KDE power management suspends computer to sleep on change of power profile

[Romanescu]

Hello,

I'm kind of surprised from unexcepted behavior of KDE power management. Can someone explain to me, why everytime I change power profile, or plug/unplug power adapter system immediately suspend to sleep mode? I've been trying to restore settings - without success. Even on click "restore settings" button computer goes to sleep. No additional script has been provided to change behavior of power profiles, if I remember correctly, I just changed action when power button is pressed from "shutdown dialog" to "sleep". Changing action back has no effect to described problem.

[SecretCode]

This is a new one for me (and unexpected).

Can you create another, test, user account on your machine and see if the same thing happens when logged into that account?

[tnorris]

I get very similar behaviour on my laptop and I think what causes it goes something like this:
1. Machine is plugged in, and you stop using it for a while (thus the machine state becomes "idle").
2. At some later time you unplug the machine, thus triggering the "On Battery" profile.
3. Because the machine is now "On Battery" and has been "idle" for some time, it immediately triggers the "When laptop lid is closed" choice, which defaults to "sleep".

I'm not 100% positive about this, but it seems to be something like that. This used to drive me CRAZY because I would leave my laptop on all night, plugged in, and then when I would unplug it to move it to my office, it would immediately go into sleep mode. I stopped this by changing the "When laptop lid closed" under the "On Battery" profile to "Turn off screen." If you ask me, when I unplug the laptop, it should restart the idle timer but it doesn't seem to.

[SecretCode]

That's possible. I don't get that behaviour on my laptop but whatever DE or OS I'm using I always set "when laptop lid closed" to do nothing or lock screen, in case I need to carry it around the office. (I'm horrified when I see people carrying half-open laptops - usually with piles of paper or a cup of coffee as well - because it's so easy to drop a laptop like that. Most Windows users seem not even to realise that you can change settings like that.)

[Romanescu]

Thanks for responding After cold start computer and restoring power settings it looks better, at least laptop doesn't fall to sleep on every change of prower profile or plug/unplug power adapter. There are some issues after waking up from sleep mode (computer goes to sleep mode agian), but I can live with that.

Anyway, I've been searching for a while for a GUI based solution for changing laptop's cpu speed management. Can You recommend me something?
I found some suggestions to use power scheme (GUI) script field command: "solid-powermanagement set cpufreq ondemand" or something like that; Can this setting be override on startup/shutdown? Meanig: Fast startup and shutdown, power saving after startup. And more: can be "ondemad" fine tunned (min - max freq)?
Maybe it's a frequently asked question, but I didn't found the answer.

[SteveRiley]

Romanescu, what version of Kubuntu and which kernel are you running? Please let us know the outputs of:

lsb_release -a
uname -a

Recent kernels include support for CPU frequency scaling and default to the "ondemand" governor without requiring additional kernel modules. To verify this behavior on your system, please show the output of:

grep . /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor

[Romanescu]

Thanks, here it is:
Distributor ID: Ubuntu
Description: Ubuntu 11.10
Release: 11.10
Codename: oneiric
Linux ubuntu 3.0.0-12-generic #20-Ubuntu SMP Fri Oct 7 14:56:25 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux

/sys/devices/system/cpu/cpu0/cpufreq/scaling_governorndemand
/sys/devices/system/cpu/cpu1/cpufreq/scaling_governorndemand

[SteveRiley]

So your CPU is, in fact, running with the "ondemand" governor.

You could install the package cpufrequtils, which supplies some commands for altering the governor's behvior. cpufreq-set is the one to examine.

[Romanescu]

OK, thanks. Any idea why Kubuntu goes to sleep while VLC is playing video?

[SteveRiley]

OK, thanks. Any idea why Kubuntu goes to sleep while VLC is playing video?

Hm, not exactly sure. Two questions:

• Have you told VLC to disable power management? (I don't use VLC, but a quick Google search reported this is a possible fix)
• Are you using a screen saver?

[Romanescu]

both disable power management and disable screensaver are chcecked to disable; and there is no screen saver activated.
I was forced to turn off shutting down computer in power management.