Most web servers are able to handle "normal" traffic and there are plenty of websites which doesn't have so much traffic. So maybe you ask yourself: Why should you cache your PHP powered website? The apache web server is able to serve many, many files at the same time, but all these files need to be static. A PHP script is parsed by the web server and next the generated HTML data is send to the client (web browser). While this happens the server need to use much more memory than by sending a file to a web client. Imagine what happens if you run/parse a page which is build with WordPress...

He points out the WordPress Super Cache plugin and mentions that there's lots of other tools out there in the form of plugins or things like eAccelerator. He even includes a simple custom caching script that grabs the contents of a remote file and caches it locally for twenty-four hours.

Some websites use other technologies like Java and face the exact same problems. There are different variables involved here and the most common one is database. So I thought i would post a couple of articles related to performance and tuning.

This this post of the series focuses on the first of the two - APC - and talks about places it's used and includes some general performance recommendations. These include "Don't try to throw everything at your poor database" and the importance of XDebug.

In the article, he looks at what accelerators are, how they work, and some of the ones that are currently out there in the market:

• APC
• eAccelerator
• Zend Platform

With the ground rules established, he breaks out the analysis into a few different rounds/categories including: support/maintenance, the accelerator's actual performance (including the code they used) and the results he discovered (all graphed out), and, finally, how they handle file updates made to the system.

In the end, there just isn't one that's a clear winner. What it really boils down to is what kind of situation you're in - Zend's option is good if you can pay for everything, otherwise, you'd do well to go with eAccelerator.