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  1. Cassandra
  2. CASSANDRA-3234

LeveledCompaction has several performance problems

    Details

    • Type: Bug
    • Status: Resolved
    • Priority: Normal
    • Resolution: Fixed
    • Fix Version/s: 1.0.0
    • Component/s: None
    • Labels:
    • Severity:
      Normal

      Description

      Two main problems:

      • BF size calculation doesn't take into account LCS breaking the output apart into "bite sized" sstables, so memory use is much higher than predicted
      • ManyToMany merging is slow. At least part of this is from running the full reducer machinery against single input sources, which can be optimized away.

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            • Assignee:
              jbellis Jonathan Ellis
              Reporter:
              jbellis Jonathan Ellis
              Authors:
              Jonathan Ellis
              Reviewers:
              Brandon Williams
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              Dates

              • Created:
                Updated:
                Resolved: