Re:A Taste of GPU Compute [video]
by jdashg on Friday April 17, 2020 @03:22PM
(#22902087)
There's a bunch of intractable latency, but there are patterns that can help maintain pipelining, if you don't need the data immediately: https://developer.mozilla.org/en-US/docs/Web/API/WebGL_API/W...
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Right, but if I go closer to the metal how much of the latency is really truly intractable? 100 microseconds? 1 millisecond? 10 milliseconds?
Can't speak for WebGL APIs, but in OpenGL (and other C++ graphics/GPGPU platforms), it is certainly possible (and necessary) to write fully interactive real-time apps that rely on a few rounds of communication between GPU and CPU code every frame. At 60 fps, you have 16 ms per frame. As long as you aren't copying huge arrays back and forth, I'd say you can budget in the 1 ms order-of-magnitude per data transfer.
I don't know much of that would be avoidable if you were actually closer to the metal than the raw OpenGL C++ API call