/* * Copyright (c) 2011, 2013, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #include "precompiled.hpp" #include "gc_interface/collectedHeap.hpp" #include "memory/binaryTreeDictionary.hpp" #include "memory/freeList.hpp" #include "memory/collectorPolicy.hpp" #include "memory/filemap.hpp" #include "memory/freeList.hpp" #include "memory/metablock.hpp" #include "memory/metachunk.hpp" #include "memory/metaspace.hpp" #include "memory/metaspaceShared.hpp" #include "memory/resourceArea.hpp" #include "memory/universe.hpp" #include "runtime/globals.hpp" #include "runtime/java.hpp" #include "runtime/mutex.hpp" #include "runtime/orderAccess.hpp" #include "services/memTracker.hpp" #include "utilities/copy.hpp" #include "utilities/debug.hpp" typedef BinaryTreeDictionary BlockTreeDictionary; typedef BinaryTreeDictionary ChunkTreeDictionary; // Define this macro to enable slow integrity checking of // the free chunk lists const bool metaspace_slow_verify = false; // Parameters for stress mode testing const uint metadata_deallocate_a_lot_block = 10; const uint metadata_deallocate_a_lock_chunk = 3; size_t const allocation_from_dictionary_limit = 64 * K; MetaWord* last_allocated = 0; size_t Metaspace::_class_metaspace_size; // Used in declarations in SpaceManager and ChunkManager enum ChunkIndex { ZeroIndex = 0, SpecializedIndex = ZeroIndex, SmallIndex = SpecializedIndex + 1, MediumIndex = SmallIndex + 1, HumongousIndex = MediumIndex + 1, NumberOfFreeLists = 3, NumberOfInUseLists = 4 }; enum ChunkSizes { // in words. ClassSpecializedChunk = 128, SpecializedChunk = 128, ClassSmallChunk = 256, SmallChunk = 512, ClassMediumChunk = 4 * K, MediumChunk = 8 * K, HumongousChunkGranularity = 8 }; static ChunkIndex next_chunk_index(ChunkIndex i) { assert(i < NumberOfInUseLists, "Out of bound"); return (ChunkIndex) (i+1); } // Originally _capacity_until_GC was set to MetaspaceSize here but // the default MetaspaceSize before argument processing was being // used which was not the desired value. See the code // in should_expand() to see how the initialization is handled // now. size_t MetaspaceGC::_capacity_until_GC = 0; bool MetaspaceGC::_expand_after_GC = false; uint MetaspaceGC::_shrink_factor = 0; bool MetaspaceGC::_should_concurrent_collect = false; // Blocks of space for metadata are allocated out of Metachunks. // // Metachunk are allocated out of MetadataVirtualspaces and once // allocated there is no explicit link between a Metachunk and // the MetadataVirtualspaces from which it was allocated. // // Each SpaceManager maintains a // list of the chunks it is using and the current chunk. The current // chunk is the chunk from which allocations are done. Space freed in // a chunk is placed on the free list of blocks (BlockFreelist) and // reused from there. typedef class FreeList ChunkList; // Manages the global free lists of chunks. // Has three lists of free chunks, and a total size and // count that includes all three class ChunkManager VALUE_OBJ_CLASS_SPEC { // Free list of chunks of different sizes. // SpecializedChunk // SmallChunk // MediumChunk // HumongousChunk ChunkList _free_chunks[NumberOfFreeLists]; // HumongousChunk ChunkTreeDictionary _humongous_dictionary; // ChunkManager in all lists of this type size_t _free_chunks_total; size_t _free_chunks_count; void dec_free_chunks_total(size_t v) { assert(_free_chunks_count > 0 && _free_chunks_total > 0, "About to go negative"); Atomic::add_ptr(-1, &_free_chunks_count); jlong minus_v = (jlong) - (jlong) v; Atomic::add_ptr(minus_v, &_free_chunks_total); } // Debug support size_t sum_free_chunks(); size_t sum_free_chunks_count(); void locked_verify_free_chunks_total(); void slow_locked_verify_free_chunks_total() { if (metaspace_slow_verify) { locked_verify_free_chunks_total(); } } void locked_verify_free_chunks_count(); void slow_locked_verify_free_chunks_count() { if (metaspace_slow_verify) { locked_verify_free_chunks_count(); } } void verify_free_chunks_count(); public: ChunkManager() : _free_chunks_total(0), _free_chunks_count(0) {} // add or delete (return) a chunk to the global freelist. Metachunk* chunk_freelist_allocate(size_t word_size); void chunk_freelist_deallocate(Metachunk* chunk); // Map a size to a list index assuming that there are lists // for special, small, medium, and humongous chunks. static ChunkIndex list_index(size_t size); // Remove the chunk from its freelist. It is // expected to be on one of the _free_chunks[] lists. void remove_chunk(Metachunk* chunk); // Add the simple linked list of chunks to the freelist of chunks // of type index. void return_chunks(ChunkIndex index, Metachunk* chunks); // Total of the space in the free chunks list size_t free_chunks_total(); size_t free_chunks_total_in_bytes(); // Number of chunks in the free chunks list size_t free_chunks_count(); void inc_free_chunks_total(size_t v, size_t count = 1) { Atomic::add_ptr(count, &_free_chunks_count); Atomic::add_ptr(v, &_free_chunks_total); } ChunkTreeDictionary* humongous_dictionary() { return &_humongous_dictionary; } ChunkList* free_chunks(ChunkIndex index); // Returns the list for the given chunk word size. ChunkList* find_free_chunks_list(size_t word_size); // Add and remove from a list by size. Selects // list based on size of chunk. void free_chunks_put(Metachunk* chuck); Metachunk* free_chunks_get(size_t chunk_word_size); // Debug support void verify(); void slow_verify() { if (metaspace_slow_verify) { verify(); } } void locked_verify(); void slow_locked_verify() { if (metaspace_slow_verify) { locked_verify(); } } void verify_free_chunks_total(); void locked_print_free_chunks(outputStream* st); void locked_print_sum_free_chunks(outputStream* st); void print_on(outputStream* st); }; // Used to manage the free list of Metablocks (a block corresponds // to the allocation of a quantum of metadata). class BlockFreelist VALUE_OBJ_CLASS_SPEC { BlockTreeDictionary* _dictionary; static Metablock* initialize_free_chunk(MetaWord* p, size_t word_size); // Accessors BlockTreeDictionary* dictionary() const { return _dictionary; } public: BlockFreelist(); ~BlockFreelist(); // Get and return a block to the free list MetaWord* get_block(size_t word_size); void return_block(MetaWord* p, size_t word_size); size_t total_size() { if (dictionary() == NULL) { return 0; } else { return dictionary()->total_size(); } } void print_on(outputStream* st) const; }; class VirtualSpaceNode : public CHeapObj { friend class VirtualSpaceList; // Link to next VirtualSpaceNode VirtualSpaceNode* _next; // total in the VirtualSpace MemRegion _reserved; ReservedSpace _rs; VirtualSpace _virtual_space; MetaWord* _top; // count of chunks contained in this VirtualSpace uintx _container_count; // Convenience functions to access the _virtual_space char* low() const { return virtual_space()->low(); } char* high() const { return virtual_space()->high(); } // The first Metachunk will be allocated at the bottom of the // VirtualSpace Metachunk* first_chunk() { return (Metachunk*) bottom(); } void inc_container_count(); #ifdef ASSERT uint container_count_slow(); #endif public: VirtualSpaceNode(size_t byte_size); VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs), _container_count(0) {} ~VirtualSpaceNode(); // Convenience functions for logical bottom and end MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); } MetaWord* end() const { return (MetaWord*) _virtual_space.high(); } // address of next available space in _virtual_space; // Accessors VirtualSpaceNode* next() { return _next; } void set_next(VirtualSpaceNode* v) { _next = v; } void set_reserved(MemRegion const v) { _reserved = v; } void set_top(MetaWord* v) { _top = v; } // Accessors MemRegion* reserved() { return &_reserved; } VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; } // Returns true if "word_size" is available in the VirtualSpace bool is_available(size_t word_size) { return _top + word_size <= end(); } MetaWord* top() const { return _top; } void inc_top(size_t word_size) { _top += word_size; } uintx container_count() { return _container_count; } void dec_container_count(); #ifdef ASSERT void verify_container_count(); #endif // used and capacity in this single entry in the list size_t used_words_in_vs() const; size_t capacity_words_in_vs() const; size_t free_words_in_vs() const; bool initialize(); // get space from the virtual space Metachunk* take_from_committed(size_t chunk_word_size); // Allocate a chunk from the virtual space and return it. Metachunk* get_chunk_vs(size_t chunk_word_size); Metachunk* get_chunk_vs_with_expand(size_t chunk_word_size); // Expands/shrinks the committed space in a virtual space. Delegates // to Virtualspace bool expand_by(size_t words, bool pre_touch = false); bool shrink_by(size_t words); // In preparation for deleting this node, remove all the chunks // in the node from any freelist. void purge(ChunkManager* chunk_manager); #ifdef ASSERT // Debug support static void verify_virtual_space_total(); static void verify_virtual_space_count(); void mangle(); #endif void print_on(outputStream* st) const; }; // byte_size is the size of the associated virtualspace. VirtualSpaceNode::VirtualSpaceNode(size_t byte_size) : _top(NULL), _next(NULL), _rs(), _container_count(0) { // align up to vm allocation granularity byte_size = align_size_up(byte_size, os::vm_allocation_granularity()); // This allocates memory with mmap. For DumpSharedspaces, try to reserve // configurable address, generally at the top of the Java heap so other // memory addresses don't conflict. if (DumpSharedSpaces) { char* shared_base = (char*)SharedBaseAddress; _rs = ReservedSpace(byte_size, 0, false, shared_base, 0); if (_rs.is_reserved()) { assert(shared_base == 0 || _rs.base() == shared_base, "should match"); } else { // Get a mmap region anywhere if the SharedBaseAddress fails. _rs = ReservedSpace(byte_size); } MetaspaceShared::set_shared_rs(&_rs); } else { _rs = ReservedSpace(byte_size); } MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass); } void VirtualSpaceNode::purge(ChunkManager* chunk_manager) { Metachunk* chunk = first_chunk(); Metachunk* invalid_chunk = (Metachunk*) top(); while (chunk < invalid_chunk ) { assert(chunk->is_free(), "Should be marked free"); MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); chunk_manager->remove_chunk(chunk); assert(chunk->next() == NULL && chunk->prev() == NULL, "Was not removed from its list"); chunk = (Metachunk*) next; } } #ifdef ASSERT uint VirtualSpaceNode::container_count_slow() { uint count = 0; Metachunk* chunk = first_chunk(); Metachunk* invalid_chunk = (Metachunk*) top(); while (chunk < invalid_chunk ) { MetaWord* next = ((MetaWord*)chunk) + chunk->word_size(); // Don't count the chunks on the free lists. Those are // still part of the VirtualSpaceNode but not currently // counted. if (!chunk->is_free()) { count++; } chunk = (Metachunk*) next; } return count; } #endif // List of VirtualSpaces for metadata allocation. // It has a _next link for singly linked list and a MemRegion // for total space in the VirtualSpace. class VirtualSpaceList : public CHeapObj { friend class VirtualSpaceNode; enum VirtualSpaceSizes { VirtualSpaceSize = 256 * K }; // Global list of virtual spaces // Head of the list VirtualSpaceNode* _virtual_space_list; // virtual space currently being used for allocations VirtualSpaceNode* _current_virtual_space; // Free chunk list for all other metadata ChunkManager _chunk_manager; // Can this virtual list allocate >1 spaces? Also, used to determine // whether to allocate unlimited small chunks in this virtual space bool _is_class; bool can_grow() const { return !is_class() || !UseCompressedKlassPointers; } // Sum of space in all virtual spaces and number of virtual spaces size_t _virtual_space_total; size_t _virtual_space_count; ~VirtualSpaceList(); VirtualSpaceNode* virtual_space_list() const { return _virtual_space_list; } void set_virtual_space_list(VirtualSpaceNode* v) { _virtual_space_list = v; } void set_current_virtual_space(VirtualSpaceNode* v) { _current_virtual_space = v; } void link_vs(VirtualSpaceNode* new_entry, size_t vs_word_size); // Get another virtual space and add it to the list. This // is typically prompted by a failed attempt to allocate a chunk // and is typically followed by the allocation of a chunk. bool grow_vs(size_t vs_word_size); public: VirtualSpaceList(size_t word_size); VirtualSpaceList(ReservedSpace rs); size_t free_bytes(); Metachunk* get_new_chunk(size_t word_size, size_t grow_chunks_by_words, size_t medium_chunk_bunch); // Get the first chunk for a Metaspace. Used for // special cases such as the boot class loader, reflection // class loader and anonymous class loader. Metachunk* get_initialization_chunk(size_t word_size, size_t chunk_bunch); VirtualSpaceNode* current_virtual_space() { return _current_virtual_space; } ChunkManager* chunk_manager() { return &_chunk_manager; } bool is_class() const { return _is_class; } // Allocate the first virtualspace. void initialize(size_t word_size); size_t virtual_space_total() { return _virtual_space_total; } void inc_virtual_space_total(size_t v); void dec_virtual_space_total(size_t v); void inc_virtual_space_count(); void dec_virtual_space_count(); // Unlink empty VirtualSpaceNodes and free it. void purge(); // Used and capacity in the entire list of virtual spaces. // These are global values shared by all Metaspaces size_t capacity_words_sum(); size_t capacity_bytes_sum() { return capacity_words_sum() * BytesPerWord; } size_t used_words_sum(); size_t used_bytes_sum() { return used_words_sum() * BytesPerWord; } bool contains(const void *ptr); void print_on(outputStream* st) const; class VirtualSpaceListIterator : public StackObj { VirtualSpaceNode* _virtual_spaces; public: VirtualSpaceListIterator(VirtualSpaceNode* virtual_spaces) : _virtual_spaces(virtual_spaces) {} bool repeat() { return _virtual_spaces != NULL; } VirtualSpaceNode* get_next() { VirtualSpaceNode* result = _virtual_spaces; if (_virtual_spaces != NULL) { _virtual_spaces = _virtual_spaces->next(); } return result; } }; }; class Metadebug : AllStatic { // Debugging support for Metaspaces static int _deallocate_block_a_lot_count; static int _deallocate_chunk_a_lot_count; static int _allocation_fail_alot_count; public: static int deallocate_block_a_lot_count() { return _deallocate_block_a_lot_count; } static void set_deallocate_block_a_lot_count(int v) { _deallocate_block_a_lot_count = v; } static void inc_deallocate_block_a_lot_count() { _deallocate_block_a_lot_count++; } static int deallocate_chunk_a_lot_count() { return _deallocate_chunk_a_lot_count; } static void reset_deallocate_chunk_a_lot_count() { _deallocate_chunk_a_lot_count = 1; } static void inc_deallocate_chunk_a_lot_count() { _deallocate_chunk_a_lot_count++; } static void init_allocation_fail_alot_count(); #ifdef ASSERT static bool test_metadata_failure(); #endif static void deallocate_chunk_a_lot(SpaceManager* sm, size_t chunk_word_size); static void deallocate_block_a_lot(SpaceManager* sm, size_t chunk_word_size); }; int Metadebug::_deallocate_block_a_lot_count = 0; int Metadebug::_deallocate_chunk_a_lot_count = 0; int Metadebug::_allocation_fail_alot_count = 0; // SpaceManager - used by Metaspace to handle allocations class SpaceManager : public CHeapObj { friend class Metaspace; friend class Metadebug; private: // protects allocations and contains. Mutex* const _lock; // Type of metadata allocated. Metaspace::MetadataType _mdtype; // Chunk related size size_t _medium_chunk_bunch; // List of chunks in use by this SpaceManager. Allocations // are done from the current chunk. The list is used for deallocating // chunks when the SpaceManager is freed. Metachunk* _chunks_in_use[NumberOfInUseLists]; Metachunk* _current_chunk; // Virtual space where allocation comes from. VirtualSpaceList* _vs_list; // Number of small chunks to allocate to a manager // If class space manager, small chunks are unlimited static uint const _small_chunk_limit; // Sum of all space in allocated chunks size_t _allocated_blocks_words; // Sum of all allocated chunks size_t _allocated_chunks_words; size_t _allocated_chunks_count; // Free lists of blocks are per SpaceManager since they // are assumed to be in chunks in use by the SpaceManager // and all chunks in use by a SpaceManager are freed when // the class loader using the SpaceManager is collected. BlockFreelist _block_freelists; // protects virtualspace and chunk expansions static const char* _expand_lock_name; static const int _expand_lock_rank; static Mutex* const _expand_lock; private: // Accessors Metachunk* chunks_in_use(ChunkIndex index) const { return _chunks_in_use[index]; } void set_chunks_in_use(ChunkIndex index, Metachunk* v) { _chunks_in_use[index] = v; } BlockFreelist* block_freelists() const { return (BlockFreelist*) &_block_freelists; } Metaspace::MetadataType mdtype() { return _mdtype; } VirtualSpaceList* vs_list() const { return _vs_list; } Metachunk* current_chunk() const { return _current_chunk; } void set_current_chunk(Metachunk* v) { _current_chunk = v; } Metachunk* find_current_chunk(size_t word_size); // Add chunk to the list of chunks in use void add_chunk(Metachunk* v, bool make_current); Mutex* lock() const { return _lock; } const char* chunk_size_name(ChunkIndex index) const; protected: void initialize(); public: SpaceManager(Metaspace::MetadataType mdtype, Mutex* lock, VirtualSpaceList* vs_list); ~SpaceManager(); enum ChunkMultiples { MediumChunkMultiple = 4 }; // Accessors size_t specialized_chunk_size() { return SpecializedChunk; } size_t small_chunk_size() { return (size_t) vs_list()->is_class() ? ClassSmallChunk : SmallChunk; } size_t medium_chunk_size() { return (size_t) vs_list()->is_class() ? ClassMediumChunk : MediumChunk; } size_t medium_chunk_bunch() { return medium_chunk_size() * MediumChunkMultiple; } size_t allocated_blocks_words() const { return _allocated_blocks_words; } size_t allocated_blocks_bytes() const { return _allocated_blocks_words * BytesPerWord; } size_t allocated_chunks_words() const { return _allocated_chunks_words; } size_t allocated_chunks_count() const { return _allocated_chunks_count; } bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); } static Mutex* expand_lock() { return _expand_lock; } // Increment the per Metaspace and global running sums for Metachunks // by the given size. This is used when a Metachunk to added to // the in-use list. void inc_size_metrics(size_t words); // Increment the per Metaspace and global running sums Metablocks by the given // size. This is used when a Metablock is allocated. void inc_used_metrics(size_t words); // Delete the portion of the running sums for this SpaceManager. That is, // the globals running sums for the Metachunks and Metablocks are // decremented for all the Metachunks in-use by this SpaceManager. void dec_total_from_size_metrics(); // Set the sizes for the initial chunks. void get_initial_chunk_sizes(Metaspace::MetaspaceType type, size_t* chunk_word_size, size_t* class_chunk_word_size); size_t sum_capacity_in_chunks_in_use() const; size_t sum_used_in_chunks_in_use() const; size_t sum_free_in_chunks_in_use() const; size_t sum_waste_in_chunks_in_use() const; size_t sum_waste_in_chunks_in_use(ChunkIndex index ) const; size_t sum_count_in_chunks_in_use(); size_t sum_count_in_chunks_in_use(ChunkIndex i); Metachunk* get_new_chunk(size_t word_size, size_t grow_chunks_by_words); // Block allocation and deallocation. // Allocates a block from the current chunk MetaWord* allocate(size_t word_size); // Helper for allocations MetaWord* allocate_work(size_t word_size); // Returns a block to the per manager freelist void deallocate(MetaWord* p, size_t word_size); // Based on the allocation size and a minimum chunk size, // returned chunk size (for expanding space for chunk allocation). size_t calc_chunk_size(size_t allocation_word_size); // Called when an allocation from the current chunk fails. // Gets a new chunk (may require getting a new virtual space), // and allocates from that chunk. MetaWord* grow_and_allocate(size_t word_size); // debugging support. void dump(outputStream* const out) const; void print_on(outputStream* st) const; void locked_print_chunks_in_use_on(outputStream* st) const; void verify(); void verify_chunk_size(Metachunk* chunk); NOT_PRODUCT(void mangle_freed_chunks();) #ifdef ASSERT void verify_allocated_blocks_words(); #endif size_t get_raw_word_size(size_t word_size) { // If only the dictionary is going to be used (i.e., no // indexed free list), then there is a minimum size requirement. // MinChunkSize is a placeholder for the real minimum size JJJ size_t byte_size = word_size * BytesPerWord; size_t byte_size_with_overhead = byte_size + Metablock::overhead(); size_t raw_bytes_size = MAX2(byte_size_with_overhead, Metablock::min_block_byte_size()); raw_bytes_size = ARENA_ALIGN(raw_bytes_size); size_t raw_word_size = raw_bytes_size / BytesPerWord; assert(raw_word_size * BytesPerWord == raw_bytes_size, "Size problem"); return raw_word_size; } }; uint const SpaceManager::_small_chunk_limit = 4; const char* SpaceManager::_expand_lock_name = "SpaceManager chunk allocation lock"; const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1; Mutex* const SpaceManager::_expand_lock = new Mutex(SpaceManager::_expand_lock_rank, SpaceManager::_expand_lock_name, Mutex::_allow_vm_block_flag); void VirtualSpaceNode::inc_container_count() { assert_lock_strong(SpaceManager::expand_lock()); _container_count++; assert(_container_count == container_count_slow(), err_msg("Inconsistency in countainer_count _container_count " SIZE_FORMAT "container_count_slow() " SIZE_FORMAT, _container_count, container_count_slow())); } void VirtualSpaceNode::dec_container_count() { assert_lock_strong(SpaceManager::expand_lock()); _container_count--; } #ifdef ASSERT void VirtualSpaceNode::verify_container_count() { assert(_container_count == container_count_slow(), err_msg("Inconsistency in countainer_count _container_count " SIZE_FORMAT "container_count_slow() " SIZE_FORMAT, _container_count, container_count_slow())); } #endif // BlockFreelist methods BlockFreelist::BlockFreelist() : _dictionary(NULL) {} BlockFreelist::~BlockFreelist() { if (_dictionary != NULL) { if (Verbose && TraceMetadataChunkAllocation) { _dictionary->print_free_lists(gclog_or_tty); } delete _dictionary; } } Metablock* BlockFreelist::initialize_free_chunk(MetaWord* p, size_t word_size) { Metablock* block = (Metablock*) p; block->set_word_size(word_size); block->set_prev(NULL); block->set_next(NULL); return block; } void BlockFreelist::return_block(MetaWord* p, size_t word_size) { Metablock* free_chunk = initialize_free_chunk(p, word_size); if (dictionary() == NULL) { _dictionary = new BlockTreeDictionary(); } dictionary()->return_chunk(free_chunk); } MetaWord* BlockFreelist::get_block(size_t word_size) { if (dictionary() == NULL) { return NULL; } if (word_size < TreeChunk::min_size()) { // Dark matter. Too small for dictionary. return NULL; } Metablock* free_block = dictionary()->get_chunk(word_size, FreeBlockDictionary::exactly); if (free_block == NULL) { return NULL; } return (MetaWord*) free_block; } void BlockFreelist::print_on(outputStream* st) const { if (dictionary() == NULL) { return; } dictionary()->print_free_lists(st); } // VirtualSpaceNode methods VirtualSpaceNode::~VirtualSpaceNode() { _rs.release(); #ifdef ASSERT size_t word_size = sizeof(*this) / BytesPerWord; Copy::fill_to_words((HeapWord*) this, word_size, 0xf1f1f1f1); #endif } size_t VirtualSpaceNode::used_words_in_vs() const { return pointer_delta(top(), bottom(), sizeof(MetaWord)); } // Space committed in the VirtualSpace size_t VirtualSpaceNode::capacity_words_in_vs() const { return pointer_delta(end(), bottom(), sizeof(MetaWord)); } size_t VirtualSpaceNode::free_words_in_vs() const { return pointer_delta(end(), top(), sizeof(MetaWord)); } // Allocates the chunk from the virtual space only. // This interface is also used internally for debugging. Not all // chunks removed here are necessarily used for allocation. Metachunk* VirtualSpaceNode::take_from_committed(size_t chunk_word_size) { // Bottom of the new chunk MetaWord* chunk_limit = top(); assert(chunk_limit != NULL, "Not safe to call this method"); if (!is_available(chunk_word_size)) { if (TraceMetadataChunkAllocation) { tty->print("VirtualSpaceNode::take_from_committed() not available %d words ", chunk_word_size); // Dump some information about the virtual space that is nearly full print_on(tty); } return NULL; } // Take the space (bump top on the current virtual space). inc_top(chunk_word_size); // Initialize the chunk Metachunk* result = ::new (chunk_limit) Metachunk(chunk_word_size, this); return result; } // Expand the virtual space (commit more of the reserved space) bool VirtualSpaceNode::expand_by(size_t words, bool pre_touch) { size_t bytes = words * BytesPerWord; bool result = virtual_space()->expand_by(bytes, pre_touch); if (TraceMetavirtualspaceAllocation && !result) { gclog_or_tty->print_cr("VirtualSpaceNode::expand_by() failed " "for byte size " SIZE_FORMAT, bytes); virtual_space()->print(); } return result; } // Shrink the virtual space (commit more of the reserved space) bool VirtualSpaceNode::shrink_by(size_t words) { size_t bytes = words * BytesPerWord; virtual_space()->shrink_by(bytes); return true; } // Add another chunk to the chunk list. Metachunk* VirtualSpaceNode::get_chunk_vs(size_t chunk_word_size) { assert_lock_strong(SpaceManager::expand_lock()); Metachunk* result = take_from_committed(chunk_word_size); if (result != NULL) { inc_container_count(); } return result; } Metachunk* VirtualSpaceNode::get_chunk_vs_with_expand(size_t chunk_word_size) { assert_lock_strong(SpaceManager::expand_lock()); Metachunk* new_chunk = get_chunk_vs(chunk_word_size); if (new_chunk == NULL) { // Only a small part of the virtualspace is committed when first // allocated so committing more here can be expected. size_t page_size_words = os::vm_page_size() / BytesPerWord; size_t aligned_expand_vs_by_words = align_size_up(chunk_word_size, page_size_words); expand_by(aligned_expand_vs_by_words, false); new_chunk = get_chunk_vs(chunk_word_size); } return new_chunk; } bool VirtualSpaceNode::initialize() { if (!_rs.is_reserved()) { return false; } // An allocation out of this Virtualspace that is larger // than an initial commit size can waste that initial committed // space. size_t committed_byte_size = 0; bool result = virtual_space()->initialize(_rs, committed_byte_size); if (result) { set_top((MetaWord*)virtual_space()->low()); set_reserved(MemRegion((HeapWord*)_rs.base(), (HeapWord*)(_rs.base() + _rs.size()))); assert(reserved()->start() == (HeapWord*) _rs.base(), err_msg("Reserved start was not set properly " PTR_FORMAT " != " PTR_FORMAT, reserved()->start(), _rs.base())); assert(reserved()->word_size() == _rs.size() / BytesPerWord, err_msg("Reserved size was not set properly " SIZE_FORMAT " != " SIZE_FORMAT, reserved()->word_size(), _rs.size() / BytesPerWord)); } return result; } void VirtualSpaceNode::print_on(outputStream* st) const { size_t used = used_words_in_vs(); size_t capacity = capacity_words_in_vs(); VirtualSpace* vs = virtual_space(); st->print_cr(" space @ " PTR_FORMAT " " SIZE_FORMAT "K, %3d%% used " "[" PTR_FORMAT ", " PTR_FORMAT ", " PTR_FORMAT ", " PTR_FORMAT ")", vs, capacity / K, capacity == 0 ? 0 : used * 100 / capacity, bottom(), top(), end(), vs->high_boundary()); } #ifdef ASSERT void VirtualSpaceNode::mangle() { size_t word_size = capacity_words_in_vs(); Copy::fill_to_words((HeapWord*) low(), word_size, 0xf1f1f1f1); } #endif // ASSERT // VirtualSpaceList methods // Space allocated from the VirtualSpace VirtualSpaceList::~VirtualSpaceList() { VirtualSpaceListIterator iter(virtual_space_list()); while (iter.repeat()) { VirtualSpaceNode* vsl = iter.get_next(); delete vsl; } } void VirtualSpaceList::inc_virtual_space_total(size_t v) { assert_lock_strong(SpaceManager::expand_lock()); _virtual_space_total = _virtual_space_total + v; } void VirtualSpaceList::dec_virtual_space_total(size_t v) { assert_lock_strong(SpaceManager::expand_lock()); _virtual_space_total = _virtual_space_total - v; } void VirtualSpaceList::inc_virtual_space_count() { assert_lock_strong(SpaceManager::expand_lock()); _virtual_space_count++; } void VirtualSpaceList::dec_virtual_space_count() { assert_lock_strong(SpaceManager::expand_lock()); _virtual_space_count--; } void ChunkManager::remove_chunk(Metachunk* chunk) { size_t word_size = chunk->word_size(); ChunkIndex index = list_index(word_size); if (index != HumongousIndex) { free_chunks(index)->remove_chunk(chunk); } else { humongous_dictionary()->remove_chunk(chunk); } // Chunk is being removed from the chunks free list. dec_free_chunks_total(chunk->capacity_word_size()); } // Walk the list of VirtualSpaceNodes and delete // nodes with a 0 container_count. Remove Metachunks in // the node from their respective freelists. void VirtualSpaceList::purge() { assert_lock_strong(SpaceManager::expand_lock()); // Don't use a VirtualSpaceListIterator because this // list is being changed and a straightforward use of an iterator is not safe. VirtualSpaceNode* purged_vsl = NULL; VirtualSpaceNode* prev_vsl = virtual_space_list(); VirtualSpaceNode* next_vsl = prev_vsl; while (next_vsl != NULL) { VirtualSpaceNode* vsl = next_vsl; next_vsl = vsl->next(); // Don't free the current virtual space since it will likely // be needed soon. if (vsl->container_count() == 0 && vsl != current_virtual_space()) { // Unlink it from the list if (prev_vsl == vsl) { // This is the case of the current note being the first note. assert(vsl == virtual_space_list(), "Expected to be the first note"); set_virtual_space_list(vsl->next()); } else { prev_vsl->set_next(vsl->next()); } vsl->purge(chunk_manager()); dec_virtual_space_total(vsl->reserved()->word_size()); dec_virtual_space_count(); purged_vsl = vsl; delete vsl; } else { prev_vsl = vsl; } } #ifdef ASSERT if (purged_vsl != NULL) { // List should be stable enough to use an iterator here. VirtualSpaceListIterator iter(virtual_space_list()); while (iter.repeat()) { VirtualSpaceNode* vsl = iter.get_next(); assert(vsl != purged_vsl, "Purge of vsl failed"); } } #endif } size_t VirtualSpaceList::used_words_sum() { size_t allocated_by_vs = 0; VirtualSpaceListIterator iter(virtual_space_list()); while (iter.repeat()) { VirtualSpaceNode* vsl = iter.get_next(); // Sum used region [bottom, top) in each virtualspace allocated_by_vs += vsl->used_words_in_vs(); } assert(allocated_by_vs >= chunk_manager()->free_chunks_total(), err_msg("Total in free chunks " SIZE_FORMAT " greater than total from virtual_spaces " SIZE_FORMAT, allocated_by_vs, chunk_manager()->free_chunks_total())); size_t used = allocated_by_vs - chunk_manager()->free_chunks_total(); return used; } // Space available in all MetadataVirtualspaces allocated // for metadata. This is the upper limit on the capacity // of chunks allocated out of all the MetadataVirtualspaces. size_t VirtualSpaceList::capacity_words_sum() { size_t capacity = 0; VirtualSpaceListIterator iter(virtual_space_list()); while (iter.repeat()) { VirtualSpaceNode* vsl = iter.get_next(); capacity += vsl->capacity_words_in_vs(); } return capacity; } VirtualSpaceList::VirtualSpaceList(size_t word_size ) : _is_class(false), _virtual_space_list(NULL), _current_virtual_space(NULL), _virtual_space_total(0), _virtual_space_count(0) { MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); bool initialization_succeeded = grow_vs(word_size); _chunk_manager.free_chunks(SpecializedIndex)->set_size(SpecializedChunk); _chunk_manager.free_chunks(SmallIndex)->set_size(SmallChunk); _chunk_manager.free_chunks(MediumIndex)->set_size(MediumChunk); assert(initialization_succeeded, " VirtualSpaceList initialization should not fail"); } VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) : _is_class(true), _virtual_space_list(NULL), _current_virtual_space(NULL), _virtual_space_total(0), _virtual_space_count(0) { MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); VirtualSpaceNode* class_entry = new VirtualSpaceNode(rs); bool succeeded = class_entry->initialize(); _chunk_manager.free_chunks(SpecializedIndex)->set_size(SpecializedChunk); _chunk_manager.free_chunks(SmallIndex)->set_size(ClassSmallChunk); _chunk_manager.free_chunks(MediumIndex)->set_size(ClassMediumChunk); assert(succeeded, " VirtualSpaceList initialization should not fail"); link_vs(class_entry, rs.size()/BytesPerWord); } size_t VirtualSpaceList::free_bytes() { return virtual_space_list()->free_words_in_vs() * BytesPerWord; } // Allocate another meta virtual space and add it to the list. bool VirtualSpaceList::grow_vs(size_t vs_word_size) { assert_lock_strong(SpaceManager::expand_lock()); if (vs_word_size == 0) { return false; } // Reserve the space size_t vs_byte_size = vs_word_size * BytesPerWord; assert(vs_byte_size % os::vm_page_size() == 0, "Not aligned"); // Allocate the meta virtual space and initialize it. VirtualSpaceNode* new_entry = new VirtualSpaceNode(vs_byte_size); if (!new_entry->initialize()) { delete new_entry; return false; } else { // ensure lock-free iteration sees fully initialized node OrderAccess::storestore(); link_vs(new_entry, vs_word_size); return true; } } void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry, size_t vs_word_size) { if (virtual_space_list() == NULL) { set_virtual_space_list(new_entry); } else { current_virtual_space()->set_next(new_entry); } set_current_virtual_space(new_entry); inc_virtual_space_total(vs_word_size); inc_virtual_space_count(); #ifdef ASSERT new_entry->mangle(); #endif if (TraceMetavirtualspaceAllocation && Verbose) { VirtualSpaceNode* vsl = current_virtual_space(); vsl->print_on(tty); } } Metachunk* VirtualSpaceList::get_new_chunk(size_t word_size, size_t grow_chunks_by_words, size_t medium_chunk_bunch) { // Get a chunk from the chunk freelist Metachunk* next = chunk_manager()->chunk_freelist_allocate(grow_chunks_by_words); if (next != NULL) { next->container()->inc_container_count(); } else { // Allocate a chunk out of the current virtual space. next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words); } if (next == NULL) { // Not enough room in current virtual space. Try to commit // more space. size_t expand_vs_by_words = MAX2(medium_chunk_bunch, grow_chunks_by_words); size_t page_size_words = os::vm_page_size() / BytesPerWord; size_t aligned_expand_vs_by_words = align_size_up(expand_vs_by_words, page_size_words); bool vs_expanded = current_virtual_space()->expand_by(aligned_expand_vs_by_words, false); if (!vs_expanded) { // Should the capacity of the metaspaces be expanded for // this allocation? If it's the virtual space for classes and is // being used for CompressedHeaders, don't allocate a new virtualspace. if (can_grow() && MetaspaceGC::should_expand(this, word_size)) { // Get another virtual space. size_t grow_vs_words = MAX2((size_t)VirtualSpaceSize, aligned_expand_vs_by_words); if (grow_vs(grow_vs_words)) { // Got it. It's on the list now. Get a chunk from it. next = current_virtual_space()->get_chunk_vs_with_expand(grow_chunks_by_words); } } else { // Allocation will fail and induce a GC if (TraceMetadataChunkAllocation && Verbose) { gclog_or_tty->print_cr("VirtualSpaceList::get_new_chunk():" " Fail instead of expand the metaspace"); } } } else { // The virtual space expanded, get a new chunk next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words); assert(next != NULL, "Just expanded, should succeed"); } } assert(next == NULL || (next->next() == NULL && next->prev() == NULL), "New chunk is still on some list"); return next; } Metachunk* VirtualSpaceList::get_initialization_chunk(size_t chunk_word_size, size_t chunk_bunch) { // Get a chunk from the chunk freelist Metachunk* new_chunk = get_new_chunk(chunk_word_size, chunk_word_size, chunk_bunch); return new_chunk; } void VirtualSpaceList::print_on(outputStream* st) const { if (TraceMetadataChunkAllocation && Verbose) { VirtualSpaceListIterator iter(virtual_space_list()); while (iter.repeat()) { VirtualSpaceNode* node = iter.get_next(); node->print_on(st); } } } bool VirtualSpaceList::contains(const void *ptr) { VirtualSpaceNode* list = virtual_space_list(); VirtualSpaceListIterator iter(list); while (iter.repeat()) { VirtualSpaceNode* node = iter.get_next(); if (node->reserved()->contains(ptr)) { return true; } } return false; } // MetaspaceGC methods // VM_CollectForMetadataAllocation is the vm operation used to GC. // Within the VM operation after the GC the attempt to allocate the metadata // should succeed. If the GC did not free enough space for the metaspace // allocation, the HWM is increased so that another virtualspace will be // allocated for the metadata. With perm gen the increase in the perm // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The // metaspace policy uses those as the small and large steps for the HWM. // // After the GC the compute_new_size() for MetaspaceGC is called to // resize the capacity of the metaspaces. The current implementation // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used // to resize the Java heap by some GC's. New flags can be implemented // if really needed. MinMetaspaceFreeRatio is used to calculate how much // free space is desirable in the metaspace capacity to decide how much // to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much // free space is desirable in the metaspace capacity before decreasing // the HWM. // Calculate the amount to increase the high water mark (HWM). // Increase by a minimum amount (MinMetaspaceExpansion) so that // another expansion is not requested too soon. If that is not // enough to satisfy the allocation (i.e. big enough for a word_size // allocation), increase by MaxMetaspaceExpansion. If that is still // not enough, expand by the size of the allocation (word_size) plus // some. size_t MetaspaceGC::delta_capacity_until_GC(size_t word_size) { size_t before_inc = MetaspaceGC::capacity_until_GC(); size_t min_delta_words = MinMetaspaceExpansion / BytesPerWord; size_t max_delta_words = MaxMetaspaceExpansion / BytesPerWord; size_t page_size_words = os::vm_page_size() / BytesPerWord; size_t size_delta_words = align_size_up(word_size, page_size_words); size_t delta_words = MAX2(size_delta_words, min_delta_words); if (delta_words > min_delta_words) { // Don't want to hit the high water mark on the next // allocation so make the delta greater than just enough // for this allocation. delta_words = MAX2(delta_words, max_delta_words); if (delta_words > max_delta_words) { // This allocation is large but the next ones are probably not // so increase by the minimum. delta_words = delta_words + min_delta_words; } } return delta_words; } bool MetaspaceGC::should_expand(VirtualSpaceList* vsl, size_t word_size) { // If the user wants a limit, impose one. // The reason for someone using this flag is to limit reserved space. So // for non-class virtual space, compare against virtual spaces that are reserved. // For class virtual space, we only compare against the committed space, not // reserved space, because this is a larger space prereserved for compressed // class pointers. if (!FLAG_IS_DEFAULT(MaxMetaspaceSize)) { size_t real_allocated = Metaspace::space_list()->virtual_space_total() + MetaspaceAux::allocated_capacity_bytes(Metaspace::ClassType); if (real_allocated >= MaxMetaspaceSize) { return false; } } // Class virtual space should always be expanded. Call GC for the other // metadata virtual space. if (Metaspace::using_class_space() && (vsl == Metaspace::class_space_list())) return true; // If this is part of an allocation after a GC, expand // unconditionally. if (MetaspaceGC::expand_after_GC()) { return true; } // If the capacity is below the minimum capacity, allow the // expansion. Also set the high-water-mark (capacity_until_GC) // to that minimum capacity so that a GC will not be induced // until that minimum capacity is exceeded. size_t committed_capacity_bytes = MetaspaceAux::allocated_capacity_bytes(); size_t metaspace_size_bytes = MetaspaceSize; if (committed_capacity_bytes < metaspace_size_bytes || capacity_until_GC() == 0) { set_capacity_until_GC(metaspace_size_bytes); return true; } else { if (committed_capacity_bytes < capacity_until_GC()) { return true; } else { if (TraceMetadataChunkAllocation && Verbose) { gclog_or_tty->print_cr(" allocation request size " SIZE_FORMAT " capacity_until_GC " SIZE_FORMAT " allocated_capacity_bytes " SIZE_FORMAT, word_size, capacity_until_GC(), MetaspaceAux::allocated_capacity_bytes()); } return false; } } } void MetaspaceGC::compute_new_size() { assert(_shrink_factor <= 100, "invalid shrink factor"); uint current_shrink_factor = _shrink_factor; _shrink_factor = 0; // Until a faster way of calculating the "used" quantity is implemented, // use "capacity". const size_t used_after_gc = MetaspaceAux::allocated_capacity_bytes(); const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC(); const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0; const double maximum_used_percentage = 1.0 - minimum_free_percentage; const double min_tmp = used_after_gc / maximum_used_percentage; size_t minimum_desired_capacity = (size_t)MIN2(min_tmp, double(max_uintx)); // Don't shrink less than the initial generation size minimum_desired_capacity = MAX2(minimum_desired_capacity, MetaspaceSize); if (PrintGCDetails && Verbose) { gclog_or_tty->print_cr("\nMetaspaceGC::compute_new_size: "); gclog_or_tty->print_cr(" " " minimum_free_percentage: %6.2f" " maximum_used_percentage: %6.2f", minimum_free_percentage, maximum_used_percentage); gclog_or_tty->print_cr(" " " used_after_gc : %6.1fKB", used_after_gc / (double) K); } size_t shrink_bytes = 0; if (capacity_until_GC < minimum_desired_capacity) { // If we have less capacity below the metaspace HWM, then // increment the HWM. size_t expand_bytes = minimum_desired_capacity - capacity_until_GC; // Don't expand unless it's significant if (expand_bytes >= MinMetaspaceExpansion) { MetaspaceGC::set_capacity_until_GC(capacity_until_GC + expand_bytes); } if (PrintGCDetails && Verbose) { size_t new_capacity_until_GC = capacity_until_GC; gclog_or_tty->print_cr(" expanding:" " minimum_desired_capacity: %6.1fKB" " expand_bytes: %6.1fKB" " MinMetaspaceExpansion: %6.1fKB" " new metaspace HWM: %6.1fKB", minimum_desired_capacity / (double) K, expand_bytes / (double) K, MinMetaspaceExpansion / (double) K, new_capacity_until_GC / (double) K); } return; } // No expansion, now see if we want to shrink // We would never want to shrink more than this size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity; assert(max_shrink_bytes >= 0, err_msg("max_shrink_bytes " SIZE_FORMAT, max_shrink_bytes)); // Should shrinking be considered? if (MaxMetaspaceFreeRatio < 100) { const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0; const double minimum_used_percentage = 1.0 - maximum_free_percentage; const double max_tmp = used_after_gc / minimum_used_percentage; size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx)); maximum_desired_capacity = MAX2(maximum_desired_capacity, MetaspaceSize); if (PrintGCDetails && Verbose) { gclog_or_tty->print_cr(" " " maximum_free_percentage: %6.2f" " minimum_used_percentage: %6.2f", maximum_free_percentage, minimum_used_percentage); gclog_or_tty->print_cr(" " " minimum_desired_capacity: %6.1fKB" " maximum_desired_capacity: %6.1fKB", minimum_desired_capacity / (double) K, maximum_desired_capacity / (double) K); } assert(minimum_desired_capacity <= maximum_desired_capacity, "sanity check"); if (capacity_until_GC > maximum_desired_capacity) { // Capacity too large, compute shrinking size shrink_bytes = capacity_until_GC - maximum_desired_capacity; // We don't want shrink all the way back to initSize if people call // System.gc(), because some programs do that between "phases" and then // we'd just have to grow the heap up again for the next phase. So we // damp the shrinking: 0% on the first call, 10% on the second call, 40% // on the third call, and 100% by the fourth call. But if we recompute // size without shrinking, it goes back to 0%. shrink_bytes = shrink_bytes / 100 * current_shrink_factor; assert(shrink_bytes <= max_shrink_bytes, err_msg("invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT, shrink_bytes, max_shrink_bytes)); if (current_shrink_factor == 0) { _shrink_factor = 10; } else { _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100); } if (PrintGCDetails && Verbose) { gclog_or_tty->print_cr(" " " shrinking:" " initSize: %.1fK" " maximum_desired_capacity: %.1fK", MetaspaceSize / (double) K, maximum_desired_capacity / (double) K); gclog_or_tty->print_cr(" " " shrink_bytes: %.1fK" " current_shrink_factor: %d" " new shrink factor: %d" " MinMetaspaceExpansion: %.1fK", shrink_bytes / (double) K, current_shrink_factor, _shrink_factor, MinMetaspaceExpansion / (double) K); } } } // Don't shrink unless it's significant if (shrink_bytes >= MinMetaspaceExpansion && ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) { MetaspaceGC::set_capacity_until_GC(capacity_until_GC - shrink_bytes); } } // Metadebug methods void Metadebug::deallocate_chunk_a_lot(SpaceManager* sm, size_t chunk_word_size){ #ifdef ASSERT VirtualSpaceList* vsl = sm->vs_list(); if (MetaDataDeallocateALot && Metadebug::deallocate_chunk_a_lot_count() % MetaDataDeallocateALotInterval == 0 ) { Metadebug::reset_deallocate_chunk_a_lot_count(); for (uint i = 0; i < metadata_deallocate_a_lock_chunk; i++) { Metachunk* dummy_chunk = vsl->current_virtual_space()->take_from_committed(chunk_word_size); if (dummy_chunk == NULL) { break; } vsl->chunk_manager()->chunk_freelist_deallocate(dummy_chunk); if (TraceMetadataChunkAllocation && Verbose) { gclog_or_tty->print("Metadebug::deallocate_chunk_a_lot: %d) ", sm->sum_count_in_chunks_in_use()); dummy_chunk->print_on(gclog_or_tty); gclog_or_tty->print_cr(" Free chunks total %d count %d", vsl->chunk_manager()->free_chunks_total(), vsl->chunk_manager()->free_chunks_count()); } } } else { Metadebug::inc_deallocate_chunk_a_lot_count(); } #endif } void Metadebug::deallocate_block_a_lot(SpaceManager* sm, size_t raw_word_size){ #ifdef ASSERT if (MetaDataDeallocateALot && Metadebug::deallocate_block_a_lot_count() % MetaDataDeallocateALotInterval == 0 ) { Metadebug::set_deallocate_block_a_lot_count(0); for (uint i = 0; i < metadata_deallocate_a_lot_block; i++) { MetaWord* dummy_block = sm->allocate_work(raw_word_size); if (dummy_block == 0) { break; } sm->deallocate(dummy_block, raw_word_size); } } else { Metadebug::inc_deallocate_block_a_lot_count(); } #endif } void Metadebug::init_allocation_fail_alot_count() { if (MetadataAllocationFailALot) { _allocation_fail_alot_count = 1+(long)((double)MetadataAllocationFailALotInterval*os::random()/(max_jint+1.0)); } } #ifdef ASSERT bool Metadebug::test_metadata_failure() { if (MetadataAllocationFailALot && Threads::is_vm_complete()) { if (_allocation_fail_alot_count > 0) { _allocation_fail_alot_count--; } else { if (TraceMetadataChunkAllocation && Verbose) { gclog_or_tty->print_cr("Metadata allocation failing for " "MetadataAllocationFailALot"); } init_allocation_fail_alot_count(); return true; } } return false; } #endif // ChunkManager methods size_t ChunkManager::free_chunks_total() { return _free_chunks_total; } size_t ChunkManager::free_chunks_total_in_bytes() { return free_chunks_total() * BytesPerWord; } size_t ChunkManager::free_chunks_count() { #ifdef ASSERT if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) { MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); // This lock is only needed in debug because the verification // of the _free_chunks_totals walks the list of free chunks slow_locked_verify_free_chunks_count(); } #endif return _free_chunks_count; } void ChunkManager::locked_verify_free_chunks_total() { assert_lock_strong(SpaceManager::expand_lock()); assert(sum_free_chunks() == _free_chunks_total, err_msg("_free_chunks_total " SIZE_FORMAT " is not the" " same as sum " SIZE_FORMAT, _free_chunks_total, sum_free_chunks())); } void ChunkManager::verify_free_chunks_total() { MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); locked_verify_free_chunks_total(); } void ChunkManager::locked_verify_free_chunks_count() { assert_lock_strong(SpaceManager::expand_lock()); assert(sum_free_chunks_count() == _free_chunks_count, err_msg("_free_chunks_count " SIZE_FORMAT " is not the" " same as sum " SIZE_FORMAT, _free_chunks_count, sum_free_chunks_count())); } void ChunkManager::verify_free_chunks_count() { #ifdef ASSERT MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); locked_verify_free_chunks_count(); #endif } void ChunkManager::verify() { MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); locked_verify(); } void ChunkManager::locked_verify() { locked_verify_free_chunks_count(); locked_verify_free_chunks_total(); } void ChunkManager::locked_print_free_chunks(outputStream* st) { assert_lock_strong(SpaceManager::expand_lock()); st->print_cr("Free chunk total " SIZE_FORMAT " count " SIZE_FORMAT, _free_chunks_total, _free_chunks_count); } void ChunkManager::locked_print_sum_free_chunks(outputStream* st) { assert_lock_strong(SpaceManager::expand_lock()); st->print_cr("Sum free chunk total " SIZE_FORMAT " count " SIZE_FORMAT, sum_free_chunks(), sum_free_chunks_count()); } ChunkList* ChunkManager::free_chunks(ChunkIndex index) { return &_free_chunks[index]; } // These methods that sum the free chunk lists are used in printing // methods that are used in product builds. size_t ChunkManager::sum_free_chunks() { assert_lock_strong(SpaceManager::expand_lock()); size_t result = 0; for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { ChunkList* list = free_chunks(i); if (list == NULL) { continue; } result = result + list->count() * list->size(); } result = result + humongous_dictionary()->total_size(); return result; } size_t ChunkManager::sum_free_chunks_count() { assert_lock_strong(SpaceManager::expand_lock()); size_t count = 0; for (ChunkIndex i = ZeroIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { ChunkList* list = free_chunks(i); if (list == NULL) { continue; } count = count + list->count(); } count = count + humongous_dictionary()->total_free_blocks(); return count; } ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) { ChunkIndex index = list_index(word_size); assert(index < HumongousIndex, "No humongous list"); return free_chunks(index); } void ChunkManager::free_chunks_put(Metachunk* chunk) { assert_lock_strong(SpaceManager::expand_lock()); ChunkList* free_list = find_free_chunks_list(chunk->word_size()); chunk->set_next(free_list->head()); free_list->set_head(chunk); // chunk is being returned to the chunk free list inc_free_chunks_total(chunk->capacity_word_size()); slow_locked_verify(); } void ChunkManager::chunk_freelist_deallocate(Metachunk* chunk) { // The deallocation of a chunk originates in the freelist // manangement code for a Metaspace and does not hold the // lock. assert(chunk != NULL, "Deallocating NULL"); assert_lock_strong(SpaceManager::expand_lock()); slow_locked_verify(); if (TraceMetadataChunkAllocation) { tty->print_cr("ChunkManager::chunk_freelist_deallocate: chunk " PTR_FORMAT " size " SIZE_FORMAT, chunk, chunk->word_size()); } free_chunks_put(chunk); } Metachunk* ChunkManager::free_chunks_get(size_t word_size) { assert_lock_strong(SpaceManager::expand_lock()); slow_locked_verify(); Metachunk* chunk = NULL; if (list_index(word_size) != HumongousIndex) { ChunkList* free_list = find_free_chunks_list(word_size); assert(free_list != NULL, "Sanity check"); chunk = free_list->head(); debug_only(Metachunk* debug_head = chunk;) if (chunk == NULL) { return NULL; } // Remove the chunk as the head of the list. free_list->remove_chunk(chunk); // Chunk is being removed from the chunks free list. dec_free_chunks_total(chunk->capacity_word_size()); if (TraceMetadataChunkAllocation && Verbose) { tty->print_cr("ChunkManager::free_chunks_get: free_list " PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT, free_list, chunk, chunk->word_size()); } } else { chunk = humongous_dictionary()->get_chunk( word_size, FreeBlockDictionary::atLeast); if (chunk != NULL) { if (TraceMetadataHumongousAllocation) { size_t waste = chunk->word_size() - word_size; tty->print_cr("Free list allocate humongous chunk size " SIZE_FORMAT " for requested size " SIZE_FORMAT " waste " SIZE_FORMAT, chunk->word_size(), word_size, waste); } // Chunk is being removed from the chunks free list. dec_free_chunks_total(chunk->capacity_word_size()); } else { return NULL; } } // Remove it from the links to this freelist chunk->set_next(NULL); chunk->set_prev(NULL); #ifdef ASSERT // Chunk is no longer on any freelist. Setting to false make container_count_slow() // work. chunk->set_is_free(false); #endif slow_locked_verify(); return chunk; } Metachunk* ChunkManager::chunk_freelist_allocate(size_t word_size) { assert_lock_strong(SpaceManager::expand_lock()); slow_locked_verify(); // Take from the beginning of the list Metachunk* chunk = free_chunks_get(word_size); if (chunk == NULL) { return NULL; } assert((word_size <= chunk->word_size()) || list_index(chunk->word_size() == HumongousIndex), "Non-humongous variable sized chunk"); if (TraceMetadataChunkAllocation) { size_t list_count; if (list_index(word_size) < HumongousIndex) { ChunkList* list = find_free_chunks_list(word_size); list_count = list->count(); } else { list_count = humongous_dictionary()->total_count(); } tty->print("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk " PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ", this, chunk, chunk->word_size(), list_count); locked_print_free_chunks(tty); } return chunk; } void ChunkManager::print_on(outputStream* out) { if (PrintFLSStatistics != 0) { humongous_dictionary()->report_statistics(); } } // SpaceManager methods void SpaceManager::get_initial_chunk_sizes(Metaspace::MetaspaceType type, size_t* chunk_word_size, size_t* class_chunk_word_size) { switch (type) { case Metaspace::BootMetaspaceType: *chunk_word_size = Metaspace::first_chunk_word_size(); *class_chunk_word_size = Metaspace::first_class_chunk_word_size(); break; case Metaspace::ROMetaspaceType: *chunk_word_size = SharedReadOnlySize / wordSize; *class_chunk_word_size = ClassSpecializedChunk; break; case Metaspace::ReadWriteMetaspaceType: *chunk_word_size = SharedReadWriteSize / wordSize; *class_chunk_word_size = ClassSpecializedChunk; break; case Metaspace::AnonymousMetaspaceType: case Metaspace::ReflectionMetaspaceType: *chunk_word_size = SpecializedChunk; *class_chunk_word_size = ClassSpecializedChunk; break; default: *chunk_word_size = SmallChunk; *class_chunk_word_size = ClassSmallChunk; break; } assert(*chunk_word_size != 0 && *class_chunk_word_size != 0, err_msg("Initial chunks sizes bad: data " SIZE_FORMAT " class " SIZE_FORMAT, *chunk_word_size, *class_chunk_word_size)); } size_t SpaceManager::sum_free_in_chunks_in_use() const { MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); size_t free = 0; for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { Metachunk* chunk = chunks_in_use(i); while (chunk != NULL) { free += chunk->free_word_size(); chunk = chunk->next(); } } return free; } size_t SpaceManager::sum_waste_in_chunks_in_use() const { MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); size_t result = 0; for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { result += sum_waste_in_chunks_in_use(i); } return result; } size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const { size_t result = 0; Metachunk* chunk = chunks_in_use(index); // Count the free space in all the chunk but not the // current chunk from which allocations are still being done. while (chunk != NULL) { if (chunk != current_chunk()) { result += chunk->free_word_size(); } chunk = chunk->next(); } return result; } size_t SpaceManager::sum_capacity_in_chunks_in_use() const { // For CMS use "allocated_chunks_words()" which does not need the // Metaspace lock. For the other collectors sum over the // lists. Use both methods as a check that "allocated_chunks_words()" // is correct. That is, sum_capacity_in_chunks() is too expensive // to use in the product and allocated_chunks_words() should be used // but allow for checking that allocated_chunks_words() returns the same // value as sum_capacity_in_chunks_in_use() which is the definitive // answer. if (UseConcMarkSweepGC) { return allocated_chunks_words(); } else { MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); size_t sum = 0; for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { Metachunk* chunk = chunks_in_use(i); while (chunk != NULL) { sum += chunk->capacity_word_size(); chunk = chunk->next(); } } return sum; } } size_t SpaceManager::sum_count_in_chunks_in_use() { size_t count = 0; for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { count = count + sum_count_in_chunks_in_use(i); } return count; } size_t SpaceManager::sum_count_in_chunks_in_use(ChunkIndex i) { size_t count = 0; Metachunk* chunk = chunks_in_use(i); while (chunk != NULL) { count++; chunk = chunk->next(); } return count; } size_t SpaceManager::sum_used_in_chunks_in_use() const { MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); size_t used = 0; for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { Metachunk* chunk = chunks_in_use(i); while (chunk != NULL) { used += chunk->used_word_size(); chunk = chunk->next(); } } return used; } void SpaceManager::locked_print_chunks_in_use_on(outputStream* st) const { for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { Metachunk* chunk = chunks_in_use(i); st->print("SpaceManager: %s " PTR_FORMAT, chunk_size_name(i), chunk); if (chunk != NULL) { st->print_cr(" free " SIZE_FORMAT, chunk->free_word_size()); } else { st->print_cr(""); } } vs_list()->chunk_manager()->locked_print_free_chunks(st); vs_list()->chunk_manager()->locked_print_sum_free_chunks(st); } size_t SpaceManager::calc_chunk_size(size_t word_size) { // Decide between a small chunk and a medium chunk. Up to // _small_chunk_limit small chunks can be allocated but // once a medium chunk has been allocated, no more small // chunks will be allocated. size_t chunk_word_size; if (chunks_in_use(MediumIndex) == NULL && sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit) { chunk_word_size = (size_t) small_chunk_size(); if (word_size + Metachunk::overhead() > small_chunk_size()) { chunk_word_size = medium_chunk_size(); } } else { chunk_word_size = medium_chunk_size(); } // Might still need a humongous chunk. Enforce an // eight word granularity to facilitate reuse (some // wastage but better chance of reuse). size_t if_humongous_sized_chunk = align_size_up(word_size + Metachunk::overhead(), HumongousChunkGranularity); chunk_word_size = MAX2((size_t) chunk_word_size, if_humongous_sized_chunk); assert(!SpaceManager::is_humongous(word_size) || chunk_word_size == if_humongous_sized_chunk, err_msg("Size calculation is wrong, word_size " SIZE_FORMAT " chunk_word_size " SIZE_FORMAT, word_size, chunk_word_size)); if (TraceMetadataHumongousAllocation && SpaceManager::is_humongous(word_size)) { gclog_or_tty->print_cr("Metadata humongous allocation:"); gclog_or_tty->print_cr(" word_size " PTR_FORMAT, word_size); gclog_or_tty->print_cr(" chunk_word_size " PTR_FORMAT, chunk_word_size); gclog_or_tty->print_cr(" chunk overhead " PTR_FORMAT, Metachunk::overhead()); } return chunk_word_size; } MetaWord* SpaceManager::grow_and_allocate(size_t word_size) { assert(vs_list()->current_virtual_space() != NULL, "Should have been set"); assert(current_chunk() == NULL || current_chunk()->allocate(word_size) == NULL, "Don't need to expand"); MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); if (TraceMetadataChunkAllocation && Verbose) { size_t words_left = 0; size_t words_used = 0; if (current_chunk() != NULL) { words_left = current_chunk()->free_word_size(); words_used = current_chunk()->used_word_size(); } gclog_or_tty->print_cr("SpaceManager::grow_and_allocate for " SIZE_FORMAT " words " SIZE_FORMAT " words used " SIZE_FORMAT " words left", word_size, words_used, words_left); } // Get another chunk out of the virtual space size_t grow_chunks_by_words = calc_chunk_size(word_size); Metachunk* next = get_new_chunk(word_size, grow_chunks_by_words); // If a chunk was available, add it to the in-use chunk list // and do an allocation from it. if (next != NULL) { Metadebug::deallocate_chunk_a_lot(this, grow_chunks_by_words); // Add to this manager's list of chunks in use. add_chunk(next, false); return next->allocate(word_size); } return NULL; } void SpaceManager::print_on(outputStream* st) const { for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists ; i = next_chunk_index(i) ) { st->print_cr(" chunks_in_use " PTR_FORMAT " chunk size " PTR_FORMAT, chunks_in_use(i), chunks_in_use(i) == NULL ? 0 : chunks_in_use(i)->word_size()); } st->print_cr(" waste: Small " SIZE_FORMAT " Medium " SIZE_FORMAT " Humongous " SIZE_FORMAT, sum_waste_in_chunks_in_use(SmallIndex), sum_waste_in_chunks_in_use(MediumIndex), sum_waste_in_chunks_in_use(HumongousIndex)); // block free lists if (block_freelists() != NULL) { st->print_cr("total in block free lists " SIZE_FORMAT, block_freelists()->total_size()); } } SpaceManager::SpaceManager(Metaspace::MetadataType mdtype, Mutex* lock, VirtualSpaceList* vs_list) : _vs_list(vs_list), _mdtype(mdtype), _allocated_blocks_words(0), _allocated_chunks_words(0), _allocated_chunks_count(0), _lock(lock) { initialize(); } void SpaceManager::inc_size_metrics(size_t words) { assert_lock_strong(SpaceManager::expand_lock()); // Total of allocated Metachunks and allocated Metachunks count // for each SpaceManager _allocated_chunks_words = _allocated_chunks_words + words; _allocated_chunks_count++; // Global total of capacity in allocated Metachunks MetaspaceAux::inc_capacity(mdtype(), words); // Global total of allocated Metablocks. // used_words_slow() includes the overhead in each // Metachunk so include it in the used when the // Metachunk is first added (so only added once per // Metachunk). MetaspaceAux::inc_used(mdtype(), Metachunk::overhead()); } void SpaceManager::inc_used_metrics(size_t words) { // Add to the per SpaceManager total Atomic::add_ptr(words, &_allocated_blocks_words); // Add to the global total MetaspaceAux::inc_used(mdtype(), words); } void SpaceManager::dec_total_from_size_metrics() { MetaspaceAux::dec_capacity(mdtype(), allocated_chunks_words()); MetaspaceAux::dec_used(mdtype(), allocated_blocks_words()); // Also deduct the overhead per Metachunk MetaspaceAux::dec_used(mdtype(), allocated_chunks_count() * Metachunk::overhead()); } void SpaceManager::initialize() { Metadebug::init_allocation_fail_alot_count(); for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { _chunks_in_use[i] = NULL; } _current_chunk = NULL; if (TraceMetadataChunkAllocation && Verbose) { gclog_or_tty->print_cr("SpaceManager(): " PTR_FORMAT, this); } } void ChunkManager::return_chunks(ChunkIndex index, Metachunk* chunks) { if (chunks == NULL) { return; } ChunkList* list = free_chunks(index); assert(list->size() == chunks->word_size(), "Mismatch in chunk sizes"); assert_lock_strong(SpaceManager::expand_lock()); Metachunk* cur = chunks; // This returns chunks one at a time. If a new // class List can be created that is a base class // of FreeList then something like FreeList::prepend() // can be used in place of this loop while (cur != NULL) { assert(cur->container() != NULL, "Container should have been set"); cur->container()->dec_container_count(); // Capture the next link before it is changed // by the call to return_chunk_at_head(); Metachunk* next = cur->next(); cur->set_is_free(true); list->return_chunk_at_head(cur); cur = next; } } SpaceManager::~SpaceManager() { // This call this->_lock which can't be done while holding expand_lock() assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(), err_msg("sum_capacity_in_chunks_in_use() " SIZE_FORMAT " allocated_chunks_words() " SIZE_FORMAT, sum_capacity_in_chunks_in_use(), allocated_chunks_words())); MutexLockerEx fcl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); ChunkManager* chunk_manager = vs_list()->chunk_manager(); chunk_manager->slow_locked_verify(); dec_total_from_size_metrics(); if (TraceMetadataChunkAllocation && Verbose) { gclog_or_tty->print_cr("~SpaceManager(): " PTR_FORMAT, this); locked_print_chunks_in_use_on(gclog_or_tty); } // Do not mangle freed Metachunks. The chunk size inside Metachunks // is during the freeing of a VirtualSpaceNodes. // Have to update before the chunks_in_use lists are emptied // below. chunk_manager->inc_free_chunks_total(allocated_chunks_words(), sum_count_in_chunks_in_use()); // Add all the chunks in use by this space manager // to the global list of free chunks. // Follow each list of chunks-in-use and add them to the // free lists. Each list is NULL terminated. for (ChunkIndex i = ZeroIndex; i < HumongousIndex; i = next_chunk_index(i)) { if (TraceMetadataChunkAllocation && Verbose) { gclog_or_tty->print_cr("returned %d %s chunks to freelist", sum_count_in_chunks_in_use(i), chunk_size_name(i)); } Metachunk* chunks = chunks_in_use(i); chunk_manager->return_chunks(i, chunks); set_chunks_in_use(i, NULL); if (TraceMetadataChunkAllocation && Verbose) { gclog_or_tty->print_cr("updated freelist count %d %s", chunk_manager->free_chunks(i)->count(), chunk_size_name(i)); } assert(i != HumongousIndex, "Humongous chunks are handled explicitly later"); } // The medium chunk case may be optimized by passing the head and // tail of the medium chunk list to add_at_head(). The tail is often // the current chunk but there are probably exceptions. // Humongous chunks if (TraceMetadataChunkAllocation && Verbose) { gclog_or_tty->print_cr("returned %d %s humongous chunks to dictionary", sum_count_in_chunks_in_use(HumongousIndex), chunk_size_name(HumongousIndex)); gclog_or_tty->print("Humongous chunk dictionary: "); } // Humongous chunks are never the current chunk. Metachunk* humongous_chunks = chunks_in_use(HumongousIndex); while (humongous_chunks != NULL) { #ifdef ASSERT humongous_chunks->set_is_free(true); #endif if (TraceMetadataChunkAllocation && Verbose) { gclog_or_tty->print(PTR_FORMAT " (" SIZE_FORMAT ") ", humongous_chunks, humongous_chunks->word_size()); } assert(humongous_chunks->word_size() == (size_t) align_size_up(humongous_chunks->word_size(), HumongousChunkGranularity), err_msg("Humongous chunk size is wrong: word size " SIZE_FORMAT " granularity %d", humongous_chunks->word_size(), HumongousChunkGranularity)); Metachunk* next_humongous_chunks = humongous_chunks->next(); humongous_chunks->container()->dec_container_count(); chunk_manager->humongous_dictionary()->return_chunk(humongous_chunks); humongous_chunks = next_humongous_chunks; } if (TraceMetadataChunkAllocation && Verbose) { gclog_or_tty->print_cr(""); gclog_or_tty->print_cr("updated dictionary count %d %s", chunk_manager->humongous_dictionary()->total_count(), chunk_size_name(HumongousIndex)); } chunk_manager->slow_locked_verify(); } const char* SpaceManager::chunk_size_name(ChunkIndex index) const { switch (index) { case SpecializedIndex: return "Specialized"; case SmallIndex: return "Small"; case MediumIndex: return "Medium"; case HumongousIndex: return "Humongous"; default: return NULL; } } ChunkIndex ChunkManager::list_index(size_t size) { switch (size) { case SpecializedChunk: assert(SpecializedChunk == ClassSpecializedChunk, "Need branch for ClassSpecializedChunk"); return SpecializedIndex; case SmallChunk: case ClassSmallChunk: return SmallIndex; case MediumChunk: case ClassMediumChunk: return MediumIndex; default: assert(size > MediumChunk || size > ClassMediumChunk, "Not a humongous chunk"); return HumongousIndex; } } void SpaceManager::deallocate(MetaWord* p, size_t word_size) { assert_lock_strong(_lock); size_t raw_word_size = get_raw_word_size(word_size); size_t min_size = TreeChunk::min_size(); assert(raw_word_size >= min_size, err_msg("Should not deallocate dark matter " SIZE_FORMAT "<" SIZE_FORMAT, word_size, min_size)); block_freelists()->return_block(p, raw_word_size); } // Adds a chunk to the list of chunks in use. void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) { assert(new_chunk != NULL, "Should not be NULL"); assert(new_chunk->next() == NULL, "Should not be on a list"); new_chunk->reset_empty(); // Find the correct list and and set the current // chunk for that list. ChunkIndex index = ChunkManager::list_index(new_chunk->word_size()); if (index != HumongousIndex) { set_current_chunk(new_chunk); new_chunk->set_next(chunks_in_use(index)); set_chunks_in_use(index, new_chunk); } else { // For null class loader data and DumpSharedSpaces, the first chunk isn't // small, so small will be null. Link this first chunk as the current // chunk. if (make_current) { // Set as the current chunk but otherwise treat as a humongous chunk. set_current_chunk(new_chunk); } // Link at head. The _current_chunk only points to a humongous chunk for // the null class loader metaspace (class and data virtual space managers) // any humongous chunks so will not point to the tail // of the humongous chunks list. new_chunk->set_next(chunks_in_use(HumongousIndex)); set_chunks_in_use(HumongousIndex, new_chunk); assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency"); } // Add to the running sum of capacity inc_size_metrics(new_chunk->word_size()); assert(new_chunk->is_empty(), "Not ready for reuse"); if (TraceMetadataChunkAllocation && Verbose) { gclog_or_tty->print("SpaceManager::add_chunk: %d) ", sum_count_in_chunks_in_use()); new_chunk->print_on(gclog_or_tty); if (vs_list() != NULL) { vs_list()->chunk_manager()->locked_print_free_chunks(tty); } } } Metachunk* SpaceManager::get_new_chunk(size_t word_size, size_t grow_chunks_by_words) { Metachunk* next = vs_list()->get_new_chunk(word_size, grow_chunks_by_words, medium_chunk_bunch()); if (TraceMetadataHumongousAllocation && SpaceManager::is_humongous(next->word_size())) { gclog_or_tty->print_cr(" new humongous chunk word size " PTR_FORMAT, next->word_size()); } return next; } MetaWord* SpaceManager::allocate(size_t word_size) { MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); size_t raw_word_size = get_raw_word_size(word_size); BlockFreelist* fl = block_freelists(); MetaWord* p = NULL; // Allocation from the dictionary is expensive in the sense that // the dictionary has to be searched for a size. Don't allocate // from the dictionary until it starts to get fat. Is this // a reasonable policy? Maybe an skinny dictionary is fast enough // for allocations. Do some profiling. JJJ if (fl->total_size() > allocation_from_dictionary_limit) { p = fl->get_block(raw_word_size); } if (p == NULL) { p = allocate_work(raw_word_size); } Metadebug::deallocate_block_a_lot(this, raw_word_size); return p; } // Returns the address of spaced allocated for "word_size". // This methods does not know about blocks (Metablocks) MetaWord* SpaceManager::allocate_work(size_t word_size) { assert_lock_strong(_lock); #ifdef ASSERT if (Metadebug::test_metadata_failure()) { return NULL; } #endif // Is there space in the current chunk? MetaWord* result = NULL; // For DumpSharedSpaces, only allocate out of the current chunk which is // never null because we gave it the size we wanted. Caller reports out // of memory if this returns null. if (DumpSharedSpaces) { assert(current_chunk() != NULL, "should never happen"); inc_used_metrics(word_size); return current_chunk()->allocate(word_size); // caller handles null result } if (current_chunk() != NULL) { result = current_chunk()->allocate(word_size); } if (result == NULL) { result = grow_and_allocate(word_size); } if (result != 0) { inc_used_metrics(word_size); assert(result != (MetaWord*) chunks_in_use(MediumIndex), "Head of the list is being allocated"); } return result; } void SpaceManager::verify() { // If there are blocks in the dictionary, then // verfication of chunks does not work since // being in the dictionary alters a chunk. if (block_freelists()->total_size() == 0) { for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { Metachunk* curr = chunks_in_use(i); while (curr != NULL) { curr->verify(); verify_chunk_size(curr); curr = curr->next(); } } } } void SpaceManager::verify_chunk_size(Metachunk* chunk) { assert(is_humongous(chunk->word_size()) || chunk->word_size() == medium_chunk_size() || chunk->word_size() == small_chunk_size() || chunk->word_size() == specialized_chunk_size(), "Chunk size is wrong"); return; } #ifdef ASSERT void SpaceManager::verify_allocated_blocks_words() { // Verification is only guaranteed at a safepoint. assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(), "Verification can fail if the applications is running"); assert(allocated_blocks_words() == sum_used_in_chunks_in_use(), err_msg("allocation total is not consistent " SIZE_FORMAT " vs " SIZE_FORMAT, allocated_blocks_words(), sum_used_in_chunks_in_use())); } #endif void SpaceManager::dump(outputStream* const out) const { size_t curr_total = 0; size_t waste = 0; uint i = 0; size_t used = 0; size_t capacity = 0; // Add up statistics for all chunks in this SpaceManager. for (ChunkIndex index = ZeroIndex; index < NumberOfInUseLists; index = next_chunk_index(index)) { for (Metachunk* curr = chunks_in_use(index); curr != NULL; curr = curr->next()) { out->print("%d) ", i++); curr->print_on(out); if (TraceMetadataChunkAllocation && Verbose) { block_freelists()->print_on(out); } curr_total += curr->word_size(); used += curr->used_word_size(); capacity += curr->capacity_word_size(); waste += curr->free_word_size() + curr->overhead();; } } size_t free = current_chunk() == NULL ? 0 : current_chunk()->free_word_size(); // Free space isn't wasted. waste -= free; out->print_cr("total of all chunks " SIZE_FORMAT " used " SIZE_FORMAT " free " SIZE_FORMAT " capacity " SIZE_FORMAT " waste " SIZE_FORMAT, curr_total, used, free, capacity, waste); } #ifndef PRODUCT void SpaceManager::mangle_freed_chunks() { for (ChunkIndex index = ZeroIndex; index < NumberOfInUseLists; index = next_chunk_index(index)) { for (Metachunk* curr = chunks_in_use(index); curr != NULL; curr = curr->next()) { curr->mangle(); } } } #endif // PRODUCT // MetaspaceAux size_t MetaspaceAux::_allocated_capacity_words[] = {0, 0}; size_t MetaspaceAux::_allocated_used_words[] = {0, 0}; size_t MetaspaceAux::free_bytes(Metaspace::MetadataType mdtype) { VirtualSpaceList* list = Metaspace::get_space_list(mdtype); return list == NULL ? 0 : list->free_bytes(); } size_t MetaspaceAux::free_bytes() { return free_bytes(Metaspace::ClassType) + free_bytes(Metaspace::NonClassType); } void MetaspaceAux::dec_capacity(Metaspace::MetadataType mdtype, size_t words) { assert_lock_strong(SpaceManager::expand_lock()); assert(words <= allocated_capacity_words(mdtype), err_msg("About to decrement below 0: words " SIZE_FORMAT " is greater than _allocated_capacity_words[%u] " SIZE_FORMAT, words, mdtype, allocated_capacity_words(mdtype))); _allocated_capacity_words[mdtype] -= words; } void MetaspaceAux::inc_capacity(Metaspace::MetadataType mdtype, size_t words) { assert_lock_strong(SpaceManager::expand_lock()); // Needs to be atomic _allocated_capacity_words[mdtype] += words; } void MetaspaceAux::dec_used(Metaspace::MetadataType mdtype, size_t words) { assert(words <= allocated_used_words(mdtype), err_msg("About to decrement below 0: words " SIZE_FORMAT " is greater than _allocated_used_words[%u] " SIZE_FORMAT, words, mdtype, allocated_used_words(mdtype))); // For CMS deallocation of the Metaspaces occurs during the // sweep which is a concurrent phase. Protection by the expand_lock() // is not enough since allocation is on a per Metaspace basis // and protected by the Metaspace lock. jlong minus_words = (jlong) - (jlong) words; Atomic::add_ptr(minus_words, &_allocated_used_words[mdtype]); } void MetaspaceAux::inc_used(Metaspace::MetadataType mdtype, size_t words) { // _allocated_used_words tracks allocations for // each piece of metadata. Those allocations are // generally done concurrently by different application // threads so must be done atomically. Atomic::add_ptr(words, &_allocated_used_words[mdtype]); } size_t MetaspaceAux::used_bytes_slow(Metaspace::MetadataType mdtype) { size_t used = 0; ClassLoaderDataGraphMetaspaceIterator iter; while (iter.repeat()) { Metaspace* msp = iter.get_next(); // Sum allocated_blocks_words for each metaspace if (msp != NULL) { used += msp->used_words_slow(mdtype); } } return used * BytesPerWord; } size_t MetaspaceAux::free_in_bytes(Metaspace::MetadataType mdtype) { size_t free = 0; ClassLoaderDataGraphMetaspaceIterator iter; while (iter.repeat()) { Metaspace* msp = iter.get_next(); if (msp != NULL) { free += msp->free_words(mdtype); } } return free * BytesPerWord; } size_t MetaspaceAux::capacity_bytes_slow(Metaspace::MetadataType mdtype) { if ((mdtype == Metaspace::ClassType) && !Metaspace::using_class_space()) { return 0; } // Don't count the space in the freelists. That space will be // added to the capacity calculation as needed. size_t capacity = 0; ClassLoaderDataGraphMetaspaceIterator iter; while (iter.repeat()) { Metaspace* msp = iter.get_next(); if (msp != NULL) { capacity += msp->capacity_words_slow(mdtype); } } return capacity * BytesPerWord; } size_t MetaspaceAux::reserved_in_bytes(Metaspace::MetadataType mdtype) { VirtualSpaceList* list = Metaspace::get_space_list(mdtype); return list == NULL ? 0 : list->virtual_space_total(); } size_t MetaspaceAux::min_chunk_size() { return Metaspace::first_chunk_word_size(); } size_t MetaspaceAux::free_chunks_total(Metaspace::MetadataType mdtype) { VirtualSpaceList* list = Metaspace::get_space_list(mdtype); if (list == NULL) { return 0; } ChunkManager* chunk = list->chunk_manager(); chunk->slow_verify(); return chunk->free_chunks_total(); } size_t MetaspaceAux::free_chunks_total_in_bytes(Metaspace::MetadataType mdtype) { return free_chunks_total(mdtype) * BytesPerWord; } size_t MetaspaceAux::free_chunks_total() { return free_chunks_total(Metaspace::ClassType) + free_chunks_total(Metaspace::NonClassType); } size_t MetaspaceAux::free_chunks_total_in_bytes() { return free_chunks_total() * BytesPerWord; } void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) { gclog_or_tty->print(", [Metaspace:"); if (PrintGCDetails && Verbose) { gclog_or_tty->print(" " SIZE_FORMAT "->" SIZE_FORMAT "(" SIZE_FORMAT ")", prev_metadata_used, allocated_used_bytes(), reserved_in_bytes()); } else { gclog_or_tty->print(" " SIZE_FORMAT "K" "->" SIZE_FORMAT "K" "(" SIZE_FORMAT "K)", prev_metadata_used / K, allocated_used_bytes() / K, reserved_in_bytes()/ K); } gclog_or_tty->print("]"); } // This is printed when PrintGCDetails void MetaspaceAux::print_on(outputStream* out) { Metaspace::MetadataType nct = Metaspace::NonClassType; out->print_cr(" Metaspace total " SIZE_FORMAT "K, used " SIZE_FORMAT "K," " reserved " SIZE_FORMAT "K", allocated_capacity_bytes()/K, allocated_used_bytes()/K, reserved_in_bytes()/K); out->print_cr(" data space " SIZE_FORMAT "K, used " SIZE_FORMAT "K," " reserved " SIZE_FORMAT "K", allocated_capacity_bytes(nct)/K, allocated_used_bytes(nct)/K, reserved_in_bytes(nct)/K); if (Metaspace::using_class_space()) { Metaspace::MetadataType ct = Metaspace::ClassType; out->print_cr(" class space " SIZE_FORMAT "K, used " SIZE_FORMAT "K," " reserved " SIZE_FORMAT "K", allocated_capacity_bytes(ct)/K, allocated_used_bytes(ct)/K, reserved_in_bytes(ct)/K); } } // Print information for class space and data space separately. // This is almost the same as above. void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) { size_t free_chunks_capacity_bytes = free_chunks_total_in_bytes(mdtype); size_t capacity_bytes = capacity_bytes_slow(mdtype); size_t used_bytes = used_bytes_slow(mdtype); size_t free_bytes = free_in_bytes(mdtype); size_t used_and_free = used_bytes + free_bytes + free_chunks_capacity_bytes; out->print_cr(" Chunk accounting: used in chunks " SIZE_FORMAT "K + unused in chunks " SIZE_FORMAT "K + " " capacity in free chunks " SIZE_FORMAT "K = " SIZE_FORMAT "K capacity in allocated chunks " SIZE_FORMAT "K", used_bytes / K, free_bytes / K, free_chunks_capacity_bytes / K, used_and_free / K, capacity_bytes / K); // Accounting can only be correct if we got the values during a safepoint assert(!SafepointSynchronize::is_at_safepoint() || used_and_free == capacity_bytes, "Accounting is wrong"); } // Print total fragmentation for class metaspaces void MetaspaceAux::print_class_waste(outputStream* out) { assert(Metaspace::using_class_space(), "class metaspace not used"); size_t cls_specialized_waste = 0, cls_small_waste = 0, cls_medium_waste = 0; size_t cls_specialized_count = 0, cls_small_count = 0, cls_medium_count = 0, cls_humongous_count = 0; ClassLoaderDataGraphMetaspaceIterator iter; while (iter.repeat()) { Metaspace* msp = iter.get_next(); if (msp != NULL) { cls_specialized_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SpecializedIndex); cls_specialized_count += msp->class_vsm()->sum_count_in_chunks_in_use(SpecializedIndex); cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex); cls_small_count += msp->class_vsm()->sum_count_in_chunks_in_use(SmallIndex); cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex); cls_medium_count += msp->class_vsm()->sum_count_in_chunks_in_use(MediumIndex); cls_humongous_count += msp->class_vsm()->sum_count_in_chunks_in_use(HumongousIndex); } } out->print_cr(" class: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", " SIZE_FORMAT " small(s) " SIZE_FORMAT ", " SIZE_FORMAT " medium(s) " SIZE_FORMAT ", " "large count " SIZE_FORMAT, cls_specialized_count, cls_specialized_waste, cls_small_count, cls_small_waste, cls_medium_count, cls_medium_waste, cls_humongous_count); } // Print total fragmentation for data and class metaspaces separately void MetaspaceAux::print_waste(outputStream* out) { size_t specialized_waste = 0, small_waste = 0, medium_waste = 0; size_t specialized_count = 0, small_count = 0, medium_count = 0, humongous_count = 0; ClassLoaderDataGraphMetaspaceIterator iter; while (iter.repeat()) { Metaspace* msp = iter.get_next(); if (msp != NULL) { specialized_waste += msp->vsm()->sum_waste_in_chunks_in_use(SpecializedIndex); specialized_count += msp->vsm()->sum_count_in_chunks_in_use(SpecializedIndex); small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex); small_count += msp->vsm()->sum_count_in_chunks_in_use(SmallIndex); medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex); medium_count += msp->vsm()->sum_count_in_chunks_in_use(MediumIndex); humongous_count += msp->vsm()->sum_count_in_chunks_in_use(HumongousIndex); } } out->print_cr("Total fragmentation waste (words) doesn't count free space"); out->print_cr(" data: " SIZE_FORMAT " specialized(s) " SIZE_FORMAT ", " SIZE_FORMAT " small(s) " SIZE_FORMAT ", " SIZE_FORMAT " medium(s) " SIZE_FORMAT ", " "large count " SIZE_FORMAT, specialized_count, specialized_waste, small_count, small_waste, medium_count, medium_waste, humongous_count); if (Metaspace::using_class_space()) { print_class_waste(out); } } // Dump global metaspace things from the end of ClassLoaderDataGraph void MetaspaceAux::dump(outputStream* out) { out->print_cr("All Metaspace:"); out->print("data space: "); print_on(out, Metaspace::NonClassType); out->print("class space: "); print_on(out, Metaspace::ClassType); print_waste(out); } void MetaspaceAux::verify_free_chunks() { Metaspace::space_list()->chunk_manager()->verify(); if (Metaspace::using_class_space()) { Metaspace::class_space_list()->chunk_manager()->verify(); } } void MetaspaceAux::verify_capacity() { #ifdef ASSERT size_t running_sum_capacity_bytes = allocated_capacity_bytes(); // For purposes of the running sum of capacity, verify against capacity size_t capacity_in_use_bytes = capacity_bytes_slow(); assert(running_sum_capacity_bytes == capacity_in_use_bytes, err_msg("allocated_capacity_words() * BytesPerWord " SIZE_FORMAT " capacity_bytes_slow()" SIZE_FORMAT, running_sum_capacity_bytes, capacity_in_use_bytes)); for (Metaspace::MetadataType i = Metaspace::ClassType; i < Metaspace:: MetadataTypeCount; i = (Metaspace::MetadataType)(i + 1)) { size_t capacity_in_use_bytes = capacity_bytes_slow(i); assert(allocated_capacity_bytes(i) == capacity_in_use_bytes, err_msg("allocated_capacity_bytes(%u) " SIZE_FORMAT " capacity_bytes_slow(%u)" SIZE_FORMAT, i, allocated_capacity_bytes(i), i, capacity_in_use_bytes)); } #endif } void MetaspaceAux::verify_used() { #ifdef ASSERT size_t running_sum_used_bytes = allocated_used_bytes(); // For purposes of the running sum of used, verify against used size_t used_in_use_bytes = used_bytes_slow(); assert(allocated_used_bytes() == used_in_use_bytes, err_msg("allocated_used_bytes() " SIZE_FORMAT " used_bytes_slow()" SIZE_FORMAT, allocated_used_bytes(), used_in_use_bytes)); for (Metaspace::MetadataType i = Metaspace::ClassType; i < Metaspace:: MetadataTypeCount; i = (Metaspace::MetadataType)(i + 1)) { size_t used_in_use_bytes = used_bytes_slow(i); assert(allocated_used_bytes(i) == used_in_use_bytes, err_msg("allocated_used_bytes(%u) " SIZE_FORMAT " used_bytes_slow(%u)" SIZE_FORMAT, i, allocated_used_bytes(i), i, used_in_use_bytes)); } #endif } void MetaspaceAux::verify_metrics() { verify_capacity(); verify_used(); } // Metaspace methods size_t Metaspace::_first_chunk_word_size = 0; size_t Metaspace::_first_class_chunk_word_size = 0; Metaspace::Metaspace(Mutex* lock, MetaspaceType type) { initialize(lock, type); } Metaspace::~Metaspace() { delete _vsm; if (using_class_space()) { delete _class_vsm; } } VirtualSpaceList* Metaspace::_space_list = NULL; VirtualSpaceList* Metaspace::_class_space_list = NULL; #define VIRTUALSPACEMULTIPLIER 2 #ifdef _LP64 void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) { // Figure out the narrow_klass_base and the narrow_klass_shift. The // narrow_klass_base is the lower of the metaspace base and the cds base // (if cds is enabled). The narrow_klass_shift depends on the distance // between the lower base and higher address. address lower_base; address higher_address; if (UseSharedSpaces) { higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()), (address)(metaspace_base + class_metaspace_size())); lower_base = MIN2(metaspace_base, cds_base); } else { higher_address = metaspace_base + class_metaspace_size(); lower_base = metaspace_base; } Universe::set_narrow_klass_base(lower_base); if ((uint64_t)(higher_address - lower_base) < (uint64_t)max_juint) { Universe::set_narrow_klass_shift(0); } else { assert(!UseSharedSpaces, "Cannot shift with UseSharedSpaces"); Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes); } } // Return TRUE if the specified metaspace_base and cds_base are close enough // to work with compressed klass pointers. bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) { assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS"); assert(UseCompressedKlassPointers, "Only use with CompressedKlassPtrs"); address lower_base = MIN2((address)metaspace_base, cds_base); address higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()), (address)(metaspace_base + class_metaspace_size())); return ((uint64_t)(higher_address - lower_base) < (uint64_t)max_juint); } // Try to allocate the metaspace at the requested addr. void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) { assert(using_class_space(), "called improperly"); assert(UseCompressedKlassPointers, "Only use with CompressedKlassPtrs"); assert(class_metaspace_size() < KlassEncodingMetaspaceMax, "Metaspace size is too big"); ReservedSpace metaspace_rs = ReservedSpace(class_metaspace_size(), os::vm_allocation_granularity(), false, requested_addr, 0); if (!metaspace_rs.is_reserved()) { if (UseSharedSpaces) { // Keep trying to allocate the metaspace, increasing the requested_addr // by 1GB each time, until we reach an address that will no longer allow // use of CDS with compressed klass pointers. char *addr = requested_addr; while (!metaspace_rs.is_reserved() && (addr + 1*G > addr) && can_use_cds_with_metaspace_addr(addr + 1*G, cds_base)) { addr = addr + 1*G; metaspace_rs = ReservedSpace(class_metaspace_size(), os::vm_allocation_granularity(), false, addr, 0); } } // If no successful allocation then try to allocate the space anywhere. If // that fails then OOM doom. At this point we cannot try allocating the // metaspace as if UseCompressedKlassPointers is off because too much // initialization has happened that depends on UseCompressedKlassPointers. // So, UseCompressedKlassPointers cannot be turned off at this point. if (!metaspace_rs.is_reserved()) { metaspace_rs = ReservedSpace(class_metaspace_size(), os::vm_allocation_granularity(), false); if (!metaspace_rs.is_reserved()) { vm_exit_during_initialization(err_msg("Could not allocate metaspace: %d bytes", class_metaspace_size())); } } } // If we got here then the metaspace got allocated. MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass); // Verify that we can use shared spaces. Otherwise, turn off CDS. if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) { FileMapInfo::stop_sharing_and_unmap( "Could not allocate metaspace at a compatible address"); } set_narrow_klass_base_and_shift((address)metaspace_rs.base(), UseSharedSpaces ? (address)cds_base : 0); initialize_class_space(metaspace_rs); if (PrintCompressedOopsMode || (PrintMiscellaneous && Verbose)) { gclog_or_tty->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: " SIZE_FORMAT, Universe::narrow_klass_base(), Universe::narrow_klass_shift()); gclog_or_tty->print_cr("Metaspace Size: " SIZE_FORMAT " Address: " PTR_FORMAT " Req Addr: " PTR_FORMAT, class_metaspace_size(), metaspace_rs.base(), requested_addr); } } // For UseCompressedKlassPointers the class space is reserved above the top of // the Java heap. The argument passed in is at the base of the compressed space. void Metaspace::initialize_class_space(ReservedSpace rs) { // The reserved space size may be bigger because of alignment, esp with UseLargePages assert(rs.size() >= ClassMetaspaceSize, err_msg(SIZE_FORMAT " != " UINTX_FORMAT, rs.size(), ClassMetaspaceSize)); assert(using_class_space(), "Must be using class space"); _class_space_list = new VirtualSpaceList(rs); } #endif void Metaspace::global_initialize() { // Initialize the alignment for shared spaces. int max_alignment = os::vm_page_size(); size_t cds_total = 0; set_class_metaspace_size(align_size_up(ClassMetaspaceSize, os::vm_allocation_granularity())); MetaspaceShared::set_max_alignment(max_alignment); if (DumpSharedSpaces) { SharedReadOnlySize = align_size_up(SharedReadOnlySize, max_alignment); SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment); SharedMiscDataSize = align_size_up(SharedMiscDataSize, max_alignment); SharedMiscCodeSize = align_size_up(SharedMiscCodeSize, max_alignment); // Initialize with the sum of the shared space sizes. The read-only // and read write metaspace chunks will be allocated out of this and the // remainder is the misc code and data chunks. cds_total = FileMapInfo::shared_spaces_size(); _space_list = new VirtualSpaceList(cds_total/wordSize); #ifdef _LP64 // Set the compressed klass pointer base so that decoding of these pointers works // properly when creating the shared archive. assert(UseCompressedOops && UseCompressedKlassPointers, "UseCompressedOops and UseCompressedKlassPointers must be set"); Universe::set_narrow_klass_base((address)_space_list->current_virtual_space()->bottom()); if (TraceMetavirtualspaceAllocation && Verbose) { gclog_or_tty->print_cr("Setting_narrow_klass_base to Address: " PTR_FORMAT, _space_list->current_virtual_space()->bottom()); } // Set the shift to zero. assert(class_metaspace_size() < (uint64_t)(max_juint) - cds_total, "CDS region is too large"); Universe::set_narrow_klass_shift(0); #endif } else { // If using shared space, open the file that contains the shared space // and map in the memory before initializing the rest of metaspace (so // the addresses don't conflict) address cds_address = NULL; if (UseSharedSpaces) { FileMapInfo* mapinfo = new FileMapInfo(); memset(mapinfo, 0, sizeof(FileMapInfo)); // Open the shared archive file, read and validate the header. If // initialization fails, shared spaces [UseSharedSpaces] are // disabled and the file is closed. // Map in spaces now also if (mapinfo->initialize() && MetaspaceShared::map_shared_spaces(mapinfo)) { FileMapInfo::set_current_info(mapinfo); } else { assert(!mapinfo->is_open() && !UseSharedSpaces, "archive file not closed or shared spaces not disabled."); } cds_total = FileMapInfo::shared_spaces_size(); cds_address = (address)mapinfo->region_base(0); } #ifdef _LP64 // If UseCompressedKlassPointers is set then allocate the metaspace area // above the heap and above the CDS area (if it exists). if (using_class_space()) { if (UseSharedSpaces) { allocate_metaspace_compressed_klass_ptrs((char *)(cds_address + cds_total), cds_address); } else { allocate_metaspace_compressed_klass_ptrs((char *)CompressedKlassPointersBase, 0); } } #endif // Initialize these before initializing the VirtualSpaceList _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord; _first_chunk_word_size = align_word_size_up(_first_chunk_word_size); // Make the first class chunk bigger than a medium chunk so it's not put // on the medium chunk list. The next chunk will be small and progress // from there. This size calculated by -version. _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6, (ClassMetaspaceSize/BytesPerWord)*2); _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size); // Arbitrarily set the initial virtual space to a multiple // of the boot class loader size. size_t word_size = VIRTUALSPACEMULTIPLIER * first_chunk_word_size(); // Initialize the list of virtual spaces. _space_list = new VirtualSpaceList(word_size); } } void Metaspace::initialize(Mutex* lock, MetaspaceType type) { assert(space_list() != NULL, "Metadata VirtualSpaceList has not been initialized"); _vsm = new SpaceManager(NonClassType, lock, space_list()); if (_vsm == NULL) { return; } size_t word_size; size_t class_word_size; vsm()->get_initial_chunk_sizes(type, &word_size, &class_word_size); if (using_class_space()) { assert(class_space_list() != NULL, "Class VirtualSpaceList has not been initialized"); // Allocate SpaceManager for classes. _class_vsm = new SpaceManager(ClassType, lock, class_space_list()); if (_class_vsm == NULL) { return; } } MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); // Allocate chunk for metadata objects Metachunk* new_chunk = space_list()->get_initialization_chunk(word_size, vsm()->medium_chunk_bunch()); assert(!DumpSharedSpaces || new_chunk != NULL, "should have enough space for both chunks"); if (new_chunk != NULL) { // Add to this manager's list of chunks in use and current_chunk(). vsm()->add_chunk(new_chunk, true); } // Allocate chunk for class metadata objects if (using_class_space()) { Metachunk* class_chunk = class_space_list()->get_initialization_chunk(class_word_size, class_vsm()->medium_chunk_bunch()); if (class_chunk != NULL) { class_vsm()->add_chunk(class_chunk, true); } } _alloc_record_head = NULL; _alloc_record_tail = NULL; } size_t Metaspace::align_word_size_up(size_t word_size) { size_t byte_size = word_size * wordSize; return ReservedSpace::allocation_align_size_up(byte_size) / wordSize; } MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) { // DumpSharedSpaces doesn't use class metadata area (yet) // Also, don't use class_vsm() unless UseCompressedKlassPointers is true. if (mdtype == ClassType && using_class_space()) { return class_vsm()->allocate(word_size); } else { return vsm()->allocate(word_size); } } MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) { MetaWord* result; MetaspaceGC::set_expand_after_GC(true); size_t before_inc = MetaspaceGC::capacity_until_GC(); size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size) * BytesPerWord; MetaspaceGC::inc_capacity_until_GC(delta_bytes); if (PrintGCDetails && Verbose) { gclog_or_tty->print_cr("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before_inc, MetaspaceGC::capacity_until_GC()); } result = allocate(word_size, mdtype); return result; } // Space allocated in the Metaspace. This may // be across several metadata virtual spaces. char* Metaspace::bottom() const { assert(DumpSharedSpaces, "only useful and valid for dumping shared spaces"); return (char*)vsm()->current_chunk()->bottom(); } size_t Metaspace::used_words_slow(MetadataType mdtype) const { if (mdtype == ClassType) { return using_class_space() ? class_vsm()->sum_used_in_chunks_in_use() : 0; } else { return vsm()->sum_used_in_chunks_in_use(); // includes overhead! } } size_t Metaspace::free_words(MetadataType mdtype) const { if (mdtype == ClassType) { return using_class_space() ? class_vsm()->sum_free_in_chunks_in_use() : 0; } else { return vsm()->sum_free_in_chunks_in_use(); } } // Space capacity in the Metaspace. It includes // space in the list of chunks from which allocations // have been made. Don't include space in the global freelist and // in the space available in the dictionary which // is already counted in some chunk. size_t Metaspace::capacity_words_slow(MetadataType mdtype) const { if (mdtype == ClassType) { return using_class_space() ? class_vsm()->sum_capacity_in_chunks_in_use() : 0; } else { return vsm()->sum_capacity_in_chunks_in_use(); } } size_t Metaspace::used_bytes_slow(MetadataType mdtype) const { return used_words_slow(mdtype) * BytesPerWord; } size_t Metaspace::capacity_bytes_slow(MetadataType mdtype) const { return capacity_words_slow(mdtype) * BytesPerWord; } void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) { if (SafepointSynchronize::is_at_safepoint()) { assert(Thread::current()->is_VM_thread(), "should be the VM thread"); // Don't take Heap_lock MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag); if (word_size < TreeChunk::min_size()) { // Dark matter. Too small for dictionary. #ifdef ASSERT Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5); #endif return; } if (is_class && using_class_space()) { class_vsm()->deallocate(ptr, word_size); } else { vsm()->deallocate(ptr, word_size); } } else { MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag); if (word_size < TreeChunk::min_size()) { // Dark matter. Too small for dictionary. #ifdef ASSERT Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5); #endif return; } if (is_class && using_class_space()) { class_vsm()->deallocate(ptr, word_size); } else { vsm()->deallocate(ptr, word_size); } } } Metablock* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size, bool read_only, MetaspaceObj::Type type, TRAPS) { if (HAS_PENDING_EXCEPTION) { assert(false, "Should not allocate with exception pending"); return NULL; // caller does a CHECK_NULL too } MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType; // SSS: Should we align the allocations and make sure the sizes are aligned. MetaWord* result = NULL; assert(loader_data != NULL, "Should never pass around a NULL loader_data. " "ClassLoaderData::the_null_class_loader_data() should have been used."); // Allocate in metaspaces without taking out a lock, because it deadlocks // with the SymbolTable_lock. Dumping is single threaded for now. We'll have // to revisit this for application class data sharing. if (DumpSharedSpaces) { assert(type > MetaspaceObj::UnknownType && type < MetaspaceObj::_number_of_types, "sanity"); Metaspace* space = read_only ? loader_data->ro_metaspace() : loader_data->rw_metaspace(); result = space->allocate(word_size, NonClassType); if (result == NULL) { report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite); } else { space->record_allocation(result, type, space->vsm()->get_raw_word_size(word_size)); } return Metablock::initialize(result, word_size); } result = loader_data->metaspace_non_null()->allocate(word_size, mdtype); if (result == NULL) { // Try to clean out some memory and retry. result = Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation( loader_data, word_size, mdtype); // If result is still null, we are out of memory. if (result == NULL) { if (Verbose && TraceMetadataChunkAllocation) { gclog_or_tty->print_cr("Metaspace allocation failed for size " SIZE_FORMAT, word_size); if (loader_data->metaspace_or_null() != NULL) loader_data->dump(gclog_or_tty); MetaspaceAux::dump(gclog_or_tty); } // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support const char* space_string = (mdtype == ClassType) ? "Class Metadata space" : "Metadata space"; report_java_out_of_memory(space_string); if (JvmtiExport::should_post_resource_exhausted()) { JvmtiExport::post_resource_exhausted( JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR, space_string); } if (mdtype == ClassType) { THROW_OOP_0(Universe::out_of_memory_error_class_metaspace()); } else { THROW_OOP_0(Universe::out_of_memory_error_metaspace()); } } } return Metablock::initialize(result, word_size); } void Metaspace::record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size) { assert(DumpSharedSpaces, "sanity"); AllocRecord *rec = new AllocRecord((address)ptr, type, (int)word_size * HeapWordSize); if (_alloc_record_head == NULL) { _alloc_record_head = _alloc_record_tail = rec; } else { _alloc_record_tail->_next = rec; _alloc_record_tail = rec; } } void Metaspace::iterate(Metaspace::AllocRecordClosure *closure) { assert(DumpSharedSpaces, "unimplemented for !DumpSharedSpaces"); address last_addr = (address)bottom(); for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) { address ptr = rec->_ptr; if (last_addr < ptr) { closure->doit(last_addr, MetaspaceObj::UnknownType, ptr - last_addr); } closure->doit(ptr, rec->_type, rec->_byte_size); last_addr = ptr + rec->_byte_size; } address top = ((address)bottom()) + used_bytes_slow(Metaspace::NonClassType); if (last_addr < top) { closure->doit(last_addr, MetaspaceObj::UnknownType, top - last_addr); } } void Metaspace::purge() { MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); space_list()->purge(); if (using_class_space()) { class_space_list()->purge(); } } void Metaspace::print_on(outputStream* out) const { // Print both class virtual space counts and metaspace. if (Verbose) { vsm()->print_on(out); if (using_class_space()) { class_vsm()->print_on(out); } } } bool Metaspace::contains(const void * ptr) { if (MetaspaceShared::is_in_shared_space(ptr)) { return true; } // This is checked while unlocked. As long as the virtualspaces are added // at the end, the pointer will be in one of them. The virtual spaces // aren't deleted presently. When they are, some sort of locking might // be needed. Note, locking this can cause inversion problems with the // caller in MetaspaceObj::is_metadata() function. return space_list()->contains(ptr) || (using_class_space() && class_space_list()->contains(ptr)); } void Metaspace::verify() { vsm()->verify(); if (using_class_space()) { class_vsm()->verify(); } } void Metaspace::dump(outputStream* const out) const { out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, vsm()); vsm()->dump(out); if (using_class_space()) { out->print_cr("\nClass space manager: " INTPTR_FORMAT, class_vsm()); class_vsm()->dump(out); } }