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From: ktl@wag240.caltech.edu (Kian-Tat Lim)
Newsgroups: comp.arch
Subject: Re: Killer Micros and vectorized code
Message-ID: <14357@cit-vax.Caltech.Edu>
Date: 20 Mar 90 17:58:06 GMT
References: <51771@lll-winken.LLNL.GOV> <100598@convex.convex.com> <52661@lll-winken.LLNL.GOV> <100701@convex.convex.com>
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Reply-To: ktl@wag240.caltech.edu (Kian-Tat Lim)
Organization: California Institute of Technology, Pasadena, CA
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In-reply-to: hamrick@convex1.convex.com (Ed Hamrick)

In article <100701@convex.convex.com>, hamrick@convex1 (Ed Hamrick) writes
[in reference to the Alliant FX/2800]:
>If you have a chance, ask the Alliant people what their Linpack 100x100
>performance is, and see how well it scales up to 28 processors.  Try to
>get real runs, not estimates.  I'd also be curious about main memory
>bandwidth (not crossbar bandwidth).  Information like number of banks,
>number of bytes read per bank access, and bank cycle time would be
>particularly interesting.

From publicly-available Alliant literature:

	MEMORY SYSTEM
	Cache size 512KB per module, 4MB max
	Processor to Cache Bandwidth: 1.28GB/sec [through the crossbar]
	Maximum Physical Memory: 1GB
	Interleaving: 16-way on a single board
	Memory Bus Bandwidth: 640MB/sec

I believe that Alliant has run 100x100 Linpack on a 28 processor
system, but I'm not sure if that figure has been made public.  It's
probably obvious that it won't be 28 times the raw i860 number (11
MFLOPS).
-- 
Kian-Tat Lim (ktl@wagvax.caltech.edu, KTL @ CITCHEM.BITNET, GEnie: K.LIM1)
Perl is the Swiss Army chainsaw [of Unix programming]. -- Dave Platt's friend