Package org.apache.flink.runtime.checkpoint

Interface OperatorStateRepartitioner<T>

All Known Implementing Classes:
MappingBasedRepartitioner, RoundRobinOperatorStateRepartitioner
@Internal public interface OperatorStateRepartitioner<T>
Interface that allows to implement different strategies for repartitioning of operator state as parallelism changes.

  • Method Summary

    Modifier and Type
    Method
    Description
    List<List<T>>
    repartitionState(List<List<T>> previousParallelSubtaskStates, int oldParallelism, int newParallelism)
     

  • Method Details

    • repartitionState

      List<List<T>> repartitionState(List<List<T>> previousParallelSubtaskStates, int oldParallelism, int newParallelism)
      Parameters:
      previousParallelSubtaskStates - List with one entry of state handles per parallel subtask of an operator, as they have been checkpointed.
      oldParallelism - The parallelism before we start redistribution.
      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.