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  1. Cassandra
  2. CASSANDRA-1096

Sequential splits causing unbalanced MapReduce load

    Details

    • Type: Improvement
    • Status: Resolved
    • Priority: Minor
    • Resolution: Fixed
    • Fix Version/s: 0.6.2
    • Component/s: None
    • Labels:

      Description

      Since CassandraInputFormat returns an ordered list of splits, when there are many splits (e.g. hundreds or more) the load on cassandra is horribly unbalanced. e.g. if I have 30 tasks processing 600 splits, then the rows for the first 30 splits are all located on the same one or two nodes.

        Attachments

        1. CASSANDRA-1096.patch
          0.5 kB
          Joost Ouwerkerk

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            People

            • Assignee:
              joosto Joost Ouwerkerk
              Reporter:
              joosto Joost Ouwerkerk
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