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  1. Cassandra
  2. CASSANDRA-7272

Add "Major" Compaction to LCS and split sstables during STCS major compaction

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Details

    • Improvement
    • Status: Resolved
    • Low
    • Resolution: Fixed
    • 2.2.0 beta 1
    • None
    • Docs

    Description

      LCS has a number of minor issues (maybe major depending on your perspective).

      LCS is primarily used for wide rows so for instance when you repair data in LCS you end up with a copy of an entire repaired row in L0. Over time if you repair you end up with multiple copies of a row in L0 - L5. This can make predicting disk usage confusing.

      Another issue is cleaning up tombstoned data. If a tombstone lives in level 1 and data for the cell lives in level 5 the data will not be reclaimed from disk until the tombstone reaches level 5.

      I propose we add a "major" compaction for LCS that forces consolidation of data to level 5 to address these.

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              marcuse Marcus Eriksson
              tjake T Jake Luciani
              Marcus Eriksson
              Carl Yeksigian
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                Updated:
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