[Foliage] Build lightmass - computer freeze

my computer has 16GB RAM.

I painted about 5000 trees on my level and then run building light… Immediately RAM up to 15,9GB and my computer freezes :frowning: Lightmap resolution scale down and increase windows virtual memory didn’t help me. Level dimensions is only 512x512.

Only lightmap building is problem. When I run game without building lightmap I have 110 FPS because I’m using LOD and culling but building lightmap no using culling and tryng import all level to RAM…
How can I solve this? I can waiting longer for lightmap build ending but it shouldn’t freeze my computer…