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https://issues.apache.org/jira/browse/SPARK-10320?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Cody Koeninger updated SPARK-10320:
-----------------------------------
    Summary: Kafka Support new topic subscriptions without requiring restart of 
the streaming context  (was: Support new topic subscriptions without requiring 
restart of the streaming context)

> Kafka Support new topic subscriptions without requiring restart of the 
> streaming context
> ----------------------------------------------------------------------------------------
>
>                 Key: SPARK-10320
>                 URL: https://issues.apache.org/jira/browse/SPARK-10320
>             Project: Spark
>          Issue Type: New Feature
>          Components: Streaming
>            Reporter: Sudarshan Kadambi
>
> Spark Streaming lacks the ability to subscribe to newer topics or unsubscribe 
> to current ones once the streaming context has been started. Restarting the 
> streaming context increases the latency of update handling.
> Consider a streaming application subscribed to n topics. Let's say 1 of the 
> topics is no longer needed in streaming analytics and hence should be 
> dropped. We could do this by stopping the streaming context, removing that 
> topic from the topic list and restarting the streaming context. Since with 
> some DStreams such as DirectKafkaStream, the per-partition offsets are 
> maintained by Spark, we should be able to resume uninterrupted (I think?) 
> from where we left off with a minor delay. However, in instances where 
> expensive state initialization (from an external datastore) may be needed for 
> datasets published to all topics, before streaming updates can be applied to 
> it, it is more convenient to only subscribe or unsubcribe to the incremental 
> changes to the topic list. Without such a feature, updates go unprocessed for 
> longer than they need to be, thus affecting QoS.



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