Idle CPU usage of k3s is high and continuously increases over time

This post is a follow up of a previous post where I deployed k3s on Proxmox VMs. https://canthonyscott.com/setting-up-a-k3s-kubernetes-cluster-within-proxmox/

Given that my k3s cluster is run within virtual machines on a single host (in my closet) the cluster is mostly idle. I use it infrequently to test or experiment with things. The only real deployment I run on it is a Cronjob hourly.

However, over time I have regularly noticed its resource usage slowly creeps up and up until this idle cluster is using obnoxiously high levels of CPU.

I have no  idea what’s its actually doing.

This isn’t the worst I have found it behaving, but this shows it happening over the course of about a week.

Here is the slow climb of CPU use on the master node

And we can see the same CPU use climb on the agent node

I have been able to find reports online from others about k3s having high levels of CPU usage when idle, but unfortunately there is never really a resolution to these posts.

This can be resolved, temporarily, by restarting each node, but the cycle then starts again.

Either way, its very interesting and probably not-ideal behavior for a kubernetes solution that is designed to run lightweight on low-end hardware.