I am running
apache on Fedora with
mod_perl. The server forks a process to send an email frequently - and the fork exits.
Suddenly, I got:
Cannot fork: Cannot allocate memory. There was plenty of free memory (I did not look too closely, but there was more memory free than in use), not too many
apache processes running - 10?, low cpu usage, close to 0. Restarting the server httpd graceful resolved the issue.
What would cause something like this? Is it possible that I got into some kind of a state where the problem was allocating too many processes in the system - and with dropping load failed to recover?
Unfortunately I do not have too much info as I was panicking and trying to get the site up instead of running diagnostics. :-) So my question is very general: is there anything that's not obvious that would create this behavior when too many processes are allocated? Anything specific to forking from within apache? etc