Talk:PowerTOP

uum... how is this related to ibm/lenovo thinkpads? Ra 19:04, 18 September 2007 (UTC)

it is related, as it is a software for linux which helps you to get a longer battery life for your laptop which in this case is a thinkpad ;) --Zhenech 20:07, 18 September 2007 (UTC)

thanks for clarifying (i do use powertop since its released). anyway imho linking to the homepage is ok, but the article does not contain any useful (thinkpad related) information. -- Ra 22:57, 18 September 2007 (UTC)

ibm_acpi wakeups

One of the biggest causes of wakeups on my X31 is ibm-acpi 75% (159.0) <interrupt> : acpi

http://www.lesswatts.org/projects/powertop/known.php#ibm_acpi says: "The ibm_acpi kernel module seems to create a really high number/frequency of ACPI interrupts, which will shorten your battery life a lot. We've not diagnosed this a lot yet, but at this point it's worth trying to unload this kernel module from your kernel."

after follow some of powertop's advice i get down to 8.5-8.4 watts, if i unload ibm-acpi i get down to 8.3 W, with a total of 43 wakeups per second. (this is with an idle gnome desktop on ubuntu hardy with 2.6.24 kernel). does anyone know anything about how to improve ibm-acpi, with out loosing all its useful features.

also forcing HPET seems to increase powerusage by about 0.5 watt. (my statistic are quite low)

followup: getting rid of tp-fancontrol gets rid of 99% of the acpi wake ups.

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Duh, if you have something calling into thinkpad-acpi/ibm-acpi a number of times per second, it is obvious going to cause a lot of wakeups ;-)

tp-fancontrol (which actually NEEDS to at least do one sensor sweep per second, and that's 8 to 12 sensors, and a lot of ACPI interrupts for each one of them), or stupid monitoring applet that doesn't know to not bother the sensors more than once every few seconds will cause wakeups.

--hmh 18:23, 20 June 2008 (CEST)