My previous blog entry used Eaccelerator as a php cache, but it does not appear to be actively maintaned.
In my research for a suitable and robust alternative, I recognized that a lot of large sites were using APC, and it was compatible with my desired application (Moodle)
APC (Alternative PHP Cache) is a free, open, and robust framework for caching and optimizing PHP intermediate code. (taken from: http://pecl.php.net/package/APC)
In order to avoid installation conflicts from the base repository, it was much simpler to compile the APC package from source for the php 5.3 on a CentOS 5.x installation.
0. Login as root
1. Go to temp folder and download the latest tarball
2. Extract to temp
tar xzvf APC-3.1.9.tgz
3. Configure and Install
**amended on 05-07-2012, added pcre-devel install as suggested by yaroslav.
yum install pcre-devel
4. Create APC config filenano /etc/php.d/apc.ini
Add to file
apc.enabled = 1
apc.shm_segments = 1
apc.shm_size = 64M
apc.max_file_size = 10M
Further information on advanced tweaking of configuration items here: http://www.php.net/manual/en/apc.configuration.php
5. Restart the webserver
service httpd restart
6. Check to see if APC was installed properly
Add to file
Save and Exit
Launch from web browser: http://yourserver.com/phpinfo.php
The APC configuration item should be found on the page.
7. Install the APC monitor
Copy APC Monitoring file into web root
cp /temp/APC-3.1.9/apc.php /var/www/html/
(There are options to secure this file, see the website for further details: http://pecl.php.net/package/APC)
Check the APC monitor
Launch from web browser: http://yourserver.com/apc.php
*A page should load displaying cache information and host status.
That's it. A quick and painless method of installing the APC Cache for php 5.3 on CentOS 5.x.