I want to calculate the cpu usage of all pods in a kubernetes cluster. I found two metrics in prometheus may be useful:

container_cpu_usage_seconds_total: Cumulative cpu time consumed per cpu in seconds.
process_cpu_seconds_total: Total user and system CPU time spent in seconds.

Cpu Usage of all pods = increment per second of sum(container_cpu_usage_seconds_total{id="/"})/increment per second of sum(process_cpu_seconds_total)

However, I found every second's increment of container_cpu_usage{id="/"} larger than the increment of sum(process_cpu_seconds_total). So the usage may be larger than 1...