Re: Xfs delaylog hanged up

Spelic
2010-11-24T00:55:49Z

On 11/23/2010 09:46 PM, Dave Chinner wrote:
> Hmmmm. We get plenty of reports about problems with 3ware RAID
> controllers, many of which are RAID controller problems. Can you
> make sure you are running the latest firmware on the controller?
>

No, sorry, my firmware is: FE9X 4.06.00.004

But when controllers hang, there is usually something in dmesg, and in
my case there wasn't. Then after a while it resets (it has something
like a watchdog in it).
In the past during testing I did have reproducible hangups on high load
with these controllers (seemed like a lost interrupt), but they were
fixed by disabling NCQ.
The controller would reset in those cases, drives caches would reset to
"off", and there were entries in dmesg.
But that issue was definitely fixed by disabling NCQ: I tested many
times with and without NCQ with reproducible results; and after that we
had reliable operation for more than 1 year on that machine.

> I've been unable to reproduce the problem with your test case (been
> running over night) on a 12-disk, 16TB dm RAID0 array, but I'll keep
> trying to reproduce it for a while.

It seems to me that 12 disk raid0 dm is quite different from 16 disk md
raid5 array because you don't have the stripe cache and there are likely
to be fewer in-flight operations, if it was a pool of something which
was drained you might not hit it... But I understand that you had the
raid0 array already up :-D I'll see if I can reproduce this but I can't
guarantee: the machine should go back to production very soon.
If I hit it again, what should I look at?