HDFS-7210. Avoid two separate RPC's namenode.append() and namenode.getFileInfo() for an append call from DFSClient. (Vinayakumar B via umamahesh)

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -404,6 +404,9 @@ Release 2.7.0 - UNRELEASED
     HDFS-7310. Mover can give first priority to local DN if it has target storage type 
     available in local DN. (Vinayakumar B via umamahesh)
 
+    HDFS-7210. Avoid two separate RPC's namenode.append() and namenode.getFileInfo() 
+    for an append call from DFSClient. (Vinayakumar B via umamahesh)
+
   OPTIMIZATIONS
 
   BUG FIXES

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSClient.java

@@ -163,6 +163,7 @@ import org.apache.hadoop.hdfs.protocol.HdfsConstants.DatanodeReportType;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants.RollingUpgradeAction;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants.SafeModeAction;
 import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
+import org.apache.hadoop.hdfs.protocol.LastBlockWithStatus;
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
 import org.apache.hadoop.hdfs.protocol.LocatedBlocks;
 import org.apache.hadoop.hdfs.protocol.NSQuotaExceededException;
@@ -1770,9 +1771,9 @@ public class DFSClient implements java.io.Closeable, RemotePeerFactory,
   /** Method to get stream returned by append call */
   private DFSOutputStream callAppend(String src,
       int buffersize, Progressable progress) throws IOException {
-    LocatedBlock lastBlock = null;
+    LastBlockWithStatus lastBlockWithStatus = null;
     try {
-      lastBlock = namenode.append(src, clientName);
+      lastBlockWithStatus = namenode.append(src, clientName);
     } catch(RemoteException re) {
       throw re.unwrapRemoteException(AccessControlException.class,
                                      FileNotFoundException.class,
@@ -1782,9 +1783,10 @@ public class DFSClient implements java.io.Closeable, RemotePeerFactory,
                                      UnresolvedPathException.class,
                                      SnapshotAccessControlException.class);
     }
-    HdfsFileStatus newStat = getFileInfo(src);
+    HdfsFileStatus newStat = lastBlockWithStatus.getFileStatus();
     return DFSOutputStream.newStreamForAppend(this, src, buffersize, progress,
-        lastBlock, newStat, dfsClientConf.createChecksum());
+        lastBlockWithStatus.getLastBlock(), newStat,
+        dfsClientConf.createChecksum());
   }
   
   /**

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

@@ -203,7 +203,8 @@ public interface ClientProtocol {
    * Append to the end of the file. 
    * @param src path of the file being created.
    * @param clientName name of the current client.
-   * @return information about the last partial block if any.
+   * @return wrapper with information about the last partial block and file
+   *    status if any
    * @throws AccessControlException if permission to append file is 
    * denied by the system. As usually on the client side the exception will 
    * be wrapped into {@link org.apache.hadoop.ipc.RemoteException}.
@@ -224,7 +225,7 @@ public interface ClientProtocol {
    * @throws UnsupportedOperationException if append is not supported
    */
   @AtMostOnce
-  public LocatedBlock append(String src, String clientName)
+  public LastBlockWithStatus append(String src, String clientName)
       throws AccessControlException, DSQuotaExceededException,
       FileNotFoundException, SafeModeException, UnresolvedLinkException,
       SnapshotAccessControlException, IOException;

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

@@ -0,0 +1,46 @@
+/**
+ * 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.hdfs.protocol;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.classification.InterfaceStability;
+
+/**
+ * Class to contain Lastblock and HdfsFileStatus for the Append operation
+ */
+@InterfaceAudience.Private
+@InterfaceStability.Evolving
+public class LastBlockWithStatus {
+
+  private final LocatedBlock lastBlock;
+
+  private final HdfsFileStatus fileStatus;
+
+  public LastBlockWithStatus(LocatedBlock lastBlock, HdfsFileStatus fileStatus) {
+    this.lastBlock = lastBlock;
+    this.fileStatus = fileStatus;
+  }
+
+  public LocatedBlock getLastBlock() {
+    return lastBlock;
+  }
+
+  public HdfsFileStatus getFileStatus() {
+    return fileStatus;
+  }
+}

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

@@ -35,6 +35,7 @@ import org.apache.hadoop.hdfs.protocol.CorruptFileBlocks;
 import org.apache.hadoop.hdfs.protocol.DirectoryListing;
 import org.apache.hadoop.hdfs.protocol.EncryptionZone;
 import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
+import org.apache.hadoop.hdfs.protocol.LastBlockWithStatus;
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
 import org.apache.hadoop.hdfs.protocol.LocatedBlocks;
 import org.apache.hadoop.hdfs.protocol.RollingUpgradeInfo;
@@ -247,9 +248,6 @@ public class ClientNamenodeProtocolServerSideTranslatorPB implements
   private static final CreateResponseProto VOID_CREATE_RESPONSE = 
   CreateResponseProto.newBuilder().build();
 
-  private static final AppendResponseProto VOID_APPEND_RESPONSE = 
-  AppendResponseProto.newBuilder().build();
-
   private static final SetPermissionResponseProto VOID_SET_PERM_RESPONSE = 
   SetPermissionResponseProto.newBuilder().build();
 
@@ -412,12 +410,16 @@ public class ClientNamenodeProtocolServerSideTranslatorPB implements
   public AppendResponseProto append(RpcController controller,
       AppendRequestProto req) throws ServiceException {
     try {
-      LocatedBlock result = server.append(req.getSrc(), req.getClientName());
+      LastBlockWithStatus result = server.append(req.getSrc(),
-      if (result != null) {
+          req.getClientName());
-        return AppendResponseProto.newBuilder()
+      AppendResponseProto.Builder builder = AppendResponseProto.newBuilder();
-            .setBlock(PBHelper.convert(result)).build();
+      if (result.getLastBlock() != null) {
+        builder.setBlock(PBHelper.convert(result.getLastBlock()));
       }
-      return VOID_APPEND_RESPONSE;
+      if (result.getFileStatus() != null) {
+        builder.setStat(PBHelper.convert(result.getFileStatus()));
+      }
+      return builder.build();
     } catch (IOException e) {
       throw new ServiceException(e);
     }

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

@@ -25,6 +25,7 @@ import java.util.EnumSet;
 import java.util.List;
 
 import com.google.common.collect.Lists;
+
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.crypto.CipherSuite;
@@ -63,6 +64,7 @@ import org.apache.hadoop.hdfs.protocol.HdfsConstants.DatanodeReportType;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants.RollingUpgradeAction;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants.SafeModeAction;
 import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
+import org.apache.hadoop.hdfs.protocol.LastBlockWithStatus;
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
 import org.apache.hadoop.hdfs.protocol.LocatedBlocks;
 import org.apache.hadoop.hdfs.protocol.NSQuotaExceededException;
@@ -188,7 +190,6 @@ import org.apache.hadoop.security.token.Token;
 import com.google.protobuf.ByteString;
 import com.google.protobuf.ServiceException;
 
-
 import static org.apache.hadoop.fs.BatchedRemoteIterator.BatchedListEntries;
 import static org.apache.hadoop.hdfs.protocol.proto.EncryptionZonesProtos
     .EncryptionZoneProto;
@@ -301,7 +302,7 @@ public class ClientNamenodeProtocolTranslatorPB implements
   }
 
   @Override
-  public LocatedBlock append(String src, String clientName)
+  public LastBlockWithStatus append(String src, String clientName)
       throws AccessControlException, DSQuotaExceededException,
       FileNotFoundException, SafeModeException, UnresolvedLinkException,
       IOException {
@@ -311,7 +312,11 @@ public class ClientNamenodeProtocolTranslatorPB implements
         .build();
     try {
       AppendResponseProto res = rpcProxy.append(null, req);
-      return res.hasBlock() ? PBHelper.convert(res.getBlock()) : null;
+      LocatedBlock lastBlock = res.hasBlock() ? PBHelper
+          .convert(res.getBlock()) : null;
+      HdfsFileStatus stat = (res.hasStat()) ? PBHelper.convert(res.getStat())
+          : null;
+      return new LastBlockWithStatus(lastBlock, stat);
     } catch (ServiceException e) {
       throw ProtobufHelper.getRemoteException(e);
     }

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

@@ -38,6 +38,7 @@ import org.apache.hadoop.hdfs.protocol.Block;
 import org.apache.hadoop.hdfs.protocol.CacheDirectiveInfo;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants;
 import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
+import org.apache.hadoop.hdfs.protocol.LastBlockWithStatus;
 import org.apache.hadoop.hdfs.protocol.LayoutVersion;
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
 import org.apache.hadoop.hdfs.server.blockmanagement.BlockInfo;
@@ -392,8 +393,12 @@ public class FSEditLogLoader {
           
           // add the op into retry cache is necessary
           if (toAddRetryCache) {
+            HdfsFileStatus stat = fsNamesys.dir.createFileStatus(
+                HdfsFileStatus.EMPTY_NAME, newFile,
+                BlockStoragePolicySuite.ID_UNSPECIFIED,
+                Snapshot.CURRENT_STATE_ID, false, iip);
             fsNamesys.addCacheEntryWithPayload(addCloseOp.rpcClientId,
-                addCloseOp.rpcCallId, lb);
+                addCloseOp.rpcCallId, new LastBlockWithStatus(lb, stat));
           }
         }
       }

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

@@ -185,6 +185,7 @@ import org.apache.hadoop.hdfs.protocol.DirectoryListing;
 import org.apache.hadoop.hdfs.protocol.EncryptionZone;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants;
+import org.apache.hadoop.hdfs.protocol.LastBlockWithStatus;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants.DatanodeReportType;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants.SafeModeAction;
 import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
@@ -2888,7 +2889,7 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
   /**
    * Append to an existing file in the namespace.
    */
-  LocatedBlock appendFile(
+  LastBlockWithStatus appendFile(
       String src, String holder, String clientMachine, boolean logRetryCache)
       throws IOException {
     try {
@@ -2899,7 +2900,7 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
     }
   }
 
-  private LocatedBlock appendFileInt(final String srcArg, String holder,
+  private LastBlockWithStatus appendFileInt(final String srcArg, String holder,
       String clientMachine, boolean logRetryCache)
       throws AccessControlException, SafeModeException,
       FileAlreadyExistsException, FileNotFoundException,
@@ -2912,6 +2913,7 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
     }
     boolean skipSync = false;
     LocatedBlock lb = null;
+    HdfsFileStatus stat = null;
     FSPermissionChecker pc = getPermissionChecker();
     checkOperation(OperationCategory.WRITE);
     byte[][] pathComponents = FSDirectory.getPathComponentsForReservedPath(src);
@@ -2921,6 +2923,8 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
       checkNameNodeSafeMode("Cannot append to file" + src);
       src = dir.resolvePath(pc, src, pathComponents);
       lb = appendFileInternal(pc, src, holder, clientMachine, logRetryCache);
+      stat = dir.getFileInfo(src, false, FSDirectory.isReservedRawName(srcArg),
+          true);
     } catch (StandbyException se) {
       skipSync = true;
       throw se;
@@ -2941,7 +2945,7 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
       }
     }
     logAuditEvent(true, "append", srcArg);
-    return lb;
+    return new LastBlockWithStatus(lb, stat);
   }
 
   ExtendedBlock getExtendedBlock(Block blk) {

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

@@ -35,6 +35,7 @@ import java.util.List;
 import java.util.Set;
 
 import com.google.common.collect.Lists;
+
 import org.apache.commons.logging.Log;
 import org.apache.hadoop.HadoopIllegalArgumentException;
 import org.apache.hadoop.conf.Configuration;
@@ -86,6 +87,7 @@ import org.apache.hadoop.hdfs.protocol.EncryptionZone;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.protocol.FSLimitException;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants;
+import org.apache.hadoop.hdfs.protocol.LastBlockWithStatus;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants.DatanodeReportType;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants.RollingUpgradeAction;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants.SafeModeAction;
@@ -618,7 +620,7 @@ class NameNodeRpcServer implements NamenodeProtocols {
   }
 
   @Override // ClientProtocol
-  public LocatedBlock append(String src, String clientName) 
+  public LastBlockWithStatus append(String src, String clientName) 
       throws IOException {
     String clientMachine = getClientMachine();
     if (stateChangeLog.isDebugEnabled()) {
@@ -627,10 +629,10 @@ class NameNodeRpcServer implements NamenodeProtocols {
     }
     CacheEntryWithPayload cacheEntry = RetryCache.waitForCompletion(retryCache, null);
     if (cacheEntry != null && cacheEntry.isSuccess()) {
-      return (LocatedBlock) cacheEntry.getPayload();
+      return (LastBlockWithStatus) cacheEntry.getPayload();
     }
 
-    LocatedBlock info = null;
+    LastBlockWithStatus info = null;
     boolean success = false;
     try {
       info = namesystem.appendFile(src, clientName, clientMachine,

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

@@ -90,6 +90,7 @@ message AppendRequestProto {
 
 message AppendResponseProto {
   optional LocatedBlockProto block = 1;
+  optional HdfsFileStatusProto stat = 2;
 }
 
 message SetReplicationRequestProto {

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestNamenodeRetryCache.java

@@ -45,7 +45,7 @@ import org.apache.hadoop.hdfs.MiniDFSNNTopology;
 import org.apache.hadoop.hdfs.protocol.DatanodeID;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
-import org.apache.hadoop.hdfs.protocol.LocatedBlock;
+import org.apache.hadoop.hdfs.protocol.LastBlockWithStatus;
 import org.apache.hadoop.hdfs.server.protocol.NamenodeProtocols;
 import org.apache.hadoop.io.EnumSetWritable;
 import org.apache.hadoop.ipc.ClientId;
@@ -232,7 +232,7 @@ public class TestNamenodeRetryCache {
     
     // Retried append requests succeed
     newCall();
-    LocatedBlock b = nnRpc.append(src, "holder");
+    LastBlockWithStatus b = nnRpc.append(src, "holder");
     Assert.assertEquals(b, nnRpc.append(src, "holder"));
     Assert.assertEquals(b, nnRpc.append(src, "holder"));
     

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/ha/TestRetryCacheWithHA.java

@@ -66,6 +66,7 @@ import org.apache.hadoop.hdfs.protocol.ClientProtocol;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
+import org.apache.hadoop.hdfs.protocol.LastBlockWithStatus;
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
 import org.apache.hadoop.hdfs.protocol.LocatedBlocks;
 import org.apache.hadoop.hdfs.protocol.CacheDirectiveEntry;
@@ -420,7 +421,7 @@ public class TestRetryCacheWithHA {
   /** append operation */
   class AppendOp extends AtMostOnceOp {
     private final String fileName;
-    private LocatedBlock lbk;
+    private LastBlockWithStatus lbk;
     
     AppendOp(DFSClient client, String fileName) {
       super("append", client);