HDFS-2708. Stats for the # of blocks per DN. Contributed by Aaron T. Myers.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1326039 13f79535-47bb-0310-9956-ffa450edef68

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

@@ -377,6 +377,8 @@ Release 2.0.0 - UNRELEASED
     HDFS-3259. NameNode#initializeSharedEdits should populate shared edits dir
     with edit log segments. (atm)
 
+    HDFS-2708. Stats for the # of blocks per DN. (atm)
+
   OPTIMIZATIONS
 
     HDFS-3024. Improve performance of stringification in addStoredBlock (todd)

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java

@@ -5051,6 +5051,7 @@ public class FSNamesystem implements Namesystem, FSClusterStats,
       innerinfo.put("adminState", node.getAdminState().toString());
       innerinfo.put("nonDfsUsedSpace", node.getNonDfsUsed());
       innerinfo.put("capacity", node.getCapacity());
+      innerinfo.put("numBlocks", node.numBlocks());
       info.put(node.getHostName(), innerinfo);
     }
     return JSON.toString(info);

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestNameNodeMXBean.java

@@ -101,6 +101,8 @@ public class TestNameNodeMXBean {
         assertTrue(((Long)liveNode.get("nonDfsUsedSpace")) > 0);
         assertTrue(liveNode.containsKey("capacity"));
         assertTrue(((Long)liveNode.get("capacity")) > 0);
+        assertTrue(liveNode.containsKey("numBlocks"));
+        assertTrue(((Long)liveNode.get("numBlocks")) == 0);
       }
       Assert.assertEquals(fsn.getLiveNodes(), alivenodeinfo);
       // get attribute deadnodeinfo