8080775: Better argument formatting for assert() and friends
Reviewed-by: kbarrett, pliden
/*
* Copyright (c) 2011, 2015, 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.
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*/
#include "precompiled.hpp"
#include "gc/shared/collectedHeap.hpp"
#include "gc/shared/collectorPolicy.hpp"
#include "gc/shared/gcLocker.hpp"
#include "memory/allocation.hpp"
#include "memory/binaryTreeDictionary.hpp"
#include "memory/filemap.hpp"
#include "memory/freeList.hpp"
#include "memory/metachunk.hpp"
#include "memory/metaspace.hpp"
#include "memory/metaspaceGCThresholdUpdater.hpp"
#include "memory/metaspaceShared.hpp"
#include "memory/metaspaceTracer.hpp"
#include "memory/resourceArea.hpp"
#include "memory/universe.hpp"
#include "runtime/atomic.inline.hpp"
#include "runtime/globals.hpp"
#include "runtime/init.hpp"
#include "runtime/java.hpp"
#include "runtime/mutex.hpp"
#include "runtime/orderAccess.inline.hpp"
#include "services/memTracker.hpp"
#include "services/memoryService.hpp"
#include "utilities/copy.hpp"
#include "utilities/debug.hpp"
#include "utilities/macros.hpp"
typedef BinaryTreeDictionary<Metablock, FreeList<Metablock> > BlockTreeDictionary;
typedef BinaryTreeDictionary<Metachunk, FreeList<Metachunk> > ChunkTreeDictionary;
// Set this constant to enable slow integrity checking of the free chunk lists
const bool metaspace_slow_verify = false;
size_t const allocation_from_dictionary_limit = 4 * K;
MetaWord* last_allocated = 0;
size_t Metaspace::_compressed_class_space_size;
const MetaspaceTracer* Metaspace::_tracer = NULL;
// 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
};
static ChunkIndex next_chunk_index(ChunkIndex i) {
assert(i < NumberOfInUseLists, "Out of bound");
return (ChunkIndex) (i+1);
}
volatile intptr_t MetaspaceGC::_capacity_until_GC = 0;
uint MetaspaceGC::_shrink_factor = 0;
bool MetaspaceGC::_should_concurrent_collect = false;
typedef class FreeList<Metachunk> ChunkList;
// Manages the global free lists of chunks.
class ChunkManager : public CHeapObj<mtInternal> {
friend class TestVirtualSpaceNodeTest;
// 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(size_t specialized_size, size_t small_size, size_t medium_size)
: _free_chunks_total(0), _free_chunks_count(0) {
_free_chunks[SpecializedIndex].set_size(specialized_size);
_free_chunks[SmallIndex].set_size(small_size);
_free_chunks[MediumIndex].set_size(medium_size);
}
// add or delete (return) a chunk to the global freelist.
Metachunk* chunk_freelist_allocate(size_t word_size);
// 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_words();
size_t free_chunks_total_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);
// Remove from a list by size. Selects list based on size of chunk.
Metachunk* free_chunks_get(size_t chunk_word_size);
#define index_bounds_check(index) \
assert(index == SpecializedIndex || \
index == SmallIndex || \
index == MediumIndex || \
index == HumongousIndex, "Bad index: %d", (int) index)
size_t num_free_chunks(ChunkIndex index) const {
index_bounds_check(index);
if (index == HumongousIndex) {
return _humongous_dictionary.total_free_blocks();
}
ssize_t count = _free_chunks[index].count();
return count == -1 ? 0 : (size_t) count;
}
size_t size_free_chunks_in_bytes(ChunkIndex index) const {
index_bounds_check(index);
size_t word_size = 0;
if (index == HumongousIndex) {
word_size = _humongous_dictionary.total_size();
} else {
const size_t size_per_chunk_in_words = _free_chunks[index].size();
word_size = size_per_chunk_in_words * num_free_chunks(index);
}
return word_size * BytesPerWord;
}
MetaspaceChunkFreeListSummary chunk_free_list_summary() const {
return MetaspaceChunkFreeListSummary(num_free_chunks(SpecializedIndex),
num_free_chunks(SmallIndex),
num_free_chunks(MediumIndex),
num_free_chunks(HumongousIndex),
size_free_chunks_in_bytes(SpecializedIndex),
size_free_chunks_in_bytes(SmallIndex),
size_free_chunks_in_bytes(MediumIndex),
size_free_chunks_in_bytes(HumongousIndex));
}
// 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) const;
};
// 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* const _dictionary;
// Only allocate and split from freelist if the size of the allocation
// is at least 1/4th the size of the available block.
const static int WasteMultiplier = 4;
// 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() { return dictionary()->total_size(); }
void print_on(outputStream* st) const;
};
// A VirtualSpaceList node.
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;
// 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(); }
// Committed but unused space in the virtual space
size_t free_words_in_vs() const;
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(); }
bool contains(const void* ptr) { return ptr >= low() && ptr < high(); }
size_t reserved_words() const { return _virtual_space.reserved_size() / BytesPerWord; }
size_t committed_words() const { return _virtual_space.actual_committed_size() / BytesPerWord; }
bool is_pre_committed() const { return _virtual_space.special(); }
// 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 word_size <= pointer_delta(end(), _top, sizeof(MetaWord)); }
MetaWord* top() const { return _top; }
void inc_top(size_t word_size) { _top += word_size; }
uintx container_count() { return _container_count; }
void inc_container_count();
void dec_container_count();
#ifdef ASSERT
uintx container_count_slow();
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;
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);
// Expands/shrinks the committed space in a virtual space. Delegates
// to Virtualspace
bool expand_by(size_t min_words, size_t preferred_words);
// In preparation for deleting this node, remove all the chunks
// in the node from any freelist.
void purge(ChunkManager* chunk_manager);
// If an allocation doesn't fit in the current node a new node is created.
// Allocate chunks out of the remaining committed space in this node
// to avoid wasting that memory.
// This always adds up because all the chunk sizes are multiples of
// the smallest chunk size.
void retire(ChunkManager* chunk_manager);
#ifdef ASSERT
// Debug support
void mangle();
#endif
void print_on(outputStream* st) const;
};
#define assert_is_ptr_aligned(ptr, alignment) \
assert(is_ptr_aligned(ptr, alignment), \
PTR_FORMAT " is not aligned to " \
SIZE_FORMAT, p2i(ptr), alignment)
#define assert_is_size_aligned(size, alignment) \
assert(is_size_aligned(size, alignment), \
SIZE_FORMAT " is not aligned to " \
SIZE_FORMAT, size, alignment)
// Decide if large pages should be committed when the memory is reserved.
static bool should_commit_large_pages_when_reserving(size_t bytes) {
if (UseLargePages && UseLargePagesInMetaspace && !os::can_commit_large_page_memory()) {
size_t words = bytes / BytesPerWord;
bool is_class = false; // We never reserve large pages for the class space.
if (MetaspaceGC::can_expand(words, is_class) &&
MetaspaceGC::allowed_expansion() >= words) {
return true;
}
}
return false;
}
// byte_size is the size of the associated virtualspace.
VirtualSpaceNode::VirtualSpaceNode(size_t bytes) : _top(NULL), _next(NULL), _rs(), _container_count(0) {
assert_is_size_aligned(bytes, Metaspace::reserve_alignment());
#if INCLUDE_CDS
// 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) {
bool large_pages = false; // No large pages when dumping the CDS archive.
char* shared_base = (char*)align_ptr_up((char*)SharedBaseAddress, Metaspace::reserve_alignment());
_rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages, shared_base);
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(bytes, Metaspace::reserve_alignment(), large_pages);
}
MetaspaceShared::set_shared_rs(&_rs);
} else
#endif
{
bool large_pages = should_commit_large_pages_when_reserving(bytes);
_rs = ReservedSpace(bytes, Metaspace::reserve_alignment(), large_pages);
}
if (_rs.is_reserved()) {
assert(_rs.base() != NULL, "Catch if we get a NULL address");
assert(_rs.size() != 0, "Catch if we get a 0 size");
assert_is_ptr_aligned(_rs.base(), Metaspace::reserve_alignment());
assert_is_size_aligned(_rs.size(), Metaspace::reserve_alignment());
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_tagged_free(), "Should be tagged 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
uintx VirtualSpaceNode::container_count_slow() {
uintx 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_tagged_free()) {
count++;
}
chunk = (Metachunk*) next;
}
return count;
}
#endif
// List of VirtualSpaces for metadata allocation.
class VirtualSpaceList : public CHeapObj<mtClass> {
friend class VirtualSpaceNode;
enum VirtualSpaceSizes {
VirtualSpaceSize = 256 * K
};
// Head of the list
VirtualSpaceNode* _virtual_space_list;
// virtual space currently being used for allocations
VirtualSpaceNode* _current_virtual_space;
// Is this VirtualSpaceList used for the compressed class space
bool _is_class;
// Sum of reserved and committed memory in the virtual spaces
size_t _reserved_words;
size_t _committed_words;
// Number of virtual spaces
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);
// 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 create_new_virtual_space(size_t vs_word_size);
// Chunk up the unused committed space in the current
// virtual space and add the chunks to the free list.
void retire_current_virtual_space();
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);
bool expand_node_by(VirtualSpaceNode* node,
size_t min_words,
size_t preferred_words);
bool expand_by(size_t min_words,
size_t preferred_words);
VirtualSpaceNode* current_virtual_space() {
return _current_virtual_space;
}
bool is_class() const { return _is_class; }
bool initialization_succeeded() { return _virtual_space_list != NULL; }
size_t reserved_words() { return _reserved_words; }
size_t reserved_bytes() { return reserved_words() * BytesPerWord; }
size_t committed_words() { return _committed_words; }
size_t committed_bytes() { return committed_words() * BytesPerWord; }
void inc_reserved_words(size_t v);
void dec_reserved_words(size_t v);
void inc_committed_words(size_t v);
void dec_committed_words(size_t v);
void inc_virtual_space_count();
void dec_virtual_space_count();
bool contains(const void* ptr);
// Unlink empty VirtualSpaceNodes and free it.
void purge(ChunkManager* chunk_manager);
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 _allocation_fail_alot_count;
public:
static void init_allocation_fail_alot_count();
#ifdef ASSERT
static bool test_metadata_failure();
#endif
};
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
Mutex* const _lock;
// Type of metadata allocated.
Metaspace::MetadataType _mdtype;
// 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;
// Maximum number of small chunks to allocate to a SpaceManager
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 Metaspace::get_space_list(_mdtype); }
ChunkManager* chunk_manager() const { return Metaspace::get_chunk_manager(_mdtype); }
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);
void retire_current_chunk();
Mutex* lock() const { return _lock; }
const char* chunk_size_name(ChunkIndex index) const;
protected:
void initialize();
public:
SpaceManager(Metaspace::MetadataType mdtype,
Mutex* lock);
~SpaceManager();
enum ChunkMultiples {
MediumChunkMultiple = 4
};
bool is_class() { return _mdtype == Metaspace::ClassType; }
// Accessors
size_t specialized_chunk_size() { return (size_t) is_class() ? ClassSpecializedChunk : SpecializedChunk; }
size_t small_chunk_size() { return (size_t) is_class() ? ClassSmallChunk : SmallChunk; }
size_t medium_chunk_size() { return (size_t) is_class() ? ClassMediumChunk : MediumChunk; }
size_t medium_chunk_bunch() { return medium_chunk_size() * MediumChunkMultiple; }
size_t smallest_chunk_size() { return specialized_chunk_size(); }
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_bytes() const { return _allocated_chunks_words * BytesPerWord; }
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);
// Allocates a block from a small chunk
MetaWord* get_small_chunk_and_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);
// Notify memory usage to MemoryService.
void track_metaspace_memory_usage();
// 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) {
size_t byte_size = word_size * BytesPerWord;
size_t raw_bytes_size = MAX2(byte_size, sizeof(Metablock));
raw_bytes_size = align_size_up(raw_bytes_size, Metachunk::object_alignment());
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,
Monitor::_safepoint_check_never);
void VirtualSpaceNode::inc_container_count() {
assert_lock_strong(SpaceManager::expand_lock());
_container_count++;
DEBUG_ONLY(verify_container_count();)
}
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(),
"Inconsistency in container_count _container_count " UINTX_FORMAT
" container_count_slow() " UINTX_FORMAT, _container_count, container_count_slow());
}
#endif
// BlockFreelist methods
BlockFreelist::BlockFreelist() : _dictionary(new BlockTreeDictionary()) {}
BlockFreelist::~BlockFreelist() {
if (Verbose && TraceMetadataChunkAllocation) {
dictionary()->print_free_lists(gclog_or_tty);
}
delete _dictionary;
}
void BlockFreelist::return_block(MetaWord* p, size_t word_size) {
Metablock* free_chunk = ::new (p) Metablock(word_size);
dictionary()->return_chunk(free_chunk);
}
MetaWord* BlockFreelist::get_block(size_t word_size) {
if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
// Dark matter. Too small for dictionary.
return NULL;
}
Metablock* free_block =
dictionary()->get_chunk(word_size, FreeBlockDictionary<Metablock>::atLeast);
if (free_block == NULL) {
return NULL;
}
const size_t block_size = free_block->size();
if (block_size > WasteMultiplier * word_size) {
return_block((MetaWord*)free_block, block_size);
return NULL;
}
MetaWord* new_block = (MetaWord*)free_block;
assert(block_size >= word_size, "Incorrect size of block from freelist");
const size_t unused = block_size - word_size;
if (unused >= TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
return_block(new_block + word_size, unused);
}
return new_block;
}
void BlockFreelist::print_on(outputStream* st) const {
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");
// The virtual spaces are always expanded by the
// commit granularity to enforce the following condition.
// Without this the is_available check will not work correctly.
assert(_virtual_space.committed_size() == _virtual_space.actual_committed_size(),
"The committed memory doesn't match the expanded memory.");
if (!is_available(chunk_word_size)) {
if (TraceMetadataChunkAllocation) {
gclog_or_tty->print("VirtualSpaceNode::take_from_committed() not available " SIZE_FORMAT " words ", chunk_word_size);
// Dump some information about the virtual space that is nearly full
print_on(gclog_or_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 min_words, size_t preferred_words) {
size_t min_bytes = min_words * BytesPerWord;
size_t preferred_bytes = preferred_words * BytesPerWord;
size_t uncommitted = virtual_space()->reserved_size() - virtual_space()->actual_committed_size();
if (uncommitted < min_bytes) {
return false;
}
size_t commit = MIN2(preferred_bytes, uncommitted);
bool result = virtual_space()->expand_by(commit, false);
assert(result, "Failed to commit memory");
return result;
}
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;
}
bool VirtualSpaceNode::initialize() {
if (!_rs.is_reserved()) {
return false;
}
// These are necessary restriction to make sure that the virtual space always
// grows in steps of Metaspace::commit_alignment(). If both base and size are
// aligned only the middle alignment of the VirtualSpace is used.
assert_is_ptr_aligned(_rs.base(), Metaspace::commit_alignment());
assert_is_size_aligned(_rs.size(), Metaspace::commit_alignment());
// ReservedSpaces marked as special will have the entire memory
// pre-committed. Setting a committed size will make sure that
// committed_size and actual_committed_size agrees.
size_t pre_committed_size = _rs.special() ? _rs.size() : 0;
bool result = virtual_space()->initialize_with_granularity(_rs, pre_committed_size,
Metaspace::commit_alignment());
if (result) {
assert(virtual_space()->committed_size() == virtual_space()->actual_committed_size(),
"Checking that the pre-committed memory was registered by the VirtualSpace");
set_top((MetaWord*)virtual_space()->low());
set_reserved(MemRegion((HeapWord*)_rs.base(),
(HeapWord*)(_rs.base() + _rs.size())));
assert(reserved()->start() == (HeapWord*) _rs.base(),
"Reserved start was not set properly " PTR_FORMAT
" != " PTR_FORMAT, p2i(reserved()->start()), p2i(_rs.base()));
assert(reserved()->word_size() == _rs.size() / BytesPerWord,
"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, " SIZE_FORMAT_W(3) "%% used "
"[" PTR_FORMAT ", " PTR_FORMAT ", "
PTR_FORMAT ", " PTR_FORMAT ")",
p2i(vs), capacity / K,
capacity == 0 ? 0 : used * 100 / capacity,
p2i(bottom()), p2i(top()), p2i(end()),
p2i(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_reserved_words(size_t v) {
assert_lock_strong(SpaceManager::expand_lock());
_reserved_words = _reserved_words + v;
}
void VirtualSpaceList::dec_reserved_words(size_t v) {
assert_lock_strong(SpaceManager::expand_lock());
_reserved_words = _reserved_words - v;
}
#define assert_committed_below_limit() \
assert(MetaspaceAux::committed_bytes() <= MaxMetaspaceSize, \
"Too much committed memory. Committed: " SIZE_FORMAT \
" limit (MaxMetaspaceSize): " SIZE_FORMAT, \
MetaspaceAux::committed_bytes(), MaxMetaspaceSize);
void VirtualSpaceList::inc_committed_words(size_t v) {
assert_lock_strong(SpaceManager::expand_lock());
_committed_words = _committed_words + v;
assert_committed_below_limit();
}
void VirtualSpaceList::dec_committed_words(size_t v) {
assert_lock_strong(SpaceManager::expand_lock());
_committed_words = _committed_words - v;
assert_committed_below_limit();
}
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->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(ChunkManager* chunk_manager) {
assert(SafepointSynchronize::is_at_safepoint(), "must be called at safepoint for contains to work");
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 node being the first node.
assert(vsl == virtual_space_list(), "Expected to be the first node");
set_virtual_space_list(vsl->next());
} else {
prev_vsl->set_next(vsl->next());
}
vsl->purge(chunk_manager);
dec_reserved_words(vsl->reserved_words());
dec_committed_words(vsl->committed_words());
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
}
// This function looks at the mmap regions in the metaspace without locking.
// The chunks are added with store ordering and not deleted except for at
// unloading time during a safepoint.
bool VirtualSpaceList::contains(const void* ptr) {
// List should be stable enough to use an iterator here because removing virtual
// space nodes is only allowed at a safepoint.
VirtualSpaceListIterator iter(virtual_space_list());
while (iter.repeat()) {
VirtualSpaceNode* vsn = iter.get_next();
if (vsn->contains(ptr)) {
return true;
}
}
return false;
}
void VirtualSpaceList::retire_current_virtual_space() {
assert_lock_strong(SpaceManager::expand_lock());
VirtualSpaceNode* vsn = current_virtual_space();
ChunkManager* cm = is_class() ? Metaspace::chunk_manager_class() :
Metaspace::chunk_manager_metadata();
vsn->retire(cm);
}
void VirtualSpaceNode::retire(ChunkManager* chunk_manager) {
for (int i = (int)MediumIndex; i >= (int)ZeroIndex; --i) {
ChunkIndex index = (ChunkIndex)i;
size_t chunk_size = chunk_manager->free_chunks(index)->size();
while (free_words_in_vs() >= chunk_size) {
DEBUG_ONLY(verify_container_count();)
Metachunk* chunk = get_chunk_vs(chunk_size);
assert(chunk != NULL, "allocation should have been successful");
chunk_manager->return_chunks(index, chunk);
chunk_manager->inc_free_chunks_total(chunk_size);
DEBUG_ONLY(verify_container_count();)
}
}
assert(free_words_in_vs() == 0, "should be empty now");
}
VirtualSpaceList::VirtualSpaceList(size_t word_size) :
_is_class(false),
_virtual_space_list(NULL),
_current_virtual_space(NULL),
_reserved_words(0),
_committed_words(0),
_virtual_space_count(0) {
MutexLockerEx cl(SpaceManager::expand_lock(),
Mutex::_no_safepoint_check_flag);
create_new_virtual_space(word_size);
}
VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) :
_is_class(true),
_virtual_space_list(NULL),
_current_virtual_space(NULL),
_reserved_words(0),
_committed_words(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();
if (succeeded) {
link_vs(class_entry);
}
}
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::create_new_virtual_space(size_t vs_word_size) {
assert_lock_strong(SpaceManager::expand_lock());
if (is_class()) {
assert(false, "We currently don't support more than one VirtualSpace for"
" the compressed class space. The initialization of the"
" CCS uses another code path and should not hit this path.");
return false;
}
if (vs_word_size == 0) {
assert(false, "vs_word_size should always be at least _reserve_alignment large.");
return false;
}
// Reserve the space
size_t vs_byte_size = vs_word_size * BytesPerWord;
assert_is_size_aligned(vs_byte_size, Metaspace::reserve_alignment());
// 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 {
assert(new_entry->reserved_words() == vs_word_size,
"Reserved memory size differs from requested memory size");
// ensure lock-free iteration sees fully initialized node
OrderAccess::storestore();
link_vs(new_entry);
return true;
}
}
void VirtualSpaceList::link_vs(VirtualSpaceNode* new_entry) {
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_reserved_words(new_entry->reserved_words());
inc_committed_words(new_entry->committed_words());
inc_virtual_space_count();
#ifdef ASSERT
new_entry->mangle();
#endif
if (TraceMetavirtualspaceAllocation && Verbose) {
VirtualSpaceNode* vsl = current_virtual_space();
vsl->print_on(gclog_or_tty);
}
}
bool VirtualSpaceList::expand_node_by(VirtualSpaceNode* node,
size_t min_words,
size_t preferred_words) {
size_t before = node->committed_words();
bool result = node->expand_by(min_words, preferred_words);
size_t after = node->committed_words();
// after and before can be the same if the memory was pre-committed.
assert(after >= before, "Inconsistency");
inc_committed_words(after - before);
return result;
}
bool VirtualSpaceList::expand_by(size_t min_words, size_t preferred_words) {
assert_is_size_aligned(min_words, Metaspace::commit_alignment_words());
assert_is_size_aligned(preferred_words, Metaspace::commit_alignment_words());
assert(min_words <= preferred_words, "Invalid arguments");
if (!MetaspaceGC::can_expand(min_words, this->is_class())) {
return false;
}
size_t allowed_expansion_words = MetaspaceGC::allowed_expansion();
if (allowed_expansion_words < min_words) {
return false;
}
size_t max_expansion_words = MIN2(preferred_words, allowed_expansion_words);
// Commit more memory from the the current virtual space.
bool vs_expanded = expand_node_by(current_virtual_space(),
min_words,
max_expansion_words);
if (vs_expanded) {
return true;
}
retire_current_virtual_space();
// Get another virtual space.
size_t grow_vs_words = MAX2((size_t)VirtualSpaceSize, preferred_words);
grow_vs_words = align_size_up(grow_vs_words, Metaspace::reserve_alignment_words());
if (create_new_virtual_space(grow_vs_words)) {
if (current_virtual_space()->is_pre_committed()) {
// The memory was pre-committed, so we are done here.
assert(min_words <= current_virtual_space()->committed_words(),
"The new VirtualSpace was pre-committed, so it"
"should be large enough to fit the alloc request.");
return true;
}
return expand_node_by(current_virtual_space(),
min_words,
max_expansion_words);
}
return false;
}
Metachunk* VirtualSpaceList::get_new_chunk(size_t word_size,
size_t grow_chunks_by_words,
size_t medium_chunk_bunch) {
// Allocate a chunk out of the current virtual space.
Metachunk* next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
if (next != NULL) {
return next;
}
// The expand amount is currently only determined by the requested sizes
// and not how much committed memory is left in the current virtual space.
size_t min_word_size = align_size_up(grow_chunks_by_words, Metaspace::commit_alignment_words());
size_t preferred_word_size = align_size_up(medium_chunk_bunch, Metaspace::commit_alignment_words());
if (min_word_size >= preferred_word_size) {
// Can happen when humongous chunks are allocated.
preferred_word_size = min_word_size;
}
bool expanded = expand_by(min_word_size, preferred_word_size);
if (expanded) {
next = current_virtual_space()->get_chunk_vs(grow_chunks_by_words);
assert(next != NULL, "The allocation was expected to succeed after the expansion");
}
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);
}
}
}
// 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, increase by MaxMetaspaceExpansion.
// If that is still not enough, expand by the size of the allocation
// plus some.
size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) {
size_t min_delta = MinMetaspaceExpansion;
size_t max_delta = MaxMetaspaceExpansion;
size_t delta = align_size_up(bytes, Metaspace::commit_alignment());
if (delta <= min_delta) {
delta = min_delta;
} else if (delta <= max_delta) {
// 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 = max_delta;
} else {
// This allocation is large but the next ones are probably not
// so increase by the minimum.
delta = delta + min_delta;
}
assert_is_size_aligned(delta, Metaspace::commit_alignment());
return delta;
}
size_t MetaspaceGC::capacity_until_GC() {
size_t value = (size_t)OrderAccess::load_ptr_acquire(&_capacity_until_GC);
assert(value >= MetaspaceSize, "Not initialized properly?");
return value;
}
bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC) {
assert_is_size_aligned(v, Metaspace::commit_alignment());
size_t capacity_until_GC = (size_t) _capacity_until_GC;
size_t new_value = capacity_until_GC + v;
if (new_value < capacity_until_GC) {
// The addition wrapped around, set new_value to aligned max value.
new_value = align_size_down(max_uintx, Metaspace::commit_alignment());
}
intptr_t expected = (intptr_t) capacity_until_GC;
intptr_t actual = Atomic::cmpxchg_ptr((intptr_t) new_value, &_capacity_until_GC, expected);
if (expected != actual) {
return false;
}
if (new_cap_until_GC != NULL) {
*new_cap_until_GC = new_value;
}
if (old_cap_until_GC != NULL) {
*old_cap_until_GC = capacity_until_GC;
}
return true;
}
size_t MetaspaceGC::dec_capacity_until_GC(size_t v) {
assert_is_size_aligned(v, Metaspace::commit_alignment());
return (size_t)Atomic::add_ptr(-(intptr_t)v, &_capacity_until_GC);
}
void MetaspaceGC::initialize() {
// Set the high-water mark to MaxMetapaceSize during VM initializaton since
// we can't do a GC during initialization.
_capacity_until_GC = MaxMetaspaceSize;
}
void MetaspaceGC::post_initialize() {
// Reset the high-water mark once the VM initialization is done.
_capacity_until_GC = MAX2(MetaspaceAux::committed_bytes(), MetaspaceSize);
}
bool MetaspaceGC::can_expand(size_t word_size, bool is_class) {
// Check if the compressed class space is full.
if (is_class && Metaspace::using_class_space()) {
size_t class_committed = MetaspaceAux::committed_bytes(Metaspace::ClassType);
if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) {
return false;
}
}
// Check if the user has imposed a limit on the metaspace memory.
size_t committed_bytes = MetaspaceAux::committed_bytes();
if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) {
return false;
}
return true;
}
size_t MetaspaceGC::allowed_expansion() {
size_t committed_bytes = MetaspaceAux::committed_bytes();
size_t capacity_until_gc = capacity_until_GC();
assert(capacity_until_gc >= committed_bytes,
"capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT,
capacity_until_gc, committed_bytes);
size_t left_until_max = MaxMetaspaceSize - committed_bytes;
size_t left_until_GC = capacity_until_gc - committed_bytes;
size_t left_to_commit = MIN2(left_until_GC, left_until_max);
return left_to_commit / BytesPerWord;
}
void MetaspaceGC::compute_new_size() {
assert(_shrink_factor <= 100, "invalid shrink factor");
uint current_shrink_factor = _shrink_factor;
_shrink_factor = 0;
// Using committed_bytes() for used_after_gc is an overestimation, since the
// chunk free lists are included in committed_bytes() and the memory in an
// un-fragmented chunk free list is available for future allocations.
// However, if the chunk free lists becomes fragmented, then the memory may
// not be available for future allocations and the memory is therefore "in use".
// Including the chunk free lists in the definition of "in use" is therefore
// necessary. Not including the chunk free lists can cause capacity_until_GC to
// shrink below committed_bytes() and this has caused serious bugs in the past.
const size_t used_after_gc = MetaspaceAux::committed_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;
expand_bytes = align_size_up(expand_bytes, Metaspace::commit_alignment());
// Don't expand unless it's significant
if (expand_bytes >= MinMetaspaceExpansion) {
size_t new_capacity_until_GC = 0;
bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC);
assert(succeeded, "Should always succesfully increment HWM when at safepoint");
Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
new_capacity_until_GC,
MetaspaceGCThresholdUpdater::ComputeNewSize);
if (PrintGCDetails && Verbose) {
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
assert(capacity_until_GC >= minimum_desired_capacity,
SIZE_FORMAT " >= " SIZE_FORMAT,
capacity_until_GC, minimum_desired_capacity);
size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity;
// 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;
shrink_bytes = align_size_down(shrink_bytes, Metaspace::commit_alignment());
assert(shrink_bytes <= max_shrink_bytes,
"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)) {
size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes);
Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
new_capacity_until_GC,
MetaspaceGCThresholdUpdater::ComputeNewSize);
}
}
// Metadebug methods
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_words() {
return _free_chunks_total;
}
size_t ChunkManager::free_chunks_total_bytes() {
return free_chunks_total_words() * 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,
"_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,
"_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);
}
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();
if (chunk == NULL) {
return NULL;
}
// Remove the chunk as the head of the list.
free_list->remove_chunk(chunk);
if (TraceMetadataChunkAllocation && Verbose) {
gclog_or_tty->print_cr("ChunkManager::free_chunks_get: free_list "
PTR_FORMAT " head " PTR_FORMAT " size " SIZE_FORMAT,
p2i(free_list), p2i(chunk), chunk->word_size());
}
} else {
chunk = humongous_dictionary()->get_chunk(
word_size,
FreeBlockDictionary<Metachunk>::atLeast);
if (chunk == NULL) {
return NULL;
}
if (TraceMetadataHumongousAllocation) {
size_t waste = chunk->word_size() - word_size;
gclog_or_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->word_size());
// 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_tagged_free(false);
#endif
chunk->container()->inc_container_count();
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();
}
gclog_or_tty->print("ChunkManager::chunk_freelist_allocate: " PTR_FORMAT " chunk "
PTR_FORMAT " size " SIZE_FORMAT " count " SIZE_FORMAT " ",
p2i(this), p2i(chunk), chunk->word_size(), list_count);
locked_print_free_chunks(gclog_or_tty);
}
return chunk;
}
void ChunkManager::print_on(outputStream* out) const {
if (PrintFLSStatistics != 0) {
const_cast<ChunkManager *>(this)->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,
"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->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), p2i(chunk));
if (chunk != NULL) {
st->print_cr(" free " SIZE_FORMAT,
chunk->free_word_size());
} else {
st->cr();
}
}
chunk_manager()->locked_print_free_chunks(st);
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.
// After that a medium chunk is preferred.
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
// humongous allocations sizes to be aligned up to
// the smallest chunk size.
size_t if_humongous_sized_chunk =
align_size_up(word_size + Metachunk::overhead(),
smallest_chunk_size());
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,
"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;
}
void SpaceManager::track_metaspace_memory_usage() {
if (is_init_completed()) {
if (is_class()) {
MemoryService::track_compressed_class_memory_usage();
}
MemoryService::track_metaspace_memory_usage();
}
}
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
size_t grow_chunks_by_words = calc_chunk_size(word_size);
Metachunk* next = get_new_chunk(word_size, grow_chunks_by_words);
MetaWord* mem = NULL;
// If a chunk was available, add it to the in-use chunk list
// and do an allocation from it.
if (next != NULL) {
// Add to this manager's list of chunks in use.
add_chunk(next, false);
mem = next->allocate(word_size);
}
// Track metaspace memory usage statistic.
track_metaspace_memory_usage();
return mem;
}
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 " SIZE_FORMAT,
p2i(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) :
_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, p2i(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();
DEBUG_ONLY(cur->set_is_tagged_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(),
"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);
chunk_manager()->slow_locked_verify();
dec_total_from_size_metrics();
if (TraceMetadataChunkAllocation && Verbose) {
gclog_or_tty->print_cr("~SpaceManager(): " PTR_FORMAT, p2i(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 " SIZE_FORMAT " %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 " SSIZE_FORMAT " %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 " SIZE_FORMAT " %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_tagged_free(true);
#endif
if (TraceMetadataChunkAllocation && Verbose) {
gclog_or_tty->print(PTR_FORMAT " (" SIZE_FORMAT ") ",
p2i(humongous_chunks),
humongous_chunks->word_size());
}
assert(humongous_chunks->word_size() == (size_t)
align_size_up(humongous_chunks->word_size(),
smallest_chunk_size()),
"Humongous chunk size is wrong: word size " SIZE_FORMAT
" granularity " SIZE_FORMAT,
humongous_chunks->word_size(), smallest_chunk_size());
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->cr();
gclog_or_tty->print_cr("updated dictionary count " SIZE_FORMAT " %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<Metablock, FreeList<Metablock> >::min_size();
assert(raw_word_size >= min_size,
"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) {
retire_current_chunk();
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: " SIZE_FORMAT ") ",
sum_count_in_chunks_in_use());
new_chunk->print_on(gclog_or_tty);
chunk_manager()->locked_print_free_chunks(gclog_or_tty);
}
}
void SpaceManager::retire_current_chunk() {
if (current_chunk() != NULL) {
size_t remaining_words = current_chunk()->free_word_size();
if (remaining_words >= TreeChunk<Metablock, FreeList<Metablock> >::min_size()) {
block_freelists()->return_block(current_chunk()->allocate(remaining_words), remaining_words);
inc_used_metrics(remaining_words);
}
}
}
Metachunk* SpaceManager::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);
if (next == NULL) {
next = vs_list()->get_new_chunk(word_size,
grow_chunks_by_words,
medium_chunk_bunch());
}
if (TraceMetadataHumongousAllocation && next != NULL &&
SpaceManager::is_humongous(next->word_size())) {
gclog_or_tty->print_cr(" new humongous chunk word size "
PTR_FORMAT, next->word_size());
}
return next;
}
/*
* The policy is to allocate up to _small_chunk_limit small chunks
* after which only medium chunks are allocated. This is done to
* reduce fragmentation. In some cases, this can result in a lot
* of small chunks being allocated to the point where it's not
* possible to expand. If this happens, there may be no medium chunks
* available and OOME would be thrown. Instead of doing that,
* if the allocation request size fits in a small chunk, an attempt
* will be made to allocate a small chunk.
*/
MetaWord* SpaceManager::get_small_chunk_and_allocate(size_t word_size) {
size_t raw_word_size = get_raw_word_size(word_size);
if (raw_word_size + Metachunk::overhead() > small_chunk_size()) {
return NULL;
}
MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
MutexLockerEx cl1(expand_lock(), Mutex::_no_safepoint_check_flag);
Metachunk* chunk = chunk_manager()->chunk_freelist_allocate(small_chunk_size());
MetaWord* mem = NULL;
if (chunk != NULL) {
// Add chunk to the in-use chunk list and do an allocation from it.
// Add to this manager's list of chunks in use.
add_chunk(chunk, false);
mem = chunk->allocate(raw_word_size);
inc_used_metrics(raw_word_size);
// Track metaspace memory usage statistic.
track_metaspace_memory_usage();
}
return mem;
}
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);
}
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 != NULL) {
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
// verification 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(),
"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);
curr_total += curr->word_size();
used += curr->used_word_size();
capacity += curr->word_size();
waste += curr->free_word_size() + curr->overhead();;
}
}
if (TraceMetadataChunkAllocation && Verbose) {
block_freelists()->print_on(out);
}
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::_capacity_words[] = {0, 0};
size_t MetaspaceAux::_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 <= capacity_words(mdtype),
"About to decrement below 0: words " SIZE_FORMAT
" is greater than _capacity_words[%u] " SIZE_FORMAT,
words, mdtype, capacity_words(mdtype));
_capacity_words[mdtype] -= words;
}
void MetaspaceAux::inc_capacity(Metaspace::MetadataType mdtype, size_t words) {
assert_lock_strong(SpaceManager::expand_lock());
// Needs to be atomic
_capacity_words[mdtype] += words;
}
void MetaspaceAux::dec_used(Metaspace::MetadataType mdtype, size_t words) {
assert(words <= used_words(mdtype),
"About to decrement below 0: words " SIZE_FORMAT
" is greater than _used_words[%u] " SIZE_FORMAT,
words, mdtype, 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, &_used_words[mdtype]);
}
void MetaspaceAux::inc_used(Metaspace::MetadataType mdtype, size_t words) {
// _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, &_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_bytes_slow(Metaspace::MetadataType mdtype) {
size_t free = 0;
ClassLoaderDataGraphMetaspaceIterator iter;
while (iter.repeat()) {
Metaspace* msp = iter.get_next();
if (msp != NULL) {
free += msp->free_words_slow(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::capacity_bytes_slow() {
#ifdef PRODUCT
// Use capacity_bytes() in PRODUCT instead of this function.
guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT");
#endif
size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType);
size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType);
assert(capacity_bytes() == class_capacity + non_class_capacity,
"bad accounting: capacity_bytes() " SIZE_FORMAT
" class_capacity + non_class_capacity " SIZE_FORMAT
" class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT,
capacity_bytes(), class_capacity + non_class_capacity,
class_capacity, non_class_capacity);
return class_capacity + non_class_capacity;
}
size_t MetaspaceAux::reserved_bytes(Metaspace::MetadataType mdtype) {
VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
return list == NULL ? 0 : list->reserved_bytes();
}
size_t MetaspaceAux::committed_bytes(Metaspace::MetadataType mdtype) {
VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
return list == NULL ? 0 : list->committed_bytes();
}
size_t MetaspaceAux::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); }
size_t MetaspaceAux::free_chunks_total_words(Metaspace::MetadataType mdtype) {
ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype);
if (chunk_manager == NULL) {
return 0;
}
chunk_manager->slow_verify();
return chunk_manager->free_chunks_total_words();
}
size_t MetaspaceAux::free_chunks_total_bytes(Metaspace::MetadataType mdtype) {
return free_chunks_total_words(mdtype) * BytesPerWord;
}
size_t MetaspaceAux::free_chunks_total_words() {
return free_chunks_total_words(Metaspace::ClassType) +
free_chunks_total_words(Metaspace::NonClassType);
}
size_t MetaspaceAux::free_chunks_total_bytes() {
return free_chunks_total_words() * BytesPerWord;
}
bool MetaspaceAux::has_chunk_free_list(Metaspace::MetadataType mdtype) {
return Metaspace::get_chunk_manager(mdtype) != NULL;
}
MetaspaceChunkFreeListSummary MetaspaceAux::chunk_free_list_summary(Metaspace::MetadataType mdtype) {
if (!has_chunk_free_list(mdtype)) {
return MetaspaceChunkFreeListSummary();
}
const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype);
return cm->chunk_free_list_summary();
}
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,
used_bytes(),
reserved_bytes());
} else {
gclog_or_tty->print(" " SIZE_FORMAT "K"
"->" SIZE_FORMAT "K"
"(" SIZE_FORMAT "K)",
prev_metadata_used/K,
used_bytes()/K,
reserved_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 "
"used " SIZE_FORMAT "K, "
"capacity " SIZE_FORMAT "K, "
"committed " SIZE_FORMAT "K, "
"reserved " SIZE_FORMAT "K",
used_bytes()/K,
capacity_bytes()/K,
committed_bytes()/K,
reserved_bytes()/K);
if (Metaspace::using_class_space()) {
Metaspace::MetadataType ct = Metaspace::ClassType;
out->print_cr(" class space "
"used " SIZE_FORMAT "K, "
"capacity " SIZE_FORMAT "K, "
"committed " SIZE_FORMAT "K, "
"reserved " SIZE_FORMAT "K",
used_bytes(ct)/K,
capacity_bytes(ct)/K,
committed_bytes(ct)/K,
reserved_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_bytes(mdtype);
size_t capacity_bytes = capacity_bytes_slow(mdtype);
size_t used_bytes = used_bytes_slow(mdtype);
size_t free_bytes = free_bytes_slow(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::chunk_manager_metadata()->verify();
if (Metaspace::using_class_space()) {
Metaspace::chunk_manager_class()->verify();
}
}
void MetaspaceAux::verify_capacity() {
#ifdef ASSERT
size_t running_sum_capacity_bytes = 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,
"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(capacity_bytes(i) == capacity_in_use_bytes,
"capacity_bytes(%u) " SIZE_FORMAT
" capacity_bytes_slow(%u)" SIZE_FORMAT,
i, capacity_bytes(i), i, capacity_in_use_bytes);
}
#endif
}
void MetaspaceAux::verify_used() {
#ifdef ASSERT
size_t running_sum_used_bytes = used_bytes();
// For purposes of the running sum of used, verify against used
size_t used_in_use_bytes = used_bytes_slow();
assert(used_bytes() == used_in_use_bytes,
"used_bytes() " SIZE_FORMAT
" used_bytes_slow()" SIZE_FORMAT,
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(used_bytes(i) == used_in_use_bytes,
"used_bytes(%u) " SIZE_FORMAT
" used_bytes_slow(%u)" SIZE_FORMAT,
i, 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;
size_t Metaspace::_commit_alignment = 0;
size_t Metaspace::_reserve_alignment = 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;
ChunkManager* Metaspace::_chunk_manager_metadata = NULL;
ChunkManager* Metaspace::_chunk_manager_class = NULL;
#define VIRTUALSPACEMULTIPLIER 2
#ifdef _LP64
static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
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 INCLUDE_CDS
if (UseSharedSpaces) {
higher_address = MAX2((address)(cds_base + FileMapInfo::shared_spaces_size()),
(address)(metaspace_base + compressed_class_space_size()));
lower_base = MIN2(metaspace_base, cds_base);
} else
#endif
{
higher_address = metaspace_base + compressed_class_space_size();
lower_base = metaspace_base;
uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes;
// If compressed class space fits in lower 32G, we don't need a base.
if (higher_address <= (address)klass_encoding_max) {
lower_base = 0; // Effectively lower base is zero.
}
}
Universe::set_narrow_klass_base(lower_base);
if ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) {
Universe::set_narrow_klass_shift(0);
} else {
assert(!UseSharedSpaces, "Cannot shift with UseSharedSpaces");
Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes);
}
}
#if INCLUDE_CDS
// 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(UseCompressedClassPointers, "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 + compressed_class_space_size()));
return ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax);
}
#endif
// 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(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
assert(compressed_class_space_size() < KlassEncodingMetaspaceMax,
"Metaspace size is too big");
assert_is_ptr_aligned(requested_addr, _reserve_alignment);
assert_is_ptr_aligned(cds_base, _reserve_alignment);
assert_is_size_aligned(compressed_class_space_size(), _reserve_alignment);
// Don't use large pages for the class space.
bool large_pages = false;
#ifndef AARCH64
ReservedSpace metaspace_rs = ReservedSpace(compressed_class_space_size(),
_reserve_alignment,
large_pages,
requested_addr);
#else // AARCH64
ReservedSpace metaspace_rs;
// Our compressed klass pointers may fit nicely into the lower 32
// bits.
if ((uint64_t)requested_addr + compressed_class_space_size() < 4*G) {
metaspace_rs = ReservedSpace(compressed_class_space_size(),
_reserve_alignment,
large_pages,
requested_addr);
}
if (! metaspace_rs.is_reserved()) {
// Try to align metaspace so that we can decode a compressed klass
// with a single MOVK instruction. We can do this iff the
// compressed class base is a multiple of 4G.
for (char *a = (char*)align_ptr_up(requested_addr, 4*G);
a < (char*)(1024*G);
a += 4*G) {
#if INCLUDE_CDS
if (UseSharedSpaces
&& ! can_use_cds_with_metaspace_addr(a, cds_base)) {
// We failed to find an aligned base that will reach. Fall
// back to using our requested addr.
metaspace_rs = ReservedSpace(compressed_class_space_size(),
_reserve_alignment,
large_pages,
requested_addr);
break;
}
#endif
metaspace_rs = ReservedSpace(compressed_class_space_size(),
_reserve_alignment,
large_pages,
a);
if (metaspace_rs.is_reserved())
break;
}
}
#endif // AARCH64
if (!metaspace_rs.is_reserved()) {
#if INCLUDE_CDS
if (UseSharedSpaces) {
size_t increment = align_size_up(1*G, _reserve_alignment);
// 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 + increment > addr) &&
can_use_cds_with_metaspace_addr(addr + increment, cds_base)) {
addr = addr + increment;
metaspace_rs = ReservedSpace(compressed_class_space_size(),
_reserve_alignment, large_pages, addr);
}
}
#endif
// 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 UseCompressedClassPointers is off because too much
// initialization has happened that depends on UseCompressedClassPointers.
// So, UseCompressedClassPointers cannot be turned off at this point.
if (!metaspace_rs.is_reserved()) {
metaspace_rs = ReservedSpace(compressed_class_space_size(),
_reserve_alignment, large_pages);
if (!metaspace_rs.is_reserved()) {
vm_exit_during_initialization(err_msg("Could not allocate metaspace: " SIZE_FORMAT " bytes",
compressed_class_space_size()));
}
}
}
// If we got here then the metaspace got allocated.
MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass);
#if INCLUDE_CDS
// 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");
}
#endif
set_narrow_klass_base_and_shift((address)metaspace_rs.base(),
UseSharedSpaces ? (address)cds_base : 0);
initialize_class_space(metaspace_rs);
if (PrintCompressedOopsMode || (PrintMiscellaneous && Verbose)) {
print_compressed_class_space(gclog_or_tty, requested_addr);
}
}
void Metaspace::print_compressed_class_space(outputStream* st, const char* requested_addr) {
st->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: %d",
p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift());
if (_class_space_list != NULL) {
address base = (address)_class_space_list->current_virtual_space()->bottom();
st->print("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT,
compressed_class_space_size(), p2i(base));
if (requested_addr != 0) {
st->print(" Req Addr: " PTR_FORMAT, p2i(requested_addr));
}
st->cr();
}
}
// For UseCompressedClassPointers 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() >= CompressedClassSpaceSize,
SIZE_FORMAT " != " SIZE_FORMAT, rs.size(), CompressedClassSpaceSize);
assert(using_class_space(), "Must be using class space");
_class_space_list = new VirtualSpaceList(rs);
_chunk_manager_class = new ChunkManager(SpecializedChunk, ClassSmallChunk, ClassMediumChunk);
if (!_class_space_list->initialization_succeeded()) {
vm_exit_during_initialization("Failed to setup compressed class space virtual space list.");
}
}
#endif
void Metaspace::ergo_initialize() {
if (DumpSharedSpaces) {
// Using large pages when dumping the shared archive is currently not implemented.
FLAG_SET_ERGO(bool, UseLargePagesInMetaspace, false);
}
size_t page_size = os::vm_page_size();
if (UseLargePages && UseLargePagesInMetaspace) {
page_size = os::large_page_size();
}
_commit_alignment = page_size;
_reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity());
// Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will
// override if MaxMetaspaceSize was set on the command line or not.
// This information is needed later to conform to the specification of the
// java.lang.management.MemoryUsage API.
//
// Ideally, we would be able to set the default value of MaxMetaspaceSize in
// globals.hpp to the aligned value, but this is not possible, since the
// alignment depends on other flags being parsed.
MaxMetaspaceSize = align_size_down_bounded(MaxMetaspaceSize, _reserve_alignment);
if (MetaspaceSize > MaxMetaspaceSize) {
MetaspaceSize = MaxMetaspaceSize;
}
MetaspaceSize = align_size_down_bounded(MetaspaceSize, _commit_alignment);
assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize");
if (MetaspaceSize < 256*K) {
vm_exit_during_initialization("Too small initial Metaspace size");
}
MinMetaspaceExpansion = align_size_down_bounded(MinMetaspaceExpansion, _commit_alignment);
MaxMetaspaceExpansion = align_size_down_bounded(MaxMetaspaceExpansion, _commit_alignment);
CompressedClassSpaceSize = align_size_down_bounded(CompressedClassSpaceSize, _reserve_alignment);
set_compressed_class_space_size(CompressedClassSpaceSize);
}
void Metaspace::global_initialize() {
MetaspaceGC::initialize();
// Initialize the alignment for shared spaces.
int max_alignment = os::vm_allocation_granularity();
size_t cds_total = 0;
MetaspaceShared::set_max_alignment(max_alignment);
if (DumpSharedSpaces) {
#if INCLUDE_CDS
MetaspaceShared::estimate_regions_size();
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);
// make sure SharedReadOnlySize and SharedReadWriteSize are not less than
// the minimum values.
if (SharedReadOnlySize < MetaspaceShared::min_ro_size){
report_out_of_shared_space(SharedReadOnly);
}
if (SharedReadWriteSize < MetaspaceShared::min_rw_size){
report_out_of_shared_space(SharedReadWrite);
}
// the min_misc_data_size and min_misc_code_size estimates are based on
// MetaspaceShared::generate_vtable_methods().
// The minimum size only accounts for the vtable methods. Any size less than the
// minimum required size would cause vm crash when allocating the vtable methods.
uint min_misc_data_size = align_size_up(
MetaspaceShared::num_virtuals * MetaspaceShared::vtbl_list_size * sizeof(void*), max_alignment);
if (SharedMiscDataSize < min_misc_data_size) {
report_out_of_shared_space(SharedMiscData);
}
uintx min_misc_code_size = align_size_up(
(MetaspaceShared::num_virtuals * MetaspaceShared::vtbl_list_size) *
(sizeof(void*) + MetaspaceShared::vtbl_method_size) + MetaspaceShared::vtbl_common_code_size,
max_alignment);
if (SharedMiscCodeSize < min_misc_code_size) {
report_out_of_shared_space(SharedMiscCode);
}
// 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();
cds_total = align_size_up(cds_total, _reserve_alignment);
_space_list = new VirtualSpaceList(cds_total/wordSize);
_chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk);
if (!_space_list->initialization_succeeded()) {
vm_exit_during_initialization("Unable to dump shared archive.", NULL);
}
#ifdef _LP64
if (cds_total + compressed_class_space_size() > UnscaledClassSpaceMax) {
vm_exit_during_initialization("Unable to dump shared archive.",
err_msg("Size of archive (" SIZE_FORMAT ") + compressed class space ("
SIZE_FORMAT ") == total (" SIZE_FORMAT ") is larger than compressed "
"klass limit: " UINT64_FORMAT, cds_total, compressed_class_space_size(),
cds_total + compressed_class_space_size(), UnscaledClassSpaceMax));
}
// Set the compressed klass pointer base so that decoding of these pointers works
// properly when creating the shared archive.
assert(UseCompressedOops && UseCompressedClassPointers,
"UseCompressedOops and UseCompressedClassPointers 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,
p2i(_space_list->current_virtual_space()->bottom()));
}
Universe::set_narrow_klass_shift(0);
#endif // _LP64
#endif // INCLUDE_CDS
} 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) {
#if INCLUDE_CDS
FileMapInfo* mapinfo = new 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)) {
cds_total = FileMapInfo::shared_spaces_size();
cds_address = (address)mapinfo->header()->region_addr(0);
#ifdef _LP64
if (using_class_space()) {
char* cds_end = (char*)(cds_address + cds_total);
cds_end = (char *)align_ptr_up(cds_end, _reserve_alignment);
// If UseCompressedClassPointers is set then allocate the metaspace area
// above the heap and above the CDS area (if it exists).
allocate_metaspace_compressed_klass_ptrs(cds_end, cds_address);
// Map the shared string space after compressed pointers
// because it relies on compressed class pointers setting to work
mapinfo->map_string_regions();
}
#endif // _LP64
} else {
assert(!mapinfo->is_open() && !UseSharedSpaces,
"archive file not closed or shared spaces not disabled.");
}
#endif // INCLUDE_CDS
}
#ifdef _LP64
if (!UseSharedSpaces && using_class_space()) {
char* base = (char*)align_ptr_up(Universe::heap()->reserved_region().end(), _reserve_alignment);
allocate_metaspace_compressed_klass_ptrs(base, 0);
}
#endif // _LP64
// 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,
(CompressedClassSpaceSize/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;
word_size = align_size_up(word_size, Metaspace::reserve_alignment_words());
// Initialize the list of virtual spaces.
_space_list = new VirtualSpaceList(word_size);
_chunk_manager_metadata = new ChunkManager(SpecializedChunk, SmallChunk, MediumChunk);
if (!_space_list->initialization_succeeded()) {
vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL);
}
}
_tracer = new MetaspaceTracer();
}
void Metaspace::post_initialize() {
MetaspaceGC::post_initialize();
}
Metachunk* Metaspace::get_initialization_chunk(MetadataType mdtype,
size_t chunk_word_size,
size_t chunk_bunch) {
// Get a chunk from the chunk freelist
Metachunk* chunk = get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size);
if (chunk != NULL) {
return chunk;
}
return get_space_list(mdtype)->get_new_chunk(chunk_word_size, chunk_word_size, chunk_bunch);
}
void Metaspace::initialize(Mutex* lock, MetaspaceType type) {
assert(space_list() != NULL,
"Metadata VirtualSpaceList has not been initialized");
assert(chunk_manager_metadata() != NULL,
"Metadata ChunkManager has not been initialized");
_vsm = new SpaceManager(NonClassType, lock);
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");
assert(chunk_manager_class() != NULL,
"Class ChunkManager has not been initialized");
// Allocate SpaceManager for classes.
_class_vsm = new SpaceManager(ClassType, lock);
if (_class_vsm == NULL) {
return;
}
}
MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
// Allocate chunk for metadata objects
Metachunk* new_chunk = get_initialization_chunk(NonClassType,
word_size,
vsm()->medium_chunk_bunch());
// For dumping shared archive, report error if allocation has failed.
if (DumpSharedSpaces && new_chunk == NULL) {
report_insufficient_metaspace(MetaspaceAux::committed_bytes() + word_size * BytesPerWord);
}
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 = get_initialization_chunk(ClassType,
class_word_size,
class_vsm()->medium_chunk_bunch());
if (class_chunk != NULL) {
class_vsm()->add_chunk(class_chunk, true);
} else {
// For dumping shared archive, report error if allocation has failed.
if (DumpSharedSpaces) {
report_insufficient_metaspace(MetaspaceAux::committed_bytes() + class_word_size * BytesPerWord);
}
}
}
_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 UseCompressedClassPointers is true.
if (is_class_space_allocation(mdtype)) {
return class_vsm()->allocate(word_size);
} else {
return vsm()->allocate(word_size);
}
}
MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype) {
size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord);
assert(delta_bytes > 0, "Must be");
size_t before = 0;
size_t after = 0;
MetaWord* res;
bool incremented;
// Each thread increments the HWM at most once. Even if the thread fails to increment
// the HWM, an allocation is still attempted. This is because another thread must then
// have incremented the HWM and therefore the allocation might still succeed.
do {
incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before);
res = allocate(word_size, mdtype);
} while (!incremented && res == NULL);
if (incremented) {
tracer()->report_gc_threshold(before, after,
MetaspaceGCThresholdUpdater::ExpandAndAllocate);
if (PrintGCDetails && Verbose) {
gclog_or_tty->print_cr("Increase capacity to GC from " SIZE_FORMAT
" to " SIZE_FORMAT, before, after);
}
}
return res;
}
// 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_slow(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;
}
size_t Metaspace::allocated_blocks_bytes() const {
return vsm()->allocated_blocks_bytes() +
(using_class_space() ? class_vsm()->allocated_blocks_bytes() : 0);
}
size_t Metaspace::allocated_chunks_bytes() const {
return vsm()->allocated_chunks_bytes() +
(using_class_space() ? class_vsm()->allocated_chunks_bytes() : 0);
}
void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
assert(!SafepointSynchronize::is_at_safepoint()
|| Thread::current()->is_VM_thread(), "should be the VM thread");
if (DumpSharedSpaces && PrintSharedSpaces) {
record_deallocation(ptr, vsm()->get_raw_word_size(word_size));
}
MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag);
if (word_size < TreeChunk<Metablock, FreeList<Metablock> >::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);
}
}
MetaWord* 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
}
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();
MetaWord* result = space->allocate(word_size, NonClassType);
if (result == NULL) {
report_out_of_shared_space(read_only ? SharedReadOnly : SharedReadWrite);
}
if (PrintSharedSpaces) {
space->record_allocation(result, type, space->vsm()->get_raw_word_size(word_size));
}
// Zero initialize.
Copy::fill_to_aligned_words((HeapWord*)result, word_size, 0);
return result;
}
MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType;
// Try to allocate metadata.
MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype);
if (result == NULL) {
tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype);
// Allocation failed.
if (is_init_completed()) {
// Only start a GC if the bootstrapping has completed.
// Try to clean out some memory and retry.
result = Universe::heap()->collector_policy()->satisfy_failed_metadata_allocation(
loader_data, word_size, mdtype);
}
}
if (result == NULL) {
SpaceManager* sm;
if (is_class_space_allocation(mdtype)) {
sm = loader_data->metaspace_non_null()->class_vsm();
} else {
sm = loader_data->metaspace_non_null()->vsm();
}
result = sm->get_small_chunk_and_allocate(word_size);
if (result == NULL) {
report_metadata_oome(loader_data, word_size, type, mdtype, CHECK_NULL);
}
}
// Zero initialize.
Copy::fill_to_aligned_words((HeapWord*)result, word_size, 0);
return result;
}
size_t Metaspace::class_chunk_size(size_t word_size) {
assert(using_class_space(), "Has to use class space");
return class_vsm()->calc_chunk_size(word_size);
}
void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) {
tracer()->report_metadata_oom(loader_data, word_size, type, mdtype);
// If result is still null, we are out of memory.
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);
}
bool out_of_compressed_class_space = false;
if (is_class_space_allocation(mdtype)) {
Metaspace* metaspace = loader_data->metaspace_non_null();
out_of_compressed_class_space =
MetaspaceAux::committed_bytes(Metaspace::ClassType) +
(metaspace->class_chunk_size(word_size) * BytesPerWord) >
CompressedClassSpaceSize;
}
// -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
const char* space_string = out_of_compressed_class_space ?
"Compressed class space" : "Metaspace";
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 (!is_init_completed()) {
vm_exit_during_initialization("OutOfMemoryError", space_string);
}
if (out_of_compressed_class_space) {
THROW_OOP(Universe::out_of_memory_error_class_metaspace());
} else {
THROW_OOP(Universe::out_of_memory_error_metaspace());
}
}
const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) {
switch (mdtype) {
case Metaspace::ClassType: return "Class";
case Metaspace::NonClassType: return "Metadata";
default:
assert(false, "Got bad mdtype: %d", (int) mdtype);
return NULL;
}
}
void Metaspace::record_allocation(void* ptr, MetaspaceObj::Type type, size_t word_size) {
assert(DumpSharedSpaces, "sanity");
int byte_size = (int)word_size * HeapWordSize;
AllocRecord *rec = new AllocRecord((address)ptr, type, byte_size);
if (_alloc_record_head == NULL) {
_alloc_record_head = _alloc_record_tail = rec;
} else if (_alloc_record_tail->_ptr + _alloc_record_tail->_byte_size == (address)ptr) {
_alloc_record_tail->_next = rec;
_alloc_record_tail = rec;
} else {
// slow linear search, but this doesn't happen that often, and only when dumping
for (AllocRecord *old = _alloc_record_head; old; old = old->_next) {
if (old->_ptr == ptr) {
assert(old->_type == MetaspaceObj::DeallocatedType, "sanity");
int remain_bytes = old->_byte_size - byte_size;
assert(remain_bytes >= 0, "sanity");
old->_type = type;
if (remain_bytes == 0) {
delete(rec);
} else {
address remain_ptr = address(ptr) + byte_size;
rec->_ptr = remain_ptr;
rec->_byte_size = remain_bytes;
rec->_type = MetaspaceObj::DeallocatedType;
rec->_next = old->_next;
old->_byte_size = byte_size;
old->_next = rec;
}
return;
}
}
assert(0, "reallocating a freed pointer that was not recorded");
}
}
void Metaspace::record_deallocation(void* ptr, size_t word_size) {
assert(DumpSharedSpaces, "sanity");
for (AllocRecord *rec = _alloc_record_head; rec; rec = rec->_next) {
if (rec->_ptr == ptr) {
assert(rec->_byte_size == (int)word_size * HeapWordSize, "sanity");
rec->_type = MetaspaceObj::DeallocatedType;
return;
}
}
assert(0, "deallocating a pointer that was not recorded");
}
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(MetadataType mdtype) {
get_space_list(mdtype)->purge(get_chunk_manager(mdtype));
}
void Metaspace::purge() {
MutexLockerEx cl(SpaceManager::expand_lock(),
Mutex::_no_safepoint_check_flag);
purge(NonClassType);
if (using_class_space()) {
purge(ClassType);
}
}
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 (UseSharedSpaces && MetaspaceShared::is_in_shared_space(ptr)) {
return true;
}
if (using_class_space() && get_space_list(ClassType)->contains(ptr)) {
return true;
}
return get_space_list(NonClassType)->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, p2i(vsm()));
vsm()->dump(out);
if (using_class_space()) {
out->print_cr("\nClass space manager: " INTPTR_FORMAT, p2i(class_vsm()));
class_vsm()->dump(out);
}
}
/////////////// Unit tests ///////////////
#ifndef PRODUCT
class TestMetaspaceAuxTest : AllStatic {
public:
static void test_reserved() {
size_t reserved = MetaspaceAux::reserved_bytes();
assert(reserved > 0, "assert");
size_t committed = MetaspaceAux::committed_bytes();
assert(committed <= reserved, "assert");
size_t reserved_metadata = MetaspaceAux::reserved_bytes(Metaspace::NonClassType);
assert(reserved_metadata > 0, "assert");
assert(reserved_metadata <= reserved, "assert");
if (UseCompressedClassPointers) {
size_t reserved_class = MetaspaceAux::reserved_bytes(Metaspace::ClassType);
assert(reserved_class > 0, "assert");
assert(reserved_class < reserved, "assert");
}
}
static void test_committed() {
size_t committed = MetaspaceAux::committed_bytes();
assert(committed > 0, "assert");
size_t reserved = MetaspaceAux::reserved_bytes();
assert(committed <= reserved, "assert");
size_t committed_metadata = MetaspaceAux::committed_bytes(Metaspace::NonClassType);
assert(committed_metadata > 0, "assert");
assert(committed_metadata <= committed, "assert");
if (UseCompressedClassPointers) {
size_t committed_class = MetaspaceAux::committed_bytes(Metaspace::ClassType);
assert(committed_class > 0, "assert");
assert(committed_class < committed, "assert");
}
}
static void test_virtual_space_list_large_chunk() {
VirtualSpaceList* vs_list = new VirtualSpaceList(os::vm_allocation_granularity());
MutexLockerEx cl(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
// A size larger than VirtualSpaceSize (256k) and add one page to make it _not_ be
// vm_allocation_granularity aligned on Windows.
size_t large_size = (size_t)(2*256*K + (os::vm_page_size()/BytesPerWord));
large_size += (os::vm_page_size()/BytesPerWord);
vs_list->get_new_chunk(large_size, large_size, 0);
}
static void test() {
test_reserved();
test_committed();
test_virtual_space_list_large_chunk();
}
};
void TestMetaspaceAux_test() {
TestMetaspaceAuxTest::test();
}
class TestVirtualSpaceNodeTest {
static void chunk_up(size_t words_left, size_t& num_medium_chunks,
size_t& num_small_chunks,
size_t& num_specialized_chunks) {
num_medium_chunks = words_left / MediumChunk;
words_left = words_left % MediumChunk;
num_small_chunks = words_left / SmallChunk;
words_left = words_left % SmallChunk;
// how many specialized chunks can we get?
num_specialized_chunks = words_left / SpecializedChunk;
assert(words_left % SpecializedChunk == 0, "should be nothing left");
}
public:
static void test() {
MutexLockerEx ml(SpaceManager::expand_lock(), Mutex::_no_safepoint_check_flag);
const size_t vsn_test_size_words = MediumChunk * 4;
const size_t vsn_test_size_bytes = vsn_test_size_words * BytesPerWord;
// The chunk sizes must be multiples of eachother, or this will fail
STATIC_ASSERT(MediumChunk % SmallChunk == 0);
STATIC_ASSERT(SmallChunk % SpecializedChunk == 0);
{ // No committed memory in VSN
ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
VirtualSpaceNode vsn(vsn_test_size_bytes);
vsn.initialize();
vsn.retire(&cm);
assert(cm.sum_free_chunks_count() == 0, "did not commit any memory in the VSN");
}
{ // All of VSN is committed, half is used by chunks
ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
VirtualSpaceNode vsn(vsn_test_size_bytes);
vsn.initialize();
vsn.expand_by(vsn_test_size_words, vsn_test_size_words);
vsn.get_chunk_vs(MediumChunk);
vsn.get_chunk_vs(MediumChunk);
vsn.retire(&cm);
assert(cm.sum_free_chunks_count() == 2, "should have been memory left for 2 medium chunks");
assert(cm.sum_free_chunks() == 2*MediumChunk, "sizes should add up");
}
const size_t page_chunks = 4 * (size_t)os::vm_page_size() / BytesPerWord;
// This doesn't work for systems with vm_page_size >= 16K.
if (page_chunks < MediumChunk) {
// 4 pages of VSN is committed, some is used by chunks
ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
VirtualSpaceNode vsn(vsn_test_size_bytes);
vsn.initialize();
vsn.expand_by(page_chunks, page_chunks);
vsn.get_chunk_vs(SmallChunk);
vsn.get_chunk_vs(SpecializedChunk);
vsn.retire(&cm);
// committed - used = words left to retire
const size_t words_left = page_chunks - SmallChunk - SpecializedChunk;
size_t num_medium_chunks, num_small_chunks, num_spec_chunks;
chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks);
assert(num_medium_chunks == 0, "should not get any medium chunks");
assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks");
assert(cm.sum_free_chunks() == words_left, "sizes should add up");
}
{ // Half of VSN is committed, a humongous chunk is used
ChunkManager cm(SpecializedChunk, SmallChunk, MediumChunk);
VirtualSpaceNode vsn(vsn_test_size_bytes);
vsn.initialize();
vsn.expand_by(MediumChunk * 2, MediumChunk * 2);
vsn.get_chunk_vs(MediumChunk + SpecializedChunk); // Humongous chunks will be aligned up to MediumChunk + SpecializedChunk
vsn.retire(&cm);
const size_t words_left = MediumChunk * 2 - (MediumChunk + SpecializedChunk);
size_t num_medium_chunks, num_small_chunks, num_spec_chunks;
chunk_up(words_left, num_medium_chunks, num_small_chunks, num_spec_chunks);
assert(num_medium_chunks == 0, "should not get any medium chunks");
assert(cm.sum_free_chunks_count() == (num_small_chunks + num_spec_chunks), "should be space for 3 chunks");
assert(cm.sum_free_chunks() == words_left, "sizes should add up");
}
}
#define assert_is_available_positive(word_size) \
assert(vsn.is_available(word_size), \
#word_size ": " PTR_FORMAT " bytes were not available in " \
"VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \
(uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end()));
#define assert_is_available_negative(word_size) \
assert(!vsn.is_available(word_size), \
#word_size ": " PTR_FORMAT " bytes should not be available in " \
"VirtualSpaceNode [" PTR_FORMAT ", " PTR_FORMAT ")", \
(uintptr_t)(word_size * BytesPerWord), p2i(vsn.bottom()), p2i(vsn.end()));
static void test_is_available_positive() {
// Reserve some memory.
VirtualSpaceNode vsn(os::vm_allocation_granularity());
assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
// Commit some memory.
size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
assert(expanded, "Failed to commit");
// Check that is_available accepts the committed size.
assert_is_available_positive(commit_word_size);
// Check that is_available accepts half the committed size.
size_t expand_word_size = commit_word_size / 2;
assert_is_available_positive(expand_word_size);
}
static void test_is_available_negative() {
// Reserve some memory.
VirtualSpaceNode vsn(os::vm_allocation_granularity());
assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
// Commit some memory.
size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
assert(expanded, "Failed to commit");
// Check that is_available doesn't accept a too large size.
size_t two_times_commit_word_size = commit_word_size * 2;
assert_is_available_negative(two_times_commit_word_size);
}
static void test_is_available_overflow() {
// Reserve some memory.
VirtualSpaceNode vsn(os::vm_allocation_granularity());
assert(vsn.initialize(), "Failed to setup VirtualSpaceNode");
// Commit some memory.
size_t commit_word_size = os::vm_allocation_granularity() / BytesPerWord;
bool expanded = vsn.expand_by(commit_word_size, commit_word_size);
assert(expanded, "Failed to commit");
// Calculate a size that will overflow the virtual space size.
void* virtual_space_max = (void*)(uintptr_t)-1;
size_t bottom_to_max = pointer_delta(virtual_space_max, vsn.bottom(), 1);
size_t overflow_size = bottom_to_max + BytesPerWord;
size_t overflow_word_size = overflow_size / BytesPerWord;
// Check that is_available can handle the overflow.
assert_is_available_negative(overflow_word_size);
}
static void test_is_available() {
TestVirtualSpaceNodeTest::test_is_available_positive();
TestVirtualSpaceNodeTest::test_is_available_negative();
TestVirtualSpaceNodeTest::test_is_available_overflow();
}
};
void TestVirtualSpaceNode_test() {
TestVirtualSpaceNodeTest::test();
TestVirtualSpaceNodeTest::test_is_available();
}
#endif