Following the instructions on this link, I implemented a wordcount program in c++ using single mapper and single reducer. Now I need to use two mappers and one reducer for the same problem.
Can someone help me please in this regard?
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The number of mappers depends on the number of input splits created. The number of input splits depends on the size of the input, the size of a block, the number of input files (each input file creates at least one input split), whether the input files are splittable or not, etc. See also this post in SO.
You can set the number of reducers to as many as you wish. I guess in hadoop pipes you can do this by setting the -D mapred.reduce.tasks=... when running hadoop. See this post in SO.
If you want to quickly test how your program works with more than one mappers, you can simply put a new file in your input path. This will make hadoop create another input split and thus another map task.
PS: The link that you provide is not reachable.
