Re: [RFC] sleepy linux

Pavel Machek
2007-12-26T20:51:03Z

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
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