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Diagnosing PgBouncer's max_client_conn limit

PgBouncerrevision 1

Diagnostic tree

  1. In progressPgBouncer is refusing new client connectionsThis is PgBouncer's own `max_client_conn` — the number of frontend (application-side) connections it will accept — not Postgres's `max_connections`, and not PgBouncer's server-side pool size (`default_pool_size` / `max_db_connections`). Those are three independent limits.
View the whole map (7 more steps)
  • Check current clients against the configured limit
  • Break the client count down by pool
  • Not actually at max_client_conn
  • Client connections are consistently at the ceiling
  • Raise max_client_conn and reload without dropping connections
  • Confirm the new limit took effect and there's headroom
  • Resolved

What to test

PgBouncer is refusing new client connections

This is PgBouncer's own `max_client_conn` — the number of frontend (application-side) connections it will accept — not Postgres's `max_connections`, and not PgBouncer's server-side pool size (`default_pool_size` / `max_db_connections`). Those are three independent limits.

What happened?

Passed