I like it how he demonstrates the thought process. It seems quite a mechanical recipe that can be applied to a lot of similar problems: Step 1:. A slow but ea

I like it how he demonstrates the thought process. It seems quite a mechanical recipe that can be applied to a lot of similar problems: Step 1:. A slow but easy implementation. It allows to make sure the algorithm is correct, and later allows validating the faster variants. Step 2: Algorithm and datastructure optimization, guided by profiling. Step 3: Micro optimization, again guided by profiling. A standard bag of tricks is applied. I didn't see cache friendlyness/tiling in here, which surprised me. Step 4: Parallelism, first by SIMD then by threads. I am very much not downing the author: This is a great teaching of the process, it's a lot of hard brainy work, and we didn't see everything he tried but which failed. So thank you, author. My point is: it is not magic. It is engineering. It is a skill that can be aquired, thought, even planned and measured.