metrics: support multi-k8s in grafana dashboards

[just1900]

Signed-off-by: just1900 [email protected]

What problem does this PR solve?

K8s community and organizations are increasingly deploying multiple Kubernetes clusters to improve availability, isolation and scalability. Since TiDB Operator have support deploying tidb across-kubernetes, this PR will address the multi-k8s issue without affecting existing single-cluster use case.

Issue Number: close #4665

What is changed and how it works?

What's Changed:

• add a k8s_cluster label in all expr
• add k8s_cluster variable in Grafana templating

How it works:

• For users with single-k8s, nothing need to be changed, just use it as before.
• For users with multi-k8s:
  • first add kubernetes label to identify k8s cluster in your prometheus' external_labels.
  • set field "hide" to '0' to show variables in grafana via sed -i s/"hide": 2/"hide": 0/g <path/to/dashboard.json>
  • load it to grafana

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Code changes

• Has exported function/method change
• Has exported variable/fields change
• Has interface methods change
• Has persistent data change

Side effects

• Possible performance regression
• Increased code complexity
• Breaking backward compatibility

Related changes

• Need to cherry-pick to the release branch
• Need to update the documentation
• Need to update key monitor metrics in both TiCDC document and official document

Release note

metrics: support multi-k8s in grafana dashboards

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• overvenus

To complete the pull request process, please ask the reviewers in the list to review by filling /cc @reviewer in the comment.
After your PR has acquired the required number of LGTMs, you can assign this pull request to the committer in the list by filling /assign @committer in the comment to help you merge this pull request.

The full list of commands accepted by this bot can be found here.

Reviewer can indicate their review by submitting an approval review.
Reviewer can cancel approval by submitting a request changes review.

[CLAassistant]

All committers have signed the CLA.

[codecov-commenter]

Codecov Report

Merging #4658 (f7efafd) into master (9607554) will decrease coverage by 0.6668%.
The diff coverage is 39.8884%.

Flag	Coverage Δ
cdc	59.4314% <43.3040%> (-0.4908%)	⬇️
dm	51.2449% <36.2105%> (-0.7840%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

@@               Coverage Diff                @@
##             master      #4658        +/-   ##
================================================
- Coverage   55.6402%   54.9733%   -0.6669%     
================================================
  Files           494        512        +18     
  Lines         61283      63649      +2366     
================================================
+ Hits          34098      34990       +892     
- Misses        23750      25166      +1416     
- Partials       3435       3493        +58     

[overvenus]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 6de8d26

[overvenus]

/run-check-issue-triage-complete

[overvenus]

/merge

[overvenus]

/merge

[overvenus]

/hold

[overvenus]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 821f680

[just1900]

/run-integration-test

[ti-chi-bot]

@just1900: Your PR was out of date, I have automatically updated it for you.

At the same time I will also trigger all tests for you:

/run-all-tests

If the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

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 ti-community-infra/tichi repository.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #4705.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #4706.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #4707.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #4708.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #4709.