HDFS-9259. Make SO_SNDBUF size configurable at DFSClient side for hdfs write scenario. (Mingliang Liu via mingma)

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DataStreamer.java

@@ -131,7 +131,9 @@ static Socket createSocketForPipeline(final DatanodeInfo first,
     NetUtils.connect(sock, isa, client.getRandomLocalInterfaceAddr(),
         conf.getSocketTimeout());
     sock.setSoTimeout(timeout);
-    sock.setSendBufferSize(HdfsConstants.DEFAULT_DATA_SOCKET_SIZE);
+    if (conf.getSocketSendBufferSize() > 0) {
+      sock.setSendBufferSize(conf.getSocketSendBufferSize());
+    }
     LOG.debug("Send buf size {}", sock.getSendBufferSize());
     return sock;
   }

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/client/HdfsClientConfigKeys.java

@@ -18,6 +18,7 @@
 package org.apache.hadoop.hdfs.client;
 
 import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.hdfs.protocol.HdfsConstants;
 
 import java.util.concurrent.TimeUnit;
 
@@ -58,6 +59,10 @@ public interface HdfsClientConfigKeys {
   String  DFS_CLIENT_WRITE_PACKET_SIZE_KEY = "dfs.client-write-packet-size";
   int     DFS_CLIENT_WRITE_PACKET_SIZE_DEFAULT = 64*1024;
   String  DFS_CLIENT_SOCKET_TIMEOUT_KEY = "dfs.client.socket-timeout";
+  String  DFS_CLIENT_SOCKET_SEND_BUFFER_SIZE_KEY =
+      "dfs.client.socket.send.buffer.size";
+  int     DFS_CLIENT_SOCKET_SEND_BUFFER_SIZE_DEFAULT =
+      HdfsConstants.DEFAULT_DATA_SOCKET_SIZE;
   String  DFS_CLIENT_SOCKET_CACHE_CAPACITY_KEY =
       "dfs.client.socketcache.capacity";
   int     DFS_CLIENT_SOCKET_CACHE_CAPACITY_DEFAULT = 16;

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/client/impl/DfsClientConf.java

@@ -56,6 +56,8 @@
 import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_SOCKET_CACHE_CAPACITY_KEY;
 import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_SOCKET_CACHE_EXPIRY_MSEC_DEFAULT;
 import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_SOCKET_CACHE_EXPIRY_MSEC_KEY;
+import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_SOCKET_SEND_BUFFER_SIZE_DEFAULT;
+import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_SOCKET_SEND_BUFFER_SIZE_KEY;
 import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_SOCKET_TIMEOUT_KEY;
 import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_USE_DN_HOSTNAME;
 import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_USE_DN_HOSTNAME_DEFAULT;
@@ -105,6 +107,7 @@ public class DfsClientConf {
   private final int writeMaxPackets;
   private final ByteArrayManager.Conf writeByteArrayManagerConf;
   private final int socketTimeout;
+  private final int socketSendBufferSize;
   private final long excludedNodesCacheExpiry;
   /** Wait time window (in msec) if BlockMissingException is caught. */
   private final int timeWindow;
@@ -172,6 +175,8 @@ public DfsClientConf(Configuration conf) {
     defaultChecksumOpt = getChecksumOptFromConf(conf);
     socketTimeout = conf.getInt(DFS_CLIENT_SOCKET_TIMEOUT_KEY,
         HdfsConstants.READ_TIMEOUT);
+    socketSendBufferSize = conf.getInt(DFS_CLIENT_SOCKET_SEND_BUFFER_SIZE_KEY,
+        DFS_CLIENT_SOCKET_SEND_BUFFER_SIZE_DEFAULT);
     /** dfs.write.packet.size is an internal config variable */
     writePacketSize = conf.getInt(
         DFS_CLIENT_WRITE_PACKET_SIZE_KEY,
@@ -407,6 +412,13 @@ public int getSocketTimeout() {
     return socketTimeout;
   }
 
+  /**
+   * @return the socketSendBufferSize
+   */
+  public int getSocketSendBufferSize() {
+    return socketSendBufferSize;
+  }
+
   /**
    * @return the excludedNodesCacheExpiry
    */

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

@@ -1584,6 +1584,9 @@ Release 2.8.0 - UNRELEASED
     HDFS-9292. Make TestFileConcorruption independent to underlying FsDataset
     Implementation. (lei)
 
+    HDFS-9259. Make SO_SNDBUF size configurable at DFSClient side for hdfs
+    write scenario. (Mingliang Liu via mingma)
+
   OPTIMIZATIONS
 
     HDFS-8026. Trace FSOutputSummer#writeChecksumChunks rather than

hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml

@@ -2141,6 +2141,18 @@
   </description>
 </property>
 
+<property>
+  <name>dfs.client.socket.send.buffer.size</name>
+  <value>131072</value>
+  <description>
+    Socket send buffer size for a write pipeline in DFSClient side.
+    This may affect TCP connection throughput.
+    If it is set to zero or negative value,
+    no buffer size will be set explicitly,
+    thus enable tcp auto-tuning on some system.
+  </description>
+</property>
+
 <property>
   <name>dfs.domain.socket.path</name>
   <value></value>

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

@@ -0,0 +1,96 @@
+/**
+ * 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 org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
+import org.apache.hadoop.test.GenericTestUtils;
+import org.apache.log4j.Level;
+
+import org.junit.After;
+import org.junit.Test;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+import java.net.Socket;
+
+import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_SOCKET_SEND_BUFFER_SIZE_DEFAULT;
+import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_SOCKET_SEND_BUFFER_SIZE_KEY;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+public class TestDFSClientSocketSize {
+  private static final Logger LOG = LoggerFactory.getLogger(
+      TestDFSClientSocketSize.class);
+  static {
+    GenericTestUtils.setLogLevel(DataStreamer.LOG, Level.ALL);
+  }
+
+  private final Configuration conf = new Configuration();
+  private MiniDFSCluster cluster;
+  private Socket socket;
+
+  @Test
+  public void testDefaultSendBufferSize() throws IOException {
+    socket = createSocket();
+    assertEquals("Send buffer size should be the default value.",
+        DFS_CLIENT_SOCKET_SEND_BUFFER_SIZE_DEFAULT,
+        socket.getSendBufferSize());
+  }
+
+  @Test
+  public void testSpecifiedSendBufferSize() throws IOException {
+    final int mySendBufferSize = 64 * 1024;  // 64 KB
+    conf.setInt(DFS_CLIENT_SOCKET_SEND_BUFFER_SIZE_KEY, mySendBufferSize);
+    socket = createSocket();
+    assertEquals("Send buffer size should be the customized value.",
+        mySendBufferSize, socket.getSendBufferSize());
+  }
+
+  @Test
+  public void testAutoTuningSendBufferSize() throws IOException {
+    conf.setInt(DFS_CLIENT_SOCKET_SEND_BUFFER_SIZE_KEY, 0);
+    socket = createSocket();
+    LOG.info("The auto tuned send buffer size is: {}",
+        socket.getSendBufferSize());
+    assertTrue("Send buffer size should be non-negative value which is " +
+        "determined by system (kernel).", socket.getSendBufferSize() > 0);
+  }
+
+  @After
+  public void tearDown() throws Exception {
+    if (socket != null) {
+      LOG.info("Closing the DFSClient socket.");
+    }
+    if (cluster != null) {
+      LOG.info("Shutting down MiniDFSCluster.");
+      cluster.shutdown();
+    }
+  }
+
+  private Socket createSocket() throws IOException {
+    cluster = new MiniDFSCluster.Builder(conf).numDataNodes(1).build();
+    cluster.waitActive();
+    LOG.info("MiniDFSCluster started.");
+    return DataStreamer.createSocketForPipeline(
+        new DatanodeInfo(cluster.dataNodes.get(0).datanode.getDatanodeId()),
+        1, cluster.getFileSystem().getClient());
+  }
+}