Simon Slater wrote, On 03/10/2008 06:37 PM:
G'day all,
This is an inconvenience that I would like to get to the bottom of. I
have a PII 233MHz 512 MbRAM running FC6. All is fine until swap reaches
about 25% used then the system hangs. It will run for days with the
swap at 10-15%. My first thought was to run badblocks to see if that
was the problem, since it is an old drive, but couldn't find the swap
device with mount.
Been there, done that.
WARNING: before using badblocks in full rw mode on swap space, remember two
things:
1) some how you would have to convince mkswap to retake what ever label is
being used in /etc/fstab, or you would need to use a new label/device name in
/etc/fstab.
2) don't be using it for swap while checking it. :)
/sbin/swapon -s
will display which partitions/files are being used in the system for swap.
/sbin/swapoff -a
will turn swap off. probably should shut down any programs down that you don't
need so that you can get under 512MB, then badblocks (with full read/write
test and re-`mkswap -c` on it, or Use non-destructive read-write mode) sounds
like a reasonable thing.
If you find a single bad block, you should really be looking for new hardware.
I have done the thing where you partition around the bad blocks, but it only
buys you a little time.
If I understand the man-page for mkswap the -c will print the bad block
locations, it says nothing of setting up swap to avoid them.
My questions are: what would cause this system to hang when the swap
file is used?;
[from experience I know] Bad blocks in swap cause errors that look _just_ like
failing ram. That is, programs just die, system locks up in weird ways.
where is the swap file?;
Most times it is a swap partition, `/sbin/swapon -s` or `cat /proc/swaps` will
help here.
if in the VG, how do I umount it
to run badblocks?
/sbin/swapoff
Here is some output that may be useful.
Thanks.
Good luck.
--
Todd Denniston
Crane Division, Naval Surface Warfare Center (NSWC Crane)
Harnessing the Power of Technology for the Warfighter
