Re: Battery life difference

From: Felipe Balbi
Date: Sat Jul 05 2008 - 10:00:39 EST


Hi,

On Sat, Jul 5, 2008 at 4:36 PM, Theodore Tso <tytso@xxxxxxx> wrote:
> You didn't say which battery you are using; I'm guessing you are using
> the 4 cell slim-line battery, which is rated at 28.8 Watt-hours?

yeah, the normal slim-battery.

> How many Watts is Powertop reporting that you are using? I'm down to

eheh, it's only 15.5w :-p

> around 8-9 watts, and around 9.5 watts in "airplane mail reading mail"
> (wireless disabled, USB modules unloaded, screen brightness turned way
> down, laptop_mode enabled, all mail messages pulled into memory, and
> reading/deleting mail using mutt, a character-mode based mail reader
> --- if you use Evolution, your energy usage will definitely be higher :-).

no crappy evolution, I use fluxbox and mutt. This ubuntu machine is
for testing purposes only :-p

Anyways, it's bad that we have to manually unload several modules,
specially usb. I'm sure windows reaches 9 watts consumption without
breaking functionality. And that's the big thing. I think that's something
we should be aiming. Dontcha think?

> See http://thunk.org/tytso/blog/2007/10/29/tip-o-the-hat-wag-o-the-finger-linux-power-savings-for-laptop-users/

Good article, but still. On the end user point of view, it's difficult to do
rmmod/insmod operations. Recently I sent a patch to the bluez team
adding a checkbox to bluetooth-properties that would send the SetMode("off")
dbus message (which is the same as running hciconfig hci0 down).

That helps a bit, but still the driver is not been used and keeps generating
wakeup events. Why if it's not been used ?

Maybe this is something we should start thinking about, right ?

--
Best Regards,

Felipe Balbi
felipebalbi@xxxxxxxxxxxxxxxxxxxxx
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