Re: [RFC] sleepy linux

[H. Peter Anvin]

Pavel Machek wrote:
> On Wed 2007-12-26 12:43:56, H. Peter Anvin wrote:
> > Oliver Neukum wrote:
> > > Am Mittwoch, 26. Dezember 2007 19:56:59 schrieb H. Peter Anvin:
> > > > > 3) Network card that is either down
> > > > >    or can wake up system on any packet (and not loose too many packets)
> > > > This is the big crux I see.  You're going to constantly wake up the 
> > > > machine due to broadcast packets, and spend a lot of power just going in 
> > > > and out of S3.
> > > How many machines care a lot about saving power while they are connected
> > > to an ethernet? Wlan might be more of a problem.
> > A lot of them should.  An inordinate amount of machines sit there burning 
> > power for no reason.  You can argue that S3 isn't needed -- that nohz + 
> > C3/C4 + turning off the screen would be enough, and that might be
> > + legit.  
>
> NOHZ + C4 + turn off screen + turn off disk + turn off SATA is still
> ~8W on thinkpad x60.
>
> S3 is ~1W.
>
> That's quite significant difference.
>
> (But yes, connected-to-ethernet is not most important use scenario.)
> 								Pavel

Still... if we could get the desktops of the world down anywhere close 
to that range when not used, it would be a huge win.

	-hpa
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