PostgreSQL at Scale: Connection Pooling, Partitioning & Read Replicas

Taming Relational Growth

PostgreSQL remains the undisputed workhorse of enterprise applications, yet scaling it to handle millions of transactions requires disciplined operational engineering. When connection overhead begins choking CPU performance, standard connection pooling is insufficient.

Implementing PgBouncer in Transaction Mode

Each active PostgreSQL connection incurs substantial memory overhead. By routing all application traffic through PgBouncer running in transaction pooling mode, we successfully supported 12,000 active application threads against an underlying pool of just 150 database connections, eliminating connection starvation.

Declarative Table Partitioning

For high-write tables exceeding hundreds of gigabytes (such as audit logs and financial ledger entries), declarative range partitioning by month reduced index tree traversal times by 70% and allowed effortless data retention pruning through atomic partition drops.