Re: Battery life difference

[Tino Keitel]

On Mon, Jul 07, 2008 at 11:48:42 +0200, Filippo Zangheri wrote:
> On 06/07/2008 19:21, Tino Keitel wrote:
> > On Sat, Jul 05, 2008 at 18:44:21 +0300, Felipe Balbi wrote:
> >> Hi,
> >>
> >> On Sat, Jul 5, 2008 at 6:23 PM, Arjan van de Ven <arjan@xxxxxxxxxxxxx> wrote:
> > 
> > [...]
> > 
> >>> Also take a look at
> >>> http://kerneltrap.org/mailarchive/linux-kernel/2008/5/8/1771024 because
> >>> these patches save like 0.75W in our lab.
> >> cool, is it merged upstream ?
> > 
> > If I got this right, at least Linux 2.6.25 allows to control this via
> > "/sys/class/scsi_host/host*/link_power_management_policy". Setting it
> > to "min_power" does the trick. This is also covered by powertop 1.10
> > and later.
> 
> I cannot see this on 2.6.25.9. Is there a particular configuration option
> you must enable, or it just didn't make it to 2.6.25?

All I can say is that I see it with 2.6.25.9 on a Thinkpad X61s with SATA
set to AHCI. See commit ca77329fb713b7fea6a307068e0dd0248e7aa640 for
details.

Regards,
Tino
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/