Book Image

Learning Spark SQL

By : Aurobindo Sarkar
Book Image

Learning Spark SQL

By: Aurobindo Sarkar

Overview of this book

In the past year, Apache Spark has been increasingly adopted for the development of distributed applications. Spark SQL APIs provide an optimized interface that helps developers build such applications quickly and easily. However, designing web-scale production applications using Spark SQL APIs can be a complex task. Hence, understanding the design and implementation best practices before you start your project will help you avoid these problems. This book gives an insight into the engineering practices used to design and build real-world, Spark-based applications. The book's hands-on examples will give you the required confidence to work on any future projects you encounter in Spark SQL. It starts by familiarizing you with data exploration and data munging tasks using Spark SQL and Scala. Extensive code examples will help you understand the methods used to implement typical use-cases for various types of applications. You will get a walkthrough of the key concepts and terms that are common to streaming, machine learning, and graph applications. You will also learn key performance-tuning details including Cost Based Optimization (Spark 2.2) in Spark SQL applications. Finally, you will move on to learning how such systems are architected and deployed for a successful delivery of your project.
Table of Contents (19 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Introducing performance tuning in Spark SQL


Spark computations are typically in-memory and be bottlenecked by the resources in the cluster: CPU, network bandwidth, or memory. In addition, although the data fits in memory, network bandwidth may be challenging.

Note

Tuning Spark applications is a necessary step to reduce both the number and size of data transfer over the network and/or reduce the overall memory footprint of the computations.

In this chapter, we will focus our attention on Spark SQL Catalyst because it is key to deriving benefits from a whole set of application components.

Spark SQL is at the heart of enhancements to Spark recently, including ML Pipelines, Structured Streaming, and GraphFrames. The following figure illustrates the role Spark SQL plays the Spark Core and the higher-level APIs on top of it:

In the next several sections, we will the fundamental understanding required for tuning Spark SQL applications. We will start with the DataFrame/Dataset APIs.