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Occasionally, we notice that large amounts of data need to be replicated to maintain the ISR set. This can happen if a broker is offline for hours, perhaps due to machine maintenance or hardware failures, or when a large number of partitions are reassigned.
In these situationsWithout replication quotas, we observe significantly increased end-to-end latency on the cluster, measured by Xinfra Monitor. In the worst cases, tail latency jumps from 10s of milliseconds to multiple seconds.
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