svn merge -c -1453709 for reverting HDFS-4551.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1.1@1453710 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -20,9 +20,6 @@ Release 1.1.2 - 2013.01.30
     HADOOP-8567. Port conf servlet to dump running configuration to branch 1.x.
     (Jing Zhao via suresh)
 
-    HDFS-4551. When copying bytes in DatanodeWebHdfsMethods OPEN, use 4096 buffer size
-    to improve performance.  (Mark Wagner via szetszwo)
-
   BUG FIXES
 
     HADOOP-8419. Fixed GzipCode NPE reset for IBM JDK. (Yu Li via eyang)

src/hdfs/org/apache/hadoop/hdfs/server/datanode/web/resources/DatanodeWebHdfsMethods.java

@@ -350,9 +350,9 @@ public class DatanodeWebHdfsMethods {
           DFSClient client = dfsclient;
           try {
             if (n == null) {
-              IOUtils.copyBytes(dfsin, out, 4096);
+              IOUtils.copyBytes(dfsin, out, b);
             } else {
-              IOUtils.copyBytes(dfsin, out, n, 4096, false);
+              IOUtils.copyBytes(dfsin, out, n, b, false);
             }
             dfsin.close();
             dfsin = null;