Hello and welcome. For this video, we're focusing in on understanding a narrow but very critical aspect of performance tuning with PostgreSQL. Specifically, we're going to be discussing Vacuum and Autovacuum. The commands may be short but they have a major impact on your system and understanding them along with what all is going on under the hood will be mission critical. That being said, let’s get started.

Before we dive into vacuum and autovacuum, we need to first grasp some key data principles that Postgres operates on. Let's start with MVCC. Without getting too deep in the computer science, MVCC is a means for solving a concurrency issue within databases. More specifically, there is an old problem about what happens when data must be modified while others are reading or trying to read that same bit of data. One old means would have been to just lock that bit of data down while it is being read or updated to maintain consistency. However, in a modern application,...