Migrating and Modernizing Oracle Databases to PostgreSQL on AWS – Part 4: Post-cutover optimization

This article covers post-cutover optimization for Oracle-to-PostgreSQL migrations on AWS, transforming functional systems into operationally excellent ones through systematic tuning and observability.

• Establish comprehensive observability using CloudWatch, Database Insights, and pg_stat_statements to detect issues before user impact
• Implement PostgreSQL-specific tuning: autovacuum management, WAL/checkpoint optimization, work_mem configuration, and query statistics
• Validate disaster recovery capabilities through monthly drills measuring actual RTO and RPO against business requirements
• Execute methodical Oracle decommissioning over 16 weeks, maintaining reversibility while realizing cost savings
• Build operational excellence foundation using Infrastructure as Code templates and team training programs for sustained performance
• Deploy hybrid architecture matching workload characteristics: Aurora for high-concurrency, RDS for predictable I/O, Serverless v2 for variable traffic

Successful modernization requires continuous improvement cycles combining monitoring, analysis, optimization, and validation to sustain long-term PostgreSQL operational excellence.