org.apache.flink.runtime.checkpoint

Interface OperatorStateRepartitioner

All Known Implementing Classes:

RoundRobinOperatorStateRepartitioner

public interface OperatorStateRepartitioner

Interface that allows to implement different strategies for repartitioning of operator state as parallelism changes.

Method Summary

Modifier and Type	Method and Description
List<Collection<OperatorStateHandle>>	repartitionState(List<OperatorStateHandle> previousParallelSubtaskStates, int newParallelism)

Method Detail

repartitionState

List<Collection<OperatorStateHandle>> repartitionState(List<OperatorStateHandle> previousParallelSubtaskStates,
                                                       int newParallelism)

Parameters:

previousParallelSubtaskStates - List of state handles to the parallel subtask states of an operator, as they have been checkpointed.

newParallelism - The parallelism that we consider for the state redistribution. Determines the size of the returned list.

Returns:

List with one entry per parallel subtask. Each subtask receives now one collection of states that build of the new total state for this subtask.