svn merge -c -1430507 . for reverting HDFS-4353. Encapsulate connections to peers in Peer and PeerServer classes

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1430662 13f79535-47bb-0310-9956-ffa450edef68

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/net/SocketInputStream.java

@@ -19,7 +19,6 @@
 package org.apache.hadoop.net;
 
 import java.io.IOException;
-import org.apache.hadoop.classification.InterfaceAudience;
 import java.io.InputStream;
 import java.net.Socket;
 import java.net.SocketTimeoutException;
@@ -38,8 +37,7 @@ import java.nio.channels.SelectionKey;
  * IllegalBlockingModeException. 
  * Please use {@link SocketOutputStream} for writing.
  */
-@InterfaceAudience.LimitedPrivate("HDFS")
-public class SocketInputStream extends InputStream
+class SocketInputStream extends InputStream
                                implements ReadableByteChannel {
 
   private Reader reader;

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/net/SocketOutputStream.java

@@ -260,8 +260,4 @@ public class SocketOutputStream extends OutputStream
       throws IOException {
     transferToFully(fileCh, position, count, null, null);
   }
-
-  public void setTimeout(int timeoutMs) {
-    writer.setTimeout(timeoutMs);
-  }
 }

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

@@ -180,9 +180,6 @@ Trunk (Unreleased)
     HDFS-4352. Encapsulate arguments to BlockReaderFactory in a class
     (Colin Patrick McCabe via todd)
 
-    HDFS-4353. Encapsulate connections to peers in Peer and PeerServer classes
-    (Colin Patrick McCabe via todd)
-
   OPTIMIZATIONS
 
   BUG FIXES

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

@@ -18,8 +18,10 @@
 package org.apache.hadoop.hdfs;
 
 import java.io.IOException;
+import java.net.Socket;
 
 import org.apache.hadoop.fs.ByteBufferReadable;
+import org.apache.hadoop.hdfs.protocol.datatransfer.IOStreamPair;
 
 /**
  * A BlockReader is responsible for reading a single block
@@ -41,18 +43,7 @@ public interface BlockReader extends ByteBufferReadable {
    */
   long skip(long n) throws IOException;
 
-  /**
-   * Close the block reader.
-   *
-   * @param peerCache      The PeerCache to put the Peer we're using back
-   *                       into, or null if we should simply close the Peer
-   *                       we're using (along with its Socket).
-   *                       Some block readers, like BlockReaderLocal, may
-   *                       not make use of this parameter.
-   *
-   * @throws IOException
-   */
-  void close(PeerCache peerCache) throws IOException;
+  void close() throws IOException;
 
   /**
    * Read exactly the given amount of data, throwing an exception
@@ -69,4 +60,20 @@ public interface BlockReader extends ByteBufferReadable {
    * filled or the next call will return EOF.
    */
   int readAll(byte[] buf, int offset, int len) throws IOException;
+
+  /**
+   * Take the socket used to talk to the DN.
+   */
+  Socket takeSocket();
+
+  /**
+   * Whether the BlockReader has reached the end of its input stream
+   * and successfully sent a status code back to the datanode.
+   */
+  boolean hasSentStatusCode();
+
+  /**
+   * @return a reference to the streams this block reader is using.
+   */
+  IOStreamPair getStreams();
 }

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

@@ -19,18 +19,19 @@ package org.apache.hadoop.hdfs;
 
 import java.io.IOException;
 import java.net.InetSocketAddress;
+import java.net.Socket;
 
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.hdfs.DFSClient.Conf;
-import org.apache.hadoop.hdfs.net.Peer;
-import org.apache.hadoop.hdfs.protocol.DatanodeID;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
+import org.apache.hadoop.hdfs.protocol.datatransfer.DataTransferEncryptor;
+import org.apache.hadoop.hdfs.protocol.datatransfer.IOStreamPair;
+import org.apache.hadoop.hdfs.security.token.block.DataEncryptionKey;
 import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
 import org.apache.hadoop.hdfs.server.common.HdfsServerConstants;
+import org.apache.hadoop.net.NetUtils;
 import org.apache.hadoop.security.token.Token;
 
-import com.google.common.base.Preconditions;
-
 
 /** 
  * Utility class to create BlockReader implementations.
@@ -46,73 +47,18 @@ public class BlockReaderFactory {
   @InterfaceAudience.Private
   public static class Params {
     private final Conf conf;
-    /**
-     * The peer that this BlockReader will be connected to.
-     * You must set this.
-     */
-    private Peer peer = null;
-    
-    /**
-     * The file name that this BlockReader pertains to.
-     * This is optional and only used for display and logging purposes.
-     */
+    private Socket socket = null;
     private String file = null;
-
-    /**
-     * The block that this BlockReader is reading.
-     * You must set this.
-     */
     private ExtendedBlock block = null;
-    
-    /**
-     * The BlockTokenIdentifier to use, or null to use none.
-     */
     private Token<BlockTokenIdentifier> blockToken = null;
-
-    /**
-     * The offset in the block to start reading at.
-     */
     private long startOffset = 0;
-    
-    /**
-     * The total number of bytes we might want to read, or -1 to assume no
-     * limit.
-     */
     private long len = -1;
-    
-    /**
-     * The buffer size to use.
-     *
-     * If this is not set, we will use the default from the Conf.
-     */
     private int bufferSize;
-    
-    /**
-     * Whether or not we should verify the checksum.
-     *
-     * This is used instead of conf.verifyChecksum, because there are some
-     * cases when we may want to explicitly turn off checksum verification,
-     * such as when the caller has explicitly asked for a file to be opened
-     * without checksum verification.
-     */
     private boolean verifyChecksum = true;
-
-    /**
-     * Whether or not we should try to use short circuit local reads.
-     */
     private boolean shortCircuitLocalReads = false;
-
-    /**
-     * The name of the client using this BlockReader, for logging and
-     * debugging purposes.
-     */
     private String clientName = "";
-    
-    /**
-     * The DataNode on which this Block resides.
-     * You must set this.
-     */
-    private DatanodeID datanodeID = null;
+    private DataEncryptionKey encryptionKey = null;
+    private IOStreamPair ioStreamPair = null;
 
     public Params(Conf conf) {
       this.conf = conf;
@@ -121,11 +67,11 @@ public class BlockReaderFactory {
     public Conf getConf() {
       return conf;
     }
-    public Peer getPeer() {
-      return peer;
+    public Socket getSocket() {
+      return socket;
     }
-    public Params setPeer(Peer peer) {
-      this.peer = peer;
+    public Params setSocket(Socket socket) {
+      this.socket = socket;
       return this;
     }
     public String getFile() {
@@ -191,12 +137,19 @@ public class BlockReaderFactory {
       this.clientName = clientName;
       return this;
     }
-    public Params setDatanodeID(DatanodeID datanodeID) {
-      this.datanodeID = datanodeID;
+    public Params setEncryptionKey(DataEncryptionKey encryptionKey) {
+      this.encryptionKey = encryptionKey;
       return this;
     }
-    public DatanodeID getDatanodeID() {
-      return datanodeID;
+    public DataEncryptionKey getEncryptionKey() {
+      return encryptionKey;
+    }
+    public IOStreamPair getIoStreamPair() {
+      return ioStreamPair;
+    }
+    public Params setIoStreamPair(IOStreamPair ioStreamPair) {
+      this.ioStreamPair = ioStreamPair;
+      return this;
     }
   }
 
@@ -211,27 +164,24 @@ public class BlockReaderFactory {
    */
   @SuppressWarnings("deprecation")
   public static BlockReader newBlockReader(Params params) throws IOException {
-    Preconditions.checkNotNull(params.getPeer());
-    Preconditions.checkNotNull(params.getBlock());
-    Preconditions.checkNotNull(params.getDatanodeID());
-    // First, let's set the read and write timeouts appropriately.
-    // This will keep us from blocking forever if something goes wrong during
-    // network communication.
-    Peer peer = params.getPeer();
-    peer.setReadTimeout(params.getConf().socketTimeout);
-    peer.setWriteTimeout(HdfsServerConstants.WRITE_TIMEOUT);
-
     if (params.getConf().useLegacyBlockReader) {
-      // The legacy BlockReader doesn't require that the Peers it uses
-      // have associated ReadableByteChannels.  This makes it easier to use 
-      // with some older Socket classes like, say, SocksSocketImpl.
-      //
-      // TODO: create a wrapper class that makes channel-less sockets look like
-      // they have a channel, so that we can finally remove the legacy
-      // RemoteBlockReader.  See HDFS-2534.
+      if (params.getEncryptionKey() != null) {
+        throw new RuntimeException("Encryption is not supported with the legacy block reader.");
+      }
       return RemoteBlockReader.newBlockReader(params);
     } else {
-      // The usual block reader.
+      Socket sock = params.getSocket();
+      if (params.getIoStreamPair() == null) {
+        params.setIoStreamPair(new IOStreamPair(NetUtils.getInputStream(sock),
+            NetUtils.getOutputStream(sock, HdfsServerConstants.WRITE_TIMEOUT)));
+        if (params.getEncryptionKey() != null) {
+          IOStreamPair encryptedStreams =
+              DataTransferEncryptor.getEncryptedStreams(
+                  params.getIoStreamPair().out, params.getIoStreamPair().in, 
+                  params.getEncryptionKey());
+          params.setIoStreamPair(encryptedStreams);
+        }
+      }
       return RemoteBlockReader2.newBlockReader(params);
     }
   }
@@ -247,4 +197,4 @@ public class BlockReaderFactory {
       final String poolId, final long blockId) {
     return s.toString() + ":" + poolId + ":" + blockId;
   }
-}
+}

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

@@ -649,7 +649,7 @@ class BlockReaderLocal implements BlockReader {
   }
 
   @Override
-  public synchronized void close(PeerCache peerCache) throws IOException {
+  public synchronized void close() throws IOException {
     dataIn.close();
     if (checksumIn != null) {
       checksumIn.close();
@@ -675,4 +675,19 @@ class BlockReaderLocal implements BlockReader {
   public void readFully(byte[] buf, int off, int len) throws IOException {
     BlockReaderUtil.readFully(this, buf, off, len);
   }
+
+  @Override
+  public Socket takeSocket() {
+    return null;
+  }
+
+  @Override
+  public boolean hasSentStatusCode() {
+    return false;
+  }
+
+  @Override
+  public IOStreamPair getStreams() {
+    return null;
+  }
 }

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

@@ -191,7 +191,7 @@ public class DFSClient implements java.io.Closeable {
   final FileSystem.Statistics stats;
   final int hdfsTimeout;    // timeout value for a DFS operation.
   private final String authority;
-  final PeerCache peerCache;
+  final SocketCache socketCache;
   final Conf dfsClientConf;
   private Random r = new Random();
   private SocketAddress[] localInterfaceAddrs;
@@ -433,7 +433,7 @@ public class DFSClient implements java.io.Closeable {
       Joiner.on(',').join(localInterfaceAddrs) + "]");
     }
     
-    this.peerCache = PeerCache.getInstance(dfsClientConf.socketCacheCapacity, dfsClientConf.socketCacheExpiry);
+    this.socketCache = SocketCache.getInstance(dfsClientConf.socketCacheCapacity, dfsClientConf.socketCacheExpiry);
   }
 
   /**

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

@@ -32,15 +32,12 @@ import java.util.Map.Entry;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 
-import org.apache.commons.io.IOUtils;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.fs.ChecksumException;
 import org.apache.hadoop.fs.ByteBufferReadable;
 import org.apache.hadoop.fs.FSInputStream;
 import org.apache.hadoop.fs.UnresolvedLinkException;
-import org.apache.hadoop.hdfs.net.EncryptedPeer;
-import org.apache.hadoop.hdfs.net.Peer;
-import org.apache.hadoop.hdfs.net.TcpPeerServer;
+import org.apache.hadoop.hdfs.SocketCache.SocketAndStreams;
 import org.apache.hadoop.hdfs.protocol.ClientDatanodeProtocol;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
@@ -49,7 +46,6 @@ import org.apache.hadoop.hdfs.protocol.LocatedBlocks;
 import org.apache.hadoop.hdfs.protocol.datatransfer.IOStreamPair;
 import org.apache.hadoop.hdfs.protocol.datatransfer.InvalidEncryptionKeyException;
 import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
-import org.apache.hadoop.hdfs.security.token.block.DataEncryptionKey;
 import org.apache.hadoop.hdfs.security.token.block.InvalidBlockTokenException;
 import org.apache.hadoop.hdfs.server.datanode.ReplicaNotFoundException;
 import org.apache.hadoop.ipc.RPC;
@@ -64,7 +60,7 @@ import org.apache.hadoop.security.token.Token;
  ****************************************************************/
 @InterfaceAudience.Private
 public class DFSInputStream extends FSInputStream implements ByteBufferReadable {
-  private final PeerCache peerCache;
+  private final SocketCache socketCache;
 
   private final DFSClient dfsClient;
   private boolean closed = false;
@@ -114,7 +110,7 @@ public class DFSInputStream extends FSInputStream implements ByteBufferReadable
     this.verifyChecksum = verifyChecksum;
     this.buffersize = buffersize;
     this.src = src;
-    this.peerCache = dfsClient.peerCache;
+    this.socketCache = dfsClient.socketCache;
     prefetchSize = dfsClient.getConf().prefetchSize;
     timeWindow = dfsClient.getConf().timeWindow;
     nCachedConnRetry = dfsClient.getConf().nCachedConnRetry;
@@ -428,7 +424,7 @@ public class DFSInputStream extends FSInputStream implements ByteBufferReadable
 
     // Will be getting a new BlockReader.
     if (blockReader != null) {
-      blockReader.close(peerCache);
+      closeBlockReader(blockReader);
       blockReader = null;
     }
 
@@ -510,7 +506,7 @@ public class DFSInputStream extends FSInputStream implements ByteBufferReadable
     dfsClient.checkOpen();
 
     if (blockReader != null) {
-      blockReader.close(peerCache);
+      closeBlockReader(blockReader);
       blockReader = null;
     }
     super.close();
@@ -837,7 +833,7 @@ public class DFSInputStream extends FSInputStream implements ByteBufferReadable
         }
       } finally {
         if (reader != null) {
-          reader.close(peerCache);
+          closeBlockReader(reader);
         }
       }
       // Put chosen node into dead list, continue
@@ -845,30 +841,16 @@ public class DFSInputStream extends FSInputStream implements ByteBufferReadable
     }
   }
 
-  private Peer newPeer(InetSocketAddress addr) throws IOException {
-    Peer peer = null;
-    boolean success = false;
-    Socket sock = null;
-    try {
-      sock = dfsClient.socketFactory.createSocket();
-      NetUtils.connect(sock, addr,
-        dfsClient.getRandomLocalInterfaceAddr(),
-        dfsClient.getConf().socketTimeout);
-      peer = TcpPeerServer.peerFromSocket(sock);
-      
-      // Add encryption if configured.
-      DataEncryptionKey key = dfsClient.getDataEncryptionKey();
-      if (key != null) {
-        peer = new EncryptedPeer(peer, key);
-      }
-      success = true;
-      return peer;
-    } finally {
-      if (!success) {
-        IOUtils.closeQuietly(peer);
-        IOUtils.closeQuietly(sock);
-      }
+  /**
+   * Close the given BlockReader and cache its socket.
+   */
+  private void closeBlockReader(BlockReader reader) throws IOException {
+    if (reader.hasSentStatusCode()) {
+      IOStreamPair ioStreams = reader.getStreams();
+      Socket oldSock = reader.takeSocket();
+      socketCache.put(oldSock, ioStreams);
     }
+    reader.close();
   }
 
   /**
@@ -914,16 +896,40 @@ public class DFSInputStream extends FSInputStream implements ByteBufferReadable
     // Allow retry since there is no way of knowing whether the cached socket
     // is good until we actually use it.
     for (int retries = 0; retries <= nCachedConnRetry && fromCache; ++retries) {
-      Peer peer = null;
+      SocketAndStreams sockAndStreams = null;
       // Don't use the cache on the last attempt - it's possible that there
       // are arbitrarily many unusable sockets in the cache, but we don't
       // want to fail the read.
       if (retries < nCachedConnRetry) {
-        peer = peerCache.get(chosenNode);
+        sockAndStreams = socketCache.get(dnAddr);
       }
-      if (peer == null) {
-        peer = newPeer(dnAddr);
+      Socket sock;
+      if (sockAndStreams == null) {
         fromCache = false;
+
+        sock = dfsClient.socketFactory.createSocket();
+        
+        // TCP_NODELAY is crucial here because of bad interactions between
+        // Nagle's Algorithm and Delayed ACKs. With connection keepalive
+        // between the client and DN, the conversation looks like:
+        //   1. Client -> DN: Read block X
+        //   2. DN -> Client: data for block X
+        //   3. Client -> DN: Status OK (successful read)
+        //   4. Client -> DN: Read block Y
+        // The fact that step #3 and #4 are both in the client->DN direction
+        // triggers Nagling. If the DN is using delayed ACKs, this results
+        // in a delay of 40ms or more.
+        //
+        // TCP_NODELAY disables nagling and thus avoids this performance
+        // disaster.
+        sock.setTcpNoDelay(true);
+
+        NetUtils.connect(sock, dnAddr,
+            dfsClient.getRandomLocalInterfaceAddr(),
+            dfsClient.getConf().socketTimeout);
+        sock.setSoTimeout(dfsClient.getConf().socketTimeout);
+      } else {
+        sock = sockAndStreams.sock;
       }
 
       try {
@@ -933,13 +939,19 @@ public class DFSInputStream extends FSInputStream implements ByteBufferReadable
                 setFile(file).setBlock(block).setBlockToken(blockToken).
                 setStartOffset(startOffset).setLen(len).
                 setBufferSize(bufferSize).setVerifyChecksum(verifyChecksum).
-                setClientName(clientName).setDatanodeID(chosenNode).
-                setPeer(peer));
+                setClientName(clientName).
+                setEncryptionKey(dfsClient.getDataEncryptionKey()).
+                setIoStreamPair(sockAndStreams == null ? null : sockAndStreams.ioStreams).
+                setSocket(sock));
         return reader;
       } catch (IOException ex) {
         // Our socket is no good.
-        DFSClient.LOG.debug("Error making BlockReader. Closing stale " + peer, ex);
-        IOUtils.closeQuietly(peer);
+        DFSClient.LOG.debug("Error making BlockReader. Closing stale " + sock, ex);
+        if (sockAndStreams != null) {
+          sockAndStreams.close();
+        } else {
+          sock.close();
+        }
         err = ex;
       }
     }

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

@@ -25,20 +25,25 @@ import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.IOException;
 import java.net.InetSocketAddress;
+import java.net.Socket;
 import java.nio.ByteBuffer;
 
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.fs.FSInputChecker;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hdfs.net.Peer;
-import org.apache.hadoop.hdfs.protocol.DatanodeID;
+import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.protocol.datatransfer.DataTransferProtoUtil;
+import org.apache.hadoop.hdfs.protocol.datatransfer.IOStreamPair;
 import org.apache.hadoop.hdfs.protocol.datatransfer.PacketHeader;
 import org.apache.hadoop.hdfs.protocol.datatransfer.Sender;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.BlockOpResponseProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ReadOpChecksumInfoProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.Status;
+import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
+import org.apache.hadoop.hdfs.server.common.HdfsServerConstants;
 import org.apache.hadoop.io.IOUtils;
+import org.apache.hadoop.net.NetUtils;
+import org.apache.hadoop.security.token.Token;
 import org.apache.hadoop.util.DataChecksum;
 
 
@@ -51,8 +56,7 @@ import org.apache.hadoop.util.DataChecksum;
 @Deprecated
 public class RemoteBlockReader extends FSInputChecker implements BlockReader {
 
-  private final Peer peer;
-  private final DatanodeID datanodeID;
+  Socket dnSock; //for now just sending the status code (e.g. checksumOk) after the read.
   private final DataInputStream in;
   private DataChecksum checksum;
 
@@ -122,9 +126,9 @@ public class RemoteBlockReader extends FSInputChecker implements BlockReader {
     // if eos was set in the previous read, send a status code to the DN
     if (eos && !eosBefore && nRead >= 0) {
       if (needChecksum()) {
-        sendReadResult(peer, Status.CHECKSUM_OK);
+        sendReadResult(dnSock, Status.CHECKSUM_OK);
       } else {
-        sendReadResult(peer, Status.SUCCESS);
+        sendReadResult(dnSock, Status.SUCCESS);
       }
     }
     return nRead;
@@ -318,8 +322,7 @@ public class RemoteBlockReader extends FSInputChecker implements BlockReader {
   
   private RemoteBlockReader(String file, String bpid, long blockId,
       DataInputStream in, DataChecksum checksum, boolean verifyChecksum,
-      long startOffset, long firstChunkOffset, long bytesToRead, 
-      Peer peer, DatanodeID datanodeID) {
+      long startOffset, long firstChunkOffset, long bytesToRead, Socket dnSock) {
     // Path is used only for printing block and file information in debug
     super(new Path("/blk_" + blockId + ":" + bpid + ":of:"+ file)/*too non path-like?*/,
           1, verifyChecksum,
@@ -327,8 +330,7 @@ public class RemoteBlockReader extends FSInputChecker implements BlockReader {
           checksum.getBytesPerChecksum(),
           checksum.getChecksumSize());
     
-    this.peer = peer;
-    this.datanodeID = datanodeID;
+    this.dnSock = dnSock;
     this.in = in;
     this.checksum = checksum;
     this.startOffset = Math.max( startOffset, 0 );
@@ -365,8 +367,9 @@ public class RemoteBlockReader extends FSInputChecker implements BlockReader {
   public static RemoteBlockReader newBlockReader(BlockReaderFactory.Params params)
         throws IOException {
     // in and out will be closed when sock is closed (by the caller)
+    Socket sock = params.getSocket();
     final DataOutputStream out = new DataOutputStream(new BufferedOutputStream(
-        params.getPeer().getOutputStream()));
+          NetUtils.getOutputStream(sock, HdfsServerConstants.WRITE_TIMEOUT)));
     new Sender(out).readBlock(params.getBlock(), params.getBlockToken(), 
         params.getClientName(), params.getStartOffset(), params.getLen());
 
@@ -374,13 +377,13 @@ public class RemoteBlockReader extends FSInputChecker implements BlockReader {
     // Get bytes in block, set streams
     //
     DataInputStream in = new DataInputStream(
-        new BufferedInputStream(params.getPeer().getInputStream(),
+        new BufferedInputStream(NetUtils.getInputStream(sock), 
             params.getBufferSize()));
 
     BlockOpResponseProto status = BlockOpResponseProto.parseFrom(
         vintPrefixed(in));
-    RemoteBlockReader2.checkSuccess(status, params.getPeer(),
-        params.getBlock(), params.getFile());
+    RemoteBlockReader2.checkSuccess(status, sock, params.getBlock(),
+        params.getFile());
     ReadOpChecksumInfoProto checksumInfo =
       status.getReadOpChecksumInfo();
     DataChecksum checksum = DataTransferProtoUtil.fromProto(
@@ -399,20 +402,18 @@ public class RemoteBlockReader extends FSInputChecker implements BlockReader {
 
     return new RemoteBlockReader(params.getFile(), params.getBlock().getBlockPoolId(), 
         params.getBlock().getBlockId(), in, checksum, params.getVerifyChecksum(),
-        params.getStartOffset(), firstChunkOffset, params.getLen(),
-        params.getPeer(), params.getDatanodeID());
+        params.getStartOffset(), firstChunkOffset, params.getLen(), sock);
   }
 
   @Override
-  public synchronized void close(PeerCache peerCache) throws IOException {
+  public synchronized void close() throws IOException {
     startOffset = -1;
     checksum = null;
-    if (peerCache != null && sentStatusCode) {
-      peerCache.put(datanodeID, peer);
-    } else {
-      peer.close();
+    if (dnSock != null) {
+      dnSock.close();
     }
-    // in will be closed when its Peer is closed.
+
+    // in will be closed when its Socket is closed.
   }
   
   @Override
@@ -426,21 +427,37 @@ public class RemoteBlockReader extends FSInputChecker implements BlockReader {
     return readFully(this, buf, offset, len);
   }
 
+  @Override
+  public Socket takeSocket() {
+    assert hasSentStatusCode() :
+      "BlockReader shouldn't give back sockets mid-read";
+    Socket res = dnSock;
+    dnSock = null;
+    return res;
+  }
+
+  @Override
+  public boolean hasSentStatusCode() {
+    return sentStatusCode;
+  }
+
   /**
    * When the reader reaches end of the read, it sends a status response
    * (e.g. CHECKSUM_OK) to the DN. Failure to do so could lead to the DN
    * closing our connection (which we will re-open), but won't affect
    * data correctness.
    */
-  void sendReadResult(Peer peer, Status statusCode) {
-    assert !sentStatusCode : "already sent status code to " + peer;
+  void sendReadResult(Socket sock, Status statusCode) {
+    assert !sentStatusCode : "already sent status code to " + sock;
     try {
-      RemoteBlockReader2.writeReadResult(peer.getOutputStream(), statusCode);
+      RemoteBlockReader2.writeReadResult(
+          NetUtils.getOutputStream(sock, HdfsServerConstants.WRITE_TIMEOUT),
+          statusCode);
       sentStatusCode = true;
     } catch (IOException e) {
       // It's ok not to be able to send this. But something is probably wrong.
       LOG.info("Could not send read status (" + statusCode + ") to datanode " +
-               datanodeID + ": " + e.getMessage());
+               sock.getInetAddress() + ": " + e.getMessage());
     }
   }
   
@@ -460,4 +477,12 @@ public class RemoteBlockReader extends FSInputChecker implements BlockReader {
   public int read(ByteBuffer buf) throws IOException {
     throw new UnsupportedOperationException("readDirect unsupported in RemoteBlockReader");
   }
+
+  @Override
+  public IOStreamPair getStreams() {
+    // This class doesn't support encryption, which is the only thing this
+    // method is used for. See HDFS-3637.
+    return null;
+  }
+
 }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/RemoteBlockReader2.java

@@ -25,15 +25,16 @@ import java.io.DataOutputStream;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.net.InetSocketAddress;
+import java.net.Socket;
 import java.nio.ByteBuffer;
+import java.nio.channels.ReadableByteChannel;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.classification.InterfaceAudience;
-import org.apache.hadoop.hdfs.protocol.DatanodeID;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.protocol.datatransfer.DataTransferProtoUtil;
-import org.apache.hadoop.hdfs.net.Peer;
+import org.apache.hadoop.hdfs.protocol.datatransfer.IOStreamPair;
 import org.apache.hadoop.hdfs.protocol.datatransfer.PacketHeader;
 import org.apache.hadoop.hdfs.protocol.datatransfer.PacketReceiver;
 import org.apache.hadoop.hdfs.protocol.datatransfer.Sender;
@@ -41,11 +42,13 @@ import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.BlockOpResponseP
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ClientReadStatusProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ReadOpChecksumInfoProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.Status;
+import org.apache.hadoop.hdfs.security.token.block.DataEncryptionKey;
+import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
 import org.apache.hadoop.hdfs.security.token.block.InvalidBlockTokenException;
+import org.apache.hadoop.net.SocketInputWrapper;
+import org.apache.hadoop.security.token.Token;
 import org.apache.hadoop.util.DataChecksum;
 
-import com.google.common.annotations.VisibleForTesting;
-
 /**
  * This is a wrapper around connection to datanode
  * and understands checksum, offset etc.
@@ -76,8 +79,11 @@ import com.google.common.annotations.VisibleForTesting;
 public class RemoteBlockReader2  implements BlockReader {
 
   static final Log LOG = LogFactory.getLog(RemoteBlockReader2.class);
-  private final DatanodeID datanodeID;
-  private final Peer peer;
+  
+  Socket dnSock;
+  // for now just sending the status code (e.g. checksumOk) after the read.
+  private IOStreamPair ioStreams;
+  private final ReadableByteChannel in;
   private DataChecksum checksum;
   
   private PacketReceiver packetReceiver = new PacketReceiver(true);
@@ -109,11 +115,6 @@ public class RemoteBlockReader2  implements BlockReader {
   /** Amount of unread data in the current received packet */
   int dataLeft = 0;
   
-  @VisibleForTesting
-  public Peer getPeer() {
-    return peer;
-  }
-  
   @Override
   public synchronized int read(byte[] buf, int off, int len) 
                                throws IOException {
@@ -154,7 +155,7 @@ public class RemoteBlockReader2  implements BlockReader {
 
   private void readNextPacket() throws IOException {
     //Read packet headers.
-    packetReceiver.receiveNextPacket(peer.getInputStreamChannel());
+    packetReceiver.receiveNextPacket(in);
 
     PacketHeader curHeader = packetReceiver.getHeader();
     curDataSlice = packetReceiver.getDataSlice();
@@ -235,7 +236,7 @@ public class RemoteBlockReader2  implements BlockReader {
       LOG.trace("Reading empty packet at end of read");
     }
     
-    packetReceiver.receiveNextPacket(peer.getInputStreamChannel());
+    packetReceiver.receiveNextPacket(in);
 
     PacketHeader trailer = packetReceiver.getHeader();
     if (!trailer.isLastPacketInBlock() ||
@@ -246,10 +247,11 @@ public class RemoteBlockReader2  implements BlockReader {
   }
 
   protected RemoteBlockReader2(BlockReaderFactory.Params params, 
-      DataChecksum checksum, long firstChunkOffset) {
+      DataChecksum checksum, long firstChunkOffset, ReadableByteChannel in) {
     // Path is used only for printing block and file information in debug
-    this.datanodeID = params.getDatanodeID();
-    this.peer = params.getPeer();
+    this.dnSock = params.getSocket();
+    this.ioStreams = params.getIoStreamPair();
+    this.in = in;
     this.checksum = checksum;
     this.verifyChecksum = params.getVerifyChecksum();
     this.startOffset = Math.max( params.getStartOffset(), 0 );
@@ -266,19 +268,38 @@ public class RemoteBlockReader2  implements BlockReader {
 
 
   @Override
-  public synchronized void close(PeerCache peerCache) throws IOException {
+  public synchronized void close() throws IOException {
     packetReceiver.close();
     
     startOffset = -1;
     checksum = null;
-    if (peerCache != null && sentStatusCode) {
-      peerCache.put(datanodeID, peer);
-    } else {
-      peer.close();
+    if (dnSock != null) {
+      dnSock.close();
     }
 
     // in will be closed when its Socket is closed.
   }
+  
+  /**
+   * Take the socket used to talk to the DN.
+   */
+  @Override
+  public Socket takeSocket() {
+    assert hasSentStatusCode() :
+      "BlockReader shouldn't give back sockets mid-read";
+    Socket res = dnSock;
+    dnSock = null;
+    return res;
+  }
+
+  /**
+   * Whether the BlockReader has reached the end of its input stream
+   * and successfully sent a status code back to the datanode.
+   */
+  @Override
+  public boolean hasSentStatusCode() {
+    return sentStatusCode;
+  }
 
   /**
    * When the reader reaches end of the read, it sends a status response
@@ -287,14 +308,14 @@ public class RemoteBlockReader2  implements BlockReader {
    * data correctness.
    */
   void sendReadResult(Status statusCode) {
-    assert !sentStatusCode : "already sent status code to " + peer;
+    assert !sentStatusCode : "already sent status code to " + dnSock;
     try {
-      writeReadResult(peer.getOutputStream(), statusCode);
+      writeReadResult(ioStreams.out, statusCode);
       sentStatusCode = true;
     } catch (IOException e) {
       // It's ok not to be able to send this. But something is probably wrong.
       LOG.info("Could not send read status (" + statusCode + ") to datanode " +
-               peer.getRemoteAddressString() + ": " + e.getMessage());
+               dnSock.getInetAddress() + ": " + e.getMessage());
     }
   }
 
@@ -352,20 +373,29 @@ public class RemoteBlockReader2  implements BlockReader {
    */
   public static BlockReader newBlockReader(BlockReaderFactory.Params params)
                                      throws IOException {
+    IOStreamPair ioStreams = params.getIoStreamPair();
+    ReadableByteChannel ch;
+    if (ioStreams.in instanceof SocketInputWrapper) {
+      ch = ((SocketInputWrapper)ioStreams.in).getReadableByteChannel();
+    } else {
+      ch = (ReadableByteChannel) ioStreams.in;
+    }
+    
     // in and out will be closed when sock is closed (by the caller)
     final DataOutputStream out = new DataOutputStream(new BufferedOutputStream(
-          params.getPeer().getOutputStream()));
+          ioStreams.out));
     new Sender(out).readBlock(params.getBlock(), params.getBlockToken(), 
         params.getClientName(), params.getStartOffset(), params.getLen());
 
     //
     // Get bytes in block
     //
-    DataInputStream in = new DataInputStream(params.getPeer().getInputStream());
+    DataInputStream in = new DataInputStream(ioStreams.in);
 
     BlockOpResponseProto status = BlockOpResponseProto.parseFrom(
         vintPrefixed(in));
-    checkSuccess(status, params.getPeer(), params.getBlock(), params.getFile());
+    checkSuccess(status, params.getSocket(), params.getBlock(),
+        params.getFile());
     ReadOpChecksumInfoProto checksumInfo =
       status.getReadOpChecksumInfo();
     DataChecksum checksum = DataTransferProtoUtil.fromProto(
@@ -382,28 +412,33 @@ public class RemoteBlockReader2  implements BlockReader {
                     params.getStartOffset() + " for file " + params.getFile());
     }
 
-    return new RemoteBlockReader2(params, checksum, firstChunkOffset);
+    return new RemoteBlockReader2(params, checksum, firstChunkOffset, ch);
   }
 
   static void checkSuccess(
-      BlockOpResponseProto status, Peer peer,
+      BlockOpResponseProto status, Socket sock,
       ExtendedBlock block, String file)
       throws IOException {
     if (status.getStatus() != Status.SUCCESS) {
       if (status.getStatus() == Status.ERROR_ACCESS_TOKEN) {
         throw new InvalidBlockTokenException(
             "Got access token error for OP_READ_BLOCK, self="
-                + peer.getLocalAddressString() + ", remote="
-                + peer.getRemoteAddressString() + ", for file " + file
+                + sock.getLocalSocketAddress() + ", remote="
+                + sock.getRemoteSocketAddress() + ", for file " + file
                 + ", for pool " + block.getBlockPoolId() + " block " 
                 + block.getBlockId() + "_" + block.getGenerationStamp());
       } else {
         throw new IOException("Got error for OP_READ_BLOCK, self="
-            + peer.getLocalAddressString() + ", remote="
-            + peer.getRemoteAddressString() + ", for file " + file
+            + sock.getLocalSocketAddress() + ", remote="
+            + sock.getRemoteSocketAddress() + ", for file " + file
             + ", for pool " + block.getBlockPoolId() + " block " 
             + block.getBlockId() + "_" + block.getGenerationStamp());
       }
     }
   }
+
+  @Override
+  public IOStreamPair getStreams() {
+    return ioStreams;
+  }
 }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/PeerCache.java → hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/SocketCache.java

@@ -18,55 +18,69 @@
 
 package org.apache.hadoop.hdfs;
 
+import java.io.Closeable;
+import java.net.Socket;
+import java.net.SocketAddress;
+
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map.Entry;
 
-import com.google.common.annotations.VisibleForTesting;
+import java.io.IOException;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.LinkedListMultimap;
 import org.apache.commons.logging.Log;
+import org.apache.hadoop.HadoopIllegalArgumentException;
 import org.apache.commons.logging.LogFactory;
-import org.apache.hadoop.hdfs.protocol.DatanodeID;
+import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.hdfs.protocol.datatransfer.IOStreamPair;
 import org.apache.hadoop.io.IOUtils;
-import org.apache.hadoop.hdfs.net.Peer;
 import org.apache.hadoop.util.Daemon;
+import org.apache.hadoop.util.StringUtils;
 import org.apache.hadoop.util.Time;
 
 /**
  * A cache of input stream sockets to Data Node.
  */
-class PeerCache {
-  private static final Log LOG = LogFactory.getLog(PeerCache.class);
-  
-  private static class Value {
-    private final Peer peer;
-    private final long time;
-
-    Value(Peer peer, long time) {
-      this.peer = peer;
-      this.time = time;
-    }
+class SocketCache {
+  private static final Log LOG = LogFactory.getLog(SocketCache.class);
 
-    Peer getPeer() {
-      return peer;
+  @InterfaceAudience.Private
+  static class SocketAndStreams implements Closeable {
+    public final Socket sock;
+    public final IOStreamPair ioStreams;
+    long createTime;
+    
+    public SocketAndStreams(Socket s, IOStreamPair ioStreams) {
+      this.sock = s;
+      this.ioStreams = ioStreams;
+      this.createTime = Time.monotonicNow();
+    }
+    
+    @Override
+    public void close() {
+      if (ioStreams != null) { 
+        IOUtils.closeStream(ioStreams.in);
+        IOUtils.closeStream(ioStreams.out);
+      }
+      IOUtils.closeSocket(sock);
     }
 
-    long getTime() {
-      return time;
+    public long getCreateTime() {
+      return this.createTime;
     }
   }
 
   private Daemon daemon;
   /** A map for per user per datanode. */
-  private static LinkedListMultimap<DatanodeID, Value> multimap =
+  private static LinkedListMultimap<SocketAddress, SocketAndStreams> multimap =
     LinkedListMultimap.create();
   private static int capacity;
   private static long expiryPeriod;
-  private static PeerCache instance = new PeerCache();
+  private static SocketCache scInstance = new SocketCache();
   private static boolean isInitedOnce = false;
  
-  public static synchronized PeerCache getInstance(int c, long e) {
+  public static synchronized SocketCache getInstance(int c, long e) {
     // capacity is only initialized once
     if (isInitedOnce == false) {
       capacity = c;
@@ -88,7 +102,7 @@ class PeerCache {
       }
     }
 
-    return instance;
+    return scInstance;
   }
 
   private boolean isDaemonStarted() {
@@ -105,45 +119,44 @@ class PeerCache {
       @Override
       public void run() {
         try {
-          PeerCache.this.run();
+          SocketCache.this.run();
         } catch(InterruptedException e) {
           //noop
         } finally {
-          PeerCache.this.clear();
+          SocketCache.this.clear();
         }
       }
 
       @Override
       public String toString() {
-        return String.valueOf(PeerCache.this);
+        return String.valueOf(SocketCache.this);
       }
     });
     daemon.start();
   }
 
   /**
-   * Get a cached peer connected to the given DataNode.
-   * @param dnId         The DataNode to get a Peer for.
-   * @return             An open Peer connected to the DN, or null if none
-   *                     was found. 
+   * Get a cached socket to the given address.
+   * @param remote  Remote address the socket is connected to.
+   * @return  A socket with unknown state, possibly closed underneath. Or null.
    */
-  public synchronized Peer get(DatanodeID dnId) {
+  public synchronized SocketAndStreams get(SocketAddress remote) {
 
     if (capacity <= 0) { // disabled
       return null;
     }
 
-    List<Value> sockStreamList = multimap.get(dnId);
+    List<SocketAndStreams> sockStreamList = multimap.get(remote);
     if (sockStreamList == null) {
       return null;
     }
 
-    Iterator<Value> iter = sockStreamList.iterator();
+    Iterator<SocketAndStreams> iter = sockStreamList.iterator();
     while (iter.hasNext()) {
-      Value candidate = iter.next();
+      SocketAndStreams candidate = iter.next();
       iter.remove();
-      if (!candidate.getPeer().isClosed()) {
-        return candidate.getPeer();
+      if (!candidate.sock.isClosed()) {
+        return candidate;
       }
     }
     return null;
@@ -153,22 +166,30 @@ class PeerCache {
    * Give an unused socket to the cache.
    * @param sock socket not used by anyone.
    */
-  public synchronized void put(DatanodeID dnId, Peer peer) {
-    Preconditions.checkNotNull(dnId);
-    Preconditions.checkNotNull(peer);
-    if (peer.isClosed()) return;
+  public synchronized void put(Socket sock, IOStreamPair ioStreams) {
+
+    Preconditions.checkNotNull(sock);
+    SocketAndStreams s = new SocketAndStreams(sock, ioStreams);
     if (capacity <= 0) {
       // Cache disabled.
-      IOUtils.cleanup(LOG, peer);
+      s.close();
       return;
     }
  
     startExpiryDaemon();
 
+    SocketAddress remoteAddr = sock.getRemoteSocketAddress();
+    if (remoteAddr == null) {
+      LOG.warn("Cannot cache (unconnected) socket with no remote address: " +
+               sock);
+      IOUtils.closeSocket(sock);
+      return;
+    }
+
     if (capacity == multimap.size()) {
       evictOldest();
     }
-    multimap.put(dnId, new Value(peer, Time.monotonicNow()));
+    multimap.put(remoteAddr, s);
   }
 
   public synchronized int size() {
@@ -180,17 +201,18 @@ class PeerCache {
    */
   private synchronized void evictExpired(long expiryPeriod) {
     while (multimap.size() != 0) {
-      Iterator<Entry<DatanodeID, Value>> iter =
+      Iterator<Entry<SocketAddress, SocketAndStreams>> iter =
         multimap.entries().iterator();
-      Entry<DatanodeID, Value> entry = iter.next();
+      Entry<SocketAddress, SocketAndStreams> entry = iter.next();
       // if oldest socket expired, remove it
       if (entry == null || 
-        Time.monotonicNow() - entry.getValue().getTime() <
+        Time.monotonicNow() - entry.getValue().getCreateTime() < 
         expiryPeriod) {
         break;
       }
-      IOUtils.cleanup(LOG, entry.getValue().getPeer());
       iter.remove();
+      SocketAndStreams s = entry.getValue();
+      s.close();
     }
   }
 
@@ -198,18 +220,16 @@ class PeerCache {
    * Evict the oldest entry in the cache.
    */
   private synchronized void evictOldest() {
-    // We can get the oldest element immediately, because of an interesting
-    // property of LinkedListMultimap: its iterator traverses entries in the
-    // order that they were added.
-    Iterator<Entry<DatanodeID, Value>> iter =
+    Iterator<Entry<SocketAddress, SocketAndStreams>> iter =
       multimap.entries().iterator();
     if (!iter.hasNext()) {
       throw new IllegalStateException("Cannot evict from empty cache! " +
         "capacity: " + capacity);
     }
-    Entry<DatanodeID, Value> entry = iter.next();
-    IOUtils.cleanup(LOG, entry.getValue().getPeer());
+    Entry<SocketAddress, SocketAndStreams> entry = iter.next();
     iter.remove();
+    SocketAndStreams s = entry.getValue();
+    s.close();
   }
 
   /**
@@ -233,10 +253,9 @@ class PeerCache {
   /**
    * Empty the cache, and close all sockets.
    */
-  @VisibleForTesting
-  synchronized void clear() {
-    for (Value value : multimap.values()) {
-      IOUtils.cleanup(LOG, value.getPeer());
+  private synchronized void clear() {
+    for (SocketAndStreams sockAndStream : multimap.values()) {
+      sockAndStream.close();
     }
     multimap.clear();
   }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/net/BasicInetPeer.java

@@ -1,121 +0,0 @@
-/**
- * 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.net;
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.OutputStream;
-import java.net.Socket;
-import java.nio.channels.ReadableByteChannel;
-
-/**
- * Represents a peer that we communicate with by using a basic Socket
- * that has no associated Channel.
- *
- */
-class BasicInetPeer implements Peer {
-  private final Socket socket;
-  private final OutputStream out;
-  private final InputStream in;
-  private final boolean isLocal;
-
-  public BasicInetPeer(Socket socket) throws IOException {
-    this.socket = socket;
-    this.out = socket.getOutputStream();
-    this.in = socket.getInputStream();
-    this.isLocal = socket.getInetAddress().equals(socket.getLocalAddress());
-  }
-
-  @Override
-  public ReadableByteChannel getInputStreamChannel() {
-    /*
-     * This Socket has no channel, so there's nothing to return here.
-     */
-    return null;
-  }
-
-  @Override
-  public void setReadTimeout(int timeoutMs) throws IOException {
-    socket.setSoTimeout(timeoutMs);
-  }
-
-  @Override
-  public int getReceiveBufferSize() throws IOException {
-    return socket.getReceiveBufferSize();
-  }
-
-  @Override
-  public boolean getTcpNoDelay() throws IOException {
-    return socket.getTcpNoDelay();
-  }
-
-  @Override
-  public void setWriteTimeout(int timeoutMs) {
-   /* 
-    * We can't implement write timeouts. :(
-    * 
-    * Java provides no facility to set a blocking write timeout on a Socket.
-    * You can simulate a blocking write with a timeout by using
-    * non-blocking I/O.  However, we can't use nio here, because this Socket
-    * doesn't have an associated Channel.
-    * 
-    * See http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4031100 for
-    * more details.
-    */
-  }
-
-  @Override
-  public boolean isClosed() {
-    return socket.isClosed();
-  }
-
-  @Override
-  public void close() throws IOException {
-    socket.close();
-  }
-
-  @Override
-  public String getRemoteAddressString() {
-    return socket.getRemoteSocketAddress().toString();
-  }
-
-  @Override
-  public String getLocalAddressString() {
-    return socket.getLocalSocketAddress().toString();
-  }
-  
-  @Override
-  public InputStream getInputStream() throws IOException {
-    return in;
-  }
-
-  @Override
-  public OutputStream getOutputStream() throws IOException {
-    return out;
-  }
-
-  @Override
-  public boolean isLocal() {
-    return isLocal;
-  }
-
-  @Override
-  public String toString() {
-    return "BasicInetPeer(" + socket.toString() + ")";
-  }
-}

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/net/EncryptedPeer.java

@@ -1,136 +0,0 @@
-/**
- * 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.net;
-
-import java.io.IOException;
-import org.apache.hadoop.classification.InterfaceAudience;
-import org.apache.hadoop.hdfs.protocol.datatransfer.DataTransferEncryptor;
-import org.apache.hadoop.hdfs.protocol.datatransfer.IOStreamPair;
-import org.apache.hadoop.hdfs.security.token.block.DataEncryptionKey;
-
-import java.io.InputStream;
-import java.io.OutputStream;
-import java.nio.channels.ReadableByteChannel;
-
-/**
- * Represents a peer that we communicate with by using an encrypted
- * communications medium.
- */
-@InterfaceAudience.Private
-public class EncryptedPeer implements Peer {
-  private final Peer enclosedPeer;
-
-  /**
-   * An encrypted InputStream.
-   */
-  private final InputStream in;
-  
-  /**
-   * An encrypted OutputStream.
-   */
-  private final OutputStream out;
-  
-  /**
-   * An encrypted ReadableByteChannel.
-   */
-  private final ReadableByteChannel channel;
-
-  public EncryptedPeer(Peer enclosedPeer, DataEncryptionKey key)
-      throws IOException {
-    this.enclosedPeer = enclosedPeer;
-    IOStreamPair ios = DataTransferEncryptor.getEncryptedStreams(
-        enclosedPeer.getOutputStream(), enclosedPeer.getInputStream(), key);
-    this.in = ios.in;
-    this.out = ios.out;
-    this.channel = ios.in instanceof ReadableByteChannel ? 
-        (ReadableByteChannel)ios.in : null;
-  }
-
-  @Override
-  public ReadableByteChannel getInputStreamChannel() {
-    return channel;
-  }
-
-  @Override
-  public void setReadTimeout(int timeoutMs) throws IOException {
-    enclosedPeer.setReadTimeout(timeoutMs);
-  }
-
-  @Override
-  public int getReceiveBufferSize() throws IOException {
-    return enclosedPeer.getReceiveBufferSize();
-  }
-
-  @Override
-  public boolean getTcpNoDelay() throws IOException {
-    return enclosedPeer.getTcpNoDelay();
-  }
-
-  @Override
-  public void setWriteTimeout(int timeoutMs) throws IOException {
-    enclosedPeer.setWriteTimeout(timeoutMs);
-  }
-
-  @Override
-  public boolean isClosed() {
-    return enclosedPeer.isClosed();
-  }
-
-  @Override
-  public void close() throws IOException {
-    try {
-      in.close();
-    } finally {
-      try {
-        out.close();
-      } finally {
-        enclosedPeer.close();
-      }
-    }
-  }
-
-  @Override
-  public String getRemoteAddressString() {
-    return enclosedPeer.getRemoteAddressString();
-  }
-
-  @Override
-  public String getLocalAddressString() {
-    return enclosedPeer.getLocalAddressString();
-  }
-
-  @Override
-  public InputStream getInputStream() throws IOException {
-    return in;
-  }
-
-  @Override
-  public OutputStream getOutputStream() throws IOException {
-    return out;
-  }
-
-  @Override
-  public boolean isLocal() {
-    return enclosedPeer.isLocal();
-  }
-
-  @Override
-  public String toString() {
-    return "EncryptedPeer(" + enclosedPeer + ")";
-  }
-}

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/net/NioInetPeer.java

@@ -1,125 +0,0 @@
-/**
- * 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.net;
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.OutputStream;
-import java.net.Socket;
-import java.nio.channels.ReadableByteChannel;
-
-import org.apache.hadoop.net.SocketInputStream;
-import org.apache.hadoop.net.SocketOutputStream;
-
-/**
- * Represents a peer that we communicate with by using non-blocking I/O 
- * on a Socket.
- */
-class NioInetPeer implements Peer {
-  private final Socket socket;
-
-  /**
-   * An InputStream which simulates blocking I/O with timeouts using NIO.
-   */
-  private final SocketInputStream in;
-  
-  /**
-   * An OutputStream which simulates blocking I/O with timeouts using NIO.
-   */
-  private final SocketOutputStream out;
-
-  private final boolean isLocal;
-
-  NioInetPeer(Socket socket) throws IOException {
-    this.socket = socket;
-    this.in = new SocketInputStream(socket.getChannel(), 0);
-    this.out = new SocketOutputStream(socket.getChannel(), 0);
-    this.isLocal = socket.getInetAddress().equals(socket.getLocalAddress());
-  }
-
-  @Override
-  public ReadableByteChannel getInputStreamChannel() {
-    return socket.getChannel();
-  }
-
-  @Override
-  public void setReadTimeout(int timeoutMs) throws IOException {
-    in.setTimeout(timeoutMs);
-  }
-
-  @Override
-  public int getReceiveBufferSize() throws IOException {
-    return socket.getReceiveBufferSize();
-  }
-
-  @Override
-  public boolean getTcpNoDelay() throws IOException {
-    return socket.getTcpNoDelay();
-  }
-
-  @Override
-  public void setWriteTimeout(int timeoutMs) throws IOException {
-    out.setTimeout(timeoutMs);
-  }
-
-  @Override
-  public boolean isClosed() {
-    return socket.isClosed();
-  }
-
-  @Override
-  public void close() throws IOException {
-    // We always close the outermost streams-- in this case, 'in' and 'out'
-    // Closing either one of these will also close the Socket.
-    try {
-      in.close();
-    } finally {
-      out.close();
-    }
-  }
-
-  @Override
-  public String getRemoteAddressString() {
-    return socket.getRemoteSocketAddress().toString();
-  }
-
-  @Override
-  public String getLocalAddressString() {
-    return socket.getLocalSocketAddress().toString();
-  }
-
-  @Override
-  public InputStream getInputStream() throws IOException {
-    return in;
-  }
-
-  @Override
-  public OutputStream getOutputStream() throws IOException {
-    return out;
-  }
-
-  @Override
-  public boolean isLocal() {
-    return isLocal;
-  }
-
-  @Override
-  public String toString() {
-    return "NioInetPeer(" + socket.toString() + ")";
-  }
-}

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/net/Peer.java

@@ -1,108 +0,0 @@
-/**
- * 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.net;
-
-import java.io.Closeable;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.OutputStream;
-import java.nio.channels.ReadableByteChannel;
-import org.apache.hadoop.classification.InterfaceAudience;
-
-/**
- * Represents a connection to a peer.
- */
-@InterfaceAudience.Private
-public interface Peer extends Closeable {
-  /**
-   * @return                The input stream channel associated with this
-   *                        peer, or null if it has none.
-   */
-  public ReadableByteChannel getInputStreamChannel();
-
-  /**
-   * Set the read timeout on this peer.
-   *
-   * @param timeoutMs       The timeout in milliseconds.
-   */
-  public void setReadTimeout(int timeoutMs) throws IOException;
-
-  /**
-   * @return                The receive buffer size.
-   */
-  public int getReceiveBufferSize() throws IOException;
-
-  /**
-   * @return                True if TCP_NODELAY is turned on.
-   */
-  public boolean getTcpNoDelay() throws IOException;
-
-  /**
-   * Set the write timeout on this peer.
-   *
-   * Note: this is not honored for BasicInetPeer.
-   * See {@link BasicSocketPeer#setWriteTimeout} for details.
-   * 
-   * @param timeoutMs       The timeout in milliseconds.
-   */
-  public void setWriteTimeout(int timeoutMs) throws IOException;
-
-  /**
-   * @return                true only if the peer is closed.
-   */
-  public boolean isClosed();
-  
-  /**
-   * Close the peer.
-   *
-   * It's safe to re-close a Peer that is already closed.
-   */
-  public void close() throws IOException;
-
-  /**
-   * @return               A string representing the remote end of our 
-   *                       connection to the peer.
-   */
-  public String getRemoteAddressString();
-
-  /**
-   * @return               A string representing the local end of our 
-   *                       connection to the peer.
-   */
-  public String getLocalAddressString();
-  
-  /**
-   * @return               An InputStream associated with the Peer.
-   *                       This InputStream will be valid until you close
-   *                       this peer with Peer#close.
-   */
-  public InputStream getInputStream() throws IOException;
-  
-  /**
-   * @return               An OutputStream associated with the Peer.
-   *                       This OutputStream will be valid until you close
-   *                       this peer with Peer#close.
-   */
-  public OutputStream getOutputStream() throws IOException;
-
-  /**
-   * @return               True if the peer resides on the same
-   *                       computer as we.
-   */
-  public boolean isLocal();
-}

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/net/PeerServer.java

@@ -1,60 +0,0 @@
-/**
- * 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.net;
-
-import java.io.Closeable;
-import org.apache.hadoop.classification.InterfaceAudience;
-import java.io.IOException;
-import java.net.SocketTimeoutException;
-
-@InterfaceAudience.Private
-public interface PeerServer extends Closeable {
-  /**
-   * Set the receive buffer size of the PeerServer.
-   * 
-   * @param size     The receive buffer size.
-   */
-  public void setReceiveBufferSize(int size) throws IOException;
-
-  /**
-   * Listens for a connection to be made to this server and accepts 
-   * it. The method blocks until a connection is made.
-   *
-   * @exception IOException  if an I/O error occurs when waiting for a
-   *               connection.
-   * @exception SecurityException  if a security manager exists and its  
-   *             <code>checkAccept</code> method doesn't allow the operation.
-   * @exception SocketTimeoutException if a timeout was previously set and
-   *             the timeout has been reached.
-   */
-  public Peer accept() throws IOException, SocketTimeoutException;
-
-  /**
-   * @return                 A string representation of the address we're
-   *                         listening on.
-   */
-  public String getListeningString();
-
-  /**
-   * Free the resources associated with this peer server.
-   * This normally includes sockets, etc.
-   *
-   * @throws IOException     If there is an error closing the PeerServer
-   */
-  public void close() throws IOException;
-}

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/net/TcpPeerServer.java

@@ -1,156 +0,0 @@
-/**
- * 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.net;
-
-import java.io.IOException;
-import java.net.InetSocketAddress;
-import java.net.ServerSocket;
-import java.net.Socket;
-import java.net.SocketTimeoutException;
-import java.nio.channels.ServerSocketChannel;
-import java.nio.channels.SocketChannel;
-
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
-import org.apache.hadoop.classification.InterfaceAudience;
-import org.apache.hadoop.hdfs.security.token.block.DataEncryptionKey;
-import org.apache.hadoop.hdfs.server.datanode.SecureDataNodeStarter.SecureResources;
-import org.apache.hadoop.io.IOUtils;
-import org.apache.hadoop.ipc.Server;
-
-@InterfaceAudience.Private
-public class TcpPeerServer implements PeerServer {
-  static Log LOG = LogFactory.getLog(TcpPeerServer.class);
-
-  private final ServerSocket serverSocket;
-
-  public static Peer peerFromSocket(Socket socket)
-      throws IOException {
-    Peer peer = null;
-    boolean success = false;
-    try {
-      // TCP_NODELAY is crucial here because of bad interactions between
-      // Nagle's Algorithm and Delayed ACKs. With connection keepalive
-      // between the client and DN, the conversation looks like:
-      //   1. Client -> DN: Read block X
-      //   2. DN -> Client: data for block X
-      //   3. Client -> DN: Status OK (successful read)
-      //   4. Client -> DN: Read block Y
-      // The fact that step #3 and #4 are both in the client->DN direction
-      // triggers Nagling. If the DN is using delayed ACKs, this results
-      // in a delay of 40ms or more.
-      //
-      // TCP_NODELAY disables nagling and thus avoids this performance
-      // disaster.
-      socket.setTcpNoDelay(true);
-      SocketChannel channel = socket.getChannel();
-      if (channel == null) {
-        peer = new BasicInetPeer(socket);
-      } else {
-        peer = new NioInetPeer(socket);
-      }
-      success = true;
-      return peer;
-    } finally {
-      if (!success) {
-        if (peer != null) peer.close();
-        socket.close();
-      }
-    }
-  }
-
-  public static Peer peerFromSocketAndKey(Socket s,
-        DataEncryptionKey key) throws IOException {
-    Peer peer = null;
-    boolean success = false;
-    try {
-      peer = peerFromSocket(s); 
-      if (key != null) {
-        peer = new EncryptedPeer(peer, key);
-      }
-      success = true;
-      return peer;
-    } finally {
-      if (!success) {
-        IOUtils.cleanup(null, peer);
-      }
-    }
-  }
-
-  /**
-   * Create a non-secure TcpPeerServer.
-   *
-   * @param socketWriteTimeout    The Socket write timeout in ms.
-   * @param bindAddr              The address to bind to.
-   * @throws IOException
-   */
-  public TcpPeerServer(int socketWriteTimeout,
-        InetSocketAddress bindAddr) throws IOException {
-    this.serverSocket = (socketWriteTimeout > 0) ?
-          ServerSocketChannel.open().socket() : new ServerSocket();
-    Server.bind(serverSocket, bindAddr, 0);
-  }
-
-  /**
-   * Create a secure TcpPeerServer.
-   *
-   * @param secureResources   Security resources.
-   */
-  public TcpPeerServer(SecureResources secureResources) {
-    this.serverSocket = secureResources.getStreamingSocket();
-  }
-  
-  /**
-   * @return     the IP address which this TcpPeerServer is listening on.
-   */
-  public InetSocketAddress getStreamingAddr() {
-    return new InetSocketAddress(
-        serverSocket.getInetAddress().getHostAddress(),
-        serverSocket.getLocalPort());
-  }
-
-  @Override
-  public void setReceiveBufferSize(int size) throws IOException {
-    this.serverSocket.setReceiveBufferSize(size);
-  }
-
-  @Override
-  public Peer accept() throws IOException, SocketTimeoutException {
-    Peer peer = peerFromSocket(serverSocket.accept());
-    return peer;
-  }
-
-  @Override
-  public String getListeningString() {
-    return serverSocket.getLocalSocketAddress().toString();
-  }
-  
-  @Override
-  public void close() throws IOException {
-    try {
-      serverSocket.close();
-    } catch(IOException e) {
-      LOG.error("error closing TcpPeerServer: ", e);
-    }
-  }
-
-  @Override
-  public String toString() {
-    return "TcpPeerServer(" + getListeningString() + ")";
-  }
-}

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/common/JspHelper.java

@@ -46,8 +46,6 @@ import org.apache.hadoop.hdfs.BlockReader;
 import org.apache.hadoop.hdfs.BlockReaderFactory;
 import org.apache.hadoop.hdfs.DFSClient.Conf;
 import org.apache.hadoop.hdfs.DFSUtil;
-import org.apache.hadoop.hdfs.net.TcpPeerServer;
-import org.apache.hadoop.hdfs.protocol.DatanodeID;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
@@ -209,14 +207,12 @@ public class JspHelper {
     // Use the block name for file name. 
     BlockReader blockReader = BlockReaderFactory.newBlockReader(
         new BlockReaderFactory.Params(new Conf(conf)).
-          setPeer(TcpPeerServer.peerFromSocketAndKey(s, encryptionKey)).
+          setSocket(s).
           setBlockToken(blockToken).setStartOffset(offsetIntoBlock).
           setLen(amtToRead).
+          setEncryptionKey(encryptionKey).
           setFile(BlockReaderFactory.getFileName(addr, poolId, blockId)).
-          setBlock(new ExtendedBlock(poolId, blockId, 0, genStamp)).
-          setDatanodeID(new DatanodeID(addr.getAddress().toString(), 
-              addr.getHostName(), poolId, addr.getPort(), 0, 0)));
-    
+          setBlock(new ExtendedBlock(poolId, blockId, 0, genStamp)));
     byte[] buf = new byte[(int)amtToRead];
     int readOffset = 0;
     int retries = 2;
@@ -234,7 +230,8 @@ public class JspHelper {
       amtToRead -= numRead;
       readOffset += numRead;
     }
-    blockReader.close(null);
+    blockReader = null;
+    s.close();
     out.print(HtmlQuoting.quoteHtmlChars(new String(buf)));
   }
 

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNode.java

@@ -90,7 +90,6 @@ import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.DFSUtil;
 import org.apache.hadoop.hdfs.HDFSPolicyProvider;
 import org.apache.hadoop.hdfs.HdfsConfiguration;
-import org.apache.hadoop.hdfs.net.TcpPeerServer;
 import org.apache.hadoop.hdfs.protocol.Block;
 import org.apache.hadoop.hdfs.protocol.BlockLocalPathInfo;
 import org.apache.hadoop.hdfs.protocol.ClientDatanodeProtocol;
@@ -523,19 +522,24 @@ public class DataNode extends Configured
   
   private void initDataXceiver(Configuration conf) throws IOException {
     // find free port or use privileged port provided
-    TcpPeerServer tcpPeerServer;
-    if (secureResources != null) {
-      tcpPeerServer = new TcpPeerServer(secureResources);
+    ServerSocket ss;
+    if (secureResources == null) {
+      InetSocketAddress addr = DataNode.getStreamingAddr(conf);
+      ss = (dnConf.socketWriteTimeout > 0) ? 
+          ServerSocketChannel.open().socket() : new ServerSocket();
+          Server.bind(ss, addr, 0);
     } else {
-      tcpPeerServer = new TcpPeerServer(dnConf.socketWriteTimeout,
-          DataNode.getStreamingAddr(conf));
+      ss = secureResources.getStreamingSocket();
     }
-    tcpPeerServer.setReceiveBufferSize(HdfsConstants.DEFAULT_DATA_SOCKET_SIZE);
-    streamingAddr = tcpPeerServer.getStreamingAddr();
+    ss.setReceiveBufferSize(HdfsConstants.DEFAULT_DATA_SOCKET_SIZE); 
+
+    streamingAddr = new InetSocketAddress(ss.getInetAddress().getHostAddress(),
+                                     ss.getLocalPort());
+
     LOG.info("Opened streaming server at " + streamingAddr);
     this.threadGroup = new ThreadGroup("dataXceiverServer");
     this.dataXceiverServer = new Daemon(threadGroup, 
-        new DataXceiverServer(tcpPeerServer, conf, this));
+        new DataXceiverServer(ss, conf, this));
     this.threadGroup.setDaemon(true); // auto destroy when empty
   }
   

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataXceiver.java

@@ -39,7 +39,6 @@ import java.nio.channels.ClosedChannelException;
 import java.util.Arrays;
 
 import org.apache.commons.logging.Log;
-import org.apache.hadoop.hdfs.net.Peer;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants;
@@ -65,6 +64,7 @@ import org.apache.hadoop.hdfs.server.protocol.DatanodeRegistration;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.io.MD5Hash;
 import org.apache.hadoop.net.NetUtils;
+import org.apache.hadoop.net.SocketInputWrapper;
 import org.apache.hadoop.security.token.SecretManager.InvalidToken;
 import org.apache.hadoop.security.token.Token;
 import org.apache.hadoop.util.DataChecksum;
@@ -79,7 +79,8 @@ class DataXceiver extends Receiver implements Runnable {
   public static final Log LOG = DataNode.LOG;
   static final Log ClientTraceLog = DataNode.ClientTraceLog;
   
-  private final Peer peer;
+  private final Socket s;
+  private final boolean isLocal; //is a local connection?
   private final String remoteAddress; // address of remote side
   private final String localAddress;  // local address of this daemon
   private final DataNode datanode;
@@ -87,7 +88,7 @@ class DataXceiver extends Receiver implements Runnable {
   private final DataXceiverServer dataXceiverServer;
   private final boolean connectToDnViaHostname;
   private long opStartTime; //the start time of receiving an Op
-  private final InputStream socketIn;
+  private final SocketInputWrapper socketIn;
   private OutputStream socketOut;
 
   /**
@@ -96,23 +97,25 @@ class DataXceiver extends Receiver implements Runnable {
    */
   private String previousOpClientName;
   
-  public static DataXceiver create(Peer peer, DataNode dn,
+  public static DataXceiver create(Socket s, DataNode dn,
       DataXceiverServer dataXceiverServer) throws IOException {
-    return new DataXceiver(peer, dn, dataXceiverServer);
+    return new DataXceiver(s, dn, dataXceiverServer);
   }
   
-  private DataXceiver(Peer peer, DataNode datanode,
+  private DataXceiver(Socket s, 
+      DataNode datanode, 
       DataXceiverServer dataXceiverServer) throws IOException {
 
-    this.peer = peer;
+    this.s = s;
     this.dnConf = datanode.getDnConf();
-    this.socketIn = peer.getInputStream();
-    this.socketOut = peer.getOutputStream();
+    this.socketIn = NetUtils.getInputStream(s);
+    this.socketOut = NetUtils.getOutputStream(s, dnConf.socketWriteTimeout);
+    this.isLocal = s.getInetAddress().equals(s.getLocalAddress());
     this.datanode = datanode;
     this.dataXceiverServer = dataXceiverServer;
     this.connectToDnViaHostname = datanode.getDnConf().connectToDnViaHostname;
-    remoteAddress = peer.getRemoteAddressString();
-    localAddress = peer.getLocalAddressString();
+    remoteAddress = s.getRemoteSocketAddress().toString();
+    localAddress = s.getLocalSocketAddress().toString();
 
     if (LOG.isDebugEnabled()) {
       LOG.debug("Number of active connections is: "
@@ -152,10 +155,11 @@ class DataXceiver extends Receiver implements Runnable {
   public void run() {
     int opsProcessed = 0;
     Op op = null;
-
-    dataXceiverServer.addPeer(peer);
+    
+    dataXceiverServer.childSockets.add(s);
+    
     try {
-      peer.setWriteTimeout(datanode.getDnConf().socketWriteTimeout);
+      
       InputStream input = socketIn;
       if (dnConf.encryptDataTransfer) {
         IOStreamPair encryptedStreams = null;
@@ -165,9 +169,8 @@ class DataXceiver extends Receiver implements Runnable {
               dnConf.encryptionAlgorithm);
         } catch (InvalidMagicNumberException imne) {
           LOG.info("Failed to read expected encryption handshake from client " +
-              "at " + peer.getRemoteAddressString() + ". Perhaps the client " +
-              "is running an older version of Hadoop which does not support " +
-              "encryption");
+              "at " + s.getInetAddress() + ". Perhaps the client is running an " +
+              "older version of Hadoop which does not support encryption");
           return;
         }
         input = encryptedStreams.in;
@@ -186,9 +189,9 @@ class DataXceiver extends Receiver implements Runnable {
         try {
           if (opsProcessed != 0) {
             assert dnConf.socketKeepaliveTimeout > 0;
-            peer.setReadTimeout(dnConf.socketKeepaliveTimeout);
+            socketIn.setTimeout(dnConf.socketKeepaliveTimeout);
           } else {
-            peer.setReadTimeout(dnConf.socketTimeout);
+            socketIn.setTimeout(dnConf.socketTimeout);
           }
           op = readOp();
         } catch (InterruptedIOException ignored) {
@@ -199,7 +202,7 @@ class DataXceiver extends Receiver implements Runnable {
           if (opsProcessed > 0 &&
               (err instanceof EOFException || err instanceof ClosedChannelException)) {
             if (LOG.isDebugEnabled()) {
-              LOG.debug("Cached " + peer + " closing after " + opsProcessed + " ops");
+              LOG.debug("Cached " + s.toString() + " closing after " + opsProcessed + " ops");
             }
           } else {
             throw err;
@@ -209,13 +212,13 @@ class DataXceiver extends Receiver implements Runnable {
 
         // restore normal timeout
         if (opsProcessed != 0) {
-          peer.setReadTimeout(dnConf.socketTimeout);
+          s.setSoTimeout(dnConf.socketTimeout);
         }
 
         opStartTime = now();
         processOp(op);
         ++opsProcessed;
-      } while (!peer.isClosed() && dnConf.socketKeepaliveTimeout > 0);
+      } while (!s.isClosed() && dnConf.socketKeepaliveTimeout > 0);
     } catch (Throwable t) {
       LOG.error(datanode.getDisplayName() + ":DataXceiver error processing " +
                 ((op == null) ? "unknown" : op.name()) + " operation " +
@@ -227,8 +230,9 @@ class DataXceiver extends Receiver implements Runnable {
             + datanode.getXceiverCount());
       }
       updateCurrentThreadName("Cleaning up");
-      dataXceiverServer.closePeer(peer);
       IOUtils.closeStream(in);
+      IOUtils.closeSocket(s);
+      dataXceiverServer.childSockets.remove(s);
     }
   }
 
@@ -282,9 +286,8 @@ class DataXceiver extends Receiver implements Runnable {
           ClientReadStatusProto stat = ClientReadStatusProto.parseFrom(
               HdfsProtoUtil.vintPrefixed(in));
           if (!stat.hasStatus()) {
-            LOG.warn("Client " + peer.getRemoteAddressString() +
-                " did not send a valid status code after reading. " +
-                "Will close connection.");
+            LOG.warn("Client " + s.getInetAddress() + " did not send a valid status " +
+                     "code after reading. Will close connection.");
             IOUtils.closeStream(out);
           }
         } catch (IOException ioe) {
@@ -317,7 +320,7 @@ class DataXceiver extends Receiver implements Runnable {
 
     //update metrics
     datanode.metrics.addReadBlockOp(elapsed());
-    datanode.metrics.incrReadsFromClient(peer.isLocal());
+    datanode.metrics.incrReadsFromClient(isLocal);
   }
 
   @Override
@@ -355,8 +358,8 @@ class DataXceiver extends Receiver implements Runnable {
       LOG.debug("isDatanode=" + isDatanode
           + ", isClient=" + isClient
           + ", isTransfer=" + isTransfer);
-      LOG.debug("writeBlock receive buf size " + peer.getReceiveBufferSize() +
-                " tcp no delay " + peer.getTcpNoDelay());
+      LOG.debug("writeBlock receive buf size " + s.getReceiveBufferSize() +
+                " tcp no delay " + s.getTcpNoDelay());
     }
 
     // We later mutate block's generation stamp and length, but we need to
@@ -387,8 +390,8 @@ class DataXceiver extends Receiver implements Runnable {
           stage != BlockConstructionStage.PIPELINE_CLOSE_RECOVERY) {
         // open a block receiver
         blockReceiver = new BlockReceiver(block, in, 
-            peer.getRemoteAddressString(),
-            peer.getLocalAddressString(),
+            s.getRemoteSocketAddress().toString(),
+            s.getLocalSocketAddress().toString(),
             stage, latestGenerationStamp, minBytesRcvd, maxBytesRcvd,
             clientname, srcDataNode, datanode, requestedChecksum);
       } else {
@@ -543,7 +546,7 @@ class DataXceiver extends Receiver implements Runnable {
 
     //update metrics
     datanode.metrics.addWriteBlockOp(elapsed());
-    datanode.metrics.incrWritesFromClient(peer.isLocal());
+    datanode.metrics.incrWritesFromClient(isLocal);
   }
 
   @Override
@@ -551,7 +554,7 @@ class DataXceiver extends Receiver implements Runnable {
       final Token<BlockTokenIdentifier> blockToken,
       final String clientName,
       final DatanodeInfo[] targets) throws IOException {
-    checkAccess(socketOut, true, blk, blockToken,
+    checkAccess(null, true, blk, blockToken,
         Op.TRANSFER_BLOCK, BlockTokenSecretManager.AccessMode.COPY);
     previousOpClientName = clientName;
     updateCurrentThreadName(Op.TRANSFER_BLOCK + " " + blk);
@@ -638,9 +641,8 @@ class DataXceiver extends Receiver implements Runnable {
     }
 
     if (!dataXceiverServer.balanceThrottler.acquire()) { // not able to start
-      String msg = "Not able to copy block " + block.getBlockId() + " " +
-          "to " + peer.getRemoteAddressString() + " because threads " +
-          "quota is exceeded.";
+      String msg = "Not able to copy block " + block.getBlockId() + " to " 
+      + s.getRemoteSocketAddress() + " because threads quota is exceeded."; 
       LOG.info(msg);
       sendResponse(ERROR, msg);
       return;
@@ -669,7 +671,7 @@ class DataXceiver extends Receiver implements Runnable {
       datanode.metrics.incrBytesRead((int) read);
       datanode.metrics.incrBlocksRead();
       
-      LOG.info("Copied " + block + " to " + peer.getRemoteAddressString());
+      LOG.info("Copied " + block + " to " + s.getRemoteSocketAddress());
     } catch (IOException ioe) {
       isOpSuccess = false;
       LOG.info("opCopyBlock " + block + " received exception " + ioe);
@@ -714,9 +716,8 @@ class DataXceiver extends Receiver implements Runnable {
     }
 
     if (!dataXceiverServer.balanceThrottler.acquire()) { // not able to start
-      String msg = "Not able to receive block " + block.getBlockId() +
-          " from " + peer.getRemoteAddressString() + " because threads " +
-          "quota is exceeded.";
+      String msg = "Not able to receive block " + block.getBlockId() + " from " 
+          + s.getRemoteSocketAddress() + " because threads quota is exceeded."; 
       LOG.warn(msg);
       sendResponse(ERROR, msg);
       return;
@@ -793,7 +794,7 @@ class DataXceiver extends Receiver implements Runnable {
       // notify name node
       datanode.notifyNamenodeReceivedBlock(block, delHint);
 
-      LOG.info("Moved " + block + " from " + peer.getRemoteAddressString());
+      LOG.info("Moved " + block + " from " + s.getRemoteSocketAddress());
       
     } catch (IOException ioe) {
       opStatus = ERROR;
@@ -816,7 +817,7 @@ class DataXceiver extends Receiver implements Runnable {
       try {
         sendResponse(opStatus, errMsg);
       } catch (IOException ioe) {
-        LOG.warn("Error writing reply back to " + peer.getRemoteAddressString());
+        LOG.warn("Error writing reply back to " + s.getRemoteSocketAddress());
       }
       IOUtils.closeStream(proxyOut);
       IOUtils.closeStream(blockReceiver);
@@ -870,7 +871,7 @@ class DataXceiver extends Receiver implements Runnable {
   }
   
 
-  private void checkAccess(OutputStream out, final boolean reply, 
+  private void checkAccess(DataOutputStream out, final boolean reply, 
       final ExtendedBlock blk,
       final Token<BlockTokenIdentifier> t,
       final Op op,
@@ -885,6 +886,11 @@ class DataXceiver extends Receiver implements Runnable {
       } catch(InvalidToken e) {
         try {
           if (reply) {
+            if (out == null) {
+              out = new DataOutputStream(
+                  NetUtils.getOutputStream(s, dnConf.socketWriteTimeout));
+            }
+            
             BlockOpResponseProto.Builder resp = BlockOpResponseProto.newBuilder()
               .setStatus(ERROR_ACCESS_TOKEN);
             if (mode == BlockTokenSecretManager.AccessMode.WRITE) {

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataXceiverServer.java

@@ -18,16 +18,18 @@
 package org.apache.hadoop.hdfs.server.datanode;
 
 import java.io.IOException;
+import java.net.ServerSocket;
+import java.net.Socket;
 import java.net.SocketTimeoutException;
 import java.nio.channels.AsynchronousCloseException;
+import java.util.Collections;
 import java.util.HashSet;
+import java.util.Iterator;
 import java.util.Set;
 
 import org.apache.commons.logging.Log;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hdfs.DFSConfigKeys;
-import org.apache.hadoop.hdfs.net.Peer;
-import org.apache.hadoop.hdfs.net.PeerServer;
 import org.apache.hadoop.hdfs.server.balancer.Balancer;
 import org.apache.hadoop.hdfs.util.DataTransferThrottler;
 import org.apache.hadoop.io.IOUtils;
@@ -43,9 +45,11 @@ import org.apache.hadoop.util.Daemon;
 class DataXceiverServer implements Runnable {
   public static final Log LOG = DataNode.LOG;
   
-  private final PeerServer peerServer;
-  private final DataNode datanode;
-  private final Set<Peer> peers = new HashSet<Peer>();
+  ServerSocket ss;
+  DataNode datanode;
+  // Record all sockets opened for data transfer
+  Set<Socket> childSockets = Collections.synchronizedSet(
+                                       new HashSet<Socket>());
   
   /**
    * Maximal number of concurrent xceivers per node.
@@ -105,10 +109,10 @@ class DataXceiverServer implements Runnable {
   long estimateBlockSize;
   
   
-  DataXceiverServer(PeerServer peerServer, Configuration conf,
+  DataXceiverServer(ServerSocket ss, Configuration conf, 
       DataNode datanode) {
     
-    this.peerServer = peerServer;
+    this.ss = ss;
     this.datanode = datanode;
     
     this.maxXceiverCount = 
@@ -126,10 +130,12 @@ class DataXceiverServer implements Runnable {
 
   @Override
   public void run() {
-    Peer peer = null;
     while (datanode.shouldRun) {
+      Socket s = null;
       try {
-        peer = peerServer.accept();
+        s = ss.accept();
+        s.setTcpNoDelay(true);
+        // Timeouts are set within DataXceiver.run()
 
         // Make sure the xceiver count is not exceeded
         int curXceiverCount = datanode.getXceiverCount();
@@ -140,7 +146,7 @@ class DataXceiverServer implements Runnable {
         }
 
         new Daemon(datanode.threadGroup,
-            DataXceiver.create(peer, datanode, this))
+            DataXceiver.create(s, datanode, this))
             .start();
       } catch (SocketTimeoutException ignored) {
         // wake up to see if should continue to run
@@ -151,10 +157,10 @@ class DataXceiverServer implements Runnable {
           LOG.warn(datanode.getDisplayName() + ":DataXceiverServer: ", ace);
         }
       } catch (IOException ie) {
-        IOUtils.cleanup(null, peer);
+        IOUtils.closeSocket(s);
         LOG.warn(datanode.getDisplayName() + ":DataXceiverServer: ", ie);
       } catch (OutOfMemoryError ie) {
-        IOUtils.cleanup(null, peer);
+        IOUtils.closeSocket(s);
         // DataNode can run out of memory if there is too many transfers.
         // Log the event, Sleep for 30 seconds, other transfers may complete by
         // then.
@@ -170,35 +176,33 @@ class DataXceiverServer implements Runnable {
         datanode.shouldRun = false;
       }
     }
-    synchronized (this) {
-      for (Peer p : peers) {
-        IOUtils.cleanup(LOG, p);
-      }
-    }
     try {
-      peerServer.close();
+      ss.close();
     } catch (IOException ie) {
       LOG.warn(datanode.getDisplayName()
           + " :DataXceiverServer: close exception", ie);
     }
   }
-
+  
   void kill() {
     assert datanode.shouldRun == false :
       "shoudRun should be set to false before killing";
     try {
-      this.peerServer.close();
+      this.ss.close();
     } catch (IOException ie) {
       LOG.warn(datanode.getDisplayName() + ":DataXceiverServer.kill(): ", ie);
     }
-  }
-  
-  synchronized void addPeer(Peer peer) {
-    peers.add(peer);
-  }
 
-  synchronized void closePeer(Peer peer) {
-    peers.remove(peer);
-    IOUtils.cleanup(null, peer);
+    // close all the sockets that were accepted earlier
+    synchronized (childSockets) {
+      for (Iterator<Socket> it = childSockets.iterator();
+           it.hasNext();) {
+        Socket thissock = it.next();
+        try {
+          thissock.close();
+        } catch (IOException e) {
+        }
+      }
+    }
   }
 }

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

@@ -43,7 +43,6 @@ import org.apache.hadoop.hdfs.DFSClient;
 import org.apache.hadoop.hdfs.DFSClient.Conf;
 import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.DFSUtil;
-import org.apache.hadoop.hdfs.net.TcpPeerServer;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.DirectoryListing;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
@@ -560,13 +559,13 @@ public class NamenodeFsck {
         
         blockReader = BlockReaderFactory.newBlockReader(
           new BlockReaderFactory.Params(new Conf(conf)).
-            setPeer(TcpPeerServer.peerFromSocketAndKey(s,
-                namenode.getRpcServer().getDataEncryptionKey())).
-            setBlock(block).
+            setSocket(s).setBlock(block).
             setFile(BlockReaderFactory.getFileName(targetAddr, 
                 block.getBlockPoolId(), block.getBlockId())).
             setBlockToken(lblock.getBlockToken()).
-            setDatanodeID(chosenNode));
+            setEncryptionKey(namenode.getRpcServer().getDataEncryptionKey()).
+            setLen(-1));
+        
       }  catch (IOException ex) {
         // Put chosen node into dead list, continue
         LOG.info("Failed to connect to " + targetAddr + ":" + ex);

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

@@ -32,7 +32,6 @@ import org.apache.hadoop.fs.CommonConfigurationKeys;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hdfs.DFSClient.Conf;
-import org.apache.hadoop.hdfs.net.TcpPeerServer;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
@@ -153,13 +152,13 @@ public class BlockReaderTestUtil {
 
     return BlockReaderFactory.newBlockReader(
         new BlockReaderFactory.Params(new Conf(conf)).
-          setPeer(TcpPeerServer.peerFromSocket(sock)).
+          setSocket(sock).
           setFile(targetAddr.toString() + ":" + block.getBlockId()).
           setBlock(block).setBlockToken(testBlock.getBlockToken()).
           setStartOffset(offset).setLen(lenToRead).
           setBufferSize(conf.getInt(
               CommonConfigurationKeys.IO_FILE_BUFFER_SIZE_KEY, 4096)).
-          setVerifyChecksum(true).setDatanodeID(nodes[0]));
+          setVerifyChecksum(true));
   }
 
   /**

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

@@ -61,7 +61,7 @@ public class TestClientBlockVerification {
         util.getBlockReader(testBlock, 0, FILE_SIZE_K * 1024));
     util.readAndCheckEOS(reader, FILE_SIZE_K * 1024, true);
     verify(reader).sendReadResult(Status.CHECKSUM_OK);
-    reader.close(null);
+    reader.close();
   }
 
   /**
@@ -76,7 +76,7 @@ public class TestClientBlockVerification {
     // We asked the blockreader for the whole file, and only read
     // half of it, so no CHECKSUM_OK
     verify(reader, never()).sendReadResult(Status.CHECKSUM_OK);
-    reader.close(null);
+    reader.close();
   }
 
   /**
@@ -92,7 +92,7 @@ public class TestClientBlockVerification {
     // And read half the file
     util.readAndCheckEOS(reader, FILE_SIZE_K * 1024 / 2, true);
     verify(reader).sendReadResult(Status.CHECKSUM_OK);
-    reader.close(null);
+    reader.close();
   }
 
   /**
@@ -111,7 +111,7 @@ public class TestClientBlockVerification {
             util.getBlockReader(testBlock, startOffset, length));
         util.readAndCheckEOS(reader, length, true);
         verify(reader).sendReadResult(Status.CHECKSUM_OK);
-        reader.close(null);
+        reader.close();
       }
     }
   }

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

@@ -18,20 +18,28 @@
 package org.apache.hadoop.hdfs;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertSame;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.Mockito.spy;
 
 import java.io.IOException;
 import java.net.InetSocketAddress;
-
-import junit.framework.Assert;
+import java.net.Socket;
+import java.security.PrivilegedExceptionAction;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
+import org.apache.hadoop.hdfs.protocol.LocatedBlock;
 import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
-import org.apache.hadoop.hdfs.net.Peer;
+import org.apache.hadoop.hdfs.server.datanode.DataNode;
 import org.apache.hadoop.security.token.Token;
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
 import org.junit.Test;
 import org.mockito.Matchers;
 import org.mockito.Mockito;
@@ -47,31 +55,59 @@ public class TestConnCache {
 
   static final int BLOCK_SIZE = 4096;
   static final int FILE_SIZE = 3 * BLOCK_SIZE;
+  final static int CACHE_SIZE = 4;
+  final static long CACHE_EXPIRY_MS = 200;
+  static Configuration conf = null;
+  static MiniDFSCluster cluster = null;
+  static FileSystem fs = null;
+  static SocketCache cache;
+
+  static final Path testFile = new Path("/testConnCache.dat");
+  static byte authenticData[] = null;
+
+  static BlockReaderTestUtil util = null;
+
 
   /**
    * A mock Answer to remember the BlockReader used.
    *
    * It verifies that all invocation to DFSInputStream.getBlockReader()
-   * use the same peer.
+   * use the same socket.
    */
   private class MockGetBlockReader implements Answer<RemoteBlockReader2> {
     public RemoteBlockReader2 reader = null;
-    private Peer peer = null;
+    private Socket sock = null;
 
     @Override
     public RemoteBlockReader2 answer(InvocationOnMock invocation) throws Throwable {
       RemoteBlockReader2 prevReader = reader;
       reader = (RemoteBlockReader2) invocation.callRealMethod();
-      if (peer == null) {
-        peer = reader.getPeer();
+      if (sock == null) {
+        sock = reader.dnSock;
       } else if (prevReader != null) {
-        Assert.assertSame("DFSInputStream should use the same peer",
-                   peer, reader.getPeer());
+        assertSame("DFSInputStream should use the same socket",
+                   sock, reader.dnSock);
       }
       return reader;
     }
   }
 
+  @BeforeClass
+  public static void setupCluster() throws Exception {
+    final int REPLICATION_FACTOR = 1;
+
+    /* create a socket cache. There is only one socket cache per jvm */
+    cache = SocketCache.getInstance(CACHE_SIZE, CACHE_EXPIRY_MS);
+
+    util = new BlockReaderTestUtil(REPLICATION_FACTOR);
+    cluster = util.getCluster();
+    conf = util.getConf();
+    fs = cluster.getFileSystem();
+
+    authenticData = util.writeFile(testFile, FILE_SIZE / 1024);
+  }
+
+
   /**
    * (Optionally) seek to position, read and verify data.
    *
@@ -81,10 +117,9 @@ public class TestConnCache {
                      long pos,
                      byte[] buffer,
                      int offset,
-                     int length,
-                     byte[] authenticData)
+                     int length)
       throws IOException {
-    Assert.assertTrue("Test buffer too small", buffer.length >= offset + length);
+    assertTrue("Test buffer too small", buffer.length >= offset + length);
 
     if (pos >= 0)
       in.seek(pos);
@@ -94,7 +129,7 @@ public class TestConnCache {
 
     while (length > 0) {
       int cnt = in.read(buffer, offset, length);
-      Assert.assertTrue("Error in read", cnt > 0);
+      assertTrue("Error in read", cnt > 0);
       offset += cnt;
       length -= cnt;
     }
@@ -109,23 +144,116 @@ public class TestConnCache {
     }
   }
 
+  /**
+   * Test the SocketCache itself.
+   */
+  @Test
+  public void testSocketCache() throws Exception {
+    // Make a client
+    InetSocketAddress nnAddr =
+        new InetSocketAddress("localhost", cluster.getNameNodePort());
+    DFSClient client = new DFSClient(nnAddr, conf);
+
+    // Find out the DN addr
+    LocatedBlock block =
+        client.getNamenode().getBlockLocations(
+            testFile.toString(), 0, FILE_SIZE)
+        .getLocatedBlocks().get(0);
+    DataNode dn = util.getDataNode(block);
+    InetSocketAddress dnAddr = dn.getXferAddress();
+
+
+    // Make some sockets to the DN
+    Socket[] dnSockets = new Socket[CACHE_SIZE];
+    for (int i = 0; i < dnSockets.length; ++i) {
+      dnSockets[i] = client.socketFactory.createSocket(
+          dnAddr.getAddress(), dnAddr.getPort());
+    }
+
+
+    // Insert a socket to the NN
+    Socket nnSock = new Socket(nnAddr.getAddress(), nnAddr.getPort());
+    cache.put(nnSock, null);
+    assertSame("Read the write", nnSock, cache.get(nnAddr).sock);
+    cache.put(nnSock, null);
+
+    // Insert DN socks
+    for (Socket dnSock : dnSockets) {
+      cache.put(dnSock, null);
+    }
+
+    assertEquals("NN socket evicted", null, cache.get(nnAddr));
+    assertTrue("Evicted socket closed", nnSock.isClosed());
+ 
+    // Lookup the DN socks
+    for (Socket dnSock : dnSockets) {
+      assertEquals("Retrieve cached sockets", dnSock, cache.get(dnAddr).sock);
+      dnSock.close();
+    }
+
+    assertEquals("Cache is empty", 0, cache.size());
+  }
+
+
+  /**
+   * Test the SocketCache expiry.
+   * Verify that socket cache entries expire after the set
+   * expiry time.
+   */
+  @Test
+  public void testSocketCacheExpiry() throws Exception {
+    // Make a client
+    InetSocketAddress nnAddr =
+        new InetSocketAddress("localhost", cluster.getNameNodePort());
+    DFSClient client = new DFSClient(nnAddr, conf);
+
+    // Find out the DN addr
+    LocatedBlock block =
+        client.getNamenode().getBlockLocations(
+            testFile.toString(), 0, FILE_SIZE)
+        .getLocatedBlocks().get(0);
+    DataNode dn = util.getDataNode(block);
+    InetSocketAddress dnAddr = dn.getXferAddress();
+
+
+    // Make some sockets to the DN and put in cache
+    Socket[] dnSockets = new Socket[CACHE_SIZE];
+    for (int i = 0; i < dnSockets.length; ++i) {
+      dnSockets[i] = client.socketFactory.createSocket(
+          dnAddr.getAddress(), dnAddr.getPort());
+      cache.put(dnSockets[i], null);
+    }
+
+    // Client side still has the sockets cached
+    assertEquals(CACHE_SIZE, client.socketCache.size());
+
+    //sleep for a second and see if it expired
+    Thread.sleep(CACHE_EXPIRY_MS + 1000);
+    
+    // Client side has no sockets cached
+    assertEquals(0, client.socketCache.size());
+
+    //sleep for another second and see if 
+    //the daemon thread runs fine on empty cache
+    Thread.sleep(CACHE_EXPIRY_MS + 1000);
+  }
+
+
   /**
    * Read a file served entirely from one DN. Seek around and read from
    * different offsets. And verify that they all use the same socket.
-   * @throws Exception 
+   *
+   * @throws java.io.IOException
    */
   @Test
   @SuppressWarnings("unchecked")
-  public void testReadFromOneDN() throws Exception {
-    BlockReaderTestUtil util = new BlockReaderTestUtil(1,
-        new HdfsConfiguration());
-    final Path testFile = new Path("/testConnCache.dat");
-    byte authenticData[] = util.writeFile(testFile, FILE_SIZE / 1024);
+  public void testReadFromOneDN() throws IOException {
+    LOG.info("Starting testReadFromOneDN()");
     DFSClient client = new DFSClient(
-        new InetSocketAddress("localhost",
-            util.getCluster().getNameNodePort()), util.getConf());
-    DFSInputStream in = Mockito.spy(client.open(testFile.toString()));
+        new InetSocketAddress("localhost", cluster.getNameNodePort()), conf);
+    DFSInputStream in = spy(client.open(testFile.toString()));
     LOG.info("opened " + testFile.toString());
+
     byte[] dataBuf = new byte[BLOCK_SIZE];
 
     MockGetBlockReader answer = new MockGetBlockReader();
@@ -142,15 +270,18 @@ public class TestConnCache {
                            Matchers.anyString());
 
     // Initial read
-    pread(in, 0, dataBuf, 0, dataBuf.length, authenticData);
+    pread(in, 0, dataBuf, 0, dataBuf.length);
     // Read again and verify that the socket is the same
-    pread(in, FILE_SIZE - dataBuf.length, dataBuf, 0, dataBuf.length,
-        authenticData);
-    pread(in, 1024, dataBuf, 0, dataBuf.length, authenticData);
-    // No seek; just read
-    pread(in, -1, dataBuf, 0, dataBuf.length, authenticData);
-    pread(in, 64, dataBuf, 0, dataBuf.length / 2, authenticData);
+    pread(in, FILE_SIZE - dataBuf.length, dataBuf, 0, dataBuf.length);
+    pread(in, 1024, dataBuf, 0, dataBuf.length);
+    pread(in, -1, dataBuf, 0, dataBuf.length);            // No seek; just read
+    pread(in, 64, dataBuf, 0, dataBuf.length / 2);
 
     in.close();
   }
+
+  @AfterClass
+  public static void teardownCluster() throws Exception {
+    util.shutdown();
+  }
 }

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

@@ -35,7 +35,6 @@ import org.apache.hadoop.fs.FSDataInputStream;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hdfs.MiniDFSCluster.DataNodeProperties;
-import org.apache.hadoop.hdfs.net.Peer;
 import org.apache.hadoop.hdfs.server.datanode.DataNode;
 import org.apache.hadoop.hdfs.server.datanode.DataNodeTestUtils;
 import org.apache.hadoop.hdfs.server.protocol.DatanodeRegistration;
@@ -93,13 +92,13 @@ public class TestDataTransferKeepalive {
     DFSTestUtil.createFile(fs, TEST_FILE, 1L, (short)1, 0L);
 
     // Clients that write aren't currently re-used.
-    assertEquals(0, dfsClient.peerCache.size());
+    assertEquals(0, dfsClient.socketCache.size());
     assertXceiverCount(0);
 
     // Reads the file, so we should get a
     // cached socket, and should have an xceiver on the other side.
     DFSTestUtil.readFile(fs, TEST_FILE);
-    assertEquals(1, dfsClient.peerCache.size());
+    assertEquals(1, dfsClient.socketCache.size());
     assertXceiverCount(1);
 
     // Sleep for a bit longer than the keepalive timeout
@@ -110,13 +109,13 @@ public class TestDataTransferKeepalive {
     // The socket is still in the cache, because we don't
     // notice that it's closed until we try to read
     // from it again.
-    assertEquals(1, dfsClient.peerCache.size());
+    assertEquals(1, dfsClient.socketCache.size());
     
     // Take it out of the cache - reading should
     // give an EOF.
-    Peer peer = dfsClient.peerCache.get(dn.getDatanodeId());
-    assertNotNull(peer);
-    assertEquals(-1, peer.getInputStream().read());
+    Socket s = dfsClient.socketCache.get(dnAddr).sock;
+    assertNotNull(s);
+    assertEquals(-1, NetUtils.getInputStream(s).read());
   }
 
   /**
@@ -175,14 +174,14 @@ public class TestDataTransferKeepalive {
     }
     
     DFSClient client = ((DistributedFileSystem)fs).dfs;
-    assertEquals(5, client.peerCache.size());
+    assertEquals(5, client.socketCache.size());
     
     // Let all the xceivers timeout
     Thread.sleep(1500);
     assertXceiverCount(0);
 
     // Client side still has the sockets cached
-    assertEquals(5, client.peerCache.size());
+    assertEquals(5, client.socketCache.size());
 
     // Reading should not throw an exception.
     DFSTestUtil.readFile(fs, TEST_FILE);

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

@@ -1,62 +0,0 @@
-/**
- * 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;
-
-import static org.junit.Assert.assertEquals;
-
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
-import org.apache.hadoop.fs.FileSystem;
-import org.apache.hadoop.fs.Path;
-import org.junit.Test;
-
-/**
- * This class tests disabling client connection caching in a single node
- * mini-cluster.
- */
-public class TestDisableConnCache {
-  static final Log LOG = LogFactory.getLog(TestDisableConnCache.class);
-
-  static final int BLOCK_SIZE = 4096;
-  static final int FILE_SIZE = 3 * BLOCK_SIZE;
-  
-  /**
-   * Test that the socket cache can be disabled by setting the capacity to
-   * 0. Regression test for HDFS-3365.
-   * @throws Exception 
-   */
-  @Test
-  public void testDisableCache() throws Exception {
-    HdfsConfiguration confWithoutCache = new HdfsConfiguration();
-    // Configure a new instance with no peer caching, ensure that it doesn't
-    // cache anything
-    confWithoutCache.setInt(
-        DFSConfigKeys.DFS_CLIENT_SOCKET_CACHE_CAPACITY_KEY, 0);
-    BlockReaderTestUtil util = new BlockReaderTestUtil(1, confWithoutCache);
-    final Path testFile = new Path("/testConnCache.dat");
-    util.writeFile(testFile, FILE_SIZE / 1024);
-    FileSystem fsWithoutCache = FileSystem.newInstance(util.getConf());
-    try {
-      DFSTestUtil.readFile(fsWithoutCache, testFile);
-      assertEquals(0, ((DistributedFileSystem)fsWithoutCache).dfs.peerCache.size());
-    } finally {
-      fsWithoutCache.close();
-      util.shutdown();
-    }
-  }
-}

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

@@ -1,218 +0,0 @@
-/**
- * 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;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertSame;
-import static org.junit.Assert.assertTrue;
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.OutputStream;
-import java.nio.channels.ReadableByteChannel;
-import java.util.HashSet;
-
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
-import org.apache.hadoop.hdfs.protocol.DatanodeID;
-import org.apache.hadoop.hdfs.net.Peer;
-import org.junit.Test;
-
-public class TestPeerCache {
-  static final Log LOG = LogFactory.getLog(TestPeerCache.class);
-
-  private static final int CAPACITY = 3;
-  private static final int EXPIRY_PERIOD = 20;
-  private static PeerCache cache =
-      PeerCache.getInstance(CAPACITY, EXPIRY_PERIOD);
-
-  private static class FakePeer implements Peer {
-    private boolean closed = false;
-
-    private DatanodeID dnId;
-
-    public FakePeer(DatanodeID dnId) {
-      this.dnId = dnId;
-    }
-
-    @Override
-    public ReadableByteChannel getInputStreamChannel() {
-      throw new UnsupportedOperationException();
-    }
-
-    @Override
-    public void setReadTimeout(int timeoutMs) throws IOException {
-      throw new UnsupportedOperationException();
-    }
-
-    @Override
-    public int getReceiveBufferSize() throws IOException {
-      throw new UnsupportedOperationException();
-    }
-
-    @Override
-    public boolean getTcpNoDelay() throws IOException {
-      return false;
-    }
-
-    @Override
-    public void setWriteTimeout(int timeoutMs) throws IOException {
-      throw new UnsupportedOperationException();
-    }
-
-    @Override
-    public boolean isClosed() {
-      return closed;
-    }
-  
-    @Override
-    public void close() throws IOException {
-      closed = true;
-    }
-
-    @Override
-    public String getRemoteAddressString() {
-      return dnId.getInfoAddr();
-    }
-
-    @Override
-    public String getLocalAddressString() {
-      return "127.0.0.1:123";
-    }
-
-    @Override
-    public InputStream getInputStream() throws IOException {
-      throw new UnsupportedOperationException();
-    }
-  
-    @Override
-    public OutputStream getOutputStream() throws IOException {
-      throw new UnsupportedOperationException();
-    }
-  
-    @Override
-    public boolean isLocal() {
-      return true;
-    }
-  
-    @Override
-    public String toString() {
-      return "FakePeer(dnId=" + dnId + ")";
-    }
-  }
-
-  @Test
-  public void testAddAndRetrieve() throws Exception {
-    DatanodeID dnId = new DatanodeID("192.168.0.1",
-          "fakehostname", "fake_storage_id",
-          100, 101, 102);
-    FakePeer peer = new FakePeer(dnId);
-    cache.put(dnId, peer);
-    assertTrue(!peer.isClosed());
-    assertEquals(1, cache.size());
-    assertEquals(peer, cache.get(dnId));
-    assertEquals(0, cache.size());
-    cache.clear();
-  }
-
-  @Test
-  public void testExpiry() throws Exception {
-    DatanodeID dnIds[] = new DatanodeID[CAPACITY];
-    FakePeer peers[] = new FakePeer[CAPACITY];
-    for (int i = 0; i < CAPACITY; ++i) {
-      dnIds[i] = new DatanodeID("192.168.0.1",
-          "fakehostname_" + i, "fake_storage_id",
-          100, 101, 102);
-      peers[i] = new FakePeer(dnIds[i]);
-    }
-    for (int i = 0; i < CAPACITY; ++i) {
-      cache.put(dnIds[i], peers[i]);
-    }
-    // Check that the peers are cached
-    assertEquals(CAPACITY, cache.size());
-
-    // Wait for the peers to expire
-    Thread.sleep(EXPIRY_PERIOD * 50);
-    assertEquals(0, cache.size());
-
-    // make sure that the peers were closed when they were expired
-    for (int i = 0; i < CAPACITY; ++i) {
-      assertTrue(peers[i].isClosed());
-    }
-
-    // sleep for another second and see if 
-    // the daemon thread runs fine on empty cache
-    Thread.sleep(EXPIRY_PERIOD * 50);
-    cache.clear();
-  }
-
-  @Test
-  public void testEviction() throws Exception {
-    DatanodeID dnIds[] = new DatanodeID[CAPACITY + 1];
-    FakePeer peers[] = new FakePeer[CAPACITY + 1];
-    for (int i = 0; i < dnIds.length; ++i) {
-      dnIds[i] = new DatanodeID("192.168.0.1",
-          "fakehostname_" + i, "fake_storage_id_" + i,
-          100, 101, 102);
-      peers[i] = new FakePeer(dnIds[i]);
-    }
-    for (int i = 0; i < CAPACITY; ++i) {
-      cache.put(dnIds[i], peers[i]);
-    }
-    // Check that the peers are cached
-    assertEquals(CAPACITY, cache.size());
-
-    // Add another entry and check that the first entry was evicted
-    cache.put(dnIds[CAPACITY], peers[CAPACITY]);
-    assertEquals(CAPACITY, cache.size());
-    assertSame(null, cache.get(dnIds[0]));
-
-    // Make sure that the other entries are still there
-    for (int i = 1; i < CAPACITY; ++i) {
-      Peer peer = cache.get(dnIds[i]);
-      assertSame(peers[i], peer);
-      assertTrue(!peer.isClosed());
-      peer.close();
-    }
-    assertEquals(1, cache.size());
-    cache.clear();
-  }
-
-  @Test
-  public void testMultiplePeersWithSameDnId() throws Exception {
-    DatanodeID dnId = new DatanodeID("192.168.0.1",
-          "fakehostname", "fake_storage_id",
-          100, 101, 102);
-    HashSet<FakePeer> peers = new HashSet<FakePeer>(CAPACITY);
-    for (int i = 0; i < CAPACITY; ++i) {
-      FakePeer peer = new FakePeer(dnId);
-      peers.add(peer);
-      cache.put(dnId, peer);
-    }
-    // Check that all of the peers ended up in the cache
-    assertEquals(CAPACITY, cache.size());
-    while (!peers.isEmpty()) {
-      Peer peer = cache.get(dnId);
-      assertTrue(peer != null);
-      assertTrue(!peer.isClosed());
-      peers.remove(peer);
-    }
-    assertEquals(0, cache.size());
-    cache.clear();
-  }
-}

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

@@ -0,0 +1,171 @@
+/**
+ * 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;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertSame;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.Mockito.spy;
+
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.net.Socket;
+import java.security.PrivilegedExceptionAction;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.FileSystem;
+import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
+import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
+import org.apache.hadoop.hdfs.protocol.LocatedBlock;
+import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
+import org.apache.hadoop.hdfs.server.datanode.DataNode;
+import org.apache.hadoop.security.token.Token;
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
+import org.junit.Test;
+import org.mockito.Matchers;
+import org.mockito.Mockito;
+import org.mockito.invocation.InvocationOnMock;
+import org.mockito.stubbing.Answer;
+
+/**
+ * This class tests the client connection caching in a single node
+ * mini-cluster.
+ */
+public class TestSocketCache {
+  static final Log LOG = LogFactory.getLog(TestSocketCache.class);
+
+  static final int BLOCK_SIZE = 4096;
+  static final int FILE_SIZE = 3 * BLOCK_SIZE;
+  final static int CACHE_SIZE = 4;
+  final static long CACHE_EXPIRY_MS = 200;
+  static Configuration conf = null;
+  static MiniDFSCluster cluster = null;
+  static FileSystem fs = null;
+  static SocketCache cache;
+
+  static final Path testFile = new Path("/testConnCache.dat");
+  static byte authenticData[] = null;
+
+  static BlockReaderTestUtil util = null;
+
+
+  /**
+   * A mock Answer to remember the BlockReader used.
+   *
+   * It verifies that all invocation to DFSInputStream.getBlockReader()
+   * use the same socket.
+   */
+  private class MockGetBlockReader implements Answer<RemoteBlockReader2> {
+    public RemoteBlockReader2 reader = null;
+    private Socket sock = null;
+
+    @Override
+    public RemoteBlockReader2 answer(InvocationOnMock invocation) throws Throwable {
+      RemoteBlockReader2 prevReader = reader;
+      reader = (RemoteBlockReader2) invocation.callRealMethod();
+      if (sock == null) {
+        sock = reader.dnSock;
+      } else if (prevReader != null) {
+        assertSame("DFSInputStream should use the same socket",
+                   sock, reader.dnSock);
+      }
+      return reader;
+    }
+  }
+
+  @BeforeClass
+  public static void setupCluster() throws Exception {
+    final int REPLICATION_FACTOR = 1;
+
+    HdfsConfiguration confWithoutCache = new HdfsConfiguration();
+    confWithoutCache.setInt(
+        DFSConfigKeys.DFS_CLIENT_SOCKET_CACHE_CAPACITY_KEY, 0);
+    util = new BlockReaderTestUtil(REPLICATION_FACTOR, confWithoutCache);
+    cluster = util.getCluster();
+    conf = util.getConf();
+
+    authenticData = util.writeFile(testFile, FILE_SIZE / 1024);
+  }
+
+
+  /**
+   * (Optionally) seek to position, read and verify data.
+   *
+   * Seek to specified position if pos is non-negative.
+   */
+  private void pread(DFSInputStream in,
+                     long pos,
+                     byte[] buffer,
+                     int offset,
+                     int length)
+      throws IOException {
+    assertTrue("Test buffer too small", buffer.length >= offset + length);
+
+    if (pos >= 0)
+      in.seek(pos);
+
+    LOG.info("Reading from file of size " + in.getFileLength() +
+             " at offset " + in.getPos());
+
+    while (length > 0) {
+      int cnt = in.read(buffer, offset, length);
+      assertTrue("Error in read", cnt > 0);
+      offset += cnt;
+      length -= cnt;
+    }
+
+    // Verify
+    for (int i = 0; i < length; ++i) {
+      byte actual = buffer[i];
+      byte expect = authenticData[(int)pos + i];
+      assertEquals("Read data mismatch at file offset " + (pos + i) +
+                   ". Expects " + expect + "; got " + actual,
+                   actual, expect);
+    }
+  }
+
+  
+  /**
+   * Test that the socket cache can be disabled by setting the capacity to
+   * 0. Regression test for HDFS-3365.
+   */
+  @Test
+  public void testDisableCache() throws IOException {
+    LOG.info("Starting testDisableCache()");
+
+    // Configure a new instance with no caching, ensure that it doesn't
+    // cache anything
+
+    FileSystem fsWithoutCache = FileSystem.newInstance(conf);
+    try {
+      DFSTestUtil.readFile(fsWithoutCache, testFile);
+      assertEquals(0, ((DistributedFileSystem)fsWithoutCache).dfs.socketCache.size());
+    } finally {
+      fsWithoutCache.close();
+    }
+  }
+
+  @AfterClass
+  public static void teardownCluster() throws Exception {
+    util.shutdown();
+  }
+}

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/blockmanagement/TestBlockTokenWithDFS.java

@@ -43,7 +43,6 @@ import org.apache.hadoop.hdfs.DFSClient.Conf;
 import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.DFSTestUtil;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
-import org.apache.hadoop.hdfs.net.TcpPeerServer;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
@@ -148,10 +147,9 @@ public class TestBlockTokenWithDFS {
           "test-blockpoolid", block.getBlockId());
       blockReader = BlockReaderFactory.newBlockReader(
           new BlockReaderFactory.Params(new Conf(conf)).
-            setPeer(TcpPeerServer.peerFromSocket(s)).
-            setBlock(block).setFile(file).
+            setSocket(s).setBlock(block).setFile(file).
             setBlockToken(lblock.getBlockToken()).setStartOffset(0).
-            setLen(-1).setDatanodeID(nodes[0]));
+            setLen(-1));
     } catch (IOException ex) {
       if (ex instanceof InvalidBlockTokenException) {
         assertFalse("OP_READ_BLOCK: access token is invalid, "

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestDataNodeVolumeFailure.java

@@ -39,7 +39,6 @@ import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.DFSTestUtil;
 import org.apache.hadoop.hdfs.HdfsConfiguration;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
-import org.apache.hadoop.hdfs.net.TcpPeerServer;
 import org.apache.hadoop.hdfs.protocol.Block;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
@@ -285,9 +284,8 @@ public class TestDataNodeVolumeFailure {
           setFile(BlockReaderFactory.getFileName(targetAddr, 
               "test-blockpoolid", block.getBlockId())).
           setBlock(block).setBlockToken(lblock.getBlockToken()).
-          setPeer(TcpPeerServer.peerFromSocket(s)).
-          setDatanodeID(datanode));
-    blockReader.close(null);
+          setSocket(s));
+    blockReader.close();
   }
   
   /**