K3OS - kes-server high CPU

I’ve recently setup an Intel NUC8I5BEH with an i5-8259U CPU. I installed k3os on it, basically vanilla (I’ve only installed a bitwarden helm chart, but this problem exists before that’s installed). It’s not the beefiest thing in the world, but I expect it to run this fairly easily, especially at idle.

The problem: looking at CPU usage in top, k3s-server idles at around 6-8% which seems really high. It also means that the fans in the NUC have to ramp up a bit every now and then meaning it’s a lot noisier than I’d expect. CPU usage also very occasionally spikes to ~20% cpu. All of this is spread across all the cores.

  PID USER      PR  NI    VIRT    RES  %CPU  %MEM     TIME+ S COMMAND
 3245 root      20   0 1311436 565748   8.0   3.5 299:32.38 S k3s-server
 4053 root      20   0  140000  27908   0.7   0.2   5:04.00 S local-path-prov
12929 root      20   0  187060  78940   0.7   0.5  19:37.91 S traefik
 4492 root      20   0  746916  42932   0.7   0.3  11:59.90 S coredns
 3379 root      20   0  822576 139560   0.7   0.9  22:29.98 S containerd

Is this actually high or does it seem reasonable? The node running the containers has low usage (1% via kubectl top node). Anything else I can do to see what’s going on? /var/log/* doesn’t have any messages when idling.

This seems reasonable to me. That is only 8% of one CPU core so its not much. The k3s server never idles really, it constantly monitors and updates the cluster state even if you dont run any user workloads on it.

Maybe you can adjust the cooling policy of the NUC in BIOS to make the fan less anoying.