Multiple GPU running

[snownus]

Does this code work on multi-gpu?

[arcelien]

This would be dependent on Ray's PBT implementation's support of mutli-gpu. When I tried in Feb/March of this year, there were some issues which may have been resolved.

[richardliaw]

I think this should work fine! Please try it out on multiple GPUs, and if you find any issues, please raise it on ray-project/ray.