Latest FC kernel still have SMP bugs?

Norman Gaywood norm at
Fri Apr 2 00:21:23 UTC 2004

On Thu, Apr 01, 2004 at 04:31:57PM -0500, Chris Miller wrote:
> On Thu, 2004-04-01 at 09:48, Mitch Wiedemann wrote:
> > Is the FC1 2.4.22-1.2174.nptl kernel still having problems with SMP and 
> > hanging?
> I run around 100 SMP servers with no problem.  
> Hardware.
> Dual Xeon servers with HT on supermicro server boards.
> Dual AMD on Tyan 2469,2468,2462
> Dual Opteron on Tyan 2880
> And I do run the fedora kernel.  Anything I can do to help let me know. 
> But I have never seen any of the problems anyone is talking about.

I'd be interested if you could run the script from:

and see how you go. The script creates a small file in /tmp, makes a
filesystem image out of that file, and then continuously does a
loop-back mount/umount until you get sick of it and ^C out.

Any FC1 SMP kernel I have used on several types of systems, including
AMD single processor systems running the athlon SMP kernel, will lockup
in less than 500 mount/umounts. Usually much faster.

Other kernels can do mount/umounts for as long as you want. I've gone
upto 20,000 before I ^C out.

This is the script:




echo Creating something to mount
dd if=/dev/zero of=${IMAGE} bs=1k count=${SIZE}
mke2fs -F -q ${IMAGE} ${SIZE}

echo Creating the mount point
mkdir -p ${MNTPOINT}

echo Now doing mount/umount until the system hangs
while true
  echo -en ${COUNT} "\r"
  mount -r -o loop -t ext2 ${IMAGE} ${MNTPOINT}
  umount ${MNTPOINT}
  COUNT=`expr ${COUNT} + 1`

Norman Gaywood, Systems Administrator
School of Mathematics, Statistics and Computer Science
University of New England, Armidale, NSW 2351, Australia

norm at            Phone: +61 (0)2 6773 2412    Fax:   +61 (0)2 6773 3312

Please avoid sending me Word or PowerPoint attachments.

More information about the users mailing list