I’m working on an animation, so part of my workflow is running a windows batch file that calls blender to render the frames I need in headless mode.
When I try switching to 2.8, I find that Blender uses only my CPU, not my GPU. While rendering, my CPU usage is pegged at 100% and my GPU is basically totally idle.
However, when I run Blender 2.8 in regular GUI mode and render the same frames, it uses my GPU like it is supposed to. Yes, I’ve checked that my GPU (GeForce GTX 1080) is properly set as the CUDA device.
I’ve determined that it is not a specific file, because the same behavior is present even for a new file just containing the default cube, a camera, and a light.
When rendering headless from the command-line, Blender uses only the CPU
When rendering the same frames of the same file from the GUI, Blender uses the GPU like it is supposed to.