Xraytrace documentation

Graphics card use is still in the evaluation phase, so it is reasonable to check every calculation first on CPU (e.g. for a single angle) and then to run the graphics card calculation.

To set the graphics card use on, we can run this command

GPU
1

and by using 0 we would switch it off. If we have multiple graphics cards in the system, we can choose which one will run the calculation, e.g. by using command

UGPU
1

which means that the GPU with index 1 will be used (second GPU in the system, as they are numbered from 0).

As an example, here is the parameter file that was used to benchmark different GPU settings. If we play with CPU and GPU use and number of rays, we can obtain graph like this (depending on actual processor and graphics card speed):

Dividing the CPU time by GPU time we can get the speedup factor: