[ddorian43]

There is no 1 article to explain but you can research each part.

1. One Postgresql connection is a forked process and has memory overhead (4MB iirc) + context switching.

2. A connection can only execute 1 concurrent query (no multiplexing).

3. Asyncpg to be fast, uses the features that I mentioned in my parent post. Those can only be used in Session Pooling https://www.pgbouncer.org/features.html.

The whole point of async is to some other work while waiting for a query (ex a different query).

If you have 10 servers with 16 cores, each vcore has 1 python process, each python process doing 10 simultaneous queries. 10 * 16 * 10 = 1600 opened connections.

The best way IMHO: Is to use autocommit connections. This way your transactions execute in 1 RPC. You can keep multiple connections opened with very light CPU and pooling is best.

I've done 20K short lived queries/second from 1 process with only ~20 connections opened in Postgresql (using Pgbouncer statement pooling).