Re: dynamic-hz

[Pavel Machek]

Hi!

> > > Lets take an example.  Lets say that:
> > > * a CPU runs at about 245mA when active
> > > * 90mA when inactive
> > > * the timer interrupt takes 2us to execute 1000 times a second
> > > * no other processing is occuring
> > 
> > Now take a real laptop and the numbers are in the 20W (15A) range.
> 
> Roughly 650mA for my laptop while idle or just under 7W - by calculation
> from battery capacity and measured lifetime.  The question is how much
> of that is due to the CPU itself and how much is due to the
> peripherals.

On Arima notebook here, whole machine takes 28W on 800MHz, idle
(measured using external power meter), 33W with max backlight, and 68W
at 2GHz, computing. Going to HZ=100 makes it one Watt less. I'd say
that's quite significant. [17W number was based on internal power
meter when running on battery].

So yes, CPU *is* taking more than all other perihepals.
								Pavel
-- 
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