pgbouncer is not a load balancer, it's a connection pooler. The former is used to split reads and writes (and so far I haven't seen "magic" tools that automate

pgbouncer is not a load balancer, it's a connection pooler. The former is used to split reads and writes (and so far I haven't seen "magic" tools that automate it well, pgpool has lots of issues; this task is better to solve in app code -- most modern frameworks either already solved it such as RoR, or at least work well with 2 connections), the latter is used to multiplex connections and improve performance similarly to nginx, haproxy, envoy, but with native Postgres protocol support.