Is the C3 possible with SMP?

Alexandre "Sunny" Kovalenko gaijin.k at
Mon Nov 3 04:23:34 PST 2008

On Mon, 2008-11-03 at 11:16 +0200, Alexander Motin wrote:
> Alexandre "Sunny" Kovalenko wrote:
> > When laptop is moving around with me, all USB modules are unloaded and I
> I will try to unload USB later today.
> > get about 4 hours of battery life with wireless on, admittedly on the
> > light usage (reading/writing E-mails, browsing web, typing up occasional
> > document). I consider this good for 4.4lbs (<2kg) laptop.
> I have a bit more then 3 hours at the same weight. Which CPU, video and
> chipset do you have?
This is CoreDuo T2400 with Intel 945GM video and Atheros 5212 a/b/g
wireless part. One other thing, I forgot to mention is: I set 

hw.pci.do_power_nodriver: 3

I have to be honest: I really do not know how much savings do I get from
which settings -- I merely went for most aggressive ones. YMMV.

> I have some doubts that C3 on only one of two cores could give much
> benefit. 
You are most likely right -- crude measurement by Kill-A-Watt shows 4%
difference which might as well be measurement error.

Alexandre "Sunny" Kovalenko (Олександр Коваленко)

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