powerd and increase in energy need

[Alexander Leidinger]

Quoting Luigi Rizzo <rizzo at iet.unipi.it> (from Wed, 21 Mar 2012  
18:37:28 +0100):

> I guess that the credit for power saving goes mostly to the CPU
> architects. Powerd only gives second-order savings, and C1 vs. C3
> is ineffective, at least for HZ=1000
>
>         CPU     Power (watts)
>         freq    idle    16 threads
>         -----------------------
>          200     48      51
>         2200     52      83
>         3200     54     115
>         3401     56     118
>
>         powerd   48     118

I hope you all don't use a cheap PSU, but a _good_ high efficient one,  
which really draws less power when idle instead of generating heat.  
Some PSUs are only efficient in a sweet spot, instead of being  
efficient over a broad range, even when being idle. See  
http://en.wikipedia.org/wiki/80_PLUS for a quick and not so in-deep  
overview (and the reality may differ from manufacturer to manufacturer).

Bye,
Alexander.

-- 
That does not compute.

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