Drupal for Facebook Slowing Down Your Site?
A user recently reported Drupal for Facebook causing pages to load very slowly. Here's a quick fix.
The first rule of troubleshooting Drupal for Facebook is "enable the fb_devel.module". This module will alert you to all sorts of potential errors, perform sanity checks and write verbose data to Drupal's watchdog log. It is essential to enable fb_devel.module when you first develop a Facebook App.
The exception that proves the first rule is this: if the problem you are troubleshooting is performance, disable fb_devel.module (and while you're at it, disable devel.module). With those modules disabled, try to reproduce the performance issues. With any luck, fb_devel.module's sanity checks are causing the delay.
That's it. fb_devel.module is slow, because it is doing its job. Disable it on live websites, and when testing performance.