alluxio.client.block.policy

Class CapacityBaseRandomPolicy

java.lang.Object

alluxio.client.block.policy.CapacityBaseRandomPolicy

All Implemented Interfaces:

BlockLocationPolicy

@ThreadSafe
public class CapacityBaseRandomPolicy
extends Object
implements BlockLocationPolicy

Randomly distribute workload based on the worker capacities so bigger workers get more requests. The randomness is based on the capacity instead of availability because in the long run, all workers will be filled up and have availability close to 0. We do not want the policy to degenerate to all workers having the same chance.

Nested Class Summary

Nested classes/interfaces inherited from interface alluxio.client.block.policy.BlockLocationPolicy

BlockLocationPolicy.Factory

Constructor Summary

Constructors

Constructor and Description
CapacityBaseRandomPolicy(AlluxioConfiguration ignoredConf) Constructs a new CapacityBaseRandomPolicy needed for instantiation in BlockLocationPolicy.Factory.

Method Summary

Modifier and Type	Method and Description
Optional<WorkerNetAddress>	getWorker(GetWorkerOptions options) Gets the worker's network address for serving operations requested for the block.
protected long	randomInCapacity(long totalCapacity)

Methods inherited from class java.lang.Object

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

Constructor Detail

CapacityBaseRandomPolicy

public CapacityBaseRandomPolicy(AlluxioConfiguration ignoredConf)

Constructs a new CapacityBaseRandomPolicy needed for instantiation in BlockLocationPolicy.Factory.

Parameters:

ignoredConf - is unused

Method Detail

getWorker

public Optional<WorkerNetAddress> getWorker(GetWorkerOptions options)

Description copied from interface: BlockLocationPolicy

Gets the worker's network address for serving operations requested for the block.

Specified by:

getWorker in interface BlockLocationPolicy

Parameters:

options - the options to get a block worker network address for a block

Returns:

the address of the worker to write to, or empty if no worker can be selected

randomInCapacity

protected long randomInCapacity(long totalCapacity)