node.js - Does nodejs create background task or child process to execute callback function -


does nodejs create background task or child process execute callback functions? how nodejs execute query below?

mymodel.find({}, function (err, docs) {   //do thing });

nodejs implements non-blocking i/o achieve these callbacks in single thread. uses event-loop.

on demand of data, nodejs registers callback , send operation event loop. , when data available, callback called.

say thread executing callback a. keep executing, , finds async task. registers new callback b async task. meanwhile waiting data of b, start executing other callback c. once c completed. check if data of b available. if so, executes b. otherwise executes other callback d... , on..

read deep understanding http://blog.mixu.net/2011/02/01/understanding-the-node-js-event-loop/


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