Bug 348082 - monitor is randomly powered back on
Summary: monitor is randomly powered back on
Alias: None
Product: Powerdevil
Classification: Plasma
Component: general (show other bugs)
Version: 5.20.3
Platform: Kubuntu Linux
: NOR normal
Target Milestone: ---
Assignee: Plasma Bugs List
Depends on:
Reported: 2015-05-21 18:47 UTC by fr.frasc
Modified: 2022-09-15 23:07 UTC (History)
14 users (show)

See Also:
Latest Commit:
Version Fixed In:


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Description fr.frasc 2015-05-21 18:47:40 UTC
PM has been configured to turn monitor off after 30 minutes.
Screen locking has been configured to lock screen after 15 minutes and require a password after 30 seconds.

The screen gets locked as expected, and the monitor is powered off in time.

However, after a seemingly random amount of time, without any event that I can account for, the monitor wakes up, showing the lock screen.

Tasks might be running in the background (but not always): compilations and/or virtual machines and/or lengthy wget/curl/rsync

The hardware configuration, is dual monitor. Main monitor, landscape. Second monitor, portrait, configured to be on the left of main monitor.
OS is Kubuntu 15.04

Reproducible: Sometimes

Steps to Reproduce:
1. Configure Display to lock screens after 15 minutes and require password after 30seconds.
2. Configure PM to turn monitor off after 30 minutes.
3. Leave the computer totally unattended.

Actual Results:  
Screen will get locked after 15minutes.
Monitor turns off after 30minutes
Monitor randomly turns back on, revealing the lock screen.
Monitor turns off again after some time. Probably 30minutes, but unverified.
The turn off/wake up cycle will loop up to 3 times in one night.

Expected Results:  
Screen will get locked after 15minutes.
Monitor turns off after 30minutes
Monitor stays off until an HID event wakes it up.
Comment 1 Martin Klapetek 2015-05-22 09:05:49 UTC
I've seen this too. Often I leave my desktop pc on in the evenings with the timeout being 10 minutes and even if there's absolutely no activity around the pc, sometimes the screen just comes on on its own, then powers off again after 10 minutes and so on.

But I'm also yet to see any pattern.
Comment 2 fr.frasc 2015-05-22 23:20:13 UTC
Is there a way to trace which event is triggering that wake up ?
Would a regular build allow for such a trace or is there need for a debug build ?

As reproducing that bug is very lengthy, I volunteer to let it run, gather traces and send them out.

Please let me know.
Comment 3 Lindsay Roberts 2015-05-31 13:21:14 UTC
Do you have it configured to suspend session? In my setup, suspend (sleep) was causing the issue -- there are many ways ACPI wakeup can be triggered. There is a simple way to test: manually suspend ("Suspend To RAM" in krunner). If your machine blanks and wakes back up in a few seconds, this is the issue.

Unfortunately if so, you are looking at an ACPI issue, which is likely a hardware/kernel layer quirk. There is lots of talk out there about it, but there doesn't seem to be any simple way of debugging what device woke up your machine. The best way seems to be disabling wakeup devices from /proc/acpi/wakeup one by one until your machine sleeps.
Comment 4 Martin Klapetek 2015-05-31 13:42:25 UTC
In my case, my desktop machine is configured to never sleep/suspend. However, the cause may indeed be the same/related.
Comment 5 fr.frasc 2015-05-31 22:32:15 UTC
Good news so far, is that since kubuntu has deployed updates to 5.3.1, I haven't seen the problem. I will watch for it and report accordingly.

Thank you guys for looking into it!
Comment 6 fr.frasc 2015-06-01 21:46:18 UTC
Actually the problem is still present :-( Just it hadn't happened in the first two days after update to 5.3.1

No, my machine is not configured to suspend session. I did however verify that the spurious wakeup issue is not present in my case.

I wish there was an easy way to trace the wakeup events so I could report the data.

The only workaround I can think of is manually hitting the monitor power switch. This has the undesired side effect of powering off the monitor USB Hub, and the USB devices attached to it.
So, in turn I need to find a workaround to Phonon losing the audio devices and not recovering them when power is back up. But that's another bug to be opened for Phonon.

Thank you all!
Comment 7 Mark Haase 2015-08-30 03:54:58 UTC
I was having a similar problem after upgrading to Kubuntu 15.04. I finally solved it today by removing ~/.kde/share/config/powermanagementprofilesrc, logging out, and logging back in.

This drove me nuts -- I spent several hours trying to diagnose it. Then I realized if I create a new user and log into that user, then power management works correctly. That set me on to figuring out which rc file to remove.

Hope this helps somebody!
Comment 8 Mark Haase 2015-08-30 15:39:12 UTC
Nevermind, my problem persists :(
Comment 9 Greg Lepore 2015-10-25 21:01:17 UTC
I am having a problem identical to this with Kubuntu 15.10. Any suggestions for debugging?
Comment 10 Kai Uwe Broulik 2015-11-23 16:02:58 UTC
Could you perhaps try https://git.reviewboard.kde.org/r/126145/ ?
Comment 11 fr.frasc 2015-11-26 21:39:27 UTC
I've been noticing that the problem might go away if I unplug the USB trackball.
I'm playing with xinput to try find some settings that might address it permanently.
Comment 12 Justin Zobel 2020-11-12 22:01:47 UTC
Mice are often the culprit. Mine used to wake up all the time long ago (previous mouse).

They're so sensitive.. Try unplugging your mouse and see if it occurs after that.
Comment 13 fr.frasc 2020-11-13 22:05:18 UTC
I'm now using Gentoo, with:

The problem seems to be really tied to the mouse itself.
It's actually a trackball:
Kensington Slimblade Trackball

I have to disconnect the trackball from its USB bus to not get randomly woken-up.

It doesn't appear to be a powerdevil bug.

Maybe implementing or documenting a finer granularity on what events can wake-up the system would allow to ignore mouse events. But that's just a wish-list item.

Comment 14 Justin Zobel 2020-11-13 22:56:15 UTC
Moving to wishlist for power savings kcm.
Comment 15 Patrick Silva 2021-05-09 12:43:33 UTC
My Arch Linux is affected. When this behavior occurs on Wayland, Frequently my
hdmi monitor does not enter in power saving mode again until Plasma session
is restarted, what can damage the monitor. That's why I always turn my monitor
off manually when I need to leave my computer for a long time.

Operating System: Arch Linux
KDE Plasma Version: 5.21.5
KDE Frameworks Version: 5.82.0
Qt Version: 5.15.2
Comment 16 Méven Car 2021-05-10 07:20:20 UTC
(In reply to Patrick Silva from comment #15)
> My Arch Linux is affected. When this behavior occurs on Wayland, Frequently
> my
> hdmi monitor does not enter in power saving mode again until Plasma session
> is restarted, what can damage the monitor. That's why I always turn my
> monitor
> off manually when I need to leave my computer for a long time.
> Operating System: Arch Linux
> KDE Plasma Version: 5.21.5
> KDE Frameworks Version: 5.82.0
> Qt Version: 5.15.2

Do you have a trackball mouse as well ?
Is it mouse related in your case too ?
Comment 17 Patrick Silva 2021-05-15 09:21:34 UTC
(In reply to Méven Car from comment #16) 
> Do you have a trackball mouse as well ?
> Is it mouse related in your case too ?

No, I use a basic usb mouse.
The problem did not happen since my previous commment.
I will comment here if it happens again.
Comment 18 Patrick Silva 2021-06-14 23:23:17 UTC
This problem happened 5 times on my Arch Linux
since my previous comment here, once on X11 and 4 times
on Wayland (3 today after logout from X11 session).
On X11, my monitor spontaneously enters in power saving mode again when the timeout configured in Energy Saving KCM is reached.
However, on Wayland the monitor does not enter
in power saving mode again until some keyboard key is pressed
(I pressed CTRL today) or mouse is moved.
I do not know if the bug is related to usb mouse yet.

This bug will potentially damage many monitors if it is not fixed
before Wayland session of Plasma becoming popular.

Operating System: Arch Linux
KDE Plasma Version: 5.22.0
KDE Frameworks Version: 5.83.0
Qt Version: 5.15.2
Graphics Platform: Wayland
Comment 19 Patrick Silva 2021-07-25 13:01:44 UTC
This bug no longer occurs on my Arch Linux since ddcutil support was disabled
29 days ago.

Comment 20 Chris 2021-08-02 23:04:49 UTC
I've been experiencing this bug for a few years.
My debian kde version is now sid/experimental/wayland. (Plasma 5.21)
Powerdevil is installed, but nothing ddcutil: debian doesn't have the dependency.
I think the bug description should be reverted to what it was until a week ago.
Comment 21 Chris 2021-08-06 19:44:01 UTC
No `ddcutil` on debian. Still definitely subject to the bug. Hence reverting the bug short description to what it was initially.
Comment 22 Chris 2021-08-08 19:26:20 UTC
It's probably not good for the monitor, it turning on and off, again and again, without ever ending. Even if it's at a slow pace, the full cycle taking maybe 30 min.
This time, it was after two reboot, w/o login, then login, and not touch anything, not launching any app. After 10 min, which is consistent with my timer setting, the screen turns off. But then, like 20 min later it turns back on, all by itself. Then back off. Etc.
Sometimes it never turns off.
Sometimes the screen locker doesn't even kick in, which can be considered a security issue.
Sometimes, it turns off, then turns back on, then never turns back off again.
Things might get better when I hit Plasma 5.22.
Also when my sddm will use wayland, therefore in match with the session.
For now turn off screen, and even the locker, are mostly random. I can't rely on them working, at all.
Related but not duplicate:
Remotely related:
Comment 23 Chris 2021-08-09 17:45:24 UTC
Power computer on, login with sddm (wayland session), then no interaction.
After 10 min, "Turn Off Screen" kicks in, as it should.
At that moment, the computer remains visually as cold and dumb as a stone for something like 2 hours.
For those advocating, always, it's the mouse, it's the mouse, a lot of activity took place near the computer during that time.
Anyway, at the chime of 2 hours, the screen spontaneously turned on, and remained so indefinitely (at least 1 hour).
Comment 24 Patrick Silva 2021-10-01 15:36:08 UTC
Oh no, my hdmi monitor left power saving mode spontaneously again
on Wayland session of Plasma 5.23 beta running on Arch Linux.
And power saving mode was not re-activated after the timeout
until I moved the cursor.

Operating System: Arch Linux
KDE Plasma Version: 5.22.90
KDE Frameworks Version: 5.86.0
Qt Version: 5.15.2
Graphics Platform: Wayland
Comment 25 Patrick Silva 2021-10-20 00:54:19 UTC
Well, a few days ago I needed to use Windows 7 installed on my machine together Arch to fix some errors in a ntfs partition with chkdsk command and...
My hdmi monitor left power saving mode sponteneously there too.
Then I remembered that the ancient CRT monitor (VGA connection) that I used before my current monitor also had the same problem. Therefore, at least in my case KDE software is not the culprit. There is something wrong with my hardware. :(
Comment 26 Chris 2021-10-26 16:21:11 UTC
My configuration is a tp x230, i5-3210m, dp external monitor Dell p2715q.
System is debian sid, 5.14.0-3-amd64, P 5.23.0 F 5.86.0, wayland, save for sddm 0.19, which is still using x11.
First step, after 10 min, both screens turn cold as stone, as they are expected to.
Then, something like 10 min later, they both turn back on. Starting with the laptop monitor, likely because it's much faster at turning on.
That with no interaction whatsoever, and don't bring the fancy mouse here, it can control its temper during an earthquake when it's in the mood to.
This scenario makes me think it's more likely the wake-up call comes from the pc than from the screen?
50% of the time, depending on its mood, it doesn't do that at all, and keeps the monitor off indefinitely when there is no user interaction.
I've searched and asked, and I didn't find the tiniest clue on how to debug that, have some insight on what's going on. I only have the view from the outside, and that is of erratic behavior.
Comment 27 Yuking 2021-10-29 17:30:02 UTC
The problem still exists even no mouse and keyboard connected.

KDE Plasma Version: 5.23.80
KDE Frameworks Version: 5.88.0
Qt Version: 5.15.2
Kernel Version: 5.15.0-rc6 (64-bit)
Graphics Platform: X11
Processors: 24 × AMD Ryzen 9 3900X 12-Core Processor
Memory: 125.8 GiB of RAM
Graphics Processor: AMD Radeon VII
Comment 28 Chris 2022-05-29 20:16:07 UTC
The issue no longer occurs for me. Hardware configuration hasn't changed, mouse, keyboard, monitor, etc. Latest debian-sid, wayland as pure as possible.
Comment 29 Patrick Silva 2022-05-29 20:22:26 UTC
This bug persists on my Arch Linux running Plasma 5.25 beta.
Comment 30 Patrick Silva 2022-09-15 23:07:33 UTC
Plasma 5.26 beta is affected.

Operating System: Arch Linux
KDE Plasma Version: 5.25.90
KDE Frameworks Version: 5.98.0
Qt Version: 5.15.6
Graphics Platform: Wayland