Transitioning from MapReduce 1 to MapReduce 2
Before upgrading your cluster to CDP Private Cloud Base, you must import the configuration settings from MapReduce version 1 (MRv1) to MapReduce version 2 (MRv2) for the cluster to benefit from the improvements in MRv2 such as the separation of cluster resource management capabilities from MapReduce-specific logic.
MapReduce 2 is an upgrade to the way that scheduling, resource management, and execution occur in Hadoop. At their core, the improvements separate cluster resource management capabilities from MapReduce-specific logic. They enable Hadoop to share resources dynamically between MapReduce and other parallel processing frameworks, such as Impala, allow more sensible and finer-grained resource configuration for better cluster utilization, and permit it to scale to accommodate more and larger jobs.
For more information about the new architecture, see Understanding YARN architecture in the Cloudera Runtime documentation.