> On Wed, 31 Jan 2001, Steve Lord wrote:
> > OK, I see what is going on here - and I think this could actually
> > break regular XFS as well - if you use the loop device on a highmem
> > machine. I will fix it in my 2.4.1 merge which should be out in cvs
> > in a day or two. 2.4.1 is running with XFS, but I am not happy with
> > what the kernel changes have done to performance.
> Could you please describe what performance problems are going on?
It is difficult to nail down the cause yet, but dbench has taken a
significant hit (40%). Single file (bonnie) is comparable with 2.4.0, the
dbench issue may be related to the throttling being placed on the
ll_rw_block interface by Jens' changes. The problem with working out
a bottleneck in dbench is it is such a random pile of stuff that
you really cannot point a finger at any one thing. I need to go
find some more deterministic measurements.
The performance drop off is not limited to xfs though ext2 appears
to suffer as well.