Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!columbia!rutgers!clyde!cbatt!ihnp4!inuxc!iuvax!bobmon From: bobmon@iuvax.UUCP (Robert Montante) Newsgroups: comp.sys.ibm.pc Subject: Re: Mainframes vs micros Message-ID: <2345@iuvax.UUCP> Date: Sun, 4-Jan-87 13:32:18 EST Article-I.D.: iuvax.2345 Posted: Sun Jan 4 13:32:18 1987 Date-Received: Mon, 5-Jan-87 02:36:10 EST References: <653@imsvax.UUCP> <196@unisoft.UUCP> <2841@gitpyr.gatech.EDU> Reply-To: bobmon@iuvax.UUCP (Robert Montante) Organization: Indiana University, Bloomington Lines: 39 > robert@gitpyr.UUCP (Robert Viduya): >>curt@charming.UUCP (Curt Mayer): >> Give me a break. I have never seen a CDC cyber with more than 05% load. >> This is in a university environment with 700+ users, no less. > >Is this 700+ simultaneous online users or just 700+ users in the validation >file? Our main computing engines, two CDC Cyber 855s and one CDC Cyber 990, >can only handle between a 100 and 200 users on simultaneously (per machine), >although the validation file has thousands of users in it. A couple of years ago I worked on an IBM 3090 (probably been upgraded again by now) that regularly had 400+ users on it. By regularly I mean that I got in at 7:30am to get to work because around 8:15am, when the Data Processing and Stat. Support people had gotten their coffee, the load would hit the 400+ number -- five days a week. I think the installation had three 3090's, only two of which were dedicated to interactive processing. Incidentally, I would guess that 60% of the terminals on that system were PC's. In my experience, the 400-user limit was defined by the system response time. At that number, response was poor enough that additional people would find something else to do. Another point: I would download whatever I could to the PC, thereby improving response time for me quite a bit. There was still quite a bit of work that couldn't be downloaded, either because the software was mainframe-resident only, or the data were mainframe-resident, or I was doing something that explicitly involved the networking features of the system. In short, my experience was that, in large environments, an explosive growth in the use of personal computers makes life marginally more bearable on the mainframes. There is still demand for all the mainframe capacity available, but more people struggle with the poor response times (instead of giving up entirely) because many of the smaller jobs move to the local machines. *-=-*-=-*-=-*-=-*-=-*-=-*-=-*-=-*-=-*-=-*-=-*-=-*-=-*-=-*-=-*-=-*-=-*-=-*-=-* Datclaimer: "[Usual disclaimer: I have no opinion, therefore I don't exist .]" Disclaimer: I opine, therefore I am. My employer, however, is a figment. RAMontante Computer Science "Have you hugged ME today?" Indiana University