[HDFS-4661] fix various bugs in short circuit read

• Type: Sub-task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.1.0-beta
• Component/s: datanode, hdfs-client
• Hadoop Flags: Reviewed
• Assignee: Colin McCabe
• Reporter: Colin McCabe
• Created: 02/Apr/13 17:36
• Updated: 28/Sep/15 20:51
• Resolved: 10/May/13 00:03

Description

• For the log statement in DataXceiver below,
  • it has two String.format(..);
  • it uses %s for string constants.

    BlockSender.ClientTraceLog.info(String.format(
              String.format(
                "src: %s, dest: %s, op: %s, blockid: %s, srvID: %s, " +
                  "success: %b",
                "127.0.0.1",                   // src IP
                "127.0.0.1",                   // dst IP
                "REQUEST_SHORT_CIRCUIT_FDS",   // operation
                blk.getBlockId(),             // block id
                dnR.getStorageID(),
                (fis != null)
              )));
    

• The new method getShortCircuitFdsForRead(..) added to FsDatasetSpi is unecssary.

• FileInputStreamCache.Key.equals mistakenly uses & instead of &&.

• In FileInputStreamCache.CacheCleaner, it uncessarily call map.entries().iterator()) for each loop.

• The cache objects should not be passed in BlockReader.close(..)