Understanding query performance patterns are essentially the foundation for query performance tuning. It, in many ways, dictates how a database cluster evolves. And then there are obviously direct and indirect cost connotations as well.
With improved observability, using the right tools, you can get the best out of your existing setup and ensure that it is able to handle not only the average load profile but peak load as well. We'll see how different tools like pg_stat_activity, pg_stat_statements, auto_explain, pgBadger, and pg_stat_monitor can deliver a complete picture to help measure, analyze and optimize your queries and database system.