No GPU devices found... But yesterday everything worked...

Yesterday everything worked perfectly. But today, no GPU devices can be found and I haven’t altered the code! I use PyOpenCL and the following code to find GPU devices:

pl = cl.get_platforms()
devs = pl[0].get_devices(cl.device_type.GPU)

In the above code “devs” is for some reaseon an empty array.
There is only one platform returned: “<pyopencl.Platform ‘Apple’ at 0x7fff0000>”

I have no idea on how to debug this. Can anyone help?

Problem solved. I was accessing the machine (a mac) using ssh, and apparently the user also needs to own the desktop session to access the GPUs. The problem is explained in further details here: … ely-on-mac