Merge 1563640 from trunk: HDFS-5828. BlockPlacementPolicyWithNodeGroup can place multiple replicas on the same node group when dfs.namenode.avoid.write.stale.datanode is true. (Buddy via junping_du)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1563643 13f79535-47bb-0310-9956-ffa450edef68

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -38,6 +38,10 @@ Release 2.4.0 - UNRELEASED
     HDFS-5856. DataNode.checkDiskError might throw NPE.
     (Josh Elser via suresh)
 
+    HDFS-5828. BlockPlacementPolicyWithNodeGroup can place multiple replicas on
+    the same node group when dfs.namenode.avoid.write.stale.datanode is true. 
+    (Buddy via junping_du)
+
 Release 2.3.0 - UNRELEASED
 
   INCOMPATIBLE CHANGES

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/BlockPlacementPolicyDefault.java

@@ -317,7 +317,7 @@ public class BlockPlacementPolicyDefault extends BlockPlacementPolicy {
         // We need to additionally exclude the nodes that were added to the 
         // result list in the successful calls to choose*() above.
         for (DatanodeStorageInfo resultStorage : results) {
-          oldExcludedNodes.add(resultStorage.getDatanodeDescriptor());
+          addToExcludedNodes(resultStorage.getDatanodeDescriptor(), oldExcludedNodes);
         }
         // Set numOfReplicas, since it can get out of sync with the result list
         // if the NotEnoughReplicasException was thrown in chooseRandom().

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/blockmanagement/TestReplicationPolicyWithNodeGroup.java

@@ -124,6 +124,8 @@ public class TestReplicationPolicyWithNodeGroup {
     CONF.set(CommonConfigurationKeysPublic.NET_TOPOLOGY_IMPL_KEY, 
         NetworkTopologyWithNodeGroup.class.getName());
     
+    CONF.setBoolean(DFSConfigKeys.DFS_NAMENODE_AVOID_STALE_DATANODE_FOR_WRITE_KEY, true);
+    
     File baseDir = PathUtils.getTestDir(TestReplicationPolicyWithNodeGroup.class);
     
     CONF.set(DFSConfigKeys.DFS_NAMENODE_NAME_DIR_KEY,