Hard drive spindown

[Richard Hughes]

On Tue, 2005-10-11 at 14:23 +0200, Danny Kukawka wrote:
> On Monday 10 October 2005 21:54, Richard Hughes wrote:
> > One of the more frequent requests I'm being sent (as the maintainer for
> > gnome-power-manager) is the option to spindown the hard-drive after
> > about an hour or so of inactivity.
> >
> > Now more power stuff have been accepted into HAL, and the script stuff
> > has settled down, what about the patch I proposed:
> >
> > http://lists.freedesktop.org/archives/hal/2005-August/003107.html
> >
> > Worth reading is Danny's email:
> > ( http://lists.freedesktop.org/archives/hal/2005-August/003116.html )
> > about the spindown and spin-up real-world power savings of a typical
> > drive.
> > My laptop drives (nor my external USB2 drives) do not do their own PM,
> > and hence suck power when idle.
> 
> What kind of internal hardisk is in your laptop?

ICH4-M, ATA133.

>  IMO, you can't set 
> powermanagement for exteral USB harddisk, because you can't send the needed 
> commands over USB to the disk.

Yes, you're right here. Wouldn't work for me. :-(

> > Windows XP automatically spins them down after about an hour and a half
> > (by default).
> 
> IMO this does also not really work under windows. This option is activated on 
> my workstation and if I do nothing (no running programmes, only logged in, no 
> keyboard or mouse interaction) the harddisk is never spin down (only 
> sometimes in some mystic cases, but never when it should).

I know, mine is pretty random too.

> Anyway: If you use a journaling file system under linux you also need to 
> change the settings of the filesystem (commit interval, noatime ... see 
> laptop mode) and you should stop all reading/wrinting system daemons. Without 
> this changes this make no sense and the harddisk is spin-up again after some 
> minutes or seconds.

Valid point.

> As I sad in the othere mailthread, IMO this make no sense to touch the 
> harddisk settings. Did you ever tested this for you machine? How much battery 
> lifetime did you win? 

Been testing this for the last week or so.

And you're right, the difference is hardly noticeable. The biggest
saving was simply disabling the LCD brightness, the hdd power saving was
*minute* (assuming I left my laptop on all day whilst at uni, but then I
would have been better to suspend it...)

> > I'm not wanting to spin them down after 5 minutes, just a checkbox for
> > "[x] Spin down hard disk drives after one hour of inactivity"
> >
> > Or, does this functionality belong in the SetLowPowerMode script. Or,
> > should I leave this completely alone?
> 
> What mean SetLowPowerMode script? Why did you not call the laptop mode script 
> if you want to change the settings?

No, I think I agree with you now Danny (after doing tests myself), sorry
for being so persistent.

I will officially rm -f the hard-drive stuff from my local tree.

I'll also quote your mail and make up an entry on the g-p-m FAQ page to
refer people to.

Thanks,

Richard.