HORRIBLE 11.10 battery life - fix anytime soon?

[fictivetoast]

I updated from 11.04 to 11.10 earlier this week, and though I'd heard reports of increased power usage on oneric, this is crazy.

I have a relatively new Lenovo x220 (core i7) with a 9-cell battery. With screen dimmed a bit and intermittent wifi use under Windows 7 I can easily get 8+ hours (and could push it to 12+ using Lenovo's power-usage tweaks). On Ubuntu 11.04 I still got a decently respectable 6+ hours. On Oneric, I'm getting around 4 hours with wifi turned off - that's a third of the battery life I can get on Windows. This is unacceptable.

What the heck is going on? I've heard this is somewhat kernel related, but even so, this seems insane to me. I've been on Ubuntu for six years and hate the prospect of having to turn back to Windows. I opted for this laptop specifically for the battery life, and the insane power consumption is making 11.10 practically useless for me. I'm tempted to revert all the way to 10.10 to see if I can at least get 7 hours with gnome2 and an older kernel.

Can we expect a fix anytime soon? Have the developers publicly commented on this? Is it even being acknowledged? Given how much of a mobile emphasis Ubuntu has had in recent years (netbook edition etc), it seems like they're shooting themselves in the foot releasing a distro that throws portability out the window.


(Relatedly, did something change in powertop? In previous Ubuntu releases, the stock powertop available in the repos would give me a useful realtime power consumption report along with an estimate of how much juice was left - the powertop on 11.10 seems to offer a bunch of confusing separate tabs with very little useful information.)

[3Miro]

This is what I am using on 11.10 to get extra battery life (it gies me about an hour extra on my 6-cell battery).

http://www.webupd8.org/2011/09/jupit...lable-for.html

The kernel related thing is largely a FUD, there are some laptops BIOS chips that don't conform properly to standards and cause some issues. This is not a problem with the kernel.

Your regression is probably due either to a rogue process taking over the CPU or just some settings that need to be adjusted. Double-check Gnome power manager as well, some of the defaults may have changed due to the upgrade to Gnome 3.

[fictivetoast]

This is what I am using on 11.10 to get extra battery life (it gies me about an hour extra on my 6-cell battery).

http://www.webupd8.org/2011/09/jupit...lable-for.html

The kernel related thing is largely a FUD, there are some laptops BIOS chips that don't conform properly to standards and cause some issues. This is not a problem with the kernel.

Your regression is probably due either to a rogue process taking over the CPU or just some settings that need to be adjusted. Double-check Gnome power manager as well, some of the defaults may have changed due to the upgrade to Gnome 3.

Thanks for the Jupiter tip, but the only function it seems to offer is manually selecting the "power saver" performance mode, which I'd think my computer already hopped into automatically when I unplugged it, no ? In any event, even with Jupiter my battery gauge is still reading 4:30 remaining when I immediately unplug and have a full charge.

As for "gnome power manager" are you referring to the power manager settings in the control panel? Cause the only options available there are when to dim the screen, and when to suspend or hibernate the system.

And on runaway processes, in system monitor my current process are currently hovering around :
plugin-container : 32% (ie the flash plugin)
Gnome-System-Monitor : 16%
Firefox : 12%
compiz : 4%
everything below there is at 0%, and in general all 4 of my cpu cores are hovering between 10% and 40%, never above.

[3Miro]

Jupiter gives you much better "powersave" settings than the default ones.

Stop flash and let FF open with only basic pages (i.e. like Ubuntu forums). Then see how much time you have, you may have to wait a couple of minutes to get an accurate reading. Flash under Linux will eat your battery pretty quickly. The 33% that you are seeing means that one (out of 4) cores is running on full power to keep up with flash.

Another thing that I have noticed is that the battery applet is very sensitive to the instantaneous load of the system. Let the battery indicator show the time on the top bar and let it run for a while to get a better estimate on a long run.

[alfefried]

+1

Well, shut down your computer and see how much battery life you get

I noticed such a default on my hp probook 4530, with i5, when installing 11.10.
It looks like it's getting worse and worse at each new version, and i agree, this is not acceptable: poor battery life and unbearable fan noise !

There must be a kernel issue, you can vote for it to promote a fix :

https://bugs.launchpad.net/ubuntu/+s...ux/+bug/818830
https://bugs.launchpad.net/ubuntu/+s...ux/+bug/834037
https://bugs.launchpad.net/ubuntu/+s...ux/+bug/760131

you should track some threads here, for example:
http://ubuntuforums.org/showthread.p...822629&page=14

on post #23, i used the trick of "i915.i915_enable_rc6=1", that improved a bit the problem.

Did you have better performances using lucid ?

[fictivetoast]

I spoke too soon, Jupiter is indeed helping - I seem to be bumped up to ~6h30m now. Again though, that's still half what Windows 7 offers. FYI I've applied this fix to at least keep my core temps down.

I'll keep my eye on that kernel thread for now I suppose.

[techvish81]

i installed jupiter eepc support package and jupiter indicator through synaptic, but i cant open it or see its settings, there is some difference in battery consumption but i'm not able to figure out as it is to early to tell, can anyone give me a way to see the settings mentioned in above posts in jupiter.

[aeronutt]

FYI, this significantly decreased power draw on my i3 based laptop.

http://ubuntuforums.org/showpost.php...78&postcount=9

My current draw went from ~1500mA to ~800mA with the following kernel options

change
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
To
GRUB_CMDLINE_LINUX_DEFAULT="i915.i915_enable_rc6=1 i915.i915_enable_fbc=1 i915.lvds_downclock=1"

then sudo update-grub

The one that made the majority (nearly all) of the difference was the first.

[alfefried]

yeah,

i was looking for this thread too :
http://ubuntuforums.org/showthread.php?t=1865820

there weren't the i915.lvds_downclock=1 there ...

Does anyone understand what it means ?



edit: found http://www.lesswatts.org/projects/powertop/faq.php , that may be interesting to us.

[fictivetoast]

I've managed to bump it up to an estimated 9+ hours with screen around 70% brightness and wifi/bluetooth both on by adding those additional parameters to my grub conf, which now reads :

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash pcie_aspm=force i915.i915_enable_rc6=1 i915.i915_enable_fbc=1 i915.lvds_downclock=1"

Woohoo!!!