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https://issues.apache.org/jira/browse/KAFKA-519?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Manikumar resolved KAFKA-519.
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    Resolution: Auto Closed

Closing inactive issue. The old consumer is no longer supported.


> Allow commiting the state of single KafkaStream
> -----------------------------------------------
>
>                 Key: KAFKA-519
>                 URL: https://issues.apache.org/jira/browse/KAFKA-519
>             Project: Kafka
>          Issue Type: Improvement
>    Affects Versions: 0.7, 0.7.1
>            Reporter: Esko Suomi
>            Priority: Minor
>
> Currently consuming multiple topics through ZK by first acquiring 
> ConsumerConnector and then fetching message streams for wanted topics. And 
> when the messages have been consumed, the current consuming state is commited 
> with the method ConsumerConnector#commitOffsets().
> This scheme has a flaw when the consuming application is used as sort of a 
> data piping proxy instead of final consuming sink. In our case we read data 
> from Kafka, repackage it and only then move it to persistent storage. The 
> repackaging step is relatively long running and may span several hours 
> (usually a few minutes) which in addition is mixed with highly asymmetric 
> topic throughputs; one of our topics gets about 80% of total throughput. We 
> have about 20 topics in total. As an unwanted side effect of all this, 
> commiting the offset whenever the per-topic persistence step has been taken 
> means commiting offsets for other topics too which may eventually manifest as 
> loss of data if the consuming application or the machine it is running on 
> crashes.
> So, while this loss of data can be alleviated to some extent with for example 
> local temp storage, it would be cleaner if KafkaStream itself would allow for 
> partition level offset commiting.



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