Package org.apache.hadoop.ozone.container.common.volume

Class CapacityVolumeChoosingPolicy

java.lang.Object

org.apache.hadoop.ozone.container.common.volume.CapacityVolumeChoosingPolicy

All Implemented Interfaces:

VolumeChoosingPolicy

public class CapacityVolumeChoosingPolicy
extends Object
implements VolumeChoosingPolicy

Volume choosing policy that randomly choose volume with remaining space to satisfy the size constraints.

The Algorithm is as follows, Pick 2 random volumes from a given pool of volumeSet and then pick the volume with lower utilization. This leads to a higher probability of volume with lower utilization to be picked.

Same algorithm as the SCMContainerPlacementCapacity.

Constructor Summary

Constructors

Constructor	Description
CapacityVolumeChoosingPolicy()

Method Summary

Modifier and Type	Method	Description
HddsVolume	chooseVolume(List<HddsVolume> volumes, long maxContainerSize)	Choose a volume to place a container, given a list of volumes and the max container size sought for storage.

Methods inherited from class java.lang.Object

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

Constructor Details

CapacityVolumeChoosingPolicy

public CapacityVolumeChoosingPolicy()

Method Details

chooseVolume

public HddsVolume chooseVolume(List<HddsVolume> volumes,
 long maxContainerSize)
                        throws IOException

Description copied from interface: VolumeChoosingPolicy

Choose a volume to place a container, given a list of volumes and the max container size sought for storage. The implementations of this interface must be thread-safe.

Specified by:

chooseVolume in interface VolumeChoosingPolicy

Parameters:

volumes - - a list of available volumes.

maxContainerSize - - the maximum size of the container for which a volume is sought.

Returns:

the chosen volume.

Throws:

IOException - when disks are unavailable or are full.