the ut of the pr

Author: singer-bin

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/impl/BlockPoolSlice.java

@@ -235,6 +235,7 @@ public void run() {
   }
 
   public void refreshSpaceUsedKlass(Configuration conf) throws IOException {
+    ((CachingGetSpaceUsed)dfsUsage).close();
     this.dfsUsage = new FSCachingGetSpaceUsed.Builder().setBpid(bpid)
             .setVolume(volume)
             .setPath(bpDir)

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestDataNodeReconfiguration.java

@@ -18,6 +18,8 @@
 
 package org.apache.hadoop.hdfs.server.datanode;
 
+import org.apache.hadoop.fs.CachingGetSpaceUsed;
+import static org.apache.hadoop.fs.CommonConfigurationKeysPublic.FS_GETSPACEUSED_CLASSNAME;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_BLOCKREPORT_INITIAL_DELAY_KEY;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_BLOCKREPORT_INTERVAL_MSEC_DEFAULT;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_BLOCKREPORT_INTERVAL_MSEC_KEY;
@@ -76,6 +78,7 @@ public class TestDataNodeReconfiguration {
   private final int NUM_NAME_NODE = 1;
   private final int NUM_DATA_NODE = 10;
   private MiniDFSCluster cluster;
+  private static long counter = 0;
 
   @Before
   public void Setup() throws IOException {
@@ -99,6 +102,7 @@ private void startDFSCluster(int numNameNodes, int numDataNodes)
       throws IOException {
     Configuration conf = new Configuration();
     conf.setBoolean(DFS_DATANODE_PEER_STATS_ENABLED_KEY, true);
+    conf.set(FS_GETSPACEUSED_CLASSNAME, DummyDU.class.getName());
 
     MiniDFSNNTopology nnTopology = MiniDFSNNTopology
         .simpleFederatedTopology(numNameNodes);
@@ -673,4 +677,32 @@ public void testSlowDiskParameters() throws ReconfigurationException, IOExceptio
           dn.getDiskMetrics().getSlowDiskDetector().getLowThresholdMs());
     }
   }
+
+  private static class DummyDU extends CachingGetSpaceUsed {
+    public DummyDU(Builder builder) throws IOException {
+      super(builder.setInterval(1000));
+    }
+
+    @Override
+    protected void refresh() {
+      counter++;
+    }
+  }
+
+  @Test
+  public void testDfsUsageParameters() throws IOException, ReconfigurationException, InterruptedException {
+    final DataNode[] dns = createDNsForTest(1);
+    final DataNode dataNode = dns[0];
+
+    long lastCounter = counter;
+
+    Thread.sleep(5000);
+    assertTrue(counter > lastCounter);
+
+    dataNode.reconfigurePropertyImpl(FS_GETSPACEUSED_CLASSNAME, null);
+
+    lastCounter = counter;
+    Thread.sleep(5000);
+    assertEquals(lastCounter, counter);
+  }
 }