Hadoop Map/Reduce
  1. Hadoop Map/Reduce
  2. MAPREDUCE-1829

JobInProgress.findSpeculativeTask should use min() to find the candidate instead of sort()

    Details

    • Type: Improvement Improvement
    • Status: Closed
    • Priority: Major Major
    • Resolution: Fixed
    • Affects Version/s: 0.22.0
    • Fix Version/s: 0.22.0
    • Component/s: jobtracker
    • Labels:
      None
    • Hadoop Flags:
      Reviewed
    • Release Note:
      Improved performance of the method JobInProgress.findSpeculativeTask() which is in the critical heartbeat code path.

      Description

      findSpeculativeTask needs only one candidate to speculate so it does not need to sort the whole list. It may looks OK but someone can still submit big jobs with small slow task thresholds. In this case, this sorting becomes expensive.

      1. MAPREDUCE-1829.txt
        1 kB
        Scott Chen
      2. MAPREDUCE-1829-20100610.txt
        3 kB
        Vinod Kumar Vavilapalli

        Activity

          People

          • Assignee:
            Scott Chen
            Reporter:
            Scott Chen
          • Votes:
            0 Vote for this issue
            Watchers:
            3 Start watching this issue

            Dates

            • Created:
              Updated:
              Resolved:

              Development