io.ray.streaming.state.keystate

Class KeyGroupAssignment

java.lang.Object

io.ray.streaming.state.keystate.KeyGroupAssignment

public final class KeyGroupAssignment
extends Object

This class defines key-group assignment algorithm。

Constructor Summary

Constructors

Constructor and Description
KeyGroupAssignment()

Method Summary

Modifier and Type	Method and Description
static int	assignKeyGroupIndexForKey(Object key, int maxParallelism) Assigning the key to a key-group index.
static Map<Integer,List<Integer>>	computeKeyGroupToTask(int maxParallelism, List<Integer> targetTasks)
static KeyGroup	getKeyGroup(int maxParallelism, int parallelism, int index) Computes the range of key-groups that are assigned for a given operator instance.

Methods inherited from class java.lang.Object

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

Constructor Detail

KeyGroupAssignment

public KeyGroupAssignment()

Method Detail

getKeyGroup

public static KeyGroup getKeyGroup(int maxParallelism,
                                   int parallelism,
                                   int index)

Computes the range of key-groups that are assigned for a given operator instance.

Parameters:

maxParallelism - Maximal parallelism of the job.

parallelism - Parallelism for the job. <= maxParallelism.

index - index of the operator instance.

assignKeyGroupIndexForKey

public static int assignKeyGroupIndexForKey(Object key,
                                            int maxParallelism)

Assigning the key to a key-group index.

Parameters:

key - the key to assign.

maxParallelism - the maximum parallelism.

Returns:

the key-group index to which the given key is assigned.

computeKeyGroupToTask

public static Map<Integer,List<Integer>> computeKeyGroupToTask(int maxParallelism,
                                                               List<Integer> targetTasks)