PGBouncer
Overview
Section titled “Overview”PGBouncer is a stateless service that acts as a connection pooler for Postgres, with some load balancing built in.
We operate multiple PGBouncer fleets, that handle different portions of the site traffic. As of writing (08/2024), the following fleets exist in production:
- ci
- registry
- sidekiq-ci
- sidekiq
- main
Lead Time
Section titled “Lead Time”Clients connect through a GCP network loadbalancer, and connections are sent to active backend nodes. As such we should be able to remove instances from the pool and perform upgrades without significant disruption, or scheduling lead time.
System Identification
Section titled “System Identification”Knife query:
knife search node 'roles:gprd-base-db-pgbouncer*' -i | sortProcess
Section titled “Process”See Linux Patching Overview for generic processes applied to all Linux systems.
Upgrades will be performed on individual instances or groups of instances at a time, across the multiple pgbouncer fleets that we run:
- Remove the node from the GCP loadbalancer
- Update packages
- Reboot
- Add the node(s) back to the loadbalancer
- repeat.
Additional Automation Tooling
Section titled “Additional Automation Tooling”None currently exists.