HDFS-14960. TestBalancerWithNodeGroup should not succeed with DFSNetworkTopology. Contributed by Jim Brennan.

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/balancer/TestBalancerWithNodeGroup.java

@@ -18,6 +18,8 @@
 package org.apache.hadoop.hdfs.server.balancer;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.assertFalse;
 
 import java.io.IOException;
 import java.net.URI;
@@ -44,11 +46,12 @@
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
 import org.apache.hadoop.hdfs.protocol.LocatedBlocks;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants.DatanodeReportType;
+import org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicy;
 import org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyWithNodeGroup;
+import org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementStatus;
 import org.apache.hadoop.net.NetworkTopology;
 import org.apache.hadoop.net.NetworkTopologyWithNodeGroup;
 import org.apache.hadoop.test.LambdaTestUtils;
-import org.junit.Assert;
 import org.junit.Test;
 
 /**
@@ -192,8 +195,8 @@ private void runBalancerCanFinish(Configuration conf,
     // start rebalancing
     Collection<URI> namenodes = DFSUtil.getInternalNsRpcUris(conf);
     final int r = Balancer.run(namenodes, BalancerParameters.DEFAULT, conf);
-    Assert.assertTrue(r == ExitStatus.SUCCESS.getExitCode() ||
+    assertEquals("Balancer did not exit with NO_MOVE_PROGRESS",
-        (r == ExitStatus.NO_MOVE_PROGRESS.getExitCode()));
+        ExitStatus.NO_MOVE_PROGRESS.getExitCode(), r);
     waitForHeartBeat(totalUsedSpace, totalCapacity);
     LOG.info("Rebalancing with default factor.");
   }
@@ -211,6 +214,30 @@ private Set<ExtendedBlock> getBlocksOnRack(List<LocatedBlock> blks, String rack)
     return ret;
   }
 
+  private void verifyNetworkTopology() {
+    NetworkTopology topology =
+        cluster.getNamesystem().getBlockManager().getDatanodeManager().
+            getNetworkTopology();
+    assertTrue("must be an instance of NetworkTopologyWithNodeGroup",
+        topology instanceof NetworkTopologyWithNodeGroup);
+  }
+
+  private void verifyProperBlockPlacement(String file,
+      long length, int numOfReplicas) throws IOException {
+    BlockPlacementPolicy placementPolicy =
+        cluster.getNamesystem().getBlockManager().getBlockPlacementPolicy();
+    List<LocatedBlock> locatedBlocks = client.
+        getBlockLocations(file, 0, length).getLocatedBlocks();
+    assertFalse("No blocks found for file " + file, locatedBlocks.isEmpty());
+    for (LocatedBlock locatedBlock : locatedBlocks) {
+      BlockPlacementStatus status = placementPolicy.verifyBlockPlacement(
+          locatedBlock.getLocations(), numOfReplicas);
+      assertTrue("Block placement policy was not satisfied for block " +
+          locatedBlock.getBlock().getBlockId(),
+          status.isPlacementPolicySatisfied());
+    }
+  }
+
   /**
    * Create a cluster with even distribution, and a new empty node is added to
    * the cluster, then test rack locality for balancer policy. 
@@ -232,6 +259,7 @@ public void testBalancerWithRackLocality() throws Exception {
     cluster = new MiniDFSClusterWithNodeGroup(builder);
     try {
       cluster.waitActive();
+      verifyNetworkTopology();
       client = NameNodeProxies.createProxy(conf, 
           cluster.getFileSystem(0).getUri(),
           ClientProtocol.class).getProxy();
@@ -258,12 +286,14 @@ public void testBalancerWithRackLocality() throws Exception {
       totalCapacity += newCapacity;
 
       // run balancer and validate results
-      runBalancerCanFinish(conf, totalUsedSpace, totalCapacity);
+      runBalancer(conf, totalUsedSpace, totalCapacity);
       
       lbs = client.getBlockLocations(filePath.toUri().getPath(), 0, length);
       Set<ExtendedBlock> after = getBlocksOnRack(lbs.getLocatedBlocks(), RACK0);
       assertEquals(before, after);
 
+      verifyProperBlockPlacement(filePath.toUri().getPath(), length,
+          numOfDatanodes);
     } finally {
       cluster.shutdown();
     }
@@ -291,15 +321,18 @@ public void testBalancerWithNodeGroup() throws Exception {
     cluster = new MiniDFSClusterWithNodeGroup(builder);
     try {
       cluster.waitActive();
+      verifyNetworkTopology();
       client = NameNodeProxies.createProxy(conf, 
           cluster.getFileSystem(0).getUri(),
           ClientProtocol.class).getProxy();
 
       long totalCapacity = TestBalancer.sum(capacities);
+      int numOfReplicas = numOfDatanodes / 2;
       // fill up the cluster to be 20% full
       long totalUsedSpace = totalCapacity * 2 / 10;
-      TestBalancer.createFile(cluster, filePath, totalUsedSpace / (numOfDatanodes/2),
+      long length = totalUsedSpace / numOfReplicas;
-          (short) (numOfDatanodes/2), 0);
+      TestBalancer.createFile(cluster, filePath, length,
+          (short) numOfReplicas, 0);
       
       long newCapacity = CAPACITY;
       String newRack = RACK1;
@@ -313,6 +346,9 @@ public void testBalancerWithNodeGroup() throws Exception {
       // run balancer and validate results
       runBalancer(conf, totalUsedSpace, totalCapacity);
 
+      verifyProperBlockPlacement(filePath.toUri().getPath(), length,
+          numOfReplicas);
+
     } finally {
       cluster.shutdown();
     }
@@ -345,6 +381,7 @@ public void testBalancerEndInNoMoveProgress() throws Exception {
     cluster = new MiniDFSClusterWithNodeGroup(builder);
     try {
       cluster.waitActive();
+      verifyNetworkTopology();
       client = NameNodeProxies.createProxy(conf, 
           cluster.getFileSystem(0).getUri(),
           ClientProtocol.class).getProxy();
@@ -352,12 +389,17 @@ public void testBalancerEndInNoMoveProgress() throws Exception {
       long totalCapacity = TestBalancer.sum(capacities);
       // fill up the cluster to be 60% full
       long totalUsedSpace = totalCapacity * 6 / 10;
-      TestBalancer.createFile(cluster, filePath, totalUsedSpace / 3, 
+      int numOfReplicas = 3;
-          (short) (3), 0);
+      long length = totalUsedSpace / 3;
+      TestBalancer.createFile(cluster, filePath, length,
+          (short) numOfReplicas, 0);
 
       // run balancer which can finish in 5 iterations with no block movement.
       runBalancerCanFinish(conf, totalUsedSpace, totalCapacity);
 
+      verifyProperBlockPlacement(filePath.toUri().getPath(), length,
+          numOfReplicas);
+
     } finally {
       cluster.shutdown();
     }