org.opends.server.core

Class MemoryQuota

java.lang.Object

org.opends.server.core.MemoryQuota

public class MemoryQuota
extends Object

Estimates the amount of memory in the running JVM for use of long term caches by looking at the Old Generation, where implemented, or at the Runtime information as fallback. Allows for reserving memory to avoid over commitment. There is a fudge factor involved, so it is not byte exact.

Constructor Summary

Constructors

Constructor and Description
MemoryQuota() Returns the memory quota reservation system for this server instance.

Method Summary

Modifier and Type	Method and Description
boolean	acquireMemory(long sizeInBytes) Reserves the requested amount of memory in OldGen.
long	getAvailableMemory() Returns how much memory is currently not reserved (free) in OldGen (in bytes).
long	getReservableMemory() Returns the amount of reservable memory in bytes.
boolean	isMemoryAvailable(long sizeInBytes) Check enough memory is available in the reservable pool.
int	memBytesToPercent(long sizeInBytes) Translates bytes to percent of reservable memory.
long	memPercentToBytes(int percent) Translates a percentage of reservable memory to the equivalent number of bytes.
void	releaseMemory(long sizeInBytes) Declares OldGen memory is not needed anymore.

Methods inherited from class java.lang.Object

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

Constructor Detail

MemoryQuota

public MemoryQuota()

Returns the memory quota reservation system for this server instance.

Method Detail

getReservableMemory

public long getReservableMemory()

Returns the amount of reservable memory in bytes.

Returns:

The amount of reservable memory in bytes.

isMemoryAvailable

public boolean isMemoryAvailable(long sizeInBytes)

Check enough memory is available in the reservable pool.

Parameters:

sizeInBytes - the amount of requested memory (in bytes)

Returns:

true if enough memory is available in the reservable pool

acquireMemory

public boolean acquireMemory(long sizeInBytes)

Reserves the requested amount of memory in OldGen.

Parameters:

sizeInBytes - the requested amount of memory (in bytes)

Returns:

true if the requested amount of memory in OldGen could be reserved

getAvailableMemory

public long getAvailableMemory()

Returns how much memory is currently not reserved (free) in OldGen (in bytes).

Returns:

how much memory is currently not reserved (free) in OldGen (in bytes)

memBytesToPercent

public int memBytesToPercent(long sizeInBytes)

Translates bytes to percent of reservable memory.

Parameters:

sizeInBytes - the amount of memory (in bytes)

Returns:

percent of reservable memory

memPercentToBytes

public long memPercentToBytes(int percent)

Translates a percentage of reservable memory to the equivalent number of bytes.

Parameters:

percent - a percentage of reservable memory

Returns:

the equivalent number of bytes

releaseMemory

public void releaseMemory(long sizeInBytes)

Declares OldGen memory is not needed anymore.

Parameters:

sizeInBytes - the amount of memory to return (in bytes)