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The documentation says that ReplicationBytes(Out|In)PerSec metrics report "byte out/in (to the other brokers) rate per topic". However, according to the code, it looks like this statement is misleading , and these metrics actually report only per broker metrics. This mismatch between the documentation and actual implementation might cause problems for users who rely on these metrics. For example, as can be seen here Cruise Control relies on these metrics to build a topic workload model. (howeverHowever, it looks like CC authors are aware of the fact that ReplicationBytes(Out|In)PerSec do not report per topic metrics yet).
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