Re: [Announce] [patch] Modular Scheduler Core and Completely Fair Scheduler [CFS]

Nick Piggin
2007-04-17T11:12:20Z

On Tue, Apr 17, 2007 at 11:59:00AM +0200, Ingo Molnar wrote:
>
> * Nick Piggin <npiggin@suse.de> wrote:
>
> > 2.6.21-rc7-cfs-v2
> > 534.80user 30.92system 2:23.64elapsed 393%CPU
> > 534.75user 31.01system 2:23.70elapsed 393%CPU
> > 534.66user 31.07system 2:23.76elapsed 393%CPU
> > 534.56user 30.91system 2:23.76elapsed 393%CPU
> > 534.66user 31.07system 2:23.67elapsed 393%CPU
> > 535.43user 30.62system 2:23.72elapsed 393%CPU
>
> Thanks for testing this! Could you please try this also with:
>
> echo 100000000 > /proc/sys/kernel/sched_granularity
>
> on the same system, so that we can get a complete set of numbers? Just
> to make sure that lowering the preemption frequency indeed has the
> expected result of moving kernbench numbers back to mainline levels. (if
> not then that would indicate some CFS buglet)
>
> could you maybe even try a more extreme setting of:
>
> echo 500000000 > /proc/sys/kernel/sched_granularity
>
> for kicks? This would allow us to see how much kernbench we lose due to
> preemption granularity. Thanks!

Yeah but I just powered down the test-box, so I'll have to get onto
that tomorrow.