Introduction

Introduction

YARN can be thought of as analogous of an operating system for a cluster. A cluster is a set of loosely or tightly connected computers that work together to be viewed as a single system. The cluster represents the collection of resources, such as compute, memory, disk-space, and network bandwidth, that YARN must arbitrate among jobs that run on the cluster. Similar to how an operating system presides over the machine’s resources and distributes them among competing processes, YARN allocates cluster resources among competing jobs. The following picture shows where YARN sits in the Hadoop stack: