Course 2

Understanding Slowness

Slow Web Server

ab - Apache benchmark tool

ab -n 500 site.example.com

Profiling - Improving the code

Profiling 可透過監控和分析即時資源使用情況，協助軟體工程師設計高效率且有效的應用程式。對 IT 專業人員而言，Profile 的能力是非常寶貴的工具。雖然 Profiling 並非新技術，但類似技術在今日仍然適用，而且 Profiling 可改善反應速度並最佳化資源使用，為軟體開發奠定穩固的基礎

A profiler is a tool that measures the resources that our code is using, giving us a better understanding of what's going on.

• gprof : For C program
• cProfile : For Python program
• pprofile3 + kcachegrind(GUI) : For Python program
• Flat, Call-graph, and Input-sensitive are integral to debugging
• timeit (python module) : Measure execution time of small code snippets

Parallelizing operations

Python modules

• threading
• AsyncIO