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Re: Multiple reducers
Hi Hoot

You can specify the number of reducers explicitly using -D
mapred.reduce.tasks=n.

hadoop jar wordcount.jar com.wc.WordCount –D mapred.reduce.tasks=n /input
/output

Currenty your word count is triggering just 1 reducer because the defaukt
value of mapred.reduce.tasks woulld be set as 1 in your configuration file

Hope it helps !.

Regards
Bejoy.K.S

On Tue, Nov 29, 2011 at 8:03 PM, Hoot Thompson <[EMAIL PROTECTED]> wrote:

> I'm trying to prove that my cluster will in fact support multiple reducers,
> the wordcount example doesn't seem to spawn more that one (1). Is that
> correct? Is there a sure fire way to prove my cluster is configured
> correctly in terms of launching the maximum (say two per node) number of
> mappers and reducers?
>
> Thanks!
>
>
>
NEW: Monitor These Apps!
elasticsearch, apache solr, apache hbase, hadoop, redis, casssandra, amazon cloudwatch, mysql, memcached, apache kafka, apache zookeeper, apache storm, ubuntu, centOS, red hat, debian, puppet labs, java, senseiDB