Re:AMD Radeon RX 6800 and RX 6800 XT Review
by Const-me on Wednesday November 18, 2020 @02:33PM
(#25141312)
> Doesn't mean that everyone would be fine with just mandating it everywhere
Practically speaking, often I enable it everywhere even on CPU (or similar options in visual C++). When more precision is needed, FP64 is the way to go. Apart from rare edge cases, you won't be getting many useful mantissa bits in these denormals, or with better rounding order.
> So which it is? Depends on the vendor.
Yeah, but on the same nVidia GPU, I'm pretty sure mad in DXBC does precisely the same thing as fma in CUDA PTX.
> just in a way that the DX11 implementation cannot detect
It doesn't detect much. If you want to allow shaders to arbitrarily read and write the same buffer, bind that buffer as UAV and you'll be able to run many of these shaders in parallel, despite a single queue.
P.S. AFAIK the main use case for these queues is high-end graphics, to send relatively cheap GPU tasks at huge rate (like 1MHz of them), from many CPU cores in parallel. In GPU compute, at least in my experience, the tasks tend to be much larger.
Practically speaking, often I enable it everywhere even on CPU (or similar options in visual C++). When more precision is needed, FP64 is the way to go. Apart from rare edge cases, you won't be getting many useful mantissa bits in these denormals, or with better rounding order.
> So which it is? Depends on the vendor.
Yeah, but on the same nVidia GPU, I'm pretty sure mad in DXBC does precisely the same thing as fma in CUDA PTX.
> just in a way that the DX11 implementation cannot detect
It doesn't detect much. If you want to allow shaders to arbitrarily read and write the same buffer, bind that buffer as UAV and you'll be able to run many of these shaders in parallel, despite a single queue.
P.S. AFAIK the main use case for these queues is high-end graphics, to send relatively cheap GPU tasks at huge rate (like 1MHz of them), from many CPU cores in parallel. In GPU compute, at least in my experience, the tasks tend to be much larger.