OpenCL, CAL/IL & MultiGPU

Discussion created by afo on Mar 16, 2011
Latest reply on Mar 17, 2011 by afo
Switching from OpenCL to cal in multigpu (2xHD5970), new issues

hi all,

After switching from OpenCL to CAL/IL to be able to use the 4 GPUs I found an issue related to which GPU is running the kernel:

In my application (single context ,single thread) the GPU to use is a parameter; when I use GPU 0 or 1, my application runs for 55/60 seconds; the same application using the same dataset using GPU 3 or 4 runs for 75/90 seconds. In all cases there is only one GPU running and is the same application running in the same terminal (I am using LinuxX86_64-OpenSuse11.2).

Is there an explanation for this? Has someone seen something similar? Any insight about this will be very appreciated

best regards,