I notice I am confused how the code needed for the GPU to sleep was implemented.
It was failing when simply saving/copying gigabytes of flat memory, but on the other hand it was able to recover successfully the previous complex hw and sw state and data structures?!
I guess it probably makes sense if after waking up that data is actually dropped and the gpu and ui is reinitialized and redrawn.
As I understand if the GPU fails to save VRAM it drops the RAM copy(?) before restoring the GPU data structures or abandoning sleep entirely. But if it saves VRAM then crashes after the GPU is suspended, it will often fail to wake up the GPU, resulting in no monitor signal. Though I'm fuzzy on the details (and the order of operations depends on which kernel you're running).
