Any way to get 5.3 to run at same speed as 4.26?

So I have tried porting my 4.26 project to 5.3.2. But it runs slower. In 4.26 I get 70 fps with
4000 draw calls and 6 million polys in 4.26 and 17fps with 1.3 million polys and 2500 draw calls for the same view in 5.3 ( both in game pie in a window, fullscreening doesnt make much difference ). Now my landscape isnt quite optimized yet, in as much as I have 3000 rocks which could do with something better than than just being placed in the top level, and I still need to bake the landscape lods. Having said that I think it is the landscape in 5.3 that is murdering performance. When I load in 4 or 6 landscape tiles in 5.3 the frame rate in editor drops to 50 or 40 fps from 120. Though oddly it can get upto 70 fps when I look around, but once in “play in editor” pie it drops to 17 fps. One other thing in 5.3 currnetly most of my blueprints dont compile , though I cant see why that would slow it down. It just means I cant move my character around when dropped into the world.
My pc specs are an amd 5900x, 32gb ram and an amd 6800 graphics card. My screen res is 2560 by 1440

So I am using world composition. I have nanite turned off , I have lumen disabled ( Global Illumination None, Reflections Screen Space. I have antialising set to TAA and MSAA set to off or 0). I am currently using the defered render in both ( I.e. forward shading is unticked)
I am using shadow maps rather than virtual shadow maps. I dont think I am using any virtual textures. Though it is enabled, I just tend to convert any that load in as virtual textures back to regular textures). I think I have one directional light + skylight (BP_LightStudio) in the world.

tldr :- 5.3 gives me 17fps with nanite and lumen disabled which is a bit pants. I would like to get the 5.3 version running at the same rate as the 4.26 for the same scene. I would say the lighting looks a bit better in 5.3, I dont know if this is related. I have hardware raytracing disabled, I think I dont have raytracing on though not quite sure how to tell .
Anyway any tips for the same performance for the same scene would be appreciated.
Anyone else having bad landscape performance (World composition or world partition) with 5.3 ?

Check with the stat unit, stat unit graph command which part of the engine is struggling. Is it the frame, game logic, draw
renderer (rhi)

Perhaps the uncompiled bps are hurting the game logic loop?

In 4.26 using stat unit ( thanks for the tip) frame is 14 ms and game is 12 ms (in pie) . In 5.3 frame is 57 ms and game is 26ms (in pie) (both of which are horrendus!). Though just in the editor ( same window in 5.3) Game is 20 ms and frame is 15ms .

You could use unreal insights to get a deeper view into the processes.

I remembered I had monster console tools ( which gives some console commands as buttons) so I installed that and found under physics that it said cloth was 59 ms. So I have removed all test skeletal mesh actors I had hanging around in my level and in 5.3 in the same view / window as before it is now something like 80 fps and 12ms in pie, which is a lot more like. I guess unreal 5.3 doesnt like cloth or something ?? Anyway thank you for your help

Maybe the cloth has more parameters that just require some tweaking or they didn’t survive the migration that well :P.

Glad to hear the project is salvageable.

I think you are probably right. I guess something in the conversion from Physx to Chaos physics. Though it will be quite some time before I bother figuring out what ! It might have had something to do with substepping even, which I think behaves differently in chaos physics.

Try recreating the cloth freshly in 5.3 and see if it has ok performance.

Ok so I think I found my problem mesh as a member of the medieval npc pack. I tried a few others from the pack and the worse one was SK_Cook_Skin3. So in 4.26 it pretty much runs fine and doesnt slow the framerate and in 5.3 it literaly slows the framerate to less than 1 frame per second like 1100 ms per frame! This was before and after downloading the update (and overwriting the original files). I guess cloth isnt 5.3s strong point ! I dont know anything about cloth and cant be bothered to learn it, so I am reliant on working assets! I guess I wont be having too many cooks in my game !
I guess the one other thing I would say is that adding assets to the editor window like loading landscape tiles or adding skeletal meshes does slow down the play in editor session (pie) more so like 20 to 25ms instead of 12 to 15 ms if the level is started without loading in the assets to the editor first !

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