If you’re hosting your databases within a Virtual Machine (VM) or on some big iron, one of the principal bottlenecks you’re likely to see within your PostgreSQL clusters is I/O. With I/O at the center of potential performance problems, a good understanding of how PostgreSQL manages it is very important. I’m going to start with just how things are stored on disk. We’ll get to how writes and reads occur in another article.
Before we get into the details, I do want to address a couple of issues around data storage and PostgreSQL. First up, extensions. Some of the most