Really slow performance in blender 3.3.0. in relatively simple scene


This is not a new issue to me.
But I recently got a new computer, and I thought would speed up the viewport performance.

12th Gen Intel Core i9-12900KF 3.19 GHz
Geforce RTX 3090

I am currently working on a scene with these stats:
Faces: 116,878
Objects: 35
Memory: 1.68 GB
VRAM: 1.8

When moving objects around, I get around 1-2 FPS.
This is unworkable as I’m trying to animate stuff.

Wireframe mode is as slow as Solid.
I have applied or switched off modifiers in realtime view.
Some objects have shape keys, but the issue persists when toggling them off.

I have disabled all unnecessary add-ons.
The scene contains more objects, but they are in collections that are excluded from view.

Any tips to speed things up?

Hi, Try simplify with subdivisions set to one or zero.

Are there any simulations or physics in the scene? Any complex rigged character?

Does it happen only in Blender? If you have a new computer, something about it could be wrong, so it could be a good idea to check some other program or any game that’s graphically intensive.

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It worked surprisingly well.
But it’s weird as the objects I tried to move hade no subdivision modifiers on them.

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If I understand correctly, objects with modifiers are re-calculated every frame even if they aren’t the ones you changed. In the case of subdivision modifiers, this will be especially noticeable if the objects are on screen, because they will also slow down the viewport. If you have objects that need heavy subdivision, it’s good practice to set their viewport level lower (that’s why the modifier has a viewport level and a render level).

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But there is something fishy in his scene or with his Blender version, there is no reason for such a slowdown. Especally not since he has a beefy machine that should have a ton of processing reserve.
As we speak, I have a scene open in Blender 3.2 with 1.2 million polygons.
A 3D scan with half a million polygons and a plane with a Subd modifier. Both meshes are duplicated with an array modifier.
I can move both meshes in my scene without any visible type of slowdown - looks like 60fps.
While shaking these models around in my viewport, I took a look at my GPU/CPU stats in the Task Manager:
8% CPU, 38% GPU.

My computer (Ryzen 7 3800X, RTX 3060) shouldnt outperform his with ease and with such an order of magnitude.
Something is very wrong.

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I agree, there is something we don’t know here. He mentionned more objects in hidden collections, maybe they could be in cause? That’s hard to say without seeing the actual file.

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Yeah, as a countermeasure I would copy and paste and isolate these objects into a new scene and see if the problem is still there. Maybe even try another Blender version.
I occasionally experience weird slowdowns with files/scenes that completely go away when I throw all of it into a fresh Blender file.

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each object is 1 draw call, each material per object will add another.

if you want a smoking fast scene try and use 1 single material and a texture atlas.
and as many static elements joined as possible*

also be aware we can use geometry nodes to cull unseen faces.

the upbge branch has ‘LOD’ as well.