com.hazelcast.memory

Class StandardMemoryManager

java.lang.Object

com.hazelcast.memory.StandardMemoryManager

All Implemented Interfaces:

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

public final class StandardMemoryManager
extends Object
implements HazelcastMemoryManager, com.hazelcast.internal.metrics.MetricsProvider

Field Summary

Fields

Modifier and Type	Field and Description
static String	PROPERTY_DEBUG_ENABLED System property to enable the debug mode of StandardMemoryManager.
static String	PROPERTY_DEBUG_STACKTRACE_ENABLED System property to enable the debug mode with stacktraces of StandardMemoryManager.

Fields inherited from interface com.hazelcast.memory.HazelcastMemoryManager

SIZE_INVALID

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

NULL_ADDRESS

Constructor Summary

Constructors

Constructor and Description
StandardMemoryManager(com.hazelcast.memory.MemorySize cap)
StandardMemoryManager(com.hazelcast.memory.MemorySize cap, FreeMemoryChecker freeMemoryChecker)

Method Summary

Modifier and Type	Method and Description
long	allocate(long size) Allocates memory from an internal memory pool or falls back to OS if not enough memory available in pool.
protected static void	checkNotNull(long address, long size)
void	compact() Compacts the memory region.
void	dispose()
void	forEachAllocatedBlock(com.hazelcast.util.function.LongLongConsumer consumer)
void	free(long address, long size) Gives allocated memory block back to internal pool or to OS if pool is over capacity.
long	getAllocatedSize(long address) Returns allocated size of memory block as if it belongs to and is allocated by this memory manager.
com.hazelcast.util.collection.Long2ObjectHashMap<String>	getAllocatedStackTraces()
com.hazelcast.memory.MemoryStats	getMemoryStats()
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.
boolean	isDisposed() Gets the disposed state of this memory manager.
long	newSequence() Creates a new sequence.
void	provideMetrics(com.hazelcast.internal.metrics.MetricsRegistry registry)
long	reallocate(long address, long currentSize, long newSize)
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, toString, wait, wait, wait

Field Detail

PROPERTY_DEBUG_ENABLED

public static final String PROPERTY_DEBUG_ENABLED

System property to enable the debug mode of StandardMemoryManager.

See Also:

Constant Field Values

PROPERTY_DEBUG_STACKTRACE_ENABLED

public static final String PROPERTY_DEBUG_STACKTRACE_ENABLED

System property to enable the debug mode with stacktraces of StandardMemoryManager.

See Also:

Constant Field Values

Constructor Detail

StandardMemoryManager

public StandardMemoryManager(com.hazelcast.memory.MemorySize cap)

StandardMemoryManager

public StandardMemoryManager(com.hazelcast.memory.MemorySize cap,
                             FreeMemoryChecker freeMemoryChecker)

Method Detail

getMemoryStats

public com.hazelcast.memory.MemoryStats getMemoryStats()

Specified by:

getMemoryStats in interface HazelcastMemoryManager

allocate

public 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 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

compact

public void compact()

Description copied from interface: HazelcastMemoryManager

Compacts the memory region.

Specified by:

compact in interface HazelcastMemoryManager

getSystemAllocator

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

Specified by:

getSystemAllocator in interface HazelcastMemoryManager

Returns:

the metadata memory allocator.

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

getUsableSize

public 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 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

getAllocatedSize

public 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)

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)

newSequence

public 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

provideMetrics

public void provideMetrics(com.hazelcast.internal.metrics.MetricsRegistry registry)

Specified by:

provideMetrics in interface com.hazelcast.internal.metrics.MetricsProvider

forEachAllocatedBlock

public void forEachAllocatedBlock(com.hazelcast.util.function.LongLongConsumer consumer)

getAllocatedStackTraces

public com.hazelcast.util.collection.Long2ObjectHashMap<String> getAllocatedStackTraces()

checkNotNull

protected static void checkNotNull(long address,
                                   long size)