Book Image

Linux Shell Scripting Cookbook, Second Edition - Second Edition

Book Image

Linux Shell Scripting Cookbook, Second Edition - Second Edition

Overview of this book

The shell remains one of the most powerful tools on a computer system — yet a large number of users are unaware of how much one can accomplish with it. Using a combination of simple commands, we will see how to solve complex problems in day to day computer usage.Linux Shell Scripting Cookbook, Second Edition will take you through useful real-world recipes designed to make your daily life easy when working with the shell. The book shows the reader how to effectively use the shell to accomplish complex tasks with ease.The book discusses basics of using the shell, general commands and proceeds to show the reader how to use them to perform complex tasks with ease.Starting with the basics of the shell, we will learn simple commands with their usages allowing us to perform operations on files of different kind. The book then proceeds to explain text processing, web interaction and concludes with backups, monitoring and other sysadmin tasks.Linux Shell Scripting Cookbook, Second Edition serves as an excellent guide to solving day to day problems using the shell and few powerful commands together to create solutions.
Table of Contents (16 chapters)
Linux Shell Scripting Cookbook
About the Authors
About the Reviewers

Monitoring disk activity

Going by the popular naming convention of monitoring tools ending in the word 'top' (the command used to monitor processes), the tool to monitor disk I/O is called iotop.

Getting ready

iotop doesn't come preinstalled with most Linux distributions, you will have to install it using your package manager.

How to do it...

There are multiple ways of using iotop to perform I/O monitoring, some of which we will see in this recipe:

  1. For interactive monitoring, use:

    # iotop -o

    The -o option to iotop tells it to show only those processes which are doing active I/O while it is running. It is a useful option to reduce the noise in the output.

  2. For non-interactive use from shell scripts, use:

    # iotop -b -n 2

    This will tell iotop to print the statistics two times and then exit, which is useful if we want this output in a shell script and do some manipulation on it.

  3. Monitor a specific process using the following:

    # iotop -p PID

    Put PID of the process that you wish to monitor, and iotop...