freebsd stable - Sep 2012 - qmail-remote uses 100% CPU when delivering to certain hosts

Hi.

Firstly, my environment:

FreeBSD isis.poly.edu 9.1-RC1 FreeBSD 9.1-RC1 #0: Thu Sep 20 23:42:23 
EDT 2012     boris@jails.isis.poly.edu:/usr/obj/usr/src/sys/GENERIC  amd64

qmail-tls-1.03.20021228_4

I have noticed that qmail-remote spins around using 100% CPU forever 
when delivering mail to a select few hosts. I believe this all to be in 
userspace as top reports that the CPU is busy with only userspace code. 
This has never happened when the machine was running 8.0-RELEASE, but 
happens with 8.2-RELEASE and 9.1-RC1.

The environment this happens in is a jail.

Calling truss on the offending processes produces no output, with truss 
in the "wait" state forever. I've tcpdumped the conversation
between the
qmail-remote process and the remote host. It is attached with this e-mail.

Thoughts?

-Boris
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On Sep 28, 2012, at 10:12 PM, Boris Kochergin <spawk@acm.poly.edu> wrote:
> Hi.
> 
> Firstly, my environment:
> 
> FreeBSD isis.poly.edu 9.1-RC1 FreeBSD 9.1-RC1 #0: Thu Sep 20 23:42:23 EDT
2012     boris@jails.isis.poly.edu:/usr/obj/usr/src/sys/GENERIC  amd64
> 
> qmail-tls-1.03.20021228_4
> 
> I have noticed that qmail-remote spins around using 100% CPU forever when
delivering mail to a select few hosts. I believe this all to be in userspace as
top reports that the CPU is busy with only userspace code. This has never
happened when the machine was running 8.0-RELEASE, but happens with 8.2-RELEASE
and 9.1-RC1.
> 
> The environment this happens in is a jail.
> 
> Calling truss on the offending processes produces no output, with truss in
the "wait" state forever. I've tcpdumped the conversation between
the qmail-remote process and the remote host. It is attached with this e-mail.
> 
> Thoughts?
> 
> -Boris
> <qmail-remote.pcap>


Boris the messages that are in the delivery queue ,at this time, can you share
any details on them are they big, small etc . Also what file system do you use
for the hauls .