Deconstructing an Abstraction to Reconstruct an Outage

We all rely on abstractions to build the applications we use day-to-day. It's easy for those abstractions to feel like impenetrable walls, hiding scary low-level parts of the system - especially for a complex piece of software like a database. That needn't be the case!

In this talk, we'll explore the aftermath of a complex outage in a Postgres cluster. We'll retrace the steps we took to reliably reproduce the failure in a local environment and pull out lessons about debugging complex systems along the way. At one point, we'll dive into the depths of how Postgres represents data on disk and realise that even unfamiliar layers of a system don't need to be scary.