From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 2265 invoked from network); 29 Nov 2021 01:18:25 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 29 Nov 2021 01:18:25 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id 4A8CA9CF44; Mon, 29 Nov 2021 11:18:21 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 45E5594613; Mon, 29 Nov 2021 11:16:40 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id AD89F94613; Mon, 29 Nov 2021 11:12:45 +1000 (AEST) Received: from mcvoy.com (mcvoy.com [192.169.23.250]) by minnie.tuhs.org (Postfix) with ESMTPS id 38A9A94586 for ; Mon, 29 Nov 2021 11:12:45 +1000 (AEST) Received: by mcvoy.com (Postfix, from userid 3546) id D169F35E5E1; Sun, 28 Nov 2021 17:12:44 -0800 (PST) Date: Sun, 28 Nov 2021 17:12:44 -0800 From: Larry McVoy To: Clem Cole Message-ID: <20211129011244.GJ18441@mcvoy.com> References: <202111282026.1ASKQ5X41437843@darkstar.fourwinds.com> <202111282115.1ASLFK1Q1438854@darkstar.fourwinds.com> <202111282147.1ASLlND41439656@darkstar.fourwinds.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) Subject: Re: [TUHS] A New History of Modern Computing - my thoughts X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: TUHS main list , Eugene Miya Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" On Sun, Nov 28, 2021 at 07:19:08PM -0500, Clem Cole wrote: > To me, the PDP-111 ISA is the epitome the *minimal computer architecture* > - just want you to need to get the job done be it commercial or scientific > and it was affordable as you said. The solution is elegant, nothing fancy, > little extra added - just the right set of features for a system to do real > work. It was also extremely regular as Larry points out, so it was not > filled with a ton of special cases. I remember Ken Witte (my TA for the PDP-11 class) trying to get me to see how easy it was to read the octal. If I remember correctly (and I probably don't, this was ~40 years ago), the instructions were divided into fields, so instruction, operand, operand and it was all regular, so you could see that this was some form of an add or whatever, it got the values from these registers and put it in that register. I remember Ken trying to get me to see how uniform it all was and I guess I sort of got it but what I remember the most is his passion for it. We were pretty friendly and if I had some big octal listing that wasn't working, he'd come over and drink a beer and read through it. For him, it was just faster to read the octal than to look at my tortured assembly. > 64 bit PDP-11 That would be pretty cool. Your comments about minimalist approaches ring really true for me. The last conversation I had with Greg Chesson was a 2 hour rant from him about the fact that nobody who is doing anything these days understands the value of a minimalist approach, it's one complex framework or whatever after another. There is a reason that the people I respect the most tend to spend a lot of time on what not to put in, rather than what to put in. I became friends with Linus Torvalds because we spent probably almost a year talking about what not to put in to LMbench, we wanted to get it right. I know people look at Linux and recoil in horror, it's a long way from v6 or v7. But v7 was a uniprocessor Unix that had no networking. Linux scales pretty well on SMPs with lots of CPUs, it has generalized NUMA support, it has a /proc that I'd argue is way more true to Unix than the SysV /proc (I don't know Ron Gomes but I was friends with Rodger Faulkner), the Linux /proc is all strings, it's so useful. Linux just handles way way way way way more than v7 could even imagine handling. Pretty much all of the supercomputers are Linux so it scales up and it scales down to a rasberry pi. A thing that blew my mind in Linux was drivers. PCI drivers. They were portable to different byte order machines. I was so used to drivers being specific to the CPU, that was eye opening. I'd say more but the wife is calling, I just wanted you to know that Linus definitely understands the minimalist approach, Linux started that way but it has been asked to do a lot so you get what you get. --lm