[Dovecot] dovecot-auth file descriptor usage

[Steven F Siirila]

On Tue, Jan 16, 2007 at 11:37:00PM +0100, Nicolas STRANSKY wrote:
> Le 16.01.2007 23:26, Timo Sirainen a écrit :
> 
> > No, non-SSL exits the imap-login processes after login, so that has
> > never reserved fds. So the fix was for SSL connections, and I tested SSL
> > connections..
> > 
> > I'm now just wondering if it's only dovecot-auth that doesn't notice the
> > socket closing for some reason, or if the imap-login processes proxying
> > SSL didn't really close the socket after all.
> 
> I am also experiencing an increased file descriptors usage on a server
> with several hundreds of users (running debian sarge amd64) since I'm
> using rc15. rc17 did not fix the problem. The server was formerly
> running fine with beta8.
> The problem is that when the file descriptors limit is reached, dovecot
> stops responding to new connections or responds strangely (thunderbird
> says that the server is not an imapV4 server) but nothing is logged
> anywhere. The only fix is a restart.

This may be a different, more basic issue.  Try using "ulimit -n unlimited"
or whatever equivalent command you have on Debian to remove the file
descriptor limitation.  From my experience, both dovecot master and the
dovecot-auth process require well over 256 file descriptors in normal
operation.  The master process needs one for every child process in order
to do logging for that child process.  The auth process seems to have one
open for every imap-login "listening" or "SSL Proxying" process you have.
(Timo, correct me if I'm wrong on this.)

> -- 
> Nico
> Les plus grands ne sont pas ceux qui ne tombent
> jamais, mais ceux qui se relèvent toujours.

-- 

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