Performace dropping

Hi,
So recently I’ve started experiencing a significant performance drop since I started lighting my scene. It was sitting at a comfortable 120 fps and sometimes dropping a little bit, but not really anything too noticeable. But now it’s reaching at most 60ish and hanging around the 40’s. I tried deleting all of the lights and it increased it to 80fps. I’m using the moveable lumen settings on all of my lights and all the meshes are using nanite since everywhere online was saying to enable nanite where I can as it works best with Lumen. Any ideas or better practices I could take would be greatly appreciated! :slightly_smiling_face:

Are the lights stationary or static?

Try reducing the attenuation of the lights. If they overlap it might lower performance.

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Lights are heavy if you use many close together. From what I can see you are not using static lights. If you want to optimize the game further, I suggest to make the lights static.

Hey @EliasWick!
So when would I want to use Lumen lighting methods over static. I know moveable makes dynamic shadows but I thought lumen would make dynamic lighting less expensive since moveable lights were a thing back in UE4.

The only way that i know to make with lumen lights less expensive, would be to use emissive as a light source. Also turn shadows off or use distance field shadows to reduce the cost. You could also try spot lights instead of point lights which are 6 times cheaper than point lights.

The best way to see what cause the performance drop would be to see it on the gpu profile or use the stat gpu command.

What fps should I be expecting to get in the editor? I know it’s not going to run as smoothly as I’d like because it’s in the editor, but is it normal to be dropping below 60 consistently when running the game? It doesn’t look very jittery, but I don’t want to export the game and notice that the fps is still dropping severely because I just wasn’t optimizing correctly. If there’s anything else I can do to help optimize my level, let me know. And I have a mix of exterior lighting using the directional light and all that and interior lighting in my basement which I’m probably going to have the most trouble with as I’m not sure how to make the lighting look realistic because the lights don’t illuminate the entire rooms if their attenuation is too small.