Messages in this thread | | | Date | Mon, 7 Jul 2008 23:37:25 +0200 | From | Tino Keitel <> | Subject | Re: Battery life difference |
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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@infradead.org> 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
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