I have been managing a site that uses a phpBB forum for some time now. The forum has been growing and now has 160+ registered users using it daily. Recently (over the past month or so) I and other users have been getting "500 internal server error" messages at random, most often when trying to post or edit a forum post. This often results in people double posting when they shouldn't. I've tried to pinpoint the problem but it just seems to be getting worse especially after our recent upgrade to phpBB 3.0.8.
These "500" messages seem to sometimes go away, and sometimes they pop up in much higher frequency than normal. Looking in the server logs, there are lots of errors like this:
[Fri Jan 14 02:19:38 2011] [error] [client 220.127.116.11] Premature end of script headers: posting.php, referer: http://www.love-shy.com/lsbb/posting.php?mode=edit&f=3&p=175614
I read a dreamhost thread on the matter, and among many suggestions was the idea that the site may be running out of memory and needs an upgrade. There was also a suggestion regarding search indexers getting stuck in a loop, though I see no evidence of this. What can I do at this point?[/code]