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  1. Cassandra
  2. CASSANDRA-2006

Serverwide caps on memtable thresholds

    Details

    • Type: Improvement
    • Status: Resolved
    • Priority: Major
    • Resolution: Fixed
    • Fix Version/s: 0.8 beta 1
    • Component/s: None
    • Labels:
      None

      Description

      By storing global operation and throughput thresholds, we could eliminate the "many small memtables" problem caused by having many CFs. The global threshold would be set in the config file, to allow different classes of servers to have different values configured.

      Operations occurring in the memtable would add to the global counters, in addition to the memtable-local counters. When a global threshold was violated, the memtable in the system that was using the largest fraction of it's local threshold would be flushed. Local thresholds would continue to act as they always have.

      The result would be larger sstables, safer operation with multiple CFs and per node tuning.

        Attachments

        1. 2006-v3.txt
          27 kB
          Jonathan Ellis
        2. 2006-v2.txt
          26 kB
          Jonathan Ellis
        3. jamm-0.2.jar
          6 kB
          Jonathan Ellis
        4. 2006.txt
          22 kB
          Jonathan Ellis

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              • Assignee:
                jbellis Jonathan Ellis
                Reporter:
                stuhood Stu Hood
                Reviewer:
                Stu Hood
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                Dates

                • Created:
                  Updated:
                  Resolved: