Lightmass build stuck at 0%, UnrealLightmass logs fill up HDD, Swarm crashes

Hello all,

The title pretty much says it all, I’m having a weird bug where for one specific level in my project, the Lightmass refuses to build, and has been stuck at 0% even after building overnight (12-14 hours), the lightmass logs start clogging up my HDD and then Swarm crashes.

It’s a somewhat large level but all the lightmaps are of low resolution (64) and there aren’t THAT many meshes or any foliage at all so I’m confused as to what the issue is.

On top of this, the Lightmass itself doesn’t be seem to be building because all that happens is that the Lightmass logs folder (“Engine\Programs\UnrealLightmass\Saved\Logs”) keeps getting bigger and bigger, and my hard drive eventually runs out of space.

I’m inclined to think this might be a bug of some sort. Will try reinstalling the engine and see if that helps.