Bug 158349

Summary:	High CPU usage by X and plasma processes when moving mouse cursor near the plasmoid edge
Product:	[Unmaintained] plasma4	Reporter:	Andrey <andrey>
Component:	general	Assignee:	Plasma Bugs List <plasma-bugs>
Status:	RESOLVED FIXED
Severity:	normal	CC:	grundleborg, rdieter
Priority:	NOR
Version:	unspecified
Target Milestone:	---
Platform:	Compiled Sources
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description Andrey 2008-02-24 19:39:48 UTC

Version:            (using Devel)
Installed from:    Compiled sources
Compiler:          gcc-4.2.3 
OS:                Linux

Currently I have three plasmoids on the desktop (except panel and plasmoids on the panel): Dictionary, Notes, Picture frame. They are locked using RMB - Lock Widgets. Desktop effects are completely disabled.

1) When mouse cursor crosses the plasmoid border, CPU usage for X proccess grows up to 50-60% (which is too high, I think) and plasma proccess consumes 5-10% of CPU. 
2) If I just move the mouse around the wallpaper, X uses ~10% of CPU and plasma less than 1%. 
3) If I move mouse cursor above the content of one of the plasmoids (not crossing the plasmoid's border), CPU usage is 5-10% for each process.

2 and 3 cases are ok, but the first case seems suspicious to me. When widgets are locked, if I point mouse cursor at them, nothing happens. I mean, there's no slowly-appearing transparent border, so X doesn't do any real work and CPU usage by X proccess must not be high. 

Here's a screenshot: http://img178.imageshack.us/img178/9738/46773394ml4.png - I was continuously moving mouse cursor from Notes plasmoid to the wallpaper.

Sorry for my bad language knowledge and explanation. I will provide any additional information if needed.

Comment 1 George 2008-03-15 15:57:00 UTC

can you reproduce it in kde 4.0.2 ?
and just to be on the safe side, move your $HOME/.kde and $HOME/.kde4 directories to some other place and reboot to force kde to make new config files 
I tried to reproduce it on kde 4.0.2 on my machine, but perhaps you have other hardware and/or enviroment, like proprietary ati/nvidia video display drivers installed.

Comment 2 Dimitris 2008-05-30 13:14:11 UTC

I would like to verify the above situation.

I have only one plasmoid on desktop, it's the folder view. 
When i move the cursor to the boundaried of the plasmoid i have around 30% cpu usage from X and 20% from plasma. This happens as well wehn i move the mouse cursor over the "files" showed bye the plasmoid.

I also wanted to add that when i move fast a window around the screen, i have 100% cpu usage (X server uses 44%, kwin around 30% and plasma the rest 20%). This makes the whole feeling of kde4 sluggish and not smooth. If i kill plasma and do the same fast move of the window, the motion is smooth, very fast and cpu usage is 50% for kwin and 30% for X. But i don't care, because everything is smooth. 

But when plasma is running things are not smooth.

In case of machine specs are needed: Athlon XP 1800+, Nvidia Ti 4600 (legacy drivers).

Comment 3 George Goldberg 2008-07-05 08:26:57 UTC

I'm using svn trunk r827914. Following the steps in the origninal report and comment #2, I can't reproduce any particularly high CPU use or slowness. Can anyone still reproduce this using either a beta release of KDE 4.1, or svn trunk?

Comment 4 Thomas Georgiou 2008-07-05 18:22:06 UTC

Performance issues have been fixed by qt 4.4 and kde 4.1