Microk8s CPU spike


I am using a single EC2 m5.large vm to host my microk8s cluster to run my applications. I am using microk8s 1.21/stable. Recently, around Dec 5, I saw the CPU usage of my cluster spike and gradually keep increasing (over 3 days period) and eventually exhaust the entire VM. Is this a known issue to this version of microk8s? For troubleshooting purpose, any system logs I can look at?

One thing to add, I have a cron job to renew microk8s ‘microk8s refresh-certs -e server.crt’ and ‘microk8s refresh-certs -e front-proxy-client.crt’ every hour. We are using self-signed cert, my understanding, renewing that use very less resources. Wondering will this operation cause CPU spike and eventually kill the cluster. Any idea?