Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!ucsd!usc!cs.utexas.edu!rice!uw-beaver!ubc-cs!alberta!calgary!ctycal!ingoldsb From: ingoldsb@ctycal.UUCP (Terry Ingoldsby) Newsgroups: comp.arch Subject: Re: RISC vs CISC (rational discussion, not religious wars) Summary: True, but . . . Keywords: predictions Message-ID: <507@ctycal.UUCP> Date: 16 Nov 89 19:48:59 GMT References: <503@ctycal.UUCP> <15126@haddock.ima.isc.com> Organization: The City of Calgary, Ab Lines: 52 In article <15126@haddock.ima.isc.com>, news@haddock.ima.isc.com (overhead) writes: > In article <503@ctycal.UUCP> ingoldsb@ctycal.UUCP (Terry Ingoldsby) writes: > >It also seems to me that the current practice of throwing away computers > >every 3 years or so cannot continue forever; it is evidence of an > >immature technology that experiences quantum performance leaps every 3 > >years (that's what makes it fun :^). Eventually, performance improvements > >may taper off a bit, so the advantage of being able to design a chip in > >6 months instead of 18 will not be as great as it currently is. > > I used to think these things. I even worked for a company that > had a 25 year old CDC 6600 in production. The problem is this: > the maintenance on the old machines is higher than the cost of > new machines. It is still true, only less so. Why keep the > current machine on contract when you could just let the machine > break in six months (with some risk), and use the contract money > to buy a newer (and maybe) faster machine? > I *know* that it is cheaper to throw away old technology and bring in the latest and greatest. I have a three year old VAX that I would *love* to get rid of, if I could find anyone foolish enough to buy it. And you're right, the maintenance costs are a major portion of the justification. So is increased productivity and functionality on the part of the users. > We keep hearing how one physical limit or another will soon be > reached. I make this prediction: computers will continue getting > faster by the same expontial growth for the next ten years. Some > of the speed will come from raw hardware. Much of it will come > from more parallelism. RAM density will continue to increase. > Disk speeds and densities will get better. Backup media will get My point exactly, exponential growth for another 10 years. Maybe 15. At some point, *all* curves flatten. Besides the economic reasons for getting rid of old technology, there are economic penalties for constantly throwing away working systems. Aside from the obvious hardware waste (I've heard of working mainframes dismantled with hammers and thrown in garbage trucks) there are very substantial software porting costs. My point is that there will come a time when economics will dictate that machines not be thrown out every 3 years. Whether this will be in 5, 10 or 20 years I'm not sure. The technology curve will then remain flat until a quantum break- through takes place (analagous to the vacuum tube -> semiconductor revolution). I'm placing my bets on optical gates. When that breakthrough takes place, the whole thing will take off again and the added power will allow previously undreamable applications to be written. -- Terry Ingoldsby ctycal!ingoldsb@calgary.UUCP Land Information Systems or The City of Calgary ...{alberta,ubc-cs,utai}!calgary!ctycal!ingoldsb