PostgreSQL Performance

Connection Pooling

Learn why PostgreSQL connection pooling is essential for high concurrency and how it reduces overhead in production systems.

Definition

A technique to maintain a cache of database connections that can be reused across multiple requests.

Opening and closing PostgreSQL connections frequently is expensive. Pooling keeps backend usage stable and reduces latency spikes.

It is a core control for high-concurrency API and microservice workloads.

Pool sizing, timeout policy, and transaction mode affect real results more than tool choice alone. Validate with workload testing.

What is PostgreSQL connection pooling?

Connection pooling reuses a controlled set of database connections instead of opening a new connection for every request.

Why is pooling important at scale?

It reduces connection overhead, stabilizes backend utilization, and improves latency consistency under burst traffic.

Can pooling fix all performance problems?

No. It helps connection management, but query plans, indexes, and storage performance still drive core throughput.

How should teams size pools?

Start from workload concurrency, DB limits, and transaction characteristics, then tune with measured load tests.

What is a common pooling mistake?

Overprovisioning pool size without testing can increase contention and degrade performance rather than improve it.