Had nginx 1.0.5 running on a Fedora 15 system just fine for months. Upgraded the server from F15 to F17. At first, all seems well, but over time, I keep getting 500 errors on proxied sites. Logs say: "socket() failed (24: Too many open files) while connecting to upstream". Has anyone else had this experience? If so, what's the root cause?

Had to revert server back to a backup to get sites functional.