Application Profiling with PHP

As an application grows over time, added functionality can start to drag on execution time. You may have a once simple order process that now connects to multiple APIs, updates CRM data, generates invoices, processes payments and sends out multiple email. It’s slowed to the point of appearing broken and users are dropping out.

Something has to be done, but where do we start? How can we pinpoint the precise code slowing us down?

Using application profiling we can get a glimpse into the inner workings of our script. In a PHP environment that can be done with the Xdebug extension and a visualization tool such as kCachegrind, or Profiling Viewer.

We'll walk through the steps to install Xdebug, capture profiling information and make some of sense of it.