Re: [patch v7 0/21] sched: power aware scheduling

[Alex Shi <alex.shi@intel.com>]

On 04/16/2013 07:12 AM, Borislav Petkov wrote:
> On Mon, Apr 15, 2013 at 09:50:22PM +0800, Alex Shi wrote:
>> For fairness and total threads consideration, powersaving cost quit
>> similar energy on kbuild benchmark, and even better.
>>
>> 	    17348.850		    27400.458		   15973.776
>> 	    13737.493		    18487.248		   12167.816
> 
> Yeah, but those lines don't look good - powersaving needs more energy
> than performance.
> 
> And what is even crazier is that fixed 1.2 GHz case. I'd guess in
> the normal case those cores are at triple the freq. - i.e. somewhere
> around 3-4 GHz. And yet, 1.2 GHz eats almost *double* the power than
> performance and powersaving.

yes, the max freq is 2.7 GHZ, plus boost.
> 
> So for the x=8 and maybe even the x=16 case we're basically better off
> with performance.
> 
> Or could it be that the power measurements are not really that accurate
> and those numbers above are not really correct?

testing has a little variation, but the power data is quite accurate. I
may change to packing tasks per cpu capacity than current cpu weight.
that should has better power efficient value.

> 
> Hmm.
> 


-- 
Thanks Alex