Many of modern programming languages use lightweight threads (virtual threads/coroutines/goroutines) and thus scalability does not limited by number of threads anymore.
But if these lightweight threads interact with PostgreSQL and start transactions than the limit is a connection pool. Is there a way to run tens of thousands transactions? Maybe by using a single given connection for several concurrent transactions, started by lightweight threads? Maybe it can be achieved with r2dbc?
Is there any other DMBS that allow such a behaviour (if is not possible with PostgreSQL)?