Book Image

Learning YARN

Book Image

Learning YARN

Overview of this book

Today enterprises generate huge volumes of data. In order to provide effective services and to make smarter and more intelligent decisions from these huge volumes of data, enterprises use big-data analytics. In recent years, Hadoop has been used for massive data storage and efficient distributed processing of data. The Yet Another Resource Negotiator (YARN) framework solves the design problems related to resource management faced by the Hadoop 1.x framework by providing a more scalable, efficient, flexible, and highly available resource management framework for distributed data processing. This book starts with an overview of the YARN features and explains how YARN provides a business solution for growing big data needs. You will learn to provision and manage single, as well as multi-node, Hadoop-YARN clusters in the easiest way. You will walk through the YARN administration, life cycle management, application execution, REST APIs, schedulers, security framework and so on. You will gain insights about the YARN components and features such as ResourceManager, NodeManager, ApplicationMaster, Container, Timeline Server, High Availability, Resource Localisation and so on. The book explains Hadoop-YARN commands and the configurations of components and explores topics such as High Availability, Resource Localization and Log aggregation. You will then be ready to develop your own ApplicationMaster and execute it over a Hadoop-YARN cluster. Towards the end of the book, you will learn about the security architecture and integration of YARN with big data technologies like Spark and Storm. This book promises conceptual as well as practical knowledge of resource management using YARN.
Table of Contents (20 chapters)
Learning YARN
Credits
About the Authors
Acknowledgments
About the Reviewers
www.PacktPub.com
Preface
Index

An introduction to state management analogy


Life cycle is an important phenomenon in event-driven implementation of components in any system. Components of the system pass through a predefined series of valid states. The transition across states is governed by events associated with the state and actions to be performed to address the event occurred.

Here are the some key terms that are used in this chapter:

  • State: In computer science, the state of a computer program is a technical term for all the stored information, at a given instance in time, to which the program has access.

  • Event: An event is an action or occurrence detected by the program that may be handled by the program. Typically, events are handled synchronously with the program flow, that is, the program has one or more dedicated places where events are handled.

  • Event handle: Handles are associated with the events that describe what would be the next state and store information for the process if a particular event occurred.

  • State...