The "Double buffering + Spiral" in the chart example bothered me. Indeed, it does look like the double buffering was the source of the speedup. Spiral's solutio

The "Double buffering + Spiral" in the chart example bothered me. Indeed, it does look like the double buffering was the source of the speedup. Spiral's solution used a different memory layout to avoid NUMA overhead: https://www.spiral.net/doc/papers/ipdps2018_dtp.pdf https://www.spiral.net/doc/papers/ipdps2018_dtp.pdf If Spiral spotted the problem automatically that's very cool, but that's elimination of a specific bottleneck, and that is possible to do manually too. The article made it sound like a 2x superoptimizer for arbitrary algorithms, but that's likely too good to be true.