HDFS-15665. Balancer logging improvements. Contributed by Konstantin V Shvachko.

(cherry picked from commit d07dc7afb4aa0d6cc9f9be530802e54610776a4d)

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/balancer/Balancer.java

@@ -282,6 +282,9 @@ public class Balancer {
    */
   Balancer(NameNodeConnector theblockpool, BalancerParameters p,
       Configuration conf) {
+    // NameNode configuration parameters for balancing
+    getInt(conf, DFSConfigKeys.DFS_NAMENODE_GETBLOCKS_MAX_QPS_KEY,
+        DFSConfigKeys.DFS_NAMENODE_GETBLOCKS_MAX_QPS_DEFAULT);
     final long movedWinWidth = getLong(conf,
         DFSConfigKeys.DFS_BALANCER_MOVEDWINWIDTH_KEY,
         DFSConfigKeys.DFS_BALANCER_MOVEDWINWIDTH_DEFAULT);
@@ -291,10 +294,6 @@ public class Balancer {
     final int dispatcherThreads = getInt(conf,
         DFSConfigKeys.DFS_BALANCER_DISPATCHERTHREADS_KEY,
         DFSConfigKeys.DFS_BALANCER_DISPATCHERTHREADS_DEFAULT);
-    final int maxConcurrentMovesPerNode = getInt(conf,
-        DFSConfigKeys.DFS_DATANODE_BALANCE_MAX_NUM_CONCURRENT_MOVES_KEY,
-        DFSConfigKeys.DFS_DATANODE_BALANCE_MAX_NUM_CONCURRENT_MOVES_DEFAULT);
-
     final long getBlocksSize = getLongBytes(conf,
         DFSConfigKeys.DFS_BALANCER_GETBLOCKS_SIZE_KEY,
         DFSConfigKeys.DFS_BALANCER_GETBLOCKS_SIZE_DEFAULT);
@@ -311,6 +310,13 @@ public class Balancer {
         DFSConfigKeys.DFS_BALANCER_MAX_ITERATION_TIME_KEY,
         DFSConfigKeys.DFS_BALANCER_MAX_ITERATION_TIME_DEFAULT);
 
+    // DataNode configuration parameters for balancing
+    final int maxConcurrentMovesPerNode = getInt(conf,
+        DFSConfigKeys.DFS_DATANODE_BALANCE_MAX_NUM_CONCURRENT_MOVES_KEY,
+        DFSConfigKeys.DFS_DATANODE_BALANCE_MAX_NUM_CONCURRENT_MOVES_DEFAULT);
+    getLongBytes(conf, DFSConfigKeys.DFS_DATANODE_BALANCE_BANDWIDTHPERSEC_KEY,
+        DFSConfigKeys.DFS_DATANODE_BALANCE_BANDWIDTHPERSEC_DEFAULT);
+
     this.nnc = theblockpool;
     this.dispatcher =
         new Dispatcher(theblockpool, p.getIncludedNodes(),
@@ -603,12 +609,13 @@ public class Balancer {
       this.bytesAlreadyMoved = bytesAlreadyMoved;
     }
 
-    void print(int iteration, PrintStream out) {
-      out.printf("%-24s %10d  %19s  %18s  %17s%n",
+    void print(int iteration, NameNodeConnector nnc, PrintStream out) {
+      out.printf("%-24s %10d  %19s  %18s  %17s  %s%n",
           DateFormat.getDateTimeInstance().format(new Date()), iteration,
           StringUtils.byteDesc(bytesAlreadyMoved),
           StringUtils.byteDesc(bytesLeftToMove),
-          StringUtils.byteDesc(bytesBeingMoved));
+          StringUtils.byteDesc(bytesBeingMoved),
+          nnc.getNameNodeUri());
     }
   }
 
@@ -653,8 +660,10 @@ public class Balancer {
         System.out.println("No block can be moved. Exiting...");
         return newResult(ExitStatus.NO_MOVE_BLOCK, bytesLeftToMove, bytesBeingMoved);
       } else {
-        LOG.info( "Will move " + StringUtils.byteDesc(bytesBeingMoved) +
-            " in this iteration");
+        LOG.info("Will move {}  in this iteration for {}",
+            StringUtils.byteDesc(bytesBeingMoved), nnc.toString());
+        LOG.info("Total target DataNodes in this iteration: {}",
+            dispatcher.moveTasksTotal());
       }
 
       /* For each pair of <source, target>, start a thread that repeatedly 
@@ -705,7 +714,9 @@ public class Balancer {
     LOG.info("excluded nodes = " + p.getExcludedNodes());
     LOG.info("source nodes = " + p.getSourceNodes());
     checkKeytabAndInit(conf);
-    System.out.println("Time Stamp               Iteration#  Bytes Already Moved  Bytes Left To Move  Bytes Being Moved");
+    System.out.println("Time Stamp               Iteration#"
+        + "  Bytes Already Moved  Bytes Left To Move  Bytes Being Moved"
+        + "  NameNode");
     
     List<NameNodeConnector> connectors = Collections.emptyList();
     try {
@@ -721,7 +732,7 @@ public class Balancer {
               || p.getBlockPools().contains(nnc.getBlockpoolID())) {
             final Balancer b = new Balancer(nnc, p, conf);
             final Result r = b.runOneIteration();
-            r.print(iteration, System.out);
+            r.print(iteration, nnc, System.out);
 
             // clean all lists
             b.resetData(conf);

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/balancer/Dispatcher.java

@@ -392,7 +392,7 @@ public class Dispatcher {
 
         sendRequest(out, eb, accessToken);
         receiveResponse(in);
-        nnc.getBytesMoved().addAndGet(reportedBlock.getNumBytes());
+        nnc.addBytesMoved(reportedBlock.getNumBytes());
         target.getDDatanode().setHasSuccess();
         LOG.info("Successfully moved " + this);
       } catch (IOException e) {
@@ -1064,6 +1064,10 @@ public class Dispatcher {
     return nnc.getBytesMoved().get();
   }
 
+  long getBblocksMoved() {
+    return nnc.getBlocksMoved().get();
+  }
+
   long bytesToMove() {
     Preconditions.checkState(
         storageGroupMap.size() >= sources.size() + targets.size(),
@@ -1083,6 +1087,14 @@ public class Dispatcher {
     targets.add(target);
   }
 
+  public int moveTasksTotal() {
+    int b = 0;
+    for (Source src : sources) {
+      b += src.tasks.size();
+    }
+    return b;
+  }
+
   private boolean shouldIgnore(DatanodeInfo dn) {
     // ignore out-of-service nodes
     final boolean outOfService = !dn.isInService();
@@ -1164,12 +1176,13 @@ public class Dispatcher {
    */
   private long dispatchBlockMoves() throws InterruptedException {
     final long bytesLastMoved = getBytesMoved();
+    final long blocksLastMoved = getBblocksMoved();
     final Future<?>[] futures = new Future<?>[sources.size()];
 
     int concurrentThreads = Math.min(sources.size(),
         ((ThreadPoolExecutor)dispatchExecutor).getCorePoolSize());
     assert concurrentThreads > 0 : "Number of concurrent threads is 0.";
-    LOG.debug("Balancer concurrent dispatcher threads = {}", concurrentThreads);
+    LOG.info("Balancer concurrent dispatcher threads = {}", concurrentThreads);
 
     // Determine the size of each mover thread pool per target
     int threadsPerTarget = maxMoverThreads/targets.size();
@@ -1211,6 +1224,9 @@ public class Dispatcher {
 
     // wait for all reportedBlock moving to be done
     waitForMoveCompletion(targets);
+    LOG.info("Total bytes (blocks) moved in this iteration {} ({})",
+        StringUtils.byteDesc(getBytesMoved() - bytesLastMoved),
+        (getBblocksMoved() - blocksLastMoved));
 
     return getBytesMoved() - bytesLastMoved;
   }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/balancer/NameNodeConnector.java

@@ -162,6 +162,7 @@ public class NameNodeConnector implements Closeable {
   private OutputStream out;
   private final List<Path> targetPaths;
   private final AtomicLong bytesMoved = new AtomicLong();
+  private final AtomicLong blocksMoved = new AtomicLong();
 
   private final int maxNotChangedIterations;
   private int notChangedIterations = 0;
@@ -233,6 +234,19 @@ public class NameNodeConnector implements Closeable {
     return bytesMoved;
   }
 
+  AtomicLong getBlocksMoved() {
+    return blocksMoved;
+  }
+
+  public void addBytesMoved(long numBytes) {
+    bytesMoved.addAndGet(numBytes);
+    blocksMoved.incrementAndGet();
+  }
+
+  public URI getNameNodeUri() {
+    return nameNodeUri;
+  }
+
   /** @return blocks with locations. */
   public BlocksWithLocations getBlocks(DatanodeInfo datanode, long size, long
       minBlockSize) throws IOException {

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

@@ -1018,7 +1018,7 @@ public class TestBalancer {
         for(NameNodeConnector nnc : connectors) {
           final Balancer b = new Balancer(nnc, p, conf);
           final Result r = b.runOneIteration();
-          r.print(iteration, System.out);
+          r.print(iteration, nnc, System.out);
 
           // clean all lists
           b.resetData(conf);