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  1. Cassandra
  2. CASSANDRA-12922

Bloom filter miss counts are not measured correctly

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      Description

      Bloom filter hits and misses are evaluated incorrectly in BigTableReader.getPosition: we properly record hits, but not misses. In particular, if we don't find a match for a key in the index, which is where almost all non-matches will be rejected, we don't record a bloom filter false positive.

      This leads to very misleading output from e.g. nodetool tablestats.

        Attachments

        1. cassandra-12922-trunk.txt
          17 kB
          Aleksei Zotov
        2. cassandra-12922-4.0.txt
          17 kB
          Aleksei Zotov
        3. cassandra-12922-3.11.txt
          15 kB
          Aleksei Zotov
        4. cassandra-12922-3.0.txt
          15 kB
          Aleksei Zotov
        5. 12922-trunk.txt
          1 kB
          Sundar Srinivasan

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            • Assignee:
              azotcsit Aleksei Zotov
              Reporter:
              blambov Branimir Lambov
              Authors:
              Aleksei Zotov
              Reviewers:
              Benjamin Lerer, Branimir Lambov
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                Updated:
                Resolved:

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