[comp.sys.alliant] FX/2800 PERFORMANCE ON CONVOLUTION

neray@Alliant.COM (Phil Neray) (12/04/90)

figures achieved recently with the FX/2800, with apologies for the
"PR"-ness of the text.

Notes:

- Results are for time domain convolutions.

- The specific performance achieved is 2.15 GFLOPS on a 32-bit
convolution, with filter size of 500 and data length of 50,000,
for an FX/2800 with 28 i860 processors. This corresponds to 96%
of the system's peak theoretical performance, and compares to 
the Cray Y-MP8 published figure of 2.012 GFLOPS.

Smaller FX/2800 configurations have also shown excellent performance.
For example, the 8-processor system achieved 575 MFLOPS on 500 x 20,000, 
compared to the Y-MP8 figure of 546 MFLOPS.

- Other recent performance results for the FX/2800 include 295 MFLOPS on
the LINPACK 1000  (using 14 processors, as published in the current 
Dongarra report).

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ALLIANT FX/2800 SYSTEMS BREAK 2 GFLOPS PERFORMANCE 
          IN SIGNAL PROCESSING ROUTINE
Convolution Frequently Used In Seismic Exploration

LITTLETON, Mass., December 3, 1990 -- Alliant Computer 
Systems Corporation (NASDAQ/ALNT) today announced its FX/2800 
supercomputers have exceeded two billion floating point 
operations a second (2 GFLOPS) on a linear convolution software 
routine frequently used in seismic exploration and in a wide 
range of digital signal processing applications. 

The results are significant because they are achievable on an 
Alliant RISC-based FX/2800 supercomputer that sells for under two 
million dollars.  Normally, these computations are run on a Cray 
Research Y-MP eight processor supercomputer that is priced in 
excess of $15 million. 

The convolution is used to process digital data acquired in a 
wide range of disciplines.  In oil exploration, for example, 
surface explosions cause underground strata to return echoes that 
can be processed, using convolutions, to pinpoint promising 
locations to drill for oil.  In radar and sonar signal 
processing, incoming signals can be filtered using this 
computational technique to eliminate background noise and search 
for specific kinds of targets.  

Other disciplines in which the software is used include 
crystallography, communications, speech recognition and speech 
synthesis, satellite image enhancement, High Definition 
Television (HDTV) research, vibration analysis and weather 
prediction.

"Many applications that use convolutions have enormous data sets 
requiring the throughput capabilities of very expensive 
supercomputers," said John Scanlon, Alliant's vice president of 
marketing.  "The combination of RISC microprocessors and parallel 
processing architecture in the FX/2800 series makes it possible 
to address these requirements with a relatively low-priced 
supercomputer." Alliant has exceeded 2,145 MFLOPS on an FX/2828, 
a system with 28 Intel 860 RISC microprocessors.  This compares 
to Cray Research's published (Cray Channels, Winter, 1990 
edition) figure of 2,012 MFLOPS on a Cray Y-MP eight processor 
model, and the peak theoretical performance of 200 MFLOPS on a 
Convex C240 four-processor system. An Alliant supercomputer 
occupies less than seven square feet of floor space, compared 
with the Cray Y-MP's 98 square feet.  Likewise, the FX/2800 
family uses air cooling, while the Cray unit requires liquid 
cooling.  The convolution routines are supplied as part of 
Alliant's scientific libraries package.  Alliant's scientific 
libraries package is available immediately and is priced at 
$15,000.

"A general purpose supercomputer based on a non-proprietary 
instruction set that delivers this kind of performance at this 
price range is very attractive, compared to the traditional 
supercomputer approach," said Robert Limbaugh, president and 
chief executive officer at GeoQuest Technologies Corp., a seismic 
software and data processing service company.

Alliant Computer Systems Corporation manufactures standards-based 
parallel supercomputers with visualization tools that enable 
scientists and engineers to quickly interpret and solve complex 
problems.
-- 
Phil Neray			Domain:	neray@alliant.com
Alliant Computer Systems	UUCP:	{mit-eddie|linus}!alliant!neray
Littleton, MA 01460		Phone:	(508) 486-1429