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Current state: "Under Discussion"

Discussion thread: here

Vote thread: here

JIRA: here

Please keep the discussion on the mailing list rather than commenting on the wiki (wiki discussions get unwieldy fast).

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Note: A drawback of the approach is that metrics for topics containing periods will be emitted twice: once with the actual topic name and once with periods replaced. Users must monitor either metric and may need to discard duplicate metrics for accurate reporting. But this is necessary to maintain backward compatibility and prevent disruption to existing user reporting.

Example:

Kafka 4.x:

• Topic Name: topic.a.b
  • Deprecated Metric: A metric with the tag topic_a_b will continue to be emitted, but it will be marked as deprecated.
  • New Metric: A new metric with the topic tag topic.a.b and same name has been introduced. Users should transition to this new metric.
• Topic Name: topic_c_d
  • Metric: A metric with the tag topic_c_d will continue to be emitted without any changes.
  • No Additional Metrics: No additional metrics are needed as the existing metric functions correctly.

Kafka 5.0:

The period replacement policy will be completely removed.

Compatibility, Deprecation, and Migration Plan

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