From: Laurent Giroud <laurent.giroud_at_libertysurf.fr>
Date: Fri, 16 Apr 2004 14:31:04 +0200

> The cpu load and the disk-on-time can be related. Imagine the cpu is very
> busy with scrolling, bitswapping and meter peeking while it also must fill
> the mp3 buffer from disk. Then the time it takes to fill the mp3 buffer is
> longer than it would be when the cpu didn't have to do anything else. Thus a
> busy cpu can mean that the disk stays turned on for a longer period. That
> may be a more significant power drain than the power the cpu itself
> consumes.

Could'nt a priority system be used which would ensure hard disk related CPU code would be prioritary over other kind of code ?
(it might already be the case but I'm not an expert at all so I'm just asking)

> Still I don't expect much of it because it's the spinup that is the worst
> power eater.

I wonder if there's a way to have the disk spinup at a slower rate than usual ?
I guess that energy consumption is related to the acceleration rate during the spinup phase, so spinning up at a slower rate might help save a few watts (just a guess, don't beat me if that's plain dumb).
It seems quite unprobable that disks have a "slow spinup" mode, but once again, I'm ignorant in this field so it doesn't cost a lot to ask ;)

Regards,
Laurent
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Received on 2004-04-16