Re: Processes stuck on D state on Dual Opteron

Nick Piggin
2005-04-11T22:59:23Z

Claudio Martins wrote:

> Right. I'm using two Seagate ATA133 disks (ide controler is AMD-8111) each
> with 4 partitions, so I get 4 md Raid1 devices. The first one, md0, is for
> swap. The rest are
>
> ~$ df -h
> Filesystem Size Used Avail Use% Mounted on
> /dev/md1 4.6G 1.9G 2.6G 42% /
> tmpfs 1005M 0 1005M 0% /dev/shm
> /dev/md3 32G 107M 30G 1% /home
> /dev/md2 31G 149M 29G 1% /var
>
> In these tests, /home on md3 is the working area for stress.
>
> The io scheduler used is the anticipatory.
>

OK.

>
> OK, I'll try them in a few minutes and report back.
>

I'm not overly hopeful. If they fix the problem, then it's likely
that the real bug is hidden.

> I'm curious as whether increasing the vm.min_free_kbytes sysctl value would
> help or not in this case. But I guess it wouldn't since there is already some
> free memory and also the alloc failures are order 0, right?
>

Yes. And the failures you were seeing with my first patch were coming
from the mempool code anyway. We want those to fail early so they don't
eat into the min_free_kbytes memory.

You could try raising min_free_kbytes though. If that fixes it, then it
indicates there might be some problem in a memory allocation failure
path in software raid somewhere.

Thanks

--
SUSE Labs, Novell Inc.