powerd adaptive mode latching

Daniel O'Connor doconnor at gsoft.com.au
Thu Jan 17 19:38:03 PST 2008


On Thu, 17 Jan 2008, Dag-Erling Smørgrav wrote:
> "Daniel O'Connor" <doconnor at gsoft.com.au> writes:
> > One problem with it is that it lags behind actual usage by a few
> > seconds (presumably averaging it).
>
> It is based on the (didle/dt) / (dtotal/dt) fraction computed from
> kern.cp_time, which can take a while to ramp up.  This is not easily
> seen in a cursory reading of the code, as the fraction is computed in
> a very roundabout way.

I meant the current usage reported by ACPI.
Presumably totally up to the BIOS implementation as to how it works..

> > Turning the LCD off saves about 4W too.
>
> Hmm, it would be interesting to experiment with varying backlight
> brightness based on system load :)

Heh, sounds like a great way to get a headache 8-)

-- 
Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
"The nice thing about standards is that there
are so many of them to choose from."
  -- Andrew Tanenbaum
GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 187 bytes
Desc: This is a digitally signed message part.
Url : http://lists.freebsd.org/pipermail/freebsd-current/attachments/20080118/5eb10c22/attachment.pgp


More information about the freebsd-current mailing list