Ask Ubuntu is a question and answer site for Ubuntu users and developers. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have a test suite that uses openCL and I notice that I pass more if I close down everything and just run the tests. I fail more if I have lots of programs open on my desktop. Is it possible to cap how much vram my displays are sucking up?

share|improve this question

migrated from Feb 2 '11 at 11:56

This question came from our site for professional and enthusiast programmers.

Is compositing on? Do you have fancy shadows, translucency, etc? Try turning compositing off. – 9000 Feb 1 '11 at 19:19

Stop using a compositing window manager. They use the GPU for their special effects, which means that in addition to the framebuffer in VRAM, every window is backed by a texture in VRAM and shaders are used to render the desktop. If you use a simpler window manager with no fancy or 3d effects there should be less contention for your GPU resources.

(Some compositing window managers can be run with compositing features disabled, so try that before you go shopping for an entirely new window manager.)

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.