normaly I have 120-150 FPS, but when I enter 40 people battleground, FPS drop to 30-50
I did alot testing, and found out the portrait element is causing this
when I disable portrait, FPS return to normal
is this normal or I miss something?

my portrait related code

local function PostUpdatePortrait(element, unit)
	element:SetDesaturation(1)
end

if C.unitframes.portrait then
	local Portrait = CreateFrame('PlayerModel', nil, self)
	Portrait:SetAllPoints(Health)
	Portrait:SetFrameLevel(Health:GetFrameLevel() - 1)
	Portrait:SetAlpha(C.unitframes.portraitAlpha)
	Portrait.PostUpdate = PostUpdatePortrait
	self.Portrait = Portrait
end

You might want to tell us what unit frames you are putting those portraits on. 3D models in the 2D UI does come with a performance cost.

Is this player, target, all the raid frames, nameplates...what? :)

As a general rule I would avoid putting anything like this on frames there are very many of, like nameplates or raid frames. Only singular targets and smaller groupings like boss, arena, party works, really.

@Goldpaw yes, I use this on party/raid frame, so I guess I should only use this on player/target frame 😭

I do not have this issue with my party frames with 3D enabled. Show us or link us code we can overview.