Posted by Arnold on Jan 30, 2017; 7:47am
URL: https://forum.jogamp.org/Enigmatic-benchmark-results-tp4037603p4037619.html

Your remark about copying implies that in fact that openCL isn't worth using for simple computations. That's the same when using threads, one should always check whether the extra overhead outweighs the computation. It should do so for Mandelbrot (few copying indeed) and neural networks (matmult with complex computations). Thanks for the tip about how to copy the data to the device, that makes sense. I'll adjust the examples of the book with that in my mind.

I replaced the c = a * b by c = a * b * a and did not detect any difference. Well, as usual benchmarking requires insight in *alll* the factors lying behind a computation. If you look at the benchmark results you see something funny. In the VectorTri benchmark plain Java performs in about 3 seconds while the openCL code performs in about 300 ms. Exactly the same platform but openCL is 10 times as fast! I forgot to tell that I use Double instead of Float (I need double for most of my computations).