What problem are you facing?

We are facing the issue that with upgrade to node driver version 4.x the connections to our MongoDB increased in an unexpected amount. Your documentation is describing a default value for maxPoolSize of 10 (https://docs.mongodb.com/drivers/node/current/fundamentals/connection/ ). However from a code perspective it looks like the default value is 100 ( https://github.com/mongodb/node-mongodb-native/search?l=TypeScript&q=maxPoolSize ). This would match the behavior we have discovered.

Can you please clarify the current default behavior? Thanks.

What driver and relevant dependency versions are you using?

* 3.6.8 -> default connection pool seems to be 10

* 4.1.1 -> default connection pool seems to be 100