In my 3D game I have some 2D objects that get instanced a lot. to be specific, I am instancing several labels that display damage numbers above a 3D enemy's head every time they get hit. These labels are Sprite3D 's with a view port that houses the labels. If something like a shotgun blast that instances several of these labels hit's an enemy, I get a small freeze and frame rate drop. The drop is about 5-6 frames but I can see the game freeze for about a tenth of a second! not ideal.
I looked into it before posting this question and found that using mesh instances (quads and planes) were much more efficient and better for performance. BUT, when I made the switch the performance was EVEN worse. I now had a drop of 30 fps!!! and the game slowed to a crawl. I also heard that setting the render to 2D was best for performance with the view ports, but also to my surprise they actually run better in 3D.
Perhaps I am misunderstanding something.