[Beowulf] fftw2, mpi, from 32 bit to 64 and fortran

Mark Kosmowski mark.kosmowski at gmail.com
Fri Aug 1 12:45:07 PDT 2008

> Message: 3
> Date: Fri, 1 Aug 2008 14:23:13 -0400 (EDT)
> From: Mark Hahn <hahn at mcmaster.ca>
> Subject: Re: [Beowulf] fftw2, mpi, from 32 bit to 64 and fortran
> To: Ricardo Reis <rreis at aero.ist.utl.pt>
> Cc: beowulf at beowulf.org
> Message-ID:
>        <Pine.LNX.4.64.0808011420160.18571 at coffee.psychology.mcmaster.ca>
> Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed
> > I've scourged the net for answers to no avail and the fftw project seems to
> > have grinded to a halt. Maybe someone has had this problem and can throw some
> > light.
> I don't know the status of the project, but fftw is definitely still
> widely used, and definitely works in 64b.
> > I've coded a small program that reads a vorticity field, uses FFTW2 to send
> > it from the physical to the spectral space and then computes its energy
> > spectrum. Everything works in my laptop (32 bit, Linux), serial, threaded and
> > mpi (using openmpi). In a 64 bit machine the mpi version kaputs. Any
> > thoughts?
> 32-64 problems usually stem from someone conflating ints and pointers.
> we have fftw2 installed on all our machines, which are all 64b (for years).
> no reports of problems.
> did you compile your own fftw2, and if so, did you run the test cases?

What exactly is going wrong?  Is your program failing to link or does
it die during execution?

Have you built 64-bit versions of fftw and mpi libraries?  Are you
positive that you've changed from 32-bit to 64-bit all of the
libraries your code links to, even the ones not related to fftw or

You imply that 64-bit serial with fftw works - are you able to get a
different code to run with 64-bit mpi?

Good luck,

Mark Kosmowski

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