[precise] unity 3d eats batteries for breakfast

[thom]

with unity 2d, my notebook draws 21.5 Watts with an estimated batterylife of 3.00 hours

with unity 3d, my notebook draws 45 Watts with an estimated batterylife of 1.15 hours

I have a hunch that this excessive powerdraw is a compiz "feature" but I dare to say that this might be a unwanted one on portable gear, making it even harder to crush bug #1

solution:

1) Compiz should have a low power mode as long as unity 3d is choice number one
(but, to be honest, i don't see that happening in the forseeable future actually)

2) I think it would be wise to push the developement of unity 2d more to the forground because it will prove to be the only viable choise on notebooks (regardless of 3D capability, unity 2D respects battery life). It would be sufficient at the moment to have the possibility to customize unity 2d as much as unity 3d (by use of MyUnity for instance) or at least some important subset of features (like the sizable icons).

3) automatic switching to unity 2d when on battery power (I think that this one will turn out to be rather difficult when logged in but easy at startup)

[Sebastien Bacher (seb128)]

Thank you for your bug report, what version of Unity do you use? Quite some issues have been addressed this cycle, see i.e
https://bugs.launchpad.net/ubuntu-power-consumption/+bug/917210

The difference between 3d and 2d should be minimal in precise, rather than focussing on how to change version you should perhaps focus on the bug you hit and getting that specific issue solved, it doesn't happen to everybody for sure

How do you measure the power use?

[thom (tsk)]

Hi Sebastien,

Version of Unity: 5.8.0-ubuntu2
https://bugs.launchpad.net/ubuntu-power-consumption/+bug/917210.......woops, that's a lot of traffic :-)

I'm not familiar with the underlying structure of both unity versions. As far as I know, unity 2d is written in Qt using a modified metacity and unity 3d is a compiz plugin. I would gladly go on bug-hunt if I knew where to start.

My measurements where not really fancy actually:
I have measured power use with an old school cross-coil power meter, and I timed with a clock how long the battery did approximately last on idle for both unity 2d and unity 3d under same conditions.

I was curious because the lifespan of the battery was incredibly shorter than under another well known OS.

I will read the posts on the link you send me.....possibly I will get some clues there...

Thanks for your reaction.

[thom (tsk)]

Sebastien, I think I found something,

with unity 3d I have an extra 60 processor wake-ups per second (stable, like a framerate) due to interrupt 18 (radeon HD3200 open driver)
on top of the more or less 60 regular wake-ups

with unity 2d I don't have these int18 wakeups at all, only the regular ones.

I think you hit the nail on the head....it looks exactly like:
https://bugs.launchpad.net/ubuntu-power-consumption/+bug/917210

I think that we can mark this bug as a duplicate

Thanks, and btw, you're good, you really know your stuff :-)