Path: utzoo!attcan!ncrcan!becker!censor!comspec!tvcent!lethe!torsqnt!news-server.csri.toronto.edu!clyde.concordia.ca!uunet!cs.utexas.edu!rice!titan.rice.edu!preston
From: preston@titan.rice.edu (Preston Briggs)
Newsgroups: comp.arch
Subject: Re: i860 benchmarks?
Message-ID: <7435@brazos.Rice.edu>
Date: 7 May 90 05:25:38 GMT
References: <3632@newton.physics.purdue.edu> <24706@eerie.acsu.Buffalo.EDU>
Sender: root@rice.edu
Organization: Rice University, Houston
Lines: 25

In article <24706@eerie.acsu.Buffalo.EDU> pjg@acsu.Buffalo.EDU (Paul Graham) writes:
>cca@newton.physics.purdue.edu (Charles C. Allen) writes:
>|  They claim 80Mflops
>|for a single processor at 40Mhz.  What kind of MFlops are those?
>
>as i understand it they simply replay the numbers they got from intel.
>i believe these have some basis in linpack.

The 80 MFlop at 40 MHz number is the peak performance.
That is, it's the number you will never surpass.
Actual performance will be a lot lower, depending on your
application and compiler.

The best I've achieved is 48+ MFlops at 33 MHz,
for a 400x400 sigle precision matrix multiply.
This scales to about 64 MFlops if your memory will
keep up.  Note also that this was seriously restructured
code with the inner loop rewritten in assembly.
Note also that it's a factor of 21 faster than 
you'll get with a straightforward optimizing compiler.


--
Preston Briggs				looking for the great leap forward
preston@titan.rice.edu