Back to Transmission Log
Databases

Database Tuning: Scaling PostgreSQL to 10M+ Daily Rows

Learn how we refactored query plans, optimized index structures, and tuned cache allocations to save database CPU.

Tamim
Lead Architect
March 02, 2026 9 min read
Database Tuning: Scaling PostgreSQL to 10M+ Daily Rows

As data grows, query speeds decrease exponentially. Learn the index optimizations and engine parameter tuning we applied to keep our PostgreSQL instances performing under heavy transaction loads.

1. Leverage Explain Analyze to Diagnose Bottlenecks

Never create indices blindly. Always inspect query plans using EXPLAIN ANALYZE. Identify if the engine is doing sequential table scans (slow) or index scans (fast).

2. Partial and Covering Indices

If you only query rows that have an active state, create a Partial Index. This keeps index file sizes small and cached in memory:

CREATE INDEX idx_active_users ON users(email) WHERE status = 'active';

3. Connection Pooling with PgBouncer

PostgreSQL spins up a new backend process for every client connection, which consumes memory quickly. We deploy PgBouncer to manage a pool of reusable connections, reducing database overhead and increasing transaction throughput by 4x.

Subscribe to Transmission Uplink

Join 5,000+ engineers receiving our monthly architectural digests, framework updates, and DevOps blueprints.