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The Pentaho MapReduce job entry allows you to build MapReduce jobs using Kettle transformations as the Mapper, Combiner, and/or Reducer.

Architecture Overview

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Distributed Cache

Pentaho MapReduce relies on Hadoop's Distributed Cache to distribute the Kettle environment, configuration, and plugins across the cluster. By leveraging the Distributed Cache network traffic is reduced up for subsequent executions as the Kettle environment is automatically configured on each node. This also allows you to use multiple version of Kettle against a single cluster.

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