[gmx-developers] Coulomb LR energy totals on AMD???

[Anton Feenstra]

David van der Spoel wrote:
> On Tue, 2003-09-09 at 16:06, Anton Feenstra wrote:
> 
> If it is amd only, then I presume that it has to be in one of either
> PME, fftw or the ewald corrections. If you say it is reproducible do you
> mean that you get the same weird result with the same run repeatedly?

No, similar results in many different runs, i.e. not simulation system
dependent (but all protein + heme + ligand + water, as far as I've
checked). But, this is without PME or ewald...

It's 3Dnow only, because on our newer AMD, where SSE is used, the error
disappears.

> The line of testing should be first to turn off assembly in compiling
> (this will also turn off some other assembly bits in pme.c), then, if
> the error persists use CFLAGS=-g, a further option could be to upgrade
> your fftw (2.1.5) or to compile fftw without the i386 hacks..

Isn't there an envvar to disable assembly loops runtime?


-- 
Groetjes,

Anton
  _____________ _______________________________________________________
|             |                                                       |
|  _   _  ___,| K. Anton Feenstra                                     |
| / \ / \'| | | Dept. of Pharmacochem. - Vrije Universiteit Amsterdam |
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