Ryan Marcus, an assistant professor at the University of Pennsylvania set out to analyze PostgreSQL’s database query optimizer performance over the last decade. Running the join order benchmark on versions 8 through 16, he found PostgreSQL’s tail latency improved significantly, with a 15% performance improvement on average for each new major version. Not all improvements are solely due to the query optimizer, but also to enhancements in the execution engine. Marcus’s findings suggest that upgrading from PostgreSQL 8 to 16 can greatly benefit workload tail latency. It’s worth noting that PostgreSQL is constantly evolving, so comparisons with different versions are necessary for accurate performance evaluation.
https://rmarcus.info/blog/2024/04/12/pg-over-time.html