org.apache.spark.rdd

Interface PartitionCoalescer

All Known Implementing Classes:

DefaultPartitionCoalescer

public interface PartitionCoalescer

::DeveloperApi:: A PartitionCoalescer defines how to coalesce the partitions of a given RDD.

Method Summary

Modifier and Type	Method and Description
PartitionGroup[]	coalesce(int maxPartitions, RDD<?> parent) Coalesce the partitions of the given RDD.

Method Detail

coalesce

PartitionGroup[] coalesce(int maxPartitions,
                          RDD<?> parent)

Coalesce the partitions of the given RDD.

Parameters:

maxPartitions - the maximum number of partitions to have after coalescing

parent - the parent RDD whose partitions to coalesce

Returns:

an array of PartitionGroups, where each element is itself an array of Partitions and represents a partition after coalescing is performed.