On Thu, 2011-10-06 at 12:42 +0100, Michael Moritz wrote: > Hi > > I've found an older thread > http://www.dovecot.org/list/dovecot/2010-March/047886.html which mentions > that this is a bug in version 1. I'm on Debian squeeze (1:1.2.15-7) and got > errors like these recently > > Oct 5 11:29:29 mail dovecot: dovecot: pipe() failed: Too many open files > Oct 5 11:29:32 mail dovecot: dovecot: pipe() failed: Too many open files > Oct 5 11:29:32 mail dovecot: dovecot: Temporary failure in creating login > processes, slowing down for now
These errors come from the dovecot master process. Each child process uses up a few fds for pipes. > As a work around I've increased login_max_processes_count from 256 to 512 and > it seems to have helped (as I suspected stale opened files). That only makes it easier to reach, since now there can be more child processes eating up more fds. > My colleague thinks it's hitting the kernel open file limit ulimit -n > (currently at 1024) but I don't see how that could happen if the number of > process is nowhere near that. I don't remember how many fds each process takes in v1.x, probably between 1 and 3. So if you for a while had hundreds of imap or pop3 processes, you could run into that limit. v2.x doesn't use as many fds.
