Systems hangs while any openCL activity is running (not just the display)

Discussion created by bjano on Apr 3, 2011
Latest reply on Apr 5, 2011 by trinitrotoluene


I have a 32-bit ubuntu 10.10 system using the 2.3 sdk,  with a h5670 and an intel CPU.

My problem is that when I start any opencl stuff, the system halts completely until the gpu is finished. I have read the recent similar thread, this situation is different in that not only the display stops working, but absolutely everything. The most obvious is that the music stops playing in the background which should have nothing to do with the video card. Also, I can't stop a running program, as the mouse and keyboard are not responding. When the program is finished, everything is back to normal.

I am not using any OpenGL in my program,  and I tried a few sample codes (NBody for example) and they don't hang the system.

What could be causing this?

I was wondering that perhaps the opencl library decides to run the kernels on the cpu and this causes it to be not able to deal with anything else, but I have already checked a million times that the gpu's device ID is selected.