This mod gradually "turns off" all entitites on surfaces where there are no players.
Perhaps, it works kinda clumsy but it'll improve UPS for mega-bases if you'll use several surfaces etc.
It effective in singleplayer, however, use it cautiously in multiplayer. There's no point to use this mod if players are active on all surfaces or you don't wanna "freeze" entities on the surfaces or you didn't use new surfaces.
- /add-surface (adds new surface/world)
- /surfaces (opens UI for surfaces (select a surface to teleport there)
- /delete-UI (deletes UI of this mod)