Latest FC kernel still have SMP bugs?

[Norman Gaywood]

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:

http://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=109962#c40

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:

#!/bin/sh

NAME="hangemhi"
SIZE=6000

MNTPOINT=/tmp/${NAME}
IMAGE=/tmp/${NAME}.img

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
COUNT=1
while true
do
  echo -en ${COUNT} "\r"
  mount -r -o loop -t ext2 ${IMAGE} ${MNTPOINT}
  umount ${MNTPOINT}
  COUNT=`expr ${COUNT} + 1`
done


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

norm at turing.une.edu.au            Phone: +61 (0)2 6773 2412
http://turing.une.edu.au/~norm    Fax:   +61 (0)2 6773 3312

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