Kubuntu 12.04 very slow in performance

[marco07]

Hi Folks:
I have recently upgraded from 11.10 to 12.04. Upgrade went smooth without any problem. All work OK. However my system is very slow in response to any mouse click. When I click on K menu it takes a while for it to open and then it suddelnly disappears. Applications open with a long delay. Firefox scrolling jumps rather than a smooth rolling down or up, etc.
Could somone please help?
P. S. My system is a Gateway DX200S desktop, penT 4, 3.04 GHz, 2gig Ram with Intel 915G/GV/910GL Express chipset family.
Thanks in advance!

[Snowhog]

First, check to see of the Desktop Effect 'Blur' is enabled (likely). If it is, disable it and then restart (log out/log in). The 'Blur' effect is very hard on Intel GPU's, when it works at all.

[DarthMedicus]

I can certainly attest to the misadventures caused by the blur effect. I actually had the same issue as the OP when I upgraded, but I solved it by first logging into another desktop environment to see if it was a hardware issue across the board. When I determined that it was not, I logged out and entered in "KDE failsafe", then looked at my desktop effects. I disabled desktop effects on startup, then logged out/in. Problem solved.

Now I have to go through each one to determine which effect caused the sluggish performance. There is another thread [strike](under this same sub-forum)[/strike] here that addresses "kwin" eating up 100% CPU resources upon start-up that may be of help, as well.

[marco07]

First, check to see of the Desktop Effect 'Blur' is enabled (likely). If it is, disable it and then restart (log out/log in). The 'Blur' effect is very hard on Intel GPU's, when it works at all.

I finally succeeded disabling "Blur" though somewhat difficult with the sluggishness of performance. It resolved the issue of slowness and performance returned to normal speed after re-logging in. Once only I got a warning about "net manager attach" closed unexpectedly which I pressed relaunch button and rebooted the system. So far it seems everything working OK. I also found out that switching to xrender is another solution. For now I stick with the way it is with "Blur" disabled. If I get further warning and/or crashes then I will switch to xrender for good.
Thank you and others for your advice!. I will mark this thread resolved.

[sez]

I have Intel video and found Xrender to be slow. No problems with OpenGL so far.

[pwabrahams]

I've had the experience of disabling desktop effects (including blur) and having my system speed up significantly. But after a while it slowed down again. There's some kind of crud accumulating, I suspect.