Path: ...!news.iecc.com!.POSTED.news.iecc.com!not-for-mail From: John Levine Newsgroups: comp.arch Subject: Re: The Design of Design Date: Thu, 25 Apr 2024 22:13:33 -0000 (UTC) Organization: Taughannock Networks Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Injection-Date: Thu, 25 Apr 2024 22:13:33 -0000 (UTC) Injection-Info: gal.iecc.com; posting-host="news.iecc.com:2001:470:1f07:1126:0:676f:7373:6970"; logging-data="58558"; mail-complaints-to="abuse@iecc.com" In-Reply-To: Cleverness: some X-Newsreader: trn 4.0-test77 (Sep 1, 2010) Originator: johnl@iecc.com (John Levine) Bytes: 2557 Lines: 32 According to Stephen Fuld : >Thomas Koenig wrote: > >> John Levine schrieb: >> >> > They had the insight to see that the 16 fixed sizs registers could >> > be in fast storage on high end machines, main memory on low end >> > machines, so the high end machines were fast and the low end no >> > slower than a memory-memory architecture which is what it in >> > practice was. It was really an amazing design, no wonder it's the >> > only architecture of its era that still has hardware >> > implementations. > >Yes, although it isn't clear how much of its success is due to >technical superiority versus marketing superiority. S/360 invented eight bit byte addressed memory with larger power of 2 data sizes, which I think all by itself is enough to explain why it survived. All the others, which were word or maybe decimal digit addressed, died. Its addresses could handle 16MB which without too many contortions was expanded to 2GB, a lot more than any other design of the era. We all know that the thing that kills architectures is running out of address space. I thought the PDP-10 was swell, but even if DEC had been able to design and ship the Jupiter follow-on to the KL-10, its expanded addressing was a kludge. It only provided addressing 8M words or about 32M bytes with no way to go past that. -- Regards, John Levine, johnl@taugh.com, Primary Perpetrator of "The Internet for Dummies", Please consider the environment before reading this e-mail. https://jl.ly