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Xdebug profiler

While Clockwork provides a lot of performance metrics and profiling features like timeline events, finding the problematic spot in your application can still be hard. Xdebug is a PHP extension, which provides an advanced profiler, collecting metrics about every single function call. Clockwork comes with a full-featured Xdebug profiler UI, you can find it in the performance tab.

The profiler UI will show you a breakdown of all function calls with their self and inclusive cost. You can toggle between execution time or memory usage metrics, exact or pecentual representation and of course the data is orderable and filterable.


Install the Xdebug extension via PECL (part of your PHP installation):

$ pecl install xdebug

Enable the PHP extension in your php.ini (location of php.ini and the xdebug extension path will depend on your operating system):


Now we need to enable the Xdebug profiler itself. You could enable the profiling for all requests, but collecting Xdebug profiles slows down the response time dramatically. That's why it's a good idea to enable Xdebug profiling only for certain requests. To do so, add following setting to your php.ini and you will be able to toggle whether Xdebug profiles should be collected in Clockwork profiler UI itself:


For more detailed information about installation and other awesome Xdebug features, check out the Xdebug website.