Book Image

PostgreSQL High Availability Cookbook - Second Edition

By : Shaun Thomas
Book Image

PostgreSQL High Availability Cookbook - Second Edition

By: Shaun Thomas

Overview of this book

Databases are nothing without the data they store. In the event of a failure - catastrophic or otherwise - immediate recovery is essential. By carefully combining multiple servers, it’s even possible to hide the fact a failure occurred at all. From hardware selection to software stacks and horizontal scalability, this book will help you build a versatile PostgreSQL cluster that will survive crashes, resist data corruption, and grow smoothly with customer demand. It all begins with hardware selection for the skeleton of an efficient PostgreSQL database cluster. Then it’s on to preventing downtime as well as troubleshooting some real life problems that administrators commonly face. Next, we add database monitoring to the stack, using collectd, Nagios, and Graphite. And no stack is complete without replication using multiple internal and external tools, including the newly released pglogical extension. Pacemaker or Raft consensus tools are the final piece to grant the cluster the ability to heal itself. We even round off by tackling the complex problem of data scalability. This book exploits many new features introduced in PostgreSQL 9.6 to make the database more efficient and adaptive, and most importantly, keep it running.
Table of Contents (18 chapters)
Title Page
About the Author
About the Reviewer
Customer Feedback

Tweaking XFS performance

When it comes to performance optimization on XFS filesystems, allocation groups are only the beginning. To maintain a high-availability PostgreSQL server, we want to get the most out of XFS. For us, this means using specific mount options.

Thankfully, unlike formatting, mount options can be changed frequently and require very little downtime. Though it isn't essential that we apply these values immediately, the options discussed in this recipe are our recommendation for this stack.

Getting ready

In order to mount an XFS filesystem, we need one to exist. Please follow the recipe contained in Formatting an XFS filesystem before continuing.

How to do it...

Assuming pg1 is our current primary node, follow these steps as the root user:

  1. Use this command to find the Linux kernel version:
uname -r
  1. Create a mount location by executing this command:
mkdir /db
  1. For kernel versions 3.0 and above, mount the filesystem with this command:
mount -t xfs -o noatime,nodiratime \