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Subject: Re: [OMPI users] MPI-IO puzzlement
From: Ricardo Reis (rreis_at_[hidden])
Date: 2012-05-15 04:28:39


  Hi all

  The problem has been found.

  I'm trying to use MPI-IO to write the file with all processes taking part
in the calculation writing their bit. Here lies the rub.

  Each process has to write a piece of DIM = 35709696 elements.

  Using 64 processes the ofsett is my_rank * dim

  and so... the ofset size, for last processes becomes.

  DBG: 60 will WriteMPI_IO. dim 35709696 offset 2142581760
  DBG: 61 will WriteMPI_IO. dim 35709696 offset -2116675840
  DBG: 62 will WriteMPI_IO. dim 35709696 offset -2080966144
  DBG: 63 will WriteMPI_IO. dim 35709696 offset -2045256448

  offset is of the type MPI_OFFSET_KIND which seems insuficient to hold the
correct size for the offset.

  So... am I condemned to write my own MPI data type so I can write the
files? ideas... ?

  best regards,

  Ricardo Reis

  'Non Serviam'

  PhD/MSc Mechanical Engineering | Lic. Aerospace Engineering

  Computational Fluid Dynamics, High Performance Computing, Turbulence
  http://www.lasef.ist.utl.pt

  Cultural Instigator @ Rádio Zero
  http://www.radiozero.pt

  http://www.flickr.com/photos/rreis/

  contacts: gtalk: kyriusan_at_[hidden] skype: kyriusan

  Institutional Address:

  Ricardo J.N. dos Reis
  IDMEC, Instituto Superior Técnico, Technical University of Lisbon
  Av. Rovisco Pais
  1049-001 Lisboa
  Portugal

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