Hadoop HDFS
  1. Hadoop HDFS
  2. HDFS-5790

LeaseManager.findPath is very slow when many leases need recovery

    Details

    • Type: Bug Bug
    • Status: Closed
    • Priority: Major Major
    • Resolution: Fixed
    • Affects Version/s: 2.3.0
    • Fix Version/s: 2.4.0
    • Component/s: namenode, performance
    • Labels:
      None
    • Hadoop Flags:
      Reviewed
    • Release Note:
      Committed to branch-2 and trunk.

      Description

      We recently saw an issue where the NN restarted while tens of thousands of files were open. The NN then ended up spending multiple seconds for each commitBlockSynchronization() call, spending most of its time inside LeaseManager.findPath(). findPath currently works by looping over all files held for a given writer, and traversing the filesystem for each one. This takes way too long when tens of thousands of files are open by a single writer.

      1. hdfs-5790.txt
        4 kB
        Todd Lipcon
      2. hdfs-5790.txt
        5 kB
        Todd Lipcon

        Issue Links

          Activity

          Todd Lipcon created issue -
          Todd Lipcon made changes -
          Field Original Value New Value
          Attachment hdfs-5790.txt [ 12624229 ]
          Todd Lipcon made changes -
          Assignee Todd Lipcon [ tlipcon ]
          Todd Lipcon made changes -
          Status Open [ 1 ] Patch Available [ 10002 ]
          Todd Lipcon made changes -
          Attachment hdfs-5790.txt [ 12624258 ]
          Arun C Murthy made changes -
          Affects Version/s 2.3.0 [ 12325255 ]
          Affects Version/s 2.4.0 [ 12324588 ]
          Todd Lipcon made changes -
          Status Patch Available [ 10002 ] Resolved [ 5 ]
          Hadoop Flags Reviewed [ 10343 ]
          Release Note Committed to branch-2 and trunk.
          Target Version/s
          Fix Version/s 3.0.0 [ 12320356 ]
          Fix Version/s 2.4.0 [ 12326143 ]
          Resolution Fixed [ 1 ]
          Kihwal Lee made changes -
          Link This issue duplicates HDFS-4183 [ HDFS-4183 ]
          Arun C Murthy made changes -
          Status Resolved [ 5 ] Closed [ 6 ]
          Allen Wittenauer made changes -
          Fix Version/s 3.0.0 [ 12320356 ]

            People

            • Assignee:
              Todd Lipcon
              Reporter:
              Todd Lipcon
            • Votes:
              0 Vote for this issue
              Watchers:
              8 Start watching this issue

              Dates

              • Created:
                Updated:
                Resolved:

                Development