HDFS-12082. BlockInvalidateLimit value is incorrectly set after namenode heartbeat interval reconfigured. Contributed by Weiwei Yang.

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

@@ -269,12 +269,19 @@ public class DatanodeManager {
         DFSConfigKeys.DFS_NAMENODE_HEARTBEAT_RECHECK_INTERVAL_DEFAULT); // 5 minutes
     this.heartbeatExpireInterval = 2 * heartbeatRecheckInterval
         + 10 * 1000 * heartbeatIntervalSeconds;
-    final int blockInvalidateLimit = Math.max(20*(int)(heartbeatIntervalSeconds),
+
+    // Effected block invalidate limit is the bigger value between
+    // value configured in hdfs-site.xml, and 20 * HB interval.
+    final int configuredBlockInvalidateLimit = conf.getInt(
+        DFSConfigKeys.DFS_BLOCK_INVALIDATE_LIMIT_KEY,
         DFSConfigKeys.DFS_BLOCK_INVALIDATE_LIMIT_DEFAULT);
-    this.blockInvalidateLimit = conf.getInt(
+    final int countedBlockInvalidateLimit = 20*(int)(heartbeatIntervalSeconds);
-        DFSConfigKeys.DFS_BLOCK_INVALIDATE_LIMIT_KEY, blockInvalidateLimit);
+    this.blockInvalidateLimit = Math.max(countedBlockInvalidateLimit,
+        configuredBlockInvalidateLimit);
     LOG.info(DFSConfigKeys.DFS_BLOCK_INVALIDATE_LIMIT_KEY
-        + "=" + this.blockInvalidateLimit);
+        + ": configured=" + configuredBlockInvalidateLimit
+        + ", counted=" + countedBlockInvalidateLimit
+        + ", effected=" + blockInvalidateLimit);
 
     this.checkIpHostnameInRegistration = conf.getBoolean(
         DFSConfigKeys.DFS_NAMENODE_DATANODE_REGISTRATION_IP_HOSTNAME_CHECK_KEY,
@@ -382,7 +389,8 @@ public class DatanodeManager {
     return fsClusterStats;
   }
 
-  int getBlockInvalidateLimit() {
+  @VisibleForTesting
+  public int getBlockInvalidateLimit() {
     return blockInvalidateLimit;
   }
 
@@ -1812,7 +1820,7 @@ public class DatanodeManager {
     this.heartbeatExpireInterval = 2L * recheckInterval + 10 * 1000
         * intervalSeconds;
     this.blockInvalidateLimit = Math.max(20 * (int) (intervalSeconds),
-        DFSConfigKeys.DFS_BLOCK_INVALIDATE_LIMIT_DEFAULT);
+        blockInvalidateLimit);
   }
 
   /**

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

@@ -40,6 +40,7 @@ import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_HEARTBEAT_INTERVAL_KEY;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_HEARTBEAT_INTERVAL_DEFAULT;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_NAMENODE_HEARTBEAT_RECHECK_INTERVAL_KEY;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_NAMENODE_HEARTBEAT_RECHECK_INTERVAL_DEFAULT;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_BLOCK_INVALIDATE_LIMIT_KEY;
 import static org.apache.hadoop.fs.CommonConfigurationKeys.IPC_BACKOFF_ENABLE_DEFAULT;
 
 public class TestNameNodeReconfigure {
@@ -48,10 +49,13 @@ public class TestNameNodeReconfigure {
       .getLog(TestNameNodeReconfigure.class);
 
   private MiniDFSCluster cluster;
+  private final int customizedBlockInvalidateLimit = 500;
 
   @Before
   public void setUp() throws IOException {
     Configuration conf = new HdfsConfiguration();
+    conf.setInt(DFS_BLOCK_INVALIDATE_LIMIT_KEY,
+        customizedBlockInvalidateLimit);
     cluster = new MiniDFSCluster.Builder(conf).build();
     cluster.waitActive();
   }
@@ -201,6 +205,38 @@ public class TestNameNodeReconfigure {
         datanodeManager.getHeartbeatRecheckInterval());
   }
 
+  @Test
+  public void testBlockInvalidateLimitAfterReconfigured()
+      throws ReconfigurationException {
+    final NameNode nameNode = cluster.getNameNode();
+    final DatanodeManager datanodeManager = nameNode.namesystem
+        .getBlockManager().getDatanodeManager();
+
+    assertEquals(DFS_BLOCK_INVALIDATE_LIMIT_KEY + " is not correctly set",
+        customizedBlockInvalidateLimit,
+        datanodeManager.getBlockInvalidateLimit());
+
+    nameNode.reconfigureProperty(DFS_HEARTBEAT_INTERVAL_KEY,
+        Integer.toString(6));
+
+    // 20 * 6 = 120 < 500
+    // Invalid block limit should stay same as before after reconfiguration.
+    assertEquals(DFS_BLOCK_INVALIDATE_LIMIT_KEY
+            + " is not honored after reconfiguration",
+        customizedBlockInvalidateLimit,
+        datanodeManager.getBlockInvalidateLimit());
+
+    nameNode.reconfigureProperty(DFS_HEARTBEAT_INTERVAL_KEY,
+        Integer.toString(50));
+
+    // 20 * 50 = 1000 > 500
+    // Invalid block limit should be reset to 1000
+    assertEquals(DFS_BLOCK_INVALIDATE_LIMIT_KEY
+            + " is not reconfigured correctly",
+        1000,
+        datanodeManager.getBlockInvalidateLimit());
+  }
+
   @After
   public void shutDown() throws IOException {
     if (cluster != null) {