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  1. Cassandra
  2. CASSANDRA-2494

Quorum reads are not monotonically consistent

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Details

    • Bug
    • Status: Resolved
    • Low
    • Resolution: Fixed
    • 1.0.0
    • None
    • None
    • Low

    Description

      As discussed in this thread,

      http://www.mail-archive.com/user@cassandra.apache.org/msg12421.html

      Quorum reads should be consistent. Assume we have a cluster of 3 nodes (X,Y,Z) and a replication factor of 3. If a write of N is committed to X, but not Y and Z, then a read from X should not return N unless the read is committed to at least two nodes. To ensure this, a read from X should wait for an ack of the read repair write from either Y or Z before returning.

      Are there system tests for cassandra? If so, there should be a test similar to the original post in the email thread. One thread should write 1,2,3... at consistency level ONE. Another thread should read at consistency level QUORUM from a random host, and verify that each read is >= the last read.

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        1. 2494-v2.txt
          22 kB
          Jonathan Ellis
        2. 2494.txt
          6 kB
          Jonathan Ellis

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            jbellis Jonathan Ellis Assign to me
            sbridges Sean Bridges
            Jonathan Ellis
            Sylvain Lebresne
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