Backend & systems·Concurrency and coordination
one thread sits in a loop pulling ready events off a queue and running the callback for each one.
Event loop
Also calledreactor pattern, single-threaded event loop
The execution model behind Node.js, nginx and most async runtimes: a single thread dispatching completed I/O events to handlers. It removes locking within the loop, since only one handler runs at a time. It makes any long synchronous computation a full-service outage for the duration, which is why CPU work gets pushed to a worker pool.