OptimizeMe Challenge

Code optimization challenge for PHP developers.

PHP modified adaptation. Based on homework task for Golang educational project with Romanov Vasily “Technosphere Mail.ru Group” at Moscow State University. Lomonosov.

Introduction

Task for working with the xdebug profiler.

There is a Search method that parses the file and displays the necessary data. It doesn't fast enough. It is necessary to optimize the code of this method.

Target

Learn to work with xdebug profiler, find hot spots in the code, be able to build a profile CPU and memory consumption, optimize the code taking this information into account.

Task

Using xdebug profile optimize the search method. The source code of the method is located in the file src/Slow/Search.php, the new implementation should be written in the file src/Fast/Search.php.

You can run the benchmark in the root of the project directory php bench.php

To complete the task, need to optimize each param:

• Count (number of starts in 1s): better then slow * 3
• Memory (peak RAM consumption): better then slow / 3
• Best Time (fastest time for one pass): better then slow / 3

Install

Run composer create-project k-samuel/optimize-me

Benchmark

Run php bench.php

Note: Memory consumption statistics accessible only for PHP >= 8.2

Expected results

Try to get comparable (or better) results. Please note that performance is highly dependent on your hardware and results may vary.

PHP 8.2 + opcache + JIT, apple M2

	Count	Memory	Best Time
Slow	250	2,856.453 kb	0.003882 s.
Fast	1536	516.797 kb	0.000645 s.

Useful materials

• https://www.npopov.com/2014/12/22/PHPs-new-hashtable-implementation.html
• https://github.com/rurban/smhasher
• https://php.watch/articles/jit-in-depth