Matthias J. Sax created KAFKA-6399:
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             Summary: Consider reducing "max.poll.interval.ms" default for 
Kafka Streams
                 Key: KAFKA-6399
                 URL: https://issues.apache.org/jira/browse/KAFKA-6399
             Project: Kafka
          Issue Type: Bug
          Components: streams
    Affects Versions: 1.0.0
            Reporter: Matthias J. Sax
            Priority: Minor


In Kafka {{0.10.2.1}} we change the default value of {{max.poll.intervall.ms}} 
for Kafka Streams to {{Integer.MAX_VALUE}}. The reason was that long state 
restore phases during rebalance could yield "rebalance storms" as consumers 
drop out of a consumer group even if they are healthy as they didn't call 
{{poll()}} during state restore phase.

In version {{0.11}} and {{1.0}} the state restore logic was improved a lot and 
thus, now Kafka Streams does call {{poll()}} even during restore phase. 
Therefore, we might consider setting a smaller timeout for 
{{max.poll.intervall.ms}} to detect bad behaving Kafka Streams applications 
(ie, targeting user code) that don't make progress any more during regular 
operations.

The open question would be, what a good default might be. Maybe the actual 
consumer default of 30 seconds might be sufficient. During one {{poll()}} 
roundtrip, we would only call {{restoreConsumer.poll()}} once and restore a 
single batch of records. This should take way less time than 30 seconds.



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