I had the same problem with openSUSE 42.3 as I do now with openSUSE Leap 15: occasionally the plasma workspace would freeze and the only solution would be to hit “Alt + F2” and open Konsole and use the following command:
kquitapp5 plasmashell && kstart plasmashell
It occurs utterly random so I realise this makes it difficult to diagnose, but maybe someone has an idea?
Thanks.
Please provide, using the # ] icon above the input window here, the output from the all except the first of the following run in konsole:
sudo zypper in inxi
df /
sudo btrfs filesystem usage /
inxi -GxxxmSC
The first line is not needed if inxi is already installed.
Had to install inxi.
The second line gives:
df /
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda1 20971520 6896272 12395824 36% /
The third line gives:
sudo btrfs filesystem usage /
Overall:
Device size: 20.00GiB
Device allocated: 9.02GiB
Device unallocated: 10.98GiB
Device missing: 0.00B
Used: 6.56GiB
Free (estimated): 11.82GiB (min: 6.33GiB)
Data ratio: 1.00
Metadata ratio: 2.00
Global reserve: 17.75MiB (used: 0.00B)
Data,single: Size:7.01GiB, Used:6.16GiB
/dev/sda1 7.01GiB
Metadata,DUP: Size:1.00GiB, Used:203.58MiB
/dev/sda1 2.00GiB
System,DUP: Size:8.00MiB, Used:16.00KiB
/dev/sda1 16.00MiB
Unallocated:
/dev/sda1 10.98GiB
The fourth line gives (using sudo because the output said that root was required for dmidecode):
sudo inxi -GxxxmSC
System: Host: linux-ynji Kernel: 4.12.14-lp150.12.61-default x86_64 bits: 64 gcc: 7.4.0
Console: tty 0 dm: sddm,sddm Distro: openSUSE Leap 15.0
CPU: Quad core Intel Core i5-2500K (-MCP-) arch: Sandy Bridge rev.7 cache: 6144 KB
flags: (lm nx sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx) bmips: 26340
clock speeds: min/max: 1600/3700 MHz 1: 3292 MHz 2: 3292 MHz 3: 3292 MHz 4: 3292 MHz
Memory: Used/Total: 4221.4/7886.2MB
Array-1 capacity: 32 GB (check) devices: 4 EC: None max module size: 4 GB (est)
Device-1: A0 size: 4 GB (Single-bank) speed: 1333 MT/s type: N/A
bus width: 2244 bits (total: 2304 bits) manufacturer: N/A part: N/A serial: N/A
Device-2: A1 size: No Module Installed type: N/A
Device-3: A2 size: 4 GB (Single-bank) speed: 1333 MT/s type: N/A
bus width: 2244 bits (total: 2304 bits) manufacturer: N/A part: N/A serial: N/A
Device-4: A3 size: No Module Installed type: N/A
Graphics: Card: Intel 2nd Generation Core Processor Family Integrated Graphics Controller
bus-ID: 00:02.0 chip-ID: 8086:0112
Display Server: X.org 1.19.6 drivers: modesetting (unloaded: fbdev,vesa)
tty size: 179x58 Advanced Data: N/A for root out of X
Without sudo produces what I was looking for:
> inxi -Gxxm
Memory: RAM: total: 15.54 GiB used: 3.83 GiB (24.7%)
RAM Report: permissions: Unable to run dmidecode. Root privileges required.
Graphics: Device-1: Intel 4th Generation Core Processor Family Integrated Graphics vendor: Micro-Star MSI driver: i915
v: kernel bus ID: 00:02.0 chip ID: 8086:041e
Display: server: X.Org 1.18.3 driver: modesetting unloaded: fbdev,vesa alternate: intel resolution: 1920x1200~60Hz
OpenGL: renderer: Mesa DRI Intel Haswell v: 4.3 Mesa 17.0.5 compat-v: 3.0 direct render: Yes
See the difference (ignore difference in graphics device, no Sandy Bridge here, and this is from 42.3, so older versions)?
Anyway, RAM availability is not your issue, and neither does / filesystem freespace seem to be ATM, or hardware, or the old DDX (since it’s not in use, xf86-video-intel).
/ filesystem still might be involved. Minimum recommended size for / when using BTRFS is 40GB, because of snapshotting. If you have totally disabled snapshots, then you’re OK with only 20GB, but if not… - did you recently delete all snapshots?
Instead of doing “kquitapp5 plasmashell && kstart plasmashell” right away when it happens, try opening top or htop from Konsole to see if something is hogging CPU.
You could try creating a new user to find out whether something might be corrupt among your personal Plasma settings.
What type, brand and model storage device is your / installed on? If SSD, what does “systemctl status fstrim.timer” report?
15.1 development was finished yesterday. Online upgrades are already possible.
Ah, I thought sudo had timed out.
inxi -GxxxmSC
Resuming in non X mode: glxinfo not found. For package install advice run: inxi --recommends
System: Host: ALEXPC Kernel: 4.12.14-lp150.12.61-default x86_64 bits: 64 gcc: 7.4.0
Desktop: KDE Plasma 5.12.8 (Qt 5.9.4) dm: sddm,sddm Distro: openSUSE Leap 15.0
CPU: Quad core Intel Core i5-2500K (-MCP-) arch: Sandy Bridge rev.7 cache: 6144 KB
flags: (lm nx sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx) bmips: 26339
clock speeds: min/max: 1600/3700 MHz 1: 3292 MHz 2: 3292 MHz 3: 3292 MHz 4: 3292 MHz
Memory: Using dmidecode: root required for dmidecode
Graphics: Card: Intel 2nd Generation Core Processor Family Integrated Graphics Controller
bus-ID: 00:02.0 chip-ID: 8086:0112
Display Server: x11 (X.org 1.19.6 ) drivers: modesetting (unloaded: fbdev,vesa) tty size: 179x58
Still, that doesn’t provide the information like your example.
Yast reports that no snapper configurations exist. Which explains why I didn’t have to keep track of the snapshots.
It’s a fresh openSUSE Leap 15 install. From the DVD image.
I don’t recall something hogging the CPU, but I’ll make sure to check that the next time it happens.
I haven’t checked a new user account yet, because the current one is from early 2018 (I believe it was a new one for 42.3).
It’s a SAMSUNG HD501LJ.
I know 15.1 was about to be published, that’s why I upgraded from 42.3 to 15. 
Must be the annoying antique inxi version (it’s only a script) provided by Leap. Its development version is named pinxi (3.0.34-01). You could upgrade to the much newer one from TW (directly), 3.0.32, or get current from its author, who recommends not using any distro’s package (because they’re virtually always behind), which is what I do:
> inxi -V | head -n1
inxi 3.0.34-00 (2019-04-30)
I keep mine in /usr/local/bin/.
The glxinfo not found message can be stopped too:
> sudo zypper in Mesa-demo-x
Inxi can sometimes self-update using its -U switch if /etc/inxi.conf exists containing “B_ALLOW_UPDATE=true”. Other times trying to update produces error 33.
None of above would affect $SUBJECT.
Has this PC’s internals ever been cleaned? Maybe something occasionally gets overheated? Power supply instability can cause freezing under load. Many power supplies since the middle of the last decade were produced with cheap bargain brand electrolytic capacitors that don’t last like good ones do, like the plague that affected motherboard vendors early in the century, killing Abit and other manufacturers. Bad ones in power supplies are commonly DIY fixed relatively easily, using help from badcaps.net if necessary.
What brand and model is your PC or motherboard? All manufacturers hadn’t all switched all the most important caps from electrolytic to polys by 2011.
New output
inxi -GxxxmSC
System: Host: linux-ynji Kernel: 4.12.14-lp150.12.61-default x86_64 bits: 64 compiler: gcc v: 7.4.0
Desktop: KDE Plasma 5.12.8 tk: Qt 5.9.4 wm: kwin_x11 dm: SDDM Distro: openSUSE Leap 15.0
Memory: RAM: total: 7.70 GiB used: 1.86 GiB (24.2%)
RAM Report: permissions: Unable to run dmidecode. Root privileges required.
CPU: Topology: Quad Core model: Intel Core i5-2500K bits: 64 type: MCP arch: Sandy Bridge rev: 7 L2 cache: 6144 KiB
flags: lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx bogomips: 26340
Speed: 1952 MHz min/max: 1600/3700 MHz Core speeds (MHz): 1: 1952 2: 3189 3: 1642 4: 1768
Graphics: Device-1: Intel 2nd Generation Core Processor Family Integrated Graphics vendor: Gigabyte driver: i915 v: kernel
bus ID: 00:02.0 chip ID: 8086:0112
Display: x11 server: X.Org 1.19.6 driver: modesetting unloaded: fbdev,vesa alternate: intel compositor: kwin_x11
resolution: 1280x1024~60Hz
OpenGL: renderer: Mesa DRI Intel Sandybridge Desktop v: 3.3 Mesa 18.0.2 compat-v: 3.0 direct render: Yes
I try to keep it as clean as I can.
The Simple Monitor Widget reports that the cores are around 30 degrees Celsius.
AFAIK, the power supply works fine.
Don’t know. My hardware knowledge doesn’t go beyond knowing how to install the parts.
PC makers usually put a sticker on the outside of the box somewhere that includes the model number and month of manufacture. Motherboard makers usually stencil their name and a model number in a high contrast color and large type somewhere near the middle of the board.
The problem happened again today, and I think I need to clarify something.
Most often it’s the application menu that stops responding.
The second most often is the system tray that stops responding.
It’s all restricted to the taskbar.
I click on something and it freezes/locks up/stops responding until I do:
kquitapp5 plasmashell && kstart plasmashell
Gigabyte GA-Z68X-UD3H-B3
As @mrmazda wrote in post #4 try with a new user profile to establish whether it’s user or system specific.