Backend from first principles - 22. Concurrency & Parallelism: IO Bound vs CPU Bound

A comprehensive guide to concurrency and parallelism for backend engineers. We cover: - Why Concurrency Matters for Backend Systems - IO Bound vs CPU Bound Operations - Concurrency vs Parallelism - Threading Model - Event Loop Model (Async/Await) - Virtual Threads (Goroutines) - Race Conditions & Solutions Timestamps: 0:00 Introduction: Why Concurrency Matters 2:51 The Cost of Not Using Concurrency 5:55 IO Bound vs CPU Bound Operations 9:44 Concurrency vs Parallelism Explained 15:16 Visualizing Concurrent Request Handling 19:14 Threading Model Deep Dive 23:22 Thread Overhead & Context Switching 37:15 Event Loop Model Deep Dive 43:03 Async/Await Explained 50:28 Virtual Threads & Goroutines (Go Runtime) 1:03:46 How Async/Await Works Under the Hood (State Machines) 1:15:32 Race Conditions & Shared State Problems 1:23:28 Solutions: Locks, Mutexes & Channels 1:26:02 Summary & Key Takeaways Join the Discord community: https://discord.gg/NXuybNcvVH #backend #nodejs #golang #softwareengineering Nerd out about the history of technologies here https://www.fascinatingtechhistory.xyz/