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MapReduce >> mail # user >> Passing messages


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Re: Passing messages
In your reducer, you can utilize Reporter (getCounter and incrCounter
methods) to pass this information between reducers.

On Sat, Dec 18, 2010 at 8:04 AM, Martin Becker <[EMAIL PROTECTED]> wrote:

> Hello everbody,
>
> I am wondering if there is a feature allowing (in my case) reduce
> tasks to communicate. For example by some volatile variables at some
> centralized point. Or maybe just notify other running or to-be-running
> reduce tasks of a completed reduce task featuring some arguments.
>
> In my case, I have reduce tasks doing computations that will
> output/produce certain quality threshold. Other reduce tasks can/could
> estimate, if they ever get above those thresholds. If not they could
> just cease running.
>
> Thanks in advance,
> Martin
>
> PS: If such functions are not yet part of the API, I would like to
> know if there are good reasons for it and if not, propose to introduce
> such functionality.
>