Time for action – the fourth and last run

Let's perform the fourth execution to validate that the output has now reached its final stable state.

  1. Execute the MapReduce job:
    $ hadoop jar graph.jarGraphPathgraphout3graphout4
    
  2. Examine the output file:
    $ hadoop fs -cat /user/hadoop/graphout4/part-r-00000
    12,3,40D
    21,41D
    31,5,61D
    41,21D
    53,62D
    63,52D
    76-1P
    

What just happened?

The output is as expected; since node 7 is not reachable by node 1 or any of its neighbors, it will remain Pending and never be processed further. Consequently, our graph is unchanged as shown in the following figure:

What just happened?

The one thing we did not build into our algorithm was an understanding ...

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