What is the limit on the connection pool with the database?

Question

MySQL

There is an API on NodeJS, but there is no understanding - what number of connections to the database in the pool is normal and for what load, since I encounter it for the first time, 5, 10, 1999?
How much do you bet and for what needs? I'm specifically interested in loaded services.
Any summaries and links will help, thanks in advance.
Didn't find it myself

Answer 1

Comparable to the number of requests in a year with requests per muscle per second.
There are a thousand requests per second, put a thousand