MDN never disappoints and I find this part of their async/await guide the most interesting:
Async/await makes your code look synchronous, and in a way it makes it behave more synchronously… This means that your code could be slowed down by a significant number of awaited promises happening straight after one another.
Here’s a slightly modified example taken from the article. Each test creates and resolves 3 promises. The slow version will resolve each promise in sequence while the fast version allows each promise to run simultaneously.
https://jsfiddle.net/newtnik/bt6oqjeL/18/
https://jsfiddle.net/newtnik/bt6oqjeL/18/