Re: xfs deadlock in stable kernel 3.0.4

Christoph Hellwig
2011-09-21T11:39:39Z

On Wed, Sep 21, 2011 at 09:36:42AM +0200, Stefan Priebe - Profihost AG wrote:
> >So far I haven't been able to recreate it. How many runs did you
> >normally need on 3.1-rc? Note that so far I've run my known working
> >kernel, I'll test your config plus the drivers I need next.
>
> I had only used 3.0.4 with bonnie++ to reproduce. 3.1-rc was running
> on a prod. system.
>
> Sadly i'm also not able to reproduce it reliable on every partition.
> Sometimes it works sometimes not. Just retrying does not help. I had
> to copy and delete random files from the part. and then start
> bonnie++ on it. Perhaps i can give you a dd dump of the partition.
> But i had to recreate one. My Intel SSD is now massivly slower than
> when i started the tests. No idea why.

So far it runs fine on 3.1-rc both with my default config and yours,
the latter had been running all night. This is on a 8-core Nehalem
with 8GB of memory, and a fast PCI-e flash device.

One thing I noticed is that your config seems to run many fs tasks
a lot slower than mine, but I'm not entirely sure why.

The only interesting things I noticed in your config where that you
use slub instead of slab, which does a lot of high order allocations
and has caused lots of trouble in the past, and that you enable
CONFIG_CC_OPTIMIZE_FOR_SIZE, which has caused mis-compilation
of complicated code in the past. I don't want to blame it directly,
but I could see how that causes problems with some of the atomic64_t
games XFS plays since 2.6.38.