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https://issues.apache.org/jira/browse/KAFKA-2350?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14643442#comment-14643442
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Jason Gustafson commented on KAFKA-2350:
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[~becket_qin] I think that we're on the same page as far as supporting only
automatic or manual assignment and not trying to mix them. I think my confusion
is that subscribe(partition) in your proposal is used both a) to subscribe to a
partition when manual assignment is used, and b) to unpause a partition when
automatic assignment is used. This leads to the weird ordering problems that we
have been talking about. By the way, I added the line about seek() and
position() since it seems like something that intuitively should be supported
by pause semantics. I think it's debatable whether it's really needed, but I
think it would cause a bit a surprise to the user if we didn't allow it.
> Add KafkaConsumer pause capability
> ----------------------------------
>
> Key: KAFKA-2350
> URL: https://issues.apache.org/jira/browse/KAFKA-2350
> Project: Kafka
> Issue Type: Improvement
> Reporter: Jason Gustafson
> Assignee: Jason Gustafson
>
> There are some use cases in stream processing where it is helpful to be able
> to pause consumption of a topic. For example, when joining two topics, you
> may need to delay processing of one topic while you wait for the consumer of
> the other topic to catch up. The new consumer currently doesn't provide a
> nice way to do this. If you skip calls to poll() or if you unsubscribe, then
> a rebalance will be triggered and your partitions will be reassigned to
> another consumer. The desired behavior is instead that you keep the partition
> assigned and simply
> One way to achieve this would be to add two new methods to KafkaConsumer:
> {code}
> void pause(TopicPartition... partitions);
> void resume(TopicPartition... partitions);
> {code}
> Here is the expected behavior of pause/resume:
> * When a partition is paused, calls to KafkaConsumer.poll will not initiate
> any new fetches for that partition.
> * After the partition is resumed, fetches will begin again.
> * While a partition is paused, seek() and position() can still be used to
> advance or query the current position.
> * Rebalance does not preserve pause/resume state.
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