Ardent Performance Computing

Latest Post

PostgreSQL Logical Replicas and Snapshots: Proceed Carefully

Earlier this year, Christos Christoudias – an Engineer from Instacart – published an article on Medium about Creating a Logical Replica from a Snapshot in RDS Postgres. Recently I’ve seen discussions about this article a few times, in a few different places. Is it safe? Is it ok to do this?

A little under a year before publishing this article (just before the pandemic completely shut everything down), Christos presented at the San Francisco Bay Area PostgreSQL Users Group. The YouTube recording is well worth watching. Christos started off his talk by saying “this is a novel not a textbook” which I think is great framing for technical discussions like this. I decided to post a few thoughts here on my own blog as another chapter in that novel.

I’ll start with my colleague’s answer to the question: “Is it ok to do this?” … he said, “Whenever I’ve talked to the author, they said to ‘be careful with that blog’”

I wasn’t in that conversation between my colleague and Christos (I don’t know if Christos really said that) but it perfectly reflects my own sentiment. Be careful with this blog. Let’s dig a little deeper.

First, some background: