Uploaded image for project: 'Hadoop HDFS'
  1. Hadoop HDFS
  2. HDFS-2126 Improve Namenode startup time [umbrella task]
  3. HDFS-1295

Improve namenode restart times by short-circuiting the first block reports from datanodes

    Details

    • Type: Sub-task
    • Status: Resolved
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: 0.23.0
    • Fix Version/s: Federation Branch, 0.23.0
    • Component/s: namenode
    • Labels:
      None
    • Hadoop Flags:
      Reviewed

      Description

      The namenode restart is dominated by the performance of processing block reports. On a 2000 node cluster with 90 million blocks, block report processing takes 30 to 40 minutes. The namenode "diffs" the contents of the incoming block report with the contents of the blocks map, and then applies these diffs to the blocksMap, but in reality there is no need to compute the "diff" because this is the first block report from the datanode.

      This code change improves block report processing time by 300%.

        Attachments

        1. shortCircuitBlockReport_1.txt
          10 kB
          dhruba borthakur
        2. IBR_shortcut_v2a.patch
          29 kB
          Matt Foley
        3. IBR_shortcut_v3atrunk.patch
          28 kB
          Matt Foley
        4. IBR_shortcut_v4atrunk.patch
          49 kB
          Matt Foley
        5. IBR_shortcut_v4atrunk.patch
          49 kB
          Matt Foley
        6. IBR_shortcut_v4atrunk.patch
          49 kB
          Matt Foley
        7. IBR_shortcut_v6atrunk.patch
          49 kB
          Matt Foley
        8. IBR_shortcut_v7atrunk.patch
          33 kB
          Matt Foley
        9. HDFS-1295_delta_for_trunk.patch
          2 kB
          Matt Foley
        10. HDFS-1295_for_ymerge.patch
          32 kB
          Matt Foley
        11. HDFS-1295_for_ymerge_v2.patch
          33 kB
          Matt Foley

          Issue Links

            Activity

              People

              • Assignee:
                mattf Matt Foley
                Reporter:
                dhruba dhruba borthakur
              • Votes:
                0 Vote for this issue
                Watchers:
                14 Start watching this issue

                Dates

                • Created:
                  Updated:
                  Resolved: