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dienadel

Member

From: Basque Country (Spain)

Registered: 2005-12-23

Posts: 179

CPU freq control: cpufreq, laptop-mode, both?

Hello!

I control the CPU freq of my laptop with the cpufreq daemon. All is perfect. But now, i want to control more things with laptopmode-tools. This pkg seems to be capable of control the CPU freq as specified in /etc/laptop-mode/conf.d/cpufreq.conf.

If i choose laptop-mode to control the CPU freq, should i stop cpufreq daemon doing that work? or, laptop-mode simply calls cpufreq daemon? or laptop-mode simply needs the modules provided by cpufreq? or cpufreq isn't needed at all? :-(

Thanks!!

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Dienadel

kclive18

Member

From: Columbus, Ohio, USA

Registered: 2008-05-08

Posts: 219

Re: CPU freq control: cpufreq, laptop-mode, both?

http://www.linuxjournal.com/article/7539

According to that article, written by the creator of laptopmode-tools himself, laptopmode only controls hard drive activity and memory management.  It cannot control your CPU's frequency.

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fwojciec

Member

Registered: 2007-05-20

Posts: 1,411

Re: CPU freq control: cpufreq, laptop-mode, both?

http://www.linuxjournal.com/article/7539

According to that article, written by the creator of laptopmode-tools himself, laptopmode only controls hard drive activity and memory management.  It cannot control your CPU's frequency.

The article is from 2004 -- perhaps things have changed since then.  Laptopmode can control the cpu frequencies as well, and it doesn't need the cpufreq daemon to do it.

dienadel

Member

From: Basque Country (Spain)

Registered: 2005-12-23

Posts: 179

Re: CPU freq control: cpufreq, laptop-mode, both?

http://www.linuxjournal.com/article/7539
According to that article, written by the creator of laptopmode-tools himself, laptopmode only controls hard drive activity and memory management.  It cannot control your CPU's frequency.

Here is the file that seems control the CPU freq:

#
# Configuration file for Laptop Mode Tools module cpufreq.
#
# For more information, consult the laptop-mode.conf(8) manual page.
#

###############################################################################
# CPU frequency scaling and throttling
# ------------------------------------
#
# Laptop mode tools can automatically adjust your kernel CPU frequency
# settings. This includes upper and lower limits and scaling governors.
# There is also support for CPU throttling, on systems that don't support
# frequency scaling.
#
# This feature only works on 2.6 kernels.
#
#
# IMPORTANT: In versions 1.36 and earlier, these settings were included in the
# main laptop-mode.conf configuration file. If they are still present, they
# overrule the settings in this file. To fix this, simply delete the settings
# from the main config file.
#
###############################################################################


#
# Should laptop mode tools control the CPU frequency settings?
#
CONTROL_CPU_FREQUENCY=0


#
# Legal values are "slowest" for the slowest speed that your
# CPU is able to operate at, "fastest" for the fastest speed,
# "medium" for some value in the middle, or any value listed in
# /sys/devices/system/cpu/cpu*/cpufreq/scaling_available_frequencies.
# The "governor" can be any governor installed on your system, this usually
# includes "ondemand", "conservative", and "performance". The
# "IGNORE_NICE_LOAD" setting specifies that background programs that have
# a low priority ("nice level") should not cause the CPU frequency to
# be increased. (You generally want this to be enabled in battery mode.)
#
BATT_CPU_MAXFREQ=fastest
BATT_CPU_MINFREQ=slowest
BATT_CPU_GOVERNOR=ondemand
BATT_CPU_IGNORE_NICE_LOAD=1
LM_AC_CPU_MAXFREQ=fastest
LM_AC_CPU_MINFREQ=slowest
LM_AC_CPU_GOVERNOR=ondemand
LM_AC_CPU_IGNORE_NICE_LOAD=1
NOLM_AC_CPU_MAXFREQ=fastest
NOLM_AC_CPU_MINFREQ=slowest
NOLM_AC_CPU_GOVERNOR=ondemand
NOLM_AC_CPU_IGNORE_NICE_LOAD=0


#
# Should laptop mode tools control the CPU throttling? This is only useful
# on processors that don't have frequency scaling.
# (Only works when you have /proc/acpi/processor/CPU*/throttling.)
#
CONTROL_CPU_THROTTLING=0


#
# Legal values are "maximum" for the maximum (slowest) throttling level,
# "minimum" for minimum (fastest) throttling level, "medium" for a value
# somewhere in the middle (this is usually 50% for P4s), or any value listed
# in /proc/acpi/processor/CPU*/throttling. Be careful when using "maximum":
# this may be _very_ slow (in fact, with P4s it slows down the processor
# by a factor 8).
#
BATT_CPU_THROTTLING=medium
LM_AC_CPU_THROTTLING=medium
NOLM_AC_CPU_THROTTLING=minimum

For a laptop seems better than cpufreq, as i can define different  governors, whether the battery is plugged or not.

and it doesn't need the cpufreq daemon to do it.

Nice, i'll make a few tests in the next weeks. Nowadays i'm quite busy. I'll post here the results, so, if anyone with the same doubt, will have the answer.

Thanks!

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Dienadel