Hi,

I am writing my own engine on C# using .Net core 3 and I wrapped macOS window to output my triangle demo there and it actually render, BUT....

I receive only ~140 FPS. I investigate a little and found out that calls to 

vkCmdEndRenderPass(), vkEndCommandBuffer() and vkQueueSubmit()

takes toooo long and I have no idea why, but this is not the end.

Most interesting thing start when I swipe to another virtual screen on my mac and right after that FPS becomes ~5000 (which is actually it should be always)

And when I come back to screen where my window renders, FPS again becomes 120-140.

I use MoltenVK and Vulkan SDK version 1.1.121 and I dont have such strange behaviour on windows.

Obviously this is not normal. Does somebody knows why this can happen and how to fix that?