svn commit: r1382409 - in /hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs: CHANGES.txt src/main/java/org/apache/hadoop/hdfs/DFSClient.java src/main/java/org/apache/hadoop/hdfs/DFSInputStream.java

[eli]

Author: eli
Date: Sun Sep  9 06:37:31 2012
New Revision: 1382409

URL: http://svn.apache.org/viewvc?rev=1382409&view=rev
Log:
HDFS-2757. Cannot read a local block that's being written to when using the 
local read short circuit. Contributed by Jean-Daniel Cryans

Modified:
    hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
    
hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSClient.java
    
hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSInputStream.java

Modified: hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
URL: 
http://svn.apache.org/viewvc/hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt?rev=1382409&r1=1382408&r2=1382409&view=diff
==============================================================================
--- hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt (original)
+++ hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt Sun Sep  9 
06:37:31 2012
@@ -744,6 +744,9 @@ Release 2.0.2-alpha - 2012-09-07 
     HDFS-3809. Make BKJM use protobufs for all serialization with ZK.(Ivan 
Kelly via umamahesh)
 
     HDFS-3895. hadoop-client must include commons-cli (tucu)
+
+    HDFS-2757. Cannot read a local block that's being written to when
+    using the local read short circuit. (Jean-Daniel Cryans via eli)
     
   BREAKDOWN OF HDFS-3042 SUBTASKS
 

Modified: 
hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSClient.java
URL: 
http://svn.apache.org/viewvc/hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSClient.java?rev=1382409&r1=1382408&r2=1382409&view=diff
==============================================================================
--- 
hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSClient.java
 (original)
+++ 
hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSClient.java
 Sun Sep  9 06:37:31 2012
@@ -2074,10 +2074,7 @@ public class DFSClient implements java.i
   }
   
   boolean shouldTryShortCircuitRead(InetSocketAddress targetAddr) {
-    if (shortCircuitLocalReads && isLocalAddress(targetAddr)) {
-      return true;
-    }
-    return false;
+    return shortCircuitLocalReads && isLocalAddress(targetAddr);
   }
 
   void reportChecksumFailure(String file, ExtendedBlock blk, DatanodeInfo dn) {

Modified: 
hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSInputStream.java
URL: 
http://svn.apache.org/viewvc/hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSInputStream.java?rev=1382409&r1=1382408&r2=1382409&view=diff
==============================================================================
--- 
hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSInputStream.java
 (original)
+++ 
hadoop/common/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSInputStream.java
 Sun Sep  9 06:37:31 2012
@@ -243,6 +243,10 @@ public class DFSInputStream extends FSIn
         locatedBlocks.getFileLength() + lastBlockBeingWrittenLength;
   }
 
+  private synchronized boolean blockUnderConstruction() {
+    return locatedBlocks.isUnderConstruction();
+  }
+
   /**
    * Returns the datanode from which the stream is currently reading.
    */
@@ -878,7 +882,9 @@ public class DFSInputStream extends FSIn
                                        String clientName)
       throws IOException {
     
-    if (dfsClient.shouldTryShortCircuitRead(dnAddr)) {
+    // Can't local read a block under construction, see HDFS-2757
+    if (dfsClient.shouldTryShortCircuitRead(dnAddr) &&
+        !blockUnderConstruction()) {
       return DFSClient.getLocalBlockReader(dfsClient.conf, src, block,
           blockToken, chosenNode, dfsClient.hdfsTimeout, startOffset,
           dfsClient.connectToDnViaHostname());