Debugging and Profiling in WordPress:" " " What Is My Site Doing?

Peter Baylies aka @pbaylies on Twitter

Semper Fi Web Design

Methodology• Troubleshooting - be systematic

• Test against a development server

• Deactivate conflicting plugins

• Test against a default theme

• When all else fails...

Getting Started• Edit your wp-config.php

• define( 'WP_DEBUG', true );

• define( 'WP_DEBUG_DISPLAY', false );

• Other options?

http://codex.wordpress.org/Debugging_in_WordPress !WP_DEBUG_LOG - debug.log file in /wp-content/ SCRIPT_DEBUG - use dev .css and .js for core SAVEQUERIES - track MySQL queries !

Advice and plugin recommendations too!

Debugging Tools• Debug Bar - It's like FireBug for WordPress.

• Debug Bar Extender - with even more features.

• Query Monitor - Another take on both and more.

• Collect all three!

• ...yes, there are lots more.

What is 'Profiling'?• extensive performance metrics

• data collection, data analysis

• can track function calls, runtimes, control flow

P3 Plugin Profiler• Made by GoDaddy

• Generates pretty graphs!

• It's ok I guess?

• Be careful interpreting its advice.

• Honestly - this isn't a real profiling tool at all.

XHProf• Made by Facebook

• It's a PHP extension - some assembly required.

• There's a WordPress plugin to help you use it: WP XHProf Profiler"

• Execution time and memory use of all functions

• Shows a call graph of all functions

XDebug• Full-featured PHP debugging extension.

• Again, some assembly required.

• But once you have it working, it's very handy.

• Can integrate with many code editors.

• In theory can even do breakpoints (!)

• http://xdebug.org/docs/remote

Live Demo!• This is the fun part.

• Which of these would you like to see more of?

• Where did I confuse you the most?

Questions?• Thank you!

• Find this presentation on SlideShare

• Find me on Twitter: @pbaylies