[ltp] Battery discharge during hibernation

[Micha Feigin]

On Tue, 10 Mar 2009 16:27:21 +0100
Thomas Kahle <tom111@gmx.de> wrote:

> Anton Katsarov wrote:
> > Hi, all,
> >=20
> > I have a ThinkPad T400 and I am using pm-hibernate with the script for
> > stopping one of the CPU cores.
> >=20
> > Last night I hibernated my computer and the batter was 82% charged. I
> > plugged out the AC. Today when I turned it on again it was 75% charged.
> > And that is not the first time I face this issue.
> >=20
> > Is it possible during hibernation the battery to be discharged? Does
> > anyone have the same issue?
>=20
> Hi,
>=20
> I had the same problem and people started to call me a crazy paranoid...
> But it was not related to Wake on LAN. On my X61s
>=20
> echo =E2=80=9Cshutdown=E2=80=9D > /sys/power/disk
>=20
> solved the problem. You have to repeat this step after every reboot (or
> was it after every sleep even.) So you should place a hook in your
> hibernate tools and boot process.
>=20
> Somehow, if this is set to 'platform' I think the RAM will stay on to
> make a hybrid sleep mode known from Apple's laptops. The computer does
> suspend to RAM and Disk at the same time to come up very fast, but not
> crash if running out of battery during sleep.
>=20

As far as I understand the documentation platform is acpi s4. s5 is a compl=
ete
shutdown without the system knowing that it is going into suspend. s4 is so=
me
bios supported suspend. should probably be nicer on the system on wake up.
Don't know the exact specifics though.

Another thing that may be staying on BTW except the lan is usb power. I have
some bios options regarding usb power when the machine is off, don't rememb=
er
the specifics, but maybe you enabled keeping the usb powered up. Try connec=
ting
something that powers from the usb (not sure if an optical mouse is enough =
or
whether an mp3 that charges from the usb or seemilar junk is needed)

> hope to help
> Tom
>=20
> >=20
> > Best regards,
> > Anton Katsarov=20
>=20
>=20