Improve documentation of kubectl top

[serathius]

Due naming purpose of kubectl top is misinterpreted and compared to similarly named linux system tools. We should ensure that users understand meaning of those values and have proper expectation for this tool. Discussion: kubernetes-sigs/metrics-server#447

I propose to improve command help that would do better explanation and link to relevant documentation in Kubernetes docs.

We should explain or link to documentation explaining:

• Where metrics come from
• How they are calculated
• How percentages are calculated
• How they relate to HPA
• When they should be used and why they shouldn't replace traditional tools and monitoring solutions

/sig instrumentation
/area kubectl
/kind feature

[k8s-ci-robot]

@serathius: The label(s) sig/, area/ cannot be applied, because the repository doesn't have them

In response to this:

Due naming purpose of kubectl top is misinterpreted and compared to similarly named linux system tools. We should ensure that users understand meaning of those values and have proper expectation for this tool. Discussion: kubernetes-sigs/metrics-server#447

I propose to improve command help that would do better explanation and link to relevant documentation in Kubernetes docs.

We should explain or link to documentation explaining:

• Where metrics come from
• How they are calculated
• How percentages are calculated
• How they relate to HPA
• When they should be used and why they shouldn't replace traditional tools and monitoring solutions

/sig instrumentation
/area kubectl
/kind feature

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[fejta-bot]

Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.
Stale issues rot after an additional 30d of inactivity and eventually close.

If this issue is safe to close now please do so with /close.

Send feedback to sig-testing, kubernetes/test-infra and/or fejta.
/lifecycle stale

[serathius]

/help

[k8s-ci-robot]

@serathius:
This request has been marked as needing help from a contributor.

Please ensure the request meets the requirements listed here.

If this request no longer meets these requirements, the label can be removed
by commenting with the /remove-help command.

In response to this:

/help

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[serathius]

/remove-lifecycle stale

[eddiezane]

/priority backlog

[fejta-bot]

Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.
Stale issues rot after an additional 30d of inactivity and eventually close.

If this issue is safe to close now please do so with /close.

Send feedback to sig-testing, kubernetes/test-infra and/or fejta.
/lifecycle stale