> Although presumably this only applies to a small fraction of the VRAM?

They did mention they saw 4GiB of eviction for a single 32MiB scan out image.

So while I would call the image allocation small, it seems to cause an avalanche of evictions. Amplified by the fact that each frame has one of these images, though I expect subsequent frames might have a better chance of already fitting into evicted space.

What I don't exactly understand is: doesn't it make sense to always reserve the contiguous physical memory for this case and not allow anything else to be put in it?

Or alternatively, instead of evicting it all, can you move the data around in physical memory while updating the page table, so that you can clear a large enough continuous block of physical memory?