Hi, I am looking at the code of kafka.consumer.ZookeeperConsumerConnector.scala (link here <https://github.com/apache/kafka/blob/0.8.2/core/src/main/scala/kafka/consumer/ZookeeperConsumerConnector.scala>) and I see that all ids registered to a particular group ids are registered to the path /consumers/[group_id]/ids in zookeeper. the ids contain the consumer_id -> topics mapping.
A watcher is registered in zookeeper that is triggered when there is a change to /consumers/[group_id]/ids. This watcher event is handled by the class ZKRebalancerListener. This class calls a synced rebalance whenever a watcher event is received. So here is my question. 1. Lets consider a scenario where there a two topics T1 and T2 and two consumers C1 and C2. C1 consumes only from T1 and C2 only from T2. Say if C2 dies for some reason as explained before, C1 will get a watcher event from zookeeper and a synced rebalance will be triggered. Why does C2 dying which has absolutely nothing with C1 (there is no intersection of topics between C1 and C2) should trigger a rebalance event in C1. Is there some condition where this is necessary that I am missing? Thanks, Dinesh
