On Sun, 02 May 2010 16:27:28 +0200
Eric Dumazet [off-list ref] wrote:

C2 latency seems to be 64  (us ?), while C1 seems to be 1

the processor_idle module has a "latency_factor" module parameter.
The default is 2, but sometimes people think 6 is a better value...
.. any chance you can try that value ?

Also, I'm starting to wonder if Andi's patch to use io_schedule() needs
to be replaced with a net_schedule() kind of thing. The cpuidle code
currently has a weight factor for IO (based on measuring/experiments),
and maybe networking really needs another factor... so just having a
parallel concept with a different weight could be the right answer for
that.

Your CPU supports the following C-states : C1 C2 C3 
Your BIOS reports the following C-states : C1 C2 

C3 seems to be disabled in BIOS

btw this C2 == marketing name C3, and C3 == marketing name C6

(too many translations ;-)

we'll fix powertop to report the marketing name soon.


-- 
Arjan van de Ven 	Intel Open Source Technology Centre
For development, discussion and tips for power savings, 
visit http://www.lesswatts.org