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From: djh@xipe.osc.edu (David Heisterberg)
Newsgroups: comp.benchmarks
Subject: Re: Don't use bc (was: More issues of benchmarking)
Message-ID: <1211@sunc.osc.edu>
Date: 5 Dec 90 23:05:43 GMT
References: <39871@ucbvax.BERKELEY.EDU> <1990Dec3.204027.16794@cs.utk.edu> <109872@convex.convex.com>
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In article <109872@convex.convex.com> patrick@convex.COM (Patrick F. McGehearty) writes:
>	program main
>	real*8 a(256,256),b(256,256),c(256,256)
>	call matmul(a,b,c,256)
>...
>	  do k = 1, n
>	    c(i,j) = c(i,j) + a(i,k)*b(k,j)
>	  enddo

Won't Convex performance suffer here due to bank conflicts?  At least on
a CRAY, the above algorithm would not (or should not) find a place in any
production code.  The inner loop would be run over "i".
--
David J. Heisterberg		djh@osc.edu		And you all know
The Ohio Supercomputer Center	djh@ohstpy.bitnet	security Is mortals'
Columbus, Ohio  43212		ohstpy::djh		chiefest enemy.