[petsc-users] Number of nonzeros > 2^31-1

[Matthew Knepley]

On Tue, Jul 17, 2012 at 6:20 AM, Nicolas TARDIEU <nicolas.tardieu at edf.fr>wrote:

>
> Dear PETSc users,
>
> I am solving an unstructured finite element-based problem with 500
> millions unkwowns with PETSc.
> The number of nonzeros is greater than 2^31-1.
> Here is the KSPView I get :
>
> ----------------------------------------------------------------------------------------------------------------
>   Matrix Object:   700 MPI processes
>     type: mpiaij
>     rows=499125000, cols=499125000
>     total: nonzeros=-2147483648, allocated nonzeros=-2147483648
>     total number of mallocs used during MatSetValues calls =0
>       using I-node (on process 0) routines: found 242923 nodes, limit used
> is 5
>
> ----------------------------------------------------------------------------------------------------------------
>
> As you can see, The number of nonzeros is <0.
> I would like to check that this is due to the number of nonzeros being
> greater than 2^31-1.
>
> Here is a short description of the size of differents types :
>
> ----------------------------------------------------------------------------------------------------------------
> Compiled with full precision matrices (default)
> sizeof(short) 2 sizeof(int) 4 sizeof(long) 8 sizeof(void*) 8
> sizeof(PetscScalar) 8
>
> ----------------------------------------------------------------------------------------------------------------
>
> Is there a workaround? Should I worry about the result of my simulation?
>

You could configure using --with-64-bit-indices.

    Matt


> Thanks in advance,
> Nicolas      *Nicolas TARDIEU**
> Ing. Chercheur*
> EDF - R&D Dpt AMA
>
> *nicolas.tardieu at edf.fr*
> Tél. : 01 47 65 39 05   Un geste simple pour l'environnement, n'imprimez
> ce message que si vous en avez l'utilité.
>
>
> Ce message et toutes les pièces jointes (ci-après le 'Message') sont
> établis à l'intention exclusive des destinataires et les informations qui y
> figurent sont strictement confidentielles. Toute utilisation de ce Message
> non conforme à sa destination, toute diffusion ou toute publication totale
> ou partielle, est interdite sauf autorisation expresse.
>
> Si vous n'êtes pas le destinataire de ce Message, il vous est interdit de
> le copier, de le faire suivre, de le divulguer ou d'en utiliser tout ou
> partie. Si vous avez reçu ce Message par erreur, merci de le supprimer de
> votre système, ainsi que toutes ses copies, et de n'en garder aucune trace
> sur quelque support que ce soit. Nous vous remercions également d'en
> avertir immédiatement l'expéditeur par retour du message.
>
> Il est impossible de garantir que les communications par messagerie
> électronique arrivent en temps utile, sont sécurisées ou dénuées de toute
> erreur ou virus.
> ____________________________________________________
>
> This message and any attachments (the 'Message') are intended solely for
> the addressees. The information contained in this Message is confidential.
> Any use of information contained in this Message not in accord with its
> purpose, any dissemination or disclosure, either whole or partial, is
> prohibited except formal approval.
>
> If you are not the addressee, you may not copy, forward, disclose or use
> any part of it. If you have received this message in error, please delete
> it and all copies from your system and notify the sender immediately by
> return message.
>
> E-mail communication cannot be guaranteed to be timely secure, error or
> virus-free.
>



-- 
What most experimenters take for granted before they begin their
experiments is infinitely more interesting than any results to which their
experiments lead.
-- Norbert Wiener
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120717/311fe8b8/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/gif
Size: 1151 bytes
Desc: not available
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120717/311fe8b8/attachment-0002.gif>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/gif
Size: 1816 bytes
Desc: not available
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120717/311fe8b8/attachment-0003.gif>