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

Hans Kristian Rosbach
2005-08-04T12:47:57Z

On Wed, 2005-08-03 at 08:57 -0500, Dmitry Torokhov wrote:
> On 8/3/05, Hans Kristian Rosbach <hans.kristian@isphuset.no> wrote:
> > On Tue, 2005-08-02 at 00:50 -0400, James Bruce wrote:
> > > Theodore Ts'o wrote:
> > > > 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
> > > ^^^^^^^^
> > >
> > > > 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.
> > >
> > > Yes, laptops are mostly PS/2, which is why I only claimed a statistic
> > > for desktops. Desktops pretty much all use USB mice now. If 250Hz were
> > > only being sold as an option for laptops, we could leave it at that, yet
> > > its being pushed as a default that's "good for everyone". For desktops
> > > this is not currently true at all. By the time USB is fixed to do power
> > > saving, we'll probably have a working tick-skipping patch which makes
> > > the whole HZ argument moot.
> >
> > Most new laptops are moving away from PS/2 ports, for example my
> > shining (literally) new Acer Ferrari 4005 only has USB2 ports for mice
> > and keyboard inputs (unless in the optional pcie docking station maybe).
> > So my suggestion would be to fix USB power management.
> >
>
> You are talking about external ports. I am pretty sure that installed
> keyboard and touchpad (or whattever pointing device it has) are plain
> old PS/2.

Well, yes..

But as I _never_ use the touchpad, it is quite necessary to keep USB
enabled for me at any time as an external PS2 mouse is not possible.

-HK