How to debug high CPU AWS RDS Postgres?

Question

Hello I'm looking at Performance Insights in AWS RDS (Postgres 10)

I slice by "Waits"

When I see Top databases, Top Applications, Top session Types and Top Users they are all actually higher than the SQL queries it self

From these metrics how do you tell what is bottlenecking the CPU?

Answer 1

Top waits, Top SQL, etc. are all different dimensions that you can use to understand what's contributing to database load. Dimensions are not comparable with each other.

It sounds like you want to diagnose what's contributing to the PostgreSQL "CPU" wait event. You can find more information on this topic in the official RDS docs on Tuning with wait event.

If the issue turns out to be suboptimal queries, then you can find the worst performers in the Top SQL tab (dimension) of Performance Insights.