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  1. Cassandra
  2. CASSANDRA-8340

Use sstable min timestamp when deciding if an sstable should be included in DTCS compactions

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Details

    • Improvement
    • Status: Resolved
    • Low
    • Resolution: Won't Fix
    • None
    • None

    Description

      Currently we check how old the newest data (max timestamp) in an sstable is when we check if it should be compacted.

      If we instead switch to using min timestamp for this we have a pretty clean migration path from STCS/LCS to DTCS.

      My thinking is that before migrating, the user does a major compaction, which creates a huge sstable containing all data, with min timestamp very far back in time, then switching to DTCS, we will have a big sstable that we never compact (ie, min timestamp of this big sstable is before max_sstable_age_days), and all newer data will be after that, and that new data will be properly compacted

      WDYT Bj0rn ?

      Attachments

        1. 8340.diff
          9 kB
          Jeff Jirsa
        2. 8340-v2.diff
          9 kB
          Jeff Jirsa

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            Unassigned Unassigned
            marcuse Marcus Eriksson
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            Dates

              Created:
              Updated:
              Resolved: