> CUDA is designed to run parallel code on NVIDIA GPUs - full stop. Opencl is designed for heterogeneous computing, and GPUs are just one of many computing uni

> CUDA is designed to run parallel code on NVIDIA GPUs - full stop. Opencl is designed for heterogeneous computing, and GPUs are just one of many computing units possible. So not apples to apples. This is really why OpenCL failed. You really can't write code that works just as well on CPUs as it does on GPUs. GPGPU isn't really all that general purpose, it's still quite specialized in terms of what it's actually good at doing & the hoops you need to jump through to ensure it performs well. This is really CUDA's strength. Not the API or ecosystem or lock-in, but rather because CUDA is all about a specific category of compute and isn't afraid to tell you all the nitty gritty details you need to know in order to make effective use of it. And you actually know where to go to get complete documentation. > There are basically two GPU vendors - so vendor lock is practically assured already. Depends on how you scope your definition of "GPU vendor." If you only include cloud compute then sure, for now. If you include consumer devices then very definitely no, not at all. You also have Intel (Intel's integrated being the most widely used GPU on laptops, after all), Qualcomm's Adreno, ARM's Mali, IMG's PowerVR, and Apple's PowerVR fork. Also Broadcom's VideoCore that's still in use by the very low end like the Raspberry Pi and TVs.