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  1. Cassandra
  2. CASSANDRA-646

Fix few minor problems in nodeprobe cfstats

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    Details

    • Type: Bug
    • Status: Resolved
    • Priority: Low
    • Resolution: Fixed
    • Fix Version/s: 0.5
    • Component/s: Legacy/Tools
    • Labels:
      None
    • Severity:
      Low

      Description

      nodeprobe cfstats reports that readlatency/writelatency is NaN on the keyspace level although it obviously is not.

      For example:
      Keyspace: Keyspace1
      Read Count: 392
      Read Latency: NaN ms.
      Write Count: 262
      Write Latency: NaN ms.
      Pending Tasks: 0

      Column Family: MyCF
      Memtable Columns Count: 143
      Memtable Data Size: 123433
      Memtable Switch Count: 2
      Read Count: 392
      Read Latency: 0.533 ms.
      Write Count: 262
      Write Latency: 0.000 ms.
      Pending Tasks: 0

      Column Family: Standard2
      Memtable Columns Count: 0
      Memtable Data Size: 0
      Memtable Switch Count: 0
      Read Count: 0
      Read Latency: NaN ms.
      Write Count: 0
      Write Latency: NaN ms.
      Pending Tasks: 0

      The problem here is that there is more than one cf, and one of them has read latency/writelatency NaN. This causes the keyspace readlatency/writelatency to be NaN instead of the average across all cfs.

      Another problem with cfstats is that it does not account for the delays when a read/write times out, so it does not accurately reflect the health of the system under too much stress.

        Attachments

        1. 646-05.patch
          2 kB
          Jonathan Ellis

          Activity

            People

            • Assignee:
              jbellis Jonathan Ellis
              Reporter:
              rrabah Ramzi Rabah
              Authors:
              Jonathan Ellis
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              Dates

              • Created:
                Updated:
                Resolved: