[OpenAFS] Re: Expected performance

Andrew Deason adeason@sinenomine.net
Fri, 20 May 2011 14:10:35 -0500

On Fri, 20 May 2011 13:51:05 -0400 (EDT)
Andy Cobaugh <phalenor@gmail.com> wrote:

> > ...or it's that you're writing to the same disk twice as much. If the
> > cache and /vicepX are on the same disk, it seems pretty intuitive that
> > it's going to be slower.
> It was with memcache.

Well _I_ wasn't talking about memcache. :)

> mal and badger are slightly different hardware, but the tests above
> show that we get very similar performance between all server and
> client combinations except the case where client and server are on the
> same machine.
> Maybe I'm missing something here?

I think to some extent it can still be that they're just using the same
hardware resources, so some performance loss is to be expected (if the
network wasn't the bottleneck for separate machines). I'm not sure if
that can explain that degree of difference, though. I believe Rx in the
past has had some odd behavior that really low RTT, but any known fixes
there should have been in 1.6 for awhile.

I expect a similar thing happens on 1.4? Though of course the baseline
performance is probably different, so it's not really comparing the same

Andrew Deason