PostgreSQL is incredibly powerful but requires proper tuning to perform at scale. Here are the five steps we use with every client.
Step 1: Identify Slow Queries
Enable pg_stat_statements and query the slowest queries:
SELECT query, mean_exec_time, calls FROM pg_stat_statements ORDER BY mean_exec_time DESC LIMIT 20;This immediately shows you where time is being spent.
Step 2: Fix Missing Indexes
Use EXPLAIN ANALYZE to find sequential scans on large tables. Add indexes strategically — partial indexes for filtered queries, composite indexes for multi-column WHERE clauses.
Step 3: Tune postgresql.conf
Key parameters to adjust based on your server RAM: - shared_buffers = 25% of RAM - effective_cache_size = 75% of RAM - work_mem = RAM / max_connections / 4 - max_wal_size = 4GB for write-heavy workloads
Step 4: Optimize Autovacuum
Bloated tables kill performance. Tune autovacuum to run more aggressively on high-write tables: - autovacuum_vacuum_scale_factor = 0.01 - autovacuum_analyze_scale_factor = 0.005
Step 5: Connection Pooling
Use PgBouncer in transaction mode to reduce connection overhead. This alone can improve throughput by 3-5x on high-concurrency workloads.
InfraOpex Database Services
We provide managed PostgreSQL administration including performance tuning, HA setup, and 24/7 monitoring. Contact us for a free database health check.