Re: [AMBER-Developers] potential optimisation problem in qm2_get_qm_forces

From: Andreas Goetz <>
Date: Mon, 1 Mar 2010 13:34:11 -0800

Hi Ben,

This will only affect performance. A change of the QM gradient routines would require major rewrites which we can't do right now (but should do eventually). So, no, this does not represent a problem.

As a note aside: I have been cleaning up the QM energy routines wrt the core core repulsion (to get the PM6 terms in). Same is happening now for the gradient routines (but this is only a rather small part). Eventually, larger cleanups will happen for the implementation of d orbitals (not for the upcoming release).

All the best,

On Mar 1, 2010, at 1:21 PM, Ben Roberts wrote:

> Again, compiling with ifort -check, I get a complaint from the qm/mm parts of the code:
> ifort -check -c -ip -O3 -xHost -axSSE4.1,SSSE3 -FR -o qm2_get_qm_forces.o _qm2_get_qm_forces.f
> Space exceeded in Data Dependence Test in _qm2_deriv_qm_analyt_
> Subdivide routine into smaller ones to avoid optimization loss
> An internal threshold was exceeded for routine _qm2_deriv_qm_analyt_ and optimization level may be reduced. See HTTP://SOFTWARE.INTEL.COM/EN-US/ARTICLES/INTERNAL-THRESHOLD-WAS-EXCEEDED for more information and advice.
> Does this represent a problem (even if just at the efficiency level)?
> Cheers,
> Ben
> _______________________________________________
> AMBER-Developers mailing list

Dr. Andreas W. Goetz
San Diego Supercomputer Center
Tel  : +1-858-822-4771
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Received on Mon Mar 01 2010 - 14:00:02 PST
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