[molpro-user] Molpro performance on opteron

[H. -J. Werner]

Performance numbers for opteron 2.0 GHZ ifc/i4 serial and parallel (2 processors
only) can be found under www.molpro.net (click benchmarks). On the
average, the Operon 2.0 GHZ ifc/i4 is the fastest of all currently
tested machines for single-processor, 2-processor mpp, and 2 processor 
throughput (2 identical jobs at the same time). The 2.0 GHZ version
used atlas blas built for this machine. But using the prebuilt 
Linux_ATHLON Atlas blas is only slightly slower.
ACML performes much less well than Atlas since it is slow for small
matrices. For the i8 version, compiled with pgf90, the
prebuilt Linux_HAMMER64SSE2_2 performes well, but the overall
performance is worse than for ifc/i4 due to less good optimization of
pgf90. The Portland compiler people told us that this will
be improved in the near future.
Joachim Werner

P.S. There is one unresolved problem with the atlas blas/lapack (i4 version):
the dsyev diagonalization routine crashes on opteron (only for large matrices). 
This problem can be avoided by adding "olddiag2" to the FTCFLAGS in CONFIG:
FTCFLAGS="blas1 blas2 blas3 lapack olddiag2"
After doing this, delete src/util.o and remake the program.


----- Forwarded message from Alex Brown <alex.brown at ualberta.ca> -----

From: Alex Brown <alex.brown at ualberta.ca>
To: Matt Hodges <matt at stchem.bham.ac.uk>
Cc: molpro-user at molpro.net
Subject: Re: Molpro on opteron
Date: 10 Sep 2003 08:32:52 -0600
Message-Id: <1063204372.19791.11.camel at brown.chem.ualberta.ca>
X-Mailer: Ximian Evolution 1.2.2 (1.2.2-5) 
Organization: 

Dear All (and Matt in particular),

  The news/update on the port to the Opteron is very useful. Thanks.

You mention that the ATLAS libraries perform significantly better than
the ACML ones, but can you give an indication of the overall performance
of Molpro on the Opteron. Of course, one would have the advantage of
both 32-bit and 64-bit computing, but it would be nice to have an idea
of how the Opteron is benchmarking against other systems (even at this
early stage before the port is complete).

I have been thinking about the Opteron and news that performance (even
now) is good, may encourage me to leap in anticipation of even better
performance in the future. Any info would be useful.

Cheers,
Alex

On Wed, 2003-09-10 at 03:37, Matt Hodges wrote:
> >>>>> M D Wheeler writes:
> 
>  > Does anyone know if Molpro has been compiled on an opteron system??
>  > If not, does anyone know if it is possible??
> 
> The Opteron port is work in progress. There is a patch for 2002.6 that
> contains changes to the configure process to support such systems, and
> licence objects for i4 and i8. At the moment, the i4 version works
> well (all testjobs succeed), and we have found that performance with
> the ATLAS libraries is significantly better than with the ACML ones
> (<URL:http://developer.amd.com>).
> 
> With all patches applied, it should be possible to configure the i4
> version of Molpro 2002.6 by first making sure that the 32-bit compiler
> is in your path (i.e., 'which pgf90' should return something like
> /usr/pgi/linux86/5.0/bin/pgf90), then using './configure -pgf90'.
> 
> Note that there are some unresolved problems with the i8 version, and
> all the above is for serial execution; we don't yet have a version
> working with Global Arrays on this platform.
-- 
Alex Brown
Assistant Professor                
Department of Chemistry      
University of Alberta                 
Edmonton, AB
T6G 2G2
http://www.chem.ualberta.ca/~abrown/


----- End forwarded message -----

-- 
Prof. Hans-Joachim Werner
Institute for Theoretical Chemistry
University of Stuttgart
Pfaffenwaldring 55
D-70569 Stuttgart, Germany
Tel.: (0049) 711 / 685 4400
Fax.: (0049) 711 / 685 4442
e-mail: werner at theochem.uni-stuttgart.de