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CUDA - warp and OpenCL - wavefront

Question asked by sajis997 on Apr 23, 2013
Latest reply on Apr 23, 2013 by LeeHowes

Hi forum,


I believe that some of you in the forum had gone through the book "Heterogeneous Computing with OpenCL" . I am going through chapter 5 of its 1st edition.


And  bit confused with the association of cuda warp and opencl wavefront.


In CUDA, once a block of threads is assigned to streaming multi-processor, it is further divided into 32-thread units called warp. So conceptually , a warp contains 32-thread units. It is according to the book "Programming massively parallel processor"


In OpenCL, according to the book, "The best example of this is on the GPU, where as many as 64 work items execute in lock step as a single

hardware thread on a SIMD unit: On AMD architectures, this is known as a wavefront, and on NVIDIA architectures it is called a warp. The result is SIMD execution



According to the book, a warp contain 64 threads.



Which one is right ?


Please let me know if i missed anything or misunderstood.