(bug) Slow down with Magic Mask in Fusion 19.0.3-19.1

Is anyone is experiencing a big slow down with the Magic Mask in Fusion with 19.0.3?
It's starts good, then it does just 1 fps. The ram is just at 25% (I have 64Gb of memory).

The Gpu is a 16%-26% and the VRAM is at 17 (on 24)

It process 360 frames very quickly then it's just impossible to work with.

The color page is unaffected.

I opened up Fusion Studio (19.0.3) and it works perfectly fine there.
I really like these 0.0.x updates adding problems

Nevermind, 19.0.2 (reinstalled now), is the same with the Fusion page.
Cool, we can't use magic on the fusion page of Resolve with more than 300 frames, then it goes at snail pace.

I generally don't use the magic mask on relatively long clip, so I never saw the problem.

Oopos I'm in the wrong forum.. I wanted to post the thread on the Resolve forum.
If someone can move it there?

No progress with 19.1


lol can we have something that is not constantly breaking? then working, then breaking.

The color page has no problem doing the same thing, at 38 fps

What is the videosource like? Sometimes this has an effect on performance. More in the Fusion page than in the color page for some reason.

The video is a regular h264 8bit mp4 file. But it does that on everything anyway (for me).

I forgot to mention that it does that when it's on "better". But faster is problematic too, it takes juste a bit longer to starting to choke.

The thing is, in the past we saw these problems many, many times with tools added to the color page first, then added to the Fusion page. The fusion "version" always had some kind of problems, less optimized.

Here a demo, with Fusion Studio, Fusion page in Resolve, Color page (and I'm screen recording at the same time so it's even smoother on the color page without OBS in the background) : https://jumpshare.com/s/NuD87IzJRlGRzRdK7xET



The video of the demo is 4k at 25fps, on a 1080p timeline in Resolve (and 4k in Fusion Studio)

(Can a mod move this thread to the Resolve forum please?)

Well, this is a quite obvious example. E-mail support with this project/software. This can help them fix it.

Wow, the bug is still there in v20
I have to do some vfx today, I was hoping this was fixed.

20 beta 3, it "seems" to have been fixed.
665 frames with magic mask in fusion with no stutters in my current project.
I hope it wasn't a fluke and got lucky today