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Re: Hive Query Unable to distribute load evenly in reducers
And your queries were?

On Mon, Oct 15, 2012 at 8:09 PM, Saurabh Mishra
> Hi,
> I am firing some hive queries joining tables containing upto 30millions
> records each. Since the load on the reducers is very significant in these
> cases, i specifically set the following parameters before executing the
> queries :
> set mapred.reduce.tasks=100;
> set hive.exec.reducers.bytes.per.reducer=500000000;
> set hive.optimize.cp=true;
> The number of reducer the job spouts in now 160, but despite the high number
> most of the load remains upon 1 or 2 reducers. Hence in the final
> statistics, 158 reducers go completed with 2-3 minutes of start and 2
> reducers took 2 hrs to run.
> Is there any way to overcome this load distribution disparity.
> Any help in this regards will be highly appreciated.
> Sincerely
> Saurabh Mishra