high load and xfsaild in d

[Dave Chinner]

On Thu, Nov 22, 2012 at 08:34:06PM -0800, Keith Keller wrote:
> On 2012-11-23, Dave Chinner <david at fromorbit.com> wrote:
> > That's a side effect of a minimal set of bug fixes that were needed
> > to avoid a load related log space hang. Those fixes disabled the
> > aild idling logic so the aild acts as a watchdog, so they wake up
> > every 50ms to check if there's anything to do. You'll find that
> > 3.0.x stable kernels have the same behaviour.
> >
> > The aild idling logic was re-enabled in mainstream kernels after the
> > root cause of the log space hangs was diagnosed and fixed, but I
> > can't see it ever being re-enabled in a CentOS 6.3 kernel....
> 
> Thanks for the clarification, Dave.  It sounds like I would need to
> either wait for this fix to hit the CentOS release kernel, or compile my
> own.

Do whatever you want - you might be waiting a while for CentOS to
fix it, though, because they don't fix user reported bugs. They just
repackage whatever Red Hat releases as RHEL.

TANSTAAFL.

> Do you know why I might not see this behavior on a different CentOS 6.x
> kernel?
> 
> Linux xxxxxx 2.6.32-279.5.2.el6.x86_64 #1 SMP Fri Aug 24 01:07:11 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux

Because the log hang bug hadn't been fixed in that kernel.

Cheers,

Dave.
-- 
Dave Chinner
david at fromorbit.com