Node single event loop and multi-threading.

[karliky]

Context

Node is single threaded. That is a very simple explanation of how it works. There is a thread pool to manage file handles. Two event loops, the main one and the worker pool. The main loop is divided in several important phases so it would be great to explain them in a simple way and how threading is managed in node/v8.

References

• https://stackoverflow.com/questions/22644328/when-is-the-thread-pool-used
• https://stackoverflow.com/questions/15526546/confusion-about-node-js-internal-asynchronous-i-o-mechanism
• https://www.future-processing.pl/blog/on-problems-with-threads-in-node-js/
• https://nodejs.org/es/docs/guides/dont-block-the-event-loop/

[karliky]

I found this interesting discussion about how promises are implemented nodejs/node#2736