[HADOOP-9103] UTF8 class does not properly decode Unicode characters outside the basic multilingual plane

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.20.1
• Fix Version/s: 2.0.3-alpha
• Component/s: io

Environment

SUSE LINUX

• Hadoop Flags: Reviewed
• Tags: messy code,SecondaryNameNode,FSImage
• Assignee: Todd Lipcon
• Reporter: yixiaohua
• Created: 20/Apr/12 01:07
• Updated: 03/Sep/14 23:11
• Resolved: 05/Dec/12 21:14

Description

this the log information of the exception from the SecondaryNameNode:
2012-03-28 00:48:42,553 ERROR org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode: java.io.IOException: Found lease for
non-existent file /user/boss/pgv/fission/task16/split/_temporary/_attempt_201203271849_0016_r_000174_0/??@?????????????
??????????tor.qzone.qq.com/keypart-00174
at org.apache.hadoop.hdfs.server.namenode.FSImage.loadFilesUnderConstruction(FSImage.java:1211)
at org.apache.hadoop.hdfs.server.namenode.FSImage.loadFSImage(FSImage.java:959)
at org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode$CheckpointStorage.doMerge(SecondaryNameNode.java:589)
at org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode$CheckpointStorage.access$000(SecondaryNameNode.java:473)
at org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode.doMerge(SecondaryNameNode.java:350)
at org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode.doCheckpoint(SecondaryNameNode.java:314)
at org.apache.hadoop.hdfs.server.namenode.SecondaryNameNode.run(SecondaryNameNode.java:225)
at java.lang.Thread.run(Thread.java:619)

this is the log information about the file from namenode:
2012-03-28 00:32:26,528 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem.audit: ugi=boss,boss ip=/10.131.16.34 cmd=create src=/user/boss/pgv/fission/task16/split/_temporary/_attempt_201203271849_0016_r_000174_0/ @? tor.qzone.qq.com/keypart-00174 dst=null perm=boss:boss:rw-r-r-
2012-03-28 00:37:42,387 INFO org.apache.hadoop.hdfs.StateChange: BLOCK* NameSystem.allocateBlock: /user/boss/pgv/fission/task16/split/_temporary/_attempt_201203271849_0016_r_000174_0/ @? tor.qzone.qq.com/keypart-00174. blk_2751836614265659170_184668759
2012-03-28 00:37:42,696 INFO org.apache.hadoop.hdfs.StateChange: DIR* NameSystem.completeFile: file /user/boss/pgv/fission/task16/split/_temporary/_attempt_201203271849_0016_r_000174_0/ @? tor.qzone.qq.com/keypart-00174 is closed by DFSClient_attempt_201203271849_0016_r_000174_0
2012-03-28 00:37:50,315 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem.audit: ugi=boss,boss ip=/10.131.16.34 cmd=rename src=/user/boss/pgv/fission/task16/split/_temporary/_attempt_201203271849_0016_r_000174_0/ @? tor.qzone.qq.com/keypart-00174 dst=/user/boss/pgv/fission/task16/split/ @? tor.qzone.qq.com/keypart-00174 perm=boss:boss:rw-r-r-

after check the code that save FSImage,I found there are a problem that maybe a bug of HDFS Code,I past below:
------------this is the saveFSImage method in FSImage.java, I make some mark at the problem code-----------

/**

• Save the contents of the FS image to the file.
  */
  void saveFSImage(File newFile) throws IOException {
  FSNamesystem fsNamesys = FSNamesystem.getFSNamesystem();
  FSDirectory fsDir = fsNamesys.dir;
  long startTime = FSNamesystem.now();
  //
  // Write out data
  //
  DataOutputStream out = new DataOutputStream(
  new BufferedOutputStream(
  new FileOutputStream(newFile)));
  try { ......... // save the rest of the nodes saveImage(strbuf, 0, fsDir.rootDir, out);------------------problem fsNamesys.saveFilesUnderConstruction(out);------------------problem detail is below strbuf = null; }

  finally

  { out.close(); }

LOG.info("Image file of size " + newFile.length() + " saved in "
+ (FSNamesystem.now() - startTime)/1000 + " seconds.");
}

/**

• Save file tree image starting from the given root.
• This is a recursive procedure, which first saves all children of
• a current directory and then moves inside the sub-directories.
  */
  private static void saveImage(ByteBuffer parentPrefix,
  int prefixLength,
  INodeDirectory current,
  DataOutputStream out) throws IOException
  Unknown macro: { int newPrefixLength = prefixLength; if (current.getChildrenRaw() == null) return; for(INode child }

// Helper function that writes an INodeUnderConstruction
// into the input stream
//
static void writeINodeUnderConstruction(DataOutputStream out,
INodeFileUnderConstruction cons,
String path)
throws IOException

{ writeString(path, out);------------------problem .......... }

static private final UTF8 U_STR = new UTF8();
static void writeString(String str, DataOutputStream out) throws IOException

{ U_STR.set(str); U_STR.write(out);------------------problem }

/**

• Converts a string to a byte array using UTF8 encoding.
  */
  static byte[] string2Bytes(String str)
  Unknown macro: { try { return str.getBytes("UTF8");------------------problem } catch(UnsupportedEncodingException e) { assert false : "UTF8 encoding is not supported "; } return null; }

  -----------------------------------------below is the explain-----------------------
  in saveImage method: child.getLocalNameBytes(),the bytes use the method of str.getBytes("UTF8");

but in writeINodeUnderConstruction, the bytes user the method of Class UTF8 to get the bytes.

I make a test use our messy code file name , found the the two bytes arrsy are not equal. so I both use the class UTF8,then the problem desappare.

I think this is a bug of HDFS or UTF8.

Issue Links

• breaks: HDFS-4282 TestEditLog.testFuzzSequences FAILED in all pre-commit test
• is related to: HADOOP-9544 backport UTF8 encoding fixes to branch-1