OpenCL can select discrete GPU by default?

[DickyQi]

I have Old MacBook Pro with one intel GPU and one AMD discrete GPU. I am using OpenCL ggml, and ggml default choose Intel GPU. I hope ggml can using discrete GPU by default, or we can set GPU device though API?

[SlyEcho]

It is possible to select the OpenCL device with an environment variable:

export GGML_OPENCL_DEVICE=1
./main ....

You can use numbers 0, 1, 2 ... or you can use string matching, like GGML_OPENCL_DEVICE=AMD but what strings to use depends on what info the OpenCL platforms give. You can use the clinfo command to see what is there.

[SlyEcho]

Actually, I need to write the documentation for this part. It doesn't seem to be anywhere.

[jp-aa]

Actually, I need to write the documentation for this part. It doesn't seem to be anywhere.

Is there a way to do this for cuda devices? I have no idea how to tell it to use my other gpu

[SlyEcho]

Is there a way to do this for cuda devices? I have no idea how to tell it to use my other gpu

• CUDA: CUDA_VISIBLE_DEVICES
• HIP: HIP_VISIBLE_DEVICES with ROCm Port #1087

You just list the devices that are visible to the application:

CUDA_VISIBLE_DEVICES=1 ./main ...

[SlyEcho]

README now should have info about GPU selection for CUDA and OpenCL.