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  • Dien Sanh Luong thinks this is interesting:

Node is single-threaded. This means that every visitor or session is added to that one thread. So it is possible for a two-second database write operation to hold up every other user for two seconds. Multiply this by just 10 users and you've got a big problem on your hands.

From

Cover of Mongoose for Application Development

Note

That is not accurate, according to the following:

<https://www.quora.com/How-does-Node-js-work-asynchronously-without-multithreading>

I/O operations such as database writes are performed in other threads, separate from the event loop thread.