High MySQL CPU Usage due to select query on wp_icl_string_pages

A few days ago one of our client’s websites was causing high MySQL processor usage. To narrow down the particular site and table causing the problem we ran mysqladmin processlist and it came back with the particular DB causing the high usage and the table: wp_icl_string_pages

This is a table that’s part of the WordPress plugin WPML for translation of websites into multiple languages. This issue also seems to be pretty common as of late. At first I just thought it was the issue described in that forum thread, so I updated the plugin to the beta version as recommended to resolve the issue. Only the issue was not resolved.

After some extensive troubleshooting I finally found the true cause of this problem. Under WPML’s settings there was an option called “Track where strings appear on site” which is supposed to only be used during development. Apparently the developer of the site had forgot to disable this option, causing the high CPU usage upon page load. By disabling this option, the CPU usage has returned to normal.

Hopefully this helps others in the same situation.