Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Ingester: Add matchers to LabelNames() ingester RPC #6209

Open
wants to merge 1 commit into
base: master
Choose a base branch
from

Conversation

harry671003
Copy link
Contributor

@harry671003 harry671003 commented Sep 12, 2024

What this PR does:
Prometheus has supported matchers in LabelNames() API also. This change will pass the matchers to LabelNames() call on ingesters.

The main motivation is to improve the efficiency of /api/v1/labels and avoid using the MetricsWithLabelMatchers() call when it's not necessary.

Which issue(s) this PR fixes:
Fixes #

Checklist

  • Tests updated
  • Documentation added
  • CHANGELOG.md updated - the order of entries should be [CHANGE], [FEATURE], [ENHANCEMENT], [BUGFIX]

@harry671003 harry671003 changed the title Add matchers to LabelNames() ingester RPC Ingester: Add matchers to LabelNames() ingester RPC Sep 12, 2024
@harry671003 harry671003 changed the title Ingester: Add matchers to LabelNames() ingester RPC Ingester: Add matchers to LabelNames*() ingester RPC Sep 12, 2024
@harry671003 harry671003 marked this pull request as ready for review September 12, 2024 19:20
@harry671003 harry671003 changed the title Ingester: Add matchers to LabelNames*() ingester RPC Ingester: Add matchers to LabelNames() ingester RPC Sep 12, 2024
@@ -109,6 +109,10 @@ querier:
# CLI flag: -querier.ingester-metadata-streaming
[ingester_metadata_streaming: <boolean> | default = true]

# Use LabelNames ingester RPCs with match params.
# CLI flag: -querier.ingester-label-names-with-matchers
[ingester_label_names_with_matchers: <boolean> | default = false]
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Do we need this config?
If the matcher is in the request, its not cause we always wanna filter out?

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

This feature flag is for safe guarding during a deployment.
In this PR, queriers will start calling ingester LabelNames with Matchers. But if ingesters haven't restarted yet, then ingesters will ignore that and return label names without filtering out.

We can remove this flag in 2 releases and make this behavior the default.

Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I suggest we add TODO or create an issue about removing/deprecating this flag now. Otherwise we will forget

Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I was thinking that if the ingesters ignored the matchers in the request from the querier since the ingesters had not restarted yet, wouldn't that be the same behavior today since the ingesters already do not handle the matchers?

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Today's behavior for label names calls with matchers is like this:

  • Querier will retrieve all the series using MetricsForLabelMatchers call. It'll then get the unique label names from the retrieved series.

The new behaviour is for label names calls with matchers:

  • Querier will directly call LabelNames call and pass the matchers.
  • If ingesters ignore the matchers, this will break the API.

I think having the feature flag is unavoidable.

Created #6222 for tracking the deprecation of the flag.

Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I see, thank you for the clarification @harry671003.

Signed-off-by: 🌲 Harry 🌊 John 🏔 <[email protected]>
Copy link
Contributor

@yeya24 yeya24 left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Thanks!

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
Projects
None yet
Development

Successfully merging this pull request may close these issues.

4 participants