Book Image

Mastering Elasticsearch 5.x - Third Edition

Book Image

Mastering Elasticsearch 5.x - Third Edition

Overview of this book

Elasticsearch is a modern, fast, distributed, scalable, fault tolerant, and open source search and analytics engine. Elasticsearch leverages the capabilities of Apache Lucene, and provides a new level of control over how you can index and search even huge sets of data. This book will give you a brief recap of the basics and also introduce you to the new features of Elasticsearch 5. We will guide you through the intermediate and advanced functionalities of Elasticsearch, such as querying, indexing, searching, and modifying data. We’ll also explore advanced concepts, including aggregation, index control, sharding, replication, and clustering. We’ll show you the modules of monitoring and administration available in Elasticsearch, and will also cover backup and recovery. You will get an understanding of how you can scale your Elasticsearch cluster to contextualize it and improve its performance. We’ll also show you how you can create your own analysis plugin in Elasticsearch. By the end of the book, you will have all the knowledge necessary to master Elasticsearch and put it to efficient use.
Table of Contents (20 chapters)
Mastering Elasticsearch 5.x - Third Edition
Credits
About the Author
Acknowledgements
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Chapter 7. Low-Level Index Control

In the last chapter, we learned about creating a multi-node cluster and then went through index distribution architecture in Elasticsearch, including choosing the right number of shards and replicas along with a detailed discussion on how routing works, how shard allocation works, and how to alter the default shard allocation behavior. In addition to that, we also discussed what query execution preference is and how to configure it. We also saw how data stripping works and considerations for creating multiple document types inside an Elasticsearch index.

In this chapter, we will cover some granular details of Apache Lucene scoring and how you can alter them and can choose the right scoring algorithm. We will also cover Near Real Time (NRT) searching and indexing and the transaction logs. You will also get to know about segment merging and removed merge policies inside Elasticsearch 5.0. At the end of the chapter, you will also find information about IO throttling...