Book Image

Mastering Hadoop 3

By : Chanchal Singh, Manish Kumar
Book Image

Mastering Hadoop 3

By: Chanchal Singh, Manish Kumar

Overview of this book

Apache Hadoop is one of the most popular big data solutions for distributed storage and for processing large chunks of data. With Hadoop 3, Apache promises to provide a high-performance, more fault-tolerant, and highly efficient big data processing platform, with a focus on improved scalability and increased efficiency. With this guide, you’ll understand advanced concepts of the Hadoop ecosystem tool. You’ll learn how Hadoop works internally, study advanced concepts of different ecosystem tools, discover solutions to real-world use cases, and understand how to secure your cluster. It will then walk you through HDFS, YARN, MapReduce, and Hadoop 3 concepts. You’ll be able to address common challenges like using Kafka efficiently, designing low latency, reliable message delivery Kafka systems, and handling high data volumes. As you advance, you’ll discover how to address major challenges when building an enterprise-grade messaging system, and how to use different stream processing systems along with Kafka to fulfil your enterprise goals. By the end of this book, you’ll have a complete understanding of how components in the Hadoop ecosystem are effectively integrated to implement a fast and reliable data pipeline, and you’ll be equipped to tackle a range of real-world problems in data pipelines.
Table of Contents (23 chapters)
Title Page
Dedication
About Packt
Foreword
Contributors
Preface
Index

NameNode


NameNode is mater daemon in the HDFS and every client request for read and write goes through NameNode. If NameNode performance decreases, then it will eventually lead to the application performance decreases because NameNode will respond slowly to any request made to it. Let's look into how we do profiling for NameNode performance.

NNBench

NameNode is the heart of the Hadoop cluster. Any file operations in HDFS first goes through the NameNode. NameNode, apart from managing file operations, keeps track of all file locations on DataNodes. So it is important that you test NameNode performance against chosen hardware configurations. NNBench is one such tool that can help you in evaluating that. Based on the NNBench output, you can decide on the optimal configuration of NameNode as well. The following is the command to run NNBench (Ref: Hadoop 3 Apache Document):

hadoop jar <HADOOP_CLIENT_INSTALLATION_PATH>/hadoop-mapreduce-client-jobclient-<HADOOP_VERSION>-tests.jar nnbench...