From Facebook Developers Wiki

[edit] timeouts

Is the timeout for fb:ref url's much shorter than for normal FBML canvas pages? I have a PHP script which returns valid FBML that renders fine normally, but is a bit slow; I'm trying to speed things up (and reduce load on my server) by caching with fb:ref. Unfortunately, sometimes the fb:ref page gives an error "No data stored for ref, url:.....". Server logs confirm that facebook is requesting the page - and sometimes it works ok. My only guess is that it times out. Is there anything I can do? The timeout time seems quite short.

When you call facebook.fbml.refreshRefUrl("http://www.mysite.com/someurl.php") is the new data fetched immediately or is Facebook smart enough to wait until that fb:ref is used again (if ever)?

It convenient that "test of fbml <fb:name uid="219770" />" your Refresh would update all users profiles with the above can you give a better example of what the Refresh does for 100,000 users please for me it seems the REF is used for static content within the Profile and SetFBML for dynamic content that needs to be put on cron

[edit] handle fbml error

I've just tried to use <fb:if-is-own-profile> in the data for a <fb:ref handle.. and it doesn't display. 717400660 19:35, 18 July 2008 (PDT)