Mercurial > hg > truffle
view src/share/vm/memory/metaspace.cpp @ 7252:73139223837c
Merge
author | Lukas Stadler <lukas.stadler@jku.at> |
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date | Mon, 17 Dec 2012 17:42:27 +0100 |
parents | eade6b2e4782 |
children | c71879335291 |
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/* * Copyright (c) 2011, 2012, 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/mutex.hpp" #include "runtime/orderAccess.hpp" #include "services/memTracker.hpp" #include "utilities/copy.hpp" #include "utilities/debug.hpp" typedef BinaryTreeDictionary<Metablock, FreeList> BlockTreeDictionary; typedef BinaryTreeDictionary<Metachunk, FreeList> 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; const size_t metadata_deallocate = 0xf5f5f5f5; MetaWord* last_allocated = 0; // Used in declarations in SpaceManager and ChunkManager enum ChunkIndex { SmallIndex = 0, MediumIndex = 1, HumongousIndex = 2, NumberOfFreeLists = 2, NumberOfInUseLists = 3 }; 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. // Pointer to list of Metachunks. class ChunkList VALUE_OBJ_CLASS_SPEC { // List of free chunks Metachunk* _head; public: // Constructor ChunkList() : _head(NULL) {} // Accessors Metachunk* head() { return _head; } void set_head(Metachunk* v) { _head = v; } // Link at head of the list void add_at_head(Metachunk* head, Metachunk* tail); void add_at_head(Metachunk* head); size_t sum_list_size(); size_t sum_list_count(); size_t sum_list_capacity(); }; // 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. // 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); // 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); } ChunkList* free_medium_chunks() { return &_free_chunks[1]; } ChunkList* free_small_chunks() { return &_free_chunks[0]; } 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<mtClass> { friend class VirtualSpaceList; // Link to next VirtualSpaceNode VirtualSpaceNode* _next; // total in the VirtualSpace MemRegion _reserved; ReservedSpace _rs; VirtualSpace _virtual_space; MetaWord* _top; // Convenience functions for logical bottom and end MetaWord* bottom() const { return (MetaWord*) _virtual_space.low(); } MetaWord* end() const { return (MetaWord*) _virtual_space.high(); } // Convenience functions to access the _virtual_space char* low() const { return virtual_space()->low(); } char* high() const { return virtual_space()->high(); } public: VirtualSpaceNode(size_t byte_size); VirtualSpaceNode(ReservedSpace rs) : _top(NULL), _next(NULL), _rs(rs) {} ~VirtualSpaceNode(); // 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 virtual space 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; } // used and capacity in this single entry in the list size_t used_words_in_vs() const; size_t capacity_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); #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(0) { // This allocates memory with mmap. For DumpSharedspaces, allocate the // space at low memory so that other shared images don't conflict. // This is the same address as memory needed for UseCompressedOops but // compressed oops don't work with CDS (offsets in metadata are wrong), so // borrow the same address. if (DumpSharedSpaces) { char* shared_base = (char*)HeapBaseMinAddress; _rs = ReservedSpace(byte_size, 0, false, shared_base, 0); if (_rs.is_reserved()) { assert(_rs.base() == shared_base, "should match"); } else { // If we are dumping the heap, then allocate a wasted block of address // space in order to push the heap to a lower address. This extra // address range allows for other (or larger) libraries to be loaded // without them occupying the space required for the shared spaces. uintx reserved = 0; uintx block_size = 64*1024*1024; while (reserved < SharedDummyBlockSize) { char* dummy = os::reserve_memory(block_size); reserved += block_size; } _rs = ReservedSpace(byte_size); } MetaspaceShared::set_shared_rs(&_rs); } else { _rs = ReservedSpace(byte_size); } MemTracker::record_virtual_memory_type((address)_rs.base(), mtClass); } // 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<mtClass> { 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); Metachunk* get_new_chunk(size_t word_size, size_t grow_chunks_by_words); 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) { Atomic::add_ptr(v, &_virtual_space_total); } size_t virtual_space_count() { return _virtual_space_count; } void inc_virtual_space_count() { Atomic::inc_ptr(&_virtual_space_count); } // 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<mtClass> { friend class Metaspace; friend class Metadebug; private: // protects allocations and contains. Mutex* const _lock; // 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; bool has_small_chunk_limit() { return !vs_list()->is_class(); } // Sum of all space in allocated chunks size_t _allocation_total; // 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; // 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; } 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; } public: SpaceManager(Mutex* lock, VirtualSpaceList* vs_list); ~SpaceManager(); enum ChunkSizes { // in words. SmallChunk = 512, MediumChunk = 8 * K, MediumChunkBunch = 4 * MediumChunk }; // Accessors size_t allocation_total() const { return _allocation_total; } void inc_allocation_total(size_t v) { Atomic::add_ptr(v, &_allocation_total); } static bool is_humongous(size_t word_size) { return word_size > MediumChunk; } static Mutex* expand_lock() { return _expand_lock; } 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); // 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_allocation_total(); #endif }; 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); // 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<Metablock, FreeList>::min_size()) { // Dark matter. Too small for dictionary. return NULL; } Metablock* free_block = dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::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(); } 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)); } // 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); // Point the chunk at the space Metachunk* result = Metachunk::initialize(chunk_limit, chunk_word_size); 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 = NULL; return take_from_committed(chunk_word_size); } 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; } // Commit only 1 page instead of the whole reserved space _rs.size() size_t committed_byte_size = os::vm_page_size(); 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, 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; } } 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); 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(); assert(succeeded, " VirtualSpaceList initialization should not fail"); link_vs(class_entry, rs.size()/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) { // Get a chunk from the chunk freelist Metachunk* next = chunk_manager()->chunk_freelist_allocate(grow_chunks_by_words); // Allocate a chunk out of the current virtual space. if (next == NULL) { 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((size_t)SpaceManager::MediumChunkBunch, 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); } if (TraceMetadataHumongousAllocation && SpaceManager::is_humongous(word_size)) { gclog_or_tty->print_cr(" aligned_expand_vs_by_words " PTR_FORMAT, aligned_expand_vs_by_words); gclog_or_tty->print_cr(" grow_vs_words " PTR_FORMAT, grow_vs_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"); } } return next; } 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 MinHeapFreeRatio and MaxHeapFreeRatio used // to resize the Java heap by some GC's. New flags can be implemented // if really needed. MinHeapFreeRatio is used to calculate how much // free space is desirable in the metaspace capacity to decide how much // to increase the HWM. MaxHeapFreeRatio 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) { // Class virtual space should always be expanded. Call GC for the other // metadata virtual space. if (vsl == Metaspace::class_space_list()) return true; // If the user wants a limit, impose one. size_t max_metaspace_size_words = MaxMetaspaceSize / BytesPerWord; size_t metaspace_size_words = MetaspaceSize / BytesPerWord; if (!FLAG_IS_DEFAULT(MaxMetaspaceSize) && vsl->capacity_words_sum() >= max_metaspace_size_words) { return false; } // 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. if (vsl->capacity_words_sum() < metaspace_size_words || capacity_until_GC() == 0) { set_capacity_until_GC(metaspace_size_words); return true; } else { if (vsl->capacity_words_sum() < capacity_until_GC()) { return true; } else { if (TraceMetadataChunkAllocation && Verbose) { gclog_or_tty->print_cr(" allocation request size " SIZE_FORMAT " capacity_until_GC " SIZE_FORMAT " capacity_words_sum " SIZE_FORMAT " used_words_sum " SIZE_FORMAT " free chunks " SIZE_FORMAT " free chunks count %d", word_size, capacity_until_GC(), vsl->capacity_words_sum(), vsl->used_words_sum(), vsl->chunk_manager()->free_chunks_total(), vsl->chunk_manager()->free_chunks_count()); } return false; } } } // Variables are in bytes void MetaspaceGC::compute_new_size() { assert(_shrink_factor <= 100, "invalid shrink factor"); uint current_shrink_factor = _shrink_factor; _shrink_factor = 0; VirtualSpaceList *vsl = Metaspace::space_list(); size_t capacity_after_gc = vsl->capacity_bytes_sum(); // Check to see if these two can be calculated without walking the CLDG size_t used_after_gc = vsl->used_bytes_sum(); size_t capacity_until_GC = vsl->capacity_bytes_sum(); size_t free_after_gc = capacity_until_GC - used_after_gc; const double minimum_free_percentage = MinHeapFreeRatio / 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) { const double free_percentage = ((double)free_after_gc) / capacity_until_GC; 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); double d_free_after_gc = free_after_gc / (double) K; gclog_or_tty->print_cr(" " " free_after_gc : %6.1fK" " used_after_gc : %6.1fK" " capacity_after_gc : %6.1fK" " metaspace HWM : %6.1fK", free_after_gc / (double) K, used_after_gc / (double) K, capacity_after_gc / (double) K, capacity_until_GC / (double) K); gclog_or_tty->print_cr(" " " free_percentage: %6.2f", free_percentage); } 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) { size_t expand_words = expand_bytes / BytesPerWord; MetaspaceGC::inc_capacity_until_GC(expand_words); } if (PrintGCDetails && Verbose) { size_t new_capacity_until_GC = MetaspaceGC::capacity_until_GC_in_bytes(); gclog_or_tty->print_cr(" expanding:" " minimum_desired_capacity: %6.1fK" " expand_words: %6.1fK" " MinMetaspaceExpansion: %6.1fK" " new metaspace HWM: %6.1fK", 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 size_t shrink_words = 0; // We would never want to shrink more than this size_t max_shrink_words = capacity_until_GC - minimum_desired_capacity; assert(max_shrink_words >= 0, err_msg("max_shrink_words " SIZE_FORMAT, max_shrink_words)); // Should shrinking be considered? if (MaxHeapFreeRatio < 100) { const double maximum_free_percentage = MaxHeapFreeRatio / 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 (PrintGC && 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(" " " capacity_until_GC: %6.1fK" " minimum_desired_capacity: %6.1fK" " maximum_desired_capacity: %6.1fK", capacity_until_GC / (double) K, 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_words = 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_words = shrink_words / 100 * current_shrink_factor; assert(shrink_words <= max_shrink_words, err_msg("invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT, shrink_words, max_shrink_words)); 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_words: %.1fK" " current_shrink_factor: %d" " new shrink factor: %d" " MinMetaspaceExpansion: %.1fK", shrink_words / (double) K, current_shrink_factor, _shrink_factor, MinMetaspaceExpansion / (double) K); } } } // Don't shrink unless it's significant if (shrink_words >= MinMetaspaceExpansion) { VirtualSpaceNode* csp = vsl->current_virtual_space(); size_t available_to_shrink = csp->capacity_words_in_vs() - csp->used_words_in_vs(); shrink_words = MIN2(shrink_words, available_to_shrink); csp->shrink_by(shrink_words); MetaspaceGC::dec_capacity_until_GC(shrink_words); if (PrintGCDetails && Verbose) { size_t new_capacity_until_GC = MetaspaceGC::capacity_until_GC_in_bytes(); gclog_or_tty->print_cr(" metaspace HWM: %.1fK", new_capacity_until_GC / (double) K); } } assert(vsl->used_bytes_sum() == used_after_gc && used_after_gc <= vsl->capacity_bytes_sum(), "sanity check"); } // 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 // ChunkList methods size_t ChunkList::sum_list_size() { size_t result = 0; Metachunk* cur = head(); while (cur != NULL) { result += cur->word_size(); cur = cur->next(); } return result; } size_t ChunkList::sum_list_count() { size_t result = 0; Metachunk* cur = head(); while (cur != NULL) { result++; cur = cur->next(); } return result; } size_t ChunkList::sum_list_capacity() { size_t result = 0; Metachunk* cur = head(); while (cur != NULL) { result += cur->capacity_word_size(); cur = cur->next(); } return result; } void ChunkList::add_at_head(Metachunk* head, Metachunk* tail) { assert_lock_strong(SpaceManager::expand_lock()); assert(tail->next() == NULL, "Not the tail"); if (TraceMetadataChunkAllocation && Verbose) { tty->print("ChunkList::add_at_head: "); Metachunk* cur = head; while (cur != NULL) { tty->print(PTR_FORMAT " (" SIZE_FORMAT ") ", cur, cur->word_size()); cur = cur->next(); } tty->print_cr(""); } if (tail != NULL) { tail->set_next(_head); } set_head(head); } void ChunkList::add_at_head(Metachunk* list) { if (list == NULL) { // Nothing to add return; } assert_lock_strong(SpaceManager::expand_lock()); Metachunk* head = list; Metachunk* tail = list; Metachunk* cur = head->next(); // Search for the tail since it is not passed. while (cur != NULL) { tail = cur; cur = cur->next(); } add_at_head(head, tail); } // ChunkManager methods // Verification of _free_chunks_total and _free_chunks_count does not // work with the CMS collector because its use of additional locks // complicate the mutex deadlock detection but it can still be useful // for detecting errors in the chunk accounting with other collectors. size_t ChunkManager::free_chunks_total() { #ifdef ASSERT if (!UseConcMarkSweepGC && !SpaceManager::expand_lock()->is_locked()) { MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); slow_locked_verify_free_chunks_total(); } #endif 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 0x%x count 0x%x", _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 0x%x count 0x%x", 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 = SmallIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { ChunkList* list = free_chunks(i); if (list == NULL) { continue; } result = result + list->sum_list_capacity(); } 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 = SmallIndex; i < NumberOfFreeLists; i = next_chunk_index(i)) { ChunkList* list = free_chunks(i); if (list == NULL) { continue; } count = count + list->sum_list_count(); } count = count + humongous_dictionary()->total_free_blocks(); return count; } ChunkList* ChunkManager::find_free_chunks_list(size_t word_size) { switch (word_size) { case SpaceManager::SmallChunk : return &_free_chunks[0]; case SpaceManager::MediumChunk : return &_free_chunks[1]; default: assert(word_size > SpaceManager::MediumChunk, "List inconsistency"); return &_free_chunks[2]; } } 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 (!SpaceManager::is_humongous(word_size)) { 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->set_head(chunk->next()); chunk->set_next(NULL); // Chunk has been 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<Metachunk>::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()); #ifdef ASSERT 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() || SpaceManager::is_humongous(chunk->word_size()), "Non-humongous variable sized chunk"); if (TraceMetadataChunkAllocation) { tty->print("ChunkManager::chunk_freelist_allocate: chunk " PTR_FORMAT " size " SIZE_FORMAT " ", chunk, chunk->word_size()); locked_print_free_chunks(tty); } return chunk; } void ChunkManager::print_on(outputStream* out) { if (PrintFLSStatistics != 0) { humongous_dictionary()->report_statistics(); } } // SpaceManager methods 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 = SmallIndex; 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 = SmallIndex; 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; size_t count = 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. if (chunk != NULL) { Metachunk* prev = chunk; while (chunk != NULL && chunk != current_chunk()) { result += chunk->free_word_size(); prev = chunk; chunk = chunk->next(); count++; } } return result; } size_t SpaceManager::sum_capacity_in_chunks_in_use() const { MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); size_t sum = 0; for (ChunkIndex i = SmallIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) { Metachunk* chunk = chunks_in_use(i); while (chunk != NULL) { // Just changed this sum += chunk->capacity_word_size(); // sum += chunk->word_size() - Metachunk::overhead(); 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 = SmallIndex; 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 = SmallIndex; 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 { Metachunk* small_chunk = chunks_in_use(SmallIndex); st->print_cr("SpaceManager: small chunk " PTR_FORMAT " free " SIZE_FORMAT, small_chunk, small_chunk->free_word_size()); Metachunk* medium_chunk = chunks_in_use(MediumIndex); st->print("medium chunk " PTR_FORMAT, medium_chunk); Metachunk* tail = current_chunk(); st->print_cr(" current chunk " PTR_FORMAT, tail); Metachunk* head = chunks_in_use(HumongousIndex); st->print_cr("humongous chunk " PTR_FORMAT, head); 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 && (!has_small_chunk_limit() || sum_count_in_chunks_in_use(SmallIndex) < _small_chunk_limit)) { chunk_word_size = (size_t) SpaceManager::SmallChunk; if (word_size + Metachunk::overhead() > SpaceManager::SmallChunk) { chunk_word_size = MediumChunk; } } else { chunk_word_size = MediumChunk; } // Might still need a humongous chunk chunk_word_size = MAX2((size_t) chunk_word_size, word_size + Metachunk::overhead()); 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) { gclog_or_tty->print_cr("SpaceManager::grow_and_allocate for " SIZE_FORMAT " words " SIZE_FORMAT " space left", word_size, current_chunk() != NULL ? current_chunk()->free_word_size() : 0); } // Get another chunk out of the virtual space size_t grow_chunks_by_words = calc_chunk_size(word_size); Metachunk* next = vs_list()->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 = SmallIndex; 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(Mutex* lock, VirtualSpaceList* vs_list) : _vs_list(vs_list), _allocation_total(0), _lock(lock) { Metadebug::init_allocation_fail_alot_count(); for (ChunkIndex i = SmallIndex; 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); } } SpaceManager::~SpaceManager() { MutexLockerEx fcl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag); ChunkManager* chunk_manager = vs_list()->chunk_manager(); chunk_manager->slow_locked_verify(); if (TraceMetadataChunkAllocation && Verbose) { gclog_or_tty->print_cr("~SpaceManager(): " PTR_FORMAT, this); locked_print_chunks_in_use_on(gclog_or_tty); } // Mangle freed memory. NOT_PRODUCT(mangle_freed_chunks();) // Have to update before the chunks_in_use lists are emptied // below. chunk_manager->inc_free_chunks_total(sum_capacity_in_chunks_in_use(), sum_count_in_chunks_in_use()); // Add all the chunks in use by this space manager // to the global list of free chunks. // Small chunks. There is one _current_chunk for each // Metaspace. It could point to a small or medium chunk. // Rather than determine which it is, follow the list of // small chunks to add them to the free list Metachunk* small_chunk = chunks_in_use(SmallIndex); chunk_manager->free_small_chunks()->add_at_head(small_chunk); set_chunks_in_use(SmallIndex, NULL); // After the small chunk are the medium chunks Metachunk* medium_chunk = chunks_in_use(MediumIndex); assert(medium_chunk == NULL || medium_chunk->word_size() == MediumChunk, "Chunk is on the wrong list"); if (medium_chunk != NULL) { Metachunk* head = medium_chunk; // If there is a medium chunk then the _current_chunk can only // point to the last medium chunk. Metachunk* tail = current_chunk(); chunk_manager->free_medium_chunks()->add_at_head(head, tail); set_chunks_in_use(MediumIndex, NULL); } // Humongous chunks // 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 Metachunk* next_humongous_chunks = humongous_chunks->next(); chunk_manager->humongous_dictionary()->return_chunk(humongous_chunks); humongous_chunks = next_humongous_chunks; } set_chunks_in_use(HumongousIndex, NULL); chunk_manager->slow_locked_verify(); } void SpaceManager::deallocate(MetaWord* p, size_t word_size) { assert_lock_strong(_lock); size_t min_size = TreeChunk<Metablock, FreeList>::min_size(); assert(word_size >= min_size, err_msg("Should not deallocate dark matter " SIZE_FORMAT, word_size)); block_freelists()->return_block(p, 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. switch (new_chunk->word_size()) { case SpaceManager::SmallChunk : if (chunks_in_use(SmallIndex) == NULL) { // First chunk to add to the list set_chunks_in_use(SmallIndex, new_chunk); } else { assert(current_chunk()->word_size() == SpaceManager::SmallChunk, err_msg( "Incorrect mix of sizes in chunk list " SIZE_FORMAT " new chunk " SIZE_FORMAT, current_chunk()->word_size(), new_chunk->word_size())); current_chunk()->set_next(new_chunk); } // Make current chunk set_current_chunk(new_chunk); break; case SpaceManager::MediumChunk : if (chunks_in_use(MediumIndex) == NULL) { // About to add the first medium chunk so teminate the // small chunk list. In general once medium chunks are // being added, we're past the need for small chunks. if (current_chunk() != NULL) { // Only a small chunk or the initial chunk could be // the current chunk if this is the first medium chunk. assert(current_chunk()->word_size() == SpaceManager::SmallChunk || chunks_in_use(SmallIndex) == NULL, err_msg("Should be a small chunk or initial chunk, current chunk " SIZE_FORMAT " new chunk " SIZE_FORMAT, current_chunk()->word_size(), new_chunk->word_size())); current_chunk()->set_next(NULL); } // First chunk to add to the list set_chunks_in_use(MediumIndex, new_chunk); } else { // As a minimum the first medium chunk added would // have become the _current_chunk // so the _current_chunk has to be non-NULL here // (although not necessarily still the first medium chunk). assert(current_chunk()->word_size() == SpaceManager::MediumChunk, "A medium chunk should the current chunk"); current_chunk()->set_next(new_chunk); } // Make current chunk set_current_chunk(new_chunk); break; default: { // 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() > MediumChunk, "List inconsistency"); } } 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); vs_list()->chunk_manager()->locked_print_free_chunks(tty); } } MetaWord* SpaceManager::allocate(size_t word_size) { MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); // 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"); 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_allocation_total(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_allocation_total(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) { // Skip the small chunks because their next link points to // medium chunks. This is because the small chunk is the // current chunk (for allocations) until it is full and the // the addition of the next chunk does not NULL the next // like of the small chunk. for (ChunkIndex i = MediumIndex; 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() == MediumChunk || chunk->word_size() == SmallChunk, "Chunk size is wrong"); return; } #ifdef ASSERT void SpaceManager::verify_allocation_total() { #if 0 // Verification is only guaranteed at a safepoint. if (SafepointSynchronize::is_at_safepoint()) { gclog_or_tty->print_cr("Chunk " PTR_FORMAT " allocation_total " SIZE_FORMAT " sum_used_in_chunks_in_use " SIZE_FORMAT, this, allocation_total(), sum_used_in_chunks_in_use()); } MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); assert(allocation_total() == sum_used_in_chunks_in_use(), err_msg("allocation total is not consistent %d vs %d", allocation_total(), sum_used_in_chunks_in_use())); #endif } #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 = SmallIndex; 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()->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 = SmallIndex; index < NumberOfInUseLists; index = next_chunk_index(index)) { for (Metachunk* curr = chunks_in_use(index); curr != NULL; curr = curr->next()) { // Try to detect incorrectly terminated small chunk // list. assert(index == MediumIndex || curr != chunks_in_use(MediumIndex), err_msg("Mangling medium chunks in small chunks? " "curr " PTR_FORMAT " medium list " PTR_FORMAT, curr, chunks_in_use(MediumIndex))); curr->mangle(); } } } #endif // PRODUCT // MetaspaceAux size_t MetaspaceAux::used_in_bytes() { return (Metaspace::class_space_list()->used_words_sum() + Metaspace::space_list()->used_words_sum()) * BytesPerWord; } size_t MetaspaceAux::used_in_bytes(Metaspace::MetadataType mdtype) { size_t used = 0; ClassLoaderDataGraphMetaspaceIterator iter; while (iter.repeat()) { Metaspace* msp = iter.get_next(); // Sum allocation_total for each metaspace if (msp != NULL) { used += msp->used_words(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; } // The total words available for metadata allocation. This // uses Metaspace capacity_words() which is the total words // in chunks allocated for a Metaspace. size_t MetaspaceAux::capacity_in_bytes() { return (Metaspace::class_space_list()->capacity_words_sum() + Metaspace::space_list()->capacity_words_sum()) * BytesPerWord; } size_t MetaspaceAux::capacity_in_bytes(Metaspace::MetadataType mdtype) { size_t capacity = free_chunks_total(mdtype); ClassLoaderDataGraphMetaspaceIterator iter; while (iter.repeat()) { Metaspace* msp = iter.get_next(); if (msp != NULL) { capacity += msp->capacity_words(mdtype); } } return capacity * BytesPerWord; } size_t MetaspaceAux::reserved_in_bytes() { return (Metaspace::class_space_list()->virtual_space_total() + Metaspace::space_list()->virtual_space_total()) * BytesPerWord; } size_t MetaspaceAux::reserved_in_bytes(Metaspace::MetadataType mdtype) { size_t reserved = (mdtype == Metaspace::ClassType) ? Metaspace::class_space_list()->virtual_space_total() : Metaspace::space_list()->virtual_space_total(); return reserved * BytesPerWord; } size_t MetaspaceAux::min_chunk_size() { return SpaceManager::MediumChunk; } size_t MetaspaceAux::free_chunks_total(Metaspace::MetadataType mdtype) { ChunkManager* chunk = (mdtype == Metaspace::ClassType) ? Metaspace::class_space_list()->chunk_manager() : Metaspace::space_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; } 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 "/" SIZE_FORMAT ")", prev_metadata_used, used_in_bytes(), capacity_in_bytes(), reserved_in_bytes()); } else { gclog_or_tty->print(" " SIZE_FORMAT "K" "->" SIZE_FORMAT "K" "(" SIZE_FORMAT "K/" SIZE_FORMAT "K)", prev_metadata_used / K, used_in_bytes()/ K, capacity_in_bytes()/K, reserved_in_bytes()/ K); } gclog_or_tty->print("]"); } // This is printed when PrintGCDetails void MetaspaceAux::print_on(outputStream* out) { Metaspace::MetadataType ct = Metaspace::ClassType; Metaspace::MetadataType nct = Metaspace::NonClassType; out->print_cr(" Metaspace total " SIZE_FORMAT "K, used " SIZE_FORMAT "K," " reserved " SIZE_FORMAT "K", capacity_in_bytes()/K, used_in_bytes()/K, reserved_in_bytes()/K); out->print_cr(" data space " SIZE_FORMAT "K, used " SIZE_FORMAT "K," " reserved " SIZE_FORMAT "K", capacity_in_bytes(nct)/K, used_in_bytes(nct)/K, reserved_in_bytes(nct)/K); out->print_cr(" class space " SIZE_FORMAT "K, used " SIZE_FORMAT "K," " reserved " SIZE_FORMAT "K", capacity_in_bytes(ct)/K, used_in_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_in_bytes(mdtype); size_t used_bytes = used_in_bytes(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); assert(used_and_free == capacity_bytes, "Accounting is wrong"); } // Print total fragmentation for class and data metaspaces separately void MetaspaceAux::print_waste(outputStream* out) { size_t small_waste = 0, medium_waste = 0, large_waste = 0; size_t cls_small_waste = 0, cls_medium_waste = 0, cls_large_waste = 0; ClassLoaderDataGraphMetaspaceIterator iter; while (iter.repeat()) { Metaspace* msp = iter.get_next(); if (msp != NULL) { small_waste += msp->vsm()->sum_waste_in_chunks_in_use(SmallIndex); medium_waste += msp->vsm()->sum_waste_in_chunks_in_use(MediumIndex); large_waste += msp->vsm()->sum_waste_in_chunks_in_use(HumongousIndex); cls_small_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(SmallIndex); cls_medium_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(MediumIndex); cls_large_waste += msp->class_vsm()->sum_waste_in_chunks_in_use(HumongousIndex); } } out->print_cr("Total fragmentation waste (words) doesn't count free space"); out->print(" data: small " SIZE_FORMAT " medium " SIZE_FORMAT, small_waste, medium_waste); out->print_cr(" class: small " SIZE_FORMAT, cls_small_waste); } // 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(); Metaspace::class_space_list()->chunk_manager()->verify(); } // Metaspace methods size_t Metaspace::_first_chunk_word_size = 0; Metaspace::Metaspace(Mutex* lock, size_t word_size) { initialize(lock, word_size); } Metaspace::Metaspace(Mutex* lock) { initialize(lock); } Metaspace::~Metaspace() { delete _vsm; delete _class_vsm; } VirtualSpaceList* Metaspace::_space_list = NULL; VirtualSpaceList* Metaspace::_class_space_list = NULL; #define VIRTUALSPACEMULTIPLIER 2 void Metaspace::global_initialize() { // Initialize the alignment for shared spaces. int max_alignment = os::vm_page_size(); 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. size_t total = align_size_up(SharedReadOnlySize + SharedReadWriteSize + SharedMiscDataSize + SharedMiscCodeSize, os::vm_allocation_granularity()); size_t word_size = total/wordSize; _space_list = new VirtualSpaceList(word_size); } 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) 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."); } } // Initialize this before initializing the VirtualSpaceList _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord; // Arbitrarily set the initial virtual space to a multiple // of the boot class loader size. size_t word_size = VIRTUALSPACEMULTIPLIER * Metaspace::first_chunk_word_size(); // Initialize the list of virtual spaces. _space_list = new VirtualSpaceList(word_size); } } // For UseCompressedKlassPointers the class space is reserved as a piece of the // Java heap because the compression algorithm is the same for each. The // argument passed in is at the top 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("%d != %d", rs.size(), ClassMetaspaceSize)); _class_space_list = new VirtualSpaceList(rs); } void Metaspace::initialize(Mutex* lock, size_t initial_size) { // Use SmallChunk size if not specified. If specified, use this size for // the data metaspace. size_t word_size; size_t class_word_size; if (initial_size == 0) { word_size = (size_t) SpaceManager::SmallChunk; class_word_size = (size_t) SpaceManager::SmallChunk; } else { word_size = initial_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. class_word_size = MIN2((size_t)SpaceManager::MediumChunk*5, (ClassMetaspaceSize/BytesPerWord)*2); } assert(space_list() != NULL, "Metadata VirtualSpaceList has not been initialized"); _vsm = new SpaceManager(lock, space_list()); if (_vsm == NULL) { return; } assert(class_space_list() != NULL, "Class VirtualSpaceList has not been initialized"); // Allocate SpaceManager for classes. _class_vsm = new SpaceManager(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()->current_virtual_space()->get_chunk_vs_with_expand(word_size); 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 Metachunk* class_chunk = class_space_list()->current_virtual_space()->get_chunk_vs_with_expand(class_word_size); if (class_chunk != NULL) { class_vsm()->add_chunk(class_chunk, true); } } MetaWord* Metaspace::allocate(size_t word_size, MetadataType mdtype) { // DumpSharedSpaces doesn't use class metadata area (yet) if (mdtype == ClassType && !DumpSharedSpaces) { 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_words = MetaspaceGC::delta_capacity_until_GC(word_size); MetaspaceGC::inc_capacity_until_GC(delta_words); 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(MetadataType mdtype) const { // return vsm()->allocation_total(); return mdtype == ClassType ? class_vsm()->sum_used_in_chunks_in_use() : vsm()->sum_used_in_chunks_in_use(); // includes overhead! } size_t Metaspace::free_words(MetadataType mdtype) const { return mdtype == ClassType ? class_vsm()->sum_free_in_chunks_in_use() : 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(MetadataType mdtype) const { return mdtype == ClassType ? class_vsm()->sum_capacity_in_chunks_in_use() : vsm()->sum_capacity_in_chunks_in_use(); } 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 MutexLocker ml(vsm()->lock()); if (word_size < TreeChunk<Metablock, FreeList>::min_size()) { // Dark matter. Too small for dictionary. #ifdef ASSERT Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5); #endif return; } if (is_class) { class_vsm()->deallocate(ptr, word_size); } else { vsm()->deallocate(ptr, word_size); } } else { MutexLocker ml(vsm()->lock()); if (word_size < TreeChunk<Metablock, FreeList>::min_size()) { // Dark matter. Too small for dictionary. #ifdef ASSERT Copy::fill_to_words((HeapWord*)ptr, word_size, 0xf5f5f5f5); #endif return; } if (is_class) { 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, MetadataType mdtype, TRAPS) { if (HAS_PENDING_EXCEPTION) { assert(false, "Should not allocate with exception pending"); return NULL; // caller does a CHECK_NULL too } // 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) { if (read_only) { result = loader_data->ro_metaspace()->allocate(word_size, NonClassType); } else { result = loader_data->rw_metaspace()->allocate(word_size, NonClassType); } if (result == NULL) { report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite); } 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) { // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support report_java_out_of_memory("Metadata space"); if (JvmtiExport::should_post_resource_exhausted()) { JvmtiExport::post_resource_exhausted( JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR, "Metadata space"); } THROW_OOP_0(Universe::out_of_memory_error_perm_gen()); } } return Metablock::initialize(result, word_size); } void Metaspace::print_on(outputStream* out) const { // Print both class virtual space counts and metaspace. if (Verbose) { vsm()->print_on(out); 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) || class_space_list()->contains(ptr); } void Metaspace::verify() { vsm()->verify(); class_vsm()->verify(); } void Metaspace::dump(outputStream* const out) const { if (UseMallocOnly) { // Just print usage for now out->print_cr("usage %d", used_words(Metaspace::NonClassType)); } out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, vsm()); vsm()->dump(out); out->print_cr("\nClass space manager: " INTPTR_FORMAT, class_vsm()); class_vsm()->dump(out); }