Level streaming Performance Question

Hello to Everyone,
I have a question regarding the streaming level performance. I wont to know if load and unload sub level is gonna to optimize the drawcall and the relevant performance issue comparing with a unique big level, or if it is just an instrument to better optimize the work just ffrom logistic point of view.

Thank you in advance

Something thats not in memory doenst have to be optimized away.

I think using level streaming will help you organize/designing your levels better + you dont have to worry much about memory consumption since the level data is streamed in when needed.

Sorry but I’m bit confused. If I understood well the streaming level option is just used for better organize the work, why is present the function of level stream volume in order to load and unload portion of the level during the game?

No, level streaming allows the engine to avoid creating everything at once in the scene when it loads, this helps the engine to have better performance, for example, if you create 10 houses, each with 200 objects, at start the engine has to load 2000 objects; but if you use level streaming, at start it Will create just 10 houses and nothing inside, so you save a lot resources, time and even FPS because the engine doesn´t need to create 2000 objects, shadows, etc.

Now when you get inside the first house, you make a trigger to load only that house´s objects (level 1), meaning 200 objects Will load when you enter that houese and when you leave that house it Will hide them (unload that level), then you enter second house, again and again, so you always have 200 objects instead of 2000 from start… multiply this example for an scene with 1,000,000 houses instead of 10 houses, just imagine how many time it Will take the engine to create 1,000,000 houses with 200 objects inside each…. omg your game Will crash every time LOL, that´s why Level Streaming is a must have!

ok i understood.
Thank you for the clear explaination