The best work includes benchmarks comparing a naive algorithm vs. an optimized PHP 7 version using OPcache and JIT (in PHP 8, but planned since PHP 7).

by Mizanur Rahman. While the full copyrighted PDF is not legally available for free download, you can access substantial components of it and the accompanying code through official channels. Google Books Core Resource Details Full Title

: Master recursive algorithms and optimize them using memoization. Where to Find Support Files and Downloads