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 https://developers.redhat.com/blog/2017/04/04/openjdk-and-containers/

UPDATE: This blog post was written with Java 8. Java 10+ now automatically recognizes memory limits and enforces them. https://www.docker.com/blog/improved-docker-container-integration-with-java-10/

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