[ltp] what to use to save battery

[Martin Lorenz]

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On Thu, Sep 07, 2006 at 11:23:45AM +0800, Kelvin KAN wrote:
> And the larger the amount of memory, the more the energy consumed to=20
> write them all to disk.
>=20
> Because someone earlier mentioned to increase the amount of memory (RAM)=
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> to conserve disk activities.
>=20
> I just tried to point out that if you use hibern/restore a lot (write to=
=20
> disk), the energy consumption would increase, contradiciting the purpose.

I made the experience (with my former notebook) that suspend2 improves
matters, because it saves and restores a lot faster than the native suspend
code.

I haven't tried it with my X60s yet, because there are some more issues to
be fixed beforehand...

I agree, that hibernating (aka suspend-to-disk) is not for short periods
because it will consume more power on suspend/resume than it saves by
switching off copletely inbetween.

I'd say (from experinece - not really proofed) for up to 30 minutes STR will
be cheaper than STD with swsusp2 - for 1 GB of memory. for the mainstream=
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swsusp it might be like 45 minutes because of the slower save/restore.
if you have, say, 512 MB RAM you probably can take 30% off the above
numbers. the scale is IMHO not linear.

so far from my experience

>=20
>=20
> Andrew Barr wrote:
>=20
> >On Wed, 2006-09-06 at 15:59 -0400, Brad Langhorst wrote:
> >
> >>On Tue, 2006-09-05 at 11:58 +0200, Adrian Bastholm wrote:
> >>
> >>>I was under the impression that hibernation saves the state to disk,
> >>>and a suspend consumes power since the state is saved to RAM.
> >>>
> >>you're correct.
> >>
> >>sometimes people use hibernate as a generic term.
> >>
> >
> >The original point (no longer quoted), I think, was to point out that
> >hibernate does a lot of disk I/O and consumes more immediate power than
> >STR for short periods.
> >
> >
> >>brad
> >>
> >>
> --=20
> The linux-thinkpad mailing list home page is at:
> http://mailman.linux-thinkpad.org/mailman/listinfo/linux-thinkpad

gruss
  mlo
- --
Dipl.-Ing. Martin Lorenz

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