From 6f335e4f0ea857ef11ff24c392bf6e549b5db406 Mon Sep 17 00:00:00 2001
From: Haohui Mai <wheat9@apache.org>
Date: Tue, 29 Sep 2015 14:59:13 -0700
Subject: [PATCH] HDFS-8696. Make the lower and higher watermark in the DN
 Netty server configurable. Contributed by Xiaobing Zhou.

---
 hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt       |  3 +++
 .../org/apache/hadoop/hdfs/DFSConfigKeys.java     |  6 ++++++
 .../server/datanode/web/DatanodeHttpServer.java   | 15 +++++++++++++++
 3 files changed, 24 insertions(+)

diff --git a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
index 0bca0e4a3c6..7b62b97500a 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
+++ b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
@@ -997,6 +997,9 @@ Release 2.8.0 - UNRELEASED
     HDFS-9165. Move entries in META-INF/services/o.a.h.fs.FileSystem to
     hdfs-client. (Mingliang Liu via wheat9)
 
+    HDFS-8696. Make the lower and higher watermark in the DN Netty server
+    configurable. (Xiaobing Zhou via wheat9)
+
   OPTIMIZATIONS
 
     HDFS-8026. Trace FSOutputSummer#writeChecksumChunks rather than
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java
index 055d7e34c52..37d74e3ff8c 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java
@@ -63,6 +63,12 @@ public class DFSConfigKeys extends CommonConfigurationKeys {
       HdfsClientConfigKeys.DFS_HDFS_BLOCKS_METADATA_ENABLED_DEFAULT;
   public static final String DFS_WEBHDFS_ACL_PERMISSION_PATTERN_DEFAULT =
       HdfsClientConfigKeys.DFS_WEBHDFS_ACL_PERMISSION_PATTERN_DEFAULT;
+  public static final String  DFS_WEBHDFS_NETTY_LOW_WATERMARK =
+      "dfs.webhdfs.netty.low.watermark";
+  public static final int  DFS_WEBHDFS_NETTY_LOW_WATERMARK_DEFAULT = 32768;
+  public static final String  DFS_WEBHDFS_NETTY_HIGH_WATERMARK =
+      "dfs.webhdfs.netty.high.watermark";
+  public static final int  DFS_WEBHDFS_NETTY_HIGH_WATERMARK_DEFAULT = 65535;
 
   // HA related configuration
   public static final String  DFS_DATANODE_RESTART_REPLICA_EXPIRY_KEY = "dfs.datanode.restart.replica.expiration";
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/web/DatanodeHttpServer.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/web/DatanodeHttpServer.java
index 62c98e7d24c..441d5200579 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/web/DatanodeHttpServer.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/web/DatanodeHttpServer.java
@@ -21,6 +21,7 @@
 import io.netty.channel.ChannelFactory;
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelInitializer;
+import io.netty.channel.ChannelOption;
 import io.netty.channel.ChannelPipeline;
 import io.netty.channel.EventLoopGroup;
 import io.netty.channel.nio.NioEventLoopGroup;
@@ -30,10 +31,12 @@
 import io.netty.handler.codec.http.HttpResponseEncoder;
 import io.netty.handler.ssl.SslHandler;
 import io.netty.handler.stream.ChunkedWriteHandler;
+
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.permission.FsPermission;
+import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.DFSUtil;
 import org.apache.hadoop.hdfs.server.common.JspHelper;
 import org.apache.hadoop.hdfs.server.datanode.BlockScanner;
@@ -117,6 +120,18 @@ protected void initChannel(SocketChannel ch) throws Exception {
               conf, confForCreate));
         }
       });
+
+      this.httpServer.childOption(
+          ChannelOption.WRITE_BUFFER_HIGH_WATER_MARK,
+          conf.getInt(
+              DFSConfigKeys.DFS_WEBHDFS_NETTY_HIGH_WATERMARK,
+              DFSConfigKeys.DFS_WEBHDFS_NETTY_HIGH_WATERMARK_DEFAULT));
+      this.httpServer.childOption(
+          ChannelOption.WRITE_BUFFER_LOW_WATER_MARK,
+          conf.getInt(
+              DFSConfigKeys.DFS_WEBHDFS_NETTY_LOW_WATERMARK,
+              DFSConfigKeys.DFS_WEBHDFS_NETTY_LOW_WATERMARK_DEFAULT));
+
       if (externalHttpChannel == null) {
         httpServer.channel(NioServerSocketChannel.class);
       } else {