I’m trying to build lighting for my scene and after one hour its at 4%. The process alone is using up 70%+ of my I5-6600k and 12gb (out of 16) of ram. Only 3% of my GPU is being used at the moment while the rest of my system is overloaded. Is there any way to build lighting off the GPU? … or both?
I found this forum thread about the topic. TL;DR For most users, GPU solutions for light building are not practical due to memory limitations (transfer rate as well as capacity), so Unreal uses a CPU algorithm.
There’s also a networked server farm available for light building. You might want to make sure that’s enabled. Otherwise, I’m going to guess something in your level is causing a bottleneck.