XHProf is described as 'Function-level hierarchical profiler for PHP and has a simple HTML based navigational interface. The raw data collection component is implemented in C (as a PHP extension). The reporting/UI layer is all in PHP' and is an app in the development category. There are 1 alternatives to XHProf for Mac and Linux. The best XHProf alternative is SPX, which is both free and Open Source.
SPX, which stands for Simple Profiling eXtension, is just another profiling extension for PHP. It differentiates itself from other similar extensions as being: totally free and confined to your infrastructure (i.e. no data leaks to a SaaS).
