Seems to be more pronounced when the patch is performance demanding.
From my original patch (which I can’t share), running in 2021.0.4-0321:
Similar behaviour (not as severe) can be observed when opening for example the Instanced Spheres patch from the help browser and increasing the spreadcount (eg. to 6000). The patch is running at stable 60 FPS on my machine, but as soon as I hover an IO-Box or inputs/outputs the framerate starts fluctuating.
Is this being looked at? Makes debugging nearly impossible in some scenarios, since the framerate completely caves. The issue was also quite visible when @gegenlicht demoed his Fuse VAT extension in yesterday’s meetup.
In general there is to say - a frame rate drop is to be expected since some part of the rendering must be done on the user thread. Only there the graphics resources are valid. Accessing them from another thread would lead to an application crash. That being said, there’s probably still room for optimization. Just hard to give a time frame here.