Is kubectl top the current memory / CPU value?

Question

Is kubectl top the current memory / CPU value or is it an average of a certain time period ?

Answer 1

It's the actual usage of the pods and nodes at the moment you issue the command.

Example:

$ kubectl top nodes
NAME                                         CPU(cores)   CPU%   MEMORY(bytes)   MEMORY%
ip-xxx-xx-x-xxx.us-west-2.compute.internal   62m          6%     1014Mi          27%

Using 62 milicores(0.062 cores), 6% of the CPUs, 1014 Mebybites and 24% of the memory at the moment the API returned.

You can also find more information here.

Answer 2

"kubectl top node" doesn't provide the real-time of nodes's CPU usage. It will have around 5-20 seconds delay. You could check the output of <date; kubectl top nodes; kubectl get --raw "/apis/metrics.k8s.io/v1beta1/nodes"|jq>.

According to the output, you will find those statastics collected from the interval [Timestamp-Window, Timestamp].