HADOOP-10273. Merging r1564638 from trunk to branch-2.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1564639 13f79535-47bb-0310-9956-ffa450edef68
HDFS-5709. Improve NameNode upgrade with existing reserved paths and path components. Contributed by Andrew Wang.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1564647 13f79535-47bb-0310-9956-ffa450edef68
YARN-1636. Augmented Application-history server's web-services to also expose new APIs for retrieving and storing timeline information. Contributed by Zhijie Shen.
svn merge --ignore-ancestry -c 1564829 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1564830 13f79535-47bb-0310-9956-ffa450edef68
Addendum patch for HDFS-5709, add missing license header.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1564886 13f79535-47bb-0310-9956-ffa450edef68
HDFS-5876. Merge change r1564897 from trunk.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1564904 13f79535-47bb-0310-9956-ffa450edef68
HDFS-5873. Merge change r1564973 from trunk.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1564977 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-5743. Fixed the test failure in TestRMContainerAllocator. Contributed by Vinod Kumar Vavilapalli.
svn merge --ignore-ancestry -c 1565087 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1565088 13f79535-47bb-0310-9956-ffa450edef68
YARN-1628. Fixed the test failure in TestContainerManagerSecurity. Contributed by Vinod Kumar Vavilapalli.
svn merge --ignore-ancestry -c 1565094 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1565096 13f79535-47bb-0310-9956-ffa450edef68
svn merge -c 1565310 merging from trunk to branch-2 to fix: HDFS-5881. Fix skip() of the short-circuit local reader(legacy).

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1565313 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-5699. Allow setting tags on MR jobs (kasha)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1565385 13f79535-47bb-0310-9956-ffa450edef68
HADOOP-10327. Merging change r1565389 from trunk to branch-2.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1565390 13f79535-47bb-0310-9956-ffa450edef68
YARN-1661. Fixed DS ApplicationMaster to write the correct exit log. Contributed by Vinod Kumar Vavilapalli.
svn merge --ignore-ancestry -c 1565394 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1565397 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-5743. Fixed CHANGES.txt to give credit to Ted too.
svn merge --ignore-ancestry -c 1565401 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1565402 13f79535-47bb-0310-9956-ffa450edef68
HDFS-4911. Reduce PeerCache timeout to be commensurate with dfs.datanode.socket.reuse.keepalive (cmccabe)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1565438 13f79535-47bb-0310-9956-ffa450edef68
HDFS-5895. Merging change r1565440 from trunk to branch-2.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1565442 13f79535-47bb-0310-9956-ffa450edef68
HADOOP-10273. Update CHANGES.txt to reflect new target version is 2.3 (merged r1565453 from trunk to branch-2)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1565454 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-5744. Job hangs because RMContainerAllocator.preemptReduce() violates the comparator contract (Gera Shegalov via kasha)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1565479 13f79535-47bb-0310-9956-ffa450edef68
YARN-1689. Made RMAppAttempt get killed when RMApp is at ACCEPTED. Contributed by Vinod Kumar Vavilapalli.
svn merge --ignore-ancestry -c 1565497 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1565498 13f79535-47bb-0310-9956-ffa450edef68
svn merge -c 1565505 merging from trunk to branch-2 to fix:HDFS-5807. TestBalancerWithNodeGroup.testBalancerWithNodeGroup fails intermittently.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1565506 13f79535-47bb-0310-9956-ffa450edef68
HADOOP-10330. Merging r1565507 from trunk to branch-2.

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