What is replica.fetch.max.bytes used for?

What is replica.fetch.max.bytes used for?

• A. The maximum size of a message that can be replicated across brokers.
• B. The maximum data returned by broker per partition.
• C. The maximum data returned for each fetch request.
• D. The maximum size of a message that can be received by a producer

Answer: (A)

Replica.fetch.max.bytes defines how much data a broker will pull in one replication fetch from its leader. In Kafka, followers continuously fetch data from leaders to keep replicas in sync, and this setting caps the amount of data returned in a single fetch response. That means it directly controls the size of the replicated data transfer per fetch, which is why it’s described as the maximum size of a message that can be replicated across brokers in one operation. It’s about replication traffic between brokers, not about what producers send or what consumers fetch. Increasing it can improve replication throughput by transferring more data per request, but it also raises memory usage on the follower; decreasing it reduces memory use but may increase the number of fetch rounds.

Replica.fetch.max.bytes defines how much data a broker will pull in one replication fetch from its leader. In Kafka, followers continuously fetch data from leaders to keep replicas in sync, and this setting caps the amount of data returned in a single fetch response. That means it directly controls the size of the replicated data transfer per fetch, which is why it’s described as the maximum size of a message that can be replicated across brokers in one operation. It’s about replication traffic between brokers, not about what producers send or what consumers fetch. Increasing it can improve replication throughput by transferring more data per request, but it also raises memory usage on the follower; decreasing it reduces memory use but may increase the number of fetch rounds.