[Dovecot] file descriptor leak?

[Steven F Siirila]

On Wed, Jan 03, 2007 at 11:15:01PM +0200, Timo Sirainen wrote:
> On 3.1.2007, at 22.54, Steven F Siirila wrote:
> 
> >Jan  3 13:03:14 hostname dovecot-auth[5799]: crypt: fdopen(265)  
> >failed: Too many open files
> >Jan  3 13:03:14 hostname dovecot-auth[5799]: crypt: fdopen(265)  
> >failed: Too many open files
> >Jan  3 13:03:15 hostname dovecot: auth(default): pam(username, 
> >10.1.1.1): Child process died
> >Jan  3 13:03:15 hostname dovecot: auth(default): PAM: Child 5799  
> >died with signal 11
> >
> >Questions:
> >
> > 1) Is there a file descriptor leak, or are there supposed to be  
> >this many
> >    open pipes in dovecot-auth?  (master dovecot has way more than  
> >256 at
> >    this point, but apparently does not use stdio.)
> 
> Each imap-login and pop3-login connects to dovecot-auth. So if you've  
> about 250 SSL/TLS connections, or 250 users logging in at the same  
> time, and login_process_per_connection=yes, I guess this could  
> happen. So login_process_per_connection=no should work around this.

First off, we don't allow non-SSL/TLS connections.
When you say "I guess this could happen" are you saying that there might
be a file descriptor leak?  Is it normal to have hundreds of file descriptors
in used by the master dovecot and the dovecot-auth process?  What is the
formula for how many file descriptors I SHOULD be seeing in use concurrently
for master dovecot, dovecot-auth, etc.?

I will try switching to login_process_per_connection=no, hoping that the
problem with file descriptors doesn't move from dovecot-auth to imap-login !

> > 2) Has anyone tried compiling Dovecot in 64-bit mode (-xarch=v9)?   
> >I have
> >    tested the fact that this removes the >255 fd limitation in  
> >Solaris 9/10.
> 
> A lot of people are using 64bit Dovecot at least with x86-64.
> 
> I don't see why crypt() want to open any files though.

Me either.  Doesn't the error message imply that crypt is calling fdopen?

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