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Kafka >> mail # user >> Persist Queue On HDFS


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Re: Persist Queue On HDFS
Nice idea, but different sort of animal.  Going to HDFS is different.  It requires aggregation of traffic, so there is the whole offset commit strategy concern.  When pulling traffic for per message work, we commit after every pull, so exactly once.  The tradeoff with aggregation is whether to allow for at-lease once, or have some traffic loss under extreme conditions.  We chose the later since we felt it occurs less often and rarely.  So we still commit after every message and if the rack falls over, we lose a couple of hundred (thousand ?) messages.  We could always replay manually, from the last successful offset, as we have that info available, somewhere, whereas duplication requires pruning.  Plus it seems to avoid the shutdown fetcher syndrome.  A concurrent writer to hdfs is helpful, so there is lower latency, just split the traffic into queues.  We go for the second time to prod in 3 days.

Is there anyway to use the high level consumer and read chunks of traffic through the KafkaStream, at a time?

Thank you,
Robert
On Jan 14, 2014, at 2:16 PM, Blender Bl <[EMAIL PROTECTED]> wrote:

>
> Hi,
>
>
> My team trying to implement lambda architecture.
> We need to stream all our new data though Kafka to storm, and HDFS.
>
>
> As i see it were are two options:
>
> Using Camus - not very efficent
> Streaming via Storm - not very efficent
>
> Is it possible to persist the queue's files over the HDFS (with short-circuit setting switched on) instead of the local filesystem?
>
>
> It suppose to have similar performance to the local file system, doesn't it?
- rob