Desktop runs very slick, animations are all fast and flawless. Moving windows around, however, is very laggy. Why?

This isn't a question about Ubuntu being laggy in general - not at all, in fact, it's very slick and fast for me. Clicking the "Workspace Switcher" in the dock performs the animation immediately and very smoothly. Switching between workspaces with the arrow keys - again, flawlessly.

My computer has a resolution of 2560x1440 on a 27" display (no, not an Apple product - though my monitor has the same panel that Apple use in their cinema displays). It's powered by an Nvidia GeForce GTX 470 - easily enough to handle it - and an Intel i3. Hardware is not the issue.

I am running Ubuntu 11.10 (upgraded from 11.04). I had the same issue in 11.04.

I'm running the "NVIDIA accelerated graphics driver (post-release updates) (version current-updates)" from the additional drivers dialogue. Two drivers have been suggested to me via that dialogue and I've tried both - same effect with each. The driver is "activated and currently in use".

Any other information required, let me know and I'll post it. I'm a programmer who works with Linux daily (both as a job and as an interest) so technical instructions are fine.

I've noticed that Compiz uses a lot of CPU when moving windows around and it's memory usage is relatively high (though possibly expected for Compiz):

1671 user 20 0 478m 286m 33m S 1 7.3 12:44.05 compiz

And one more thing - occasionally moving windows around is fast. But it only happens when all applications are closed, and even then it sometimes doesn't. Something must be interfering, but what? I'll try and find out but in the meantime, any suggestions are much appreciated :-)

I don't know why this happens, but the following worked for me:

...

I've changed my mousepolling to "10" which has solved this problem.

Instructions for anyone who would like to replicate my solution:

sudo gedit /etc/modules

Append the following:

-r usbhid
usbhid mousepoll=10

Save the file and reboot. To verify that the setting is in effect, run the following command:

cat /sys/module/usbhid/parameters/mousepoll

If the result is "10", you have succeeded. You should also now have smooth window movement.

^Source

I have the same issue and I've been troubleshooting it for some time time. Turning off V-sync in compiz and nvidia-settings does help a bit, but it doesn't solve it entirely nor do I think it's the cause of the problem. And when I check PowerMizer, everything looks ok. It is set to Maximum Performance (Performance Level 0), so I doubt this is the problem.

You can try to manually add the following line to the Device section of /etc/X11/xorg.conf:

Option "RegistryDwords" "PowerMizerEnable=0x1; PerfLevelSrc=0x3322; PowerMizerDefaultAC=0x1"

Just make sure that the indentation is the same as the other lines in there.

When I recorded this behavior I noticed that the mouse in the recording moves around normally while on screen it was freezing just like the rest of the desktop. Not sure if this helps, but thought it might be worth noting.

I have come to the conclusion that this gets worse over time. It is all fine right after boot (or restart of Compiz or X). But after a while it gets more and more sluggish until moving windows around will more or less freeze your whole desktop (like in screen cap) until you stop moving it. Memorly leak perhaps?