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Kafka Is FunProgress

Consumer Deep Dive

Consumer groups, rebalancing protocols, offset management, and consumer lag mastery.

  1. 1Consumer Groups & Partition AssignmentA consumer group is a set of consumers that jointly consume a topic. Each partition is assigned to exactly one consumer
  2. 2The Rebalance ProtocolWhen group membership changes (consumer joins/leaves/crashes), the Group Coordinator broker triggers a rebalance. In the
  3. 3Offset ManagementConsumer offsets are committed to the __consumer_offsets internal Kafka topic. enable.auto.commit=true commits offsets p
  4. 4Consumer Lag & MonitoringConsumer lag = (partition LEO) - (consumer committed offset). Zero lag means the consumer is caught up. Growing lag mean
  5. 5Cooperative & Static MembershipStatic membership (group.instance.id) lets a consumer rejoin its group with the same partition assignments after a resta

Knowledge check

Q1.What is consumer lag?

Q2.What does auto.offset.reset=earliest do for a new consumer group?

Q3.Why is group.instance.id useful in Kubernetes?