On and off errors when creating thread

[mfeldt]

Apparently sometimes thread creation in the opnCL context fails with the below error:

FFTthr = FFTapi.Thread.create()
File "/home/feldt/AOSAT_Dev/venv/lib/python3.5/site-packages/reikna/cluda/api.py", line 240, in create
selected_pnum = sorted(devices.keys())[0]
IndexError: list index out of range

The strange thing is that after a few attempts it sometimes works, and once the thread is created successfully it usually works flawlessly. So I suspect it has to do with an underlying library trying to connect to the GPU or something. The question is however - could reikna diagnose the problem and give a more useful report?

OpenCL version is OpenCL version 2019.1.1, reikna version is 0.7.2

[fjarri]

Can you reproduce this with pure PyOpenCL? It seems as if sometimes get_devices() method of a Platform object does not return all the available devices.

[mfeldt]

I'll try when I find the time. Right now the main problem is indeed that it happens only sometimes...