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,MIME_QP_LONG_LINE,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 214c35ff for ; Fri, 22 Jun 2018 05:42:21 +0000 (UTC) Received: by minnie.tuhs.org (Postfix, from userid 112) id 23293A181E; Fri, 22 Jun 2018 15:42:20 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 066A3A1817; Fri, 22 Jun 2018 15:41:42 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id D3FB4A1817; Fri, 22 Jun 2018 15:41:39 +1000 (AEST) X-Greylist: delayed 538 seconds by postgrey-1.35 at minnie.tuhs.org; Fri, 22 Jun 2018 15:41:39 AEST Received: from cesium.clock.org (cesium.clock.org [157.22.10.65]) by minnie.tuhs.org (Postfix) with ESMTPS id 2E32AA1816 for ; Fri, 22 Jun 2018 15:41:39 +1000 (AEST) Received: from cesium.clock.org (localhost [127.0.0.1]) by cesium.clock.org (Postfix) with ESMTP id 18132CC3AB; Thu, 21 Jun 2018 22:32:39 -0700 (PDT) From: "Erik E. Fair" In-reply-to: References: To: Paul Winalski Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 Date: Thu, 21 Jun 2018 22:32:39 -0700 Message-ID: <27914.1529645559@cesium.clock.org> 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: , Cc: The Eunuchs Hysterical Society Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" The VAX 8800 was also the advent of the DEC BI bus attempt to lock third-party = I/O devices out of the VAX market and prevent "unauthorized" competition with = their own overpriced and underperforming I/O devices. In late 1988 or early 1989 my group at Apple ordered a VAX-8810 to replace two = 11/780s on the promise from DEC that all our UniBus and MASSbus peripherals = would still work ... which we knew (from others on the Internet who'd tried = and reported their experiences) to be a lie. After allowing DEC field circus to embarass themselves for a while trying to = make it work, we cancelled our 8810 order and bought two 8650s instead (they = cost half as much!), which we knew would run 4.3 BSD UNIX (unlike the 8800 = series where we'd be stuck with Ultrix) and where all our old but still useful = peripherals would still work. Surprise, DEC - your customers talk to each = other and compare notes. IIRC, as a consolation for DEC, we still bought a heavily discounted 6000 = series BI machine with all new I/O to handle some other tasks that the 8650s = weren't doing while also making clear to DEC that we understood the game they'd = tried to play with us. After that, Apple engineering concentrated on Sun & SGI gear, along with our = Cray running UniCOS, but Apple IS&T (corporate IT) bought quite a bit of VAX = gear to run VMS for certain applications they had to support. Part of being in the Unix community was participating it as a community and = sharing experiences like this for the benefit of all (and to keep hardware = vendors honest) - the Unix-Wizards Internet mailing list, and comp.unix USENET = newsgroup were invaluable in this regard. Erik Fair >Date: Thu, 21 Jun 2018 16:39:23 -0400 >From: Paul Winalski > >On 6/21/18, Arrigo Triulzi wrote: >> On 21 Jun 2018, at 16:00, Paul Winalski 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 =E2=80=9Cthe IBM slowdown device=E2=80= >=9D? >> >> I seem to recall there was also some trickery at the CPU level so that yo= >u >> could =E2=80=9Cfield upgrade=E2=80=9D between two models by removing it b= >ut a) I cannot find >> the source and b) my Pugh book is far and cannot scan through it. > >I don't know about that for IBM systems, but DEC pulled that trick >with the VAX 8500 series. Venus, the successor to the 11/780, was >originally to be called the 11/790 and was done in ECL by the PDP-10 >folks. The project suffered many delays and badly missed its initial >market window. It eventually was released as the VAX 8600. It had a >rather short market life because by that time the next generation CPU, >codenamed Nautilus and implemented in TTL, was nearly ready for market >and offered comparable performance. There was also a slower and lower >cost system in that series codenamed Skipjack. When it finally came >time to market these machines, it was found that the product line >needed a reduced cost version of Skipjack. Rather than design a new >CPU, they just put NOPs in the Skipjack microcode to slow it down. >The official code name for this machine was Flounder, but within DEC >engineering we called it "Wimpjack". Customers could buy a field >upgrade for Flounder microcode that restored it to Skipjack >performance levels. > >-Paul W.