xfs-trace-ilock-more

[Christoph Hellwig]

On Wed, Dec 14, 2011 at 02:24:32PM -0500, Jeff Mahoney wrote:
> That's pretty much the explanation. With heavy reader load, buffered
> writes were stalling for 80 ms and sometimes longer. I suspected it
> was contention on the ilock and the tracing with that patch
> demonstrated a delay there. Since we were chasing a similar issue at
> another site, it seemed worthwhile to just keep it around. We're still
> tracking down the cause. I'm not sure if more recent kernels have the
> same issue as there's been quite a lot of churn.

Ok.  I was a bit surprised that it was one out of only two XFS updates
that went into a recent SLES security errata, and I never heard about it
before.