Re: AMBER: running on Itanium machines

From: David A. Case <>
Date: Fri, 9 Jan 2004 08:43:48 -0800

On Thu, Jan 08, 2004, wrote:
> Has anyone had trouble running simulations on Itanium machines using Intel
> compilers? I have a number of simulations that don't run correctly on our
> Intel IA64 cluster. They run fine on our local IA32 cluster, but when run
> on the IA64 I've noticed the following problems: Jobs run in implicit
> solvent don't output any energy information. Instead, in the output file,
> the energy and temperature terms are all just question marks. Jobs run in
> explicit solvent result in wildly fluctuating potential energies. The
> potential energy terms (when using constant volume or constant pressure)
> fluctuate by thousands of Kcal. The same jobs run on our local cluster
> fluctuate by less than 10 kcal.

We need more information about what OS, which version of the compilers you are
using, and what compiler options you used. I would suggest compiling with
lower optimization (definitely not -O3), if you have not already tried that.
Various versions of efc (aka ifort) have failed to compile amber correctly
with -O3 set.

(Amber does work on some[many] IA64 machines using Intel compilers; which is
why we need more info.)

...hope this helps...dac

David A. Case                     |  e-mail:
Dept. of Molecular Biology, TPC15 |  fax:          +1-858-784-8896
The Scripps Research Institute    |  phone:        +1-858-784-9768
10550 N. Torrey Pines Rd.         |  home page:                   
La Jolla CA 92037  USA            |
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Received on Wed Jan 14 2004 - 15:53:15 PST
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