Debug Bar Slow Actions
Easily find out which actions and filters are the slowest during a page load.
Plugin tag: profiling
WP XHProf Profiler
Adds PHP profiling support to your Wordpress using Facebook's XHProf Profiler.
Debugger
You can use this plugin to manually log data or to capture logging on WordPress…
WPDB Profiling
This plugin will give you the total number of queries to the db per page,…
MySQL Profiler
Displays a list of each page's SQL queries and the functions calling them that can…
Simple Debug
Analyzes WordPress website performance, helps to locate slow function hooks.