Can you explain a little more please. I thought that graphics processing would revert to CPU if the GPU is maxed out and so swap might ultimately help? Is there no general GPU-swap mechanism? If CPU threads are competing for GPU resource does the GPU getting paged-out?

I suppose this could be an historic thing, GPUs can have a type of DMA now, and disk access is much faster too, so paging perhaps makes sense when it didn't before?