Volume 4, Number 27 20 July 1987 +---------------------------------------------------------------+ | _ | | / \ | | /|oo \ | | - FidoNews - (_| /_) | | _`@/_ \ _ | | International | | \ \\ | | FidoNet Association | (*) | \ )) | | Newsletter ______ |__U__| / \// | | / FIDO \ _//|| _\ / | | (________) (_/(_|(____/ | | (jm) | +---------------------------------------------------------------+ Editor in Chief: Thom Henderson Chief Procrastinator Emeritus: Tom Jennings FidoNews is published weekly by the International FidoNet Association as its official newsletter. You are encouraged to submit articles for publication in FidoNews. Article submission standards are contained in the file ARTSPEC.DOC, available from node 1:1/1. Copyright 1987 by the International FidoNet Association. All rights reserved. Duplication and/or distribution permitted for noncommercial purposes only. For use in other circumstances, please contact IFNA. Four Weeks to FidoCon! Table of Contents 1. ARTICLES ................................................. 1 FidoNet Conference Information ........................... 1 Tentative Conference Agenda .............................. 2 Living with DOS: Disk Caches ............................ 4 MGM: A New Echomail System ............................... 15 Tandy User Group Newsletter .............................. 18 FUN messing with USERS or I'll be Dutched ................ 22 2. COLUMNS .................................................. 27 The Broadcasters Booth - 24 hr mail ...................... 27 The Regular Irregular Column ............................. 29 3. WANTED ................................................... 34 INFORMATION "FEEDS" WANTED ............................... 34 4. NOTICES .................................................. 35 Don Brauns ............................................... 35 The Interrupt Stack ...................................... 35 Latest Software Versions ................................. 36 International FidoNet Conference Registration Form ....... 37 IFNA Order Form and Membership Application ............... 38 FidoNews 4-27 Page 1 20 Jul 1987 ================================================================= ARTICLES ================================================================= Irene Henderson, 1:107/9 Fourth International FidoNet Conference August 20th to 23rd FidoNet Conference Information Your participation will help to ensure a successful and informative conference. Send in your registration form NOW. The registration form for the conference does not include hotel accommodations. The conference will be held at the Radisson Mark Plaza Hotel. If you wish to stay there you must contact the hotel directly. Radisson Mark Plaza Hotel 5000 Seminary Road., Alexandria, VA 22311 1-800-228-9822 Mention that you are with the FidoNet Conference and you will receive discounted room rates. The Radisson has agreed to extend these rates for any who wish to stay on after the conference and visit our nation's capital. The Radisson provides free transportation to and from National Airport any time of the day. A Metro stop (subway) at the airport will give you access to the Smithsonian, the Zoo, and other national landmarks in the District. Room Rates for the Conference: Single or Double Occupancy: $80.00 /night One additional cot in a room: $20.00/night Children under 17 accompanied by an adult: Free If you wish to share a room and need a roommate, please contact Brian Hughs at 109/634. He will help you find someone to share a room with. NOTE: You must register with the Radisson before August first to be guaranteed the discounted room rate! Book your room NOW! There are four restaurants in the Radisson ranging from relatively "inexpensive" to "very, very, expensive". The sysops in net 109 are compiling a list of establishments in the surrounding neighborhood which will be available when you get to the conference. During the Conference there will be a Banquet on Friday night and a luncheon on Saturday. If you are interested in attending these, don't forget to mark them on your registration form. ----------------------------------------------------------------- FidoNews 4-27 Page 2 20 Jul 1987 Fourth International FidoNet Conference August 20th to 23rd Alexandria, Virginia Tentative Conference Agenda I. Thursday Night A. 1500 Registration B. 1900 Welcome party - Cash bar - Free hors-douvers C. 2100 Deadline for IFNA Board of Directors votes II. Friday Morning A. 0900 Opening ceremonies - Ken Kaplan, Executive Director of IFNA - Thom Henderson, Editor of FidoNews - New Board of Directors introduced 1. Bob Morris, Chairman of Nominations and Elections B. 1000 Report from the FidoNet Standards Committee - Ryugen Fisher, Chairman of the FTSC - Ben Baker - Thom Henderson - Bob Hartman C. 1100 High speed modems - Bob Hartman, Chairman of the 9600 baud subcommittee - Ray Gwinn - Gee Wong III. Break for lunch IV. Friday Afternoon - Technical Track A. 1330 Fido Version 12 - Tom Jennings B. 1430 Opus - Vince Perriello C. 1530 TBBS - Phil Becker D. 1630 Dutchie - Henk Wevers V. Friday Afternoon - Legal Track A. 1330 Patents, Copyrights, and Trademarks - Tom Marshall, Esq. B. 1430 Amateur and Commercial Electronic Mail - Mike Cavanaugh Electronic Mail Association C. 1530 Legal Aspects of Electronic Mail - Philip M. Walker Vice President and Regulatory Council Telenet Communications Corporation D. 1630 Legal Issues Arising for BBS Sysops - Rees Morrison Sysop, Author, and member of the Bar - Jonathan Wallace Sysop of Compuserve Law SIG FidoNews 4-27 Page 3 20 Jul 1987 VI. Banquet A. 1930 Dinner B. 2030 Speaker - George Bond Senior Executive Editor Byte Information Exchange (BIX) VII. Saturday Morning A. 0900 FidoNet in North America - Ben Baker, Zone 1 Coordinator B. 1000 FidoNet in Europe - Henk Wevers, Zone 2 Coordinator C. 1100 FidoNet on the MacIntosh - Michael Connick Author of "The Mouse Exchange" III. Luncheon A. 1200 Lunch B. 1300 Speaker - To Be Announced Chairman of the Board of Directors IX. Saturday Afternoon A. 1330 Routing - Ben Baker B. 1430 Extended Addressing: Zones and Points - Thom Henderson - Henk Wevers C. 1530 Future Directions for EchoMail - Bob Hartman - Phil Becker - Gee Wong - Thom Henderson D. 1630 The FidoNet<=>UseNet Gateway - Speaker to be announced X. Sunday A. 1000 IFNA Board of Directors meeting - Open to all IFNA members Pre-registration required - Breakfast will be served ----------------------------------------------------------------- FidoNews 4-27 Page 4 20 Jul 1987 Living with DOS Disk Caches by Barry Simon Copyright (c) 1987, Capital PC User Group Inc. This material may be republished only for use by other not-for-profit user groups. I/O, I/O, Its Off to Work We Go! There is much noise made about running 286 based machines at 8, 10 or even 12 Megahertz. While running your computer's microprocessor at a faster speed will make a difference, for many tasks the difference is bounded because the limiting factor is often the speed of your input and output devices known collectively as I/O. That these devices slow down the CPU is seen by the typical times involved. 8 MHz means that the CPU goes through 8 million cycles per second. Since a single instruction on the 80xx family of chips takes from two to over twenty cycles, a CPU in the current generation of MS-DOS machine can run at roughly 1 MIPS (millions of instructions per second). Memory chips are rated at speeds of 70-200 nanoseconds. A nanosecond is a billionth of a second which means that such chips are capable of speed comparable to CPU speeds. That the speeds are slightly less is shown by the need for "wait states", which slow down the CPU to allow access to memory at its speed; RAM speeds, however, are roughly equal to those of the CPU. I/O speeds are considerably less. Even a fast hard disk rated at 20 milliseconds has a rated speed 100,000 times the speeds associated to RAM. Of course, because the RAM speed is a statement about each access and hard disk access times involve the first access of a disk sector, the actual ratios are not that bad. But memory access, even by slow memory chips, is much faster than even speedy hard disks; diskettes are even slower. While disk transfer rates are slower than RAM exchanges, they are speedy compared to output through parallel or serial ports, where transfer rates are measured in 100's of bytes per second. (1200 baud, for example, means roughly 120 characters per second.) And your console, the name for the combined keyboard/monitor I/O device must interface the computer's slowest component -- you; its speeds are often the slowest of all. There are software tools to try to speed up I/O especially by using RAM for certain operations. This month, I'll discuss one category of those tools -- disk caches; programs that can substantially speed up disk access. In this article, I discuss six commercial and one shareware disk cache programs; the programs are: o Emmcache, a shareware product by Frank Lozier; FidoNews 4-27 Page 5 20 Jul 1987 o Lightning from the Personal Computer Support Group; o Polyboost from Polytron; o Quickcache from Microsystems Developers, Inc.; o Speedcache from FSS Ltd; o Super PC-Kwik from Multisoft Corp.; and o Vcache from Golden Bow Systems. What Is a Disk Cache? Disk caches are based on the idea that you are likely to want to access a file that you accessed recently. This is not only true for obvious data files like a database which you might search several times in a row, but also for program overlays and for the files that DOS often consults to locate other files: the FAT and the various directories, especially the root directory. Thus every time that a file is accessed, a cache will keep a copy of that file in memory set aside especially for that purpose. Since this special memory is limited, the cache has to have an algorithm to decide which parts of the cache to clear out to make room for new sectors. All the caches under discussion use the algorithm of discarding those parts of the cache which were least recently accessed; that is, not the ones that were first read the longest ago but rather than ones which were needed longest ago. Whenever DOS calls for a sector from disk, the cache program intercepts the call to check if the requested material is in the cache memory. If it is, the copy in memory is used and a disk access is saved. A cache can avoid anywhere from one-third to two-thirds of your disk accesses. To allow a large cache, it is natural to put the data part of the cache (that is, the copies of the sectors which were read rather than code that controls this data) in extended or expanded memory. For safety's sake, you would not want these programs to delay writing to disk material that DOS wants to write to disk; this is called keeping dirty buffers and none of these programs keep dirty buffers. However, as I'll explain, DOS does some of its own disk caching and it does keep dirty buffers which can produce problems. Do not confuse keeping dirty buffers, that is delaying writing to disk, with caching writes. The latter means that the cache writes to disk but keeps a copy of the material which is written to disk if it is different from the copy that was read previously. For example, if you load a file in your word processor, change it and save it, a program that caches writes will save a copy of the final file version in its cache while one that does not, will not keep such a copy. All the commercial programs discussed in this article cache writes, but Emmcache FidoNews 4-27 Page 6 20 Jul 1987 does not. When I first started using a cache, I found the experience eerie. I'd do some action that I often did and wondered why my disk access light wasn't going on. Types of Memory In our discussion of caching, various references will be made to the different kinds of memory that are available to microcomputer users. These include: o Conventional memory, the 640K of Random Access Memory (RAM) that is readily accessible by most 8088/8086/80186 computers. o Extended memory, the memory above 1 megabyte (up to 16 megabytes) that is accessible by 80286 computers. This memory is not normally accessible for use as conventional memory but is generally used for RAM disks, disk caches