Kafka interview questions

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How to Send Large Messages in Kafka ?

Kafka Issue:

Many time while trying to send large messages over Kafka it errors out with an exception – “MessageSizeTooLargeException”. These mostly occurs on the Producer side.

Fixes:

There are couple of configuration properties , you can try making changes and see it that works.

Producer: Increase max.request.size to send the larger message.

Kafka Broker side: replica.fetch.max.bytes – Size used to replicate the messages within the brokers as an practice of Replication.  The Brokers obey this size as a rule to create replicas of a message.  If this size is set as very small, the message is not replicated(fully committed). Hence message will not be committed. And so the consumer will not see the message.

Broker side: message.max.bytes – Maximum size of the message that a Broker can receive from a producer. Try setting this size on a higher side and see if the error exception goes away.

Broker side (per topic): max.message.bytes – Maximum size of the message allowed (by Broker) to be appended to a topic. Defaults is  broker’s message.max.bytes. It can be lower than the broker’s message.max.bytes.

Consumer: Increase max.partition.fetch.bytes to receive larger messages

Kafka Consumer side: fetch.message.max.bytes –  Maximum size of a message that can be consumed by the Kafka consumer.

 

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