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

[Ingo Molnar]

* Nick Piggin <nickpiggin@xxxxxxxxxxxx> 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
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