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  1. ROOT
  2. ROOT-8871 Improve performance of ROOT I/O
  3. ROOT-8872

Improve performance of TTree::Fill();

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Details

    • Sub-task
    • Status: Closed (View Workflow)
    • High
    • Resolution: Fixed
    • None
    • 6.12/00
    • None
    • None

    Description

      TTree::Fill() is a hotspot in the random number generation benchmark due to the condition checking if an auto-save or auto-flush action must be performed. Both checks use a "fEntries % N == 0" operation, which is as expensive as a division. This expensive operation can be replaced by a check for equality if we use a counter that is reset every time an auto-flush or auto-save is performed.

      Attachments

        1. autoflush.png
          autoflush.png
          362 kB
        2. hotspots.png
          hotspots.png
          83 kB
        3. ttree-fill-ge-diff.png
          ttree-fill-ge-diff.png
          35 kB
        4. ttree-fill-ge-timediff.png
          ttree-fill-ge-timediff.png
          159 kB

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            amadio Guilherme Amadio
            amadio Guilherme Amadio
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              Updated:
              Resolved:
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