Are the two contexts required? Will rendering not occur while the DMA transfer is proceeding, unless I do the upload in another thread, even with last-gen NVIDIA cards? If so, how does that make sense? It seems an artificial limitation, as the hardware obviously can handle it (even in the single copy engine consumer-level cards) if you have another thread.
(If it matters, I'm using persistently mapped PBOs.)
Edited by Prune, 13 May 2014 - 05:15 PM.