I saw this only after the transition from Qt 5.7 --> Qt 5.9 in Tumbleweed too. It always appeared after switching activities, but removal of the weather plasmoid from the panel resolved it for me (up to now, at least).
Did you also have this third-party plasmoid installed?

robsn81 wrote:I saw this only after the transition from Qt 5.7 --> Qt 5.9 in Tumbleweed too. It always appeared after switching activities, but removal of the weather plasmoid from the panel resolved it for me (up to now, at least).
Did you also have this third-party plasmoid installed?

I have plasma 5.8.7 and no issues. I also have 7 widgets on the desktop of my second monitor including the weather widget. I had problems in Neon, but with Kubuntu 16.x LTS no issues unless I launch Boinc manager, then resources start to get gobbled up. Once I close the Boinc manager app, it returns to normal. Weird...

compatico wrote:

robsn81 wrote:I saw this only after the transition from Qt 5.7 --> Qt 5.9 in Tumbleweed too. It always appeared after switching activities, but removal of the weather plasmoid from the panel resolved it for me (up to now, at least).
Did you also have this third-party plasmoid installed?

I have plasma 5.8.7 and no issues. I also have 7 widgets on the desktop of my second monitor including the weather widget. I had problems in Neon, but with Kubuntu 16.x LTS no issues unless I launch Boinc manager, then resources start to get gobbled up. Once I close the Boinc manager app, it returns to normal. Weird...

Oh this seems interesting .. Do you have the current plasma 5.8.7 with which QT version running?. I have the LTS repositories ( 5.8.7 and QT 5.6 I think) and is rock solid version.

juan-lutz wrote:

compatico wrote:

robsn81 wrote:Oh this seems interesting .. Do you have the current plasma 5.8.7 with which QT version running?. I have the LTS repositories ( 5.8.7 and QT 5.6 I think) and is rock solid version.

Well it's back...I ran about 20 days before usage creeped up to 30%+...currently Plasma 5.8.7 Qt 5.6.1 - the bug isn't fixed...

I'm having a similar issue and have spent weeks trying to solve the high CPU with plasmashell problem!
CPU usage starts at 2-3% and gradually climbs until the system is sluggish, and the CPU usage is typically from 20% to 150%.
The only thing that I've found that helps is restarting plasmashell.

I've updated and cleaned everything I can think of, and tried all the various "fixes" that were offered by others, but nothing seems to solve the issue.
I've read dozens of reports of this same issue occurring with plasmashell (over many years) and wonder if there is not some sort of definitive way to diagnose and potentially solve this very common issue?
I'm a big fan of KDE and would hate to have to abandon it because of this seemingly intractable problem

Anyone with ideas on how to solve this issue please let me know?

Same here with plasmashell 5.9.5.

gtozzi wrote:

I'm having a similar issue and have spent weeks trying to solve the high CPU with plasmashell problem!
CPU usage starts at 2-3% and gradually climbs until the system is sluggish, and the CPU usage is typically from 20% to 150%.
The only thing that I've found that helps is restarting plasmashell.

Same here with plasmashell 5.9.5.

Oddly enough I've found that it's not any of my desktop widgets or regular apps - for me it's Boinc Manager that causes Plasmashell to go nuts. I don't need the manager running all the time so I open it as needed. Once closed, usage drops back down. Also file copy / paste causes very high usage, but again only while it's actively moving data bits. Once the copy process is complete, usage drops back down too.

For reference I have the following widgets running 24/7:

CPU Load Monitor
Network Monitor
Hard Disk I/O Monitor (3 drives)
Weather
Thermal Monitor (cpu and drives)
Uptime
System Clock

I also have Gpredict and VLC running 24/7 plus Chrome with a dozen tabs, Thunderbird, and various apps as needed. As long as I open Boinc only as needed, no issues. I really only reboot when Kubuntu updates the kernel or other system files forcing a reboot.

Is there a command to show plasmashell CPU usage by "subprocess"?

gtozzi wrote:Is there a command to show plasmashell CPU usage by "subprocess"?

The closest I know of is the terminal command line TOP using capital H to show all threads. I haven't been able to narrow down why certain apps cause Xorg and Plasmashell to go nuts.

Hi,
don't if that might help somebody else but never knows. For me the origin of the problem was the slideshow for the desktop background. Changing it to a static image fixed the issue for me.
Cheers,

plasma 5.10.5
frameworks 5.38
apps 17.08
qt 5.9.2

deweerd wrote:Hi,
don't if that might help somebody else but never knows. For me the origin of the problem was the slideshow for the desktop background. Changing it to a static image fixed the issue for me.

Unfortunately this is a known bug, reported ~6 months ago.

After a clean install of Kubuntu 17.10 on my Lenovo laptop, Plasma is 'jitterish'.
It seems like every 10 seconds a window id opened and closed, the (default laptop) screen is rebuild, text lines jump and jump back.

The system is sluggish and unresponsive, it often takes a few seconds for the KDE menu to appear or to process other actions via the GUI.
Even with 2 windows active (Firefox + bash shell running top), the CPU load is remarkably high, it never goes below 19% (with a fast i3 cpu):

Tasks: 184 total, 1 running, 183 sleeping, 0 stopped, 0 zombie
%Cpu(s): 16,3 us, 5,9 sy, 0,0 ni, 77,6 id, 0,0 wa, 0,0 hi, 0,2 si, 0,0 st
KiB Mem : 3897600 total, 595140 free, 1269560 used, 2032900 buff/cache
KiB Swap: 1580316 total, 1580316 free, 0 used. 2220348 avail Mem

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1307 henk-jan 20 0 0,255t 230156 142504 S 32,9 5,9 11:02.70 plasmashell
1295 henk-jan 20 0 3466576 174128 99484 S 26,3 4,5 10:23.98 kwin_x11
942 root 20 0 377548 90104 59236 S 16,1 2,3 4:48.85 Xorg

I have the exact same issues with what 1user2 above reports, on my Dell Latitude. The desktop is not usable anymore for the last month that I did the mistake of upgrading from 16.04 LTS which was fine.

It's really unfortunate that this affects the core functionality of the desktop for so many people and hasn't been resolved yet. We are not talking about something small related to a small 'feature' of the desktop, I mean the whole desktop functionality is broken right after installation. I thought that this completely broken situation on a Linux desktop was a distant memory from the past. Please whoever from the development team reads these posts make it a priority as it is very serious and I repeat the desktop is completely unusable, windows hang due to the high CPU usage on a 2 core machine and last but not least battery drains 5 times faster than usual.

Of-course I understand it might be pretty complicated and users are certainly patient enough all these months waiting for a fix. Downgrading to 16.04 with a full reinstall is not really a reasonable alternative for many people.

Same problem with plasma 5.10.2 in Debian.
Solved by disabling the tiny RSIBreak widget in the taskbar. It took several minutes for the CPU usage to drop. There was a lot of hard disk activity, with md5sum and udisksd high usage in top, that seemed related to plasmashell. Now both have dropped : md5sum to 0, and udisksd still appearing regularly at 5% with plasmashell.
My installation was recent.
I use two monitors (VGA + DVI). I used arandr at some point to set the correct positions for my monitors (left and right positions like on my desk), which kde could not do in the system settings. It created a very annoying problem : I had set the taskbar to disappear automatically, but it was impossible to access it for maybe half an hour if I used a specific software : gnome disk utility. Maybe this is related.

I had the same problem with kde and archlinux, after i changed the qml file, now is ok.
The problem is very old, i had it with kde neon with manajro kde .
The problem was copying file from hdd to hdd or usb drive all have the same result. System lags unusable or it freeze complet.
Now i am happy with the desktop, except other problem with kde and steam after playing in steam kde says some config files from kde are not writeable.

eliask wrote:Of-course I understand it might be pretty complicated and users are certainly patient enough all these months waiting for a fix. Downgrading to 16.04 with a full reinstall is not really a reasonable alternative for many people.

It's an odd bug because it doesn't appear on my 16.04.4 LTS setup with backports enabled. Currently on v5.8.8 with QT 5.6.1. If I bring up the Boinc manager usage climbs but drops again once Boinc is closed. I won't be upgrading to v17.x or v18.x until the mouse issue is fixed either - I have a multi-monitor setup and the horribly slow mouse makes the desktop unusable, even with tools to increase mouse speed, it's still too slow.