Newsgroups: comp.arch
Path: utzoo!utgpu!cunews!alfred!greg
From: greg@organia.sce.carleton.ca (Greg Franks)
Subject: Re: Can old architectures run fast?
In-Reply-To: dmocsny@minerva.che.uc.edu's message of 6 May 91 22:04:29 GMT
Message-ID: <GREG.91May7102722@organia.sce.carleton.ca>
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References: <8283@uceng.UC.EDU> <7628@auspex.auspex.com> <8324@uceng.UC.EDU>
	<1991May05.174756.9026@iecc.cambridge.ma.us> <8346@uceng.UC.EDU>
Date: 7 May 91 10:27:22

In article <8346@uceng.UC.EDU> dmocsny@minerva.che.uc.edu (Daniel Mocsny) writes:

   In article <1991May05.174756.9026@iecc.cambridge.ma.us> johnl@iecc.cambridge.ma.us (John R. Levine) writes:
   >In article <8324@uceng.UC.EDU> dmocsny@minerva.che.uc.edu (Daniel Mocsny) writes:
   >>Are we likely to see the fastest CPU in year X being able to run,
   >>without change, a binary program more than 5 years old? ...
   >Well, there's always the IBM 360.  You can still run 1965 vintage 360
   >binaries on IBM's latest 3090 mainframe.

   That is truly impressive, in fact, it's rather astounding. But I see 
   I left cost out of my question. So let me try another wrinkle:

   How does a 3090 stack up against modern workstations on the usual
   measures of performance/price, such as SPECmarks/$? My guess would
   be that the large backwards compatibility comes at a price.

   Also, how much slower and/or more expensive is the 3090 as a result
   of maintaining such backwards compatibility? (I realize that might be
   hard to get a handle on.)

However, people who purchase IBM 3090's are not interested in
SPECmarks/$$ because they are more interested in MBytes/second of
transfer from the disk farm to the CPU and back.  Most workstations of
the SPECmarks/$$ fall flat on their face when it comes to I/O systems.

(They also want to run five levels of emulation so that their anchient
accounting program doesn't have to be changed :-)
--
Greg Franks, (613) 788-5726               | "The reason that God was able to    
Systems Engineering, Carleton University, | create the world in seven days is   
Ottawa, Ontario, Canada  K1S 5B6.         | that he didn't have to worry about 
greg@sce.carleton.ca  ...!cunews!sce!greg | the installed base" -- Enzo Torresi  
