I've noticed a curious issue recently on my server.

I am running Ubuntu 10.04, Nginx, and PHP-FPM using Brian Mercer method.

I recently updated the server, and then also updated my PHP-FPM config to allow dynamic child processes instead of just static.
I've noticed now that *one* of my domains (all my domains within the same server and same worker group) will periodically hit a 502 Bad Gateway error, which remains up for that domain, while other sub domains and other websites hosted on my server, have no problem.

Restarting PHP-FPM resolves the issue.

What puzzles me is, why would it toss this error just for *one* domain, not the rest?
I'm assuming this is actually not a problem in Nginx, but moreso in PHP-FPM, regarding the number of processes, requests, etc?


BTW, I realize this is not a support forum for PHP-FPM, but I know many Nginx users also use PHP-FPM, so I figured this is one of the better locations to get an intelligent response. If my post is completely not wanted here, let me know :-)

All feedback appreciated!

Thanks!