Xdebug

According to the official page on the xdebug Profiler:

Xdebug’s built-in profiler allows you to find bottlenecks in your script and visualize those with an external tool such as KCacheGrind or WinCacheGrind. Xdebug’s Profiler is a powerful tool that gives you the ability to analyze your PHP code and determine bottlenecks or generally see which parts of your code are slow and could use a speed boost.

There’s some serious information in these little files too. By importing the debug files into a tool called WinCacheGrind you can view the files in a format that won’t make you stick a knife in your eyes.

Here’s a small example of the exported data:

version: 0.9.6
cmd: C:ProjectFilescat_v2index.php
part: 1
 
events: Time
 
fl=php:internal
fn=php::define
3 7
 
fl=php:internal
fn=php::get_include_path
4 6
 
fl=php:internal
fn=php::set_include_path
4 5

To get started first make sure you have Xdebug 2.0 installed. To check, execute the below in a dos prompt:

php -v

You should see something like the below:

PHP 5.2.6 (cli) (built: May  2 2008 18:02:07)
Copyright (c) 1997-2008 The PHP Group
Zend Engine v2.2.0, Copyright (c) 1998-2008 Zend Technologies
with Xdebug v2.0.3, Copyright (c) 2002-2007, by Derick Rethans

If not, you’ll need to download and install Xdebug.

If you do have Xdebug, modify your php.ini to include the below after the Xdebug init call:

xdebug.profiler_enable = 1
xdebug.profiler_output_dir = "C:/path/to/profiler/storage"

Once you’ve configured php you might need to restart your server depending on how php is implemented. Either way, to generate a profile output just execute a script; the output should be written to the directory you set in the xdebug.profiler_output_dir.

All that’s left is to open the profile output in WinCacheGrind.

WinCacheGrind

Notes:
The profilers seems to only record data if the script is executed from the command line.
Download WinCacheGrind