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  1. Derby
  2. DERBY-959

Allow use of DRDA QRYDTA block sizes greater than 32K

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Details

    • Improvement
    • Status: Closed
    • Minor
    • Resolution: Fixed
    • 10.1.1.0, 10.1.2.1, 10.2.1.6
    • 10.2.1.6
    • None
    • Performance

    Description

      Currently, the Network Server and Network Client use a 32K blocksize when
      returning database data in QRYDTA blocks.

      I came across the following statement in the DRDA spec (Volume 1, page 12):

      Blocking applies only to the QRYDTA reply objects. Each
      query block is a QRYDTA DSS. The maximum query block size
      value allowed in the qryblksz parameter is increased from
      32K to 10M, thus accomodating the larger data volumes
      required by modern, more data-intensive applications.

      The importance of larger block sizes depends strong on the application
      profile.. For example, many applications perform single-record selects,
      and they are not influenced by the block size.

      But for some applications, it seems like the ability to use a larger block
      size could be quite valuable.

      Attachments

        1. SmallRows_64kBlkSz.trace
          394 kB
          Sunitha Kambhampati
        2. SmallRows_32kBlkSz.trace
          395 kB
          Sunitha Kambhampati
        3. odbc_rowgreaterthan64k.trace
          1.44 MB
          Sunitha Kambhampati
        4. derby959.review.stat.txt
          0.4 kB
          Sunitha Kambhampati
        5. derby959.review.diff.txt
          6 kB
          Sunitha Kambhampati
        6. 959Notes_v1.html
          17 kB
          Sunitha Kambhampati

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              skambha Sunitha Kambhampati
              bryanpendleton Bryan Pendleton
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              Dates

                Created:
                Updated:
                Resolved: