RHEL4 Sun Java Messaging Server deadlock (was: redhat-list Digest, Vol 83, Issue 1)

[(Imed Chihi) عماد الشيحي]

> Date: Mon, 03 Jan 2011 10:51:58 -0500
> From: John Dalbec <jpdalbec at ysu.edu>
> To: redhat-list at redhat.com
> Subject: RHEL4 Sun Java Messaging Server deadlock
> Message-ID: <4D21F09E.3070100 at ysu.edu>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> Sun Java(tm) System Messaging Server 6.2-9.20 (built Jul 15 2010)
> libimta.so 6.2-9.20 (built 01:27:24, Jul 15 2010)
> Linux myysumail.ysu.edu 2.6.9-89.31.1.ELhugemem #1 SMP Mon Oct 4
> 22:04:11 EDT 2010 i686 i686 i386 GNU/Linux
>
> The IMAPd process appears to get into a deadlock with pdflush and
> kjournald.  The mailboxes were initially stored on a disk partition but
> I'm in the process of migrating them to a LVM logical partition.  Both
> partitions are ext3.  I worry about using ext2 because a fsck takes
> about 90 minutes.

Try collecting the output of Alt+SysRq+m and Alt+SysRq+t when this
deadlock occurs.  I remotely recall a case where one of the VM threads
starves the system of CPU cycles on RHEL 4.

> The server has 32GB RAM.  Right now Committed_AS is around 4GB, but the
> system is lightly loaded.  I'm running a 32-bit kernel because the
> application vendor doesn't support 64-bit.

Running a 32-bit kernel with more than, say, 16 GB of RAM will always
get you into trouble.  RHEL 4 does have multilib support, so you
should be able to run a 32-bit application atop a 64-bit installation.

 -Imed

-- 
Imed Chihi - عماد الشيحي
http://perso.hexabyte.tn/ichihi/