dovecot - Dec 2008 - Problem with imap running at 100%

I was doing some checks on a server and found an imap process running at 
100%, kill -9 was unable to kill it.

hammer ~ # lsof -p 1918
COMMAND  PID     USER   FD   TYPE DEVICE SIZE/OFF    NODE NAME
imap    1918 vpopmail  cwd    DIR    8,2       96  539699
/var/vpopmail/domains/maxpersuasion.com/kec
imap    1918 vpopmail  rtd    DIR    8,2      856       2 /
imap    1918 vpopmail  txt    REG    8,2   851832 3646578
/usr/libexec/dovecot/imap
imap    1918 vpopmail  mem    REG    8,2  1330888 2752698 /lib64/libc-2.8.so
imap    1918 vpopmail  mem    REG    8,2    14520 2753738 /lib64/libdl-2.8.so
imap    1918 vpopmail  mem    REG    8,2   114960 2753800 /lib64/ld-2.8.so
imap    1918 vpopmail    2w  FIFO    0,5      0t0  574015 pipe
imap    1918 vpopmail    6u  0000    0,6        0      10 anon_inode

strace & gdb can't seem to attach to the process.

The process was started 2 days ago.

It is dovecot 1.1.6

> an imap process running at 100%, kill -9 was unable to kill it.
I'm no a Linux expert, but from a BSD perspective, that seems to contradict
each other. Either the process is doing an uninterruptable sleep or consumes CPU
time. As said, I'm not a Linux expert, but can you find out what state the
process is in and, if waiting, what's the wait channel?

On Fri, 2008-12-12 at 03:07 -0500, nuitari-dovecot at nuitari.net
wrote:
> I was doing some checks on a server and found an imap process running at 
> 100%, kill -9 was unable to kill it.
See the subject "unkillable imap process(es) with high CPU-usage"
thread
that's going on, with the exact same issue..
http://dovecot.org/list/dovecot/2008-December/035662.html

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On Dec 12, 2008, at 10:07 AM, nuitari-dovecot at nuitari.net wrote:
> I was doing some checks on a server and found an imap process  
> running at 100%, kill -9 was unable to kill it.
What OS/distribution and kernel version are you using?

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>> I was doing some checks on a server and found an imap process running
at
>> 100%, kill -9 was unable to kill it.
>
> What OS/distribution and kernel version are you using?
Gentoo with 2.6.27-gentoo-r5
amd64, 2 dual core opterons

I think the user uses Outlook though, but I can check