From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: tuhs-bounces@minnie.tuhs.org X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.1 Received: from minnie.tuhs.org (minnie.tuhs.org [45.79.103.53]) by inbox.vuxu.org (OpenSMTPD) with ESMTP id 4965d148 for ; Sat, 23 Jun 2018 06:08:42 +0000 (UTC) Received: by minnie.tuhs.org (Postfix, from userid 112) id 9A6DAA1857; Sat, 23 Jun 2018 16:08:41 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id ADDBB9EE0C; Sat, 23 Jun 2018 16:08:30 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id A5F2C9EE0C; Sat, 23 Jun 2018 16:08:28 +1000 (AEST) Received: from viclamta17p.bpe.bigpond.com (viclamta17p.bpe.bigpond.com [203.38.21.81]) by minnie.tuhs.org (Postfix) with ESMTPS id 3CE049EDE9 for ; Sat, 23 Jun 2018 16:08:27 +1000 (AEST) Received: from smtp.telstra.com ([10.10.26.4]) by viclafep17p-svc.bpe.nexus.telstra.com.au with ESMTP id <20180623060824.KFQM27281.viclafep17p-svc.bpe.nexus.telstra.com.au@smtp.telstra.com> for ; Sat, 23 Jun 2018 16:08:24 +1000 X-RG-Spam: Unknown X-RazorGate-Vade-Verdict: clean 0 X-RazorGate-Vade-Classification: clean X-RazorGate-Vade: gggruggvucftvghtrhhoucdtuddrgedtiedrtdejgddutddvucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuuffpveftpgfvgffnuffvtfetnecuuegrihhlohhuthemuceftddtnecunecujfgurhepfffhvffujgfkfhgfgggtsehmtddtredtreejnecuhfhrohhmpeffrghvvgcujfhorhhsfhgrlhhluceouggrvhgvsehhohhrshhfrghllhdrohhrgheqnecukfhppeduuddtrddugedurdduleefrddvfeefnecurfgrrhgrmhephhgvlhhopegrnhgvuhhrihhnrdhhohhrshhfrghllhdrohhrghdpihhnvghtpeduuddtrddugedurdduleefrddvfeefpdhmrghilhhfrhhomhepoegurghvvgeshhhorhhsfhgrlhhlrdhorhhgqecuuefqffgjpeekuefkvffokffogfdprhgtphhtthhopeeothhuhhhssehtuhhhshdrohhrgheqnecuvehluhhsthgvrhfuihiivgeptd X-RG-VS-CLASS: clean Received: from aneurin.horsfall.org (110.141.193.233) by smtp.telstra.com (9.0.019.26-1) id 5B0418AC04140CB2 for tuhs@tuhs.org; Sat, 23 Jun 2018 16:08:24 +1000 Received: from aneurin.horsfall.org (localhost [127.0.0.1]) by aneurin.horsfall.org (8.15.2/8.15.2) with ESMTP id w5N68Ntm015703 for ; Sat, 23 Jun 2018 16:08:23 +1000 (EST) (envelope-from dave@horsfall.org) Received: from localhost (dave@localhost) by aneurin.horsfall.org (8.15.2/8.15.2/Submit) with ESMTP id w5N68NH0015700 for ; Sat, 23 Jun 2018 16:08:23 +1000 (EST) (envelope-from dave@horsfall.org) X-Authentication-Warning: aneurin.horsfall.org: dave owned process doing -bs Date: Sat, 23 Jun 2018 16:08:23 +1000 (EST) From: Dave Horsfall To: The Eunuchs Hysterical Society In-Reply-To: Message-ID: References: <20180619204536.GA91748@server.rulingia.com> <20180620050454.GC91748@server.rulingia.com> <20180620081032.GF28267@eureka.lemis.com> <20180621030505.GA89671@server.rulingia.com> User-Agent: Alpine 2.21.999 (BSF 260 2018-02-26) X-GPG-Public-Key: http://www.horsfall.org/gpgkey.pub X-GPG-Fingerprint: 05B4 FFBC 0218 B438 66E0 587B EF46 7357 EF5E F58B X-Home-Page: http://www.horsfall.org/ X-Witty-Saying: "chmod 666 the_mode_of_the_beast" MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="1483753691-392379990-1529734103=:68981" Subject: Re: [TUHS] Old mainframe I/O speed (was: core) X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --1483753691-392379990-1529734103=:68981 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8BIT On Thu, 21 Jun 2018, Arrigo Triulzi wrote: >> for the microcode to customers. There were several hacks in there to >> slow down the disk I/O so that it didn't outperform the model 30. > > Is this the origin of the lore on “the IBM slowdown device”? If I remember my computer lore correctly, wasn't the difference between the Cyber 72 and the 73 just a timing capacitor, if you knew which board? And I still reckon that the olde 360/20 (I did see the console for one) should never have been part of the 360 series; * It had a HALT instruction! * It had about half the instruction set. * Half the number of registers, and width. * Floating point? What's that? Etc. A triumph of marketing over engineering... -- Dave, who did his CompSci thesis on the 360... --1483753691-392379990-1529734103=:68981--