[DFTB-Plus-User] On parallel version of DFTB+
benjamin.hourahine at strath.ac.uk
Mon Sep 12 09:26:34 CEST 2016
just to add to Bálint's comments, setting
WriteHSDInput = No
will prevent the code from trying to write the dftb_pin.hsd file which
is where MAXRECL causes problems.
As Bálint mentions, errors usually indicate atoms too close together,
but the pdpotrf routine in some versions of ScaLAPACK can be a little
temperamental. If you cannot find an obvious problem with the atom
coordinates, is there an alternative version of the library installed
that you can try?
On 12/09/16 07:50, Bálint Aradi wrote:
> Dear ZhaoHui Huang,
>> I have an issue from running parallel DFTB+. My unit cell contains
>> 26,000 atoms and I just want to relax the structures a few steps. By
>> running the code, I first get output overflow error message, then I
>> increase MAXRECL parameter defined in HSDParser package. It runs
>> indeed. but It failed by SCALAPACK error,
> Yes, correct, this MAXRECL just comes from the fact, that we write out
> the coordinates with one write statement, which at those system sizes
> can be unfortunately problematic (depending on the compiler).
>> MAXNEIGHBORS: 8847 iSCC Total electronic Diff electronic SCC
>> error Operation failed! ppotrf in scalafx_ppotrf_dreal Info: 23233
>> Is there any code developer who is familiar with this part of code?
> ppotrf is the wrapper around the pdpotrf routine in ScaLAPACK, which
> does the Cholesky-decomposition. When it fails, it is often an
> indication, that your overlap matrix is ill defined. Maybe some atoms
> are unphysically close to each other (eventually due to periodic
> boundary conditions)?. Can you somehow check, how close the atoms are to
> each other. You may do it by analyzing the first few elements of the
> iNeighbors(0:,1:nAtom) array. The first index goes over the neighbors of
> a given atom (second index). It is never printed out anywhere, but it
> should tell you when something is fishy.
> Best regards,
> DFTB-Plus-User mailing list
> DFTB-Plus-User at mailman.zfn.uni-bremen.de
Dr. B. Hourahine, SUPA, Department of Physics,
University of Strathclyde, John Anderson Building,
107 Rottenrow, Glasgow G4 0NG, UK.
+44 141 548 2325, benjamin.hourahine at strath.ac.uk
2013/14 THE Awards Entrepreneurial University of the Year
2012/13 THE Awards UK University of the Year
The University of Strathclyde is a charitable body,
registered in Scotland, number SC015263
More information about the DFTB-Plus-User