I want to monitor the current/target CPU utilization at the deployment/HPA level using Prometheus. GCP Kubernetes monitoring has these metrics available on Stackdriver dashboard but could not find them how they are tracking it.
Following links contains the list of HPA metrics exposed, which does not have the required/target CPU utilization.
https://github.com/kubernetes/kube-state-metrics/blob/1dfe6681e9/docs/horizontalpodautoscaler-metrics.md
I think you can take a look at cAdvisor. Actually, cAdvisor is a part of kubelet service and represents itself as a monitoring agent for performance and resource usage by the containers within particular node. By default, cAdvisor exposes container statistics across Prometheus metrics which are available in /metrics endpoint for each container. I guess you can use container_cpu_load_average_10s metric in order to fetch CPU utilization per each container for relevant Pod/Deployment.