System freeze: need help interpreting journalctl output

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1

I am relatively new to Linux and would like to learn how to diagnose crashes/freezes myself. My first question is if anyone knows of good resources to learn how to diagnose these issues?

I am running Manjaro with KDE plasma as desktop environment. My system is a thinkpad t460s.

Here is some basic system info:

CPU: Dual Core Intel Core i5-6200U (-MT MCP-) speed/min/max: 800/400/2800 MHz
Kernel: 5.10.2-2-MANJARO x86_64 Up: 28m
Mem: 2375.8/19315.2 MiB (12.3%)
Storage: 238.47 GiB (26.2% used)

My problem is that my computer freezes every now and again. Keyboard nor touchpad input is responsive (and I cannot switch ttys). I need to shutdown and restart my computer (by holding down the power button) to get the system back.

Looking at the journalctl entries right before the shutdown happened I get the following log repeating quite a lot:

Jan 17 11:43:49 ThinkpadT460s kscreen_backend_launcher[1098]: kscreen.xcb.helper: RRNotify_OutputProperty (ignored)
Jan 17 11:43:49 ThinkpadT460s kscreen_backend_launcher[1098]: kscreen.xcb.helper: Output: 67
Jan 17 11:43:49 ThinkpadT460s kscreen_backend_launcher[1098]: kscreen.xcb.helper: Property: Backlight
Jan 17 11:43:49 ThinkpadT460s kscreen_backend_launcher[1098]: kscreen.xcb.helper: State (newValue, Deleted): 0

Can someone explain if it is normal that the kscreen_backend_launcher outputs this many entries to the log.

The final log entry before reboot:
Jan 17 11:43:53 ThinkpadT460s wpa_supplicant[665]: wlp4s0: CTRL-EVENT-SIGNAL-CHANGE above=1 signal=-64 noise=9999 txrate=270000

Thank you for your time. As mentioned above, I would like to interpret and diagnose issues like this myself. I would appreciate resources where I can learn more about the system.

A

2

Possibly kscreen is in debugging mode, which is not the default according to this post:

https://bugs.kde.org/show_bug.cgi?id=361688

The post also has suggestions as to how to turn off debugging. I’m not a KDE user, so I’m not going to post a specific solution for you. If someone else who is more familiear with KDE can do that, I’m sure it would be appreciated.

Stopping the flood of journal postings may or may not help with your system freezing issue. Good luck!

3

Yeah I found that post as well.

I seriously doubt I changed those settings (unless there is a GUI function somewhere that changes it). There are also others on reddit with the same issue (dated 2020):

I don’t know if it somehow returned.

So it is possible for journal flooding to crash one’s system?

I switched from KDE to XFCE yesterday and thus far I am enjoying the more minimalist way of doing things. So technically I do not have the problem any longer.

Thanks!