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/metaspaceGCThresholdUpdater.hpp" 37 #include "memory/metaspaceShared.hpp" 38 #include "memory/metaspaceTracer.hpp" 39 #include "memory/resourceArea.hpp" 40 #include "memory/universe.hpp" 41 #include "runtime/atomic.hpp" 42 #include "runtime/globals.hpp" 43 #include "runtime/init.hpp" 44 #include "runtime/java.hpp" 45 #include "runtime/mutex.hpp" 46 #include "runtime/orderAccess.inline.hpp" 47 #include "services/memTracker.hpp" 48 #include "services/memoryService.hpp" 49 #include "utilities/align.hpp" 50 #include "utilities/copy.hpp" 51 #include "utilities/debug.hpp" 52 #include "utilities/macros.hpp" 53 54 typedef BinaryTreeDictionary<Metablock, FreeList<Metablock> > BlockTreeDictionary; 55 typedef BinaryTreeDictionary<Metachunk, FreeList<Metachunk> > ChunkTreeDictionary; 56 57 // Helper function that does a bunch of checks for a chunk. 58 DEBUG_ONLY(static void do_verify_chunk(Metachunk* chunk);) 59 60 // Given a Metachunk, update its in-use information (both in the 61 // chunk and the occupancy map). 62 static void do_update_in_use_info_for_chunk(Metachunk* chunk, bool inuse); 63 64 size_t const allocation_from_dictionary_limit = 4 * K; 65 66 MetaWord* last_allocated = 0; 67 68 size_t Metaspace::_compressed_class_space_size; 69 const MetaspaceTracer* Metaspace::_tracer = NULL; 70 71 DEBUG_ONLY(bool Metaspace::_frozen = false;) 72 73 enum ChunkSizes { // in words. 74 ClassSpecializedChunk = 128, 75 SpecializedChunk = 128, 76 ClassSmallChunk = 256, 77 SmallChunk = 512, 78 ClassMediumChunk = 4 * K, 79 MediumChunk = 8 * K 80 }; 81 82 // Returns size of this chunk type. 83 size_t get_size_for_nonhumongous_chunktype(ChunkIndex chunktype, bool is_class) { 84 assert(is_valid_nonhumongous_chunktype(chunktype), "invalid chunk type."); 85 size_t size = 0; 86 if (is_class) { 87 switch(chunktype) { 88 case SpecializedIndex: size = ClassSpecializedChunk; break; 89 case SmallIndex: size = ClassSmallChunk; break; 90 case MediumIndex: size = ClassMediumChunk; break; 91 default: 92 ShouldNotReachHere(); 93 } 94 } else { 95 switch(chunktype) { 96 case SpecializedIndex: size = SpecializedChunk; break; 97 case SmallIndex: size = SmallChunk; break; 98 case MediumIndex: size = MediumChunk; break; 99 default: 100 ShouldNotReachHere(); 101 } 102 } 103 return size; 104 } 105 106 ChunkIndex get_chunk_type_by_size(size_t size, bool is_class) { 107 if (is_class) { 108 if (size == ClassSpecializedChunk) { 109 return SpecializedIndex; 110 } else if (size == ClassSmallChunk) { 111 return SmallIndex; 112 } else if (size == ClassMediumChunk) { 113 return MediumIndex; 114 } else if (size > ClassMediumChunk) { 115 // A valid humongous chunk size is a multiple of the smallest chunk size. 116 assert(is_aligned(size, ClassSpecializedChunk), "Invalid chunk size"); 117 return HumongousIndex; 118 } 119 } else { 120 if (size == SpecializedChunk) { 121 return SpecializedIndex; 122 } else if (size == SmallChunk) { 123 return SmallIndex; 124 } else if (size == MediumChunk) { 125 return MediumIndex; 126 } else if (size > MediumChunk) { 127 // A valid humongous chunk size is a multiple of the smallest chunk size. 128 assert(is_aligned(size, SpecializedChunk), "Invalid chunk size"); 129 return HumongousIndex; 130 } 131 } 132 ShouldNotReachHere(); 133 return (ChunkIndex)-1; 134 } 135 136 137 static ChunkIndex next_chunk_index(ChunkIndex i) { 138 assert(i < NumberOfInUseLists, "Out of bound"); 139 return (ChunkIndex) (i+1); 140 } 141 142 static ChunkIndex prev_chunk_index(ChunkIndex i) { 143 assert(i > ZeroIndex, "Out of bound"); 144 return (ChunkIndex) (i-1); 145 } 146 147 static const char* scale_unit(size_t scale) { 148 switch(scale) { 149 case 1: return "BYTES"; 150 case K: return "KB"; 151 case M: return "MB"; 152 case G: return "GB"; 153 default: 154 ShouldNotReachHere(); 155 return NULL; 156 } 157 } 158 159 volatile intptr_t MetaspaceGC::_capacity_until_GC = 0; 160 uint MetaspaceGC::_shrink_factor = 0; 161 bool MetaspaceGC::_should_concurrent_collect = false; 162 163 typedef class FreeList<Metachunk> ChunkList; 164 165 // Manages the global free lists of chunks. 166 class ChunkManager : public CHeapObj<mtInternal> { 167 friend class TestVirtualSpaceNodeTest; 168 169 // Free list of chunks of different sizes. 170 // SpecializedChunk 171 // SmallChunk 172 // MediumChunk 173 ChunkList _free_chunks[NumberOfFreeLists]; 174 175 // Whether or not this is the class chunkmanager. 176 const bool _is_class; 177 178 // Return non-humongous chunk list by its index. 179 ChunkList* free_chunks(ChunkIndex index); 180 181 // Returns non-humongous chunk list for the given chunk word size. 182 ChunkList* find_free_chunks_list(size_t word_size); 183 184 // HumongousChunk 185 ChunkTreeDictionary _humongous_dictionary; 186 187 // Returns the humongous chunk dictionary. 188 ChunkTreeDictionary* humongous_dictionary() { 189 return &_humongous_dictionary; 190 } 191 192 // Size, in metaspace words, of all chunks managed by this ChunkManager 193 size_t _free_chunks_total; 194 // Number of chunks in this ChunkManager 195 size_t _free_chunks_count; 196 197 // Update counters after a chunk was added or removed removed. 198 void account_for_added_chunk(const Metachunk* c); 199 void account_for_removed_chunk(const Metachunk* c); 200 201 // Debug support 202 203 size_t sum_free_chunks(); 204 size_t sum_free_chunks_count(); 205 206 void locked_verify_free_chunks_total(); 207 void slow_locked_verify_free_chunks_total() { 208 if (VerifyMetaspace) { 209 locked_verify_free_chunks_total(); 210 } 211 } 212 void locked_verify_free_chunks_count(); 213 void slow_locked_verify_free_chunks_count() { 214 if (VerifyMetaspace) { 215 locked_verify_free_chunks_count(); 216 } 217 } 218 void verify_free_chunks_count(); 219 220 // Given a pointer to a chunk, attempts to merge it with neighboring 221 // free chunks to form a bigger chunk. Returns true if successful. 222 bool attempt_to_coalesce_around_chunk(Metachunk* chunk, ChunkIndex target_chunk_type); 223 224 // Helper for chunk merging: 225 // Given an address range with 1-n chunks which are all supposed to be 226 // free and hence currently managed by this ChunkManager, remove them 227 // from this ChunkManager and mark them as invalid. 228 // - This does not correct the occupancy map. 229 // - This does not adjust the counters in ChunkManager. 230 // - Does not adjust container count counter in containing VirtualSpaceNode. 231 // Returns number of chunks removed. 232 int remove_chunks_in_area(MetaWord* p, size_t word_size); 233 234 // Helper for chunk splitting: given a target chunk size and a larger free chunk, 235 // split up the larger chunk into n smaller chunks, at least one of which should be 236 // the target chunk of target chunk size. The smaller chunks, including the target 237 // chunk, are returned to the freelist. The pointer to the target chunk is returned. 238 // Note that this chunk is supposed to be removed from the freelist right away. 239 Metachunk* split_chunk(size_t target_chunk_word_size, Metachunk* chunk); 240 241 public: 242 243 struct ChunkManagerStatistics { 244 size_t num_by_type[NumberOfFreeLists]; 245 size_t single_size_by_type[NumberOfFreeLists]; 246 size_t total_size_by_type[NumberOfFreeLists]; 247 size_t num_humongous_chunks; 248 size_t total_size_humongous_chunks; 249 }; 250 251 void locked_get_statistics(ChunkManagerStatistics* stat) const; 252 void get_statistics(ChunkManagerStatistics* stat) const; 253 static void print_statistics(const ChunkManagerStatistics* stat, outputStream* out, size_t scale); 254 255 256 ChunkManager(bool is_class) 257 : _is_class(is_class), _free_chunks_total(0), _free_chunks_count(0) { 258 _free_chunks[SpecializedIndex].set_size(get_size_for_nonhumongous_chunktype(SpecializedIndex, is_class)); 259 _free_chunks[SmallIndex].set_size(get_size_for_nonhumongous_chunktype(SmallIndex, is_class)); 260 _free_chunks[MediumIndex].set_size(get_size_for_nonhumongous_chunktype(MediumIndex, is_class)); 261 } 262 263 // Add or delete (return) a chunk to the global freelist. 264 Metachunk* chunk_freelist_allocate(size_t word_size); 265 266 // Map a size to a list index assuming that there are lists 267 // for special, small, medium, and humongous chunks. 268 ChunkIndex list_index(size_t size); 269 270 // Map a given index to the chunk size. 271 size_t size_by_index(ChunkIndex index) const; 272 273 bool is_class() const { return _is_class; } 274 275 // Convenience accessors. 276 size_t medium_chunk_word_size() const { return size_by_index(MediumIndex); } 277 size_t small_chunk_word_size() const { return size_by_index(SmallIndex); } 278 size_t specialized_chunk_word_size() const { return size_by_index(SpecializedIndex); } 279 280 // Take a chunk from the ChunkManager. The chunk is expected to be in 281 // the chunk manager (the freelist if non-humongous, the dictionary if 282 // humongous). 283 void remove_chunk(Metachunk* chunk); 284 285 // Return a single chunk of type index to the ChunkManager. 286 void return_single_chunk(ChunkIndex index, Metachunk* chunk); 287 288 // Add the simple linked list of chunks to the freelist of chunks 289 // of type index. 290 void return_chunk_list(ChunkIndex index, Metachunk* chunk); 291 292 // Total of the space in the free chunks list 293 size_t free_chunks_total_words(); 294 size_t free_chunks_total_bytes(); 295 296 // Number of chunks in the free chunks list 297 size_t free_chunks_count(); 298 299 // Remove from a list by size. Selects list based on size of chunk. 300 Metachunk* free_chunks_get(size_t chunk_word_size); 301 302 #define index_bounds_check(index) \ 303 assert(is_valid_chunktype(index), "Bad index: %d", (int) index) 304 305 size_t num_free_chunks(ChunkIndex index) const { 306 index_bounds_check(index); 307 308 if (index == HumongousIndex) { 309 return _humongous_dictionary.total_free_blocks(); 310 } 311 312 ssize_t count = _free_chunks[index].count(); 313 return count == -1 ? 0 : (size_t) count; 314 } 315 316 size_t size_free_chunks_in_bytes(ChunkIndex index) const { 317 index_bounds_check(index); 318 319 size_t word_size = 0; 320 if (index == HumongousIndex) { 321 word_size = _humongous_dictionary.total_size(); 322 } else { 323 const size_t size_per_chunk_in_words = _free_chunks[index].size(); 324 word_size = size_per_chunk_in_words * num_free_chunks(index); 325 } 326 327 return word_size * BytesPerWord; 328 } 329 330 MetaspaceChunkFreeListSummary chunk_free_list_summary() const { 331 return MetaspaceChunkFreeListSummary(num_free_chunks(SpecializedIndex), 332 num_free_chunks(SmallIndex), 333 num_free_chunks(MediumIndex), 334 num_free_chunks(HumongousIndex), 335 size_free_chunks_in_bytes(SpecializedIndex), 336 size_free_chunks_in_bytes(SmallIndex), 337 size_free_chunks_in_bytes(MediumIndex), 338 size_free_chunks_in_bytes(HumongousIndex)); 339 } 340 341 // Debug support 342 void verify(); 343 void slow_verify() { 344 if (VerifyMetaspace) { 345 verify(); 346 } 347 } 348 void locked_verify(); 349 void slow_locked_verify() { 350 if (VerifyMetaspace) { 351 locked_verify(); 352 } 353 } 354 void verify_free_chunks_total(); 355 356 void locked_print_free_chunks(outputStream* st); 357 void locked_print_sum_free_chunks(outputStream* st); 358 359 void print_on(outputStream* st) const; 360 361 // Prints composition for both non-class and (if available) 362 // class chunk manager. 363 static void print_all_chunkmanagers(outputStream* out, size_t scale = 1); 364 }; 365 366 class SmallBlocks : public CHeapObj<mtClass> { 367 const static uint _small_block_max_size = sizeof(TreeChunk<Metablock, FreeList<Metablock> >)/HeapWordSize; 368 const static uint _small_block_min_size = sizeof(Metablock)/HeapWordSize; 369 370 private: 371 FreeList<Metablock> _small_lists[_small_block_max_size - _small_block_min_size]; 372 373 FreeList<Metablock>& list_at(size_t word_size) { 374 assert(word_size >= _small_block_min_size, "There are no metaspace objects less than %u words", _small_block_min_size); 375 return _small_lists[word_size - _small_block_min_size]; 376 } 377 378 public: 379 SmallBlocks() { 380 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 381 uint k = i - _small_block_min_size; 382 _small_lists[k].set_size(i); 383 } 384 } 385 386 size_t total_size() const { 387 size_t result = 0; 388 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 389 uint k = i - _small_block_min_size; 390 result = result + _small_lists[k].count() * _small_lists[k].size(); 391 } 392 return result; 393 } 394 395 static uint small_block_max_size() { return _small_block_max_size; } 396 static uint small_block_min_size() { return _small_block_min_size; } 397 398 MetaWord* get_block(size_t word_size) { 399 if (list_at(word_size).count() > 0) { 400 MetaWord* new_block = (MetaWord*) list_at(word_size).get_chunk_at_head(); 401 return new_block; 402 } else { 403 return NULL; 404 } 405 } 406 void return_block(Metablock* free_chunk, size_t word_size) { 407 list_at(word_size).return_chunk_at_head(free_chunk, false); 408 assert(list_at(word_size).count() > 0, "Should have a chunk"); 409 } 410 411 void print_on(outputStream* st) const { 412 st->print_cr("SmallBlocks:"); 413 for (uint i = _small_block_min_size; i < _small_block_max_size; i++) { 414 uint k = i - _small_block_min_size; 415 st->print_cr("small_lists size " SIZE_FORMAT " count " SIZE_FORMAT, _small_lists[k].size(), _small_lists[k].count()); 416 } 417 } 418 }; 419 420 // Used to manage the free list of Metablocks (a block corresponds 421 // to the allocation of a quantum of metadata). 422 class BlockFreelist : public CHeapObj<mtClass> { 423 BlockTreeDictionary* const _dictionary; 424 SmallBlocks* _small_blocks; 425 426 // Only allocate and split from freelist if the size of the allocation 427 // is at least 1/4th the size of the available block. 428 const static int WasteMultiplier = 4; 429 430 // Accessors 431 BlockTreeDictionary* dictionary() const { return _dictionary; } 432 SmallBlocks* small_blocks() { 433 if (_small_blocks == NULL) { 434 _small_blocks = new SmallBlocks(); 435 } 436 return _small_blocks; 437 } 438 439 public: 440 BlockFreelist(); 441 ~BlockFreelist(); 442 443 // Get and return a block to the free list 444 MetaWord* get_block(size_t word_size); 445 void return_block(MetaWord* p, size_t word_size); 446 447 size_t total_size() const { 448 size_t result = dictionary()->total_size(); 449 if (_small_blocks != NULL) { 450 result = result + _small_blocks->total_size(); 451 } 452 return result; 453 } 454 455 static size_t min_dictionary_size() { return TreeChunk<Metablock, FreeList<Metablock> >::min_size(); } 456 void print_on(outputStream* st) const; 457 }; 458 459 // Helper for Occupancy Bitmap. A type trait to give an all-bits-are-one-unsigned constant. 460 template <typename T> struct all_ones { static const T value; }; 461 template <> struct all_ones <uint64_t> { static const uint64_t value = 0xFFFFFFFFFFFFFFFFULL; }; 462 template <> struct all_ones <uint32_t> { static const uint32_t value = 0xFFFFFFFF; }; 463 464 // The OccupancyMap is a bitmap which, for a given VirtualSpaceNode, 465 // keeps information about 466 // - where a chunk starts 467 // - whether a chunk is in-use or free 468 // A bit in this bitmap represents one range of memory in the smallest 469 // chunk size (SpecializedChunk or ClassSpecializedChunk). 470 class OccupancyMap : public CHeapObj<mtInternal> { 471 472 // The address range this map covers. 473 const MetaWord* const _reference_address; 474 const size_t _word_size; 475 476 // The word size of a specialized chunk, aka the number of words one 477 // bit in this map represents. 478 const size_t _smallest_chunk_word_size; 479 480 // map data 481 // Data are organized in two bit layers: 482 // The first layer is the chunk-start-map. Here, a bit is set to mark 483 // the corresponding region as the head of a chunk. 484 // The second layer is the in-use-map. Here, a set bit indicates that 485 // the corresponding belongs to a chunk which is in use. 486 uint8_t* _map[2]; 487 488 enum { layer_chunk_start_map = 0, layer_in_use_map = 1 }; 489 490 // length, in bytes, of bitmap data 491 size_t _map_size; 492 493 // Returns true if bit at position pos at bit-layer layer is set. 494 bool get_bit_at_position(unsigned pos, unsigned layer) const { 495 assert(layer == 0 || layer == 1, "Invalid layer %d", layer); 496 const unsigned byteoffset = pos / 8; 497 assert(byteoffset < _map_size, 498 "invalid byte offset (%u), map size is " SIZE_FORMAT ".", byteoffset, _map_size); 499 const unsigned mask = 1 << (pos % 8); 500 return (_map[layer][byteoffset] & mask) > 0; 501 } 502 503 // Changes bit at position pos at bit-layer layer to value v. 504 void set_bit_at_position(unsigned pos, unsigned layer, bool v) { 505 assert(layer == 0 || layer == 1, "Invalid layer %d", layer); 506 const unsigned byteoffset = pos / 8; 507 assert(byteoffset < _map_size, 508 "invalid byte offset (%u), map size is " SIZE_FORMAT ".", byteoffset, _map_size); 509 const unsigned mask = 1 << (pos % 8); 510 if (v) { 511 _map[layer][byteoffset] |= mask; 512 } else { 513 _map[layer][byteoffset] &= ~mask; 514 } 515 } 516 517 // Optimized case of is_any_bit_set_in_region for 32/64bit aligned access: 518 // pos is 32/64 aligned and num_bits is 32/64. 519 // This is the typical case when coalescing to medium chunks, whose size is 520 // 32 or 64 times the specialized chunk size (depending on class or non class 521 // case), so they occupy 64 bits which should be 64bit aligned, because 522 // chunks are chunk-size aligned. 523 template <typename T> 524 bool is_any_bit_set_in_region_3264(unsigned pos, unsigned num_bits, unsigned layer) const { 525 assert(_map_size > 0, "not initialized"); 526 assert(layer == 0 || layer == 1, "Invalid layer %d.", layer); 527 assert(pos % (sizeof(T) * 8) == 0, "Bit position must be aligned (%u).", pos); 528 assert(num_bits == (sizeof(T) * 8), "Number of bits incorrect (%u).", num_bits); 529 const size_t byteoffset = pos / 8; 530 assert(byteoffset <= (_map_size - sizeof(T)), 531 "Invalid byte offset (" SIZE_FORMAT "), map size is " SIZE_FORMAT ".", byteoffset, _map_size); 532 const T w = *(T*)(_map[layer] + byteoffset); 533 return w > 0 ? true : false; 534 } 535 536 // Returns true if any bit in region [pos1, pos1 + num_bits) is set in bit-layer layer. 537 bool is_any_bit_set_in_region(unsigned pos, unsigned num_bits, unsigned layer) const { 538 if (pos % 32 == 0 && num_bits == 32) { 539 return is_any_bit_set_in_region_3264<uint32_t>(pos, num_bits, layer); 540 } else if (pos % 64 == 0 && num_bits == 64) { 541 return is_any_bit_set_in_region_3264<uint64_t>(pos, num_bits, layer); 542 } else { 543 for (unsigned n = 0; n < num_bits; n ++) { 544 if (get_bit_at_position(pos + n, layer)) { 545 return true; 546 } 547 } 548 } 549 return false; 550 } 551 552 // Returns true if any bit in region [p, p+word_size) is set in bit-layer layer. 553 bool is_any_bit_set_in_region(MetaWord* p, size_t word_size, unsigned layer) const { 554 assert(word_size % _smallest_chunk_word_size == 0, 555 "Region size " SIZE_FORMAT " not a multiple of smallest chunk size.", word_size); 556 const unsigned pos = get_bitpos_for_address(p); 557 const unsigned num_bits = (unsigned) (word_size / _smallest_chunk_word_size); 558 return is_any_bit_set_in_region(pos, num_bits, layer); 559 } 560 561 // Optimized case of set_bits_of_region for 32/64bit aligned access: 562 // pos is 32/64 aligned and num_bits is 32/64. 563 // This is the typical case when coalescing to medium chunks, whose size 564 // is 32 or 64 times the specialized chunk size (depending on class or non 565 // class case), so they occupy 64 bits which should be 64bit aligned, 566 // because chunks are chunk-size aligned. 567 template <typename T> 568 void set_bits_of_region_T(unsigned pos, unsigned num_bits, unsigned layer, bool v) { 569 assert(pos % (sizeof(T) * 8) == 0, "Bit position must be aligned to %u (%u).", 570 (unsigned)(sizeof(T) * 8), pos); 571 assert(num_bits == (sizeof(T) * 8), "Number of bits incorrect (%u), expected %u.", 572 num_bits, (unsigned)(sizeof(T) * 8)); 573 const size_t byteoffset = pos / 8; 574 assert(byteoffset <= (_map_size - sizeof(T)), 575 "invalid byte offset (" SIZE_FORMAT "), map size is " SIZE_FORMAT ".", byteoffset, _map_size); 576 T* const pw = (T*)(_map[layer] + byteoffset); 577 *pw = v ? all_ones<T>::value : (T) 0; 578 } 579 580 // Set all bits in a region starting at pos to a value. 581 void set_bits_of_region(unsigned pos, unsigned num_bits, unsigned layer, bool v) { 582 assert(_map_size > 0, "not initialized"); 583 assert(layer == 0 || layer == 1, "Invalid layer %d.", layer); 584 if (pos % 32 == 0 && num_bits == 32) { 585 set_bits_of_region_T<uint32_t>(pos, num_bits, layer, v); 586 } else if (pos % 64 == 0 && num_bits == 64) { 587 set_bits_of_region_T<uint64_t>(pos, num_bits, layer, v); 588 } else { 589 for (unsigned n = 0; n < num_bits; n ++) { 590 set_bit_at_position(pos + n, layer, v); 591 } 592 } 593 } 594 595 // Helper: sets all bits in a region [p, p+word_size). 596 void set_bits_of_region(MetaWord* p, size_t word_size, unsigned layer, bool v) { 597 assert(word_size % _smallest_chunk_word_size == 0, 598 "Region size " SIZE_FORMAT " not a multiple of smallest chunk size.", word_size); 599 const unsigned pos = get_bitpos_for_address(p); 600 const unsigned num_bits = (unsigned) (word_size / _smallest_chunk_word_size); 601 set_bits_of_region(pos, num_bits, layer, v); 602 } 603 604 // Helper: given an address, return the bit position representing that address. 605 unsigned get_bitpos_for_address(const MetaWord* p) const { 606 assert(_reference_address != NULL, "not initialized"); 607 assert(p >= _reference_address && p < _reference_address + _word_size, 608 "Address %p out of range for occupancy map [%p..%p).", 609 p, _reference_address, _reference_address + _word_size); 610 assert(is_aligned(p, _smallest_chunk_word_size * sizeof(MetaWord)), 611 "Address not aligned (%p).", p); 612 const ptrdiff_t d = (p - _reference_address) / _smallest_chunk_word_size; 613 assert(d >= 0 && (size_t)d < _map_size * 8, "Sanity."); 614 return (unsigned) d; 615 } 616 617 public: 618 619 OccupancyMap(const MetaWord* reference_address, size_t word_size, size_t smallest_chunk_word_size) : 620 _reference_address(reference_address), _word_size(word_size), 621 _smallest_chunk_word_size(smallest_chunk_word_size) { 622 assert(reference_address != NULL, "invalid reference address"); 623 assert(is_aligned(reference_address, smallest_chunk_word_size), 624 "Reference address not aligned to smallest chunk size."); 625 assert(is_aligned(word_size, smallest_chunk_word_size), 626 "Word_size shall be a multiple of the smallest chunk size."); 627 // Calculate bitmap size: one bit per smallest_chunk_word_size'd area. 628 size_t num_bits = word_size / smallest_chunk_word_size; 629 _map_size = (num_bits + 7) / 8; 630 assert(_map_size * 8 >= num_bits, "sanity"); 631 _map[0] = (uint8_t*) os::malloc(_map_size, mtInternal); 632 _map[1] = (uint8_t*) os::malloc(_map_size, mtInternal); 633 assert(_map[0] != NULL && _map[1] != NULL, "Occupancy Map: allocation failed."); 634 memset(_map[1], 0, _map_size); 635 memset(_map[0], 0, _map_size); 636 // Sanity test: the first respectively last possible chunk start address in 637 // the covered range shall map to the first and last bit in the bitmap. 638 assert(get_bitpos_for_address(reference_address) == 0, 639 "First chunk address in range must map to fist bit in bitmap."); 640 assert(get_bitpos_for_address(reference_address + word_size - smallest_chunk_word_size) == num_bits - 1, 641 "Last chunk address in range must map to last bit in bitmap."); 642 } 643 644 ~OccupancyMap() { 645 os::free(_map[0]); 646 os::free(_map[1]); 647 } 648 649 // Returns true if at address x a chunk is starting. 650 bool chunk_starts_at_address(MetaWord* p) const { 651 const unsigned pos = get_bitpos_for_address(p); 652 return get_bit_at_position(pos, layer_chunk_start_map); 653 } 654 655 void set_chunk_starts_at_address(MetaWord* p, bool v) { 656 const unsigned pos = get_bitpos_for_address(p); 657 set_bit_at_position(pos, layer_chunk_start_map, v); 658 } 659 660 // Removes all chunk-start-bits inside a region, typically as a 661 // result of a chunk merge. 662 void wipe_chunk_start_bits_in_region(MetaWord* p, size_t word_size) { 663 set_bits_of_region(p, word_size, layer_chunk_start_map, false); 664 } 665 666 // Returns true if there are life (in use) chunks in the region limited 667 // by [p, p+word_size). 668 bool is_region_in_use(MetaWord* p, size_t word_size) const { 669 return is_any_bit_set_in_region(p, word_size, layer_in_use_map); 670 } 671 672 // Marks the region starting at p with the size word_size as in use 673 // or free, depending on v. 674 void set_region_in_use(MetaWord* p, size_t word_size, bool v) { 675 set_bits_of_region(p, word_size, layer_in_use_map, v); 676 } 677 678 #ifdef ASSERT 679 // Verify occupancy map for the address range [from, to). 680 // We need to tell it the address range, because the memory the 681 // occupancy map is covering may not be fully comitted yet. 682 void verify(MetaWord* from, MetaWord* to) { 683 Metachunk* chunk = NULL; 684 int nth_bit_for_chunk = 0; 685 MetaWord* chunk_end = NULL; 686 for (MetaWord* p = from; p < to; p += _smallest_chunk_word_size) { 687 const unsigned pos = get_bitpos_for_address(p); 688 // Check the chunk-starts-info: 689 if (get_bit_at_position(pos, layer_chunk_start_map)) { 690 // Chunk start marked in bitmap. 691 chunk = (Metachunk*) p; 692 if (chunk_end != NULL) { 693 assert(chunk_end == p, "Unexpected chunk start found at %p (expected " 694 "the next chunk to start at %p).", p, chunk_end); 695 } 696 assert(chunk->is_valid_sentinel(), "Invalid chunk at address %p.", p); 697 if (chunk->get_chunk_type() != HumongousIndex) { 698 guarantee(is_aligned(p, chunk->word_size()), "Chunk %p not aligned.", p); 699 } 700 chunk_end = p + chunk->word_size(); 701 nth_bit_for_chunk = 0; 702 assert(chunk_end <= to, "Chunk end overlaps test address range."); 703 } else { 704 // No chunk start marked in bitmap. 705 assert(chunk != NULL, "Chunk should start at start of address range."); 706 assert(p < chunk_end, "Did not find expected chunk start at %p.", p); 707 nth_bit_for_chunk ++; 708 } 709 // Check the in-use-info: 710 const bool in_use_bit = get_bit_at_position(pos, layer_in_use_map); 711 if (in_use_bit) { 712 assert(!chunk->is_tagged_free(), "Chunk %p: marked in-use in map but is free (bit %u).", 713 chunk, nth_bit_for_chunk); 714 } else { 715 assert(chunk->is_tagged_free(), "Chunk %p: marked free in map but is in use (bit %u).", 716 chunk, nth_bit_for_chunk); 717 } 718 } 719 } 720 721 // Verify that a given chunk is correctly accounted for in the bitmap. 722 void verify_for_chunk(Metachunk* chunk) { 723 assert(chunk_starts_at_address((MetaWord*) chunk), 724 "No chunk start marked in map for chunk %p.", chunk); 725 // For chunks larger than the minimal chunk size, no other chunk 726 // must start in its area. 727 if (chunk->word_size() > _smallest_chunk_word_size) { 728 assert(!is_any_bit_set_in_region(((MetaWord*) chunk) + _smallest_chunk_word_size, 729 chunk->word_size() - _smallest_chunk_word_size, layer_chunk_start_map), 730 "No chunk must start within another chunk."); 731 } 732 if (!chunk->is_tagged_free()) { 733 assert(is_region_in_use((MetaWord*)chunk, chunk->word_size()), 734 "Chunk %p is in use but marked as free in map (%d %d).", 735 chunk, chunk->get_chunk_type(), chunk->get_origin()); 736 } else { 737 assert(!is_region_in_use((MetaWord*)chunk, chunk->word_size()), 738 "Chunk %p is free but marked as in-use in map (%d %d).", 739 chunk, chunk->get_chunk_type(), chunk->get_origin()); 740 } 741 } 742 743 #endif // ASSERT 744 745 }; 746 747 // A VirtualSpaceList node. 748 class VirtualSpaceNode : public CHeapObj<mtClass> { 749 friend class VirtualSpaceList; 750 751 // Link to next VirtualSpaceNode 752 VirtualSpaceNode* _next; 753 754 // Whether this node is contained in class or metaspace. 755 const bool _is_class; 756 757 // total in the VirtualSpace 758 MemRegion _reserved; 759 ReservedSpace _rs; 760 VirtualSpace _virtual_space; 761 MetaWord* _top; 762 // count of chunks contained in this VirtualSpace 763 uintx _container_count; 764 765 OccupancyMap* _occupancy_map; 766 767 // Convenience functions to access the _virtual_space 768 char* low() const { return virtual_space()->low(); } 769 char* high() const { return virtual_space()->high(); } 770 771 // The first Metachunk will be allocated at the bottom of the 772 // VirtualSpace 773 Metachunk* first_chunk() { return (Metachunk*) bottom(); } 774 775 // Committed but unused space in the virtual space 776 size_t free_words_in_vs() const; 777 778 // True if this node belongs to class metaspace. 779 bool is_class() const { return _is_class; } 780 781 // Helper function for take_from_committed: allocate padding chunks 782 // until top is at the given address. 783 void allocate_padding_chunks_until_top_is_at(MetaWord* target_top); 784 785 public: 786 787 VirtualSpaceNode(bool is_class, size_t byte_size); 788 VirtualSpaceNode(bool is_class, ReservedSpace rs) : 789 _is_class(is_class), _top(NULL), _next(NULL), _rs(rs), _container_count(0), _occupancy_map(NULL) {} 790 ~VirtualSpaceNode(); 791 792 // Convenience functions for logical bottom and end 793 MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); } 794 MetaWord* end() const { return (MetaWord*) _virtual_space.high(); } 795 796 const OccupancyMap* occupancy_map() const { return _occupancy_map; } 797 OccupancyMap* occupancy_map() { return _occupancy_map; } 798 799 bool contains(const void* ptr) { return ptr >= low() && ptr < high(); } 800 801 size_t reserved_words() const { return _virtual_space.reserved_size() / BytesPerWord; } 802 size_t committed_words() const { return _virtual_space.actual_committed_size() / BytesPerWord; } 803 804 bool is_pre_committed() const { return _virtual_space.special(); } 805 806 // address of next available space in _virtual_space; 807 // Accessors 808 VirtualSpaceNode* next() { return _next; } 809 void set_next(VirtualSpaceNode* v) { _next = v; } 810 811 void set_reserved(MemRegion const v) { _reserved = v; } 812 void set_top(MetaWord* v) { _top = v; } 813 814 // Accessors 815 MemRegion* reserved() { return &_reserved; } 816 VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; } 817 818 // Returns true if "word_size" is available in the VirtualSpace 819 bool is_available(size_t word_size) { return word_size <= pointer_delta(end(), _top, sizeof(MetaWord)); } 820 821 MetaWord* top() const { return _top; } 822 void inc_top(size_t word_size) { _top += word_size; } 823 824 uintx container_count() { return _container_count; } 825 void inc_container_count(); 826 void dec_container_count(); 827 #ifdef ASSERT 828 uintx container_count_slow(); 829 void verify_container_count(); 830 #endif 831 832 // used and capacity in this single entry in the list 833 size_t used_words_in_vs() const; 834 size_t capacity_words_in_vs() const; 835 836 bool initialize(); 837 838 // get space from the virtual space 839 Metachunk* take_from_committed(size_t chunk_word_size); 840 841 // Allocate a chunk from the virtual space and return it. 842 Metachunk* get_chunk_vs(size_t chunk_word_size); 843 844 // Expands/shrinks the committed space in a virtual space. Delegates 845 // to Virtualspace 846 bool expand_by(size_t min_words, size_t preferred_words); 847 848 // In preparation for deleting this node, remove all the chunks 849 // in the node from any freelist. 850 void purge(ChunkManager* chunk_manager); 851 852 // If an allocation doesn't fit in the current node a new node is created. 853 // Allocate chunks out of the remaining committed space in this node 854 // to avoid wasting that memory. 855 // This always adds up because all the chunk sizes are multiples of 856 // the smallest chunk size. 857 void retire(ChunkManager* chunk_manager); 858 859 860 void print_on(outputStream* st) const; 861 void print_map(outputStream* st, bool is_class) const; 862 863 // Debug support 864 DEBUG_ONLY(void mangle();) 865 // Verify counters, all chunks in this list node and the occupancy map. 866 DEBUG_ONLY(void verify();) 867 // Verify that all free chunks in this node are ideally merged 868 // (there not should be multiple small chunks where a large chunk could exist.) 869 DEBUG_ONLY(void verify_free_chunks_are_ideally_merged();) 870 871 }; 872 873 #define assert_is_aligned(value, alignment) \ 874 assert(is_aligned((value), (alignment)), \ 875 SIZE_FORMAT_HEX " is not aligned to " \ 876 SIZE_FORMAT, (size_t)(uintptr_t)value, (alignment)) 877 878 // Decide if large pages should be committed when the memory is reserved. 879 static bool should_commit_large_pages_when_reserving(size_t bytes) { 880 if (UseLargePages && UseLargePagesInMetaspace && !os::can_commit_large_page_memory()) { 881 size_t words = bytes / BytesPerWord; 882 bool is_class = false; // We never reserve large pages for the class space. 883 if (MetaspaceGC::can_expand(words, is_class) && 884 MetaspaceGC::allowed_expansion() >= words) { 885 return true; 886 } 887 } 888 889 return false; 890 } 891 892 // byte_size is the size of the associated virtualspace. 893 VirtualSpaceNode::VirtualSpaceNode(bool is_class, size_t bytes) : 894 _is_class(is_class), _top(NULL), _next(NULL), _rs(), _container_count(0), _occupancy_map(NULL) { 895 assert_is_aligned(bytes, Metaspace::reserve_alignment()); 896 bool large_pages = should_commit_large_pages_when_reserving(bytes); 897 _rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages); 898 899 if (_rs.is_reserved()) { 900 assert(_rs.base() != NULL, "Catch if we get a NULL address"); 901 assert(_rs.size() != 0, "Catch if we get a 0 size"); 902 assert_is_aligned(_rs.base(), Metaspace::reserve_alignment()); 903 assert_is_aligned(_rs.size(), Metaspace::reserve_alignment()); 904 905 MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass); 906 } 907 } 908 909 void VirtualSpaceNode::purge(ChunkManager* chunk_manager) { 910 DEBUG_ONLY(this->verify();) 911 Metachunk* chunk = first_chunk(); 912 Metachunk* invalid_chunk = (Metachunk*) top(); 913 while (chunk < invalid_chunk ) { 914 assert(chunk->is_tagged_free(), "Should be tagged free"); 915 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 916 chunk_manager->remove_chunk(chunk); 917 chunk->remove_sentinel(); 918 assert(chunk->next() == NULL && 919 chunk->prev() == NULL, 920 "Was not removed from its list"); 921 chunk = (Metachunk*) next; 922 } 923 } 924 925 void VirtualSpaceNode::print_map(outputStream* st, bool is_class) const { 926 927 if (bottom() == top()) { 928 return; 929 } 930 931 const size_t spec_chunk_size = is_class ? ClassSpecializedChunk : SpecializedChunk; 932 const size_t small_chunk_size = is_class ? ClassSmallChunk : SmallChunk; 933 const size_t med_chunk_size = is_class ? ClassMediumChunk : MediumChunk; 934 935 int line_len = 100; 936 const size_t section_len = align_up(spec_chunk_size * line_len, med_chunk_size); 937 line_len = (int)(section_len / spec_chunk_size); 938 939 static const int NUM_LINES = 4; 940 941 char* lines[NUM_LINES]; 942 for (int i = 0; i < NUM_LINES; i ++) { 943 lines[i] = (char*)os::malloc(line_len, mtInternal); 944 } 945 int pos = 0; 946 const MetaWord* p = bottom(); 947 const Metachunk* chunk = (const Metachunk*)p; 948 const MetaWord* chunk_end = p + chunk->word_size(); 949 while (p < top()) { 950 if (pos == line_len) { 951 pos = 0; 952 for (int i = 0; i < NUM_LINES; i ++) { 953 st->fill_to(22); 954 st->print_raw(lines[i], line_len); 955 st->cr(); 956 } 957 } 958 if (pos == 0) { 959 st->print(PTR_FORMAT ":", p2i(p)); 960 } 961 if (p == chunk_end) { 962 chunk = (Metachunk*)p; 963 chunk_end = p + chunk->word_size(); 964 } 965 // line 1: chunk starting points (a dot if that area is a chunk start). 966 lines[0][pos] = p == (const MetaWord*)chunk ? '.' : ' '; 967 968 // Line 2: chunk type (x=spec, s=small, m=medium, h=humongous), uppercase if 969 // chunk is in use. 970 const bool chunk_is_free = ((Metachunk*)chunk)->is_tagged_free(); 971 if (chunk->word_size() == spec_chunk_size) { 972 lines[1][pos] = chunk_is_free ? 'x' : 'X'; 973 } else if (chunk->word_size() == small_chunk_size) { 974 lines[1][pos] = chunk_is_free ? 's' : 'S'; 975 } else if (chunk->word_size() == med_chunk_size) { 976 lines[1][pos] = chunk_is_free ? 'm' : 'M'; 977 } else if (chunk->word_size() > med_chunk_size) { 978 lines[1][pos] = chunk_is_free ? 'h' : 'H'; 979 } else { 980 ShouldNotReachHere(); 981 } 982 983 // Line 3: chunk origin 984 const ChunkOrigin origin = chunk->get_origin(); 985 lines[2][pos] = origin == origin_normal ? ' ' : '0' + (int) origin; 986 987 // Line 4: Virgin chunk? Virgin chunks are chunks created as a byproduct of padding or splitting, 988 // but were never used. 989 lines[3][pos] = chunk->get_use_count() > 0 ? ' ' : 'v'; 990 991 p += spec_chunk_size; 992 pos ++; 993 } 994 if (pos > 0) { 995 for (int i = 0; i < NUM_LINES; i ++) { 996 st->fill_to(22); 997 st->print_raw(lines[i], line_len); 998 st->cr(); 999 } 1000 } 1001 for (int i = 0; i < NUM_LINES; i ++) { 1002 os::free(lines[i]); 1003 } 1004 } 1005 1006 1007 #ifdef ASSERT 1008 uintx VirtualSpaceNode::container_count_slow() { 1009 uintx count = 0; 1010 Metachunk* chunk = first_chunk(); 1011 Metachunk* invalid_chunk = (Metachunk*) top(); 1012 while (chunk < invalid_chunk ) { 1013 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 1014 do_verify_chunk(chunk); 1015 // Don't count the chunks on the free lists. Those are 1016 // still part of the VirtualSpaceNode but not currently 1017 // counted. 1018 if (!chunk->is_tagged_free()) { 1019 count++; 1020 } 1021 chunk = (Metachunk*) next; 1022 } 1023 return count; 1024 } 1025 #endif 1026 1027 #ifdef ASSERT 1028 // Verify counters, all chunks in this list node and the occupancy map. 1029 void VirtualSpaceNode::verify() { 1030 uintx num_in_use_chunks = 0; 1031 Metachunk* chunk = first_chunk(); 1032 Metachunk* invalid_chunk = (Metachunk*) top(); 1033 1034 // Iterate the chunks in this node and verify each chunk. 1035 while (chunk < invalid_chunk ) { 1036 DEBUG_ONLY(do_verify_chunk(chunk);) 1037 if (!chunk->is_tagged_free()) { 1038 num_in_use_chunks ++; 1039 } 1040 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 1041 chunk = (Metachunk*) next; 1042 } 1043 assert(_container_count == num_in_use_chunks, "Container count mismatch (real: " UINTX_FORMAT 1044 ", counter: " UINTX_FORMAT ".", num_in_use_chunks, _container_count); 1045 // Also verify the occupancy map. 1046 occupancy_map()->verify(this->bottom(), this->top()); 1047 } 1048 #endif // ASSERT 1049 1050 #ifdef ASSERT 1051 // Verify that all free chunks in this node are ideally merged 1052 // (there not should be multiple small chunks where a large chunk could exist.) 1053 void VirtualSpaceNode::verify_free_chunks_are_ideally_merged() { 1054 Metachunk* chunk = first_chunk(); 1055 Metachunk* invalid_chunk = (Metachunk*) top(); 1056 // Shorthands. 1057 const size_t size_med = (is_class() ? ClassMediumChunk : MediumChunk) * BytesPerWord; 1058 const size_t size_small = (is_class() ? ClassSmallChunk : SmallChunk) * BytesPerWord; 1059 int num_free_chunks_since_last_med_boundary = -1; 1060 int num_free_chunks_since_last_small_boundary = -1; 1061 while (chunk < invalid_chunk ) { 1062 // Test for missed chunk merge opportunities: count number of free chunks since last chunk boundary. 1063 // Reset the counter when encountering a non-free chunk. 1064 if (chunk->get_chunk_type() != HumongousIndex) { 1065 if (chunk->is_tagged_free()) { 1066 // Count successive free, non-humongous chunks. 1067 if (is_aligned(chunk, size_small)) { 1068 assert(num_free_chunks_since_last_small_boundary <= 1, 1069 "Missed chunk merge opportunity at " PTR_FORMAT " for chunk size " SIZE_FORMAT_HEX ".", p2i(chunk) - size_small, size_small); 1070 num_free_chunks_since_last_small_boundary = 0; 1071 } else if (num_free_chunks_since_last_small_boundary != -1) { 1072 num_free_chunks_since_last_small_boundary ++; 1073 } 1074 if (is_aligned(chunk, size_med)) { 1075 assert(num_free_chunks_since_last_med_boundary <= 1, 1076 "Missed chunk merge opportunity at " PTR_FORMAT " for chunk size " SIZE_FORMAT_HEX ".", p2i(chunk) - size_med, size_med); 1077 num_free_chunks_since_last_med_boundary = 0; 1078 } else if (num_free_chunks_since_last_med_boundary != -1) { 1079 num_free_chunks_since_last_med_boundary ++; 1080 } 1081 } else { 1082 // Encountering a non-free chunk, reset counters. 1083 num_free_chunks_since_last_med_boundary = -1; 1084 num_free_chunks_since_last_small_boundary = -1; 1085 } 1086 } else { 1087 // One cannot merge areas with a humongous chunk in the middle. Reset counters. 1088 num_free_chunks_since_last_med_boundary = -1; 1089 num_free_chunks_since_last_small_boundary = -1; 1090 } 1091 1092 MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); 1093 chunk = (Metachunk*) next; 1094 } 1095 } 1096 #endif // ASSERT 1097 1098 // List of VirtualSpaces for metadata allocation. 1099 class VirtualSpaceList : public CHeapObj<mtClass> { 1100 friend class VirtualSpaceNode; 1101 1102 enum VirtualSpaceSizes { 1103 VirtualSpaceSize = 256 * K 1104 }; 1105 1106 // Head of the list 1107 VirtualSpaceNode* _virtual_space_list; 1108 // virtual space currently being used for allocations 1109 VirtualSpaceNode* _current_virtual_space; 1110 1111 // Is this VirtualSpaceList used for the compressed class space 1112 bool _is_class; 1113 1114 // Sum of reserved and committed memory in the virtual spaces 1115 size_t _reserved_words; 1116 size_t _committed_words; 1117 1118 // Number of virtual spaces 1119 size_t _virtual_space_count; 1120 1121 ~VirtualSpaceList(); 1122 1123 VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; } 1124 1125 void set_virtual_space_list(VirtualSpaceNode* v) { 1126 _virtual_space_list = v; 1127 } 1128 void set_current_virtual_space(VirtualSpaceNode* v) { 1129 _current_virtual_space = v; 1130 } 1131 1132 void link_vs(VirtualSpaceNode* new_entry); 1133 1134 // Get another virtual space and add it to the list. This 1135 // is typically prompted by a failed attempt to allocate a chunk 1136 // and is typically followed by the allocation of a chunk. 1137 bool create_new_virtual_space(size_t vs_word_size); 1138 1139 // Chunk up the unused committed space in the current 1140 // virtual space and add the chunks to the free list. 1141 void retire_current_virtual_space(); 1142 1143 public: 1144 VirtualSpaceList(size_t word_size); 1145 VirtualSpaceList(ReservedSpace rs); 1146 1147 size_t free_bytes(); 1148 1149 Metachunk* get_new_chunk(size_t chunk_word_size, 1150 size_t suggested_commit_granularity); 1151 1152 bool expand_node_by(VirtualSpaceNode* node, 1153 size_t min_words, 1154 size_t preferred_words); 1155 1156 bool expand_by(size_t min_words, 1157 size_t preferred_words); 1158 1159 VirtualSpaceNode* current_virtual_space() { 1160 return _current_virtual_space; 1161 } 1162 1163 bool is_class() const { return _is_class; } 1164 1165 bool initialization_succeeded() { return _virtual_space_list != NULL; } 1166 1167 size_t reserved_words() { return _reserved_words; } 1168 size_t reserved_bytes() { return reserved_words() * BytesPerWord; } 1169 size_t committed_words() { return _committed_words; } 1170 size_t committed_bytes() { return committed_words() * BytesPerWord; } 1171 1172 void inc_reserved_words(size_t v); 1173 void dec_reserved_words(size_t v); 1174 void inc_committed_words(size_t v); 1175 void dec_committed_words(size_t v); 1176 void inc_virtual_space_count(); 1177 void dec_virtual_space_count(); 1178 1179 bool contains(const void* ptr); 1180 1181 // Unlink empty VirtualSpaceNodes and free it. 1182 void purge(ChunkManager* chunk_manager); 1183 1184 void print_on(outputStream* st) const; 1185 void print_map(outputStream* st) const; 1186 1187 class VirtualSpaceListIterator : public StackObj { 1188 VirtualSpaceNode* _virtual_spaces; 1189 public: 1190 VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) : 1191 _virtual_spaces(virtual_spaces) {} 1192 1193 bool repeat() { 1194 return _virtual_spaces != NULL; 1195 } 1196 1197 VirtualSpaceNode* get_next() { 1198 VirtualSpaceNode* result = _virtual_spaces; 1199 if (_virtual_spaces != NULL) { 1200 _virtual_spaces = _virtual_spaces->next(); 1201 } 1202 return result; 1203 } 1204 }; 1205 }; 1206 1207 class Metadebug : AllStatic { 1208 // Debugging support for Metaspaces 1209 static int _allocation_fail_alot_count; 1210 1211 public: 1212 1213 static void init_allocation_fail_alot_count(); 1214 #ifdef ASSERT 1215 static bool test_metadata_failure(); 1216 #endif 1217 }; 1218 1219 int Metadebug::_allocation_fail_alot_count = 0; 1220 1221 // SpaceManager - used by Metaspace to handle allocations 1222 class SpaceManager : public CHeapObj<mtClass> { 1223 friend class ClassLoaderMetaspace; 1224 friend class Metadebug; 1225 1226 private: 1227 1228 // protects allocations 1229 Mutex* const _lock; 1230 1231 // Type of metadata allocated. 1232 const Metaspace::MetadataType _mdtype; 1233 1234 // Type of metaspace 1235 const Metaspace::MetaspaceType _space_type; 1236 1237 // List of chunks in use by this SpaceManager. Allocations 1238 // are done from the current chunk. The list is used for deallocating 1239 // chunks when the SpaceManager is freed. 1240 Metachunk* _chunks_in_use[NumberOfInUseLists]; 1241 Metachunk* _current_chunk; 1242 1243 // Maximum number of small chunks to allocate to a SpaceManager 1244 static uint const _small_chunk_limit; 1245 1246 // Maximum number of specialize chunks to allocate for anonymous and delegating 1247 // metadata space to a SpaceManager 1248 static uint const _anon_and_delegating_metadata_specialize_chunk_limit; 1249 1250 // Sum of all space in allocated chunks 1251 size_t _allocated_blocks_words; 1252 1253 // Sum of all allocated chunks 1254 size_t _allocated_chunks_words; 1255 size_t _allocated_chunks_count; 1256 1257 // Free lists of blocks are per SpaceManager since they 1258 // are assumed to be in chunks in use by the SpaceManager 1259 // and all chunks in use by a SpaceManager are freed when 1260 // the class loader using the SpaceManager is collected. 1261 BlockFreelist* _block_freelists; 1262 1263 private: 1264 // Accessors 1265 Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; } 1266 void set_chunks_in_use(ChunkIndex index, Metachunk* v) { 1267 _chunks_in_use[index] = v; 1268 } 1269 1270 BlockFreelist* block_freelists() const { return _block_freelists; } 1271 1272 Metaspace::MetadataType mdtype() { return _mdtype; } 1273 1274 VirtualSpaceList* vs_list() const { return Metaspace::get_space_list(_mdtype); } 1275 ChunkManager* chunk_manager() const { return Metaspace::get_chunk_manager(_mdtype); } 1276 1277 Metachunk* current_chunk() const { return _current_chunk; } 1278 void set_current_chunk(Metachunk* v) { 1279 _current_chunk = v; 1280 } 1281 1282 Metachunk* find_current_chunk(size_t word_size); 1283 1284 // Add chunk to the list of chunks in use 1285 void add_chunk(Metachunk* v, bool make_current); 1286 void retire_current_chunk(); 1287 1288 Mutex* lock() const { return _lock; } 1289 1290 protected: 1291 void initialize(); 1292 1293 public: 1294 SpaceManager(Metaspace::MetadataType mdtype, 1295 Metaspace::MetaspaceType space_type, 1296 Mutex* lock); 1297 ~SpaceManager(); 1298 1299 enum ChunkMultiples { 1300 MediumChunkMultiple = 4 1301 }; 1302 1303 static size_t specialized_chunk_size(bool is_class) { return is_class ? ClassSpecializedChunk : SpecializedChunk; } 1304 static size_t small_chunk_size(bool is_class) { return is_class ? ClassSmallChunk : SmallChunk; } 1305 static size_t medium_chunk_size(bool is_class) { return is_class ? ClassMediumChunk : MediumChunk; } 1306 1307 static size_t smallest_chunk_size(bool is_class) { return specialized_chunk_size(is_class); } 1308 1309 // Accessors 1310 bool is_class() const { return _mdtype == Metaspace::ClassType; } 1311 1312 size_t specialized_chunk_size() const { return specialized_chunk_size(is_class()); } 1313 size_t small_chunk_size() const { return small_chunk_size(is_class()); } 1314 size_t medium_chunk_size() const { return medium_chunk_size(is_class()); } 1315 1316 size_t smallest_chunk_size() const { return smallest_chunk_size(is_class()); } 1317 1318 size_t medium_chunk_bunch() const { return medium_chunk_size() * MediumChunkMultiple; } 1319 1320 size_t allocated_blocks_words() const { return _allocated_blocks_words; } 1321 size_t allocated_blocks_bytes() const { return _allocated_blocks_words * BytesPerWord; } 1322 size_t allocated_chunks_words() const { return _allocated_chunks_words; } 1323 size_t allocated_chunks_bytes() const { return _allocated_chunks_words * BytesPerWord; } 1324 size_t allocated_chunks_count() const { return _allocated_chunks_count; } 1325 1326 bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); } 1327 1328 // Increment the per Metaspace and global running sums for Metachunks 1329 // by the given size. This is used when a Metachunk to added to 1330 // the in-use list. 1331 void inc_size_metrics(size_t words); 1332 // Increment the per Metaspace and global running sums Metablocks by the given 1333 // size. This is used when a Metablock is allocated. 1334 void inc_used_metrics(size_t words); 1335 // Delete the portion of the running sums for this SpaceManager. That is, 1336 // the globals running sums for the Metachunks and Metablocks are 1337 // decremented for all the Metachunks in-use by this SpaceManager. 1338 void dec_total_from_size_metrics(); 1339 1340 // Adjust the initial chunk size to match one of the fixed chunk list sizes, 1341 // or return the unadjusted size if the requested size is humongous. 1342 static size_t adjust_initial_chunk_size(size_t requested, bool is_class_space); 1343 size_t adjust_initial_chunk_size(size_t requested) const; 1344 1345 // Get the initial chunks size for this metaspace type. 1346 size_t get_initial_chunk_size(Metaspace::MetaspaceType type) const; 1347 1348 size_t sum_capacity_in_chunks_in_use() const; 1349 size_t sum_used_in_chunks_in_use() const; 1350 size_t sum_free_in_chunks_in_use() const; 1351 size_t sum_waste_in_chunks_in_use() const; 1352 size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const; 1353 1354 size_t sum_count_in_chunks_in_use(); 1355 size_t sum_count_in_chunks_in_use(ChunkIndex i); 1356 1357 Metachunk* get_new_chunk(size_t chunk_word_size); 1358 1359 // Block allocation and deallocation. 1360 // Allocates a block from the current chunk 1361 MetaWord* allocate(size_t word_size); 1362 1363 // Helper for allocations 1364 MetaWord* allocate_work(size_t word_size); 1365 1366 // Returns a block to the per manager freelist 1367 void deallocate(MetaWord* p, size_t word_size); 1368 1369 // Based on the allocation size and a minimum chunk size, 1370 // returned chunk size (for expanding space for chunk allocation). 1371 size_t calc_chunk_size(size_t allocation_word_size); 1372 1373 // Called when an allocation from the current chunk fails. 1374 // Gets a new chunk (may require getting a new virtual space), 1375 // and allocates from that chunk. 1376 MetaWord* grow_and_allocate(size_t word_size); 1377 1378 // Notify memory usage to MemoryService. 1379 void track_metaspace_memory_usage(); 1380 1381 // debugging support. 1382 1383 void dump(outputStream* const out) const; 1384 void print_on(outputStream* st) const; 1385 void locked_print_chunks_in_use_on(outputStream* st) const; 1386 1387 void verify(); 1388 void verify_chunk_size(Metachunk* chunk); 1389 #ifdef ASSERT 1390 void verify_allocated_blocks_words(); 1391 #endif 1392 1393 // This adjusts the size given to be greater than the minimum allocation size in 1394 // words for data in metaspace. Esentially the minimum size is currently 3 words. 1395 size_t get_allocation_word_size(size_t word_size) { 1396 size_t byte_size = word_size * BytesPerWord; 1397 1398 size_t raw_bytes_size = MAX2(byte_size, sizeof(Metablock)); 1399 raw_bytes_size = align_up(raw_bytes_size, Metachunk::object_alignment()); 1400 1401 size_t raw_word_size = raw_bytes_size / BytesPerWord; 1402 assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem"); 1403 1404 return raw_word_size; 1405 } 1406 }; 1407 1408 uint const SpaceManager::_small_chunk_limit = 4; 1409 uint const SpaceManager::_anon_and_delegating_metadata_specialize_chunk_limit = 4; 1410 1411 void VirtualSpaceNode::inc_container_count() { 1412 assert_lock_strong(MetaspaceExpand_lock); 1413 _container_count++; 1414 } 1415 1416 void VirtualSpaceNode::dec_container_count() { 1417 assert_lock_strong(MetaspaceExpand_lock); 1418 _container_count--; 1419 } 1420 1421 #ifdef ASSERT 1422 void VirtualSpaceNode::verify_container_count() { 1423 assert(_container_count == container_count_slow(), 1424 "Inconsistency in container_count _container_count " UINTX_FORMAT 1425 " container_count_slow() " UINTX_FORMAT, _container_count, container_count_slow()); 1426 } 1427 #endif 1428 1429 // BlockFreelist methods 1430 1431 BlockFreelist::BlockFreelist() : _dictionary(new BlockTreeDictionary()), _small_blocks(NULL) {} 1432 1433 BlockFreelist::~BlockFreelist() { 1434 delete _dictionary; 1435 if (_small_blocks != NULL) { 1436 delete _small_blocks; 1437 } 1438 } 1439 1440 void BlockFreelist::return_block(MetaWord* p, size_t word_size) { 1441 assert(word_size >= SmallBlocks::small_block_min_size(), "never return dark matter"); 1442 1443 Metablock* free_chunk = ::new (p) Metablock(word_size); 1444 if (word_size < SmallBlocks::small_block_max_size()) { 1445 small_blocks()->return_block(free_chunk, word_size); 1446 } else { 1447 dictionary()->return_chunk(free_chunk); 1448 } 1449 log_trace(gc, metaspace, freelist, blocks)("returning block at " INTPTR_FORMAT " size = " 1450 SIZE_FORMAT, p2i(free_chunk), word_size); 1451 } 1452 1453 MetaWord* BlockFreelist::get_block(size_t word_size) { 1454 assert(word_size >= SmallBlocks::small_block_min_size(), "never get dark matter"); 1455 1456 // Try small_blocks first. 1457 if (word_size < SmallBlocks::small_block_max_size()) { 1458 // Don't create small_blocks() until needed. small_blocks() allocates the small block list for 1459 // this space manager. 1460 MetaWord* new_block = (MetaWord*) small_blocks()->get_block(word_size); 1461 if (new_block != NULL) { 1462 log_trace(gc, metaspace, freelist, blocks)("getting block at " INTPTR_FORMAT " size = " SIZE_FORMAT, 1463 p2i(new_block), word_size); 1464 return new_block; 1465 } 1466 } 1467 1468 if (word_size < BlockFreelist::min_dictionary_size()) { 1469 // If allocation in small blocks fails, this is Dark Matter. Too small for dictionary. 1470 return NULL; 1471 } 1472 1473 Metablock* free_block = dictionary()->get_chunk(word_size); 1474 if (free_block == NULL) { 1475 return NULL; 1476 } 1477 1478 const size_t block_size = free_block->size(); 1479 if (block_size > WasteMultiplier * word_size) { 1480 return_block((MetaWord*)free_block, block_size); 1481 return NULL; 1482 } 1483 1484 MetaWord* new_block = (MetaWord*)free_block; 1485 assert(block_size >= word_size, "Incorrect size of block from freelist"); 1486 const size_t unused = block_size - word_size; 1487 if (unused >= SmallBlocks::small_block_min_size()) { 1488 return_block(new_block + word_size, unused); 1489 } 1490 1491 log_trace(gc, metaspace, freelist, blocks)("getting block at " INTPTR_FORMAT " size = " SIZE_FORMAT, 1492 p2i(new_block), word_size); 1493 return new_block; 1494 } 1495 1496 void BlockFreelist::print_on(outputStream* st) const { 1497 dictionary()->print_free_lists(st); 1498 if (_small_blocks != NULL) { 1499 _small_blocks->print_on(st); 1500 } 1501 } 1502 1503 // VirtualSpaceNode methods 1504 1505 VirtualSpaceNode::~VirtualSpaceNode() { 1506 _rs.release(); 1507 if (_occupancy_map != NULL) { 1508 delete _occupancy_map; 1509 } 1510 #ifdef ASSERT 1511 size_t word_size = sizeof(*this) / BytesPerWord; 1512 Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1); 1513 #endif 1514 } 1515 1516 size_t VirtualSpaceNode::used_words_in_vs() const { 1517 return pointer_delta(top(), bottom(), sizeof(MetaWord)); 1518 } 1519 1520 // Space committed in the VirtualSpace 1521 size_t VirtualSpaceNode::capacity_words_in_vs() const { 1522 return pointer_delta(end(), bottom(), sizeof(MetaWord)); 1523 } 1524 1525 size_t VirtualSpaceNode::free_words_in_vs() const { 1526 return pointer_delta(end(), top(), sizeof(MetaWord)); 1527 } 1528 1529 // Given an address larger than top(), allocate padding chunks until top is at the given address. 1530 void VirtualSpaceNode::allocate_padding_chunks_until_top_is_at(MetaWord* target_top) { 1531 1532 assert(target_top > top(), "Sanity"); 1533 1534 // Padding chunks are added to the freelist. 1535 ChunkManager* const chunk_manager = Metaspace::get_chunk_manager(this->is_class()); 1536 1537 // shorthands 1538 const size_t spec_word_size = chunk_manager->specialized_chunk_word_size(); 1539 const size_t small_word_size = chunk_manager->small_chunk_word_size(); 1540 const size_t med_word_size = chunk_manager->medium_chunk_word_size(); 1541 1542 while (top() < target_top) { 1543 1544 // We could make this coding more generic, but right now we only deal with two possible chunk sizes 1545 // for padding chunks, so it is not worth it. 1546 size_t padding_chunk_word_size = small_word_size; 1547 if (is_aligned(top(), small_word_size * sizeof(MetaWord)) == false) { 1548 assert_is_aligned(top(), spec_word_size * sizeof(MetaWord)); // Should always hold true. 1549 padding_chunk_word_size = spec_word_size; 1550 } 1551 MetaWord* here = top(); 1552 assert_is_aligned(here, padding_chunk_word_size * sizeof(MetaWord)); 1553 inc_top(padding_chunk_word_size); 1554 1555 // Create new padding chunk. 1556 ChunkIndex padding_chunk_type = get_chunk_type_by_size(padding_chunk_word_size, is_class()); 1557 assert(padding_chunk_type == SpecializedIndex || padding_chunk_type == SmallIndex, "sanity"); 1558 1559 Metachunk* const padding_chunk = 1560 ::new (here) Metachunk(padding_chunk_type, is_class(), padding_chunk_word_size, this); 1561 assert(padding_chunk == (Metachunk*)here, "Sanity"); 1562 DEBUG_ONLY(padding_chunk->set_origin(origin_pad);) 1563 log_trace(gc, metaspace, freelist)("Created padding chunk in %s at " 1564 PTR_FORMAT ", size " SIZE_FORMAT_HEX ".", 1565 (is_class() ? "class space " : "metaspace"), 1566 p2i(padding_chunk), padding_chunk->word_size() * sizeof(MetaWord)); 1567 1568 // Mark chunk start in occupancy map. 1569 occupancy_map()->set_chunk_starts_at_address((MetaWord*)padding_chunk, true); 1570 1571 // Chunks are born as in-use (see MetaChunk ctor). So, before returning 1572 // the padding chunk to its chunk manager, mark it as in use (ChunkManager 1573 // will assert that). 1574 do_update_in_use_info_for_chunk(padding_chunk, true); 1575 1576 // Return Chunk to freelist. 1577 inc_container_count(); 1578 chunk_manager->return_single_chunk(padding_chunk_type, padding_chunk); 1579 // Please note: at this point, ChunkManager::return_single_chunk() 1580 // may already have merged the padding chunk with neighboring chunks, so 1581 // it may have vanished at this point. Do not reference the padding 1582 // chunk beyond this point. 1583 } 1584 1585 assert(top() == target_top, "Sanity"); 1586 1587 } // allocate_padding_chunks_until_top_is_at() 1588 1589 // Allocates the chunk from the virtual space only. 1590 // This interface is also used internally for debugging. Not all 1591 // chunks removed here are necessarily used for allocation. 1592 Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) { 1593 // Non-humongous chunks are to be allocated aligned to their chunk 1594 // size. So, start addresses of medium chunks are aligned to medium 1595 // chunk size, those of small chunks to small chunk size and so 1596 // forth. This facilitates merging of free chunks and reduces 1597 // fragmentation. Chunk sizes are spec < small < medium, with each 1598 // larger chunk size being a multiple of the next smaller chunk 1599 // size. 1600 // Because of this alignment, me may need to create a number of padding 1601 // chunks. These chunks are created and added to the freelist. 1602 1603 // The chunk manager to which we will give our padding chunks. 1604 ChunkManager* const chunk_manager = Metaspace::get_chunk_manager(this->is_class()); 1605 1606 // shorthands 1607 const size_t spec_word_size = chunk_manager->specialized_chunk_word_size(); 1608 const size_t small_word_size = chunk_manager->small_chunk_word_size(); 1609 const size_t med_word_size = chunk_manager->medium_chunk_word_size(); 1610 1611 assert(chunk_word_size == spec_word_size || chunk_word_size == small_word_size || 1612 chunk_word_size >= med_word_size, "Invalid chunk size requested."); 1613 1614 // Chunk alignment (in bytes) == chunk size unless humongous. 1615 // Humongous chunks are aligned to the smallest chunk size (spec). 1616 const size_t required_chunk_alignment = (chunk_word_size > med_word_size ? 1617 spec_word_size : chunk_word_size) * sizeof(MetaWord); 1618 1619 // Do we have enough space to create the requested chunk plus 1620 // any padding chunks needed? 1621 MetaWord* const next_aligned = 1622 static_cast<MetaWord*>(align_up(top(), required_chunk_alignment)); 1623 if (!is_available((next_aligned - top()) + chunk_word_size)) { 1624 return NULL; 1625 } 1626 1627 // Before allocating the requested chunk, allocate padding chunks if necessary. 1628 // We only need to do this for small or medium chunks: specialized chunks are the 1629 // smallest size, hence always aligned. Homungous chunks are allocated unaligned 1630 // (implicitly, also aligned to smallest chunk size). 1631 if ((chunk_word_size == med_word_size || chunk_word_size == small_word_size) && next_aligned > top()) { 1632 log_trace(gc, metaspace, freelist)("Creating padding chunks in %s between %p and %p...", 1633 (is_class() ? "class space " : "metaspace"), 1634 top(), next_aligned); 1635 allocate_padding_chunks_until_top_is_at(next_aligned); 1636 // Now, top should be aligned correctly. 1637 assert_is_aligned(top(), required_chunk_alignment); 1638 } 1639 1640 // Now, top should be aligned correctly. 1641 assert_is_aligned(top(), required_chunk_alignment); 1642 1643 // Bottom of the new chunk 1644 MetaWord* chunk_limit = top(); 1645 assert(chunk_limit != NULL, "Not safe to call this method"); 1646 1647 // The virtual spaces are always expanded by the 1648 // commit granularity to enforce the following condition. 1649 // Without this the is_available check will not work correctly. 1650 assert(_virtual_space.committed_size() == _virtual_space.actual_committed_size(), 1651 "The committed memory doesn't match the expanded memory."); 1652 1653 if (!is_available(chunk_word_size)) { 1654 LogTarget(Debug, gc, metaspace, freelist) lt; 1655 if (lt.is_enabled()) { 1656 LogStream ls(lt); 1657 ls.print("VirtualSpaceNode::take_from_committed() not available " SIZE_FORMAT " words ", chunk_word_size); 1658 // Dump some information about the virtual space that is nearly full 1659 print_on(&ls); 1660 } 1661 return NULL; 1662 } 1663 1664 // Take the space (bump top on the current virtual space). 1665 inc_top(chunk_word_size); 1666 1667 // Initialize the chunk 1668 ChunkIndex chunk_type = get_chunk_type_by_size(chunk_word_size, is_class()); 1669 Metachunk* result = ::new (chunk_limit) Metachunk(chunk_type, is_class(), chunk_word_size, this); 1670 assert(result == (Metachunk*)chunk_limit, "Sanity"); 1671 occupancy_map()->set_chunk_starts_at_address((MetaWord*)result, true); 1672 do_update_in_use_info_for_chunk(result, true); 1673 1674 inc_container_count(); 1675 1676 if (VerifyMetaspace) { 1677 DEBUG_ONLY(chunk_manager->locked_verify()); 1678 DEBUG_ONLY(this->verify()); 1679 } 1680 1681 DEBUG_ONLY(do_verify_chunk(result)); 1682 1683 result->inc_use_count(); 1684 1685 return result; 1686 } 1687 1688 1689 // Expand the virtual space (commit more of the reserved space) 1690 bool VirtualSpaceNode::expand_by(size_t min_words, size_t preferred_words) { 1691 size_t min_bytes = min_words * BytesPerWord; 1692 size_t preferred_bytes = preferred_words * BytesPerWord; 1693 1694 size_t uncommitted = virtual_space()->reserved_size() - virtual_space()->actual_committed_size(); 1695 1696 if (uncommitted < min_bytes) { 1697 return false; 1698 } 1699 1700 size_t commit = MIN2(preferred_bytes, uncommitted); 1701 bool result = virtual_space()->expand_by(commit, false); 1702 1703 if (result) { 1704 log_trace(gc, metaspace, freelist)("Expanded %s virtual space list node by " SIZE_FORMAT " words.", 1705 (is_class() ? "class" : "non-class"), commit); 1706 } else { 1707 log_trace(gc, metaspace, freelist)("Failed to expand %s virtual space list node by " SIZE_FORMAT " words.", 1708 (is_class() ? "class" : "non-class"), commit); 1709 } 1710 1711 assert(result, "Failed to commit memory"); 1712 1713 return result; 1714 } 1715 1716 Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) { 1717 assert_lock_strong(MetaspaceExpand_lock); 1718 Metachunk* result = take_from_committed(chunk_word_size); 1719 return result; 1720 } 1721 1722 bool VirtualSpaceNode::initialize() { 1723 1724 if (!_rs.is_reserved()) { 1725 return false; 1726 } 1727 1728 // These are necessary restriction to make sure that the virtual space always 1729 // grows in steps of Metaspace::commit_alignment(). If both base and size are 1730 // aligned only the middle alignment of the VirtualSpace is used. 1731 assert_is_aligned(_rs.base(), Metaspace::commit_alignment()); 1732 assert_is_aligned(_rs.size(), Metaspace::commit_alignment()); 1733 1734 // ReservedSpaces marked as special will have the entire memory 1735 // pre-committed. Setting a committed size will make sure that 1736 // committed_size and actual_committed_size agrees. 1737 size_t pre_committed_size = _rs.special() ? _rs.size() : 0; 1738 1739 bool result = virtual_space()->initialize_with_granularity(_rs, pre_committed_size, 1740 Metaspace::commit_alignment()); 1741 if (result) { 1742 assert(virtual_space()->committed_size() == virtual_space()->actual_committed_size(), 1743 "Checking that the pre-committed memory was registered by the VirtualSpace"); 1744 1745 set_top((MetaWord*)virtual_space()->low()); 1746 set_reserved(MemRegion((HeapWord*)_rs.base(), 1747 (HeapWord*)(_rs.base() + _rs.size()))); 1748 1749 assert(reserved()->start() == (HeapWord*) _rs.base(), 1750 "Reserved start was not set properly " PTR_FORMAT 1751 " != " PTR_FORMAT, p2i(reserved()->start()), p2i(_rs.base())); 1752 assert(reserved()->word_size() == _rs.size() / BytesPerWord, 1753 "Reserved size was not set properly " SIZE_FORMAT 1754 " != " SIZE_FORMAT, reserved()->word_size(), 1755 _rs.size() / BytesPerWord); 1756 } 1757 1758 // Initialize Occupancy Map. 1759 const size_t smallest_chunk_size = is_class() ? ClassSpecializedChunk : SpecializedChunk; 1760 _occupancy_map = new OccupancyMap(bottom(), reserved_words(), smallest_chunk_size); 1761 1762 return result; 1763 } 1764 1765 void VirtualSpaceNode::print_on(outputStream* st) const { 1766 size_t used = used_words_in_vs(); 1767 size_t capacity = capacity_words_in_vs(); 1768 VirtualSpace* vs = virtual_space(); 1769 st->print_cr(" space @ " PTR_FORMAT " " SIZE_FORMAT "K, " SIZE_FORMAT_W(3) "%% used " 1770 "[" PTR_FORMAT ", " PTR_FORMAT ", " 1771 PTR_FORMAT ", " PTR_FORMAT ")", 1772 p2i(vs), capacity / K, 1773 capacity == 0 ? 0 : used * 100 / capacity, 1774 p2i(bottom()), p2i(top()), p2i(end()), 1775 p2i(vs->high_boundary())); 1776 } 1777 1778 #ifdef ASSERT 1779 void VirtualSpaceNode::mangle() { 1780 size_t word_size = capacity_words_in_vs(); 1781 Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1); 1782 } 1783 #endif // ASSERT 1784 1785 // VirtualSpaceList methods 1786 // Space allocated from the VirtualSpace 1787 1788 VirtualSpaceList::~VirtualSpaceList() { 1789 VirtualSpaceListIterator iter(virtual_space_list()); 1790 while (iter.repeat()) { 1791 VirtualSpaceNode* vsl = iter.get_next(); 1792 delete vsl; 1793 } 1794 } 1795 1796 void VirtualSpaceList::inc_reserved_words(size_t v) { 1797 assert_lock_strong(MetaspaceExpand_lock); 1798 _reserved_words = _reserved_words + v; 1799 } 1800 void VirtualSpaceList::dec_reserved_words(size_t v) { 1801 assert_lock_strong(MetaspaceExpand_lock); 1802 _reserved_words = _reserved_words - v; 1803 } 1804 1805 #define assert_committed_below_limit() \ 1806 assert(MetaspaceUtils::committed_bytes() <= MaxMetaspaceSize, \ 1807 "Too much committed memory. Committed: " SIZE_FORMAT \ 1808 " limit (MaxMetaspaceSize): " SIZE_FORMAT, \ 1809 MetaspaceUtils::committed_bytes(), MaxMetaspaceSize); 1810 1811 void VirtualSpaceList::inc_committed_words(size_t v) { 1812 assert_lock_strong(MetaspaceExpand_lock); 1813 _committed_words = _committed_words + v; 1814 1815 assert_committed_below_limit(); 1816 } 1817 void VirtualSpaceList::dec_committed_words(size_t v) { 1818 assert_lock_strong(MetaspaceExpand_lock); 1819 _committed_words = _committed_words - v; 1820 1821 assert_committed_below_limit(); 1822 } 1823 1824 void VirtualSpaceList::inc_virtual_space_count() { 1825 assert_lock_strong(MetaspaceExpand_lock); 1826 _virtual_space_count++; 1827 } 1828 void VirtualSpaceList::dec_virtual_space_count() { 1829 assert_lock_strong(MetaspaceExpand_lock); 1830 _virtual_space_count--; 1831 } 1832 1833 void ChunkManager::remove_chunk(Metachunk* chunk) { 1834 size_t word_size = chunk->word_size(); 1835 ChunkIndex index = list_index(word_size); 1836 if (index != HumongousIndex) { 1837 free_chunks(index)->remove_chunk(chunk); 1838 } else { 1839 humongous_dictionary()->remove_chunk(chunk); 1840 } 1841 1842 // Chunk has been removed from the chunks free list, update counters. 1843 account_for_removed_chunk(chunk); 1844 } 1845 1846 bool ChunkManager::attempt_to_coalesce_around_chunk(Metachunk* chunk, ChunkIndex target_chunk_type) { 1847 assert_lock_strong(MetaspaceExpand_lock); 1848 assert(chunk != NULL, "invalid chunk pointer"); 1849 // Check for valid merge combinations. 1850 assert((chunk->get_chunk_type() == SpecializedIndex && 1851 (target_chunk_type == SmallIndex || target_chunk_type == MediumIndex)) || 1852 (chunk->get_chunk_type() == SmallIndex && target_chunk_type == MediumIndex), 1853 "Invalid chunk merge combination."); 1854 1855 const size_t target_chunk_word_size = 1856 get_size_for_nonhumongous_chunktype(target_chunk_type, this->is_class()); 1857 1858 // [ prospective merge region ) 1859 MetaWord* const p_merge_region_start = 1860 (MetaWord*) align_down(chunk, target_chunk_word_size * sizeof(MetaWord)); 1861 MetaWord* const p_merge_region_end = 1862 p_merge_region_start + target_chunk_word_size; 1863 1864 // We need the VirtualSpaceNode containing this chunk and its occupancy map. 1865 VirtualSpaceNode* const vsn = chunk->container(); 1866 OccupancyMap* const ocmap = vsn->occupancy_map(); 1867 1868 // The prospective chunk merge range must be completely contained by the 1869 // committed range of the virtual space node. 1870 if (p_merge_region_start < vsn->bottom() || p_merge_region_end > vsn->top()) { 1871 return false; 1872 } 1873 1874 // Only attempt to merge this range if at its start a chunk starts and at its end 1875 // a chunk ends. If a chunk (can only be humongous) straddles either start or end 1876 // of that range, we cannot merge. 1877 if (!ocmap->chunk_starts_at_address(p_merge_region_start)) { 1878 return false; 1879 } 1880 if (p_merge_region_end < vsn->top() && 1881 !ocmap->chunk_starts_at_address(p_merge_region_end)) { 1882 return false; 1883 } 1884 1885 // Now check if the prospective merge area contains live chunks. If it does we cannot merge. 1886 if (ocmap->is_region_in_use(p_merge_region_start, target_chunk_word_size)) { 1887 return false; 1888 } 1889 1890 // Success! Remove all chunks in this region... 1891 log_trace(gc, metaspace, freelist)("%s: coalescing chunks in area [%p-%p)...", 1892 (is_class() ? "class space" : "metaspace"), 1893 p_merge_region_start, p_merge_region_end); 1894 1895 const int num_chunks_removed = 1896 remove_chunks_in_area(p_merge_region_start, target_chunk_word_size); 1897 1898 // ... and create a single new bigger chunk. 1899 Metachunk* const p_new_chunk = 1900 ::new (p_merge_region_start) Metachunk(target_chunk_type, is_class(), target_chunk_word_size, vsn); 1901 assert(p_new_chunk == (Metachunk*)p_merge_region_start, "Sanity"); 1902 p_new_chunk->set_origin(origin_merge); 1903 1904 log_trace(gc, metaspace, freelist)("%s: created coalesced chunk at %p, size " SIZE_FORMAT_HEX ".", 1905 (is_class() ? "class space" : "metaspace"), 1906 p_new_chunk, p_new_chunk->word_size() * sizeof(MetaWord)); 1907 1908 // Fix occupancy map: remove old start bits of the small chunks and set new start bit. 1909 ocmap->wipe_chunk_start_bits_in_region(p_merge_region_start, target_chunk_word_size); 1910 ocmap->set_chunk_starts_at_address(p_merge_region_start, true); 1911 1912 // Mark chunk as free. Note: it is not necessary to update the occupancy 1913 // map in-use map, because the old chunks were also free, so nothing 1914 // should have changed. 1915 p_new_chunk->set_is_tagged_free(true); 1916 1917 // Add new chunk to its freelist. 1918 ChunkList* const list = free_chunks(target_chunk_type); 1919 list->return_chunk_at_head(p_new_chunk); 1920 1921 // And adjust ChunkManager:: _free_chunks_count (_free_chunks_total 1922 // should not have changed, because the size of the space should be the same) 1923 _free_chunks_count -= num_chunks_removed; 1924 _free_chunks_count ++; 1925 1926 // VirtualSpaceNode::container_count does not have to be modified: 1927 // it means "number of active (non-free) chunks", so merging free chunks 1928 // should not affect that count. 1929 1930 // At the end of a chunk merge, run verification tests. 1931 if (VerifyMetaspace) { 1932 DEBUG_ONLY(this->locked_verify()); 1933 DEBUG_ONLY(vsn->verify()); 1934 } 1935 1936 return true; 1937 } 1938 1939 // Remove all chunks in the given area - the chunks are supposed to be free - 1940 // from their corresponding freelists. Mark them as invalid. 1941 // - This does not correct the occupancy map. 1942 // - This does not adjust the counters in ChunkManager. 1943 // - Does not adjust container count counter in containing VirtualSpaceNode 1944 // Returns number of chunks removed. 1945 int ChunkManager::remove_chunks_in_area(MetaWord* p, size_t word_size) { 1946 assert(p != NULL && word_size > 0, "Invalid range."); 1947 const size_t smallest_chunk_size = get_size_for_nonhumongous_chunktype(SpecializedIndex, is_class()); 1948 assert_is_aligned(word_size, smallest_chunk_size); 1949 1950 Metachunk* const start = (Metachunk*) p; 1951 const Metachunk* const end = (Metachunk*)(p + word_size); 1952 Metachunk* cur = start; 1953 int num_removed = 0; 1954 while (cur < end) { 1955 Metachunk* next = (Metachunk*)(((MetaWord*)cur) + cur->word_size()); 1956 DEBUG_ONLY(do_verify_chunk(cur)); 1957 assert(cur->get_chunk_type() != HumongousIndex, "Unexpected humongous chunk found at %p.", cur); 1958 assert(cur->is_tagged_free(), "Chunk expected to be free (%p)", cur); 1959 log_trace(gc, metaspace, freelist)("%s: removing chunk %p, size " SIZE_FORMAT_HEX ".", 1960 (is_class() ? "class space" : "metaspace"), 1961 cur, cur->word_size() * sizeof(MetaWord)); 1962 cur->remove_sentinel(); 1963 // Note: cannot call ChunkManager::remove_chunk, because that 1964 // modifies the counters in ChunkManager, which we do not want. So 1965 // we call remove_chunk on the freelist directly (see also the 1966 // splitting function which does the same). 1967 ChunkList* const list = free_chunks(list_index(cur->word_size())); 1968 list->remove_chunk(cur); 1969 num_removed ++; 1970 cur = next; 1971 } 1972 return num_removed; 1973 } 1974 1975 // Walk the list of VirtualSpaceNodes and delete 1976 // nodes with a 0 container_count. Remove Metachunks in 1977 // the node from their respective freelists. 1978 void VirtualSpaceList::purge(ChunkManager* chunk_manager) { 1979 assert(SafepointSynchronize::is_at_safepoint(), "must be called at safepoint for contains to work"); 1980 assert_lock_strong(MetaspaceExpand_lock); 1981 // Don't use a VirtualSpaceListIterator because this 1982 // list is being changed and a straightforward use of an iterator is not safe. 1983 VirtualSpaceNode* purged_vsl = NULL; 1984 VirtualSpaceNode* prev_vsl = virtual_space_list(); 1985 VirtualSpaceNode* next_vsl = prev_vsl; 1986 while (next_vsl != NULL) { 1987 VirtualSpaceNode* vsl = next_vsl; 1988 DEBUG_ONLY(vsl->verify_container_count();) 1989 next_vsl = vsl->next(); 1990 // Don't free the current virtual space since it will likely 1991 // be needed soon. 1992 if (vsl->container_count() == 0 && vsl != current_virtual_space()) { 1993 log_trace(gc, metaspace, freelist)("Purging VirtualSpaceNode " PTR_FORMAT " (capacity: " SIZE_FORMAT 1994 ", used: " SIZE_FORMAT ").", p2i(vsl), vsl->capacity_words_in_vs(), vsl->used_words_in_vs()); 1995 // Unlink it from the list 1996 if (prev_vsl == vsl) { 1997 // This is the case of the current node being the first node. 1998 assert(vsl == virtual_space_list(), "Expected to be the first node"); 1999 set_virtual_space_list(vsl->next()); 2000 } else { 2001 prev_vsl->set_next(vsl->next()); 2002 } 2003 2004 vsl->purge(chunk_manager); 2005 dec_reserved_words(vsl->reserved_words()); 2006 dec_committed_words(vsl->committed_words()); 2007 dec_virtual_space_count(); 2008 purged_vsl = vsl; 2009 delete vsl; 2010 } else { 2011 prev_vsl = vsl; 2012 } 2013 } 2014 #ifdef ASSERT 2015 if (purged_vsl != NULL) { 2016 // List should be stable enough to use an iterator here. 2017 VirtualSpaceListIterator iter(virtual_space_list()); 2018 while (iter.repeat()) { 2019 VirtualSpaceNode* vsl = iter.get_next(); 2020 assert(vsl != purged_vsl, "Purge of vsl failed"); 2021 } 2022 } 2023 #endif 2024 } 2025 2026 2027 // This function looks at the mmap regions in the metaspace without locking. 2028 // The chunks are added with store ordering and not deleted except for at 2029 // unloading time during a safepoint. 2030 bool VirtualSpaceList::contains(const void* ptr) { 2031 // List should be stable enough to use an iterator here because removing virtual 2032 // space nodes is only allowed at a safepoint. 2033 VirtualSpaceListIterator iter(virtual_space_list()); 2034 while (iter.repeat()) { 2035 VirtualSpaceNode* vsn = iter.get_next(); 2036 if (vsn->contains(ptr)) { 2037 return true; 2038 } 2039 } 2040 return false; 2041 } 2042 2043 void VirtualSpaceList::retire_current_virtual_space() { 2044 assert_lock_strong(MetaspaceExpand_lock); 2045 2046 VirtualSpaceNode* vsn = current_virtual_space(); 2047 2048 ChunkManager* cm = is_class() ? Metaspace::chunk_manager_class() : 2049 Metaspace::chunk_manager_metadata(); 2050 2051 vsn->retire(cm); 2052 } 2053 2054 void VirtualSpaceNode::retire(ChunkManager* chunk_manager) { 2055 DEBUG_ONLY(verify_container_count();) 2056 assert(this->is_class() == chunk_manager->is_class(), "Wrong ChunkManager?"); 2057 for (int i = (int)MediumIndex; i >= (int)ZeroIndex; --i) { 2058 ChunkIndex index = (ChunkIndex)i; 2059 size_t chunk_size = chunk_manager->size_by_index(index); 2060 2061 while (free_words_in_vs() >= chunk_size) { 2062 Metachunk* chunk = get_chunk_vs(chunk_size); 2063 // Chunk will be allocated aligned, so allocation may require 2064 // additional padding chunks. That may cause above allocation to 2065 // fail. Just ignore the failed allocation and continue with the 2066 // next smaller chunk size. As the VirtualSpaceNode comitted 2067 // size should be a multiple of the smallest chunk size, we 2068 // should always be able to fill the VirtualSpace completely. 2069 if (chunk == NULL) { 2070 break; 2071 } 2072 chunk_manager->return_single_chunk(index, chunk); 2073 } 2074 DEBUG_ONLY(verify_container_count();) 2075 } 2076 assert(free_words_in_vs() == 0, "should be empty now"); 2077 } 2078 2079 VirtualSpaceList::VirtualSpaceList(size_t word_size) : 2080 _is_class(false), 2081 _virtual_space_list(NULL), 2082 _current_virtual_space(NULL), 2083 _reserved_words(0), 2084 _committed_words(0), 2085 _virtual_space_count(0) { 2086 MutexLockerEx cl(MetaspaceExpand_lock, 2087 Mutex::_no_safepoint_check_flag); 2088 create_new_virtual_space(word_size); 2089 } 2090 2091 VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) : 2092 _is_class(true), 2093 _virtual_space_list(NULL), 2094 _current_virtual_space(NULL), 2095 _reserved_words(0), 2096 _committed_words(0), 2097 _virtual_space_count(0) { 2098 MutexLockerEx cl(MetaspaceExpand_lock, 2099 Mutex::_no_safepoint_check_flag); 2100 VirtualSpaceNode* class_entry = new VirtualSpaceNode(is_class(), rs); 2101 bool succeeded = class_entry->initialize(); 2102 if (succeeded) { 2103 link_vs(class_entry); 2104 } 2105 } 2106 2107 size_t VirtualSpaceList::free_bytes() { 2108 return current_virtual_space()->free_words_in_vs() * BytesPerWord; 2109 } 2110 2111 // Allocate another meta virtual space and add it to the list. 2112 bool VirtualSpaceList::create_new_virtual_space(size_t vs_word_size) { 2113 assert_lock_strong(MetaspaceExpand_lock); 2114 2115 if (is_class()) { 2116 assert(false, "We currently don't support more than one VirtualSpace for" 2117 " the compressed class space. The initialization of the" 2118 " CCS uses another code path and should not hit this path."); 2119 return false; 2120 } 2121 2122 if (vs_word_size == 0) { 2123 assert(false, "vs_word_size should always be at least _reserve_alignment large."); 2124 return false; 2125 } 2126 2127 // Reserve the space 2128 size_t vs_byte_size = vs_word_size * BytesPerWord; 2129 assert_is_aligned(vs_byte_size, Metaspace::reserve_alignment()); 2130 2131 // Allocate the meta virtual space and initialize it. 2132 VirtualSpaceNode* new_entry = new VirtualSpaceNode(is_class(), vs_byte_size); 2133 if (!new_entry->initialize()) { 2134 delete new_entry; 2135 return false; 2136 } else { 2137 assert(new_entry->reserved_words() == vs_word_size, 2138 "Reserved memory size differs from requested memory size"); 2139 // ensure lock-free iteration sees fully initialized node 2140 OrderAccess::storestore(); 2141 link_vs(new_entry); 2142 return true; 2143 } 2144 } 2145 2146 void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry) { 2147 if (virtual_space_list() == NULL) { 2148 set_virtual_space_list(new_entry); 2149 } else { 2150 current_virtual_space()->set_next(new_entry); 2151 } 2152 set_current_virtual_space(new_entry); 2153 inc_reserved_words(new_entry->reserved_words()); 2154 inc_committed_words(new_entry->committed_words()); 2155 inc_virtual_space_count(); 2156 #ifdef ASSERT 2157 new_entry->mangle(); 2158 #endif 2159 LogTarget(Trace, gc, metaspace) lt; 2160 if (lt.is_enabled()) { 2161 LogStream ls(lt); 2162 VirtualSpaceNode* vsl = current_virtual_space(); 2163 ResourceMark rm; 2164 vsl->print_on(&ls); 2165 } 2166 } 2167 2168 bool VirtualSpaceList::expand_node_by(VirtualSpaceNode* node, 2169 size_t min_words, 2170 size_t preferred_words) { 2171 size_t before = node->committed_words(); 2172 2173 bool result = node->expand_by(min_words, preferred_words); 2174 2175 size_t after = node->committed_words(); 2176 2177 // after and before can be the same if the memory was pre-committed. 2178 assert(after >= before, "Inconsistency"); 2179 inc_committed_words(after - before); 2180 2181 return result; 2182 } 2183 2184 bool VirtualSpaceList::expand_by(size_t min_words, size_t preferred_words) { 2185 assert_is_aligned(min_words, Metaspace::commit_alignment_words()); 2186 assert_is_aligned(preferred_words, Metaspace::commit_alignment_words()); 2187 assert(min_words <= preferred_words, "Invalid arguments"); 2188 2189 const char* const class_or_not = (is_class() ? "class" : "non-class"); 2190 2191 if (!MetaspaceGC::can_expand(min_words, this->is_class())) { 2192 log_trace(gc, metaspace, freelist)("Cannot expand %s virtual space list.", 2193 class_or_not); 2194 return false; 2195 } 2196 2197 size_t allowed_expansion_words = MetaspaceGC::allowed_expansion(); 2198 if (allowed_expansion_words < min_words) { 2199 log_trace(gc, metaspace, freelist)("Cannot expand %s virtual space list (must try gc first).", 2200 class_or_not); 2201 return false; 2202 } 2203 2204 size_t max_expansion_words = MIN2(preferred_words, allowed_expansion_words); 2205 2206 // Commit more memory from the the current virtual space. 2207 bool vs_expanded = expand_node_by(current_virtual_space(), 2208 min_words, 2209 max_expansion_words); 2210 if (vs_expanded) { 2211 log_trace(gc, metaspace, freelist)("Expanded %s virtual space list.", 2212 class_or_not); 2213 return true; 2214 } 2215 log_trace(gc, metaspace, freelist)("%s virtual space list: retire current node.", 2216 class_or_not); 2217 retire_current_virtual_space(); 2218 2219 // Get another virtual space. 2220 size_t grow_vs_words = MAX2((size_t)VirtualSpaceSize, preferred_words); 2221 grow_vs_words = align_up(grow_vs_words, Metaspace::reserve_alignment_words()); 2222 2223 if (create_new_virtual_space(grow_vs_words)) { 2224 if (current_virtual_space()->is_pre_committed()) { 2225 // The memory was pre-committed, so we are done here. 2226 assert(min_words <= current_virtual_space()->committed_words(), 2227 "The new VirtualSpace was pre-committed, so it" 2228 "should be large enough to fit the alloc request."); 2229 return true; 2230 } 2231 2232 return expand_node_by(current_virtual_space(), 2233 min_words, 2234 max_expansion_words); 2235 } 2236 2237 return false; 2238 } 2239 2240 // Given a chunk, calculate the largest possible padding space which 2241 // could be required when allocating it. 2242 static size_t largest_possible_padding_size_for_chunk(size_t chunk_word_size, bool is_class) { 2243 const ChunkIndex chunk_type = get_chunk_type_by_size(chunk_word_size, is_class); 2244 if (chunk_type != HumongousIndex) { 2245 // Normal, non-humongous chunks are allocated at chunk size 2246 // boundaries, so the largest padding space required would be that 2247 // minus the smallest chunk size. 2248 const size_t smallest_chunk_size = is_class ? ClassSpecializedChunk : SpecializedChunk; 2249 return chunk_word_size - smallest_chunk_size; 2250 } else { 2251 // Humongous chunks are allocated at smallest-chunksize 2252 // boundaries, so there is no padding required. 2253 return 0; 2254 } 2255 } 2256 2257 2258 Metachunk* VirtualSpaceList::get_new_chunk(size_t chunk_word_size, size_t suggested_commit_granularity) { 2259 2260 // Allocate a chunk out of the current virtual space. 2261 Metachunk* next = current_virtual_space()->get_chunk_vs(chunk_word_size); 2262 2263 if (next != NULL) { 2264 return next; 2265 } 2266 2267 // The expand amount is currently only determined by the requested sizes 2268 // and not how much committed memory is left in the current virtual space. 2269 2270 // We must have enough space for the requested size and any 2271 // additional reqired padding chunks. 2272 const size_t size_for_padding = largest_possible_padding_size_for_chunk(chunk_word_size, this->is_class()); 2273 2274 size_t min_word_size = align_up(chunk_word_size + size_for_padding, Metaspace::commit_alignment_words()); 2275 size_t preferred_word_size = align_up(suggested_commit_granularity, Metaspace::commit_alignment_words()); 2276 if (min_word_size >= preferred_word_size) { 2277 // Can happen when humongous chunks are allocated. 2278 preferred_word_size = min_word_size; 2279 } 2280 2281 bool expanded = expand_by(min_word_size, preferred_word_size); 2282 if (expanded) { 2283 next = current_virtual_space()->get_chunk_vs(chunk_word_size); 2284 assert(next != NULL, "The allocation was expected to succeed after the expansion"); 2285 } 2286 2287 return next; 2288 } 2289 2290 void VirtualSpaceList::print_on(outputStream* st) const { 2291 VirtualSpaceListIterator iter(virtual_space_list()); 2292 while (iter.repeat()) { 2293 VirtualSpaceNode* node = iter.get_next(); 2294 node->print_on(st); 2295 } 2296 } 2297 2298 void VirtualSpaceList::print_map(outputStream* st) const { 2299 VirtualSpaceNode* list = virtual_space_list(); 2300 VirtualSpaceListIterator iter(list); 2301 unsigned i = 0; 2302 while (iter.repeat()) { 2303 st->print_cr("Node %u:", i); 2304 VirtualSpaceNode* node = iter.get_next(); 2305 node->print_map(st, this->is_class()); 2306 i ++; 2307 } 2308 } 2309 2310 // MetaspaceGC methods 2311 2312 // VM_CollectForMetadataAllocation is the vm operation used to GC. 2313 // Within the VM operation after the GC the attempt to allocate the metadata 2314 // should succeed. If the GC did not free enough space for the metaspace 2315 // allocation, the HWM is increased so that another virtualspace will be 2316 // allocated for the metadata. With perm gen the increase in the perm 2317 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The 2318 // metaspace policy uses those as the small and large steps for the HWM. 2319 // 2320 // After the GC the compute_new_size() for MetaspaceGC is called to 2321 // resize the capacity of the metaspaces. The current implementation 2322 // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used 2323 // to resize the Java heap by some GC's. New flags can be implemented 2324 // if really needed. MinMetaspaceFreeRatio is used to calculate how much 2325 // free space is desirable in the metaspace capacity to decide how much 2326 // to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much 2327 // free space is desirable in the metaspace capacity before decreasing 2328 // the HWM. 2329 2330 // Calculate the amount to increase the high water mark (HWM). 2331 // Increase by a minimum amount (MinMetaspaceExpansion) so that 2332 // another expansion is not requested too soon. If that is not 2333 // enough to satisfy the allocation, increase by MaxMetaspaceExpansion. 2334 // If that is still not enough, expand by the size of the allocation 2335 // plus some. 2336 size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) { 2337 size_t min_delta = MinMetaspaceExpansion; 2338 size_t max_delta = MaxMetaspaceExpansion; 2339 size_t delta = align_up(bytes, Metaspace::commit_alignment()); 2340 2341 if (delta <= min_delta) { 2342 delta = min_delta; 2343 } else if (delta <= max_delta) { 2344 // Don't want to hit the high water mark on the next 2345 // allocation so make the delta greater than just enough 2346 // for this allocation. 2347 delta = max_delta; 2348 } else { 2349 // This allocation is large but the next ones are probably not 2350 // so increase by the minimum. 2351 delta = delta + min_delta; 2352 } 2353 2354 assert_is_aligned(delta, Metaspace::commit_alignment()); 2355 2356 return delta; 2357 } 2358 2359 size_t MetaspaceGC::capacity_until_GC() { 2360 size_t value = OrderAccess::load_acquire(&_capacity_until_GC); 2361 assert(value >= MetaspaceSize, "Not initialized properly?"); 2362 return value; 2363 } 2364 2365 bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC) { 2366 assert_is_aligned(v, Metaspace::commit_alignment()); 2367 2368 intptr_t capacity_until_GC = _capacity_until_GC; 2369 intptr_t new_value = capacity_until_GC + v; 2370 2371 if (new_value < capacity_until_GC) { 2372 // The addition wrapped around, set new_value to aligned max value. 2373 new_value = align_down(max_uintx, Metaspace::commit_alignment()); 2374 } 2375 2376 intptr_t expected = _capacity_until_GC; 2377 intptr_t actual = Atomic::cmpxchg(new_value, &_capacity_until_GC, expected); 2378 2379 if (expected != actual) { 2380 return false; 2381 } 2382 2383 if (new_cap_until_GC != NULL) { 2384 *new_cap_until_GC = new_value; 2385 } 2386 if (old_cap_until_GC != NULL) { 2387 *old_cap_until_GC = capacity_until_GC; 2388 } 2389 return true; 2390 } 2391 2392 size_t MetaspaceGC::dec_capacity_until_GC(size_t v) { 2393 assert_is_aligned(v, Metaspace::commit_alignment()); 2394 2395 return (size_t)Atomic::sub((intptr_t)v, &_capacity_until_GC); 2396 } 2397 2398 void MetaspaceGC::initialize() { 2399 // Set the high-water mark to MaxMetapaceSize during VM initializaton since 2400 // we can't do a GC during initialization. 2401 _capacity_until_GC = MaxMetaspaceSize; 2402 } 2403 2404 void MetaspaceGC::post_initialize() { 2405 // Reset the high-water mark once the VM initialization is done. 2406 _capacity_until_GC = MAX2(MetaspaceUtils::committed_bytes(), MetaspaceSize); 2407 } 2408 2409 bool MetaspaceGC::can_expand(size_t word_size, bool is_class) { 2410 // Check if the compressed class space is full. 2411 if (is_class && Metaspace::using_class_space()) { 2412 size_t class_committed = MetaspaceUtils::committed_bytes(Metaspace::ClassType); 2413 if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) { 2414 log_trace(gc, metaspace, freelist)("Cannot expand %s metaspace by " SIZE_FORMAT " words (CompressedClassSpaceSize = " SIZE_FORMAT " words)", 2415 (is_class ? "class" : "non-class"), word_size, CompressedClassSpaceSize / sizeof(MetaWord)); 2416 return false; 2417 } 2418 } 2419 2420 // Check if the user has imposed a limit on the metaspace memory. 2421 size_t committed_bytes = MetaspaceUtils::committed_bytes(); 2422 if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) { 2423 log_trace(gc, metaspace, freelist)("Cannot expand %s metaspace by " SIZE_FORMAT " words (MaxMetaspaceSize = " SIZE_FORMAT " words)", 2424 (is_class ? "class" : "non-class"), word_size, MaxMetaspaceSize / sizeof(MetaWord)); 2425 return false; 2426 } 2427 2428 return true; 2429 } 2430 2431 size_t MetaspaceGC::allowed_expansion() { 2432 size_t committed_bytes = MetaspaceUtils::committed_bytes(); 2433 size_t capacity_until_gc = capacity_until_GC(); 2434 2435 assert(capacity_until_gc >= committed_bytes, 2436 "capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT, 2437 capacity_until_gc, committed_bytes); 2438 2439 size_t left_until_max = MaxMetaspaceSize - committed_bytes; 2440 size_t left_until_GC = capacity_until_gc - committed_bytes; 2441 size_t left_to_commit = MIN2(left_until_GC, left_until_max); 2442 log_trace(gc, metaspace, freelist)("allowed expansion words: " SIZE_FORMAT 2443 " (left_until_max: " SIZE_FORMAT ", left_until_GC: " SIZE_FORMAT ".", 2444 left_to_commit / BytesPerWord, left_until_max / BytesPerWord, left_until_GC / BytesPerWord); 2445 2446 return left_to_commit / BytesPerWord; 2447 } 2448 2449 void MetaspaceGC::compute_new_size() { 2450 assert(_shrink_factor <= 100, "invalid shrink factor"); 2451 uint current_shrink_factor = _shrink_factor; 2452 _shrink_factor = 0; 2453 2454 // Using committed_bytes() for used_after_gc is an overestimation, since the 2455 // chunk free lists are included in committed_bytes() and the memory in an 2456 // un-fragmented chunk free list is available for future allocations. 2457 // However, if the chunk free lists becomes fragmented, then the memory may 2458 // not be available for future allocations and the memory is therefore "in use". 2459 // Including the chunk free lists in the definition of "in use" is therefore 2460 // necessary. Not including the chunk free lists can cause capacity_until_GC to 2461 // shrink below committed_bytes() and this has caused serious bugs in the past. 2462 const size_t used_after_gc = MetaspaceUtils::committed_bytes(); 2463 const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC(); 2464 2465 const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0; 2466 const double maximum_used_percentage = 1.0 - minimum_free_percentage; 2467 2468 const double min_tmp = used_after_gc / maximum_used_percentage; 2469 size_t minimum_desired_capacity = 2470 (size_t)MIN2(min_tmp, double(max_uintx)); 2471 // Don't shrink less than the initial generation size 2472 minimum_desired_capacity = MAX2(minimum_desired_capacity, 2473 MetaspaceSize); 2474 2475 log_trace(gc, metaspace)("MetaspaceGC::compute_new_size: "); 2476 log_trace(gc, metaspace)(" minimum_free_percentage: %6.2f maximum_used_percentage: %6.2f", 2477 minimum_free_percentage, maximum_used_percentage); 2478 log_trace(gc, metaspace)(" used_after_gc : %6.1fKB", used_after_gc / (double) K); 2479 2480 2481 size_t shrink_bytes = 0; 2482 if (capacity_until_GC < minimum_desired_capacity) { 2483 // If we have less capacity below the metaspace HWM, then 2484 // increment the HWM. 2485 size_t expand_bytes = minimum_desired_capacity - capacity_until_GC; 2486 expand_bytes = align_up(expand_bytes, Metaspace::commit_alignment()); 2487 // Don't expand unless it's significant 2488 if (expand_bytes >= MinMetaspaceExpansion) { 2489 size_t new_capacity_until_GC = 0; 2490 bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC); 2491 assert(succeeded, "Should always succesfully increment HWM when at safepoint"); 2492 2493 Metaspace::tracer()->report_gc_threshold(capacity_until_GC, 2494 new_capacity_until_GC, 2495 MetaspaceGCThresholdUpdater::ComputeNewSize); 2496 log_trace(gc, metaspace)(" expanding: minimum_desired_capacity: %6.1fKB expand_bytes: %6.1fKB MinMetaspaceExpansion: %6.1fKB new metaspace HWM: %6.1fKB", 2497 minimum_desired_capacity / (double) K, 2498 expand_bytes / (double) K, 2499 MinMetaspaceExpansion / (double) K, 2500 new_capacity_until_GC / (double) K); 2501 } 2502 return; 2503 } 2504 2505 // No expansion, now see if we want to shrink 2506 // We would never want to shrink more than this 2507 assert(capacity_until_GC >= minimum_desired_capacity, 2508 SIZE_FORMAT " >= " SIZE_FORMAT, 2509 capacity_until_GC, minimum_desired_capacity); 2510 size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity; 2511 2512 // Should shrinking be considered? 2513 if (MaxMetaspaceFreeRatio < 100) { 2514 const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0; 2515 const double minimum_used_percentage = 1.0 - maximum_free_percentage; 2516 const double max_tmp = used_after_gc / minimum_used_percentage; 2517 size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx)); 2518 maximum_desired_capacity = MAX2(maximum_desired_capacity, 2519 MetaspaceSize); 2520 log_trace(gc, metaspace)(" maximum_free_percentage: %6.2f minimum_used_percentage: %6.2f", 2521 maximum_free_percentage, minimum_used_percentage); 2522 log_trace(gc, metaspace)(" minimum_desired_capacity: %6.1fKB maximum_desired_capacity: %6.1fKB", 2523 minimum_desired_capacity / (double) K, maximum_desired_capacity / (double) K); 2524 2525 assert(minimum_desired_capacity <= maximum_desired_capacity, 2526 "sanity check"); 2527 2528 if (capacity_until_GC > maximum_desired_capacity) { 2529 // Capacity too large, compute shrinking size 2530 shrink_bytes = capacity_until_GC - maximum_desired_capacity; 2531 // We don't want shrink all the way back to initSize if people call 2532 // System.gc(), because some programs do that between "phases" and then 2533 // we'd just have to grow the heap up again for the next phase. So we 2534 // damp the shrinking: 0% on the first call, 10% on the second call, 40% 2535 // on the third call, and 100% by the fourth call. But if we recompute 2536 // size without shrinking, it goes back to 0%. 2537 shrink_bytes = shrink_bytes / 100 * current_shrink_factor; 2538 2539 shrink_bytes = align_down(shrink_bytes, Metaspace::commit_alignment()); 2540 2541 assert(shrink_bytes <= max_shrink_bytes, 2542 "invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT, 2543 shrink_bytes, max_shrink_bytes); 2544 if (current_shrink_factor == 0) { 2545 _shrink_factor = 10; 2546 } else { 2547 _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100); 2548 } 2549 log_trace(gc, metaspace)(" shrinking: initThreshold: %.1fK maximum_desired_capacity: %.1fK", 2550 MetaspaceSize / (double) K, maximum_desired_capacity / (double) K); 2551 log_trace(gc, metaspace)(" shrink_bytes: %.1fK current_shrink_factor: %d new shrink factor: %d MinMetaspaceExpansion: %.1fK", 2552 shrink_bytes / (double) K, current_shrink_factor, _shrink_factor, MinMetaspaceExpansion / (double) K); 2553 } 2554 } 2555 2556 // Don't shrink unless it's significant 2557 if (shrink_bytes >= MinMetaspaceExpansion && 2558 ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) { 2559 size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes); 2560 Metaspace::tracer()->report_gc_threshold(capacity_until_GC, 2561 new_capacity_until_GC, 2562 MetaspaceGCThresholdUpdater::ComputeNewSize); 2563 } 2564 } 2565 2566 // Metadebug methods 2567 2568 void Metadebug::init_allocation_fail_alot_count() { 2569 if (MetadataAllocationFailALot) { 2570 _allocation_fail_alot_count = 2571 1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0)); 2572 } 2573 } 2574 2575 #ifdef ASSERT 2576 bool Metadebug::test_metadata_failure() { 2577 if (MetadataAllocationFailALot && 2578 Threads::is_vm_complete()) { 2579 if (_allocation_fail_alot_count > 0) { 2580 _allocation_fail_alot_count--; 2581 } else { 2582 log_trace(gc, metaspace, freelist)("Metadata allocation failing for MetadataAllocationFailALot"); 2583 init_allocation_fail_alot_count(); 2584 return true; 2585 } 2586 } 2587 return false; 2588 } 2589 #endif 2590 2591 // ChunkManager methods 2592 size_t ChunkManager::free_chunks_total_words() { 2593 return _free_chunks_total; 2594 } 2595 2596 size_t ChunkManager::free_chunks_total_bytes() { 2597 return free_chunks_total_words() * BytesPerWord; 2598 } 2599 2600 // Update internal accounting after a chunk was added 2601 void ChunkManager::account_for_added_chunk(const Metachunk* c) { 2602 assert_lock_strong(MetaspaceExpand_lock); 2603 _free_chunks_count ++; 2604 _free_chunks_total += c->word_size(); 2605 } 2606 2607 // Update internal accounting after a chunk was removed 2608 void ChunkManager::account_for_removed_chunk(const Metachunk* c) { 2609 assert_lock_strong(MetaspaceExpand_lock); 2610 assert(_free_chunks_count >= 1, 2611 "ChunkManager::_free_chunks_count: about to go negative (" SIZE_FORMAT ").", _free_chunks_count); 2612 assert(_free_chunks_total >= c->word_size(), 2613 "ChunkManager::_free_chunks_total: about to go negative" 2614 "(now: " SIZE_FORMAT ", decrement value: " SIZE_FORMAT ").", _free_chunks_total, c->word_size()); 2615 _free_chunks_count --; 2616 _free_chunks_total -= c->word_size(); 2617 } 2618 2619 size_t ChunkManager::free_chunks_count() { 2620 #ifdef ASSERT 2621 if (!UseConcMarkSweepGC && !MetaspaceExpand_lock->is_locked()) { 2622 MutexLockerEx cl(MetaspaceExpand_lock, 2623 Mutex::_no_safepoint_check_flag); 2624 // This lock is only needed in debug because the verification 2625 // of the _free_chunks_totals walks the list of free chunks 2626 slow_locked_verify_free_chunks_count(); 2627 } 2628 #endif 2629 return _free_chunks_count; 2630 } 2631 2632 ChunkIndex ChunkManager::list_index(size_t size) { 2633 return get_chunk_type_by_size(size, is_class()); 2634 } 2635 2636 size_t ChunkManager::size_by_index(ChunkIndex index) const { 2637 index_bounds_check(index); 2638 assert(index != HumongousIndex, "Do not call for humongous chunks."); 2639 return get_size_for_nonhumongous_chunktype(index, is_class()); 2640 } 2641 2642 void ChunkManager::locked_verify_free_chunks_total() { 2643 assert_lock_strong(MetaspaceExpand_lock); 2644 assert(sum_free_chunks() == _free_chunks_total, 2645 "_free_chunks_total " SIZE_FORMAT " is not the" 2646 " same as sum " SIZE_FORMAT, _free_chunks_total, 2647 sum_free_chunks()); 2648 } 2649 2650 void ChunkManager::verify_free_chunks_total() { 2651 MutexLockerEx cl(MetaspaceExpand_lock, 2652 Mutex::_no_safepoint_check_flag); 2653 locked_verify_free_chunks_total(); 2654 } 2655 2656 void ChunkManager::locked_verify_free_chunks_count() { 2657 assert_lock_strong(MetaspaceExpand_lock); 2658 assert(sum_free_chunks_count() == _free_chunks_count, 2659 "_free_chunks_count " SIZE_FORMAT " is not the" 2660 " same as sum " SIZE_FORMAT, _free_chunks_count, 2661 sum_free_chunks_count()); 2662 } 2663 2664 void ChunkManager::verify_free_chunks_count() { 2665 #ifdef ASSERT 2666 MutexLockerEx cl(MetaspaceExpand_lock, 2667 Mutex::_no_safepoint_check_flag); 2668 locked_verify_free_chunks_count(); 2669 #endif 2670 } 2671 2672 void ChunkManager::verify() { 2673 MutexLockerEx cl(MetaspaceExpand_lock, 2674 Mutex::_no_safepoint_check_flag); 2675 locked_verify(); 2676 } 2677 2678 void ChunkManager::locked_verify() { 2679 locked_verify_free_chunks_count(); 2680 locked_verify_free_chunks_total(); 2681 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 2682 ChunkList* list = free_chunks(i); 2683 if (list != NULL) { 2684 Metachunk* chunk = list->head(); 2685 while (chunk) { 2686 DEBUG_ONLY(do_verify_chunk(chunk);) 2687 assert(chunk->is_tagged_free(), "Chunk should be tagged as free."); 2688 chunk = chunk->next(); 2689 } 2690 } 2691 } 2692 } 2693 2694 void ChunkManager::locked_print_free_chunks(outputStream* st) { 2695 assert_lock_strong(MetaspaceExpand_lock); 2696 st->print_cr("Free chunk total " SIZE_FORMAT " count " SIZE_FORMAT, 2697 _free_chunks_total, _free_chunks_count); 2698 } 2699 2700 void ChunkManager::locked_print_sum_free_chunks(outputStream* st) { 2701 assert_lock_strong(MetaspaceExpand_lock); 2702 st->print_cr("Sum free chunk total " SIZE_FORMAT " count " SIZE_FORMAT, 2703 sum_free_chunks(), sum_free_chunks_count()); 2704 } 2705 2706 ChunkList* ChunkManager::free_chunks(ChunkIndex index) { 2707 assert(index == SpecializedIndex || index == SmallIndex || index == MediumIndex, 2708 "Bad index: %d", (int)index); 2709 2710 return &_free_chunks[index]; 2711 } 2712 2713 // These methods that sum the free chunk lists are used in printing 2714 // methods that are used in product builds. 2715 size_t ChunkManager::sum_free_chunks() { 2716 assert_lock_strong(MetaspaceExpand_lock); 2717 size_t result = 0; 2718 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 2719 ChunkList* list = free_chunks(i); 2720 2721 if (list == NULL) { 2722 continue; 2723 } 2724 2725 result = result + list->count() * list->size(); 2726 } 2727 result = result + humongous_dictionary()->total_size(); 2728 return result; 2729 } 2730 2731 size_t ChunkManager::sum_free_chunks_count() { 2732 assert_lock_strong(MetaspaceExpand_lock); 2733 size_t count = 0; 2734 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 2735 ChunkList* list = free_chunks(i); 2736 if (list == NULL) { 2737 continue; 2738 } 2739 count = count + list->count(); 2740 } 2741 count = count + humongous_dictionary()->total_free_blocks(); 2742 return count; 2743 } 2744 2745 ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) { 2746 ChunkIndex index = list_index(word_size); 2747 assert(index < HumongousIndex, "No humongous list"); 2748 return free_chunks(index); 2749 } 2750 2751 // Helper for chunk splitting: given a target chunk size and a larger free chunk, 2752 // split up the larger chunk into n smaller chunks, at least one of which should be 2753 // the target chunk of target chunk size. The smaller chunks, including the target 2754 // chunk, are returned to the freelist. The pointer to the target chunk is returned. 2755 // Note that this chunk is supposed to be removed from the freelist right away. 2756 Metachunk* ChunkManager::split_chunk(size_t target_chunk_word_size, Metachunk* larger_chunk) { 2757 assert(larger_chunk->word_size() > target_chunk_word_size, "Sanity"); 2758 2759 const ChunkIndex larger_chunk_index = larger_chunk->get_chunk_type(); 2760 const ChunkIndex target_chunk_index = get_chunk_type_by_size(target_chunk_word_size, is_class()); 2761 2762 MetaWord* const region_start = (MetaWord*)larger_chunk; 2763 const size_t region_word_len = larger_chunk->word_size(); 2764 MetaWord* const region_end = region_start + region_word_len; 2765 VirtualSpaceNode* const vsn = larger_chunk->container(); 2766 OccupancyMap* const ocmap = vsn->occupancy_map(); 2767 2768 // Any larger non-humongous chunk size is a multiple of any smaller chunk size. 2769 // Since non-humongous chunks are aligned to their chunk size, the larger chunk should start 2770 // at an address suitable to place the smaller target chunk. 2771 assert_is_aligned(region_start, target_chunk_word_size); 2772 2773 // Remove old chunk. 2774 free_chunks(larger_chunk_index)->remove_chunk(larger_chunk); 2775 larger_chunk->remove_sentinel(); 2776 2777 // Prevent access to the old chunk from here on. 2778 larger_chunk = NULL; 2779 // ... and wipe it. 2780 DEBUG_ONLY(memset(region_start, 0xfe, region_word_len * BytesPerWord)); 2781 2782 // In its place create first the target chunk... 2783 MetaWord* p = region_start; 2784 Metachunk* target_chunk = ::new (p) Metachunk(target_chunk_index, is_class(), target_chunk_word_size, vsn); 2785 assert(target_chunk == (Metachunk*)p, "Sanity"); 2786 target_chunk->set_origin(origin_split); 2787 2788 // Note: we do not need to mark its start in the occupancy map 2789 // because it coincides with the old chunk start. 2790 2791 // Mark chunk as free and return to the freelist. 2792 do_update_in_use_info_for_chunk(target_chunk, false); 2793 free_chunks(target_chunk_index)->return_chunk_at_head(target_chunk); 2794 2795 // This chunk should now be valid and can be verified. 2796 DEBUG_ONLY(do_verify_chunk(target_chunk)); 2797 2798 // In the remaining space create the remainder chunks. 2799 p += target_chunk->word_size(); 2800 assert(p < region_end, "Sanity"); 2801 2802 while (p < region_end) { 2803 2804 // Find the largest chunk size which fits the alignment requirements at address p. 2805 ChunkIndex this_chunk_index = prev_chunk_index(larger_chunk_index); 2806 size_t this_chunk_word_size = 0; 2807 for(;;) { 2808 this_chunk_word_size = get_size_for_nonhumongous_chunktype(this_chunk_index, is_class()); 2809 if (is_aligned(p, this_chunk_word_size * BytesPerWord)) { 2810 break; 2811 } else { 2812 this_chunk_index = prev_chunk_index(this_chunk_index); 2813 assert(this_chunk_index >= target_chunk_index, "Sanity"); 2814 } 2815 } 2816 2817 assert(this_chunk_word_size >= target_chunk_word_size, "Sanity"); 2818 assert(is_aligned(p, this_chunk_word_size * BytesPerWord), "Sanity"); 2819 assert(p + this_chunk_word_size <= region_end, "Sanity"); 2820 2821 // Create splitting chunk. 2822 Metachunk* this_chunk = ::new (p) Metachunk(this_chunk_index, is_class(), this_chunk_word_size, vsn); 2823 assert(this_chunk == (Metachunk*)p, "Sanity"); 2824 this_chunk->set_origin(origin_split); 2825 ocmap->set_chunk_starts_at_address(p, true); 2826 do_update_in_use_info_for_chunk(this_chunk, false); 2827 2828 // This chunk should be valid and can be verified. 2829 DEBUG_ONLY(do_verify_chunk(this_chunk)); 2830 2831 // Return this chunk to freelist and correct counter. 2832 free_chunks(this_chunk_index)->return_chunk_at_head(this_chunk); 2833 _free_chunks_count ++; 2834 2835 log_trace(gc, metaspace, freelist)("Created chunk at " PTR_FORMAT ", word size " 2836 SIZE_FORMAT_HEX " (%s), in split region [" PTR_FORMAT "..." PTR_FORMAT ").", 2837 p2i(this_chunk), this_chunk->word_size(), chunk_size_name(this_chunk_index), 2838 p2i(region_start), p2i(region_end)); 2839 2840 p += this_chunk_word_size; 2841 2842 } 2843 2844 return target_chunk; 2845 } 2846 2847 Metachunk* ChunkManager::free_chunks_get(size_t word_size) { 2848 assert_lock_strong(MetaspaceExpand_lock); 2849 2850 slow_locked_verify(); 2851 2852 Metachunk* chunk = NULL; 2853 bool we_did_split_a_chunk = false; 2854 2855 if (list_index(word_size) != HumongousIndex) { 2856 2857 ChunkList* free_list = find_free_chunks_list(word_size); 2858 assert(free_list != NULL, "Sanity check"); 2859 2860 chunk = free_list->head(); 2861 2862 if (chunk == NULL) { 2863 // Split large chunks into smaller chunks if there are no smaller chunks, just large chunks. 2864 // This is the counterpart of the coalescing-upon-chunk-return. 2865 2866 ChunkIndex target_chunk_index = get_chunk_type_by_size(word_size, is_class()); 2867 2868 // Is there a larger chunk we could split? 2869 Metachunk* larger_chunk = NULL; 2870 ChunkIndex larger_chunk_index = next_chunk_index(target_chunk_index); 2871 while (larger_chunk == NULL && larger_chunk_index < NumberOfFreeLists) { 2872 larger_chunk = free_chunks(larger_chunk_index)->head(); 2873 if (larger_chunk == NULL) { 2874 larger_chunk_index = next_chunk_index(larger_chunk_index); 2875 } 2876 } 2877 2878 if (larger_chunk != NULL) { 2879 assert(larger_chunk->word_size() > word_size, "Sanity"); 2880 assert(larger_chunk->get_chunk_type() == larger_chunk_index, "Sanity"); 2881 2882 // We found a larger chunk. Lets split it up: 2883 // - remove old chunk 2884 // - in its place, create new smaller chunks, with at least one chunk 2885 // being of target size, the others sized as large as possible. This 2886 // is to make sure the resulting chunks are "as coalesced as possible" 2887 // (similar to VirtualSpaceNode::retire()). 2888 // Note: during this operation both ChunkManager and VirtualSpaceNode 2889 // are temporarily invalid, so be careful with asserts. 2890 2891 log_trace(gc, metaspace, freelist)("%s: splitting chunk " PTR_FORMAT 2892 ", word size " SIZE_FORMAT_HEX " (%s), to get a chunk of word size " SIZE_FORMAT_HEX " (%s)...", 2893 (is_class() ? "class space" : "metaspace"), p2i(larger_chunk), larger_chunk->word_size(), 2894 chunk_size_name(larger_chunk_index), word_size, chunk_size_name(target_chunk_index)); 2895 2896 chunk = split_chunk(word_size, larger_chunk); 2897 2898 // This should have worked. 2899 assert(chunk != NULL, "Sanity"); 2900 assert(chunk->word_size() == word_size, "Sanity"); 2901 assert(chunk->is_tagged_free(), "Sanity"); 2902 2903 we_did_split_a_chunk = true; 2904 2905 } 2906 } 2907 2908 if (chunk == NULL) { 2909 return NULL; 2910 } 2911 2912 // Remove the chunk as the head of the list. 2913 free_list->remove_chunk(chunk); 2914 2915 log_trace(gc, metaspace, freelist)("ChunkManager::free_chunks_get: free_list: " PTR_FORMAT " chunks left: " SSIZE_FORMAT ".", 2916 p2i(free_list), free_list->count()); 2917 2918 } else { 2919 chunk = humongous_dictionary()->get_chunk(word_size); 2920 2921 if (chunk == NULL) { 2922 return NULL; 2923 } 2924 2925 log_debug(gc, metaspace, alloc)("Free list allocate humongous chunk size " SIZE_FORMAT " for requested size " SIZE_FORMAT " waste " SIZE_FORMAT, 2926 chunk->word_size(), word_size, chunk->word_size() - word_size); 2927 } 2928 2929 // Chunk has been removed from the chunk manager; update counters. 2930 account_for_removed_chunk(chunk); 2931 do_update_in_use_info_for_chunk(chunk, true); 2932 chunk->container()->inc_container_count(); 2933 chunk->inc_use_count(); 2934 2935 // Remove it from the links to this freelist 2936 chunk->set_next(NULL); 2937 chunk->set_prev(NULL); 2938 2939 // Run some verifications (some more if we did a chunk split) 2940 #ifdef ASSERT 2941 if (VerifyMetaspace) { 2942 locked_verify(); 2943 VirtualSpaceNode* const vsn = chunk->container(); 2944 vsn->verify(); 2945 if (we_did_split_a_chunk) { 2946 vsn->verify_free_chunks_are_ideally_merged(); 2947 } 2948 } 2949 #endif 2950 2951 return chunk; 2952 } 2953 2954 Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) { 2955 assert_lock_strong(MetaspaceExpand_lock); 2956 slow_locked_verify(); 2957 2958 // Take from the beginning of the list 2959 Metachunk* chunk = free_chunks_get(word_size); 2960 if (chunk == NULL) { 2961 return NULL; 2962 } 2963 2964 assert((word_size <= chunk->word_size()) || 2965 (list_index(chunk->word_size()) == HumongousIndex), 2966 "Non-humongous variable sized chunk"); 2967 LogTarget(Debug, gc, metaspace, freelist) lt; 2968 if (lt.is_enabled()) { 2969 size_t list_count; 2970 if (list_index(word_size) < HumongousIndex) { 2971 ChunkList* list = find_free_chunks_list(word_size); 2972 list_count = list->count(); 2973 } else { 2974 list_count = humongous_dictionary()->total_count(); 2975 } 2976 LogStream ls(lt); 2977 ls.print("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk " PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ", 2978 p2i(this), p2i(chunk), chunk->word_size(), list_count); 2979 ResourceMark rm; 2980 locked_print_free_chunks(&ls); 2981 } 2982 2983 return chunk; 2984 } 2985 2986 void ChunkManager::return_single_chunk(ChunkIndex index, Metachunk* chunk) { 2987 assert_lock_strong(MetaspaceExpand_lock); 2988 DEBUG_ONLY(do_verify_chunk(chunk);) 2989 assert(chunk->get_chunk_type() == index, "Chunk does not match expected index."); 2990 assert(chunk != NULL, "Expected chunk."); 2991 assert(chunk->container() != NULL, "Container should have been set."); 2992 assert(chunk->is_tagged_free() == false, "Chunk should be in use."); 2993 index_bounds_check(index); 2994 2995 // Note: mangle *before* returning the chunk to the freelist or dictionary. It does not 2996 // matter for the freelist (non-humongous chunks), but the humongous chunk dictionary 2997 // keeps tree node pointers in the chunk payload area which mangle will overwrite. 2998 DEBUG_ONLY(chunk->mangle(badMetaWordVal);) 2999 3000 if (index != HumongousIndex) { 3001 // Return non-humongous chunk to freelist. 3002 ChunkList* list = free_chunks(index); 3003 assert(list->size() == chunk->word_size(), "Wrong chunk type."); 3004 list->return_chunk_at_head(chunk); 3005 log_trace(gc, metaspace, freelist)("returned one %s chunk at " PTR_FORMAT " to freelist.", 3006 chunk_size_name(index), p2i(chunk)); 3007 } else { 3008 // Return humongous chunk to dictionary. 3009 assert(chunk->word_size() > free_chunks(MediumIndex)->size(), "Wrong chunk type."); 3010 assert(chunk->word_size() % free_chunks(SpecializedIndex)->size() == 0, 3011 "Humongous chunk has wrong alignment."); 3012 _humongous_dictionary.return_chunk(chunk); 3013 log_trace(gc, metaspace, freelist)("returned one %s chunk at " PTR_FORMAT " (word size " SIZE_FORMAT ") to freelist.", 3014 chunk_size_name(index), p2i(chunk), chunk->word_size()); 3015 } 3016 chunk->container()->dec_container_count(); 3017 do_update_in_use_info_for_chunk(chunk, false); 3018 3019 // Chunk has been added; update counters. 3020 account_for_added_chunk(chunk); 3021 3022 // Attempt coalesce returned chunks with its neighboring chunks: 3023 // if this chunk is small or special, attempt to coalesce to a medium chunk. 3024 if (index == SmallIndex || index == SpecializedIndex) { 3025 if (!attempt_to_coalesce_around_chunk(chunk, MediumIndex)) { 3026 // This did not work. But if this chunk is special, we still may form a small chunk? 3027 if (index == SpecializedIndex) { 3028 if (!attempt_to_coalesce_around_chunk(chunk, SmallIndex)) { 3029 // give up. 3030 } 3031 } 3032 } 3033 } 3034 3035 } 3036 3037 void ChunkManager::return_chunk_list(ChunkIndex index, Metachunk* chunks) { 3038 index_bounds_check(index); 3039 if (chunks == NULL) { 3040 return; 3041 } 3042 LogTarget(Trace, gc, metaspace, freelist) log; 3043 if (log.is_enabled()) { // tracing 3044 log.print("returning list of %s chunks...", chunk_size_name(index)); 3045 } 3046 unsigned num_chunks_returned = 0; 3047 size_t size_chunks_returned = 0; 3048 Metachunk* cur = chunks; 3049 while (cur != NULL) { 3050 // Capture the next link before it is changed 3051 // by the call to return_chunk_at_head(); 3052 Metachunk* next = cur->next(); 3053 if (log.is_enabled()) { // tracing 3054 num_chunks_returned ++; 3055 size_chunks_returned += cur->word_size(); 3056 } 3057 return_single_chunk(index, cur); 3058 cur = next; 3059 } 3060 if (log.is_enabled()) { // tracing 3061 log.print("returned %u %s chunks to freelist, total word size " SIZE_FORMAT ".", 3062 num_chunks_returned, chunk_size_name(index), size_chunks_returned); 3063 if (index != HumongousIndex) { 3064 log.print("updated freelist count: " SIZE_FORMAT ".", free_chunks(index)->size()); 3065 } else { 3066 log.print("updated dictionary count " SIZE_FORMAT ".", _humongous_dictionary.total_count()); 3067 } 3068 } 3069 } 3070 3071 void ChunkManager::print_on(outputStream* out) const { 3072 _humongous_dictionary.report_statistics(out); 3073 } 3074 3075 void ChunkManager::locked_get_statistics(ChunkManagerStatistics* stat) const { 3076 assert_lock_strong(MetaspaceExpand_lock); 3077 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 3078 stat->num_by_type[i] = num_free_chunks(i); 3079 stat->single_size_by_type[i] = size_by_index(i); 3080 stat->total_size_by_type[i] = size_free_chunks_in_bytes(i); 3081 } 3082 stat->num_humongous_chunks = num_free_chunks(HumongousIndex); 3083 stat->total_size_humongous_chunks = size_free_chunks_in_bytes(HumongousIndex); 3084 } 3085 3086 void ChunkManager::get_statistics(ChunkManagerStatistics* stat) const { 3087 MutexLockerEx cl(MetaspaceExpand_lock, 3088 Mutex::_no_safepoint_check_flag); 3089 locked_get_statistics(stat); 3090 } 3091 3092 void ChunkManager::print_statistics(const ChunkManagerStatistics* stat, outputStream* out, size_t scale) { 3093 size_t total = 0; 3094 assert(scale == 1 || scale == K || scale == M || scale == G, "Invalid scale"); 3095 3096 const char* unit = scale_unit(scale); 3097 for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { 3098 out->print(" " SIZE_FORMAT " %s (" SIZE_FORMAT " bytes) chunks, total ", 3099 stat->num_by_type[i], chunk_size_name(i), 3100 stat->single_size_by_type[i]); 3101 if (scale == 1) { 3102 out->print_cr(SIZE_FORMAT " bytes", stat->total_size_by_type[i]); 3103 } else { 3104 out->print_cr("%.2f%s", (float)stat->total_size_by_type[i] / scale, unit); 3105 } 3106 3107 total += stat->total_size_by_type[i]; 3108 } 3109 3110 3111 total += stat->total_size_humongous_chunks; 3112 3113 if (scale == 1) { 3114 out->print_cr(" " SIZE_FORMAT " humongous chunks, total " SIZE_FORMAT " bytes", 3115 stat->num_humongous_chunks, stat->total_size_humongous_chunks); 3116 3117 out->print_cr(" total size: " SIZE_FORMAT " bytes.", total); 3118 } else { 3119 out->print_cr(" " SIZE_FORMAT " humongous chunks, total %.2f%s", 3120 stat->num_humongous_chunks, 3121 (float)stat->total_size_humongous_chunks / scale, unit); 3122 3123 out->print_cr(" total size: %.2f%s.", (float)total / scale, unit); 3124 } 3125 3126 } 3127 3128 void ChunkManager::print_all_chunkmanagers(outputStream* out, size_t scale) { 3129 assert(scale == 1 || scale == K || scale == M || scale == G, "Invalid scale"); 3130 3131 // Note: keep lock protection only to retrieving statistics; keep printing 3132 // out of lock protection 3133 ChunkManagerStatistics stat; 3134 out->print_cr("Chunkmanager (non-class):"); 3135 const ChunkManager* const non_class_cm = Metaspace::chunk_manager_metadata(); 3136 if (non_class_cm != NULL) { 3137 non_class_cm->get_statistics(&stat); 3138 ChunkManager::print_statistics(&stat, out, scale); 3139 } else { 3140 out->print_cr("unavailable."); 3141 } 3142 out->print_cr("Chunkmanager (class):"); 3143 const ChunkManager* const class_cm = Metaspace::chunk_manager_class(); 3144 if (class_cm != NULL) { 3145 class_cm->get_statistics(&stat); 3146 ChunkManager::print_statistics(&stat, out, scale); 3147 } else { 3148 out->print_cr("unavailable."); 3149 } 3150 } 3151 3152 // SpaceManager methods 3153 3154 size_t SpaceManager::adjust_initial_chunk_size(size_t requested, bool is_class_space) { 3155 size_t chunk_sizes[] = { 3156 specialized_chunk_size(is_class_space), 3157 small_chunk_size(is_class_space), 3158 medium_chunk_size(is_class_space) 3159 }; 3160 3161 // Adjust up to one of the fixed chunk sizes ... 3162 for (size_t i = 0; i < ARRAY_SIZE(chunk_sizes); i++) { 3163 if (requested <= chunk_sizes[i]) { 3164 return chunk_sizes[i]; 3165 } 3166 } 3167 3168 // ... or return the size as a humongous chunk. 3169 return requested; 3170 } 3171 3172 size_t SpaceManager::adjust_initial_chunk_size(size_t requested) const { 3173 return adjust_initial_chunk_size(requested, is_class()); 3174 } 3175 3176 size_t SpaceManager::get_initial_chunk_size(Metaspace::MetaspaceType type) const { 3177 size_t requested; 3178 3179 if (is_class()) { 3180 switch (type) { 3181 case Metaspace::BootMetaspaceType: requested = Metaspace::first_class_chunk_word_size(); break; 3182 case Metaspace::AnonymousMetaspaceType: requested = ClassSpecializedChunk; break; 3183 case Metaspace::ReflectionMetaspaceType: requested = ClassSpecializedChunk; break; 3184 default: requested = ClassSmallChunk; break; 3185 } 3186 } else { 3187 switch (type) { 3188 case Metaspace::BootMetaspaceType: requested = Metaspace::first_chunk_word_size(); break; 3189 case Metaspace::AnonymousMetaspaceType: requested = SpecializedChunk; break; 3190 case Metaspace::ReflectionMetaspaceType: requested = SpecializedChunk; break; 3191 default: requested = SmallChunk; break; 3192 } 3193 } 3194 3195 // Adjust to one of the fixed chunk sizes (unless humongous) 3196 const size_t adjusted = adjust_initial_chunk_size(requested); 3197 3198 assert(adjusted != 0, "Incorrect initial chunk size. Requested: " 3199 SIZE_FORMAT " adjusted: " SIZE_FORMAT, requested, adjusted); 3200 3201 return adjusted; 3202 } 3203 3204 size_t SpaceManager::sum_free_in_chunks_in_use() const { 3205 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 3206 size_t free = 0; 3207 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 3208 Metachunk* chunk = chunks_in_use(i); 3209 while (chunk != NULL) { 3210 free += chunk->free_word_size(); 3211 chunk = chunk->next(); 3212 } 3213 } 3214 return free; 3215 } 3216 3217 size_t SpaceManager::sum_waste_in_chunks_in_use() const { 3218 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 3219 size_t result = 0; 3220 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 3221 result += sum_waste_in_chunks_in_use(i); 3222 } 3223 3224 return result; 3225 } 3226 3227 size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const { 3228 size_t result = 0; 3229 Metachunk* chunk = chunks_in_use(index); 3230 // Count the free space in all the chunk but not the 3231 // current chunk from which allocations are still being done. 3232 while (chunk != NULL) { 3233 if (chunk != current_chunk()) { 3234 result += chunk->free_word_size(); 3235 } 3236 chunk = chunk->next(); 3237 } 3238 return result; 3239 } 3240 3241 size_t SpaceManager::sum_capacity_in_chunks_in_use() const { 3242 // For CMS use "allocated_chunks_words()" which does not need the 3243 // Metaspace lock. For the other collectors sum over the 3244 // lists. Use both methods as a check that "allocated_chunks_words()" 3245 // is correct. That is, sum_capacity_in_chunks() is too expensive 3246 // to use in the product and allocated_chunks_words() should be used 3247 // but allow for checking that allocated_chunks_words() returns the same 3248 // value as sum_capacity_in_chunks_in_use() which is the definitive 3249 // answer. 3250 if (UseConcMarkSweepGC) { 3251 return allocated_chunks_words(); 3252 } else { 3253 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 3254 size_t sum = 0; 3255 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 3256 Metachunk* chunk = chunks_in_use(i); 3257 while (chunk != NULL) { 3258 sum += chunk->word_size(); 3259 chunk = chunk->next(); 3260 } 3261 } 3262 return sum; 3263 } 3264 } 3265 3266 size_t SpaceManager::sum_count_in_chunks_in_use() { 3267 size_t count = 0; 3268 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 3269 count = count + sum_count_in_chunks_in_use(i); 3270 } 3271 3272 return count; 3273 } 3274 3275 size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) { 3276 size_t count = 0; 3277 Metachunk* chunk = chunks_in_use(i); 3278 while (chunk != NULL) { 3279 count++; 3280 chunk = chunk->next(); 3281 } 3282 return count; 3283 } 3284 3285 3286 size_t SpaceManager::sum_used_in_chunks_in_use() const { 3287 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 3288 size_t used = 0; 3289 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 3290 Metachunk* chunk = chunks_in_use(i); 3291 while (chunk != NULL) { 3292 used += chunk->used_word_size(); 3293 chunk = chunk->next(); 3294 } 3295 } 3296 return used; 3297 } 3298 3299 void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const { 3300 3301 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 3302 Metachunk* chunk = chunks_in_use(i); 3303 st->print("SpaceManager: %s " PTR_FORMAT, 3304 chunk_size_name(i), p2i(chunk)); 3305 if (chunk != NULL) { 3306 st->print_cr(" free " SIZE_FORMAT, 3307 chunk->free_word_size()); 3308 } else { 3309 st->cr(); 3310 } 3311 } 3312 3313 chunk_manager()->locked_print_free_chunks(st); 3314 chunk_manager()->locked_print_sum_free_chunks(st); 3315 } 3316 3317 size_t SpaceManager::calc_chunk_size(size_t word_size) { 3318 3319 // Decide between a small chunk and a medium chunk. Up to 3320 // _small_chunk_limit small chunks can be allocated. 3321 // After that a medium chunk is preferred. 3322 size_t chunk_word_size; 3323 3324 // Special case for anonymous metadata space. 3325 // Anonymous metadata space is usually small, with majority within 1K - 2K range and 3326 // rarely about 4K (64-bits JVM). 3327 // Instead of jumping to SmallChunk after initial chunk exhausted, keeping allocation 3328 // from SpecializeChunk up to _anon_or_delegating_metadata_specialize_chunk_limit (4) 3329 // reduces space waste from 60+% to around 30%. 3330 if ((_space_type == Metaspace::AnonymousMetaspaceType || _space_type == Metaspace::ReflectionMetaspaceType) && 3331 _mdtype == Metaspace::NonClassType && 3332 sum_count_in_chunks_in_use(SpecializedIndex) < _anon_and_delegating_metadata_specialize_chunk_limit && 3333 word_size + Metachunk::overhead() <= SpecializedChunk) { 3334 return SpecializedChunk; 3335 } 3336 3337 if (chunks_in_use(MediumIndex) == NULL && 3338 sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit) { 3339 chunk_word_size = (size_t) small_chunk_size(); 3340 if (word_size + Metachunk::overhead() > small_chunk_size()) { 3341 chunk_word_size = medium_chunk_size(); 3342 } 3343 } else { 3344 chunk_word_size = medium_chunk_size(); 3345 } 3346 3347 // Might still need a humongous chunk. Enforce 3348 // humongous allocations sizes to be aligned up to 3349 // the smallest chunk size. 3350 size_t if_humongous_sized_chunk = 3351 align_up(word_size + Metachunk::overhead(), 3352 smallest_chunk_size()); 3353 chunk_word_size = 3354 MAX2((size_t) chunk_word_size, if_humongous_sized_chunk); 3355 3356 assert(!SpaceManager::is_humongous(word_size) || 3357 chunk_word_size == if_humongous_sized_chunk, 3358 "Size calculation is wrong, word_size " SIZE_FORMAT 3359 " chunk_word_size " SIZE_FORMAT, 3360 word_size, chunk_word_size); 3361 Log(gc, metaspace, alloc) log; 3362 if (log.is_debug() && SpaceManager::is_humongous(word_size)) { 3363 log.debug("Metadata humongous allocation:"); 3364 log.debug(" word_size " PTR_FORMAT, word_size); 3365 log.debug(" chunk_word_size " PTR_FORMAT, chunk_word_size); 3366 log.debug(" chunk overhead " PTR_FORMAT, Metachunk::overhead()); 3367 } 3368 return chunk_word_size; 3369 } 3370 3371 void SpaceManager::track_metaspace_memory_usage() { 3372 if (is_init_completed()) { 3373 if (is_class()) { 3374 MemoryService::track_compressed_class_memory_usage(); 3375 } 3376 MemoryService::track_metaspace_memory_usage(); 3377 } 3378 } 3379 3380 MetaWord* SpaceManager::grow_and_allocate(size_t word_size) { 3381 assert_lock_strong(_lock); 3382 assert(vs_list()->current_virtual_space() != NULL, 3383 "Should have been set"); 3384 assert(current_chunk() == NULL || 3385 current_chunk()->allocate(word_size) == NULL, 3386 "Don't need to expand"); 3387 MutexLockerEx cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag); 3388 3389 if (log_is_enabled(Trace, gc, metaspace, freelist)) { 3390 size_t words_left = 0; 3391 size_t words_used = 0; 3392 if (current_chunk() != NULL) { 3393 words_left = current_chunk()->free_word_size(); 3394 words_used = current_chunk()->used_word_size(); 3395 } 3396 log_trace(gc, metaspace, freelist)("SpaceManager::grow_and_allocate for " SIZE_FORMAT " words " SIZE_FORMAT " words used " SIZE_FORMAT " words left", 3397 word_size, words_used, words_left); 3398 } 3399 3400 // Get another chunk 3401 size_t chunk_word_size = calc_chunk_size(word_size); 3402 Metachunk* next = get_new_chunk(chunk_word_size); 3403 3404 MetaWord* mem = NULL; 3405 3406 // If a chunk was available, add it to the in-use chunk list 3407 // and do an allocation from it. 3408 if (next != NULL) { 3409 // Add to this manager's list of chunks in use. 3410 // If the new chunk is humongous, it was created to serve a single large allocation. In that 3411 // case it usually makes no sense to make it the current chunk, since the next allocation would 3412 // need to allocate a new chunk anyway, while we would now prematurely retire a perfectly 3413 // good chunk which could be used for more normal allocations. 3414 bool make_current = true; 3415 if (next->get_chunk_type() == HumongousIndex && 3416 current_chunk() != NULL) { 3417 make_current = false; 3418 } 3419 add_chunk(next, make_current); 3420 mem = next->allocate(word_size); 3421 } 3422 3423 // Track metaspace memory usage statistic. 3424 track_metaspace_memory_usage(); 3425 3426 return mem; 3427 } 3428 3429 void SpaceManager::print_on(outputStream* st) const { 3430 3431 for (ChunkIndex i = ZeroIndex; 3432 i < NumberOfInUseLists ; 3433 i = next_chunk_index(i) ) { 3434 st->print_cr(" chunks_in_use " PTR_FORMAT " chunk size " SIZE_FORMAT, 3435 p2i(chunks_in_use(i)), 3436 chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size()); 3437 } 3438 st->print_cr(" waste: Small " SIZE_FORMAT " Medium " SIZE_FORMAT 3439 " Humongous " SIZE_FORMAT, 3440 sum_waste_in_chunks_in_use(SmallIndex), 3441 sum_waste_in_chunks_in_use(MediumIndex), 3442 sum_waste_in_chunks_in_use(HumongousIndex)); 3443 // block free lists 3444 if (block_freelists() != NULL) { 3445 st->print_cr("total in block free lists " SIZE_FORMAT, 3446 block_freelists()->total_size()); 3447 } 3448 } 3449 3450 SpaceManager::SpaceManager(Metaspace::MetadataType mdtype, 3451 Metaspace::MetaspaceType space_type, 3452 Mutex* lock) : 3453 _mdtype(mdtype), 3454 _space_type(space_type), 3455 _allocated_blocks_words(0), 3456 _allocated_chunks_words(0), 3457 _allocated_chunks_count(0), 3458 _block_freelists(NULL), 3459 _lock(lock) 3460 { 3461 initialize(); 3462 } 3463 3464 void SpaceManager::inc_size_metrics(size_t words) { 3465 assert_lock_strong(MetaspaceExpand_lock); 3466 // Total of allocated Metachunks and allocated Metachunks count 3467 // for each SpaceManager 3468 _allocated_chunks_words = _allocated_chunks_words + words; 3469 _allocated_chunks_count++; 3470 // Global total of capacity in allocated Metachunks 3471 MetaspaceUtils::inc_capacity(mdtype(), words); 3472 // Global total of allocated Metablocks. 3473 // used_words_slow() includes the overhead in each 3474 // Metachunk so include it in the used when the 3475 // Metachunk is first added (so only added once per 3476 // Metachunk). 3477 MetaspaceUtils::inc_used(mdtype(), Metachunk::overhead()); 3478 } 3479 3480 void SpaceManager::inc_used_metrics(size_t words) { 3481 // Add to the per SpaceManager total 3482 Atomic::add(words, &_allocated_blocks_words); 3483 // Add to the global total 3484 MetaspaceUtils::inc_used(mdtype(), words); 3485 } 3486 3487 void SpaceManager::dec_total_from_size_metrics() { 3488 MetaspaceUtils::dec_capacity(mdtype(), allocated_chunks_words()); 3489 MetaspaceUtils::dec_used(mdtype(), allocated_blocks_words()); 3490 // Also deduct the overhead per Metachunk 3491 MetaspaceUtils::dec_used(mdtype(), allocated_chunks_count() * Metachunk::overhead()); 3492 } 3493 3494 void SpaceManager::initialize() { 3495 Metadebug::init_allocation_fail_alot_count(); 3496 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 3497 _chunks_in_use[i] = NULL; 3498 } 3499 _current_chunk = NULL; 3500 log_trace(gc, metaspace, freelist)("SpaceManager(): " PTR_FORMAT, p2i(this)); 3501 } 3502 3503 SpaceManager::~SpaceManager() { 3504 // This call this->_lock which can't be done while holding MetaspaceExpand_lock 3505 assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(), 3506 "sum_capacity_in_chunks_in_use() " SIZE_FORMAT 3507 " allocated_chunks_words() " SIZE_FORMAT, 3508 sum_capacity_in_chunks_in_use(), allocated_chunks_words()); 3509 3510 MutexLockerEx fcl(MetaspaceExpand_lock, 3511 Mutex::_no_safepoint_check_flag); 3512 3513 assert(sum_count_in_chunks_in_use() == allocated_chunks_count(), 3514 "sum_count_in_chunks_in_use() " SIZE_FORMAT 3515 " allocated_chunks_count() " SIZE_FORMAT, 3516 sum_count_in_chunks_in_use(), allocated_chunks_count()); 3517 3518 chunk_manager()->slow_locked_verify(); 3519 3520 dec_total_from_size_metrics(); 3521 3522 Log(gc, metaspace, freelist) log; 3523 if (log.is_trace()) { 3524 log.trace("~SpaceManager(): " PTR_FORMAT, p2i(this)); 3525 ResourceMark rm; 3526 LogStream ls(log.trace()); 3527 locked_print_chunks_in_use_on(&ls); 3528 if (block_freelists() != NULL) { 3529 block_freelists()->print_on(&ls); 3530 } 3531 } 3532 3533 // Add all the chunks in use by this space manager 3534 // to the global list of free chunks. 3535 3536 // Follow each list of chunks-in-use and add them to the 3537 // free lists. Each list is NULL terminated. 3538 3539 for (ChunkIndex i = ZeroIndex; i <= HumongousIndex; i = next_chunk_index(i)) { 3540 Metachunk* chunks = chunks_in_use(i); 3541 chunk_manager()->return_chunk_list(i, chunks); 3542 set_chunks_in_use(i, NULL); 3543 } 3544 3545 chunk_manager()->slow_locked_verify(); 3546 3547 if (_block_freelists != NULL) { 3548 delete _block_freelists; 3549 } 3550 } 3551 3552 void SpaceManager::deallocate(MetaWord* p, size_t word_size) { 3553 assert_lock_strong(_lock); 3554 // Allocations and deallocations are in raw_word_size 3555 size_t raw_word_size = get_allocation_word_size(word_size); 3556 // Lazily create a block_freelist 3557 if (block_freelists() == NULL) { 3558 _block_freelists = new BlockFreelist(); 3559 } 3560 block_freelists()->return_block(p, raw_word_size); 3561 } 3562 3563 // Adds a chunk to the list of chunks in use. 3564 void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) { 3565 3566 assert_lock_strong(_lock); 3567 assert(new_chunk != NULL, "Should not be NULL"); 3568 assert(new_chunk->next() == NULL, "Should not be on a list"); 3569 3570 new_chunk->reset_empty(); 3571 3572 // Find the correct list and and set the current 3573 // chunk for that list. 3574 ChunkIndex index = chunk_manager()->list_index(new_chunk->word_size()); 3575 3576 if (make_current) { 3577 // If we are to make the chunk current, retire the old current chunk and replace 3578 // it with the new chunk. 3579 retire_current_chunk(); 3580 set_current_chunk(new_chunk); 3581 } 3582 3583 // Add the new chunk at the head of its respective chunk list. 3584 new_chunk->set_next(chunks_in_use(index)); 3585 set_chunks_in_use(index, new_chunk); 3586 3587 // Add to the running sum of capacity 3588 inc_size_metrics(new_chunk->word_size()); 3589 3590 assert(new_chunk->is_empty(), "Not ready for reuse"); 3591 Log(gc, metaspace, freelist) log; 3592 if (log.is_trace()) { 3593 log.trace("SpaceManager::add_chunk: " SIZE_FORMAT ") ", sum_count_in_chunks_in_use()); 3594 ResourceMark rm; 3595 LogStream ls(log.trace()); 3596 new_chunk->print_on(&ls); 3597 chunk_manager()->locked_print_free_chunks(&ls); 3598 } 3599 } 3600 3601 void SpaceManager::retire_current_chunk() { 3602 if (current_chunk() != NULL) { 3603 size_t remaining_words = current_chunk()->free_word_size(); 3604 if (remaining_words >= BlockFreelist::min_dictionary_size()) { 3605 MetaWord* ptr = current_chunk()->allocate(remaining_words); 3606 deallocate(ptr, remaining_words); 3607 inc_used_metrics(remaining_words); 3608 } 3609 } 3610 } 3611 3612 Metachunk* SpaceManager::get_new_chunk(size_t chunk_word_size) { 3613 // Get a chunk from the chunk freelist 3614 Metachunk* next = chunk_manager()->chunk_freelist_allocate(chunk_word_size); 3615 3616 if (next == NULL) { 3617 next = vs_list()->get_new_chunk(chunk_word_size, 3618 medium_chunk_bunch()); 3619 } 3620 3621 Log(gc, metaspace, alloc) log; 3622 if (log.is_debug() && next != NULL && 3623 SpaceManager::is_humongous(next->word_size())) { 3624 log.debug(" new humongous chunk word size " PTR_FORMAT, next->word_size()); 3625 } 3626 3627 return next; 3628 } 3629 3630 MetaWord* SpaceManager::allocate(size_t word_size) { 3631 MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); 3632 size_t raw_word_size = get_allocation_word_size(word_size); 3633 BlockFreelist* fl = block_freelists(); 3634 MetaWord* p = NULL; 3635 // Allocation from the dictionary is expensive in the sense that 3636 // the dictionary has to be searched for a size. Don't allocate 3637 // from the dictionary until it starts to get fat. Is this 3638 // a reasonable policy? Maybe an skinny dictionary is fast enough 3639 // for allocations. Do some profiling. JJJ 3640 if (fl != NULL && fl->total_size() > allocation_from_dictionary_limit) { 3641 p = fl->get_block(raw_word_size); 3642 } 3643 if (p == NULL) { 3644 p = allocate_work(raw_word_size); 3645 } 3646 3647 return p; 3648 } 3649 3650 // Returns the address of spaced allocated for "word_size". 3651 // This methods does not know about blocks (Metablocks) 3652 MetaWord* SpaceManager::allocate_work(size_t word_size) { 3653 assert_lock_strong(_lock); 3654 #ifdef ASSERT 3655 if (Metadebug::test_metadata_failure()) { 3656 return NULL; 3657 } 3658 #endif 3659 // Is there space in the current chunk? 3660 MetaWord* result = NULL; 3661 3662 if (current_chunk() != NULL) { 3663 result = current_chunk()->allocate(word_size); 3664 } 3665 3666 if (result == NULL) { 3667 result = grow_and_allocate(word_size); 3668 } 3669 3670 if (result != NULL) { 3671 inc_used_metrics(word_size); 3672 assert(result != (MetaWord*) chunks_in_use(MediumIndex), 3673 "Head of the list is being allocated"); 3674 } 3675 3676 return result; 3677 } 3678 3679 void SpaceManager::verify() { 3680 for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { 3681 Metachunk* curr = chunks_in_use(i); 3682 while (curr != NULL) { 3683 DEBUG_ONLY(do_verify_chunk(curr);) 3684 assert(curr->is_tagged_free() == false, "Chunk should be tagged as in use."); 3685 curr = curr->next(); 3686 } 3687 } 3688 } 3689 3690 void SpaceManager::verify_chunk_size(Metachunk* chunk) { 3691 assert(is_humongous(chunk->word_size()) || 3692 chunk->word_size() == medium_chunk_size() || 3693 chunk->word_size() == small_chunk_size() || 3694 chunk->word_size() == specialized_chunk_size(), 3695 "Chunk size is wrong"); 3696 return; 3697 } 3698 3699 #ifdef ASSERT 3700 void SpaceManager::verify_allocated_blocks_words() { 3701 // Verification is only guaranteed at a safepoint. 3702 assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(), 3703 "Verification can fail if the applications is running"); 3704 assert(allocated_blocks_words() == sum_used_in_chunks_in_use(), 3705 "allocation total is not consistent " SIZE_FORMAT 3706 " vs " SIZE_FORMAT, 3707 allocated_blocks_words(), sum_used_in_chunks_in_use()); 3708 } 3709 3710 #endif 3711 3712 void SpaceManager::dump(outputStream* const out) const { 3713 size_t curr_total = 0; 3714 size_t waste = 0; 3715 uint i = 0; 3716 size_t used = 0; 3717 size_t capacity = 0; 3718 3719 // Add up statistics for all chunks in this SpaceManager. 3720 for (ChunkIndex index = ZeroIndex; 3721 index < NumberOfInUseLists; 3722 index = next_chunk_index(index)) { 3723 for (Metachunk* curr = chunks_in_use(index); 3724 curr != NULL; 3725 curr = curr->next()) { 3726 out->print("%d) ", i++); 3727 curr->print_on(out); 3728 curr_total += curr->word_size(); 3729 used += curr->used_word_size(); 3730 capacity += curr->word_size(); 3731 waste += curr->free_word_size() + curr->overhead();; 3732 } 3733 } 3734 3735 if (log_is_enabled(Trace, gc, metaspace, freelist)) { 3736 if (block_freelists() != NULL) block_freelists()->print_on(out); 3737 } 3738 3739 size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size(); 3740 // Free space isn't wasted. 3741 waste -= free; 3742 3743 out->print_cr("total of all chunks " SIZE_FORMAT " used " SIZE_FORMAT 3744 " free " SIZE_FORMAT " capacity " SIZE_FORMAT 3745 " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste); 3746 } 3747 3748 // MetaspaceUtils 3749 3750 3751 size_t MetaspaceUtils::_capacity_words[] = {0, 0}; 3752 volatile size_t MetaspaceUtils::_used_words[] = {0, 0}; 3753 3754 size_t MetaspaceUtils::free_bytes(Metaspace::MetadataType mdtype) { 3755 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 3756 return list == NULL ? 0 : list->free_bytes(); 3757 } 3758 3759 size_t MetaspaceUtils::free_bytes() { 3760 return free_bytes(Metaspace::ClassType) + free_bytes(Metaspace::NonClassType); 3761 } 3762 3763 void MetaspaceUtils::dec_capacity(Metaspace::MetadataType mdtype, size_t words) { 3764 assert_lock_strong(MetaspaceExpand_lock); 3765 assert(words <= capacity_words(mdtype), 3766 "About to decrement below 0: words " SIZE_FORMAT 3767 " is greater than _capacity_words[%u] " SIZE_FORMAT, 3768 words, mdtype, capacity_words(mdtype)); 3769 _capacity_words[mdtype] -= words; 3770 } 3771 3772 void MetaspaceUtils::inc_capacity(Metaspace::MetadataType mdtype, size_t words) { 3773 assert_lock_strong(MetaspaceExpand_lock); 3774 // Needs to be atomic 3775 _capacity_words[mdtype] += words; 3776 } 3777 3778 void MetaspaceUtils::dec_used(Metaspace::MetadataType mdtype, size_t words) { 3779 assert(words <= used_words(mdtype), 3780 "About to decrement below 0: words " SIZE_FORMAT 3781 " is greater than _used_words[%u] " SIZE_FORMAT, 3782 words, mdtype, used_words(mdtype)); 3783 // For CMS deallocation of the Metaspaces occurs during the 3784 // sweep which is a concurrent phase. Protection by the MetaspaceExpand_lock 3785 // is not enough since allocation is on a per Metaspace basis 3786 // and protected by the Metaspace lock. 3787 Atomic::sub(words, &_used_words[mdtype]); 3788 } 3789 3790 void MetaspaceUtils::inc_used(Metaspace::MetadataType mdtype, size_t words) { 3791 // _used_words tracks allocations for 3792 // each piece of metadata. Those allocations are 3793 // generally done concurrently by different application 3794 // threads so must be done atomically. 3795 Atomic::add(words, &_used_words[mdtype]); 3796 } 3797 3798 size_t MetaspaceUtils::used_bytes_slow(Metaspace::MetadataType mdtype) { 3799 size_t used = 0; 3800 ClassLoaderDataGraphMetaspaceIterator iter; 3801 while (iter.repeat()) { 3802 ClassLoaderMetaspace* msp = iter.get_next(); 3803 // Sum allocated_blocks_words for each metaspace 3804 if (msp != NULL) { 3805 used += msp->used_words_slow(mdtype); 3806 } 3807 } 3808 return used * BytesPerWord; 3809 } 3810 3811 size_t MetaspaceUtils::free_bytes_slow(Metaspace::MetadataType mdtype) { 3812 size_t free = 0; 3813 ClassLoaderDataGraphMetaspaceIterator iter; 3814 while (iter.repeat()) { 3815 ClassLoaderMetaspace* msp = iter.get_next(); 3816 if (msp != NULL) { 3817 free += msp->free_words_slow(mdtype); 3818 } 3819 } 3820 return free * BytesPerWord; 3821 } 3822 3823 size_t MetaspaceUtils::capacity_bytes_slow(Metaspace::MetadataType mdtype) { 3824 if ((mdtype == Metaspace::ClassType) && !Metaspace::using_class_space()) { 3825 return 0; 3826 } 3827 // Don't count the space in the freelists. That space will be 3828 // added to the capacity calculation as needed. 3829 size_t capacity = 0; 3830 ClassLoaderDataGraphMetaspaceIterator iter; 3831 while (iter.repeat()) { 3832 ClassLoaderMetaspace* msp = iter.get_next(); 3833 if (msp != NULL) { 3834 capacity += msp->capacity_words_slow(mdtype); 3835 } 3836 } 3837 return capacity * BytesPerWord; 3838 } 3839 3840 size_t MetaspaceUtils::capacity_bytes_slow() { 3841 #ifdef PRODUCT 3842 // Use capacity_bytes() in PRODUCT instead of this function. 3843 guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT"); 3844 #endif 3845 size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType); 3846 size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType); 3847 assert(capacity_bytes() == class_capacity + non_class_capacity, 3848 "bad accounting: capacity_bytes() " SIZE_FORMAT 3849 " class_capacity + non_class_capacity " SIZE_FORMAT 3850 " class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT, 3851 capacity_bytes(), class_capacity + non_class_capacity, 3852 class_capacity, non_class_capacity); 3853 3854 return class_capacity + non_class_capacity; 3855 } 3856 3857 size_t MetaspaceUtils::reserved_bytes(Metaspace::MetadataType mdtype) { 3858 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 3859 return list == NULL ? 0 : list->reserved_bytes(); 3860 } 3861 3862 size_t MetaspaceUtils::committed_bytes(Metaspace::MetadataType mdtype) { 3863 VirtualSpaceList* list = Metaspace::get_space_list(mdtype); 3864 return list == NULL ? 0 : list->committed_bytes(); 3865 } 3866 3867 size_t MetaspaceUtils::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); } 3868 3869 size_t MetaspaceUtils::free_chunks_total_words(Metaspace::MetadataType mdtype) { 3870 ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype); 3871 if (chunk_manager == NULL) { 3872 return 0; 3873 } 3874 chunk_manager->slow_verify(); 3875 return chunk_manager->free_chunks_total_words(); 3876 } 3877 3878 size_t MetaspaceUtils::free_chunks_total_bytes(Metaspace::MetadataType mdtype) { 3879 return free_chunks_total_words(mdtype) * BytesPerWord; 3880 } 3881 3882 size_t MetaspaceUtils::free_chunks_total_words() { 3883 return free_chunks_total_words(Metaspace::ClassType) + 3884 free_chunks_total_words(Metaspace::NonClassType); 3885 } 3886 3887 size_t MetaspaceUtils::free_chunks_total_bytes() { 3888 return free_chunks_total_words() * BytesPerWord; 3889 } 3890 3891 bool MetaspaceUtils::has_chunk_free_list(Metaspace::MetadataType mdtype) { 3892 return Metaspace::get_chunk_manager(mdtype) != NULL; 3893 } 3894 3895 MetaspaceChunkFreeListSummary MetaspaceUtils::chunk_free_list_summary(Metaspace::MetadataType mdtype) { 3896 if (!has_chunk_free_list(mdtype)) { 3897 return MetaspaceChunkFreeListSummary(); 3898 } 3899 3900 const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype); 3901 return cm->chunk_free_list_summary(); 3902 } 3903 3904 void MetaspaceUtils::print_metaspace_change(size_t prev_metadata_used) { 3905 log_info(gc, metaspace)("Metaspace: " SIZE_FORMAT "K->" SIZE_FORMAT "K(" SIZE_FORMAT "K)", 3906 prev_metadata_used/K, used_bytes()/K, reserved_bytes()/K); 3907 } 3908 3909 void MetaspaceUtils::print_on(outputStream* out) { 3910 Metaspace::MetadataType nct = Metaspace::NonClassType; 3911 3912 out->print_cr(" Metaspace " 3913 "used " SIZE_FORMAT "K, " 3914 "capacity " SIZE_FORMAT "K, " 3915 "committed " SIZE_FORMAT "K, " 3916 "reserved " SIZE_FORMAT "K", 3917 used_bytes()/K, 3918 capacity_bytes()/K, 3919 committed_bytes()/K, 3920 reserved_bytes()/K); 3921 3922 if (Metaspace::using_class_space()) { 3923 Metaspace::MetadataType ct = Metaspace::ClassType; 3924 out->print_cr(" class space " 3925 "used " SIZE_FORMAT "K, " 3926 "capacity " SIZE_FORMAT "K, " 3927 "committed " SIZE_FORMAT "K, " 3928 "reserved " SIZE_FORMAT "K", 3929 used_bytes(ct)/K, 3930 capacity_bytes(ct)/K, 3931 committed_bytes(ct)/K, 3932 reserved_bytes(ct)/K); 3933 } 3934 } 3935 3936 // Print information for class space and data space separately. 3937 // This is almost the same as above. 3938 void MetaspaceUtils::print_on(outputStream* out, Metaspace::MetadataType mdtype) { 3939 size_t free_chunks_capacity_bytes = free_chunks_total_bytes(mdtype); 3940 size_t capacity_bytes = capacity_bytes_slow(mdtype); 3941 size_t used_bytes = used_bytes_slow(mdtype); 3942 size_t free_bytes = free_bytes_slow(mdtype); 3943 size_t used_and_free = used_bytes + free_bytes + 3944 free_chunks_capacity_bytes; 3945 out->print_cr(" Chunk accounting: (used in chunks " SIZE_FORMAT 3946 "K + unused in chunks " SIZE_FORMAT "K + " 3947 " capacity in free chunks " SIZE_FORMAT "K) = " SIZE_FORMAT 3948 "K capacity in allocated chunks " SIZE_FORMAT "K", 3949 used_bytes / K, 3950 free_bytes / K, 3951 free_chunks_capacity_bytes / K, 3952 used_and_free / K, 3953 capacity_bytes / K); 3954 // Accounting can only be correct if we got the values during a safepoint 3955 assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong"); 3956 } 3957 3958 // Print total fragmentation for class metaspaces 3959 void MetaspaceUtils::print_class_waste(outputStream* out) { 3960 assert(Metaspace::using_class_space(), "class metaspace not used"); 3961 size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0; 3962 size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_humongous_count = 0; 3963 ClassLoaderDataGraphMetaspaceIterator iter; 3964 while (iter.repeat()) { 3965 ClassLoaderMetaspace* msp = iter.get_next(); 3966 if (msp != NULL) { 3967 cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex); 3968 cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex); 3969 cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex); 3970 cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex); 3971 cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex); 3972 cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex); 3973 cls_humongous_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex); 3974 } 3975 } 3976 out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", " 3977 SIZE_FORMAT " small(s) " SIZE_FORMAT ", " 3978 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", " 3979 "large count " SIZE_FORMAT, 3980 cls_specialized_count, cls_specialized_waste, 3981 cls_small_count, cls_small_waste, 3982 cls_medium_count, cls_medium_waste, cls_humongous_count); 3983 } 3984 3985 // Print total fragmentation for data and class metaspaces separately 3986 void MetaspaceUtils::print_waste(outputStream* out) { 3987 size_t specialized_waste = 0, small_waste = 0, medium_waste = 0; 3988 size_t specialized_count = 0, small_count = 0, medium_count = 0, humongous_count = 0; 3989 3990 ClassLoaderDataGraphMetaspaceIterator iter; 3991 while (iter.repeat()) { 3992 ClassLoaderMetaspace* msp = iter.get_next(); 3993 if (msp != NULL) { 3994 specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex); 3995 specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex); 3996 small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex); 3997 small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex); 3998 medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex); 3999 medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex); 4000 humongous_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex); 4001 } 4002 } 4003 out->print_cr("Total fragmentation waste (words) doesn't count free space"); 4004 out->print_cr(" data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", " 4005 SIZE_FORMAT " small(s) " SIZE_FORMAT ", " 4006 SIZE_FORMAT " medium(s) " SIZE_FORMAT ", " 4007 "large count " SIZE_FORMAT, 4008 specialized_count, specialized_waste, small_count, 4009 small_waste, medium_count, medium_waste, humongous_count); 4010 if (Metaspace::using_class_space()) { 4011 print_class_waste(out); 4012 } 4013 } 4014 4015 class MetadataStats { 4016 private: 4017 size_t _capacity; 4018 size_t _used; 4019 size_t _free; 4020 size_t _waste; 4021 4022 public: 4023 MetadataStats() : _capacity(0), _used(0), _free(0), _waste(0) { } 4024 MetadataStats(size_t capacity, size_t used, size_t free, size_t waste) 4025 : _capacity(capacity), _used(used), _free(free), _waste(waste) { } 4026 4027 void add(const MetadataStats& stats) { 4028 _capacity += stats.capacity(); 4029 _used += stats.used(); 4030 _free += stats.free(); 4031 _waste += stats.waste(); 4032 } 4033 4034 size_t capacity() const { return _capacity; } 4035 size_t used() const { return _used; } 4036 size_t free() const { return _free; } 4037 size_t waste() const { return _waste; } 4038 4039 void print_on(outputStream* out, size_t scale) const; 4040 }; 4041 4042 4043 void MetadataStats::print_on(outputStream* out, size_t scale) const { 4044 const char* unit = scale_unit(scale); 4045 out->print_cr("capacity=%10.2f%s used=%10.2f%s free=%10.2f%s waste=%10.2f%s", 4046 (float)capacity() / scale, unit, 4047 (float)used() / scale, unit, 4048 (float)free() / scale, unit, 4049 (float)waste() / scale, unit); 4050 } 4051 4052 class PrintCLDMetaspaceInfoClosure : public CLDClosure { 4053 private: 4054 outputStream* _out; 4055 size_t _scale; 4056 4057 size_t _total_count; 4058 MetadataStats _total_metadata; 4059 MetadataStats _total_class; 4060 4061 size_t _total_anon_count; 4062 MetadataStats _total_anon_metadata; 4063 MetadataStats _total_anon_class; 4064 4065 public: 4066 PrintCLDMetaspaceInfoClosure(outputStream* out, size_t scale = K) 4067 : _out(out), _scale(scale), _total_count(0), _total_anon_count(0) { } 4068 4069 ~PrintCLDMetaspaceInfoClosure() { 4070 print_summary(); 4071 } 4072 4073 void do_cld(ClassLoaderData* cld) { 4074 assert(SafepointSynchronize::is_at_safepoint(), "Must be at a safepoint"); 4075 4076 if (cld->is_unloading()) return; 4077 ClassLoaderMetaspace* msp = cld->metaspace_or_null(); 4078 if (msp == NULL) { 4079 return; 4080 } 4081 4082 bool anonymous = false; 4083 if (cld->is_anonymous()) { 4084 _out->print_cr("ClassLoader: for anonymous class"); 4085 anonymous = true; 4086 } else { 4087 ResourceMark rm; 4088 _out->print_cr("ClassLoader: %s", cld->loader_name()); 4089 } 4090 4091 print_metaspace(msp, anonymous); 4092 _out->cr(); 4093 } 4094 4095 private: 4096 void print_metaspace(ClassLoaderMetaspace* msp, bool anonymous); 4097 void print_summary() const; 4098 }; 4099 4100 void PrintCLDMetaspaceInfoClosure::print_metaspace(ClassLoaderMetaspace* msp, bool anonymous){ 4101 assert(msp != NULL, "Sanity"); 4102 SpaceManager* vsm = msp->vsm(); 4103 const char* unit = scale_unit(_scale); 4104 4105 size_t capacity = vsm->sum_capacity_in_chunks_in_use() * BytesPerWord; 4106 size_t used = vsm->sum_used_in_chunks_in_use() * BytesPerWord; 4107 size_t free = vsm->sum_free_in_chunks_in_use() * BytesPerWord; 4108 size_t waste = vsm->sum_waste_in_chunks_in_use() * BytesPerWord; 4109 4110 _total_count ++; 4111 MetadataStats metadata_stats(capacity, used, free, waste); 4112 _total_metadata.add(metadata_stats); 4113 4114 if (anonymous) { 4115 _total_anon_count ++; 4116 _total_anon_metadata.add(metadata_stats); 4117 } 4118 4119 _out->print(" Metadata "); 4120 metadata_stats.print_on(_out, _scale); 4121 4122 if (Metaspace::using_class_space()) { 4123 vsm = msp->class_vsm(); 4124 4125 capacity = vsm->sum_capacity_in_chunks_in_use() * BytesPerWord; 4126 used = vsm->sum_used_in_chunks_in_use() * BytesPerWord; 4127 free = vsm->sum_free_in_chunks_in_use() * BytesPerWord; 4128 waste = vsm->sum_waste_in_chunks_in_use() * BytesPerWord; 4129 4130 MetadataStats class_stats(capacity, used, free, waste); 4131 _total_class.add(class_stats); 4132 4133 if (anonymous) { 4134 _total_anon_class.add(class_stats); 4135 } 4136 4137 _out->print(" Class data "); 4138 class_stats.print_on(_out, _scale); 4139 } 4140 } 4141 4142 void PrintCLDMetaspaceInfoClosure::print_summary() const { 4143 const char* unit = scale_unit(_scale); 4144 _out->cr(); 4145 _out->print_cr("Summary:"); 4146 4147 MetadataStats total; 4148 total.add(_total_metadata); 4149 total.add(_total_class); 4150 4151 _out->print(" Total class loaders=" SIZE_FORMAT_W(6) " ", _total_count); 4152 total.print_on(_out, _scale); 4153 4154 _out->print(" Metadata "); 4155 _total_metadata.print_on(_out, _scale); 4156 4157 if (Metaspace::using_class_space()) { 4158 _out->print(" Class data "); 4159 _total_class.print_on(_out, _scale); 4160 } 4161 _out->cr(); 4162 4163 MetadataStats total_anon; 4164 total_anon.add(_total_anon_metadata); 4165 total_anon.add(_total_anon_class); 4166 4167 _out->print("For anonymous classes=" SIZE_FORMAT_W(6) " ", _total_anon_count); 4168 total_anon.print_on(_out, _scale); 4169 4170 _out->print(" Metadata "); 4171 _total_anon_metadata.print_on(_out, _scale); 4172 4173 if (Metaspace::using_class_space()) { 4174 _out->print(" Class data "); 4175 _total_anon_class.print_on(_out, _scale); 4176 } 4177 } 4178 4179 void MetaspaceUtils::print_metadata_for_nmt(outputStream* out, size_t scale) { 4180 const char* unit = scale_unit(scale); 4181 out->print_cr("Metaspaces:"); 4182 out->print_cr(" Metadata space: reserved=" SIZE_FORMAT_W(10) "%s committed=" SIZE_FORMAT_W(10) "%s", 4183 reserved_bytes(Metaspace::NonClassType) / scale, unit, 4184 committed_bytes(Metaspace::NonClassType) / scale, unit); 4185 if (Metaspace::using_class_space()) { 4186 out->print_cr(" Class space: reserved=" SIZE_FORMAT_W(10) "%s committed=" SIZE_FORMAT_W(10) "%s", 4187 reserved_bytes(Metaspace::ClassType) / scale, unit, 4188 committed_bytes(Metaspace::ClassType) / scale, unit); 4189 } 4190 4191 out->cr(); 4192 ChunkManager::print_all_chunkmanagers(out, scale); 4193 4194 out->cr(); 4195 out->print_cr("Per-classloader metadata:"); 4196 out->cr(); 4197 4198 PrintCLDMetaspaceInfoClosure cl(out, scale); 4199 ClassLoaderDataGraph::cld_do(&cl); 4200 } 4201 4202 4203 // Dump global metaspace things from the end of ClassLoaderDataGraph 4204 void MetaspaceUtils::dump(outputStream* out) { 4205 out->print_cr("All Metaspace:"); 4206 out->print("data space: "); print_on(out, Metaspace::NonClassType); 4207 out->print("class space: "); print_on(out, Metaspace::ClassType); 4208 print_waste(out); 4209 } 4210 4211 // Prints an ASCII representation of the given space. 4212 void MetaspaceUtils::print_metaspace_map(outputStream* out, Metaspace::MetadataType mdtype) { 4213 MutexLockerEx cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag); 4214 const bool for_class = mdtype == Metaspace::ClassType ? true : false; 4215 VirtualSpaceList* const vsl = for_class ? Metaspace::class_space_list() : Metaspace::space_list(); 4216 if (vsl != NULL) { 4217 if (for_class) { 4218 if (!Metaspace::using_class_space()) { 4219 out->print_cr("No Class Space."); 4220 return; 4221 } 4222 out->print_raw("---- Metaspace Map (Class Space) ----"); 4223 } else { 4224 out->print_raw("---- Metaspace Map (Non-Class Space) ----"); 4225 } 4226 // Print legend: 4227 out->cr(); 4228 out->print_cr("Chunk Types (uppercase chunks are in use): x-specialized, s-small, m-medium, h-humongous."); 4229 out->cr(); 4230 VirtualSpaceList* const vsl = for_class ? Metaspace::class_space_list() : Metaspace::space_list(); 4231 vsl->print_map(out); 4232 out->cr(); 4233 } 4234 } 4235 4236 void MetaspaceUtils::verify_free_chunks() { 4237 Metaspace::chunk_manager_metadata()->verify(); 4238 if (Metaspace::using_class_space()) { 4239 Metaspace::chunk_manager_class()->verify(); 4240 } 4241 } 4242 4243 void MetaspaceUtils::verify_capacity() { 4244 #ifdef ASSERT 4245 size_t running_sum_capacity_bytes = capacity_bytes(); 4246 // For purposes of the running sum of capacity, verify against capacity 4247 size_t capacity_in_use_bytes = capacity_bytes_slow(); 4248 assert(running_sum_capacity_bytes == capacity_in_use_bytes, 4249 "capacity_words() * BytesPerWord " SIZE_FORMAT 4250 " capacity_bytes_slow()" SIZE_FORMAT, 4251 running_sum_capacity_bytes, capacity_in_use_bytes); 4252 for (Metaspace::MetadataType i = Metaspace::ClassType; 4253 i < Metaspace:: MetadataTypeCount; 4254 i = (Metaspace::MetadataType)(i + 1)) { 4255 size_t capacity_in_use_bytes = capacity_bytes_slow(i); 4256 assert(capacity_bytes(i) == capacity_in_use_bytes, 4257 "capacity_bytes(%u) " SIZE_FORMAT 4258 " capacity_bytes_slow(%u)" SIZE_FORMAT, 4259 i, capacity_bytes(i), i, capacity_in_use_bytes); 4260 } 4261 #endif 4262 } 4263 4264 void MetaspaceUtils::verify_used() { 4265 #ifdef ASSERT 4266 size_t running_sum_used_bytes = used_bytes(); 4267 // For purposes of the running sum of used, verify against used 4268 size_t used_in_use_bytes = used_bytes_slow(); 4269 assert(used_bytes() == used_in_use_bytes, 4270 "used_bytes() " SIZE_FORMAT 4271 " used_bytes_slow()" SIZE_FORMAT, 4272 used_bytes(), used_in_use_bytes); 4273 for (Metaspace::MetadataType i = Metaspace::ClassType; 4274 i < Metaspace:: MetadataTypeCount; 4275 i = (Metaspace::MetadataType)(i + 1)) { 4276 size_t used_in_use_bytes = used_bytes_slow(i); 4277 assert(used_bytes(i) == used_in_use_bytes, 4278 "used_bytes(%u) " SIZE_FORMAT 4279 " used_bytes_slow(%u)" SIZE_FORMAT, 4280 i, used_bytes(i), i, used_in_use_bytes); 4281 } 4282 #endif 4283 } 4284 4285 void MetaspaceUtils::verify_metrics() { 4286 verify_capacity(); 4287 verify_used(); 4288 } 4289 4290 4291 // Metaspace methods 4292 4293 size_t Metaspace::_first_chunk_word_size = 0; 4294 size_t Metaspace::_first_class_chunk_word_size = 0; 4295 4296 size_t Metaspace::_commit_alignment = 0; 4297 size_t Metaspace::_reserve_alignment = 0; 4298 4299 VirtualSpaceList* Metaspace::_space_list = NULL; 4300 VirtualSpaceList* Metaspace::_class_space_list = NULL; 4301 4302 ChunkManager* Metaspace::_chunk_manager_metadata = NULL; 4303 ChunkManager* Metaspace::_chunk_manager_class = NULL; 4304 4305 #define VIRTUALSPACEMULTIPLIER 2 4306 4307 #ifdef _LP64 4308 static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1); 4309 4310 void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) { 4311 assert(!DumpSharedSpaces, "narrow_klass is set by MetaspaceShared class."); 4312 // Figure out the narrow_klass_base and the narrow_klass_shift. The 4313 // narrow_klass_base is the lower of the metaspace base and the cds base 4314 // (if cds is enabled). The narrow_klass_shift depends on the distance 4315 // between the lower base and higher address. 4316 address lower_base; 4317 address higher_address; 4318 #if INCLUDE_CDS 4319 if (UseSharedSpaces) { 4320 higher_address = MAX2((address)(cds_base + MetaspaceShared::core_spaces_size()), 4321 (address)(metaspace_base + compressed_class_space_size())); 4322 lower_base = MIN2(metaspace_base, cds_base); 4323 } else 4324 #endif 4325 { 4326 higher_address = metaspace_base + compressed_class_space_size(); 4327 lower_base = metaspace_base; 4328 4329 uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes; 4330 // If compressed class space fits in lower 32G, we don't need a base. 4331 if (higher_address <= (address)klass_encoding_max) { 4332 lower_base = 0; // Effectively lower base is zero. 4333 } 4334 } 4335 4336 Universe::set_narrow_klass_base(lower_base); 4337 4338 // CDS uses LogKlassAlignmentInBytes for narrow_klass_shift. See 4339 // MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() for 4340 // how dump time narrow_klass_shift is set. Although, CDS can work 4341 // with zero-shift mode also, to be consistent with AOT it uses 4342 // LogKlassAlignmentInBytes for klass shift so archived java heap objects 4343 // can be used at same time as AOT code. 4344 if (!UseSharedSpaces 4345 && (uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) { 4346 Universe::set_narrow_klass_shift(0); 4347 } else { 4348 Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes); 4349 } 4350 AOTLoader::set_narrow_klass_shift(); 4351 } 4352 4353 #if INCLUDE_CDS 4354 // Return TRUE if the specified metaspace_base and cds_base are close enough 4355 // to work with compressed klass pointers. 4356 bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) { 4357 assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS"); 4358 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); 4359 address lower_base = MIN2((address)metaspace_base, cds_base); 4360 address higher_address = MAX2((address)(cds_base + MetaspaceShared::core_spaces_size()), 4361 (address)(metaspace_base + compressed_class_space_size())); 4362 return ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax); 4363 } 4364 #endif 4365 4366 // Try to allocate the metaspace at the requested addr. 4367 void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) { 4368 assert(!DumpSharedSpaces, "compress klass space is allocated by MetaspaceShared class."); 4369 assert(using_class_space(), "called improperly"); 4370 assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); 4371 assert(compressed_class_space_size() < KlassEncodingMetaspaceMax, 4372 "Metaspace size is too big"); 4373 assert_is_aligned(requested_addr, _reserve_alignment); 4374 assert_is_aligned(cds_base, _reserve_alignment); 4375 assert_is_aligned(compressed_class_space_size(), _reserve_alignment); 4376 4377 // Don't use large pages for the class space. 4378 bool large_pages = false; 4379 4380 #if !(defined(AARCH64) || defined(AIX)) 4381 ReservedSpace metaspace_rs = ReservedSpace(compressed_class_space_size(), 4382 _reserve_alignment, 4383 large_pages, 4384 requested_addr); 4385 #else // AARCH64 4386 ReservedSpace metaspace_rs; 4387 4388 // Our compressed klass pointers may fit nicely into the lower 32 4389 // bits. 4390 if ((uint64_t)requested_addr + compressed_class_space_size() < 4*G) { 4391 metaspace_rs = ReservedSpace(compressed_class_space_size(), 4392 _reserve_alignment, 4393 large_pages, 4394 requested_addr); 4395 } 4396 4397 if (! metaspace_rs.is_reserved()) { 4398 // Aarch64: Try to align metaspace so that we can decode a compressed 4399 // klass with a single MOVK instruction. We can do this iff the 4400 // compressed class base is a multiple of 4G. 4401 // Aix: Search for a place where we can find memory. If we need to load 4402 // the base, 4G alignment is helpful, too. 4403 size_t increment = AARCH64_ONLY(4*)G; 4404 for (char *a = align_up(requested_addr, increment); 4405 a < (char*)(1024*G); 4406 a += increment) { 4407 if (a == (char *)(32*G)) { 4408 // Go faster from here on. Zero-based is no longer possible. 4409 increment = 4*G; 4410 } 4411 4412 #if INCLUDE_CDS 4413 if (UseSharedSpaces 4414 && ! can_use_cds_with_metaspace_addr(a, cds_base)) { 4415 // We failed to find an aligned base that will reach. Fall 4416 // back to using our requested addr. 4417 metaspace_rs = ReservedSpace(compressed_class_space_size(), 4418 _reserve_alignment, 4419 large_pages, 4420 requested_addr); 4421 break; 4422 } 4423 #endif 4424 4425 metaspace_rs = ReservedSpace(compressed_class_space_size(), 4426 _reserve_alignment, 4427 large_pages, 4428 a); 4429 if (metaspace_rs.is_reserved()) 4430 break; 4431 } 4432 } 4433 4434 #endif // AARCH64 4435 4436 if (!metaspace_rs.is_reserved()) { 4437 #if INCLUDE_CDS 4438 if (UseSharedSpaces) { 4439 size_t increment = align_up(1*G, _reserve_alignment); 4440 4441 // Keep trying to allocate the metaspace, increasing the requested_addr 4442 // by 1GB each time, until we reach an address that will no longer allow 4443 // use of CDS with compressed klass pointers. 4444 char *addr = requested_addr; 4445 while (!metaspace_rs.is_reserved() && (addr + increment > addr) && 4446 can_use_cds_with_metaspace_addr(addr + increment, cds_base)) { 4447 addr = addr + increment; 4448 metaspace_rs = ReservedSpace(compressed_class_space_size(), 4449 _reserve_alignment, large_pages, addr); 4450 } 4451 } 4452 #endif 4453 // If no successful allocation then try to allocate the space anywhere. If 4454 // that fails then OOM doom. At this point we cannot try allocating the 4455 // metaspace as if UseCompressedClassPointers is off because too much 4456 // initialization has happened that depends on UseCompressedClassPointers. 4457 // So, UseCompressedClassPointers cannot be turned off at this point. 4458 if (!metaspace_rs.is_reserved()) { 4459 metaspace_rs = ReservedSpace(compressed_class_space_size(), 4460 _reserve_alignment, large_pages); 4461 if (!metaspace_rs.is_reserved()) { 4462 vm_exit_during_initialization(err_msg("Could not allocate metaspace: " SIZE_FORMAT " bytes", 4463 compressed_class_space_size())); 4464 } 4465 } 4466 } 4467 4468 // If we got here then the metaspace got allocated. 4469 MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass); 4470 4471 #if INCLUDE_CDS 4472 // Verify that we can use shared spaces. Otherwise, turn off CDS. 4473 if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) { 4474 FileMapInfo::stop_sharing_and_unmap( 4475 "Could not allocate metaspace at a compatible address"); 4476 } 4477 #endif 4478 set_narrow_klass_base_and_shift((address)metaspace_rs.base(), 4479 UseSharedSpaces ? (address)cds_base : 0); 4480 4481 initialize_class_space(metaspace_rs); 4482 4483 LogTarget(Trace, gc, metaspace) lt; 4484 if (lt.is_enabled()) { 4485 ResourceMark rm; 4486 LogStream ls(lt); 4487 print_compressed_class_space(&ls, requested_addr); 4488 } 4489 } 4490 4491 void Metaspace::print_compressed_class_space(outputStream* st, const char* requested_addr) { 4492 st->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: %d", 4493 p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift()); 4494 if (_class_space_list != NULL) { 4495 address base = (address)_class_space_list->current_virtual_space()->bottom(); 4496 st->print("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT, 4497 compressed_class_space_size(), p2i(base)); 4498 if (requested_addr != 0) { 4499 st->print(" Req Addr: " PTR_FORMAT, p2i(requested_addr)); 4500 } 4501 st->cr(); 4502 } 4503 } 4504 4505 // For UseCompressedClassPointers the class space is reserved above the top of 4506 // the Java heap. The argument passed in is at the base of the compressed space. 4507 void Metaspace::initialize_class_space(ReservedSpace rs) { 4508 // The reserved space size may be bigger because of alignment, esp with UseLargePages 4509 assert(rs.size() >= CompressedClassSpaceSize, 4510 SIZE_FORMAT " != " SIZE_FORMAT, rs.size(), CompressedClassSpaceSize); 4511 assert(using_class_space(), "Must be using class space"); 4512 _class_space_list = new VirtualSpaceList(rs); 4513 _chunk_manager_class = new ChunkManager(true/*is_class*/); 4514 4515 if (!_class_space_list->initialization_succeeded()) { 4516 vm_exit_during_initialization("Failed to setup compressed class space virtual space list."); 4517 } 4518 } 4519 4520 #endif 4521 4522 void Metaspace::ergo_initialize() { 4523 if (DumpSharedSpaces) { 4524 // Using large pages when dumping the shared archive is currently not implemented. 4525 FLAG_SET_ERGO(bool, UseLargePagesInMetaspace, false); 4526 } 4527 4528 size_t page_size = os::vm_page_size(); 4529 if (UseLargePages && UseLargePagesInMetaspace) { 4530 page_size = os::large_page_size(); 4531 } 4532 4533 _commit_alignment = page_size; 4534 _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity()); 4535 4536 // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will 4537 // override if MaxMetaspaceSize was set on the command line or not. 4538 // This information is needed later to conform to the specification of the 4539 // java.lang.management.MemoryUsage API. 4540 // 4541 // Ideally, we would be able to set the default value of MaxMetaspaceSize in 4542 // globals.hpp to the aligned value, but this is not possible, since the 4543 // alignment depends on other flags being parsed. 4544 MaxMetaspaceSize = align_down_bounded(MaxMetaspaceSize, _reserve_alignment); 4545 4546 if (MetaspaceSize > MaxMetaspaceSize) { 4547 MetaspaceSize = MaxMetaspaceSize; 4548 } 4549 4550 MetaspaceSize = align_down_bounded(MetaspaceSize, _commit_alignment); 4551 4552 assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize"); 4553 4554 MinMetaspaceExpansion = align_down_bounded(MinMetaspaceExpansion, _commit_alignment); 4555 MaxMetaspaceExpansion = align_down_bounded(MaxMetaspaceExpansion, _commit_alignment); 4556 4557 CompressedClassSpaceSize = align_down_bounded(CompressedClassSpaceSize, _reserve_alignment); 4558 4559 // Initial virtual space size will be calculated at global_initialize() 4560 size_t min_metaspace_sz = 4561 VIRTUALSPACEMULTIPLIER * InitialBootClassLoaderMetaspaceSize; 4562 if (UseCompressedClassPointers) { 4563 if ((min_metaspace_sz + CompressedClassSpaceSize) > MaxMetaspaceSize) { 4564 if (min_metaspace_sz >= MaxMetaspaceSize) { 4565 vm_exit_during_initialization("MaxMetaspaceSize is too small."); 4566 } else { 4567 FLAG_SET_ERGO(size_t, CompressedClassSpaceSize, 4568 MaxMetaspaceSize - min_metaspace_sz); 4569 } 4570 } 4571 } else if (min_metaspace_sz >= MaxMetaspaceSize) { 4572 FLAG_SET_ERGO(size_t, InitialBootClassLoaderMetaspaceSize, 4573 min_metaspace_sz); 4574 } 4575 4576 set_compressed_class_space_size(CompressedClassSpaceSize); 4577 } 4578 4579 void Metaspace::global_initialize() { 4580 MetaspaceGC::initialize(); 4581 4582 #if INCLUDE_CDS 4583 if (DumpSharedSpaces) { 4584 MetaspaceShared::initialize_dumptime_shared_and_meta_spaces(); 4585 } else if (UseSharedSpaces) { 4586 // If any of the archived space fails to map, UseSharedSpaces 4587 // is reset to false. Fall through to the 4588 // (!DumpSharedSpaces && !UseSharedSpaces) case to set up class 4589 // metaspace. 4590 MetaspaceShared::initialize_runtime_shared_and_meta_spaces(); 4591 } 4592 4593 if (!DumpSharedSpaces && !UseSharedSpaces) 4594 #endif // INCLUDE_CDS 4595 { 4596 #ifdef _LP64 4597 if (using_class_space()) { 4598 char* base = (char*)align_up(Universe::heap()->reserved_region().end(), _reserve_alignment); 4599 allocate_metaspace_compressed_klass_ptrs(base, 0); 4600 } 4601 #endif // _LP64 4602 } 4603 4604 // Initialize these before initializing the VirtualSpaceList 4605 _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord; 4606 _first_chunk_word_size = align_word_size_up(_first_chunk_word_size); 4607 // Make the first class chunk bigger than a medium chunk so it's not put 4608 // on the medium chunk list. The next chunk will be small and progress 4609 // from there. This size calculated by -version. 4610 _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6, 4611 (CompressedClassSpaceSize/BytesPerWord)*2); 4612 _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size); 4613 // Arbitrarily set the initial virtual space to a multiple 4614 // of the boot class loader size. 4615 size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size; 4616 word_size = align_up(word_size, Metaspace::reserve_alignment_words()); 4617 4618 // Initialize the list of virtual spaces. 4619 _space_list = new VirtualSpaceList(word_size); 4620 _chunk_manager_metadata = new ChunkManager(false/*metaspace*/); 4621 4622 if (!_space_list->initialization_succeeded()) { 4623 vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL); 4624 } 4625 4626 _tracer = new MetaspaceTracer(); 4627 } 4628 4629 void Metaspace::post_initialize() { 4630 MetaspaceGC::post_initialize(); 4631 } 4632 4633 void Metaspace::verify_global_initialization() { 4634 assert(space_list() != NULL, "Metadata VirtualSpaceList has not been initialized"); 4635 assert(chunk_manager_metadata() != NULL, "Metadata ChunkManager has not been initialized"); 4636 4637 if (using_class_space()) { 4638 assert(class_space_list() != NULL, "Class VirtualSpaceList has not been initialized"); 4639 assert(chunk_manager_class() != NULL, "Class ChunkManager has not been initialized"); 4640 } 4641 } 4642 4643 size_t Metaspace::align_word_size_up(size_t word_size) { 4644 size_t byte_size = word_size * wordSize; 4645 return ReservedSpace::allocation_align_size_up(byte_size) / wordSize; 4646 } 4647 4648 MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size, 4649 MetaspaceObj::Type type, TRAPS) { 4650 assert(!_frozen, "sanity"); 4651 if (HAS_PENDING_EXCEPTION) { 4652 assert(false, "Should not allocate with exception pending"); 4653 return NULL; // caller does a CHECK_NULL too 4654 } 4655 4656 assert(loader_data != NULL, "Should never pass around a NULL loader_data. " 4657 "ClassLoaderData::the_null_class_loader_data() should have been used."); 4658 4659 MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType; 4660 4661 // Try to allocate metadata. 4662 MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype); 4663 4664 if (result == NULL) { 4665 tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype); 4666 4667 // Allocation failed. 4668 if (is_init_completed() && !(DumpSharedSpaces && THREAD->is_VM_thread())) { 4669 // Only start a GC if the bootstrapping has completed. 4670 // Also, we cannot GC if we are at the end of the CDS dumping stage which runs inside 4671 // the VM thread. 4672 4673 // Try to clean out some memory and retry. 4674 result = Universe::heap()->satisfy_failed_metadata_allocation(loader_data, word_size, mdtype); 4675 } 4676 } 4677 4678 if (result == NULL) { 4679 if (DumpSharedSpaces) { 4680 // CDS dumping keeps loading classes, so if we hit an OOM we probably will keep hitting OOM. 4681 // We should abort to avoid generating a potentially bad archive. 4682 tty->print_cr("Failed allocating metaspace object type %s of size " SIZE_FORMAT ". CDS dump aborted.", 4683 MetaspaceObj::type_name(type), word_size * BytesPerWord); 4684 tty->print_cr("Please increase MaxMetaspaceSize (currently " SIZE_FORMAT " bytes).", MaxMetaspaceSize); 4685 vm_exit(1); 4686 } 4687 report_metadata_oome(loader_data, word_size, type, mdtype, CHECK_NULL); 4688 } 4689 4690 // Zero initialize. 4691 Copy::fill_to_words((HeapWord*)result, word_size, 0); 4692 4693 return result; 4694 } 4695 4696 void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) { 4697 tracer()->report_metadata_oom(loader_data, word_size, type, mdtype); 4698 4699 // If result is still null, we are out of memory. 4700 Log(gc, metaspace, freelist) log; 4701 if (log.is_info()) { 4702 log.info("Metaspace (%s) allocation failed for size " SIZE_FORMAT, 4703 is_class_space_allocation(mdtype) ? "class" : "data", word_size); 4704 ResourceMark rm; 4705 if (log.is_debug()) { 4706 if (loader_data->metaspace_or_null() != NULL) { 4707 LogStream ls(log.debug()); 4708 loader_data->print_value_on(&ls); 4709 } 4710 } 4711 LogStream ls(log.info()); 4712 MetaspaceUtils::dump(&ls); 4713 MetaspaceUtils::print_metaspace_map(&ls, mdtype); 4714 ChunkManager::print_all_chunkmanagers(&ls); 4715 } 4716 4717 bool out_of_compressed_class_space = false; 4718 if (is_class_space_allocation(mdtype)) { 4719 ClassLoaderMetaspace* metaspace = loader_data->metaspace_non_null(); 4720 out_of_compressed_class_space = 4721 MetaspaceUtils::committed_bytes(Metaspace::ClassType) + 4722 (metaspace->class_chunk_size(word_size) * BytesPerWord) > 4723 CompressedClassSpaceSize; 4724 } 4725 4726 // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support 4727 const char* space_string = out_of_compressed_class_space ? 4728 "Compressed class space" : "Metaspace"; 4729 4730 report_java_out_of_memory(space_string); 4731 4732 if (JvmtiExport::should_post_resource_exhausted()) { 4733 JvmtiExport::post_resource_exhausted( 4734 JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR, 4735 space_string); 4736 } 4737 4738 if (!is_init_completed()) { 4739 vm_exit_during_initialization("OutOfMemoryError", space_string); 4740 } 4741 4742 if (out_of_compressed_class_space) { 4743 THROW_OOP(Universe::out_of_memory_error_class_metaspace()); 4744 } else { 4745 THROW_OOP(Universe::out_of_memory_error_metaspace()); 4746 } 4747 } 4748 4749 const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) { 4750 switch (mdtype) { 4751 case Metaspace::ClassType: return "Class"; 4752 case Metaspace::NonClassType: return "Metadata"; 4753 default: 4754 assert(false, "Got bad mdtype: %d", (int) mdtype); 4755 return NULL; 4756 } 4757 } 4758 4759 void Metaspace::purge(MetadataType mdtype) { 4760 get_space_list(mdtype)->purge(get_chunk_manager(mdtype)); 4761 } 4762 4763 void Metaspace::purge() { 4764 MutexLockerEx cl(MetaspaceExpand_lock, 4765 Mutex::_no_safepoint_check_flag); 4766 purge(NonClassType); 4767 if (using_class_space()) { 4768 purge(ClassType); 4769 } 4770 } 4771 4772 bool Metaspace::contains(const void* ptr) { 4773 if (MetaspaceShared::is_in_shared_metaspace(ptr)) { 4774 return true; 4775 } 4776 return contains_non_shared(ptr); 4777 } 4778 4779 bool Metaspace::contains_non_shared(const void* ptr) { 4780 if (using_class_space() && get_space_list(ClassType)->contains(ptr)) { 4781 return true; 4782 } 4783 4784 return get_space_list(NonClassType)->contains(ptr); 4785 } 4786 4787 // ClassLoaderMetaspace 4788 4789 ClassLoaderMetaspace::ClassLoaderMetaspace(Mutex* lock, Metaspace::MetaspaceType type) { 4790 initialize(lock, type); 4791 } 4792 4793 ClassLoaderMetaspace::~ClassLoaderMetaspace() { 4794 delete _vsm; 4795 if (Metaspace::using_class_space()) { 4796 delete _class_vsm; 4797 } 4798 } 4799 void ClassLoaderMetaspace::initialize_first_chunk(Metaspace::MetaspaceType type, Metaspace::MetadataType mdtype) { 4800 Metachunk* chunk = get_initialization_chunk(type, mdtype); 4801 if (chunk != NULL) { 4802 // Add to this manager's list of chunks in use and make it the current_chunk(). 4803 get_space_manager(mdtype)->add_chunk(chunk, true); 4804 } 4805 } 4806 4807 Metachunk* ClassLoaderMetaspace::get_initialization_chunk(Metaspace::MetaspaceType type, Metaspace::MetadataType mdtype) { 4808 size_t chunk_word_size = get_space_manager(mdtype)->get_initial_chunk_size(type); 4809 4810 // Get a chunk from the chunk freelist 4811 Metachunk* chunk = Metaspace::get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size); 4812 4813 if (chunk == NULL) { 4814 chunk = Metaspace::get_space_list(mdtype)->get_new_chunk(chunk_word_size, 4815 get_space_manager(mdtype)->medium_chunk_bunch()); 4816 } 4817 4818 return chunk; 4819 } 4820 4821 void ClassLoaderMetaspace::initialize(Mutex* lock, Metaspace::MetaspaceType type) { 4822 Metaspace::verify_global_initialization(); 4823 4824 // Allocate SpaceManager for metadata objects. 4825 _vsm = new SpaceManager(Metaspace::NonClassType, type, lock); 4826 4827 if (Metaspace::using_class_space()) { 4828 // Allocate SpaceManager for classes. 4829 _class_vsm = new SpaceManager(Metaspace::ClassType, type, lock); 4830 } 4831 4832 MutexLockerEx cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag); 4833 4834 // Allocate chunk for metadata objects 4835 initialize_first_chunk(type, Metaspace::NonClassType); 4836 4837 // Allocate chunk for class metadata objects 4838 if (Metaspace::using_class_space()) { 4839 initialize_first_chunk(type, Metaspace::ClassType); 4840 } 4841 } 4842 4843 MetaWord* ClassLoaderMetaspace::allocate(size_t word_size, Metaspace::MetadataType mdtype) { 4844 Metaspace::assert_not_frozen(); 4845 // Don't use class_vsm() unless UseCompressedClassPointers is true. 4846 if (Metaspace::is_class_space_allocation(mdtype)) { 4847 return class_vsm()->allocate(word_size); 4848 } else { 4849 return vsm()->allocate(word_size); 4850 } 4851 } 4852 4853 MetaWord* ClassLoaderMetaspace::expand_and_allocate(size_t word_size, Metaspace::MetadataType mdtype) { 4854 Metaspace::assert_not_frozen(); 4855 size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord); 4856 assert(delta_bytes > 0, "Must be"); 4857 4858 size_t before = 0; 4859 size_t after = 0; 4860 MetaWord* res; 4861 bool incremented; 4862 4863 // Each thread increments the HWM at most once. Even if the thread fails to increment 4864 // the HWM, an allocation is still attempted. This is because another thread must then 4865 // have incremented the HWM and therefore the allocation might still succeed. 4866 do { 4867 incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before); 4868 res = allocate(word_size, mdtype); 4869 } while (!incremented && res == NULL); 4870 4871 if (incremented) { 4872 Metaspace::tracer()->report_gc_threshold(before, after, 4873 MetaspaceGCThresholdUpdater::ExpandAndAllocate); 4874 log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after); 4875 } 4876 4877 return res; 4878 } 4879 4880 size_t ClassLoaderMetaspace::used_words_slow(Metaspace::MetadataType mdtype) const { 4881 if (mdtype == Metaspace::ClassType) { 4882 return Metaspace::using_class_space() ? class_vsm()->sum_used_in_chunks_in_use() : 0; 4883 } else { 4884 return vsm()->sum_used_in_chunks_in_use(); // includes overhead! 4885 } 4886 } 4887 4888 size_t ClassLoaderMetaspace::free_words_slow(Metaspace::MetadataType mdtype) const { 4889 Metaspace::assert_not_frozen(); 4890 if (mdtype == Metaspace::ClassType) { 4891 return Metaspace::using_class_space() ? class_vsm()->sum_free_in_chunks_in_use() : 0; 4892 } else { 4893 return vsm()->sum_free_in_chunks_in_use(); 4894 } 4895 } 4896 4897 // Space capacity in the Metaspace. It includes 4898 // space in the list of chunks from which allocations 4899 // have been made. Don't include space in the global freelist and 4900 // in the space available in the dictionary which 4901 // is already counted in some chunk. 4902 size_t ClassLoaderMetaspace::capacity_words_slow(Metaspace::MetadataType mdtype) const { 4903 if (mdtype == Metaspace::ClassType) { 4904 return Metaspace::using_class_space() ? class_vsm()->sum_capacity_in_chunks_in_use() : 0; 4905 } else { 4906 return vsm()->sum_capacity_in_chunks_in_use(); 4907 } 4908 } 4909 4910 size_t ClassLoaderMetaspace::used_bytes_slow(Metaspace::MetadataType mdtype) const { 4911 return used_words_slow(mdtype) * BytesPerWord; 4912 } 4913 4914 size_t ClassLoaderMetaspace::capacity_bytes_slow(Metaspace::MetadataType mdtype) const { 4915 return capacity_words_slow(mdtype) * BytesPerWord; 4916 } 4917 4918 size_t ClassLoaderMetaspace::allocated_blocks_bytes() const { 4919 return vsm()->allocated_blocks_bytes() + 4920 (Metaspace::using_class_space() ? class_vsm()->allocated_blocks_bytes() : 0); 4921 } 4922 4923 size_t ClassLoaderMetaspace::allocated_chunks_bytes() const { 4924 return vsm()->allocated_chunks_bytes() + 4925 (Metaspace::using_class_space() ? class_vsm()->allocated_chunks_bytes() : 0); 4926 } 4927 4928 void ClassLoaderMetaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) { 4929 Metaspace::assert_not_frozen(); 4930 assert(!SafepointSynchronize::is_at_safepoint() 4931 || Thread::current()->is_VM_thread(), "should be the VM thread"); 4932 4933 MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag); 4934 4935 if (is_class && Metaspace::using_class_space()) { 4936 class_vsm()->deallocate(ptr, word_size); 4937 } else { 4938 vsm()->deallocate(ptr, word_size); 4939 } 4940 } 4941 4942 size_t ClassLoaderMetaspace::class_chunk_size(size_t word_size) { 4943 assert(Metaspace::using_class_space(), "Has to use class space"); 4944 return class_vsm()->calc_chunk_size(word_size); 4945 } 4946 4947 void ClassLoaderMetaspace::print_on(outputStream* out) const { 4948 // Print both class virtual space counts and metaspace. 4949 if (Verbose) { 4950 vsm()->print_on(out); 4951 if (Metaspace::using_class_space()) { 4952 class_vsm()->print_on(out); 4953 } 4954 } 4955 } 4956 4957 void ClassLoaderMetaspace::verify() { 4958 vsm()->verify(); 4959 if (Metaspace::using_class_space()) { 4960 class_vsm()->verify(); 4961 } 4962 } 4963 4964 void ClassLoaderMetaspace::dump(outputStream* const out) const { 4965 out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, p2i(vsm())); 4966 vsm()->dump(out); 4967 if (Metaspace::using_class_space()) { 4968 out->print_cr("\nClass space manager: " INTPTR_FORMAT, p2i(class_vsm())); 4969 class_vsm()->dump(out); 4970 } 4971 } 4972 4973 4974 4975 #ifdef ASSERT 4976 static void do_verify_chunk(Metachunk* chunk) { 4977 guarantee(chunk != NULL, "Sanity"); 4978 // Verify chunk itself; then verify that it is consistent with the 4979 // occupany map of its containing node. 4980 chunk->verify(); 4981 VirtualSpaceNode* const vsn = chunk->container(); 4982 OccupancyMap* const ocmap = vsn->occupancy_map(); 4983 ocmap->verify_for_chunk(chunk); 4984 } 4985 #endif 4986 4987 static void do_update_in_use_info_for_chunk(Metachunk* chunk, bool inuse) { 4988 chunk->set_is_tagged_free(!inuse); 4989 OccupancyMap* const ocmap = chunk->container()->occupancy_map(); 4990 ocmap->set_region_in_use((MetaWord*)chunk, chunk->word_size(), inuse); 4991 } 4992 4993 /////////////// Unit tests /////////////// 4994 4995 #ifndef PRODUCT 4996 4997 class TestMetaspaceUtilsTest : AllStatic { 4998 public: 4999 static void test_reserved() { 5000 size_t reserved = MetaspaceUtils::reserved_bytes(); 5001 5002 assert(reserved > 0, "assert"); 5003 5004 size_t committed = MetaspaceUtils::committed_bytes(); 5005 assert(committed <= reserved, "assert"); 5006 5007 size_t reserved_metadata = MetaspaceUtils::reserved_bytes(Metaspace::NonClassType); 5008 assert(reserved_metadata > 0, "assert"); 5009 assert(reserved_metadata <= reserved, "assert"); 5010 5011 if (UseCompressedClassPointers) { 5012 size_t reserved_class = MetaspaceUtils::reserved_bytes(Metaspace::ClassType); 5013 assert(reserved_class > 0, "assert"); 5014 assert(reserved_class < reserved, "assert"); 5015 } 5016 } 5017 5018 static void test_committed() { 5019 size_t committed = MetaspaceUtils::committed_bytes(); 5020 5021 assert(committed > 0, "assert"); 5022 5023 size_t reserved = MetaspaceUtils::reserved_bytes(); 5024 assert(committed <= reserved, "assert"); 5025 5026 size_t committed_metadata = MetaspaceUtils::committed_bytes(Metaspace::NonClassType); 5027 assert(committed_metadata > 0, "assert"); 5028 assert(committed_metadata <= committed, "assert"); 5029 5030 if (UseCompressedClassPointers) { 5031 size_t committed_class = MetaspaceUtils::committed_bytes(Metaspace::ClassType); 5032 assert(committed_class > 0, "assert"); 5033 assert(committed_class < committed, "assert"); 5034 } 5035 } 5036 5037 static void test_virtual_space_list_large_chunk() { 5038 VirtualSpaceList* vs_list = new VirtualSpaceList(os::vm_allocation_granularity()); 5039 MutexLockerEx cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag); 5040 // A size larger than VirtualSpaceSize (256k) and add one page to make it _not_ be 5041 // vm_allocation_granularity aligned on Windows. 5042 size_t large_size = (size_t)(2*256*K + (os::vm_page_size()/BytesPerWord)); 5043 large_size += (os::vm_page_size()/BytesPerWord); 5044 vs_list->get_new_chunk(large_size, 0); 5045 } 5046 5047 static void test() { 5048 test_reserved(); 5049 test_committed(); 5050 test_virtual_space_list_large_chunk(); 5051 } 5052 }; 5053 5054 void TestMetaspaceUtils_test() { 5055 TestMetaspaceUtilsTest::test(); 5056 } 5057 5058 class TestVirtualSpaceNodeTest { 5059 static void chunk_up(size_t words_left, size_t& num_medium_chunks, 5060 size_t& num_small_chunks, 5061 size_t& num_specialized_chunks) { 5062 num_medium_chunks = words_left / MediumChunk; 5063 words_left = words_left % MediumChunk; 5064 5065 num_small_chunks = words_left / SmallChunk; 5066 words_left = words_left % SmallChunk; 5067 // how many specialized chunks can we get? 5068 num_specialized_chunks = words_left / SpecializedChunk; 5069 assert(words_left % SpecializedChunk == 0, "should be nothing left"); 5070 } 5071 5072 public: 5073 static void test() { 5074 MutexLockerEx ml(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag); 5075 const size_t vsn_test_size_words = MediumChunk * 4; 5076 const size_t vsn_test_size_bytes = vsn_test_size_words * BytesPerWord; 5077 5078 // The chunk sizes must be multiples of eachother, or this will fail 5079 STATIC_ASSERT(MediumChunk % SmallChunk == 0); 5080 STATIC_ASSERT(SmallChunk % SpecializedChunk == 0); 5081 5082 { // No committed memory in VSN 5083 ChunkManager cm(false); 5084 VirtualSpaceNode vsn(false, vsn_test_size_bytes); 5085 vsn.initialize(); 5086 vsn.retire(&cm); 5087 assert(cm.sum_free_chunks_count() == 0, "did not commit any memory in the VSN"); 5088 } 5089 5090 { // All of VSN is committed, half is used by chunks 5091 ChunkManager cm(false); 5092 VirtualSpaceNode vsn(false, vsn_test_size_bytes); 5093 vsn.initialize(); 5094 vsn.expand_by(vsn_test_size_words, vsn_test_size_words); 5095 vsn.get_chunk_vs(MediumChunk); 5096 vsn.get_chunk_vs(MediumChunk); 5097 vsn.retire(&cm); 5098 assert(cm.sum_free_chunks_count() == 2, "should have been memory left for 2 medium chunks"); 5099 assert(cm.sum_free_chunks() == 2*MediumChunk, "sizes should add up"); 5100 } 5101 5102 const size_t page_chunks = 4 * (size_t)os::vm_page_size() / BytesPerWord; 5103 // This doesn't work for systems with vm_page_size >= 16K. 5104 if (page_chunks < MediumChunk) { 5105 // 4 pages of VSN is committed, some is used by chunks 5106 ChunkManager cm(false); 5107 VirtualSpaceNode vsn(false, vsn_test_size_bytes); 5108 5109 vsn.initialize(); 5110 vsn.expand_by(page_chunks, page_chunks); 5111 vsn.get_chunk_vs(SmallChunk); 5112 vsn.get_chunk_vs(SpecializedChunk); 5113 vsn.retire(&cm); 5114 5115 // committed - used = words left to retire 5116 const size_t words_left = page_chunks - SmallChunk - SpecializedChunk; 5117 5118 size_t num_medium_chunks, num_small_chunks, num_spec_chunks; 5119 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks); 5120 5121 assert(num_medium_chunks == 0, "should not get any medium chunks"); 5122 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks"); 5123 assert(cm.sum_free_chunks() == words_left, "sizes should add up"); 5124 } 5125 5126 { // Half of VSN is committed, a humongous chunk is used 5127 ChunkManager cm(false); 5128 VirtualSpaceNode vsn(false, vsn_test_size_bytes); 5129 vsn.initialize(); 5130 vsn.expand_by(MediumChunk * 2, MediumChunk * 2); 5131 vsn.get_chunk_vs(MediumChunk + SpecializedChunk); // Humongous chunks will be aligned up to MediumChunk + SpecializedChunk 5132 vsn.retire(&cm); 5133 5134 const size_t words_left = MediumChunk * 2 - (MediumChunk + SpecializedChunk); 5135 size_t num_medium_chunks, num_small_chunks, num_spec_chunks; 5136 chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks); 5137 5138 assert(num_medium_chunks == 0, "should not get any medium chunks"); 5139 assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks"); 5140 assert(cm.sum_free_chunks() == words_left, "sizes should add up"); 5141 } 5142 5143 } 5144 5145 #define assert_is_available_positive(word_size) \ 5146 assert(vsn.is_available(word_size), \ 5147 #word_size ": " PTR_FORMAT " bytes were not available in " \ 5148 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \ 5149 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())); 5150 5151 #define assert_is_available_negative(word_size) \ 5152 assert(!vsn.is_available(word_size), \ 5153 #word_size ": " PTR_FORMAT " bytes should not be available in " \ 5154 "VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \ 5155 (uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end())); 5156 5157 static void test_is_available_positive() { 5158 // Reserve some memory. 5159 VirtualSpaceNode vsn(false, os::vm_allocation_granularity()); 5160 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 5161 5162 // Commit some memory. 5163 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 5164 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 5165 assert(expanded, "Failed to commit"); 5166 5167 // Check that is_available accepts the committed size. 5168 assert_is_available_positive(commit_word_size); 5169 5170 // Check that is_available accepts half the committed size. 5171 size_t expand_word_size = commit_word_size / 2; 5172 assert_is_available_positive(expand_word_size); 5173 } 5174 5175 static void test_is_available_negative() { 5176 // Reserve some memory. 5177 VirtualSpaceNode vsn(false, os::vm_allocation_granularity()); 5178 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 5179 5180 // Commit some memory. 5181 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 5182 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 5183 assert(expanded, "Failed to commit"); 5184 5185 // Check that is_available doesn't accept a too large size. 5186 size_t two_times_commit_word_size = commit_word_size * 2; 5187 assert_is_available_negative(two_times_commit_word_size); 5188 } 5189 5190 static void test_is_available_overflow() { 5191 // Reserve some memory. 5192 VirtualSpaceNode vsn(false, os::vm_allocation_granularity()); 5193 assert(vsn.initialize(), "Failed to setup VirtualSpaceNode"); 5194 5195 // Commit some memory. 5196 size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord; 5197 bool expanded = vsn.expand_by(commit_word_size, commit_word_size); 5198 assert(expanded, "Failed to commit"); 5199 5200 // Calculate a size that will overflow the virtual space size. 5201 void* virtual_space_max = (void*)(uintptr_t)-1; 5202 size_t bottom_to_max = pointer_delta(virtual_space_max, vsn.bottom(), 1); 5203 size_t overflow_size = bottom_to_max + BytesPerWord; 5204 size_t overflow_word_size = overflow_size / BytesPerWord; 5205 5206 // Check that is_available can handle the overflow. 5207 assert_is_available_negative(overflow_word_size); 5208 } 5209 5210 static void test_is_available() { 5211 TestVirtualSpaceNodeTest::test_is_available_positive(); 5212 TestVirtualSpaceNodeTest::test_is_available_negative(); 5213 TestVirtualSpaceNodeTest::test_is_available_overflow(); 5214 } 5215 }; 5216 5217 // The following test is placed here instead of a gtest / unittest file 5218 // because the ChunkManager class is only available in this file. 5219 void ChunkManager_test_list_index() { 5220 { 5221 // Test previous bug where a query for a humongous class metachunk, 5222 // incorrectly matched the non-class medium metachunk size. 5223 { 5224 ChunkManager manager(true); 5225 5226 assert(MediumChunk > ClassMediumChunk, "Precondition for test"); 5227 5228 ChunkIndex index = manager.list_index(MediumChunk); 5229 5230 assert(index == HumongousIndex, 5231 "Requested size is larger than ClassMediumChunk," 5232 " so should return HumongousIndex. Got index: %d", (int)index); 5233 } 5234 5235 // Check the specified sizes as well. 5236 { 5237 ChunkManager manager(true); 5238 assert(manager.list_index(ClassSpecializedChunk) == SpecializedIndex, "sanity"); 5239 assert(manager.list_index(ClassSmallChunk) == SmallIndex, "sanity"); 5240 assert(manager.list_index(ClassMediumChunk) == MediumIndex, "sanity"); 5241 assert(manager.list_index(ClassMediumChunk + ClassSpecializedChunk) == HumongousIndex, "sanity"); 5242 } 5243 { 5244 ChunkManager manager(false); 5245 assert(manager.list_index(SpecializedChunk) == SpecializedIndex, "sanity"); 5246 assert(manager.list_index(SmallChunk) == SmallIndex, "sanity"); 5247 assert(manager.list_index(MediumChunk) == MediumIndex, "sanity"); 5248 assert(manager.list_index(MediumChunk + SpecializedChunk) == HumongousIndex, "sanity"); 5249 } 5250 5251 } 5252 5253 } 5254 5255 #endif // !PRODUCT 5256 5257 #ifdef ASSERT 5258 5259 // The following test is placed here instead of a gtest / unittest file 5260 // because the ChunkManager class is only available in this file. 5261 class SpaceManagerTest : AllStatic { 5262 friend void SpaceManager_test_adjust_initial_chunk_size(); 5263 5264 static void test_adjust_initial_chunk_size(bool is_class) { 5265 const size_t smallest = SpaceManager::smallest_chunk_size(is_class); 5266 const size_t normal = SpaceManager::small_chunk_size(is_class); 5267 const size_t medium = SpaceManager::medium_chunk_size(is_class); 5268 5269 #define test_adjust_initial_chunk_size(value, expected, is_class_value) \ 5270 do { \ 5271 size_t v = value; \ 5272 size_t e = expected; \ 5273 assert(SpaceManager::adjust_initial_chunk_size(v, (is_class_value)) == e, \ 5274 "Expected: " SIZE_FORMAT " got: " SIZE_FORMAT, e, v); \ 5275 } while (0) 5276 5277 // Smallest (specialized) 5278 test_adjust_initial_chunk_size(1, smallest, is_class); 5279 test_adjust_initial_chunk_size(smallest - 1, smallest, is_class); 5280 test_adjust_initial_chunk_size(smallest, smallest, is_class); 5281 5282 // Small 5283 test_adjust_initial_chunk_size(smallest + 1, normal, is_class); 5284 test_adjust_initial_chunk_size(normal - 1, normal, is_class); 5285 test_adjust_initial_chunk_size(normal, normal, is_class); 5286 5287 // Medium 5288 test_adjust_initial_chunk_size(normal + 1, medium, is_class); 5289 test_adjust_initial_chunk_size(medium - 1, medium, is_class); 5290 test_adjust_initial_chunk_size(medium, medium, is_class); 5291 5292 // Humongous 5293 test_adjust_initial_chunk_size(medium + 1, medium + 1, is_class); 5294 5295 #undef test_adjust_initial_chunk_size 5296 } 5297 5298 static void test_adjust_initial_chunk_size() { 5299 test_adjust_initial_chunk_size(false); 5300 test_adjust_initial_chunk_size(true); 5301 } 5302 }; 5303 5304 void SpaceManager_test_adjust_initial_chunk_size() { 5305 SpaceManagerTest::test_adjust_initial_chunk_size(); 5306 } 5307 5308 #endif // ASSERT 5309 5310 struct chunkmanager_statistics_t { 5311 int num_specialized_chunks; 5312 int num_small_chunks; 5313 int num_medium_chunks; 5314 int num_humongous_chunks; 5315 }; 5316 5317 extern void test_metaspace_retrieve_chunkmanager_statistics(Metaspace::MetadataType mdType, chunkmanager_statistics_t* out) { 5318 ChunkManager* const chunk_manager = Metaspace::get_chunk_manager(mdType); 5319 ChunkManager::ChunkManagerStatistics stat; 5320 chunk_manager->get_statistics(&stat); 5321 out->num_specialized_chunks = (int)stat.num_by_type[SpecializedIndex]; 5322 out->num_small_chunks = (int)stat.num_by_type[SmallIndex]; 5323 out->num_medium_chunks = (int)stat.num_by_type[MediumIndex]; 5324 out->num_humongous_chunks = (int)stat.num_humongous_chunks; 5325 } 5326 5327 struct chunk_geometry_t { 5328 size_t specialized_chunk_word_size; 5329 size_t small_chunk_word_size; 5330 size_t medium_chunk_word_size; 5331 }; 5332 5333 extern void test_metaspace_retrieve_chunk_geometry(Metaspace::MetadataType mdType, chunk_geometry_t* out) { 5334 if (mdType == Metaspace::NonClassType) { 5335 out->specialized_chunk_word_size = SpecializedChunk; 5336 out->small_chunk_word_size = SmallChunk; 5337 out->medium_chunk_word_size = MediumChunk; 5338 } else { 5339 out->specialized_chunk_word_size = ClassSpecializedChunk; 5340 out->small_chunk_word_size = ClassSmallChunk; 5341 out->medium_chunk_word_size = ClassMediumChunk; 5342 } 5343 }