Apache Hadoop™ YARN: Moving beyond MapReduce and Batch Processing with Apache Hadoop™ 2

4. Functional Overview of YARN Components

YARN relies on three main components for all of its functionality. The first component is the ResourceManager (RM), which is the arbitrator of all cluster resources. It has two parts: a pluggable scheduler and an ApplicationManager that manages user jobs on the cluster. The second component is the per-node NodeManager (NM), which manages users’ jobs and workflow on a given node. The central ResourceManager and the collection of NodeManagers create the unified computational infrastructure of the cluster. The third component is the ApplicationMaster, a user job life-cycle manager. The ApplicationMaster is where the user application resides. Together, these three components provide a very scalable, flexible, ...