Postgres lowering max_connection I have a question regarding max_connections in postgresql.conf. 

In the Postgresql documentation, it says it determines the maximum number of concurrent connections to the database server. Does it literally mean users connected to it? or am I missing something?
It is the number of connections.  It is not the number of users, as one user can have many connections concurrently and each one counts against max_connections.  And you can also have many more users than connections, as long as users are not permanently connected.