Canvas.SendWillRenderCanvases allocating a lot of memory

SendWillRenderCanvases is allocating ~90k/frame

I have a very dynamic set of images. I am pooling them but the sprite, matrix, active state etc. are touched every frame. I think if the set of images does not change then the same gameobects should get the same data set but even then the allocations stay the same.

If I pause the game no images are touched and the allocation drops to ~9k, but even that seems high.

There are 4 canvases (3 used to render to texture) and ~50 images in the scene and not much else.

 

If one thing changes inside one canvas, all graphics in that canvas are rendered again.
If you separate static things from things that change often with (sub-) canvases you can increase performance. Maybe it is even a good idea to separate the changing canvases more and pack things together which also change together...

 

The problem is that everything is changing all the time.

I think I was a bit tired when I posted so I forgot my actual question.

What is allocating the memory and is there any way to reduce it?
Currently GC is triggering every few seconds which is pretty annoying.

 

When I disabled Pixel Perfect on the canvas the frame rate drop went away.