Uploaded image for project: 'Accumulo'
  1. Accumulo
  2. ACCUMULO-3957

Consider moving off getContentSummary in the monitor

    XMLWordPrintableJSON

    Details

    • Type: Bug
    • Status: Resolved
    • Priority: Critical
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 1.8.0
    • Component/s: monitor
    • Labels:
      None

      Description

      Recently heard about an issue where a large Hadoop installation which had Accumulo running was experiencing long pauses in the Namenode. Inspecting NN audit logs, it was found that the user running Accumulo issues a getContentSummary("/") call just before the NN pauses were experienced.

      In DefaultServlet.java, we use this call to compute the total HDFS disk usage and present a ratio of space that Accumulo uses relative to the total available space.

      It's still unclear why this was causing issues in this case (as this operation should only be acquiring a read-lock in the namenode), it was recommended to me that Accumulo use the JMX metrics for the NN instead of making this call.

        Attachments

          Issue Links

            Activity

              People

              • Assignee:
                elserj Josh Elser
                Reporter:
                elserj Josh Elser
              • Votes:
                0 Vote for this issue
                Watchers:
                1 Start watching this issue

                Dates

                • Created:
                  Updated:
                  Resolved:

                  Time Tracking

                  Estimated:
                  Original Estimate - Not Specified
                  Not Specified
                  Remaining:
                  Remaining Estimate - 0h
                  0h
                  Logged:
                  Time Spent - 20m
                  20m