Hadoop Common
  1. Hadoop Common
  2. HADOOP-5494

IFile.Reader should have a nextRawKey/nextRawValue

    Details

    • Type: Improvement Improvement
    • Status: Closed
    • Priority: Major Major
    • Resolution: Fixed
    • Affects Version/s: 0.18.0
    • Fix Version/s: 0.21.0
    • Component/s: None
    • Labels:
      None
    • Hadoop Flags:
      Reviewed

      Description

      Merger.Segment has only the next() method defined which internally calls next(key,value) on the underlying IFile stream. This would read both the key and the value bytes. It would be good to have Merger.Segment.nextRawKey(), that would read only the key and delay reading the value until needed (in Merger.MergeQueue.next()) via a new method Merger.Segment.nextRawValue().
      This would mean that we load only one value bytes at a time, and hence would incur potentially much less (depending on how big the values are) on the memory footprint.

      1. 5494-1.patch
        13 kB
        Devaraj Das
      2. 5494-2.patch
        14 kB
        Devaraj Das
      3. 5494-3.patch
        15 kB
        Devaraj Das
      4. 5494-4.patch
        15 kB
        Devaraj Das

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            • Assignee:
              Devaraj Das
              Reporter:
              Devaraj Das
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              • Created:
                Updated:
                Resolved:

                Development