What is exactly Canvas.RenderOverlays ?

Unity Engine
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1

Hi,

My game used to be really fast, like 200 fps, It was before i upgraded to 5.6.1f1.
Now it barelly reaches 60fps.
When i see what could cause that in the profiler, i got the famous, waitForPresent that eats up a lot.
But when i enable GPU profiling, i see that Canvas.renderOverlays should be the one causing the lags.

Enven stranger, when i disable all my UI elements, i still got those spikes !

So: What is exactly this Canvas.renderOverlays ??

thx.

2

pump

3

the best tip on this I remember is separate moving (rotating/scaling) elements from fixed elements, so at least 2 canvases. this is because each time an element transforms, the whole canvas is refreshed.
might this be the issue?