HADOOP-9451. Fault single-layer config if node group topology is enabled. (Junping Du via llu)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1464301 13f79535-47bb-0310-9956-ffa450edef68

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -165,6 +165,9 @@ Trunk (Unreleased)
 
   BUG FIXES
 
+    HADOOP-9451. Fault single-layer config if node group topology is enabled.
+    (Junping Du via llu)
+
     HADOOP-8419. Fixed GzipCode NPE reset for IBM JDK. (Yu Li via eyang)
 
     HADOOP-9041. FsUrlStreamHandlerFactory could cause an infinite loop in

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/net/NetworkTopologyWithNodeGroup.java

@@ -191,7 +191,12 @@ public class NetworkTopologyWithNodeGroup extends NetworkTopology {
       }
       rack = getNode(nodeGroup.getNetworkLocation());
 
-      if (rack != null && !(rack instanceof InnerNode)) {
+      // rack should be an innerNode and with parent.
+      // note: rack's null parent case is: node's topology only has one layer, 
+      //       so rack is recognized as "/" and no parent. 
+      // This will be recognized as a node with fault topology.
+      if (rack != null && 
+          (!(rack instanceof InnerNode) || rack.getParent() == null)) {
         throw new IllegalArgumentException("Unexpected data node " 
             + node.toString() 
             + " at an illegal network location");

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/net/TestNetworkTopologyWithNodeGroup.java

@@ -0,0 +1,200 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.net;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.junit.Test;
+
+public class TestNetworkTopologyWithNodeGroup {
+  private final static NetworkTopologyWithNodeGroup cluster = new 
+      NetworkTopologyWithNodeGroup();
+
+  private final static NodeBase dataNodes[] = new NodeBase[] {
+      new NodeBase("h1", "/d1/r1/s1"),
+      new NodeBase("h2", "/d1/r1/s1"),
+      new NodeBase("h3", "/d1/r1/s2"),
+      new NodeBase("h4", "/d1/r2/s3"),
+      new NodeBase("h5", "/d1/r2/s3"),
+      new NodeBase("h6", "/d1/r2/s4"),
+      new NodeBase("h7", "/d2/r3/s5"),
+      new NodeBase("h8", "/d2/r3/s6")
+  };
+
+  private final static NodeBase computeNode = new NodeBase("/d1/r1/s1/h9");
+  
+  private final static NodeBase rackOnlyNode = new NodeBase("h10", "/r2");
+
+  static {
+    for(int i=0; i<dataNodes.length; i++) {
+      cluster.add(dataNodes[i]);
+    }
+  }
+
+  @Test
+  public void testNumOfChildren() throws Exception {
+    assertEquals(cluster.getNumOfLeaves(), dataNodes.length);
+  }
+
+  @Test
+  public void testNumOfRacks() throws Exception {
+    assertEquals(cluster.getNumOfRacks(), 3);
+  }
+
+  @Test
+  public void testRacks() throws Exception {
+    assertEquals(cluster.getNumOfRacks(), 3);
+    assertTrue(cluster.isOnSameRack(dataNodes[0], dataNodes[1]));
+    assertTrue(cluster.isOnSameRack(dataNodes[1], dataNodes[2]));
+    assertFalse(cluster.isOnSameRack(dataNodes[2], dataNodes[3]));
+    assertTrue(cluster.isOnSameRack(dataNodes[3], dataNodes[4]));
+    assertTrue(cluster.isOnSameRack(dataNodes[4], dataNodes[5]));
+    assertFalse(cluster.isOnSameRack(dataNodes[5], dataNodes[6]));
+    assertTrue(cluster.isOnSameRack(dataNodes[6], dataNodes[7]));
+  }
+
+  @Test
+  public void testNodeGroups() throws Exception {
+    assertEquals(cluster.getNumOfRacks(), 3);
+    assertTrue(cluster.isOnSameNodeGroup(dataNodes[0], dataNodes[1]));
+    assertFalse(cluster.isOnSameNodeGroup(dataNodes[1], dataNodes[2]));
+    assertFalse(cluster.isOnSameNodeGroup(dataNodes[2], dataNodes[3]));
+    assertTrue(cluster.isOnSameNodeGroup(dataNodes[3], dataNodes[4]));
+    assertFalse(cluster.isOnSameNodeGroup(dataNodes[4], dataNodes[5]));
+    assertFalse(cluster.isOnSameNodeGroup(dataNodes[5], dataNodes[6]));
+    assertFalse(cluster.isOnSameNodeGroup(dataNodes[6], dataNodes[7]));
+  }
+
+  @Test
+  public void testGetDistance() throws Exception {
+    assertEquals(cluster.getDistance(dataNodes[0], dataNodes[0]), 0);
+    assertEquals(cluster.getDistance(dataNodes[0], dataNodes[1]), 2);
+    assertEquals(cluster.getDistance(dataNodes[0], dataNodes[2]), 4);
+    assertEquals(cluster.getDistance(dataNodes[0], dataNodes[3]), 6);
+    assertEquals(cluster.getDistance(dataNodes[0], dataNodes[6]), 8);
+  }
+
+  @Test
+  public void testPseudoSortByDistance() throws Exception {
+    NodeBase[] testNodes = new NodeBase[4];
+
+    // array contains both local node, local node group & local rack node
+    testNodes[0] = dataNodes[1];
+    testNodes[1] = dataNodes[2];
+    testNodes[2] = dataNodes[3];
+    testNodes[3] = dataNodes[0];
+    cluster.pseudoSortByDistance(dataNodes[0], testNodes );
+    assertTrue(testNodes[0] == dataNodes[0]);
+    assertTrue(testNodes[1] == dataNodes[1]);
+    assertTrue(testNodes[2] == dataNodes[2]);
+    assertTrue(testNodes[3] == dataNodes[3]);
+
+    // array contains local node & local node group
+    testNodes[0] = dataNodes[3];
+    testNodes[1] = dataNodes[4];
+    testNodes[2] = dataNodes[1];
+    testNodes[3] = dataNodes[0];
+    cluster.pseudoSortByDistance(dataNodes[0], testNodes );
+    assertTrue(testNodes[0] == dataNodes[0]);
+    assertTrue(testNodes[1] == dataNodes[1]);
+
+    // array contains local node & rack node
+    testNodes[0] = dataNodes[5];
+    testNodes[1] = dataNodes[3];
+    testNodes[2] = dataNodes[2];
+    testNodes[3] = dataNodes[0];
+    cluster.pseudoSortByDistance(dataNodes[0], testNodes );
+    assertTrue(testNodes[0] == dataNodes[0]);
+    assertTrue(testNodes[1] == dataNodes[2]);
+
+    // array contains local-nodegroup node (not a data node also) & rack node
+    testNodes[0] = dataNodes[6];
+    testNodes[1] = dataNodes[7];
+    testNodes[2] = dataNodes[2];
+    testNodes[3] = dataNodes[0];
+    cluster.pseudoSortByDistance(computeNode, testNodes );
+    assertTrue(testNodes[0] == dataNodes[0]);
+    assertTrue(testNodes[1] == dataNodes[2]);
+  }
+
+  /**
+   * This picks a large number of nodes at random in order to ensure coverage
+   * 
+   * @param numNodes the number of nodes
+   * @param excludedScope the excluded scope
+   * @return the frequency that nodes were chosen
+   */
+  private Map<Node, Integer> pickNodesAtRandom(int numNodes,
+      String excludedScope) {
+    Map<Node, Integer> frequency = new HashMap<Node, Integer>();
+    for (NodeBase dnd : dataNodes) {
+      frequency.put(dnd, 0);
+    }
+
+    for (int j = 0; j < numNodes; j++) {
+      Node random = cluster.chooseRandom(excludedScope);
+      frequency.put(random, frequency.get(random) + 1);
+    }
+    return frequency;
+  }
+
+  /**
+   * This test checks that chooseRandom works for an excluded node.
+   */
+  /**
+   * Test replica placement policy in case last node is invalid.
+   * We create 6 nodes but the last node is in fault topology (with rack info),
+   * so cannot be added to cluster. We should test proper exception is thrown in 
+   * adding node but shouldn't affect the cluster.
+   */
+  @Test
+  public void testChooseRandomExcludedNode() {
+    String scope = "~" + NodeBase.getPath(dataNodes[0]);
+    Map<Node, Integer> frequency = pickNodesAtRandom(100, scope);
+
+    for (Node key : dataNodes) {
+      // all nodes except the first should be more than zero
+      assertTrue(frequency.get(key) > 0 || key == dataNodes[0]);
+    }
+  }
+  
+  /**
+   * This test checks that adding a node with invalid topology will be failed 
+   * with an exception to show topology is invalid.
+   */
+  @Test
+  public void testAddNodeWithInvalidTopology() {
+    // The last node is a node with invalid topology
+    try {
+      cluster.add(rackOnlyNode);
+      fail("Exception should be thrown, so we should not have reached here.");
+    } catch (Exception e) {
+      if (!(e instanceof IllegalArgumentException)) {
+        fail("Expecting IllegalArgumentException, but caught:" + e);
+      }
+      assertTrue(e.getMessage().contains("illegal network location"));
+    }
+  }
+
+}