We need to fetch mutual friend data for each one of our new users. (We're currently doing that through the REST API.) In load testing for an upcoming traffic surge, we ran into API throttling, which breaks our production site. Oops!
In the Insights -> Diagnostics pane, it looks like they issue throttling warnings before they actually throttle. Is there some way we can monitor those limits in code so that we back off gracefully?
You will want to watch for the two errors coming back, then put your next call on a wait timer.
See: http://www.fb-developers.info/tech/fb_dev/faq/general/gen_10.html for more information.