[Dovecot] Unkillable imap process?

[Darren Pilgrim]

Johan Persson wrote:
> the imap process was hogging 100% of the CPU and it had been 
> running so for over an hour.
[...]
> I tried to recover by gracefully shutting down dovecot and when that didn't 
> stop the imap process I first tried to be nice by sending it the TERM signal 
> and when that didn't do it, the KILL signal.
> 
> However, I was not able to stop the imap process. I then decided to recycle 
> the server and initiated a shutdown. However, not even that was able to 
> complete (since the shutdown process seemed to be hanging on not being able to 
> stop the imap process).
[...]
>  1.1.7: /etc/dovecot/dovecot.conf
> # OS: Linux 2.6.27.7-9-pae i686 openSUSE 11.1 (i586) ext3

There was a thread on this list in December titled, "Dovecot imap
processes pinning CPU," that talked about this.  There's a bug in the
linux kernel that creates unkillable, runaway processes when file
monitoring is enabled.  There's a patch[1], and it's supposedly fixed in
2.6.27.10.

1:
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=711a49a07f84f914aac26a52143f6e7526571143