test-drb October 1999

test-drb@ccmp.vtda.org

216 participants
748 discussions

Benchmark Wars (was Re: gauging interest in VAX 6000-530)

by allisonp＠world.std.com

<> If you're doing ray tracing, get a fast PC. <> If you're timesharing dozens of people, a VAX is not a bad choice. < <I remain unconvinced(!). Then what would work better for fast ray tracing. and why does my ISP have a 24x250mhz SGI and not 24 PIII/xeons? <> It's all about "balance" and truly good designers can get good balance fo <> the task at hand without being stuck in some rut. Big time Chuck. I like the mix, I like to mix. Thinking of the 11/55 story. 1970, KA10 (PDP10) 300 users (mostly TTYs) in schools never using more than maybe 70%. Plus batch processes for version clerical tasks related to the operation of the BOCES LIRYCS timeshare system. Now That was BIG iron (12 6ft racks!). But if I took all the PCs needed to provide the same interconnected services and stacked them up they would easily outweigh the KA10 and much more power, try 300x200W that is 60KW, the Ka10 was under 10KW and like near 6KW. <> (For Mike, have you ever actually run a 486 based PC architecture machine <> with a dozen actual serial interfaces connected to terminals? It is <> instructive because the damn things saturate the ISA bus and no disk <> traffic happens at all! < <(Hi Chuck!) < <Here's my back-of-the-envelope: < <The 16-bit ISA bus on a 486dx2/66 runs at 8 MHz. The total bus throughput <for memory operations is 32 megabits/sec. (4 cycles = 500 ns, 16 bits/cycle yes, but the IO is polled or interrupt and that adds 500% overhead. <If your dozen uarts are on a memory-mapped card, and you're pumping 19.200 <b/s continuously to the dozen uarts, that's 184,320 b/s required by the <uarts. That's only about 0.6% of the available bus bandwidth (about one <uart transfer every 174 Main Memory references.) Yes, you do have to work <with such slow memory, and now we understand why cache memory was so import <even on dx2/66 motherboards. So, yeah, keeping a dozen terminals blazing <output would be "fun" with an ISA-only bus! It's not 184320, thats how many are transfered, not the process loading. The system might require that to be dispersed across 12 buffers and there are overheads associeted with that. So your understating the actual task and loading. While the ISA bus is running at its speed the cpu is basically locked to that and the memory accesses that could occur, don't. The actual performance is not impressive. FYI: vax using the same approach would really be poor too. This kind of IO was typical of PDP-11s and they did it very well. The big iron solution is hardware and non competeing busses to unload the cpu from the IO task and not burden the memory with the slow IO cycles. Therein is part of the difference. Old iron treated the cpu as a valuable resource and were designed with the idea that cpu cycles were expensive. <(Incidentally, I am -not- advocating ISA as some sort of "wunderbus"; on th Yes it's perfomance is par with mid range(ca 1977) unibus and Qbus of 10 years before. By 1981 DEC had decided that those busses were ok for their use but they needed faster buses. FYI BI bus was a 64bit bus (minimum access was a 8byte chunk) and in use about 8 years before PCI was conceived (or VESA, VL). the big iorn was always trying to feed the data rate habit and usually long before PCs. < contrary, I remain amazed that it has taken the PC industry as long as it < has to recognize the importance of I/O speed. 64-bit 66 MHz PCI and 2x AG < are steps in the right direction... Yes, the microcomputer industry seem < hellbent on re-discovering what the mainframe and mini guys knew 20 or 40 < years ago...) Yes. thats the whole point. Allison

25 years, 1 month

Last chance before they hit SCRAP...

by CLASSICCMP＠trailing-edge.com

>I've got a fair number of ST41201J SMD drives (1.2G) in System Industries >carriers in Milpitas (near San Jose); if anyone needs them we can work out >a trade. > >I've recently learned that there are different flavors of SMD. The >high-transfer rate drives use the SMD-E interface, which uses differential >ECL transceivers for the data and clock on the radial interface, vs. >TTL-compatible stuff on the earlier drives. I thought all SMD interface drives used differential ECL signals on the radial cables... >I'm hoping to use some of these on a system that was originally set up for >Fujitsu Eagles (M2351), but I haven't found any online reference that >indicates the data transfer rate or geometry of the Eagle, or whether >it uses SMD-E. A very good source of SMD drive geometry information is the "Sun format.dat" file that's been floating around the net for the past 15 years or so. The Eagle is 842 Cylinders, 20 Heads, and (assuming 512 bytes/sector) 49 or 50 sectors per track. The data rate is 15 MHz. Is this what you needed to know? I have manuals for most of the Fuji drives. Incidentally, the Fuji Eagle manual is titled "M2351A/AF Mini-Disk Drive Customer Engineering Manual". Most weenies today wouldn't call a drive that weighed over 100 pounds "Mini", but they don't know what they're talking about! -- Tim Shoppa Email: shoppa(a)trailing-edge.com Trailing Edge Technology WWW: http://www.trailing-edge.com/ 7328 Bradley Blvd Voice: 301-767-5917 Bethesda, MD, USA 20817 Fax: 301-767-5927

25 years, 1 month

OT: how big would it be?

by CLASSICCMP＠trailing-edge.com

>> Of course you could, but why would you want to? What's the problem with >> PCBs (or am I going to find out for myself when I get seriously into >> making them at home?) >Nothing except that I thought they were a more recent innovation. Than... ? > I was >thinking along the lines of, this is how you might build it with technology >available in 19XX Printed circuit boards were used in consumer electronics as early as the late 1940's. These were true "printed circuits" (i.e. copper traces applied to substrate) and not the wamsy-pamsy etched circuits you'll find today :-). -- Tim Shoppa Email: shoppa(a)trailing-edge.com Trailing Edge Technology WWW: http://www.trailing-edge.com/ 7328 Bradley Blvd Voice: 301-767-5917 Bethesda, MD, USA 20817 Fax: 301-767-5927

25 years, 1 month

Punch Cards

by BSands8417＠aol.com

I am setting up a class for 6-7 graders and need a few punch/hollerith, etc. cards to demonstrate past equipment/practices. Can anyone help? Thanks Ben Sands Bsands8417(a)aol.com

25 years, 1 month

Reliable PCBs at home

by edick＠idcomm.com

This appears to be the procedure, though I forgot to mention that the copper has to be applied electrically to the drilled boards prior to application of the second (after the .000030" flash of copper which is chemically applied, but the dry-film I meant was indeed the solder mask. All my boards were made with dry-film solder mask, since that worked so well for my wirewrap boards. I liked the appearance, and silkscreened legends went on top of it wit little smearing and blurring, so they could be REALLY small. I never considered letting a shop do parts of the job, but I'll explore that before I give up completely. thanks for the explanation. Dick -----Original Message----- From: Marvin <marvin(a)rain.org> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Sunday, October 24, 1999 10:48 PM Subject: Reliable PCBs at home > > >Richard Erlacher wrote: >> >> First of all, I haven't read ALL of this thread, but I recall Tony or >> someone else replying to him saying something about the method for making >> plated through two-sided boards in your home. I've never met anyone aside >> from professionals with scads of equipment who could do that, but it seems >> to me that the method which was described to me was to start with bare >> fiberglass/epoxy panels, drill them, then apply a slightly conductive >> coating in liquid form which had to be forcibly dried (perhaps baked) before >> the resist was applied. The boards were then exposed, the films applied to >> registration targets on each side, to a powerful UV light, for which some >> prefer to use direct sunlight, and the boards subsequently developed, then >> etched. >> >> Has any of you ever encountered an approach to this that could be managed in >> the home environment with equipment costing, nominally, less that a k-buck >> or two and achieving nominally 10-mil traces with 8-10 mil separation or >> anything close to that? How about a dry-film solder mask? > >First of all, there are service shops that will take a drilled board, do the >PTH process, and electroplate the desired amount of copper onto the board. >The normal process for making PTH boards is as follows. > >The copper clad laminate is cut to panel size and drilled. The drilling is >usually done on an NC machine. The NC program can either be supplied as a >drill file, or it can be hand programmed. Hand programming involves taping >the artwork (or more likely a copy) to a programing table, marking the rout >to follow for each drill size, and then just the grunt work of centering >each hole in a scope, and pushing a foot pedal that records that location. > >There are a number of different processes for doing PTH, but the most common >is to take the drilled panel(s), run it through an electroless copper line >(cleaning, catalist, accellerator, electroless copper) that will put about >30 millionths of copper on the board, and electroplate about .3 mill or so >of copper on the bare panel (enough so the rest of the process doesn't >create problems with the plated through holes.) > >The next step is imaging and how that is done depends on the required >quantity and line density. What I used (prototype/short run shop) was use >dry film. The board is cleaned and laminated with a photosensitive film. The >artwork was transferred to diazo film, and the diazo films were used to >actually image the board. At this point, the board is developed and the >copper you see is what you want. > >The rest of the process is fairly short. Electroplate copper up to the >desired thickness, electroplate tin-lead, strip the dry film, etch, gold >plate the fingers if necessary, fuse the tin-lead into solder, route, clean, >and ship. The etching is usually done by machine using an alkaline etching >solution. > >Doing the process at home can be done with a minimum of equipment if service >shops are used for parts of the process. A small copper plating tank, >tin-lead tank, and peroxide-sulfuric etchant along with fusing oil and flux >can be set up at home for probably a couple hundred dollars. To set up a >fairly complete shop including drilling and imaging would probably cost >between 2K and 3K. This would provide the capabilities of producing >reasonably high quality boards. Oh, did I forget to mention getting the >experience to know how to do it :)? > >BTW, I think you just meant dry film above. Dry Film Solder mask does >require UV curing and is probably impractical for home use. However silk >screening the soldermask and legend is easy and inexpensive to do at home.

25 years, 1 month

gauging interest in VAX 6000-530

by allisonp＠world.std.com

<It states: "The VAX 6500 processor delivered approximately 13 times the <power of a VAX-11/780 system, per processor." Your confusing the price of bricks with the weight of concrete. The MIPS metric is not accurate, I don't know if there is one. Further VAX doesn't spend all its cycles doing drystones. In the real world you do some math then do a LOT of housekeeping. <To me, that means "13 MIPS". 13 MIPS is about 2 to almost 3 times slower <than a 486dx2/66. Until you fill memory. then the contest reverses. The 486s of the time were doing good at maybe 5meg bytes/sec and thats SLOW. The real test then and now is what the system does with relational database of say 100mb is size. < CPU MIPS MIPS < System OS CPU (MHz) V1.1 V2.1 < ---------------------- ------------ ----------- ----- ------ ------ < VAX 8650 4.3 BSD ----------- 18 6.3 6.2 < cc -non_shared -DUNIX -O5 -ifo It's a non compare as an 8650 is not a 6000 anything. there are differnet memory bandwidths and IO bandwiths in effect and the slowest is much faster in action than an 8650. <And, back of the envelope, the 6500 was 2x the 8650. And it was 1/5 the volume. <I don't know what it is about collectors that somehow confuses their <memories of the past; maybe their internal core memories have suffered som <bit flips? ;-) (I have some old junk, too, so I consider myself in the <same camp...) Well, first of I'm not your average retrorevionist PC collector. I worked for DEC for 10 years (83-93) spanning the era in quesiton. <Fact is, these old machines were slow, noisy, hot, power-guzzling behemouth <compared with what we have today. Yes. Compared to the "hot" 486dx/50 in 1992 we were using the little (they are 10wx4Hx16D) VS3100s (same size and lower power than your power guzzling PC) as the PC crusher and those were typically 2.4-3.5VUP range. Oh, and I've used a VS3100 recently as a server at work for test purposes and the 3100/m10E clobbered the P166mmx/scsi box running NT. <As you know, the vax would run the X -client- which, of course, is not <much of a load. And as for running 50 users, heck, at the VCF 3.0 there <was a guy showing an 8080 running timesharing on a bunch of terminals! Yes, I know and have done. I've tried to run a p133 as a unix host (not a web server) as a timeshare client and it doesn't load as well as the VS2000 I have. The 8080 timeshare FYI had terrible latency! <Therefore, to me, you have to measure the performance in some repeatable <way. Dhrystone is not the perfect benchmark (which is close to an oxymoro <anyway), but it is -a- benchmark for integer CPU performance. Yes so... When I'm running a relational database that number means absolutly nothing. Running a word processor it's means nothing. <It's too bad that you had to run w3.11; I'm assuming you're running a real <OS on the dx2/66. In 1993 what real OS would have a PC running? DOS? Concurrent dos, SCO unix? Venix? The hot IO interface was 10b2 and AHA5142 SCSI. The really hot box was the 4cpu (486dx/50) box NCR made, there was no real OS yet and w95 was still beta testing on that box. <Now, let's talk about busses. Just how fast -was- this CI? Let's compare <that with 66 MHz 64-bit PCI, which has 66e6 x 64 = 4,224,000,000 bits/sec <peak throughput. What was CI's throughput? CI, cluster innerconnect was was fast when PCs were running ISA-16. If memory serves it was a 24-32mbytes/s rate. PCI-66 is now, and slow Alphas use it. The difference is you could have multiple CI busses and sorry but, only one PCI. Also PCI is not that fast. It's bursty and can run peak rates that fast but what is the CPU doing when PCI is honking at that rate? Answer? WAITING, if your real lucky running from the cache! But then when VAX was running CI what was the PC running? OK ISA-1 at some 8meg bytes/sec and memory interfaces were typically 70ns 32bit wide non-interleaved with caches. SCSI was maybe 10mb/s. the less than popular MCA bussed IBM hardware were much fast than the ISA and VL bussed counterparts. Running VMS in the early 90s we had SMP that was scaleable using LAVC (cluster over eithernet) and CI. There were also the BI and other interconnects. The point being your trying to save your arguement with _now_ hardware against _then_ hardware. PCs with then hardware were the industry joke for uptime, reliablility and performance, the AS400s, VAX, Prime, and others were the systems choice for getting work done on the larger scale. PCs in many ways are still behind the "big iron" of the early 90s, as they still lack a really good OS (linux, freebsd are contenders though). The hardware is not mature, they keep creating new standards that barely get debugged before they are pass`e. It's always amazing to see older systems bumping along getting real work done, usually while the PC user is rebooting for the third time today. Allison

25 years, 1 month

IBM 5155 Anyone have one?

by SUPRDAVE＠aol.com

In a message dated 10/25/99 4:05:18 AM Eastern Daylight Time, mikeford(a)socal.rr.com writes: > >Hi! > > > >Does anyone have an IBM 5155 (I think I got the model right) Portable PC > >that they would want to sell/trade something for? > > You mean a 5140? > well, its all semantics ,but the 5155 is called the portable pc and is a big suitcase sized machine. the 5140 is the covertible dual floppy laptop. d DB Young Team OS/2 --> this message printed on recycled disk space view the computers of yesteryear at http://members.aol.com/suprdave/classiccmp/museum.htm (now accepting donations!)

25 years, 1 month

gauging interest in VAX 6000-530

by allisonp＠world.std.com

<That's fascinating. Take obsolete hardware and architecture (vax), and Define that, obsolete is when it doesnt do the job. <>The problems is equivalent hardware. You can't configure a PC <>like a VAX, they are two different types of machines. A PC <>is tuned for a single user, while a VAX is tuned for many users. < <Amen! Thank you! You obviously didn't understand, likely don't care to. One observation is those that claim a narrow pardigm often end up eating it. VAX is not beall but then again it represents 20 years, in excess of 8 busses (cpu to memory and primary IO) and one major OS that still is secure and fast. PCs are an evolving species and wer are not up to the maturity level for even the OS not minding the hardware. <Remember, I was just making the observation that the integer performance of <the vax 8650 is worse than a dx2-66. I think single-user; I run single-use <machines. The future is single-user with vast network-accessed databases. All served by big iron with 64 bit cpus, why is merced so hot to beat Alpha. <Again, with -equivalent hardware- it certainly would. Ok. find a PC that you can cluster. Set it up in minimal time using an out of box OS. <having given up on Big Iron. Also, the market sizes for IBM, HP, and Sun' <"big iron" exist specifically to be those back-room servers that can do lot <of disk I/Os per second (the web, eh?). Even the web needs lots of IO, and more every day. <BUT, I would like the Vax Lover Crowd to acknowledge that they integer <performance of their machine is pathetic. If that all you hang you hat on you win. Your still missing the point and most everything with it. <> Its not the speed <>of the individual bus, but its the number of busses. < <That's of course bull..... < <>The more busses, the more parallelism and the less waiting. < <-IF- the speed of the busses is high enough! They have to be very very fast and the system on the bus very very fast and then you still have bus bandwidth conflicts. Therein lies the truth, if someone delivers a PC that has multiple independent PCI buses that can run in parallel will you start claiming that is better? <>One <>fast bus works well until you want to do multiple things, and <>then it quickly becomes a bottleneck. < <Excuse me? Could you please back up this assertion with data? After all, <at -some- point, all these busses have to get their data into/out of the CP <right? And -that- is a "bottleneck" for sure... (Sure, you can have <channel-to-channel I/O, but most aps are not just shuffling bits.) How about channel to Memory where the cpu get and put most of it's stuff. Or one bus that serives slow IO and another that is for memory acesses for multiple cpus at full bandwidth.Anyone thats stuied computer design and not software engineering would have studied system design and bus throughput models. <Sure, but AGP is better than -no- AGP, and it does show that there are othe <busses available on a PC, yes? (Which was my original point.) NO! those busses cannot operate in parellel and they operate and the expense of each other. I'd add if you plug in a slow card the plug and pray hardware may configure to that slower card at the expense of faster ones around it. All said and in the end, we have a troll. Allison

25 years, 1 month

gauging interest in VAX 6000-530

by cem14＠cornell.edu

At 07:56 PM 10/24/99 -0700, you wrote: >Excuse me? Could you please back up this assertion with data? After all, >at -some- point, all these busses have to get their data into/out of the CPU, >right? And -that- is a "bottleneck" for sure... (Sure, you can have >channel-to-channel I/O, but most aps are not just shuffling bits.) Well ... I have some experience with high-speed switches and crossbars in parallel supercomputers (as a user). The fallacy in your thinking is that you believe that moving data around is not "processing". You still think that the real processing takes place only at the cpu. Matter of fact is that, in the real world, as data goes through each driver/buffer and process in the OS on its way to the process that will actually do something with it (i.e., actual "integer-op-related" cpu time) there are usually several large block transfers. If all of this can happen without hogging the cpu (and you need hardware to do it) you can bet that the corresponding machine will be many times faster than a machine with a PCI bus. I once read that the average number of moves for net data (after it is in memory) for data from input through tcp/ip stack through OS through application is on the order of 4.x ... I think in some Sun literature...

25 years, 1 month

OT: how big would it be? - PCBs at home

by edick＠idcomm.com

First of all, I haven't read ALL of this thread, but I recall Tony or someone else replying to him saying something about the method for making plated through two-sided boards in your home. I've never met anyone aside >from professionals with scads of equipment who could do that, but it seems to me that the method which was described to me was to start with bare fiberglass/epoxy panels, drill them, then apply a slightly conductive coating in liquid form which had to be forcibly dried (perhaps baked) before the resist was applied. The boards were then exposed, the films applied to registration targets on each side, to a powerful UV light, for which some prefer to use direct sunlight, and the boards subsequently developed, then etched. Has any of you ever encountered an approach to this that could be managed in the home environment with equipment costing, nominally, less that a k-buck or two and achieving nominally 10-mil traces with 8-10 mil separation or anything close to that? How about a dry-film solder mask? Please share your experience, real or semantic. Dick -----Original Message----- From: Roger Merchberger <zmerch(a)30below.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Sunday, October 24, 1999 5:21 PM Subject: Re: OT: how big would it be? - PCBs at home >On or about 07:15 PM 10/23/99 +0100, Tony Duell was caught in a dark alley >speaking these words: > >>Oh, don't get me started on trying that... And that toner-transfer film >>isn't that good either... > >Isn't that good? My, you're certainly in the mood of understatement today, >Tony. I've tried that stuff (thinking... This is cool. I can finally >prototype PCB boards for my classic interfacing projects relatively >easily...) and I can officially say that it really, really, really sucks. >And the worst part? It's not that cheap, either. > >(certainly affordable, if it worked... which it doesn't.) > >For the problems with acetate, try getting a transparency film designed for >the actual printer that you intend on using. Toners are quite different, >including their fusing temperatures, fineness, and other factors. Another >thing to watch for with this iron-on crap (or laser film, or whatever): >Don't run it thru the printer twice. The high fusing heat changes something >in the media that seems to make it right close to worthless the 2nd time >round. > >I think that's what happened to me; the 600 DPI HP's use a "micro-toner" >which fuses at a higher temperature, and I think it changed the media so it >wouldn't "iron-on" easily, not to mention I don't think the iron got hot >enough to xfer the toner if that's a factor on the process working right. > >Some of the newer "photo" inkjets might work pretty well for artwork, >too... My wife's Epson Photo 700 does this thing called "micro-weave" for >the photo papers. It essentially takes 1/4 swipes at the image, and prints >the image 4 times at 1/4 density with the full printhead, so there's >virtually no banding. I've not tried it (have a laser) but it just might work. > >As always, YMMV and all that... >Roger "Merch" Merchberger >===== >Roger "Merch" Merchberger -- zmerch(a)30below.com >SysAdmin - Iceberg Computers >===== Merch's Wild Wisdom of the Moment: ===== >Sometimes you know, you just don't know sometimes, you know?

25 years, 1 month

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test-drb October 1999