Uploaded image for project: 'Software Support'
  1. Software Support
  2. SUP-167

gribapi patch to speed up encoding on IBM P6/7

XMLWordPrintable

    • Icon: Improvement Improvement
    • Resolution: Fixed
    • Icon: Major Major
    • GRIB
    • Academic

      Hi Daniel,

      Please can you take a look at and evaluate the attached patch for
      grib_api provided by MPI Hamburg.

      My understanding is that the patch replaces the grib_api encoding engine
      with a C version of that used in GRIBEX developed at MPI Hamburg. This
      allows for separation of integer and floating point operations and a
      more efficient use of the P6 (and P7) pipelines. They claim to see a
      factor o4 4x speed up for encoding on P6 and ~2x on P7.

      Also, please can you send a "contributors' licence" to Uwe Schulzweida
      <uwe.schulzweida@zmaw.de> and Luis Kornblueh <luis.kornblueh@zmaw.de>.

      Thanks

      Paul

      -------- Original Message --------
      Subject: gribapi patch
      Date: Wed, 09 May 2012 14:27:25 +0200
      From: Uwe Schulzweida <uwe.schulzweida@zmaw.de>
      To: Paul.Dando@ecmwf.int
      CC: Luis Kornblueh <luis.kornblueh@zmaw.de>

      Hi Paul,

      Please find attached a performance patch for GRIB_API version 1.9.16.
      With this patch the GRIB2 encoding is a factor of 4 faster on our IBM.
      The changes can be activated with the preprocessor directive: USE_CGRIBEX

      Best regards,
      Uwe

            usv Daniel Varela Santoalla
            usd Paul Dando
            Votes:
            0 Vote for this issue
            Watchers:
            1 Start watching this issue

              Created:
              Updated:
              Resolved: