How to Install the Memcached PHP Extension on Ubuntu 15.04

Memcached is a distributed, high-performance, in-memory caching system that is primarily used to speed up sites that make heavy use of databases. It can, however, be used to store objects of any kind. Nearly every popular CMS has a plugin or module to take advantage of Memcached, and many programming languages have a Memcached library, including PHP, Perl, Ruby, and Python. Memcached runs in memory and is thus quite speedy since it does not need to write data to disk.

Pre-Flight Check

• These instructions are intended specifically for installing the Memcached PHP Extension on a single Ubuntu 15.04 node.
• I’ll be working from a Liquid Web Core Managed Ubuntu 15.04 server, and I’ll be logged in as root.
• Follow our tutorial on How to Install Memcached on Ubuntu 15.04 prior to this KB!

Step #1: Install the Memcached PHP Extension

As a matter of best practice we’ll update our packages:

apt-get update

Then installing PHP Memcached extension and related packages is now as simple as running just one command::

apt-get install php5-memcached

Step #2: Verify Installation

Use the following command to view information on the installed PHP modules:

php -m | grep memcached

The result should be similar to:

memcached

You can also verify the configuration of PHP with phpinfo. Follow our tutorial: How To: Check PHP Modules With phpinfo