Speed up PHP with APC on Ubuntu 10.04LTS

Ubuntu 10.04 LTS makes it quite simple to set up a basic LAMP server using tasksel; however, the default PHP set up does not include APC, the Alternative PHP Cache, which speeds up many PHP applications like Drupal. In the past, setting up APC involved using PECL or installing from source, but with Ubuntu Lucid, the process has been simplified using apt-get.

First, let me identify my demo system. It is running Ubuntu 10.04 LTS Lucid and has been patched to the latest version:

$ uname -a
Linux demo 2.6.32-24-generic #43-Ubuntu SMP Thu Sep 16 14:17:33 UTC 2010 i686 GNU/Linux
$ lsb_release -a
No LSB modules are available.
Distributor ID:	Ubuntu
Description:	Ubuntu 10.04.2 LTS
Release:	10.04
Codename:	lucid
$ sudo apache2ctl status | grep "Server Version"
Server Version: Apache/2.2.14 (Ubuntu) PHP/5.3.2-1ubuntu4.7 with Suhosin-Patch
$ apt-cache show php-apc | grep Version
Version: 3.1.3p1-2

Ubuntu has added a Debian package into universe that allows APC to be added to any system quite easily:

$ sudo apt-get install php-apc
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Suggested packages:
The following NEW packages will be installed:
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
Need to get 0B/77.2kB of archives.
After this operation, 217kB of additional disk space will be used.
Selecting previously deselected package php-apc.
(Reading database ... 28911 files and directories currently installed.)
Unpacking php-apc (from .../php-apc_3.1.3p1-2_i386.deb) ...
Processing triggers for libapache2-mod-php5 ...
 * Reloading web server config apache2
Setting up php-apc (3.1.3p1-2) ...

Note: You must restart the web server to begin using APC

$ sudo apache2ctl graceful

Out of the box (er…package), APC has some sane defaults. If you are “a serious user,” you will want to change your configuration yourself. Seriously, that is what the documentation says:

    …serious users should consider tuning the following parameters…

To tweak your very serious APC installation, you can change the settings manually (using vim):

$ sudo vim /etc/php5/conf.d/apc.ini

The APC configuration file is seriously barren; it is little more than an extension include directive. You can add extra keys after reading the APC’s online documentation related to settings.

Finally, there is a small php script that provides more information on the operation of the APC module. Copy it to your web root and decompress it. You should change the default username and password used to protect the script by changing the username and password variables directly in the PHP code:

$ sudo cp /usr/share/doc/php-apc/apc.php.gz /var/www
$ sudo gzip -d /var/www/apc.php.gz
$ sudo vim /var/www/apc.php

Change credentials near line 41:

defaults('ADMIN_USERNAME','apc'); // Admin Username
defaults('ADMIN_PASSWORD','password'); // Admin Password - CHANGE THIS TO ENABLE!!!

Now, view your APC page (assuming your web server is at