dfs -put hangs
--------------

                 Key: HADOOP-2647
                 URL: https://issues.apache.org/jira/browse/HADOOP-2647
             Project: Hadoop
          Issue Type: Bug
          Components: dfs
    Affects Versions: 0.15.1
         Environment: LINUX
            Reporter: lohit vijayarenu


We saw a case where dfs -put hung while copying a 2GB file for over 20 hours.
When we took a look at the stack trace of process the main thread was waiting 
for confirmation from namenode for complete status.
only 4 blocks were copied and 5th block was missing when we ran fsck on the 
partially transfered file. 

There are 2 problems we saw here.

1. DFS client hung without a timeout when there is no response from namenode.
2. In IOUtils::copyBytes(InputStream in, OutputStream out, int buffSize, 
boolean close)
During copy, if there is an exception, the out.close() is called. Exception is 
not caught. Which is why we see a close call in the stack trace. 

When we checked for block IDs in namenode log. For the block which was missing, 
there was only one response to namenode instead of three.
This close state coupled with namenode not reporting the error back might have 
cause the whole process to hang.

Opening this JIRA to see if we could add checks to the two problems mentioned 
above.

<stack trace of main thread>
"main" prio=10 tid=0x0805a000 nid=0x5b53 waiting on condition 
[0xf7e64000..0xf7e65288]   java.lang.Thread.State: TIMED_WAITING (sleeping)
  at java.lang.Thread.sleep(Native Method) 
  at org.apache.hadoop.dfs.DFSClient$DFSOutputStream.close(DFSClient.java:1751) 
 - locked <0x77d593a0> (a org.apache.hadoop.dfs.DFSClient$DFSOutputStream)  at 
org.apache.hadoop.fs.FSDataOutputStream$PositionCache.close(FSDataOutputStream.java:49)
  at org.apache.hadoop.fs.FSDataOutputStream.close(FSDataOutputStream.java:64)  
at org.apache.hadoop.io.IOUtils.copyBytes(IOUtils.java:55)
  at org.apache.hadoop.io.IOUtils.copyBytes(IOUtils.java:83)  at 
org.apache.hadoop.fs.FileUtil.copy(FileUtil.java:140)
  at org.apache.hadoop.fs.FileSystem.copyFromLocalFile(FileSystem.java:826)
  at org.apache.hadoop.fs.FsShell.copyFromLocal(FsShell.java:114)
  at org.apache.hadoop.fs.FsShell.run(FsShell.java:1354)
  at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:65)  at 
org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:79)
  at org.apache.hadoop.fs.FsShell.main(FsShell.java:1472)
</stack trace of main thread>


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