From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-0.5 required=5.0 tests=BAYES_05,FREEMAIL_FROM autolearn=ham autolearn_force=no version=3.4.4 X-Google-Thread: 103376,8623fab5750cd6aa X-Google-Attributes: gid103376,public X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news1.google.com!news1.google.com!news.glorb.com!news3.optonline.net!newshosting.com!nx02.iad01.newshosting.com!216.196.98.140.MISMATCH!border1.nntp.dca.giganews.com!nntp.giganews.com!local1.nntp.dca.giganews.com!nntp.comcast.com!news.comcast.com.POSTED!not-for-mail NNTP-Posting-Date: Sun, 04 Jul 2004 14:00:13 -0500 Date: Sun, 04 Jul 2004 15:00:12 -0400 From: "Robert I. Eachus" User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.4) Gecko/20030624 Netscape/7.1 (ax) X-Accept-Language: en-us, en MIME-Version: 1.0 Newsgroups: comp.lang.ada Subject: Re: Improving Ada's image - Was: 7E7 Flight Controls Electronics References: In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Message-ID: NNTP-Posting-Host: 24.147.90.114 X-Trace: sv3-nhWQzj65Z2MY1LhFq59OuqW/poUCO75Xw2fvMGAgoLxsOsQK5ZRHD7Sp1QloA21/L8k7DK16WZyq555!xSfIq3ujh4mreJft9DPVpNeiaeJPrHVvWygSi2bnqTYWBOexNvFnzCAVTrp5dw== X-Complaints-To: abuse@comcast.net X-DMCA-Complaints-To: dmca@comcast.net X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.1 Xref: g2news1.google.com comp.lang.ada:2063 Date: 2004-07-04T15:00:12-04:00 List-Id: Dave Thompson wrote: > It was also designed to be reliable, even in the face of component > failures, although I didn't really experience that because we were in > effect an experimental site who *deliberately* shut down fairly often. I had accounts on bco-multics (Billerica, MA), as well as mit-multics, Phoenix AZ (System M), and hi-multics in Minneapolis. I remember a couple of shutdowns due to fried squirrels. (Jumping from the high voltage wiring into the building to the roof which had metal flashing could be very detrimental to a squirrel's health, and cause bco-multics to shut down when the breaker tripped.) Other than about two fried squirrels and a couple of scheduled updates in the OS, I can't remember any hardware or software related loss of service in five years. I am certain that during that time several dozen hardware failures of CPUs, disks, memory, tape drives and so on occurred. But in that sense Multics was totally fault tolerant. Once when I was in the computer room for some reason... (Now I remember, an upgrade to the network protocol.) I watched someone power down the CPUs replace the networking card, power that CPU up and go on to the next one. I worked at Stratus following Honeywell. A lot of the original Stratus personnel were ex-Multicians, including Bob Freiburghouse, one of the founders. I'd have to give Stratus, by the time I left, the edge on better fault tolerant support, but that was because Stratus systems allowed you do to a major OS upgrade, and transfer processes from the old OS version to the new without shutting them down. -- Robert I. Eachus "The flames kindled on the Fourth of July, 1776, have spread over too much of the globe to be extinguished by the feeble engines of despotism; on the contrary, they will consume these engines and all who work them." -- Thomas Jefferson, 1821