HDFS-4521. Invalid network toploogies should not be cached. Contributed by Colin Patrick McCabe.


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MAPREDUCE-4990. Construct debug strings conditionally in ShuffleHandler.Shuffle#sendMapOutput(). (kkambatl via tucu)

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MAPREDUCE-5028. Maps fail when io.sort.mb is set to high value. (kkambatl via tucu)

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YARN-485. TestProcfsProcessTree#testProcessTree() doesn't wait long enough for the process to die. (kkambatl via tucu)

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Merge remote branch 'origin/branch-2' into branch-2-gd