HDFS-13222. Update getBlocks method to take minBlockSize in RPC calls. Contributed by Bharat Viswanadham

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocolPB/NamenodeProtocolServerSideTranslatorPB.java

@@ -86,7 +86,8 @@ public class NamenodeProtocolServerSideTranslatorPB implements
         .build();
     BlocksWithLocations blocks;
     try {
-      blocks = impl.getBlocks(dnInfo, request.getSize());
+      blocks = impl.getBlocks(dnInfo, request.getSize(),
+          request.getMinBlockSize());
     } catch (IOException e) {
       throw new ServiceException(e);
     }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocolPB/NamenodeProtocolTranslatorPB.java

@@ -99,11 +99,12 @@ public class NamenodeProtocolTranslatorPB implements NamenodeProtocol,
   }
 
   @Override
-  public BlocksWithLocations getBlocks(DatanodeInfo datanode, long size)
+  public BlocksWithLocations getBlocks(DatanodeInfo datanode, long size, long
+      minBlockSize)
       throws IOException {
     GetBlocksRequestProto req = GetBlocksRequestProto.newBuilder()
         .setDatanode(PBHelperClient.convert((DatanodeID)datanode)).setSize(size)
-        .build();
+        .setMinBlockSize(minBlockSize).build();
     try {
       return PBHelper.convert(rpcProxy.getBlocks(NULL_CONTROLLER, req)
           .getBlocks());

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

@@ -785,7 +785,7 @@ public class Dispatcher {
     private long getBlockList() throws IOException {
       final long size = Math.min(getBlocksSize, blocksToReceive);
       final BlocksWithLocations newBlksLocs =
-          nnc.getBlocks(getDatanodeInfo(), size);
+          nnc.getBlocks(getDatanodeInfo(), size, getBlocksMinBlockSize);
 
       if (LOG.isTraceEnabled()) {
         LOG.trace("getBlocks(" + getDatanodeInfo() + ", "

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

@@ -162,9 +162,10 @@ public class NameNodeConnector implements Closeable {
   }
 
   /** @return blocks with locations. */
-  public BlocksWithLocations getBlocks(DatanodeInfo datanode, long size)
+  public BlocksWithLocations getBlocks(DatanodeInfo datanode, long size, long
+      minBlockSize)
       throws IOException {
-    return namenode.getBlocks(datanode, size);
+    return namenode.getBlocks(datanode, size, minBlockSize);
   }
 
   /**

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

@@ -408,13 +408,6 @@ public class BlockManager implements BlockStatsMXBean {
    */
   private int numBlocksPerIteration;
 
-  /**
-   * Minimum size that a block can be sent to Balancer through getBlocks.
-   * And after HDFS-8824, the small blocks are unused anyway, so there's no
-   * point to send them to balancer.
-   */
-  private long getBlocksMinBlockSize = -1;
-
   /**
    * Progress of the Reconstruction queues initialisation.
    */
@@ -539,9 +532,6 @@ public class BlockManager implements BlockStatsMXBean {
     this.numBlocksPerIteration = conf.getInt(
         DFSConfigKeys.DFS_BLOCK_MISREPLICATION_PROCESSING_LIMIT,
         DFSConfigKeys.DFS_BLOCK_MISREPLICATION_PROCESSING_LIMIT_DEFAULT);
-    this.getBlocksMinBlockSize = conf.getLongBytes(
-        DFSConfigKeys.DFS_BALANCER_GETBLOCKS_MIN_BLOCK_SIZE_KEY,
-        DFSConfigKeys.DFS_BALANCER_GETBLOCKS_MIN_BLOCK_SIZE_DEFAULT);
 
     final int minMaintenanceR = conf.getInt(
         DFSConfigKeys.DFS_NAMENODE_MAINTENANCE_REPLICATION_MIN_KEY,
@@ -1469,7 +1459,8 @@ public class BlockManager implements BlockStatsMXBean {
 
   /** Get all blocks with location information from a datanode. */
   public BlocksWithLocations getBlocksWithLocations(final DatanodeID datanode,
-      final long size) throws UnregisteredNodeException {
+      final long size, final long minBlockSize) throws
+      UnregisteredNodeException {
     final DatanodeDescriptor node = getDatanodeManager().getDatanode(datanode);
     if (node == null) {
       blockLog.warn("BLOCK* getBlocks: Asking for blocks from an" +
@@ -1491,7 +1482,7 @@ public class BlockManager implements BlockStatsMXBean {
     while(totalSize<size && iter.hasNext()) {
       curBlock = iter.next();
       if(!curBlock.isComplete())  continue;
-      if (curBlock.getNumBytes() < getBlocksMinBlockSize) {
+      if (curBlock.getNumBytes() < minBlockSize) {
         continue;
       }
       totalSize += addBlock(curBlock, results);
@@ -1501,7 +1492,7 @@ public class BlockManager implements BlockStatsMXBean {
       for(int i=0; i<startBlock&&totalSize<size; i++) {
         curBlock = iter.next();
         if(!curBlock.isComplete())  continue;
-        if (curBlock.getNumBytes() < getBlocksMinBlockSize) {
+        if (curBlock.getNumBytes() < minBlockSize) {
           continue;
         }
         totalSize += addBlock(curBlock, results);

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java

@@ -1718,13 +1718,14 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
    * @param datanode on which blocks are located
    * @param size total size of blocks
    */
-  public BlocksWithLocations getBlocks(DatanodeID datanode, long size)
-      throws IOException {
+  public BlocksWithLocations getBlocks(DatanodeID datanode, long size, long
+      minimumBlockSize) throws IOException {
     checkOperation(OperationCategory.READ);
     readLock();
     try {
       checkOperation(OperationCategory.READ);
-      return getBlockManager().getBlocksWithLocations(datanode, size);
+      return getBlockManager().getBlocksWithLocations(datanode, size,
+          minimumBlockSize);
     } finally {
       readUnlock("getBlocks");
     }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNodeRpcServer.java

@@ -618,15 +618,20 @@ public class NameNodeRpcServer implements NamenodeProtocols {
   // NamenodeProtocol
   /////////////////////////////////////////////////////
   @Override // NamenodeProtocol
-  public BlocksWithLocations getBlocks(DatanodeInfo datanode, long size)
-  throws IOException {
+  public BlocksWithLocations getBlocks(DatanodeInfo datanode, long size, long
+      minBlockSize)
+      throws IOException {
     if(size <= 0) {
       throw new IllegalArgumentException(
-        "Unexpected not positive size: "+size);
+          "Unexpected not positive size: "+size);
+    }
+    if(minBlockSize < 0) {
+      throw new IllegalArgumentException(
+          "Unexpected not positive size: "+size);
     }
     checkNNStartup();
     namesystem.checkSuperuserPrivilege();
-    return namesystem.getBlocks(datanode, size);
+    return namesystem.getBlocks(datanode, size, minBlockSize);
   }
 
   @Override // NamenodeProtocol

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/protocol/NamenodeProtocol.java

@@ -67,17 +67,18 @@ public interface NamenodeProtocol {
   /**
    * Get a list of blocks belonging to <code>datanode</code>
    * whose total size equals <code>size</code>.
-   * 
+   *
    * @see org.apache.hadoop.hdfs.server.balancer.Balancer
    * @param datanode  a data node
    * @param size      requested size
+   * @param minBlockSize each block should be of this minimum Block Size
    * @return          a list of blocks & their locations
    * @throws IOException if size is less than or equal to 0 or
-                                   datanode does not exist
+  datanode does not exist
    */
   @Idempotent
-  public BlocksWithLocations getBlocks(DatanodeInfo datanode, long size)
-  throws IOException;
+  BlocksWithLocations getBlocks(DatanodeInfo datanode, long size, long
+      minBlockSize) throws IOException;
 
   /**
    * Get the current block keys

hadoop-hdfs-project/hadoop-hdfs/src/main/proto/NamenodeProtocol.proto

@@ -43,6 +43,7 @@ import "HdfsServer.proto";
 message GetBlocksRequestProto {
   required DatanodeIDProto datanode = 1; // Datanode ID
   required uint64 size = 2;              // Size in bytes
+  optional uint64 minBlockSize = 3 [default = 0]; // Minimum Block Size in bytes
 }
 
  

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestGetBlocks.java

@@ -229,32 +229,48 @@ public class TestGetBlocks {
       NamenodeProtocol namenode = NameNodeProxies.createProxy(CONF,
           DFSUtilClient.getNNUri(addr), NamenodeProtocol.class).getProxy();
 
-      // get blocks of size fileLen from dataNodes[0]
+      // get blocks of size fileLen from dataNodes[0], with minBlockSize as
+      // fileLen
       BlockWithLocations[] locs;
-      locs = namenode.getBlocks(dataNodes[0], fileLen).getBlocks();
-      assertEquals(locs.length, 12);
+
+      // Should return all 13 blocks, as minBlockSize is not passed
+      locs = namenode.getBlocks(dataNodes[0], fileLen, 0)
+          .getBlocks();
+      assertEquals(13, locs.length);
+      assertEquals(locs[0].getStorageIDs().length, 2);
+      assertEquals(locs[1].getStorageIDs().length, 2);
+
+      // Should return 12 blocks, as minBlockSize is DEFAULT_BLOCK_SIZE
+      locs = namenode.getBlocks(dataNodes[0], fileLen, DEFAULT_BLOCK_SIZE)
+          .getBlocks();
+      assertEquals(12, locs.length);
       assertEquals(locs[0].getStorageIDs().length, 2);
       assertEquals(locs[1].getStorageIDs().length, 2);
 
       // get blocks of size BlockSize from dataNodes[0]
-      locs = namenode.getBlocks(dataNodes[0], DEFAULT_BLOCK_SIZE).getBlocks();
+      locs = namenode.getBlocks(dataNodes[0], DEFAULT_BLOCK_SIZE,
+          DEFAULT_BLOCK_SIZE).getBlocks();
       assertEquals(locs.length, 1);
       assertEquals(locs[0].getStorageIDs().length, 2);
 
       // get blocks of size 1 from dataNodes[0]
-      locs = namenode.getBlocks(dataNodes[0], 1).getBlocks();
+      locs = namenode.getBlocks(dataNodes[0], 1, 1).getBlocks();
       assertEquals(locs.length, 1);
       assertEquals(locs[0].getStorageIDs().length, 2);
 
       // get blocks of size 0 from dataNodes[0]
-      getBlocksWithException(namenode, dataNodes[0], 0);
+      getBlocksWithException(namenode, dataNodes[0], 0, 0);
 
       // get blocks of size -1 from dataNodes[0]
-      getBlocksWithException(namenode, dataNodes[0], -1);
+      getBlocksWithException(namenode, dataNodes[0], -1, 0);
+
+      // minBlockSize is -1
+      getBlocksWithException(namenode, dataNodes[0], DEFAULT_BLOCK_SIZE, -1);
 
       // get blocks of size BlockSize from a non-existent datanode
       DatanodeInfo info = DFSTestUtil.getDatanodeInfo("1.2.3.4");
-      getBlocksWithException(namenode, info, 2);
+      getBlocksWithIncorrectDatanodeException(namenode, info, 2, 0);
+
 
       testBlockIterator(cluster);
     } finally {
@@ -263,10 +279,24 @@ public class TestGetBlocks {
   }
 
   private void getBlocksWithException(NamenodeProtocol namenode,
-      DatanodeInfo datanode, long size) throws IOException {
+      DatanodeInfo datanode, long size, long minBlockSize) throws IOException {
+    boolean getException = false;
+    try {
+      namenode.getBlocks(datanode, size, minBlockSize);
+    } catch (RemoteException e) {
+      getException = true;
+      assertTrue(e.getClassName().contains("IllegalArgumentException"));
+    }
+    assertTrue(getException);
+  }
+
+  private void getBlocksWithIncorrectDatanodeException(
+      NamenodeProtocol namenode, DatanodeInfo datanode, long size,
+      long minBlockSize)
+      throws IOException {
     boolean getException = false;
     try {
-      namenode.getBlocks(DFSTestUtil.getLocalDatanodeInfo(), 2);
+      namenode.getBlocks(datanode, size, minBlockSize);
     } catch (RemoteException e) {
       getException = true;
       assertTrue(e.getClassName().contains("HadoopIllegalArgumentException"));

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

@@ -2072,7 +2072,7 @@ public class TestBalancer {
         endGetBlocksTime = Time.monotonicNow();
         numGetBlocksCalls++;
         return blk;
-      }}).when(fsnSpy).getBlocks(any(DatanodeID.class), anyLong());
+      }}).when(fsnSpy).getBlocks(any(DatanodeID.class), anyLong(), anyLong());
   }
 
   /**