Re: BFS vs. mainline scheduler benchmarks and measurements

[Martin Steigerwald]

Am Freitag 11 September 2009 schrieb Mat:
> Martin Steigerwald <Martin <at> lichtvoll.de> writes:
> > Am Donnerstag 10 September 2009 schrieb Ingo Molnar:
> 
> [snip]
> 
> > > what is /debug/sched_features - is NO_NEW_FAIR_SLEEPERS set? If not
> > > set yet then try it:
> > >
> > >   echo NO_NEW_FAIR_SLEEPERS > /debug/sched_features
> > >
> > > that too might make things more fluid.
> 
> Hi Martin,

Hi Mat,

> it made an tremendous difference which still has to be tested out :)

[...]

> Concerning that "NO_NEW_FAIR_SLEEPERS" switch - isn't it as easy as to
> 
> do the following ? (I'm not sure if there's supposed to be another
>  debug)
> 
> echo NO_NEW_FAIR_SLEEPERS > /sys/kernel/debug/sched_features
> 
> which after the change says:
> 
> cat /sys/kernel/debug/sched_features
> NO_NEW_FAIR_SLEEPERS NO_NORMALIZED_SLEEPER ADAPTIVE_GRAN WAKEUP_PREEMPT
> START_DEBIT AFFINE_WAKEUPS CACHE_HOT_BUDDY SYNC_WAKEUPS NO_HRTICK
>  NO_DOUBLE_TICK ASYM_GRAN LB_BIAS LB_WAKEUP_UPDATE ASYM_EFF_LOAD
>  NO_WAKEUP_OVERLAP LAST_BUDDY OWNER_SPIN
> 
> I hope that's the correct switch ^^

Thanks. Appears to work here nicely ;-). I thought this might be a debug 
fs that I need to mount separately, but its already there here. I will see 
how it works out.

I wondered whethere it might be a good idea to have a

echo default >  /sys/kernel/kernel-tuning-knob

that will reset it to the compiled in factory defaults. Would be a nice 
way to go back to safe settings again once you got carried away to far 
with trying those tuning knobs.

Ciao,
-- 
Martin 'Helios' Steigerwald - http://www.Lichtvoll.de
GPG: 03B0 0D6C 0040 0710 4AFA  B82F 991B EAAC A599 84C7

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