Slackware 14 (64-Bit Install) on laptop = Terrible battery life?

iiClouds · 10-29-2012, 10:56 AM

First post here. New to the forums. Linux novice.
I just installed Slack on to my laptop this morning while it was charging. I got the install and everything. Played around while it was charging. Now, I take my laptop off the charger and near 30 minutes later, the battery life is nearing 55%. Is battery life an issue with anyone else, or is it something I'm doing?

markush · 10-29-2012, 11:44 AM

Hello iiClouds, welcome to LQ and Slackware,

I have a subnotebook (Lenovo x100e, AMD, 2GB of RAM) with Slackware64-14 and the batterylife is more or less the same like with Windows 7 on the same computer.

Note that I have configured for low CPU-frequency (governor conservative), you'll find a tutorial here: http://docs.slackware.com/howtos:har...quency_scaling

But how about the batterylife on your laptop with Windows? Did you have another Linuxdistribution on the computer before you installed Slackware? And please tell us which Laptop you have (architecture, RAM etc.). Do the functionkeys work? can you configure the brightness of the screen (backlight)?

Markus

Mobile1 · 10-29-2012, 12:05 PM

I too have the same kind of results with battery life, it seems like there is no battery life. I have to run my laptop with AC plugged when using Slackware 14 - Windows I can run for a few hours before it drops to an unusable state.

TobiSGD · 10-29-2012, 12:29 PM

Would be nice to get some more infos:
- Which hardware are you using?
- Which drivers?
- Is the CPU frequency scaling configured and working?
- Do you have laptop-mode-tools installed and configured?

guanx · 10-29-2012, 03:49 PM

Actually pm-utils is doing things very well for me.

TobiSGD · 10-29-2012, 04:07 PM

pm-utils are a set of tools for setting your system to suspend or hibernate. How does that prevent the battery from draining if the system is running?

D1ver · 10-29-2012, 04:59 PM

I have a Toshiba z830 running 14.0 at the moment. Under windows it was getting ~5 hours battery life. With a stock Slackware install I would get ~3 hours battery life. Luckily however, I found this page at the linux laptop wiki. Adding the following lines to my lilo kernel boot parameters gives me 5-6 hours battery life in Slackware depending on how aggressive I am with screen brightness.

Code:

append="acpi_osi=Linux acpi_backlight=vendor pcie_aspm=force i915.i915_enable_rc6=1 i915.lvds_downclock=1 elevator=noop vt.default_utf8=0"

guanx · 10-29-2012, 05:21 PM

Quote:

Originally Posted by TobiSGD

pm-utils are a set of tools for setting your system to suspend or hibernate. How does that prevent the battery from draining if the system is running?

Code:

$ grep power.d /var/log/packages/pm-utils-*
etc/pm/power.d/
usr/lib/pm-utils/power.d/
usr/lib/pm-utils/power.d/pcie_aspm
usr/lib/pm-utils/power.d/hal-cd-polling
usr/lib/pm-utils/power.d/xfs_buffer
usr/lib/pm-utils/power.d/intel-audio-powersave
usr/lib/pm-utils/power.d/harddrive
usr/lib/pm-utils/power.d/sched-powersave
usr/lib/pm-utils/power.d/journal-commit
usr/lib/pm-utils/power.d/laptop-mode
usr/lib/pm-utils/power.d/wireless
usr/lib/pm-utils/power.d/readahead
usr/lib/pm-utils/power.d/disable_wol
usr/lib/pm-utils/power.d/sata_alpm

jtsn · 10-29-2012, 07:40 PM

Quote:

Originally Posted by iiClouds

First post here. New to the forums. Linux novice.
I just installed Slack on to my laptop this morning while it was charging. I got the install and everything. Played around while it was charging. Now, I take my laptop off the charger and near 30 minutes later, the battery life is nearing 55%. Is battery life an issue with anyone else, or is it something I'm doing?

It's a known issue. Not in Slackware, but in Linux. You usually get about 50 % of the battery life of the pre-installed OS. By fiddling around with powertop and laptop-mode-tools you can get it up to about 70-80 %, if you are lucky.

Use BattStat on the pre-installed OS to look for the time/wattage you are aiming for, then compare the readouts of powertop to it.

piratesmack · 10-29-2012, 08:25 PM

It's going to depend on what hardware/drivers you're using, but on my Intel Core i3 (Sandybridge) laptop with Intel HD 3000 graphics I get a couple more hours of battery life after applying these tweaks:
http://www.phoronix.com/scan.php?pag...15_power&num=1

Now I get around 5-6 hours in Slackware64 14.0, which is the same as I got in Windows.

iiClouds · 10-29-2012, 10:39 PM

My battery life while doing the same stuff in Windows is usually about 2 and a half hours. I'm going to try setting the governor to something different. I'll report back tomorrow with what I get.

kite · 10-29-2012, 11:17 PM

My setup:

MacBook Pro 8,1 + mountain lion os: about 6 hours
MacBook Pro 8,1 + Slackware 14.0 x86_64: about 3 hours after tweaks to save some power.

Not satisfied for the battery life under slackware!

kite · 10-30-2012, 12:03 AM

Quote:

Originally Posted by D1ver

I have a Toshiba z830 running 14.0 at the moment. Under windows it was getting ~5 hours battery life. With a stock Slackware install I would get ~3 hours battery life. Luckily however, I found this page at the linux laptop wiki. Adding the following lines to my lilo kernel boot parameters gives me 5-6 hours battery life in Slackware depending on how aggressive I am with screen brightness.

Code:

append="acpi_osi=Linux acpi_backlight=vendor pcie_aspm=force i915.i915_enable_rc6=1 i915.lvds_downclock=1 elevator=noop vt.default_utf8=0"

I just tried your approach because my system has i5 cpu/gpu, it helps a lot. XFCE reported one hour more battery life. I have about 4 hours and 20 minutes battery life!!!

D1ver · 10-30-2012, 02:12 AM

Quote:

Originally Posted by kite

I just tried your approach because my system has i5 cpu/gpu, it helps a lot. XFCE reported one hour more battery life. I have about 4 hours and 20 minutes battery life!!!

Glad to help

There is a little bit of info on some of the options in the Phoronix link that Piratesmack linked. I think they're all pretty harmless, I haven't noticed any negative efftects, only a doubling in battery life heh..

TobiSGD · 10-30-2012, 04:51 AM

Keep in mind that a bad battery life can also be caused by using the free drivers if you have a AMD/ATI or Nvidia videochip in your notebook.