PostgreSQL Best Practices: Performance, Backup & Scaling

6 min read

PostgreSQL is powerful, flexible, and—if you misconfigure it—subtly unforgiving. Whether you’re running a single-app database or managing a fleet of replicas, following clear PostgreSQL best practices saves time (and panic) later. In my experience, most performance and reliability issues come from a few avoidable mistakes: bad indexes, neglected maintenance, and reckless configuration changes. This article walks through practical, beginner-friendly, and intermediate-level best practices for performance tuning, indexing, backup and restore, replication, and day-to-day maintenance.

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Start with the right mindset

You don’t need to be an expert to get reliable results. Focus on three things first: correct data modeling, realistic workload testing, and observability. Sound boring? Maybe. Effective? Absolutely.

Data modeling: conventions that matter

Keep schemas logical. Use meaningful names. Avoid serializing complex data into single text blobs unless you have a clear reason. From what I’ve seen, well-modeled data reduces the need for expensive workarounds later.

Test with real-ish data

Benchmarks are only useful if the data distribution and query mix resemble production. Try a staging dataset that mirrors row counts, cardinality, and index selectivity.

Performance tuning essentials

Performance in PostgreSQL is mostly about configuration, indexes, and queries. A few knobs provide the biggest wins.

Configuration pointers

  • shared_buffers: Set to ~25% of available RAM for dedicated DB servers.
  • work_mem: Tune per-session memory for sorts and hashes; too high and you risk OOM.
  • maintenance_work_mem: Increase during bulk loads or index builds.
  • effective_cache_size: Hint for planner; set to the OS cache size plus shared_buffers.
  • max_connections: Prefer a connection pooler (pgBouncer) over huge connection counts.

These are starting points; always measure. See the official docs for details on each parameter: PostgreSQL Documentation.

Use observability: pg_stat_statements and more

Install pg_stat_statements. I can’t stress this enough. It shows the slowest queries by total time. Combine with system metrics (CPU, I/O, memory) and you’ll find low-hanging fruit fast.

Indexing strategies

Indexes speed reads and slow writes. Think carefully. Here are practical rules I use every day.

  • Index columns used in WHERE, JOIN, ORDER BY, and GROUP BY.
  • Prefer single-purpose indexes; multi-column indexes should match query predicates order.
  • Avoid indexing low-selectivity boolean or near-constant columns.
  • Use partial indexes for sparse conditions: they’re tiny and fast.

Common index types and when to use them

Type Best for Notes
B-tree Equality and range queries Default; most queries
GIN Full-text and array containment Great for jsonb & text search
GiST Geospatial and custom types Used by PostGIS

Vacuuming, autovacuum, and bloat

PostgreSQL uses MVCC. That means dead rows accumulate and must be reclaimed. Autovacuum helps, but you need to tune it.

  • Monitor table bloat with pg_stat_user_tables and autovacuum logs.
  • Raise autovacuum frequency for high-churn tables.
  • Use VACUUM FULL rarely—prefer pg_repack if you need online compaction.

Backups and restore strategies

Backups are insurance. Test restores. Don’t assume backups work because they ran. I once watched a failed restore at 2am—unpleasant and avoidable.

Practical backup plan

  • Use base backups + WAL archiving for point-in-time recovery (PITR).
  • Automate regular logical dumps (pg_dump) for schema-level snapshots.
  • Encrypt backups in transit and at rest.
  • Document and test a restore playbook quarterly.

For an authoritative guide on backup and PITR, reference the official docs: Continuous Archiving and Point-in-Time Recovery.

Replication & high availability

Replication is straightforward but your HA story depends on failover automation and monitoring.

Options

  • Streaming replication for near-real-time replication.
  • Logical replication for selective replication between major versions.
  • Use a cluster manager (Patroni, repmgr) for automated failover; avoid manual switchover in big setups.

Security basics

Security is more than roles and passwords. Protect the data plane and the control plane.

  • Use SSL/TLS for client connections.
  • Follow least-privilege for roles and extensions.
  • Keep Postgres patched and monitor CVEs.

Operational tips: automation and testing

Automate routine tasks: backups, failover tests, schema migrations, and monitoring alerts. Use migrations with version control (pg-migrate, Flyway, Liquibase).

Schema changes without downtime

Use online-friendly migrations: CREATE INDEX CONCURRENTLY, ADD COLUMN with defaults as nullable plus a backfill step, and avoid long locks in peak hours.

Common pitfalls and how to avoid them

  • Over-indexing: slows writes and wastes space. Keep indexes purposeful.
  • Ignoring autovacuum: bloat and slow queries follow.
  • Too many connections: use a pooler to avoid memory pressure.
  • Relying only on logical backups: they don’t replace PITR for corruption scenarios.

Real-world checklist (quick wins)

  • Enable pg_stat_statements and review top 10 slow queries weekly.
  • Set up WAL archiving and test PITR.
  • Deploy a connection pooler like pgBouncer for web apps.
  • Monitor autovacuum activity and tune thresholds for hot tables.
  • Document your recovery runbook and test it.

If you want to go deeper, the PostgreSQL project documentation is the canonical source and very practical: PostgreSQL Documentation. For a quick historical overview, see PostgreSQL on Wikipedia. If you’re running Postgres on AWS, their guidance for RDS Postgres contains useful operational notes: Amazon RDS for PostgreSQL.

Final thoughts

Good Postgres operations are iterative: measure, change one thing, measure again. Start small—reasonable configuration, sensible indexes, backups you’ve tested—and build up. What I’ve noticed: teams that prioritize observability and repeatable playbooks sleep better. And isn’t that worth a few config tweaks?

Frequently Asked Questions

Start with shared_buffers, work_mem, maintenance_work_mem, effective_cache_size, and max_connections. Tune them based on available memory and workload, and measure before/after changes.

Autovacuum should handle most workloads; increase its frequency for high-churn tables. Monitor table bloat and run manual VACUUM or pg_repack only when necessary.

Use base backups plus WAL archiving for point-in-time recovery (PITR), supplement with regular logical dumps (pg_dump), encrypt backups, and regularly test restores.

Use streaming replication for near-real-time physical replication; use logical replication when you need selective replication, cross-version replication, or row-level filtering.

Use a connection pooler like pgBouncer to limit database connections and reduce per-connection memory overhead. Also tune max_connections to realistic values.