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Jiangjie Qin commented on KAFKA-345: ------------------------------------ Updated reviewboard https://reviews.apache.org/r/28025/diff/ against branch origin/trunk > Add a listener to ZookeeperConsumerConnector to get notified on rebalance > events > -------------------------------------------------------------------------------- > > Key: KAFKA-345 > URL: https://issues.apache.org/jira/browse/KAFKA-345 > Project: Kafka > Issue Type: Improvement > Components: core > Affects Versions: 0.7, 0.8.0 > Reporter: Peter Romianowski > Attachments: KAFKA-345.patch, KAFKA-345.patch, > KAFKA-345_2014-11-15_01:00:55.patch > > > A sample use-case > In our scenario we partition events by userid and then apply these to some > kind of state machine, that modifies the actual state of a user. So events > trigger state transitions. In order to avoid the need of loading user's state > upon each event processed, we cache that. But if a user's partition is moved > to another consumer and then back to the previous consumer we have stale > caches and hell breaks loose. I guess the same kind of problem occurs in > other scenarios like counting numbers by user, too. -- This message was sent by Atlassian JIRA (v6.3.4#6332)