Serious performance drop on 4.15

[theknoppix]

Hey all,

I've just converted a project from 4.14 to 4.15. Kite assets couldn't be converted so i re-download new version of it and replaced on project. But now the problem is my fps dropped from ~90 to ~10. Everything "Dynamic" on gpu profiler takes around 20-25 ms, DBuffer also. I almost checked everything, reset settings of the rendering from project settings. Disabled DBuffer but still "Dynamic" eats a lot of performance. Even though i delete directional light (only light in the scene), "Dynamic" still eats 20ms. Scene uses kite demo assets.

I'm attaching an image to show difference and gpu visualizer screenshot. I hope someone can help me about this problem.

https://dl.dropboxusercontent.com/u/...nceProblem.png

Thank you.

[Chosker]

I don't have direct comparison shots but I just updated my project from 4.13 to 4.15 and also noticed a considerable GPU-bound performance loss (both running the game and just in editor).
my scene is a big landscape with grass and a few foliage assets.

I'll need more time to investigate and I probably won't do it now (this is only on my side project, my main project is in UDK), but my FPS dropped from ~40 to ~20

[MikeRPG]

You sure there isn't something in the projects settings' rendering that you changed in 4.14?

[theknoppix]

I found the reason. Someone from unreal slackers told me to check lod screen sizes on static meshes and that's the issue. When you migrate assets, some of the static meshes come with broken lod screen size. All of them are 0, so engine shows LOD0 all the time. You can compare triangle count with old and migrated project by using "stat engine" console command, and you will see higher triangle count.

I reported the bug on answers. Here is the link:

https://answers.unrealengine.com/que...ug-report.html

[Treadport]

IS it possible to fix this? because I just updated to windows 10 and now 4.15 is the only version that compiles my project, but I can't use it with this problem.