I run a decently high-trafficked webserver (dedicated Apache/PHP), and while it works fine most of time, about once a day it dead-locks and refuses any new connections. Restarting Apache fixes the problem. I have caught it a few times right before this lockout, and Apache Status shows all W's (sending reply) for every request. The last error in the http-errors.log is that MaxClients was hit (which makes sense because no request is returning).
Do you guys have any ideas why an Apache request might decide to never return, or any thoughts on what could be going on here?