Expose config for collecting cgroup and kubelet metrics in kepler exporter API

[vimalk78]

enable/dsiable collecting cgroup and kubelet metrics by exposing bool config params in Exporter API.

Ref: https://github.com/sustainable-computing-io/kepler/pull/876/files
sustainable-computing-io/kepler#901

[vimalk78]

@rootfs @sunya-ch need your input here

[sunya-ch]

Could you clarify more about this issue? Do you mean to expose it via the Kepler command arguments not via the config map?

[vimalk78]

i mean expose it in ExporterSpec

apiVersion: kepler.system.sustainable.computing.io/v1alpha1
kind: Kepler
metadata:
  labels:
    app.kubernetes.io/name: kepler
    app.kubernetes.io/instance: kepler
    app.kubernetes.io/part-of: kepler-operator
  name: kepler
spec:
  exporter:
    port: 9103
    enableCGroupMetrics: true
    enableKubeletMetrics: true

these values will be used to populate the kepler configmap

[sunya-ch]

Thank you. The key of the configmap variables are all listed here: https://github.com/sustainable-computing-io/kepler/blob/02c16c1e223e32b1d1f20f3c7ad8e8959eb2fd87/pkg/config/config.go#L77.

[sthaha]

@vimalk78 How about something like this. This allows us to add additional fields to each of the metric later on. E.g. say in future, cgroup can not only be enabled but also a filter can be applied on the metrics, this would allow for change to be
added without breaking the api. Also grouping under metrics may allow us to add config that applies to all metrics (if any) in
future without breaking api

exporter:
  metrics:  # keep all metrics under MetricSpec
    cgroups:  # feature specific config
        enabled: true
    kubelet:
        enabled: true
    foobar:
       enabled: true
       additional: config

In general, I am wary of boolean flags.

[sunya-ch]

In addition to enabled, we also need a flag for exposed. Sometimes, we enable it for power model estimation but does not want to expose it to prometheus.

Currently, it uses the same config key though...
https://github.com/sustainable-computing-io/kepler/blob/main/pkg/config/config.go#L420