For a while I have been running a Wikibase query service update script for WBStack, which is a Java application on a Kubernetes cluster. Part of that journey has included the updater using all available memory, hitting into the kubernetes memory limit and being OOM killed. The title of the post is a little verbose, but I wanted to include all of the keywords that might help people find the answers to the memory issues that I was running into.

Before getting into my weeds, if you want the answers head straight to

UPDATE: This blog post was written with Java 8. Java 10+ now automatically recognizes memory limits and enforces them.

Continue reading