HDFS-657. Remove unused legacy data-node protocol methods. Contributed by Konstantin Shvachko.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/hdfs/branches/HDFS-265@819243 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -15,6 +15,8 @@ Append branch (unreleased changes)
    HDFS-570. Get last block length from a data-node when opening a file
    being written to. (Tsz Wo (Nicholas), SZE via shv)
 
+   HDFS-657. Remove unused legacy data-node protocol methods. (shv)
+
   NEW FEATURES
 
     HDFS-536. Support hflush at DFSClient. (hairong)

src/java/org/apache/hadoop/hdfs/protocol/ClientDatanodeProtocol.java

@@ -29,22 +29,9 @@ public interface ClientDatanodeProtocol extends VersionedProtocol {
   public static final Log LOG = LogFactory.getLog(ClientDatanodeProtocol.class);
 
   /**
-   * 5: add getReplicaVisibleLength(..)
+   * 6: recoverBlock() removed.
    */
-  public static final long versionID = 5L;
-
-  /** Start generation-stamp recovery for specified block
-   * @param block the specified block
-   * @param keepLength keep the block length
-   * @param targets the list of possible locations of specified block
-   * @return either a new generation stamp, or the original generation stamp. 
-   * Regardless of whether a new generation stamp is returned, a newly 
-   * generated access token is returned as part of the return value.
-   * @throws IOException
-   */
-  @Deprecated // not used anymore - should be removed
-  LocatedBlock recoverBlock(Block block, boolean keepLength,
-      DatanodeInfo[] targets) throws IOException;
+  public static final long versionID = 6L;
 
   /** Return the visible length of a replica. */
   long getReplicaVisibleLength(Block b) throws IOException;

src/java/org/apache/hadoop/hdfs/server/datanode/DataNode.java

@@ -36,10 +36,8 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.EnumSet;
-import java.util.HashMap;
 import java.util.LinkedList;
 import java.util.List;
-import java.util.Map;
 import java.util.Random;
 import java.util.concurrent.atomic.AtomicInteger;
 
@@ -58,7 +56,6 @@ import org.apache.hadoop.hdfs.protocol.FSConstants;
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
 import org.apache.hadoop.hdfs.protocol.UnregisteredNodeException;
 import org.apache.hadoop.hdfs.protocol.DataTransferProtocol.BlockConstructionStage;
-import org.apache.hadoop.hdfs.server.common.GenerationStamp;
 import org.apache.hadoop.hdfs.server.common.HdfsConstants;
 import org.apache.hadoop.hdfs.server.common.IncorrectVersionException;
 import org.apache.hadoop.hdfs.server.common.Storage;
@@ -172,8 +169,6 @@ public class DataNode extends Configured
 
   volatile boolean shouldRun = true;
   private LinkedList<Block> receivedBlockList = new LinkedList<Block>();
-  /** list of blocks being recovered */
-  private final Map<Block, Block> ongoingRecovery = new HashMap<Block, Block>();
   private LinkedList<String> delHints = new LinkedList<String>();
   public final static String EMPTY_DEL_HINT = "";
   AtomicInteger xmitsInProgress = new AtomicInteger();
@@ -1587,55 +1582,36 @@ public class DataNode extends Configured
     Block block = rBlock.getBlock();
     DatanodeInfo[] targets = rBlock.getLocations();
     DatanodeID[] datanodeids = (DatanodeID[])targets;
-    // If the block is already being recovered, then skip recovering it.
-    // This can happen if the namenode and client start recovering the same
-    // file at the same time.
-    synchronized (ongoingRecovery) {
-      if (ongoingRecovery.get(new Block(block.getBlockId(), block.getNumBytes(), 
-          GenerationStamp.WILDCARD_STAMP)) != null) {
-        String msg = "Block " + block + " is already being recovered, " +
-                     " ignoring this request to recover it.";
-        LOG.info(msg);
-        throw new IOException(msg);
-      }
-      ongoingRecovery.put(block, block);
-    }
-    try {
-      List<BlockRecord> syncList = new ArrayList<BlockRecord>();
-      long minlength = Long.MAX_VALUE;
-      int errorCount = 0;
+    List<BlockRecord> syncList = new ArrayList<BlockRecord>();
+    long minlength = Long.MAX_VALUE;
+    int errorCount = 0;
 
-      //check generation stamps
-      for(DatanodeID id : datanodeids) {
-        try {
-          InterDatanodeProtocol datanode = dnRegistration.equals(id)?
-              this: DataNode.createInterDataNodeProtocolProxy(id, getConf());
-          BlockMetaDataInfo info = datanode.getBlockMetaDataInfo(block);
-          if (info != null && info.getGenerationStamp() >= block.getGenerationStamp()) {
-            syncList.add(new BlockRecord(id, datanode, new Block(info)));
-            if (info.getNumBytes() < minlength) {
-              minlength = info.getNumBytes();
-            }
+    //check generation stamps
+    for(DatanodeID id : datanodeids) {
+      try {
+        InterDatanodeProtocol datanode = dnRegistration.equals(id)?
+            this: DataNode.createInterDataNodeProtocolProxy(id, getConf());
+        BlockMetaDataInfo info = datanode.getBlockMetaDataInfo(block);
+        if (info != null && info.getGenerationStamp() >= block.getGenerationStamp()) {
+          syncList.add(new BlockRecord(id, datanode, new Block(info)));
+          if (info.getNumBytes() < minlength) {
+            minlength = info.getNumBytes();
           }
-        } catch (IOException e) {
-          ++errorCount;
-          InterDatanodeProtocol.LOG.warn(
-              "Failed to getBlockMetaDataInfo for block (=" + block 
-              + ") from datanode (=" + id + ")", e);
         }
+      } catch (IOException e) {
+        ++errorCount;
+        InterDatanodeProtocol.LOG.warn(
+            "Failed to getBlockMetaDataInfo for block (=" + block 
+            + ") from datanode (=" + id + ")", e);
       }
+    }
 
-      if (syncList.isEmpty() && errorCount > 0) {
-        throw new IOException("All datanodes failed: block=" + block
-            + ", datanodeids=" + Arrays.asList(datanodeids));
-      }
-      block.setNumBytes(minlength);
-      return syncBlock(rBlock, syncList);
-    } finally {
-      synchronized (ongoingRecovery) {
-        ongoingRecovery.remove(block);
-      }
+    if (syncList.isEmpty() && errorCount > 0) {
+      throw new IOException("All datanodes failed: block=" + block
+          + ", datanodeids=" + Arrays.asList(datanodeids));
     }
+    block.setNumBytes(minlength);
+    return syncBlock(rBlock, syncList);
   }
 
   /** Block synchronization */
@@ -1706,16 +1682,6 @@ public class DataNode extends Configured
         + syncList.size() + " datanodes success {" + b + "\n}");
   }
   
-  // ClientDataNodeProtocol implementation
-  /** {@inheritDoc} */
-  @SuppressWarnings("deprecation")
-  public LocatedBlock recoverBlock(Block block, boolean keepLength, DatanodeInfo[] targets
-      ) throws IOException {
-    logRecoverBlock("Client", block, targets);
-    assert false : "ClientDatanodeProtocol.recoverBlock: should never be called.";
-    return null;
-  }
-
   private static void logRecoverBlock(String who,
       Block block, DatanodeID[] targets) {
     StringBuilder msg = new StringBuilder(targets[0].getName());
@@ -1726,8 +1692,9 @@ public class DataNode extends Configured
         + ", targets=[" + msg + "])");
   }
 
+  // ClientDataNodeProtocol implementation
   /** {@inheritDoc} */
-  @Override
+  @Override // ClientDataNodeProtocol
   public long getReplicaVisibleLength(final Block block) throws IOException {
     final Replica replica = data.getReplica(block.getBlockId());
     if (replica == null) {

src/java/org/apache/hadoop/hdfs/server/namenode/BlockInfo.java

@@ -307,7 +307,6 @@ class BlockInfo extends Block {
     BlockInfoUnderConstruction ucBlock = (BlockInfoUnderConstruction)this;
     ucBlock.setBlockUCState(s);
     ucBlock.setExpectedLocations(targets);
-    ucBlock.setLastRecoveryTime(0);
     return ucBlock;
   }
 

src/java/org/apache/hadoop/hdfs/server/namenode/BlockInfoUnderConstruction.java

@@ -42,9 +42,6 @@ class BlockInfoUnderConstruction extends BlockInfo {
   /** A data-node responsible for block recovery. */
   private int primaryNodeIndex = -1;
 
-  /** The last time the block was recovered. */
-  private long lastRecoveryTime = 0;
-
   /**
    * The new generation stamp, which this block will have
    * after the recovery succeeds. Also used as a recovery id to identify
@@ -234,18 +231,6 @@ class BlockInfoUnderConstruction extends BlockInfo {
     }
   }
 
-  /**
-   * Update lastRecoveryTime if expired.
-   * @return true if lastRecoveryTimeis updated. 
-   */
-  boolean setLastRecoveryTime(long now) {
-    boolean expired = now - lastRecoveryTime > NameNode.LEASE_RECOVER_PERIOD;
-    if (expired) {
-      lastRecoveryTime = now;
-    }
-    return expired;
-  }
-
   void addReplicaIfNotPresent(DatanodeDescriptor dn,
                      Block block,
                      ReplicaState rState) {
@@ -275,7 +260,6 @@ class BlockInfoUnderConstruction extends BlockInfo {
      .append("\n  blockUCState=").append(blockUCState)
      .append("\n  replicas=").append(replicas)
      .append("\n  primaryNodeIndex=").append(primaryNodeIndex)
-     .append("\n  lastRecoveryTime=").append(lastRecoveryTime)
      .append("}");
     return b.toString();
   }

src/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java

@@ -3866,33 +3866,6 @@ public class FSNamesystem implements FSConstants, FSNamesystemMBean, FSClusterSt
     return gs;
   }
 
-  /**
-   * Verifies that the block is associated with a file that has a lease.
-   * Increments, logs and then returns the stamp
-   */
-  synchronized long nextGenerationStampForBlock(Block block) throws IOException {
-    BlockInfo storedBlock = blockManager.getStoredBlock(block);
-    if (storedBlock == null) {
-      String msg = block + " is already commited, storedBlock == null.";
-      LOG.info(msg);
-      throw new IOException(msg);
-    }
-    INodeFile fileINode = storedBlock.getINode();
-    if(!fileINode.isUnderConstruction() || storedBlock.isComplete()) {
-      String msg = block + 
-            " is already commited, file or block is not under construction().";
-      LOG.info(msg);
-      throw new IOException(msg);
-    }
-    if(!((BlockInfoUnderConstruction)storedBlock).setLastRecoveryTime(now())) {
-      String msg = block + " is beening recovered, ignoring this request.";
-      LOG.info(msg);
-      throw new IOException(msg);
-    }
-    return nextGenerationStamp();
-  }
-
-
   private INodeFileUnderConstruction checkUCBlock(Block block, String clientName) 
   throws IOException {
     // check safe mode

src/java/org/apache/hadoop/hdfs/server/namenode/NameNode.java

@@ -667,10 +667,6 @@ public class NameNode implements ClientProtocol, DatanodeProtocol,
   }
 
   /** {@inheritDoc} */
-  public long nextGenerationStamp(Block block) throws IOException{
-    return namesystem.nextGenerationStampForBlock(block);
-  }
-
   @Override
   public LocatedBlock updateBlockForPipeline(Block block, String clientName)
   throws IOException {

src/java/org/apache/hadoop/hdfs/server/protocol/DatanodeProtocol.java

@@ -35,9 +35,9 @@ import org.apache.hadoop.ipc.VersionedProtocol;
  **********************************************************************/
 public interface DatanodeProtocol extends VersionedProtocol {
   /**
-   * 22: BlockRecoveryCommand introduced in reply to sendHeartbeat().
+   * 23: nextGenerationStamp() removed.
    */
-  public static final long versionID = 22L;
+  public static final long versionID = 23L;
   
   // error code
   final static int NOTIFY = 0;
@@ -141,12 +141,6 @@ public interface DatanodeProtocol extends VersionedProtocol {
    */
   public void reportBadBlocks(LocatedBlock[] blocks) throws IOException;
   
-  /**
-   * @return the next GenerationStamp to be associated with the specified
-   * block. 
-   */
-  public long nextGenerationStamp(Block block) throws IOException;
-
   /**
    * Commit block synchronization in lease recovery
    */