Uploaded image for project: 'Lucene - Core'
  1. Lucene - Core
  2. LUCENE-1125

Excessive Arrays.fill(0) in DocumentsWriter drastically slows down small docs (3.9X slowdown!)

    XMLWordPrintableJSON

Details

    • Bug
    • Status: Closed
    • Major
    • Resolution: Fixed
    • 2.3
    • 2.3
    • core/index
    • None
    • New

    Description

      I've been doing some "final" performance testing of 2.3RC1 and
      uncovered a fairly serious bug that adds a large fixed CPU cost when
      documents have any term vector enabled fields.

      The bug does not affect correctness, just performance.

      Basically, for every document, we were calling Arrays.fill(0) on a
      large (32 KB) byte array when in fact we only needed to zero a small
      part of it. This only happens if term vectors are turned on, and is
      especially devastating for small documents.

      Attachments

        1. LUCENE-1125.patch
          2 kB
          Michael McCandless

        Activity

          People

            mikemccand Michael McCandless
            mikemccand Michael McCandless
            Votes:
            0 Vote for this issue
            Watchers:
            1 Start watching this issue

            Dates

              Created:
              Updated:
              Resolved: