Arch Linux

fusionlord

Member

Registered: 2009-09-29

Posts: 9

Arch and Power Consumption

Hi, I have two questions that I would like to be answered.

Here is some background info:

I've been using Arch almost full time for around 6 months now on my desktop and recently,
I got a laptop and so I decided to install Arch onto it. The install went successfully, but when I started using my laptop,
I was surprised that it ran out of power and shutdown after using it for just under 30 minutes on a full charge.
This made me realize that I now have to take into consideration power consumption - something I didn't have
to care about when using Arch on the desktop.

So I installed powertop and it told me that the power consumption was a whopping 49W.
Naturally, I searched around and used laptop-mode-tools, cpufrequtils, and the other power utilities,
and they almost halved my power consumption to 25W (with wireless, min CPU freq, min backlight).

I was pleased with that result but I still wasn't satisfied, since on Windows 7,
I have wireless turned on, all the fancy aero translucent window effects turned on,
my power consumption is only around 13W (on power-saving mode, 16W on balanced),
while in Arch its 25W, but that's only with a terminal screen.

This brings me to my two questions:

1. Why exactly does Arch consume so much more power than Windows 7 even though I'm only running a terminal in Arch,
while in Windows 7, I'm running a full GUI and other stuff?

2. What else can I do to further reduce my power consumption in Arch? (or what should I focus on tweaking in laptop-mode-tools?)

I apologize if my question was a bit too "newbie" or if post was a bit too long.

I would appreciate if people can help me answer these two questions.

ngoonee

Forum Fellow

From: Between Thailand and Singapore

Registered: 2009-03-17

Posts: 7,356

Re: Arch and Power Consumption

1. Why exactly does Arch consume so much more power than Windows 7 even though I'm only running a terminal in Arch,
while in Windows 7, I'm running a full GUI and other stuff?

2. What else can I do to further reduce my power consumption in Arch? (or what should I focus on tweaking in laptop-mode-tools?)

Both questions are best solved through a search (google search, this is about Linux, not really Arch-specific).

Its a complex scenario, but one of the bigger contributors is the fact that the drivers are different, and the drivers used on windows are typically better (written by the manufacturer, AND meant for a much larger market).

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Allan-Volunteer on the (topic being discussed) mailn lists. You never get the people who matters attention on the forums.
jasonwryan-Installing Arch is a measure of your literacy. Maintaining Arch is a measure of your diligence. Contributing to Arch is a measure of your competence.
Griemak-Bleeding edge, not bleeding flat. Edge denotes falls will occur from time to time. Bring your own parachute.

lucke

Member

From: Poland

Registered: 2004-11-30

Posts: 4,018

Re: Arch and Power Consumption

You could see if adding "pcie_aspm=force" to the kernel line in grub helps. http://www.phoronix.com/scan.php?page=a … _2638_aspm

And "i915.i915_enable_rc6=1" is said to help on sandy bridge hardware.

axel668

Member

Registered: 2009-08-15

Posts: 168

Re: Arch and Power Consumption

Good starting point would be https://wiki.archlinux.org/index.php/Laptop_Mode_Tools (follow the links, too), even if you'd rather use a graphical solution (like e.g. xfce4-power-manager) you will probably need the same kernel modules to actually enable your hardware's power saving options

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"A computer lets you make more mistakes faster than any invention in human history - with the possible exceptions of handguns and tequila."
(Mitch Ratcliffe)