Question

Here is an example:

Is it possible to have same mapper run against multiple reducers at the same time? like

map output : {1:[1,2,3,4,5,4,3,2], 4:[5,4,6,7,8,9,5,3,3,2], 3:[1,5,4,3,5,6,7,8,9,1], so on}  

reducer1 : sum of all numbers  
reducer2 : average of all numbers  
reducer3 : mode of all numbers   

act on the the same key like  

reducer1 output: {1:sum of values, 2:sum of values, and so on}  
reducer2 output: {1:avg of values, 2: avg of values and so on}
reducer3 output: {1:mode of values, 2: mode of values, and so on}  

and so on..Please let me know.

Answer 1

I really wanted to answer this for you but it’s already been asked. Hadoop one Map and multiple Reduce