I reposted to a.f.c. and linkedin groups ... some comments one might claim that amdahl's clone was more "IBM 360" than the 3081
Amdahl wanting to do ACS-360 http://people.cs.clemson.edu/~mark/acs_end.html but canceled because it would have advanced computing too fast, endangering IBM's control of the market. Amdahl leaves and IBM launches into FS ... which was going to be completely replace 360 and be completely different. Amdahl does a 360, but at his own company ... the lack of IBM 360 products during the FS period is credited with giving the "clones" market foothold. http://www.cs.clemson.edu/~mark/fs.html http://en.wikipedia.org/wiki/IBM_Future_Systems_project http://gdrean.perso.sfr.fr/papers/promises.html past posts http://www.garlic.com/~lynn/submain.html#futuresys After billions of (early 70) dollars, Future System implodes w/o being announced ... and then there is mad rush to get products back into the 360/370 product pipelines. http://www.jfsowa.com/computer/memo125.htm 3033 starts out being 168 remapped to some left-over FS 20% faster chip technology ... followed by 3081 that is still more left-over FS technology ... from above: The 370 emulator minus the FS microcode was eventually sold in 1980 as as the IBM 3081. The ratio of the amount of circuitry in the 3081 to its performance was significantly worse than other IBM systems of the time; its price/performance ratio wasn't quite so bad because IBM had to cut the price to be competitive. The major competition at the time was from Amdahl Systems -- a company founded by Gene Amdahl, who left IBM shortly before the FS project began, when his plans for the Advanced Computer System (ACS) were killed. The Amdahl machine was indeed superior to the 3081 in price/performance and spectaculary superior in terms of performance compared to the amount of circuitry.] ... snip ... 168 was enhancement to 165 with faster memory technology and better optimization of the 165 horizontal microcode getting avg. machine cycle per 370 instructions down to 1.6 from 2.1. In that sense, the next new (high-end 370) processor after the 165 in 1970 (except for 168 & 3033 increments and 3081 FS left-over) was 3090 in 1986, more than 15 years later. At the end of the ACS-360 article there is section on features from ACS-360 finally showing up in IBM ES/9000 announced in 1990. -- virtualization experience starting Jan1968, online at home since Mar1970 ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
