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How can you set the mappers and reducers for a MapReduce job?
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How can you set the mappers and reducers for a MapReduce job?
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asked
Nov 24, 2020
in
Hadoop
by
rahuljain1
How can you set the mappers and reducers for a MapReduce job?
#reducers
#mapreduce-reducers
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answered
Nov 24, 2020
by
sharadyadav1986
The number of mappers and reducers can be set in the command line using:
-D mapred.map.tasks=5 –D mapred.reduce.tasks=2
In the code, one can configure JobConf variables:
job.setNumMapTasks(5); // 5 mappers
job.setNumReduceTasks(2); // 2 reducers
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