Benchmarking with Apache Bench

Last month, we looked at some of the issues that affect PHP performance and explored PHP caches and optimizers, two kinds of add-ons that can provide a substantial performance boost to your PHP web applications. Rather than dig into any of those products (they all have sufficient documentation and good support communities), let’s focus on a related issue: performance testing. Or, said another way, once you’ve installed a performance boosting add-on or made a configuration change, how can you determine if it’s helping or hurting?

Benchmarking and stress testing is a complex topic — especially on large, multi-tier web applications. Completing a valid, comprehensive benchmark of a complex application can take weeks of planning and development and is well beyond the scope of this article. So, let’s cover some basic ideas and introduce some of the tools you’ll need to get started.

When It’s Already…