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Compatibility, Deprecation, and Migration Plan

TBD

What impact (if any) will there be on existing users?

Clients

Short of the configuration property to disable telemetry (enable.telemetry=false - enabled by default) there are no user-facing changes to client users.

Depending on metrics subscription intervals there might be increased CPU and network load, but for modestly set subscription intervals this should be negligible.

Broker

The Kafka admin needs to explicitly configure a Metrics reporter plugin that supports the new push-based telemtry interface. If no such plugin is configured the telemetry collection is disabled and there will be no user-facing changes.

Depending on the metrics subscription patterns and intervals there is likely to be increased CPU and network load as brokers will receive, decompress and forward pushed client telemetry to the metrics plugin.

If we are changing behavior how will we phase out the older behavior?

No behavioural changes.

If we need special migration tools, describe them here.

None.

When will we remove the existing behavior?

Not relevant.

Rejected Alternatives

Dedicated Metrics coordinator based on client instance id

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