Apache YARN is the processing layer for managing distributed applications that run on multiple machines in a network. YARN allows you to use various data processing engines for batch, interactive, and real-time stream processing of data.

Apache Hadoop YARN

Apache Hadoop YARN Reference

Describes how to tune and optimize YARN for your cluster. Includes information about the YARN configuration parameters and REST APIs. Also, provides information about choosing Capacity Scheduler, its benefits, and performance improvements along with comparison of features between Fair Scheduler and Capacity Scheduler.