New high availability architecture for Aiven for PostgreSQL in limited availability

Aiven has introduced a new high availability architecture for its PostgreSQL service, transitioning from its custom tools, pglookout and pghoard, to the open-source projects Patroni and pgBackRest, now available in limited availability. Patroni enhances cluster management by using a Distributed Consensus Store to prevent split-brain scenarios, dynamically managing configurations, and ensuring seamless failovers. Meanwhile, pgBackRest improves backup performance with parallel processing, allowing for faster completion times and supporting incremental backups, which can significantly enhance backup efficiency for large databases. This new architecture also streamlines PostgreSQL version upgrades with a rolling upgrade approach, minimizing downtime to just a few seconds and enabling users to access new features without disrupting applications. Overall, this upgrade promises increased reliability, enhanced backup performance, and faster maintenance, making Aiven's PostgreSQL databases more resilient and efficient.