Power-Mgt (Was: Re: cvs commit: src/sys/i386/cpufreq est.c )

[Bjoern A. Zeeb]

On Mon, 17 Mar 2008, Poul-Henning Kamp wrote:

Hi,

> [Moved to arch@]
>
> In general, I think we must make power-aware computing our "next
> SMPng project", not in the sense of delaying the next major release
> five years, but in the sense that power consumption should permerate
> our thinking about the operating system from now on.
>
> Overall, I think that means that we should:
>
> *  Enable performance neutral power savings on servers
> 	- spin down unused disks. (geom/drivers)
> 	- use only as many CPU cores as necessary (scheduler)
> 	- light cpu-throttling.
> 	- downgrading 1GB to 100MB ether when idle.
>
> *  Aim to meet or execeed energystar 4.0/5.0[1] on desktops and
>   plugged laptops.
> 	- Pretty much as above, but with specific targets.
> 	- http://www.energystar.gov/index.cfm?c=revisions.computer_spec
>
> *  Be as battery-frugal as possible on battery driven laptops.
> 	- Any trick in and off the book.

so while this topic is one,

what actually happens to an unrecognized card or a card with no driver
loaded currently? How much power does an unsued card use and can we do
anything about that? Are we perhaps already doing something about
that?


/bz

-- 
Bjoern A. Zeeb                                 bzeeb at Zabbadoz dot NeT
Software is harder than hardware  so better get it right the first time.