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


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1457883 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-4990. Construct debug strings conditionally in ShuffleHandler.Shuffle#sendMapOutput(). (kkambatl via tucu)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1457916 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-5028. Maps fail when io.sort.mb is set to high value. (kkambatl via tucu)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1457919 13f79535-47bb-0310-9956-ffa450edef68
YARN-485. TestProcfsProcessTree#testProcessTree() doesn't wait long enough for the process to die. (kkambatl via tucu)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1457938 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/branch-2' into branch-2-gd
Merge remote branch 'origin/branch-2-gd' into fb-MAPREDUCE-4884-branch-2-gd