Multi Step Processes medium
You have a Kafka topic with 10 partitions. You spin up 20 consumer instances in the same Consumer Group. What happens?
- A Processing speed doubles.
- B Kafka throws an error.
- C 10 consumers will work, and 10 will sit idle.
- D Each partition is processed by 2 consumers.
Answer: C. 10 consumers will work, and 10 will sit idle.
In Kafka, a partition can be consumed by only *one* consumer within a group (to guarantee order). If you have more consumers than partitions, the extras are idle backups.
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