Node.js Event Loop and Async I/O
Node.js Event Loop and Async I/O
Section titled “Node.js Event Loop and Async I/O”Node.js is designed around asynchronous I/O. Instead of blocking a thread while waiting for network or file operations to finish, Node.js schedules the work and continues handling other events.
Why This Matters
Section titled “Why This Matters”This model lets a single process handle many concurrent connections efficiently when most work is I/O-bound.
What To Understand
Section titled “What To Understand”- the event loop coordinates when queued work runs
- callbacks and promises represent work that completes later
- CPU-heavy work can still block the event loop
Practical Guidance
Section titled “Practical Guidance”Use Node.js when your application does a lot of waiting on databases, APIs, queues, or files. Be careful with CPU-intensive logic inside request handlers.