Re: Power consumption HZ100, HZ250, HZ1000: new numbers

ambx1
2005-08-03T15:21:55Z

----- Original Message -----
From: Theodore Ts'o <tytso@mit.edu>
Date: Monday, August 1, 2005 4:42 pm
Subject: Re: Power consumption HZ100, HZ250, HZ1000: new numbers

> On Mon, Aug 01, 2005 at 12:18:18PM -0400, James Bruce wrote:
> >
> > The tradeoff is a realistic 4.4% power savings vs a 300% increase
> in the
> > minimum sleep period. A user will see zero power savings if they
> have a
> > USB mouse (probably 99% of desktops). On top of that, we can
> throw in
> > Con's disturbing AV benchmark results (1). As a result, some of
> us
> > don't think 250HZ is a great tradeoff to make
> _for_the_default_value_.
> Most laptops (including mine, a Thinkpad T40) use a PS/2 mouse. So in
> the places where power consumption savins matters most, it's usually
> quite possible to function without needing any USB devices. The 90%
> figure isn't at all right; in fact, it may be that over 90% of the
> laptops still use PS/2 mice and keyboards.
>
> - Ted

Also, my understanding was that when we properly support usb suspend,
this won't be an issue anyway for much usb hardware. I think it's
possible to put some mice to sleep when there isn't any motion and
then wakeup later.

4.4% savings may not be much, but these things do add up. For a
laptop's workload, I think this is worth it.

Thanks,
Adam