Subject: Summary: Speed of new HP and SGI workstations

From: Steen Hammerum <[email-masked]>
Date: Fri, 23 Aug 1996 21:49:19 +0200 (METDST)

Summary: Speed of new HP and SGI workstations

I recently asked this group for advice with regard to the performance
of new HP and SGI workstations running the Gaussian programs

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Does anyone have or know of benchmarks for Gaussian 94 or related programs
running on the new SGI and HP chips (R10000 and PA8000), or other
information to assist us before we decide on new machinery?

We are currently considering SGI Power Indigo 2 and HP C160 workstations
that will be used predominantly for Gaussian calculations, but we are not
sure how well the SPECint95 and SPECfp95 numbers allow us to assess the
relative performance.

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There weren't very many answers, and in particular, no-one came forward with
results obtained with the new HP PA8000 machines.

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Roberto Gomperts ([email-masked]) provided the following comparison
of the SGI R8000 and R10000 chips when running test178 from the Gaussian 94
test suite (a single point, direct scf calculation with 300 basis
functions), using Gaussian 94, rev. D3.

   Machine	  Chip/Frequency	Sec. Cache	Time(min.)
Power Indigo2	   r8k/75 MHz		  2 MB		  8.04
Power Challenge	   r8k/90 MHz		  4 MB		  6.50
Power Indigo2     r10k/195 MHz		  1 MB		  7.30
Power Challenge	  r10k/195 MHz	          1 MB		  7.08
Power Challenge	  r10k/195 MHz		  2 MB		  5.95

The Power Challenge runs are done on 1 processor.  These are all CPU times. 
The Wall clock times are very similar to these (less than 20 sec. difference)

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John Brodholt ([email-masked]) pointed me to

http://gserv1.dl.ac.uk/TCSC/disco/TechPapers/bench/bench.html

This site provides a detailed, critical and very useful comparison of the
performance of a wide variety of newer workstations; unfortunately, no
results obtained with HP PA8000 machines are included (html version not yet
available, but a postscript version can be downloaded).  The comparison is
based on timing data obtained with GAMESS-UK (rather than Gaussian).  The
results illustrate that the relative performance varies quite a bit with
the type of calculation undertaken.

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Eric Billings ([email-masked]) pointed me to

http://www.ki.si/parallel/summary.html

The information was designed to compare parallel architectures, but the 
single CPU column provides useful information.

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Finally, Glenn McEnroe ([email-masked]) suggested that I looked elsewhere:

"Regarding your question about SGI vs HP you should check out the latest
issue of Journal of Computational Chem V17 No. 11 1385-86 entitled
Viability of Molecular Modeling with Pentium based PCs. This article does
not compare these new chips for SGI and HP but it appears that you may be
better off running your application on a pentium based machine if Gaussian
94 is available for this platform."

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Many thanks to everyone who answered.

Steen
-- 
	
Steen Hammerum                                           [email-masked]
Department of Chemistry                              (+45) 35 32 02 08
University of Copenhagen, Denmark               fax: (+45) 35 32 02 12