What is the difference between the libuv thread pool and worker threads in Node.js?
The thread pool is internal to libuv and handles specific operations (fs, DNS, crypto) automatically. Worker threads are a Node.js API where your JavaScript code runs on separate threads for CPU-heavy work. The thread pool is for I/O; worker threads are for computation.
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More FAQs in Thread Pool vs Worker Threads in Node.js: What's the Difference?
When your app does many fs, dns.lookup, or crypto.pbkdf2 operations. The 4 default threads can bottleneck. You tune UV_THREADPOOL_SIZE but do not write code for the thread pool; libuv manages it internally.
For heavy computation like image processing, crypto on the JavaScript side, or large data processing that would block the main thread. You explicitly create worker threads and communicate via messages.
Yes. Your app can use both: the thread pool handles fs operations automatically, and you create worker threads for CPU-heavy computation. They are complementary, not either/or.
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