Everything I Thought I Knew about the Event Loop Was Wrong
summary
The event loop is not a separate thread but part of the single JS thread and libuv uses a libuv thread pool of four threads for only certain OS-blocking work; it runs distinct phases (timers, callbacks, I/O poll, setImmediate) not a simple queue. Tick-frequency is misleading; measurable, useful signals are work process latency (thread-pool wait) observed by pounding sharp image processing and event-loop latency (callback delay) measured with setTimeout/setImmediate. A dashboard of those metrics is built and works but requires baselining and correlation to be actionable.
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chapters (7)
- 0:00Start
- 4:09What we know Lo que sabemos
- 5:11Show me a picture! Muestrame una foto!
- 6:57Derived Misconceptions Conceptos erróneos derivados
- 11:55Reality Realidad
- 14:07My Turn... Mi turno
- 28:39What does "latency" mean here? ¿Qué significa "latencia" aqui?
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