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From Edward Smith <esm...@stardotstar.org>
Subject Consumer State Description in design.html
Date Fri, 13 Apr 2012 17:04:52 GMT
I didn't want to open up a bug unless there was some concurrence on
this.   Please review the change below and see if I'm just
misunderstanding things or not.  This paragraph in the doc took me a
long time to digest because it was describing the contrib/hadoop
consumer and not how simpleconsumer or consoleconsumer work:

Consumer State (the second heading like this in the file)

In Kafka, the consumers are responsible for maintaining state
information on what has been consumed.  The core Kafka consumers write
their state data to zookeeper.

However, it may be beneficial for consumers to write state data into
the same datastore where they are writing the results of their
processing.  For example, the consumer may simply be entering some
aggregate value into a centralized...... (rest of section remains the
same from here)


On Fri, Apr 13, 2012 at 12:02 PM, Jun Rao <junrao@gmail.com> wrote:
> Currently, as you are iterating messages returned by SimpleConsumer, you
> also get the offset for the next message. In the map, you can just run for
> 30 mins and save the next offset for the next run.
> Thanks,
> Jun
> On Fri, Apr 13, 2012 at 1:01 AM, R S <mypostboxat@gmail.com> wrote:
>> Hi ,
>> I looked at hadoop-consumer , which fetches data directly from the kafka
>> broker . But from what i understand it is based on min and max offset and
>> map task complete once they reach the maximum offset for a given topic .
>> In our use case we would not know about the max offset before hand. Instead
>> we want map to keep reading data from a min offset and roll over every 30
>> mins . At 30th min we would again generate the offsets which would be used
>> for the next run.
>> any suggestions would be helpful .
>> regards,
>> rks

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