[DFTB-Plus-User] compile question

[Bálint Aradi]

Dear Mani,

> I have compiled the code using gfortran and the file make.x86_64-linux-gfortran, which produced a serial executable. To get the parallel executable I added -fopenmp switch to the compile and link options. It did compile, but doesn't run, stopping immediately with 'segmentation fault' message. Could anyone give me a hint on compiling with openmp?

 Segfault could have many reasons. One possibility is, your stack size
is limited in the shell, where you execute DFTB+. Try to set it to
unlimited (e.g. 'ulimit -s unlimited' in BASH). Otherwise, it is hard to
say.

  Also, please note, that for middle and large size systems DFTB+ spends
around 95% of the time in the diagonalization. So, the win in OpenMP
parallalization of the DFTB+ code is almost negligible compared to the
linkage of a multithreaded LAPACK/BLAS library.

  In doubt, just use the binaries available on the website.

  Viele Grüße

   Bálint

-- 
Dr. Bálint Aradi
Bremen Center for Computational Materials Science, University of Bremen
http://www.bccms.uni-bremen.de/cms/people/b_aradi/


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