On Thu, 2003-06-19 at 10:28, Steven Pratt wrote:
> Steve Lord wrote:
>
> >On Thu, 2003-06-19 at 09:31, Steven Pratt wrote:
> >
> >
> >>While trying to do performance regression testing on 2.5.xx kernels, we
> >>are seeing hangs when runnuing xfs with 16 clients quite often. No
> >>error messages, just that dbench does not complete. XFS is hte only
> >>filesystem the causes this behavior with dbench, It is very
> >>reproducibly on the 2.5.7x kernels. Has anyone else seen this? What
> >>kind of debug information would you need.
> >>
> >>Steve
> >>
> >>
> >
> >Hi Steve,
> >
> >Is this the performance regression tests which get run on 2.5 kernels?
> >I have seen the results, never a comment about hangs before.
> >
> Yes, this is the nightly regression runs that we have been doing on the
> 2.5 kernel series. We have been more worried about changes in
> performance than functional issues to this point (that is our mission),
> Since I am running multiple runs of dbench and averaging results, having
> one run die still allows us to get numbers. I just looked over the
> results again and I see problem both on single client and on 16 client
> runs. I seem to remember that we have problem more often on 64 client
> runs but dropped that version for lack of runtime. Should also not that
> this may not be as reproducible as I first mentioned, seems more like 1
> out of 8 runs or so dies.
OK, I have dbench 16 running in a loop here, if it keeps going for
a couple of hours I will send you a diff from 2.5.72 and we can see
if it fixes things for you. I will try a second box with a vanilla
Linus kernel and see if I can hit it there. So far no hangs, but there
do seem to be temporary stalls occasionally which is odd.
>
> >Unfortunately, we have been somewhat tied up with 2.4 things and
> >2.5 is not getting as much air time - and kdb does not work which
> >makes debugging much more interesting. Let me try it out and see
> >what happens, and details about the setup you see this in would
> >be appreciated.
> >
> Understand about 2.5 work. Here is a link to the test machine setup
> information.
> http://ltcperf.ncsa.uiuc.edu/data/2.5.71/2.4.20-vs-2.5.71/HardwareSoftware.html
>
Hmm, I don't have 8 cpus in all the boxes I can use for this right now,
never mind 8 cpus in each!
Steve
--
Steve Lord voice: +1-651-683-3511
Principal Engineer, Filesystem Software email: lord@xxxxxxx
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