Issues with lots of DB connections
Increasing connections by itself may cause issues downstream, such as increased CPU usage
See https://gitlab.zendesk.com/agent/tickets/528801 for an example
It seems a common theme is the lack of connection pooling (only 1 PgBouncer or none), despite being recommended in the reference architecture (https://docs.gitlab.com/ee/administration/reference_architectures/25k_users.html#configure-pgbouncer)
Edited by Thong Kuah