org.apache.cassandra.utils.memory

Class Pool

java.lang.Object

org.apache.cassandra.utils.memory.Pool

Direct Known Subclasses:

HeapPool, HeapSlabPool

public abstract class Pool
extends java.lang.Object

Represents an amount of memory used for a given purpose, that can be allocated to specific tasks through child AbstractAllocator objects. AbstractAllocator and MemoryTracker correspond approximately to PoolAllocator and Pool, respectively, with the MemoryTracker bookkeeping the total shared use of resources, and the AbstractAllocator the amount checked out and in use by a specific PoolAllocator. Note the difference between acquire() and allocate(); allocate() makes more resources available to all owners, and acquire() makes shared resources unavailable but still recorded. An Owner must always acquire resources, but only needs to allocate if there are none already available. This distinction is not always meaningful.

Field Summary

Fields

Modifier and Type	Field and Description
float	cleanThreshold
long	limit

Constructor Summary

Constructors

Constructor and Description
Pool(long limit, float cleanThreshold, java.lang.Runnable cleaner)

Method Summary

Methods

Modifier and Type	Method and Description
long	allocated()
abstract PoolAllocator	newAllocator(OpOrder writes)
long	reclaiming()
long	used()

Methods inherited from class java.lang.Object

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

Field Detail

limit

public final long limit

cleanThreshold

public final float cleanThreshold

Constructor Detail

Pool

public Pool(long limit,
    float cleanThreshold,
    java.lang.Runnable cleaner)

Method Detail

allocated

public long allocated()

used

public long used()

reclaiming

public long reclaiming()

newAllocator

public abstract PoolAllocator newAllocator(OpOrder writes)