mongoose poolsize best practice

Question

Forgive me if there's already been an answer to this somewhere, but I haven't seen anything definitive in the docs.

Is there a limit to the size of the connection pool? I have a situation where there could be 100s or 1000s of connections open at once - should the connection pool be used for this or would that be an abuse of the feature?

Answer 1

Is there a limit to the size of the connection pool?

Probably not, however a greater concern is that each connection will take up RAM.

I have a situation where there could be 100s or 1000s of connections open at once - should the connection pool be used for this or would that be an abuse of the feature?

I don't see this being an abuse. I think during the times you have 100 or 1000 clients connecting at once, the server would handle the connections much better.

However if there is only 10 clients connecting and you have a connection pool of 1000, 900 connections could be seen as wasted resources.

Source: Deep Dive into Connection Pooling

I do not have any experience with connection pools, so don't take my information as granted. I would like to hear from someone with experience on the topic.

Answer 2

It turns out that using the connection pool to manage traffic to more than one database isn't possible - which is what I was aiming to do. The solution I'll be using involves creating numerous connections using createConnection(), closing any unused ones.

See an issue I opened in the Mongoose git project for a fuller explanation https://github.com/Automattic/mongoose/issues/6206