my pc desktop: CPU (Processor):Intel Core i5-7400 4x3.00GHz 7th Kaby Lake, Mainboard:B250M MSI Pro-VDH (7A70-003R), Video Card (VGA Card) onBoard Graphic, System Memory (RAM):8GB Kingston DDR4-2400, SSD:240GB Western Digital WD Green M.2
running leap 42.3 with KDE when I boot it is fast and responsive, after one day staying on and with no operations by a user it becames slow and laggy, mouse is slow, selection is slow ecc, only reboot solve, and after reboot it start again to be responsive. I think 8Gb is ok, could it be the SSD managing by leap42.3??
I can I solve this problem??
many thanks, 
ciao
and have you looked at cpu usage and memory allocation?
something like top??
here is top: in a slow situation
Tasks: 218 total, 2 running, 216 sleeping, 0 stopped, 0 zombie
%Cpu(s): 26.0 us, 28.9 sy, 0.0 ni, 43.0 id, 0.1 wa, 0.0 hi, 2.0 si, 0.0 st
KiB Mem: 8065988 total, 7928520 used, 137468 free, 78788 buffers
KiB Swap: 2104316 total, 293436 used, 1810880 free. 7084752 cached Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1953 procuste 20 0 4635296 425188 46028 S 149.7 5.271 1853:33 plasmashell
1613 root 20 0 313100 106056 16816 R 77.33 1.315 866:57.76 X
1252 nscd 20 0 1077040 2724 2284 S 1.667 0.034 3:48.56 nscd
2303 procuste 20 0 1623712 64184 28500 S 0.667 0.796 19:56.19 ktorrent
3 root 20 0 0 0 0 S 0.333 0.000 0:04.33 ksoftirqd/0
1937 procuste 20 0 3272192 59916 36116 S 0.333 0.743 7:13.82 kwin_x11
2053 procuste 20 0 9856 1948 1672 S 0.333 0.024 2:11.60 ksysguardd
1 root 20 0 185300 5440 3936 S 0.000 0.067 0:06.66 systemd
not that familiar with top but at the instant plasmashell looks to be high consumer. check any rouge widgets installed you have installed. [ps there used to be a bug in plasmashell whereby any animation in task bar would slow system - e.g. copy file animation] but this has been fixed ages ago though leap i suppose is on old version.
Do you use modesetting driver for graphics? I have slowdowns after some time using it on my Broadwell. Slowdowns dissapear after update to latest Xorg/Mesa.
I’ve read some bug reports about plasmashell exhibiting this behavior in some other scenarios too: when a background slideshow changes wallpaper, and with two monitors (I think when you switch monitors or something like that).
manythanks guys, I will try first to remove slideshow (and I have only one monitor )
If the slideshow wallpaper is the culprit, which is quite likely, you can apply a patch to “/usr/share/plasma/wallpapers/org.kde.slideshow/contents/ui/main.qml” as outlined in this bug report:
it seems that the slideshow isn’t the culprit, I set wallpaper as a single color and rebooted but after 1day the slow mouse and lag exist again
I’ll try to apply the patch anyway… 
If changing to a static image made no difference then I doubt applying that patch will help, although you’ve nothing to lose by trying.
There’s a generic bug report for high CPU utilisation: 378010 – Generic High CPU Usage Rendering … all rather vague, but there may be something of relevance in amongst it.
As a temporary “fix” you could periodically restart plasma shell, that will probably restore things for a while without the need for a complete re-boot.
Use Alt-F2 and enter the command:
kquitapp5 plasmashell && kstart plasmashell
First create a new user, login as that user ans see if the issue exists for that user. If not, the issue is in your homedir
I had similar issues on 42.3 with latest KDE from https://en.opensuse.org/SDB:KDE_repositories#Get_the_latest_KDE_Framework_and_Plasma_5_releases
I changed Compositor settings to xRender and it does not become slaggy to soon. Unfortunately it is a work pc so I reboot it every night (logging off also works) and do not have time to troubleshoot.
It is annoying either way…
ps I have two monitors
manythanks, as “temporary fix” it works lol!
Manythanks, It seems you are right Knurpht !!!
with a new user after e couple of days the lag and slow disappear!!
…what do you suggest to reset my culprit homedir as if I was a new user without losing all other settings and passwords??
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