Slate RT Draw Batches Slowdown

KelpRings · February 2, 2019, 8:56pm

I have just updated from 4.20 to 4.21. On 4.20 my system runs 60-70 fps steadily, but after updating to 4.21 I can’t get above 35fps, and it usually sits around 24fps. Playing a game is even worse.

Stat Slow shows that this seems to happen around “Slate RT Draw Batches.”

My assumption is that maybe 4.21 is heavier on the GPU and my laptop can’t handle it, but I don’t think the update should have such a crazy framerate drop.

Does anyone know why it might slowdown like this or know how I could find out more about the slowdown?

I know this might be a very specific question, but I’ve searched the forums and documentation for 3 days and have come up with nothing.

Any ideas?

mChen47 · October 22, 2019, 9:59am

hi Ryan, got any solution? I encountered the same problem.

KelpRings · October 22, 2019, 3:00pm

I wish I had a good answer for you, but luckily this problem solved itself after updating to 4.23.
Are you having the problem on the most recent version?

KelpRings · October 22, 2019, 4:18pm

link text
This was the most helpful thread I found, although it did not provide much of a solution. It seems like the hardware just can’t keep up with the scene.

anonymous_user_1af62794 · July 20, 2020, 10:18am

Have you ever tried the below command?
Slate.EnableGlobalInvalidation 1

From 10 ms slate frame time I reached less than 1 ms!

This will redraw UMG widgest just when they are changed.
Do not use any bindings because they will not work with global invalidation.

Another alternative to enable global invalidation is through cpp code:
FSlateApplication::Get().ToggleGlobalInvalidation(true);