Not sure if this was ever discussed before. I recently rebuilt my Ubuntu laptop and when doing this particular config I thought this is one of those things that no one ever told me about and I just picked it up along the way. So I thought I would share for anyone who is running Linux on their laptop.
To extend the battery life on my T61 2.5GHz Core 2 Duo I do the following. sudo modprobe acpi-cpufreq sudo modprobe cpufreq_ondemand sudo apt-get install sysfsutils sudo echo "devices/system/cpu/cpu0/cpufreq/scaling_governor=ondemand" >> /etc/sysfs.conf I thought I might have to also enter sudo echo "devices/system/cpu/cpu1/cpufreq/scaling_governor=ondemand" >> /etc/sysfs.conf but that does not appear to be the case. Both cores seems to be governed with just the first line. In any case the system runs both processors at 800MHz until more is needed and it steps it up to what as needed. 1.2, 1.6... all they way to 2.5GHz. It drops back down with no issues. Sometimes only going to the full speed briefly when launching an app like FF then it just drops back down to 800. Battery life (9cell) has gone from 3.5 to almost 5 hours.I've noticed while playing DVDs it stays at 800. Your mileage may vary, enjoy. Chris -- [email protected] http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-newbie
