The Expanding Ecosystem For GPU Computing

We get better performance writing CUDA code directly than OpenCL, and it's easier for us to develop and debug.

Yes, it's "proprietary" but we need to get our job done.

The difference in momentum stems from a difference in design paradigms. OpenCL is just a library that you can link to can compile using GCC. Because the code you're writing is C++ syntactically you're often jumping through a lot more hoops. Nvidia uses their own compiler, so when you're writing cuda programs you have something that looks a lot like C++, however they have the freedom to extend the syntax to ease development. The marketing arm of Nvidia, combined with the ease of use helped get Cuda the defacto research platform. Once that ball was rolling, it becomes easier to find cuda teachers and cuda examples so it's naturally become more prolific.

AMD's software quality is not so great compared to Nvidia. Rich Geldreich's post, http://richg42.blogspot.com/2014/05/the-truth-on-opengl-driv..., is revealing.

I know Theano has had OpenCL support in the oven for quite a while now.

But it's hard to justify investing heavily into OpenCL when all the serious deep learning labs have already sunk $X0,000 into buying NVidia Titan cards by now. To these people (who are the stakeholders), OpenCL wouldn't add any benefit.

CUDA came out first and was really good, IMO. OpenCL is also really good, but doesn't get as much love from NVIDIA. NVIDIA really hypes CUDA and when they add features, they add them to CUDA first (and OCL never in some cases).

See my other comment for more - https://news.ycombinator.com/item?id=10554601

Meanwhile NVIDIA also seems to have really good marketing behind their GPU software stack. Lots of people who use CUDA have no idea that OpenCL exists and no idea that porting between CUDA and OCL is not super difficult. (It's been years since I've looked at CUDA it might have diverged more significantly since).

AMD's stability (on linux at least) is pretty poor. I don't know if it hurts adoption much, but it can't help.

Also, AMD absolutely dominates on integer workloads which is why it had been used so much for cryptocoin hashing machines prior to the widespread availability of ASICs for most algorithms. On floating point workloads, NVIDIA might do better than AMD, and those seem much more common in science than integer math.

You mean their APUs? They're taking the worst of both worlds (AMD CPUs and integrated graphics) and selling them as a package. They're pointless, imo...

Things have not changed since then.

Here is the author of the book "OpenCL in Action" discussing his problems with AMD's drivers: http://www.openclblog.com/2014/10/amd-and-opencl-20.html

Best quote: "dealing with fglrx is murder. I have never installed an AMD graphics driver without repeated trial and error."

My own impression (using AMD consumer cards for OpenCL on Linux) is that AMD just do not give a damn - their documentation is way out of date, their support in the forums is poor/nonexistent, their installers are just broken most of the time, etc etc.