Re: Poor PostgreSQL scaling on Linux 2.6.25-rc5 (vs 2.6.22)

Ingo Molnar
2008-03-11T09:59:19Z

* Nick Piggin <nickpiggin@yahoo.com.au> wrote:

> > Just a quick suggestion, does a simple runtime tune like this fix
> > the workload:
> >
> > for N in /proc/sys/kernel/sched_domain/*/*/flags; do
> > echo $[`cat $N`|16] > N
> > done
> >
> > this sets SD_WAKE_IDLE for all the nodes in the scheduler domains
> > tree. (doing this results in over-agressive idle balancing - but if
> > this fixes your testcase it shows that we were balancing
> > under-agressively for this workload.) Thanks,
>
> It doesn't change anything.
>
> There is no idle time for this workload, btw.

oh, i thought you said that. Could you try to turn SD_WAKE_AFFINE
all-off and all-on perhaps, via the same scriptlet?

Ingo