Arch Linux

mrunion

Member

From: Jonesborough, TN

Registered: 2007-01-26

Posts: 1,938

Website

"Performance" When on Battery

I have cpufreq set up to run my laptop in "ondemand" all the time.  I have this set up in rc.local and the /etc/cpufreq.conf has the settings I desire for "ondemand" and such.  It's set to go to "ondemand" when on battery power also.  Here's the problem:

When I pull the power cord from my laptop, the screen dims to 50% (as it was configured via power management preferences), but it immediately switches the processors to "performance" mode and maxes them out.  When I plug in the power cord, I go back to "ondemand" and 100% brightness.  I checked the cpufreq.conf file and the settings are correct.  I can issue "cpufreq-set -g ondemand" and the processors will flick to ondemand mode for a few seconds (and NOT decrease their scaling from %100), but will then return almost immediately to "performance".

What else can I check?

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Matt

"It is very difficult to educate the educated."

mrunion

Member

From: Jonesborough, TN

Registered: 2007-01-26

Posts: 1,938

Website

Re: "Performance" When on Battery

OK, answered my own question....

First, I bumped the message level in the cpufreqd.conf to see the messages.  aparently when I'm on battery power it looks to see if I'm watching a movie, and if so increases the performance.  I modified this rule a bit (and had to enable the [acpi] section) and all was well.

Thanks guys!

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Matt

"It is very difficult to educate the educated."