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

From: Pavel Machek
Date: Sat Jul 30 2005 - 14:54:57 EST


Hi!

> > > What kind of results do you get with a more realistic setup, like
> > > running KDE or Gnome OOTB?
> > >
> >
> > Here are results with KDE running.
> >
> > - no peripherals attached, i.e. truly mobile setup.
> > - all modules loaded
> > - klaptopdaemon disabled in order to eliminate competition in polling the
> > already slow battery controller
> > - furthermore, I found that artsd prevents entering C3 and generally
> > increases power consumption (ALSA, snd_intel8x0)
> > - voltage is 16.5V
>
> > HZ=100: HZ=1000: DIFF:
> >
> > 1) averages:
> >
> > backlight off, arstd off:
> > 637.17 679.67 42.5
>
> > backlight off, artsd on:
> > 799.46 806.13 6.67
>
> So it looks like artsd wastes way more power DMAing a bunch of silent
> pages to the sound card than HZ=1000.
>
> There's nothing the ALSA layer can do about this, it's a KDE bug.
>
> I think this is a good argument for leaving HZ at 1000 until some of
> these userspace bugs are fixed.

WTF? HZ=1000 eats energy like crazy. artsd eats energy like crazy. And
you advocate breaking kernel because artsd is broken?!
Pavel
--
if you have sharp zaurus hardware you don't need... you know my address
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