cpupower vs cpufrequtil

Hi folks,

on my T430s I was trying to get better battery life. Finally I was successful, thanks to Arch forums https://bbs.archlinux.org/viewtopic.php?id=135820 . (the right solution for me was: i915 kernel cmdline options + laptop-mode-tools + cpupower).

With cpufrequtils package installed I cannot get better battery life, but once I’ve replace it by cpupower (emerge -C cpufrequtils && emerge cpupower) the battery life was doubled!

So far I understand that cpufrequtils package is intended to use with older CPUs (older than core2duo), and cpupower is to be used with newer CPUs. This appear to be true in my case.

The question is, why default installation of Calculate linux contains cpufrequtils instead of cpupower ?

Maybe installer could detect the cpu during the installation and decide which one to install. Also, adding the Laptop option to the installer would be great.

Please correct me if I made wrong presumption in some point.

Hi Marek,
Thanks for the suggestion. In the near future we’ll see.

Is there anything you did after emerging cpupower? Did you need to delete or adjust any config files?


after emerging you need to add the service to default runlevel

 # rc-update add cpupower default
 # rc-update add laptop_mode default

and/or start the services by hand without reset

 # /etc/init.d/cpupower
 # /etc/init.d/laptop_mode

I don’t remember any special changes in config files. But you maybe want to play with /etc/laptop-mode/conf.d/ files.

Here are my cmdline options for grub2 in case you are interested (/etc/default/grub)

GRUB_CMDLINE_LINUX="... i915.i915_enable_rc6=1 i915.i915_enable_fbc=1 
i915.lvds_downclock=1 i915.semaphores=1 acpi_backlight=vendor"

After refreshing your grub configuration you can try to reboot to see the changes

 # grub-mkconfig -o /boot/grub/grub.cfg

NOTE that using the “i915.lvds_downclock=1” option I’ve experienced some video performance problems on the T440s. Also note that T440s needs different option “acpi_backlight=’!Windows2012’” option to fix the backlight control, compare to the T430.

I also need to update settings in /etc/laptop-mode/conf.d/cpufreq.conf


This would allow other daemons to control cpu frequency. More info here: http://wiki.gentoo.org/wiki/Power_management/HOWTO#About_laptop_mode