocate metadata. 4619 MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype); 4620 4621 if (result == NULL) { 4622 tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype); 4623 4624 // Allocation failed. 4625 if (is_init_completed() && !(DumpSharedSpaces && THREAD->is_VM_thread())) { 4626 // Only start a GC if the bootstrapping has completed. 4627 // Also, we cannot GC if we are at the end of the CDS dumping stage which runs inside 4628 // the VM thread. 4629 4630 // Try to clean out some memory and retry. 4631 result = Universe::heap()->satisfy_failed_metadata_allocation(loader_data, word_size, mdtype); 4632 } 4633 } 4634 4635 if (result == NULL) { 4636 if (DumpSharedSpaces) { 4637 // CDS dumping keeps loading classes, so if we hit an OOM we probably will keep hitting OOM. 4638 // We should abort to avoid generating a potentially bad archive. 4639 tty->print_cr("Failed allocating metaspace object type %s of size " SIZE_FORMAT ". CDS dump aborted.", 4640 MetaspaceObj::type_name(type), word_size * BytesPerWord); 4641 tty->print_cr("Please increase MaxMetaspaceSize (currently " SIZE_FORMAT " bytes).", MaxMetaspaceSize); 4642 vm_exit(1); 4643 } 4644 report_metadata_oome(loader_data, word_size, type, mdtype, CHECK_NULL); 4645 } 4646 4647 // Zero initialize. 4648 Copy::fill_to_words((HeapWord*)result, word_size, 0); 4649 4650 return result; 4651 } 4652 4653 void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) { 4654 tracer()->report_metadata_oom(loader_data, word_size, type, mdtype); 4655 4656 // If result is still null, we are out of memory. 4657 Log(gc, metaspace, freelist) log; 4658 if (log.is_info()) { 4659 log.info("Metaspace (%s) allocation failed for size " SIZE_FORMAT, 4660 is_class_space_allocation(mdtype) ? "class" : "data", word_size); 4661 ResourceMark rm; 4662 if (log.is_debug()) { 4663 if (loader_data->metaspace_or_null() != NULL) { 4664 LogStream ls(log.debug()); 4665 loader_data->print_value_on(&ls); 4666 ls.cr(); // ~LogStream does not autoflush. 4667 } 4668 } 4669 LogStream ls(log.info()); 4670 // In case of an OOM, log out a short but still useful report. 4671 MetaspaceUtils::print_basic_report(&ls, 0); 4672 ls.cr(); // ~LogStream does not autoflush. 4673 } 4674 4675 bool out_of_compressed_class_space = false; 4676 if (is_class_space_allocation(mdtype)) { 4677 ClassLoaderMetaspace* metaspace = loader_data->metaspace_non_null(); 4678 out_of_compressed_class_space = 4679 MetaspaceUtils::committed_bytes(Metaspace::ClassType) + 4680 (metaspace->class_chunk_size(word_size) * BytesPerWord) > 4681 CompressedClassSpaceSize; 4682 } 4683 4684 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support 4685 const char* space_string = out_of_compressed_class_space ? 4686 "Compressed class space" : "Metaspace"; 4687 4688 report_java_out_of_memory(space_string); 4689 4690 if (JvmtiExport::should_post_resource_exhausted()) { 4691 JvmtiExport::post_resource_exhausted( 4692 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR, 4693 space_string); 4694 } 4695 4696 if (!is_init_completed()) { 4697 vm_exit_during_initialization("OutOfMemoryError", space_string); 4698 } 4699 4700 if (out_of_compressed_class_space) { 4701 THROW_OOP(Universe::out_of_memory_error_class_metaspace()); 4702 } else { 4703 THROW_OOP(Universe::out_of_memory_error_metaspace()); 4704 } 4705 } 4706 4707 const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) { 4708 switch (mdtype) { 4709 case Metaspace::ClassType: return "Class"; 4710 case Metaspace::NonClassType: return "Metadata"; 4711 default: 4712 assert(false, "Got bad mdtype: %d", (int) mdtype); 4713 return NULL; 4714 } 4715 } 4716 4717 void Metaspace::purge(MetadataType mdtype) { 4718 get_space_list(mdtype)->purge(get_chunk_manager(mdtype)); 4719 } 4720 4721 void Metaspace::purge() { 4722 MutexLockerEx cl(MetaspaceExpand_lock, 4723 Mutex::_no_safepoint_check_flag); 4724 purge(NonClassType); 4725 if (using_class_space()) { 4726 purge(ClassType); 4727 } 4728 } 4729 4730 bool Metaspace::contains(const void* ptr) { 4731 if (MetaspaceShared::is_in_shared_metaspace(ptr)) { 4732 return true; 4733 } 4734 return contains_non_shared(ptr); 4735 } 4736 4737 bool Metaspace::contains_non_shared(const void* ptr) { 4738 if (using_class_space() && get_space_list(ClassType)->contains(ptr)) { 4739 return true; 4740 } 4741 4742 return get_space_list(NonClassType)->contains(ptr); 4743 } 4744 4745 // ClassLoaderMetaspace 4746 4747 ClassLoaderMetaspace::ClassLoaderMetaspace(Mutex* lock, Metaspace::MetaspaceType type) 4748 : _lock(lock) 4749 , _space_type(type) 4750 , _vsm(NULL) 4751 , _class_vsm(NULL) 4752 { 4753 initialize(lock, type); 4754 } 4755 4756 ClassLoaderMetaspace::~ClassLoaderMetaspace() { 4757 DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_metaspace_deaths)); 4758 delete _vsm; 4759 if (Metaspace::using_class_space()) { 4760 delete _class_vsm; 4761 } 4762 } 4763 4764 void ClassLoaderMetaspace::initialize_first_chunk(Metaspace::MetaspaceType type, Metaspace::MetadataType mdtype) { 4765 Metachunk* chunk = get_initialization_chunk(type, mdtype); 4766 if (chunk != NULL) { 4767 // Add to this manager's list of chunks in use and make it the current_chunk(). 4768 get_space_manager(mdtype)->add_chunk(chunk, true); 4769 } 4770 } 4771 4772 Metachunk* ClassLoaderMetaspace::get_initialization_chunk(Metaspace::MetaspaceType type, Metaspace::MetadataType mdtype) { 4773 size_t chunk_word_size = get_space_manager(mdtype)->get_initial_chunk_size(type); 4774 4775 // Get a chunk from the chunk freelist 4776 Metachunk* chunk = Metaspace::get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size); 4777 4778 if (chunk == NULL) { 4779 chunk = Metaspace::get_space_list(mdtype)->get_new_chunk(chunk_word_size, 4780 get_space_manager(mdtype)->medium_chunk_bunch()); 4781 } 4782 4783 return chunk; 4784 } 4785 4786 void ClassLoaderMetaspace::initialize(Mutex* lock, Metaspace::MetaspaceType type) { 4787 Metaspace::verify_global_initialization(); 4788 4789 DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_metaspace_births)); 4790 4791 // Allocate SpaceManager for metadata objects. 4792 _vsm = new SpaceManager(Metaspace::NonClassType, type, lock); 4793 4794 if (Metaspace::using_class_space()) { 4795 // Allocate SpaceManager for classes. 4796 _class_vsm = new SpaceManager(Metaspace::ClassType, type, lock); 4797 } 4798 4799 MutexLockerEx cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag); 4800 4801 // Allocate chunk for metadata objects 4802 initialize_first_chunk(type, Metaspace::NonClassType); 4803 4804 // Allocate chunk for class metadata objects 4805 if (Metaspace::using_class_space()) { 4806 initialize_first_chunk(type, Metaspace::ClassType); 4807 } 4808 } 4809 4810 MetaWord* ClassLoaderMetaspace::allocate(size_t word_size, Metaspace::MetadataType mdtype) { 4811 Metaspace::assert_not_frozen(); 4812 4813 DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_allocs)); 4814 4815 // Don't use class_vsm() unless UseCompressedClassPointers is true. 4816 if (Metaspace::is_class_space_allocation(mdtype)) { 4817 return class_vsm()->allocate(word_size); 4818 } else { 4819 return vsm()->allocate(word_size); 4820 } 4821 } 4822 4823 MetaWord* ClassLoaderMetaspace::expand_and_allocate(size_t word_size, Metaspace::MetadataType mdtype) { 4824 Metaspace::assert_not_frozen(); 4825 size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord); 4826 assert(delta_bytes > 0, "Must be"); 4827 4828 size_t before = 0; 4829 size_t after = 0; 4830 MetaWord* res; 4831 bool incremented; 4832 4833 // Each thread increments the HWM at most once. Even if the thread fails to increment 4834 // the HWM, an allocation is still attempted. This is because another thread must then 4835 // have incremented the HWM and therefore the allocation might still succeed. 4836 do { 4837 incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before); 4838 res = allocate(word_size, mdtype); 4839 } while (!incremented && res == NULL); 4840 4841 if (incremented) { 4842 Metaspace::tracer()->report_gc_threshold(before, after, 4843 MetaspaceGCThresholdUpdater::ExpandAndAllocate); 4844 log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after); 4845 } 4846 4847 return res; 4848 } 4849 4850 size_t ClassLoaderMetaspace::allocated_blocks_bytes() const { 4851 return (vsm()->used_words() + 4852 (Metaspace::using_class_space() ? class_vsm()->used_words() : 0)) * BytesPerWord; 4853 } 4854 4855 size_t ClassLoaderMetaspace::allocated_chunks_bytes() const { 4856 return (vsm()->capacity_words() + 4857 (Metaspace::using_class_space() ? class_vsm()->capacity_words() : 0)) * BytesPerWord; 4858 } 4859 4860 void ClassLoaderMetaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) { 4861 Metaspace::assert_not_frozen(); 4862 assert(!SafepointSynchronize::is_at_safepoint() 4863 || Thread::current()->is_VM_thread(), "should be the VM thread"); 4864 4865 DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_external_deallocs)); 4866 4867 MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag); 4868 4869 if (is_class && Metaspace::using_class_space()) { 4870 class_vsm()->deallocate(ptr, word_size); 4871 } else { 4872 vsm()->deallocate(ptr, word_size); 4873 } 4874 } 4875 4876 size_t ClassLoaderMetaspace::class_chunk_size(size_t word_size) { 4877 assert(Metaspace::using_class_space(), "Has to use class space"); 4878 return class_vsm()->calc_chunk_size(word_size); 4879 } 4880 4881 void ClassLoaderMetaspace::print_on(outputStream* out) const { 4882 // Print both class virtual space counts and metaspace. 4883 if (Verbose) { 4884 vsm()->print_on(out); 4885 if (Metaspace::using_class_space()) { 4886 class_vsm()->print_on(out); 4887 } 4888 } 4889 } 4890 4891 void ClassLoaderMetaspace::verify() { 4892 vsm()->verify(); 4893 if (Metaspace::using_class_space()) { 4894 class_vsm()->verify(); 4895 } 4896 } 4897 4898 void ClassLoaderMetaspace::add_to_statistics_locked(ClassLoaderMetaspaceStatistics* out) const { 4899 assert_lock_strong(lock()); 4900 vsm()->add_to_statistics_locked(&out->nonclass_sm_stats()); 4901 if (Metaspace::using_class_space()) { 4902 class_vsm()->add_to_statistics_locked(&out->class_sm_stats()); 4903 } 4904 } 4905 4906 void ClassLoaderMetaspace::add_to_statistics(ClassLoaderMetaspaceStatistics* out) const { 4907 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 4908 add_to_statistics_locked(out); 4909 } 4910 4911 #ifdef ASSERT 4912 static void do_verify_chunk(Metachunk* chunk) { 4913 guarantee(chunk != NULL, "Sanity"); 4914 // Verify chunk itself; then verify that it is consistent with the 4915 // occupany map of its containing node. 4916 chunk->verify(); 4917 VirtualSpaceNode* const vsn = chunk->container(); 4918 OccupancyMap* const ocmap = vsn->occupancy_map(); 4919 ocmap->verify_for_chunk(chunk); 4920 } 4921 #endif 4922 4923 static void do_update_in_use_info_for_chunk(Metachunk* chunk, bool inuse) { 4924 chunk->set_is_tagged_free(!inuse); 4925 OccupancyMap* const ocmap = chunk->container()->occupancy_map(); 4926 ocmap->set_region_in_use((MetaWord*)chunk, chunk->word_size(), inuse); 4927 } 4928 4929 /////////////// Unit tests /////////////// 4930 4931 #ifndef PRODUCT 4932 4933 class TestMetaspaceUtilsTest : AllStatic { 4934 public: 4935 static void test_reserved() { 4936 size_t reserved = MetaspaceUtils::reserved_bytes(); 4937 4938 assert(reserved > 0, "assert"); 4939 4940 size_t committed = MetaspaceUtils::committed_bytes(); 4941 assert(committed <= reserved, "assert"); 4942 4943 size_t reserved_metadata = MetaspaceUtils::reserved_bytes(Metaspace::NonClassType); 4944 assert(reserved_metadata > 0, "assert"); 4945 assert(reserved_metadata <= reserved, "assert"); 4946 4947 if (UseCompressedClassPointers) { 4948 size_t reserved_class = MetaspaceUtils::reserved_bytes(Metaspace::ClassType); 4949 assert(reserved_class > 0, "assert"); 4950 assert(reserved_class < reserved, "assert"); 4951 } 4952 } 4953 4954 static void test_committed() { 4955 size_t committed = MetaspaceUtils::committed_bytes(); 4956 4957 assert(committed > 0, "assert"); 4958 4959 size_t reserved = MetaspaceUtils::reserved_bytes(); 4960 assert(committed <= reserved, "assert"); 4961 4962 size_t committed_metadata = MetaspaceUtils::committed_bytes(Metaspace::NonClassType); 4963 assert(committed_metadata > 0, "assert"); 4964 assert(committed_metadata <= committed, "assert"); 4965 4966 if (UseCompressedClassPointers) { 4967 size_t committed_class = MetaspaceUtils::committed_bytes(Metaspace::ClassType); 4968 assert(committed_class > 0, "assert"); 4969 assert(committed_class < committed, "assert"); 4970 } 4971 } 4972 4973 static void test_virtual_space_list_large_chunk() { 4974 VirtualSpaceList* vs_list = new VirtualSpaceList(os::vm_allocation_granularity()); 4975 MutexLockerEx cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag); 4976 // A size larger than VirtualSpaceSize (256k) and add one page to make it _not_ be 4977 // vm_allocation_granularity aligned on Windows. 4978 size_t large_size = (size_t)(2*256*K + (os::vm_page_size()/BytesPerWord)); 4979 large_size += (os::vm_page_size()/BytesPerWord); 4980 vs_list->get_new_chunk(large_size, 0); 4981 } 4982 4983 static void test() { 4984 test_reserved(); 4985 test_committed(); 4986 test_virtual_space_list_large_chunk(); 4987 } 4988 }; 4989 4990 void TestMetaspaceUtils_test() { 4991 TestMetaspaceUtilsTest::test(); 4992 } 4993 4994 class TestVirtualSpaceNodeTest { 4995 static void chunk_up(size_t words_left, size_t& num_medium_chunks, 4996 size_t& num_small_chunks, 4997 size_t& num_specialized_chunks) { 4998 num_medium_chunks = words_left / MediumChunk; 4999 words_left = words_left % MediumChunk; 5000 5001 num_small_chunks = words_left / SmallChunk; 5002 words_left = words_left % SmallChunk; 5003 // how many specialized chunks can we get? 5004 num_specialized_chunks = words_left / SpecializedChunk; 5005 assert(words_left % SpecializedChunk == 0, "should be nothing left"); 5006 } 5007 5008 public: 5009 static void test() { 5010 MutexLockerEx ml(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag); 5011 const size_t vsn_test_size_words = MediumChunk * 4; 5012 const size_t vsn_test_size_bytes = vsn_test_size_words * BytesPerWord; 5013 5014 // The chunk sizes must be multiples of eachother, or this will fail 5015 STATIC_ASSERT(MediumChunk % SmallChunk == 0); 5016 STATIC_ASSERT(SmallChunk % SpecializedChunk == 0); 5017 5018 { // No committed memory in VSN 5019 ChunkManager cm(false); 5020 VirtualSpaceNode vsn(false, vsn_test_size_bytes); 5021 vsn.initialize(); 5022 vsn.retire(&cm); 5023 assert(cm.sum_free_chunks_count() == 0, "did not commit any memory in the VSN"); 5024 } 5025 5026 { // All of VSN is committed, half is used by chunks 5027 ChunkManager cm(false); 5028 VirtualSpaceNode vsn(false, vsn_test_size_bytes); 5029 vsn.initialize(); 5030 vsn.expand_by(vsn_test_size_words, vsn_test_size_words); 5031 vsn.get_chunk_vs(MediumChunk); 5032 vsn.get_chunk_vs(MediumChunk); 5033 vsn.retire(&cm); 5034 assert(cm.sum_free_chunks_count() == 2, "should have been memory left for 2 medium chunks"); 5035 assert(cm.sum_free_chunks() == 2*MediumChunk, "sizes should add up"); 5036 } 5037 5038 const size_t page_chunks = 4 * (size_t)os::vm_page_size() / BytesPerWord; 5039 // This doesn't work for systems with vm_page_size >= 16K. 5040 if (page_chunks < MediumChunk) { 5041 // 4 pages of VSN is committed, some is used by chunks 5042 ChunkManager cm(false); 5043 VirtualSpaceNode vsn(false, vsn_test_size_bytes); 5044 5045 vsn.initialize(); 5046 vsn.expand_by(page_chunks, page_chunks); 5047 vsn.get_chunk_vs(SmallChunk); 5048 vsn.get_chunk_vs(SpecializedChunk); 5049 vsn.retire(&cm); 5050 5051 // committed - used = words left to retire 5052 const size_t words_left = page_chunks - SmallChunk - SpecializedChunk; 5053 5054 size_t num_medium_chunks, num_small_chunks, num_spec_chunks; 5055 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks); 5056 5057 assert(num_medium_chunks == 0, "should not get any medium chunks"); 5058 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks"); 5059 assert(cm.sum_free_chunks() == words_left, "sizes should add up"); 5060 } 5061 5062 { // Half of VSN is committed, a humongous chunk is used 5063 ChunkManager cm(false); 5064 VirtualSpaceNode vsn(false, vsn_test_size_bytes); 5065 vsn.initialize(); 5066 vsn.expand_by(MediumChunk * 2, MediumChunk * 2); 5067 vsn.get_chunk_vs(MediumChunk + SpecializedChunk); // Humongous chunks will be aligned up to MediumChunk + SpecializedChunk 5068 vsn.retire(&cm); 5069 5070 const size_t words_left = MediumChunk * 2 - (MediumChunk + SpecializedChunk); 5071 size_t num_medium_chunks, num_small_chunks, num_spec_chunks; 5072 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks); 5073 5074 assert(num_medium_chunks == 0, "should not get any medium chunks"); 5075 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks"); 5076 assert(cm.sum_free_chunks() == words_left, "sizes should add up"); 5077 } 5078 5079 } 5080 5081 #define assert_is_available_positive(word_size) \ 5082 assert(vsn.is_available(word_size), \ 5083 #word_size ": " PTR_FORMAT " bytes were not available in " \ 5084 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \ 5085 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())); 5086 5087 #define assert_is_available_negative(word_size) \ 5088 assert(!vsn.is_available(word_size), \ 5089 #word_size ": " PTR_FORMAT " bytes should not be available in " \ 5090 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \ 5091 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())); 5092 5093 static void test_is_available_positive() { 5094 // Reserve some memory. 5095 VirtualSpaceNode vsn(false, os::vm_allocation_granularity()); 5096 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 5097 5098 // Commit some memory. 5099 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 5100 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 5101 assert(expanded, "Failed to commit"); 5102 5103 // Check that is_available accepts the committed size. 5104 assert_is_available_positive(commit_word_size); 5105 5106 // Check that is_available accepts half the committed size. 5107 size_t expand_word_size = commit_word_size / 2; 5108 assert_is_available_positive(expand_word_size); 5109 } 5110 5111 static void test_is_available_negative() { 5112 // Reserve some memory. 5113 VirtualSpaceNode vsn(false, os::vm_allocation_granularity()); 5114 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 5115 5116 // Commit some memory. 5117 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 5118 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 5119 assert(expanded, "Failed to commit"); 5120 5121 // Check that is_available doesn't accept a too large size. 5122 size_t two_times_commit_word_size = commit_word_size * 2; 5123 assert_is_available_negative(two_times_commit_word_size); 5124 } 5125 5126 static void test_is_available_overflow() { 5127 // Reserve some memory. 5128 VirtualSpaceNode vsn(false, os::vm_allocation_granularity()); 5129 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 5130 5131 // Commit some memory. 5132 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 5133 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 5134 assert(expanded, "Failed to commit"); 5135 5136 // Calculate a size that will overflow the virtual space size. 5137 void* virtual_space_max = (void*)(uintptr_t)-1; 5138 size_t bottom_to_max = pointer_delta(virtual_space_max, vsn.bottom(), 1); 5139 size_t overflow_size = bottom_to_max + BytesPerWord; 5140 size_t overflow_word_size = overflow_size / BytesPerWord; 5141 5142 // Check that is_available can handle the overflow. 5143 assert_is_available_negative(overflow_word_size); 5144 } 5145 5146 static void test_is_available() { 5147 TestVirtualSpaceNodeTest::test_is_available_positive(); 5148 TestVirtualSpaceNodeTest::test_is_available_negative(); 5149 TestVirtualSpaceNodeTest::test_is_available_overflow(); 5150 } 5151 }; 5152 5153 // The following test is placed here instead of a gtest / unittest file 5154 // because the ChunkManager class is only available in this file. 5155 void ChunkManager_test_list_index() { 5156 { 5157 // Test previous bug where a query for a humongous class metachunk, 5158 // incorrectly matched the non-class medium metachunk size. 5159 { 5160 ChunkManager manager(true); 5161 5162 assert(MediumChunk > ClassMediumChunk, "Precondition for test"); 5163 5164 ChunkIndex index = manager.list_index(MediumChunk); 5165 5166 assert(index == HumongousIndex, 5167 "Requested size is larger than ClassMediumChunk," 5168 " so should return HumongousIndex. Got index: %d", (int)index); 5169 } 5170 5171 // Check the specified sizes as well. 5172 { 5173 ChunkManager manager(true); 5174 assert(manager.list_index(ClassSpecializedChunk) == SpecializedIndex, "sanity"); 5175 assert(manager.list_index(ClassSmallChunk) == SmallIndex, "sanity"); 5176 assert(manager.list_index(ClassMediumChunk) == MediumIndex, "sanity"); 5177 assert(manager.list_index(ClassMediumChunk + ClassSpecializedChunk) == HumongousIndex, "sanity"); 5178 } 5179 { 5180 ChunkManager manager(false); 5181 assert(manager.list_index(SpecializedChunk) == SpecializedIndex, "sanity"); 5182 assert(manager.list_index(SmallChunk) == SmallIndex, "sanity"); 5183 assert(manager.list_index(MediumChunk) == MediumIndex, "sanity"); 5184 assert(manager.list_index(MediumChunk + SpecializedChunk) == HumongousIndex, "sanity"); 5185 } 5186 5187 } 5188 5189 } 5190 5191 #endif // !PRODUCT 5192 5193 #ifdef ASSERT 5194 5195 // The following test is placed here instead of a gtest / unittest file 5196 // because the ChunkManager class is only available in this file. 5197 class SpaceManagerTest : AllStatic { 5198 friend void SpaceManager_test_adjust_initial_chunk_size(); 5199 5200 static void test_adjust_initial_chunk_size(bool is_class) { 5201 const size_t smallest = SpaceManager::smallest_chunk_size(is_class); 5202 const size_t normal = SpaceManager::small_chunk_size(is_class); 5203 const size_t medium = SpaceManager::medium_chunk_size(is_class); 5204 5205 #define test_adjust_initial_chunk_size(value, expected, is_class_value) \ 5206 do { \ 5207 size_t v = value; \ 5208 size_t e = expected; \ 5209 assert(SpaceManager::adjust_initial_chunk_size(v, (is_class_value)) == e, \ 5210 "Expected: " SIZE_FORMAT " got: " SIZE_FORMAT, e, v); \ 5211 } while (0) 5212 5213 // Smallest (specialized) 5214 test_adjust_initial_chunk_size(1, smallest, is_class); 5215 test_adjust_initial_chunk_size(smallest - 1, smallest, is_class); 5216 test_adjust_initial_chunk_size(smallest, smallest, is_class); 5217 5218 // Small 5219 test_adjust_initial_chunk_size(smallest + 1, normal, is_class); 5220 test_adjust_initial_chunk_size(normal - 1, normal, is_class); 5221 test_adjust_initial_chunk_size(normal, normal, is_class); 5222 5223 // Medium 5224 test_adjust_initial_chunk_size(normal + 1, medium, is_class); 5225 test_adjust_initial_chunk_size(medium - 1, medium, is_class); 5226 test_adjust_initial_chunk_size(medium, medium, is_class); 5227 5228 // Humongous 5229 test_adjust_initial_chunk_size(medium + 1, medium + 1, is_class); 5230 5231 #undef test_adjust_initial_chunk_size 5232 } 5233 5234 static void test_adjust_initial_chunk_size() { 5235 test_adjust_initial_chunk_size(false); 5236 test_adjust_initial_chunk_size(true); 5237 } 5238 }; 5239 5240 void SpaceManager_test_adjust_initial_chunk_size() { 5241 SpaceManagerTest::test_adjust_initial_chunk_size(); 5242 } 5243 5244 #endif // ASSERT 5245 5246 struct chunkmanager_statistics_t { 5247 int num_specialized_chunks; 5248 int num_small_chunks; 5249 int num_medium_chunks; 5250 int num_humongous_chunks; 5251 }; 5252 5253 extern void test_metaspace_retrieve_chunkmanager_statistics(Metaspace::MetadataType mdType, chunkmanager_statistics_t* out) { 5254 ChunkManager* const chunk_manager = Metaspace::get_chunk_manager(mdType); 5255 ChunkManagerStatistics stat; 5256 chunk_manager->collect_statistics(&stat); 5257 out->num_specialized_chunks = (int)stat.chunk_stats(SpecializedIndex).num(); 5258 out->num_small_chunks = (int)stat.chunk_stats(SmallIndex).num(); 5259 out->num_medium_chunks = (int)stat.chunk_stats(MediumIndex).num(); 5260 out->num_humongous_chunks = (int)stat.chunk_stats(HumongousIndex).num(); 5261 } 5262 5263 struct chunk_geometry_t { 5264 size_t specialized_chunk_word_size; 5265 size_t small_chunk_word_size; 5266 size_t medium_chunk_word_size; 5267 }; 5268 5269 extern void test_metaspace_retrieve_chunk_geometry(Metaspace::MetadataType mdType, chunk_geometry_t* out) { 5270 if (mdType == Metaspace::NonClassType) { 5271 out->specialized_chunk_word_size = SpecializedChunk; 5272 out->small_chunk_word_size = SmallChunk; 5273 out->medium_chunk_word_size = MediumChunk; 5274 } else { 5275 out->specialized_chunk_word_size = ClassSpecializedChunk; 5276 out->small_chunk_word_size = ClassSmallChunk; 5277 out->medium_chunk_word_size = ClassMediumChunk; 5278 } 5279 }