Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!rochester!ritcv!cci632!rb From: rb@cci632.UUCP (Rex Ballard) Newsgroups: comp.sys.misc Subject: Re: Why a Micro is not as powerful as a Vax Message-ID: <805@cci632.UUCP> Date: Tue, 6-Jan-87 12:48:52 EST Article-I.D.: cci632.805 Posted: Tue Jan 6 12:48:52 1987 Date-Received: Tue, 6-Jan-87 22:43:03 EST References: <984@hounx.UUCP> <2880@rsch.WISC.EDU> <1611@hoptoad.uucp> <1920@alvin.mcnc.UUCP> Reply-To: rb@ccird2.UUCP (Rex B) Distribution: world Organization: CCI, Communications Systems Division, Rochester, NY Lines: 56 Keywords: micro vax 750 Summary: Why it is and is not. This debate is hardly new. One of the key points in determining which is "better" for a specific set of needs is to determine what is actually needed. First, a mini or mainframe has access to, and needs, more storage. If you wanted to access 4 gigabytes of data, application code, and tools, a mini or mainframe is probably a good idea. Even with CPU speed being divided among 100 or more users, it is likely, especially with "text only" processing, that the CPU won't be that heavily loaded, but rather that the drives will be "crunching away". On the other hand, if you want to do bit-mapped manipulations of graphics, windows, what-you-see-is-what-you-get editing, and similar loads that require a great deal of CPU overhead dedicated to one user, it's probably a good idea to incorporate a micro into the user level interface. In spite of the CPU benchmarks, the figures are very misleading. A VAX for example runs the main CPU at about the same speed as the Atari ST, yet when connected to 100 or so VT-100's or Techtronix terminals, and additional effective 10 to 100 mips is being used in a "distributed functionality" mode. In many cases the "VT-100" isn't a terminal at all, but rather a "terminal emulator", often running at speeds of up to 1 MIPs. Mainframe people like to think of micros/terminals/emulators/... as "dumb tubes" and attempt to do as much of the "intelligent work" in the host. Micro people tend to think of servers, telecommunications services, videotex,... as "dumb disks" and attempt to to the "intelligent work" in the micro. Slowly, the interconnections between host and micro are becoming more sophisticated. Interfaces like X-windows, and various "remote file systems" are causing a closer blend and a tighter, more efficient interface between the two. As this occurs, both "micro" and "mainframe" become more productive, with the mainframe handling more users and more storage, and the micros handling more complex presentation. Perhaps in a few years, we'll start seeing integration of Host and Micro become so tight that systems such as a VAX 8600 cluster, or a 6/32-FT will be running as many as 1000 users, 10 or 20 intelligent disk drives (built in caching, i-node searching, directory traversal...) and developing performance numbers measured in BIPS (billion instructions/second). A good example of such integration would be a simple editor. The host would appear to be running effectively a "line editor" like ed, the "disk drive" would be inserting and deleting blocks from the file, and the micro would be handling font presentation and converting the visual information to "ed" and/or NROFF type commands to the host. With proper load balancing, it would be possible to reach speeds well into the 2 BIPS region. Anybody wanna buy a used crystal ball? Rex B.