Node.js · Middle · Question 7 of 75

Which of these can block the event loop?

1await fetch(url) that takes 3 seconds to answer
2await readFile() of a large file
✓Correct answer: JSON.parse of a 200 MB string

Explanation

Waiting for the network or disk does not block the loop. Large synchronous operations do: big JSON.parse/stringify, sorting huge arrays, complex regex, sync crypto.

Which of these can block the event loop?

Explanation

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