Hi Steve, thanks for your help. Your comment made me realise that maybe the problem is my pgBouncer configuration, specifically default_pool_size. It took me a while to understand pgbouncer, and I still had some doubts when I configured it. Now I undesrtand better.
I connect to all databases with the same user. However, I had set default_pool_size=10. So with more than 150 databases, it was very probable that postgresql reach max_connections=250 limit. I didn't have set reserve_pool_timeout or max_db_connections, but docs say their default values are reserve_pool_timeout=5 seconds, max_db_connections=unlimited. I've reviewed pgBouncer configuration and did some search. I've found this thread where the first person that responds gives a great explanation abount how pgbouncer do its maths: https://github.com/pgbouncer/pgbouncer/issues/174 So, what I did for now was to set this in pgbouncer configuration: default_pool_size=1 min_pool_size = 0 server_idle_timeout = 30 reserve_pool_size = 10 reserve_pool_timeout = 5 max_db_connections = 5 I'll keep monitoring with this setup, but I can already tell you that the total number of connections in postgres has significantly reduced (from ~100 to ~60). So I guess the problem was a bad setup of pgbouncer. Thank you all for your help! -- View this message in context: http://www.postgresql-archive.org/GMT-FATAL-remaining-connection-slots-are-reserved-for-non-replication-superuser-connections-but-I-m-g-tp5946245p5946827.html Sent from the PostgreSQL - general mailing list archive at Nabble.com. -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
