Nvidia/AMD asynchronous stuff, whats happening?
https://www.reddit.com/r/pcgaming/comments/3j1916/get_your_popcorn_ready_nv_gpus_do_not_support/
Simplified explanation:
Think of traffic flow moving from A->B.
NV GPUs: Has 1 road, with 1 lane for Cars (Graphics) and 32 lanes for Trucks (Compute).
But it cannot have both Cars and Trucks on the road at the same time. If the road is being used by Cars, Trucks have to wait in queue until all the Cars are cleared, then they can enter. This is the context switch that programmers refer to. It has a performance penalty.
AMD GCN GPUs: Has 1 Road (CP; Command Processor) with 1 lane for Cars & Trucks. Has an EXTRA 8 Roads (ACEs; Asynchronous Compute Engines) with 8 lanes each (64 total) for Trucks only.
So Cars and Truck can move freely, at the same time towards their destination, in parallel, asynchronously, Trucks through the ACEs, Cars through the CP. There is no context switch required.
NV's design is good for DX11, because DX11 can ONLY use 1 Road, period. GCN's ACEs are doing nothing in DX11, the extra roads are inaccessible/closed. DX12 opens all the roads.
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now