In Chapter 11, Deciding on Useful Extensions, we learned about some useful extensions that are widely adopted and that can give your deployment a real boost. By way of a follow-up, you will now be introduced to PostgreSQL troubleshooting. The idea is to give you a systematic approach to inspecting and fixing your system to improve performance and avoid common pitfalls. Having a systematic approach definitely pays off.
In this chapter, the following topics will be covered:
- Approaching an unknown database
- Inspecting pg_stat_activity
- Checking for slow queries
- Inspecting the log
- Checking for missing indexes
- Checking for memory and I/O
- Understanding noteworthy error scenarios
Keep in mind that many things can go wrong, so it is important to professionally monitor the database. To figure out what is broken, you have to look into the system in a professional...