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.
- Execute the MapReduce job:
$ hadoop jar graph.jarGraphPathgraphout3graphout4 - 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:
The one thing we did not build into our algorithm was an understanding ...
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