Plan: BO move throttling for visible VRAM evictions

[Christian König]

Am 18.05.2017 um 10:17 schrieb Michel Dänzer:
> [SNIP]
> One thing that might help would be if we could swap individual memory
> nodes between visible and invisible VRAM for CPU page faults, instead of
> moving/evicting whole BOs. Christian, do you think something like that
> would be possible?
I've looked into this while working on splitting VRAM allocations into 
smaller nodes and the answer is nope, not at all.

We would pretty much need to rewrite whole TTM from BO based to page 
based. Otherwise you just have way to much overhead with all those ttm 
objects around.

And when we really want this step I would rather wait for HMM to land 
and use that instead.

Christian.