Monitoring Pipeline Metrics HPA API

[DirectXMan12]

Description

The new monitoring vision (https://docs.google.com/document/d/1z7R44MUz_5gRLwsVH0S9rOy8W5naM9XE5NrbeGIqO2k/) proposes several APIs for the HPA to access metrics. The master metrics API, used to access "core" resource metrics, is already implemented, but still needs to be stabilized. The vision also proposes an adapter API that allows the HPA to access arbitrary metrics from the monitoring pipeline.

This feature tracks defining the API(s), producing an initial implementation (most likely on top of Heapster), and making sure that the HPA is set up to consume the API.

Sponsored by SIG Instrumentation (@kubernetes/sig-instrumentation) and SIG Autoscaling (@kubernetes/autoscaling)

Progress Tracker

• Alpha
  • Write and maintain draft quality doc
    • During development keep a doc up-to-date about the desired experience of the feature and how someone can try the feature in its current state. Think of it as the README of your new feature and a skeleton for the docs to be written before the Kubernetes release. Paste link to Google Doc: https://docs.google.com/document/d/1z7R44MUz_5gRLwsVH0S9rOy8W5naM9XE5NrbeGIqO2k/
  • Design Approval
    • Design Proposal: Proposal: Introduce Custom Metrics API kubernetes#34586 (in progress)
    • Repository: Kubernetes core or Heapster
    • Initial API review (may be same PR as design doc): PR-NUMBER
      • Any code that changes an API (/pkg/apis/...)
      • cc @kubernetes/api
    • My Shepherd is: @DirectXMan12
    • My Secondary Contact Point is: @derekwaynecarr
  • Write (code + tests + docs) then get them merged. Introduce types and clients for Metrics APIs metrics#2
    • Code needs to be disabled by default. Verified by code OWNERS
    • Minimal testing
    • Minimal docs: Update HPA documentation to cover HPA v2 website#2720
      • cc @kubernetes/docs on docs PR
      • cc @kubernetes/feature-reviewers on this issue to get approval before checking this off
      • New apis: Glossary Section Item in the docs repo: kubernetes/kubernetes.github.io
    • Update release notes
• Beta
  • Testing is sufficient for beta
  • User docs with tutorials
    • Updated walkthrough / tutorial in the docs repo: kubernetes/kubernetes.github.io
    • cc @kubernetes/docs on docs PR
    • cc @kubernetes/feature-reviewers on this issue to get approval before checking this off
  • Thorough API review
    • cc @kubernetes/api
• Stable
  • docs/proposals/foo.md moved to docs/design/foo.md
    • cc @kubernetes/feature-reviewers on this issue to get approval before checking this off
  • Soak, load testing
  • detailed user docs and examples
    • cc @kubernetes/docs
    • cc @kubernetes/feature-reviewers on this issue to get approval before checking this off

FEATURE_STATUS: IN_DEVELOPMENT

More advice:

Design

• Once you get LGTM from a @kubernetes/feature-reviewers member, you can check this checkbox, and the reviewer will apply the "design-complete" label.

Coding

• Use as many PRs as you need. Write tests in the same or different PRs, as is convenient for you.
• As each PR is merged, add a comment to this issue referencing the PRs. Code goes in the http://github.com/kubernetes/kubernetes repository,
  and sometimes http://github.com/kubernetes/contrib, or other repos.
• When you are done with the code, apply the "code-complete" label.
• When the feature has user docs, please add a comment mentioning @kubernetes/feature-reviewers and they will
  check that the code matches the proposed feature and design, and that everything is done, and that there is adequate
  testing. They won't do detailed code review: that already happened when your PRs were reviewed.
  When that is done, you can check this box and the reviewer will apply the "code-complete" label.

Docs

• Write user docs and get them merged in.
• User docs go into http://github.com/kubernetes/kubernetes.github.io.
• When the feature has user docs, please add a comment mentioning @kubernetes/docs.
• When you get LGTM, you can check this checkbox, and the reviewer will apply the "docs-complete" label.

[DirectXMan12]

cc @piosz @fgrzadkowski @derekwaynecarr @kubernetes/autoscaling @kubernetes/sig-instrumentation

[idvoretskyi]

@DirectXMan12 any updates on this issue? Can you provide the actual status of it and update the checkboxes above?

[DirectXMan12]

The proposal is posted, but has not been approved yet. We only recently reached general consensus about the design. Still finalizing the exact semantics. It should be removed from the 1.5 milestone, since no code will have gone into 1.5

[idvoretskyi]

@DirectXMan12 thank you for clarifying.

[apsinha]

@DirectXMan12 there maybe users who are currently using the previous alpha implementation of custom metrics. Can we prepare user documentation for such users ahead of the release? We would like to be careful not to break pod auto-scaling for any users.

[idvoretskyi]

@DirectXMan12 please, provide us with the release notes and documentation PR (or links) at https://docs.google.com/spreadsheets/d/1nspIeRVNjAQHRslHQD1-6gPv99OcYZLMezrBe3Pfhhg/edit#gid=0

[DirectXMan12]

@DirectXMan12 please, provide us with the release notes and documentation PR (or links)

done :-)

[DirectXMan12]

@idvoretskyi this is beta in 1.8

[apsinha]

@DirectXMan12 did we move to beta with any changes? I could not find any documentation of any changes, just wanted to confirm...

[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.

Prevent issues from auto-closing with an /lifecycle frozen comment.

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

[DirectXMan12]

/remove-lifecycle stale

[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

[justaugustus]

@DirectXMan12
Any plans for this in 1.11?

If so, can you please ensure the feature is up-to-date with the appropriate:

• Description
• Milestone
• Assignee(s)
• Labels:
  • stage/{alpha,beta,stable}
  • sig/*
  • kind/feature

cc @idvoretskyi

[DirectXMan12]

I'm going to close this feature issue, and we'll roll it into the HPA one. The features are so tightly entwined that it makes sense to track together.

[justaugustus]

Thanks for consolidating, Solly!