com.hazelcast.memory

Class ThreadLocalPoolingMemoryManager

java.lang.Object

com.hazelcast.memory.ThreadLocalPoolingMemoryManager

All Implemented Interfaces:

com.hazelcast.internal.memory.MemoryAllocator, HazelcastMemoryManager, com.hazelcast.nio.Disposable

public class ThreadLocalPoolingMemoryManager
extends Object
implements HazelcastMemoryManager

Single-threaded implementation of a pooling memory manager. To use it, a thread must register itself by calling PoolingMemoryManager.registerThread(Thread). After that, all requests from that thread will be forwarded to its own ThreadLocalPoolingMemoryManager instance. A request to free a block from a thread different than the one that allocated it will result in an exception.

Field Summary

Fields

Modifier and Type	Field and Description
protected static int	EXTERNAL_BLOCK_HEADER_SIZE
protected com.hazelcast.internal.memory.MemoryAllocator	pageAllocator

Fields inherited from interface com.hazelcast.memory.HazelcastMemoryManager

SIZE_INVALID

Fields inherited from interface com.hazelcast.internal.memory.MemoryAllocator

NULL_ADDRESS

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ThreadLocalPoolingMemoryManager(int minBlockSize, int pageSize, LibMalloc malloc, PooledNativeMemoryStats stats)

Method Summary

Modifier and Type	Method and Description
protected long	acquireInternal(com.hazelcast.memory.AddressQueue queue)
long	allocate(long size) Allocates memory from an internal memory pool or falls back to OS if not enough memory available in pool.
protected long	allocateExternalBlock(long size) Allocates a memory block directly from the page allocator.
void	compact() Compacts the memory region.
protected void	compact(com.hazelcast.memory.AddressQueue queue)
protected com.hazelcast.memory.AddressQueue	createAddressQueue(int index, int size)
void	dispose()
String	dump()
void	free(long address, long size) Gives allocated memory block back to internal pool or to OS if pool is over capacity.
protected void	freeExternalBlock(long address, long size) Frees an external block, which was allocated directly from the page allocator.
protected void	freePage(long pageAddress)
protected com.hazelcast.memory.AddressQueue	getAddressQueue(long size)
long	getAllocatedSize(long address) Returns allocated size of memory block as if it belongs to and is allocated by this memory manager.
double	getFragmentationRatio(int size)
com.hazelcast.memory.MemoryStats	getMemoryStats()
protected int	getOffsetWithinPage(long address)
protected int	getQueueMergeThreshold(com.hazelcast.memory.AddressQueue queue)
protected long	getSizeInternal(long address)
com.hazelcast.internal.memory.MemoryAllocator	getSystemAllocator()
long	getUsableSize(long address) Returns size of memory block as if it belongs to and is allocated by this memory manager.
protected int	headerSize()
protected void	initialize(long address, int size, int offset)
protected boolean	isAvailable(long address)
boolean	isDisposed() Gets the disposed state of this memory manager.
protected boolean	isValidAndAvailable(long address, int expectedSize)
protected void	markAvailable(long address)
protected boolean	markInvalid(long address, int expectedSize, int offset)
protected boolean	markUnavailable(long address, int usedSize, int internalSize)
protected com.hazelcast.internal.util.counters.Counter	newCounter()
long	newSequence() Creates a new sequence.
protected void	onMallocPage(long pageAddress)
protected void	onOome(com.hazelcast.memory.NativeOutOfMemoryError e)
long	reallocate(long address, long currentSize, long newSize)
protected long	toHeaderAddress(long blockBase, int pageOffset)
String	toString()
long	validateAndGetAllocatedSize(long address) Returns allocated size of memory block if and only if it belongs to and is allocated by this memory manager.
long	validateAndGetUsableSize(long address) Returns size of memory block if and only if it belongs to and is allocated by this memory manager.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface com.hazelcast.memory.HazelcastMemoryManager

allocate, compact, free, getAllocatedSize, getMemoryStats, getSystemAllocator, getUsableSize, newSequence, validateAndGetUsableSize

Methods inherited from interface com.hazelcast.internal.memory.MemoryAllocator

reallocate

Field Detail

EXTERNAL_BLOCK_HEADER_SIZE

protected static final int EXTERNAL_BLOCK_HEADER_SIZE

See Also:

Constant Field Values

pageAllocator

protected final com.hazelcast.internal.memory.MemoryAllocator pageAllocator

Constructor Detail

ThreadLocalPoolingMemoryManager

protected ThreadLocalPoolingMemoryManager(int minBlockSize,
                                          int pageSize,
                                          LibMalloc malloc,
                                          PooledNativeMemoryStats stats)

Method Detail

isDisposed

public boolean isDisposed()

Description copied from interface: HazelcastMemoryManager

Gets the disposed state of this memory manager.

Specified by:

isDisposed in interface HazelcastMemoryManager

Returns:

true if this memory manager is destroyed, false otherwise

dispose

public void dispose()

Specified by:

dispose in interface com.hazelcast.nio.Disposable

validateAndGetAllocatedSize

public long validateAndGetAllocatedSize(long address)

Description copied from interface: HazelcastMemoryManager

Returns allocated size of memory block if and only if it belongs to and is allocated by this memory manager. Otherwise, if memory block is not valid anymore or it is not known by this memory manager, HazelcastMemoryManager.SIZE_INVALID is returned.

Allocated size includes usable memory size plus any header or metadata region size reserved by memory manager.

Specified by:

validateAndGetAllocatedSize in interface HazelcastMemoryManager

Parameters:

address - address of memory block

Returns:

size of memory block or HazelcastMemoryManager.SIZE_INVALID if it's unknown

See Also:

HazelcastMemoryManager.validateAndGetUsableSize(long)

toString

public String toString()

Overrides:

toString in class Object

initialize

protected void initialize(long address,
                          int size,
                          int offset)

createAddressQueue

protected com.hazelcast.memory.AddressQueue createAddressQueue(int index,
                                                               int size)

headerSize

protected int headerSize()

onMallocPage

protected void onMallocPage(long pageAddress)

onOome

protected void onOome(com.hazelcast.memory.NativeOutOfMemoryError e)

allocateExternalBlock

protected long allocateExternalBlock(long size)

Allocates a memory block directly from the page allocator. Used for blocks larger than page size.

Parameters:

size - requested size of the block (the block actually allocated will be large enough to also accommodate the external block header)

Returns:

address of the block of the requested size (it is preceded by the external block header)

freeExternalBlock

protected void freeExternalBlock(long address,
                                 long size)

Frees an external block, which was allocated directly from the page allocator.

Parameters:

address - address of the block (it is directly preceded by the external block header, which is an integral part of the block actually allocated)

size - size of the block (excludes header size)

markAvailable

protected void markAvailable(long address)

markUnavailable

protected boolean markUnavailable(long address,
                                  int usedSize,
                                  int internalSize)

isAvailable

protected boolean isAvailable(long address)

markInvalid

protected boolean markInvalid(long address,
                              int expectedSize,
                              int offset)

isValidAndAvailable

protected boolean isValidAndAvailable(long address,
                                      int expectedSize)

getSizeInternal

protected long getSizeInternal(long address)

getOffsetWithinPage

protected int getOffsetWithinPage(long address)

getQueueMergeThreshold

protected int getQueueMergeThreshold(com.hazelcast.memory.AddressQueue queue)

newCounter

protected com.hazelcast.internal.util.counters.Counter newCounter()

allocate

public final long allocate(long size)

Description copied from interface: HazelcastMemoryManager

Allocates memory from an internal memory pool or falls back to OS if not enough memory available in pool. Content of the memory block will be initialized to zero.

Complement of HazelcastMemoryManager.free(long, long). Memory allocated by this method should be freed using HazelcastMemoryManager.free(long, long)

Specified by:

allocate in interface com.hazelcast.internal.memory.MemoryAllocator

Specified by:

allocate in interface HazelcastMemoryManager

Parameters:

size - of requested memory block

Returns:

address of memory block

reallocate

public long reallocate(long address,
                       long currentSize,
                       long newSize)

Specified by:

reallocate in interface com.hazelcast.internal.memory.MemoryAllocator

free

public final void free(long address,
                       long size)

Description copied from interface: HazelcastMemoryManager

Gives allocated memory block back to internal pool or to OS if pool is over capacity.

Complement of HazelcastMemoryManager.allocate(long). Only memory allocated by HazelcastMemoryManager.allocate(long) can be freed using this method.

Specified by:

free in interface com.hazelcast.internal.memory.MemoryAllocator

Specified by:

free in interface HazelcastMemoryManager

Parameters:

address - address of memory block

size - size of memory block

getMemoryStats

public final com.hazelcast.memory.MemoryStats getMemoryStats()

Specified by:

getMemoryStats in interface HazelcastMemoryManager

getSystemAllocator

public final com.hazelcast.internal.memory.MemoryAllocator getSystemAllocator()

Specified by:

getSystemAllocator in interface HazelcastMemoryManager

Returns:

the metadata memory allocator.

compact

public final void compact()

Description copied from interface: HazelcastMemoryManager

Compacts the memory region.

Specified by:

compact in interface HazelcastMemoryManager

getAllocatedSize

public final long getAllocatedSize(long address)

Description copied from interface: HazelcastMemoryManager

Returns allocated size of memory block as if it belongs to and is allocated by this memory manager. If memory block is not known by this memory manager, HazelcastMemoryManager.SIZE_INVALID is returned.

Allocated size includes usable memory size plus any header or metadata region size reserved by memory manager.

Specified by:

getAllocatedSize in interface HazelcastMemoryManager

Parameters:

address - address of memory block

Returns:

size of memory block or HazelcastMemoryManager.SIZE_INVALID if it's unknown

See Also:

HazelcastMemoryManager.getUsableSize(long)

getUsableSize

public final long getUsableSize(long address)

Description copied from interface: HazelcastMemoryManager

Returns size of memory block as if it belongs to and is allocated by this memory manager. If memory block is not known by this memory manager, HazelcastMemoryManager.SIZE_INVALID is returned.

Specified by:

getUsableSize in interface HazelcastMemoryManager

Parameters:

address - address of memory block

Returns:

size of memory block or HazelcastMemoryManager.SIZE_INVALID if it's unknown

validateAndGetUsableSize

public final long validateAndGetUsableSize(long address)

Description copied from interface: HazelcastMemoryManager

Returns size of memory block if and only if it belongs to and is allocated by this memory manager. Otherwise, if memory block is not valid anymore or it is not known by this memory manager, HazelcastMemoryManager.SIZE_INVALID is returned.

Specified by:

validateAndGetUsableSize in interface HazelcastMemoryManager

Parameters:

address - address of memory block

Returns:

size of memory block or HazelcastMemoryManager.SIZE_INVALID if it's unknown

newSequence

public final long newSequence()

Description copied from interface: HazelcastMemoryManager

Creates a new sequence. This sequence is guaranteed to be atomically incremental.

Use case for this sequence is to avoid ABA problem by using it with the address to create a "safe pointer" (address, sequence) to a memory block.

Specified by:

newSequence in interface HazelcastMemoryManager

Returns:

new sequence

getAddressQueue

protected final com.hazelcast.memory.AddressQueue getAddressQueue(long size)

acquireInternal

protected final long acquireInternal(com.hazelcast.memory.AddressQueue queue)

toHeaderAddress

protected final long toHeaderAddress(long blockBase,
                                     int pageOffset)

compact

protected final void compact(com.hazelcast.memory.AddressQueue queue)

freePage

protected final void freePage(long pageAddress)

getFragmentationRatio

public final double getFragmentationRatio(int size)

dump

public final String dump()