We need to run several instances of an application on a Linux GPU server and be able to choose the GPU each instance renders to. The application is created with Unreal Engine 4 (4.15.1) which uses SDL, and the server is an Ubuntu 16.04.
So far with other non-SDL applications we could achieve this by configuring virtual X displays with
nvidia-xconfig, each of them attached to a different GPU. Then using e.g. DISPLAY=:2 to select the display.
However, with this one we get the error "No available displays" in SDL_Init. Somehow is not recognising any display.
Also, we are able to run it without the X display (DISPLAY unset), but then we are unable to choose the GPU.
Any ideas what can be failing or how can we solve this?