Re: [PATCH 8/15] sched: Add parameter sched_mn_power_savings tocontrol MN domain sched policy

From: Vaidyanathan Srinivasan
Date: Mon Aug 24 2009 - 11:33:24 EST


* Peter Zijlstra <peterz@xxxxxxxxxxxxx> [2009-08-24 16:56:18]:

> On Thu, 2009-08-20 at 15:39 +0200, Andreas Herrmann wrote:
> > Signed-off-by: Andreas Herrmann <andreas.herrmann3@xxxxxxx>
> > ---
>
> > +#ifdef CONFIG_SCHED_MN
> > + if (!err && mc_capable())
> > + err = sysfs_create_file(&cls->kset.kobj,
> > + &attr_sched_mn_power_savings.attr);
> > +#endif
>
> *sigh* another crappy sysfs file
>
> Guys, can't we come up with anything better than sched_*_power_saving=n?
>
> This configuration space is _way_ too large, and now it gets even
> crazier.

Hi Peter and Andreas,

Actually we had sched_power_savings and related simplifications, but
that did not really simplify the interface.

As for this mulit-node MN stuff, Gautham had posted a better solution
to propagate the sched_mc flags without need for new sysfs file and
related changes.

Please take a look at: http://lkml.org/lkml/2009/3/31/137 and
http://lkml.org/lkml/2009/3/31/142 which actually degenerates the
domain.

However Andreas's requirement seem to indicate multiple nodes within
a single socket. I did not yet completely understand that topology.
Some for of smart degeneration may save an additional tunable here.

Thanks for pointing me to this patch.

--Vaidy
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/