Hi,
   Which file contains all this code ? I am looking at the file TeraSort.java 
but
this contains code for creating a trie. Similarly the file MergeSort.java
contains code for simple sequential merge sort. Where is this map reduce code ?


Best Regards from Buffalo

Abhishek Agrawal

SUNY- Buffalo
(716-435-7122)

On Fri 02/19/10  5:06 PM , Gang Luo [email protected] sent:
> Hi,
> the sorting is done by the MapReduce framework. At map side, the output
> record will first go to a sorting buffer where the sorting, partitioning
> and combining (if there is combiner) happen. If necessary, multi-phase
> sorting is done to make a single sorted result for each map task. At reduce
> side, all the data from multiple map tasks will be merged (each of them is
> sorted at the map side, you only need merge sort here). It goes multiple
> rounds if necessary.
> -Gang
> 
> 
> 
> ----- ���件 ----
> �件人� "aa...@buffa
> lo.edu" <aa...@buffa
> lo.edu>æ�¶ä»¶äººï¼� [email protected]å��é��æ�¥æ��ï¼� 2010/2/19
> (��) 2:25:50 ��主   �� Some information on
> Hadoop Sort
> Hello,
> I was wondering if some one could me some information on hadoop does
> thesorting. From what I have read there does not seem to be a map class and
> reduceclass ? Where and how is the sorting parallelized ?
> 
> 
> Best Regards from Buffalo
> 
> Abhishek Agrawal
> 
> SUNY- Buffalo
> (716-435-7122)
> 
> 
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