nash@ucselx.sdsu.edu (Ron Nash) (02/24/90)
I am throwing this to the collective net wisdom (:-). I am asking for suggestions and any experiences good or bad to guide us in our search. The main uses of the computer will be teaching Unix and programming, and research. We have Macsyma and Lisp users and neural-network research that can be quite a drain. We are looking for a Unix engine that will support at least 100 concurrent users. It would be nice if it could be expanded to support more users if needed. The Unix should be BSD or be BSD compatible. A major concern is compatability of BSD software. Please post or email. If there I get or see requests for a summary, I will post a summary of the responses. If you want any more info from me, please let me know. Thanks in advance! -- Ron Nash San Diego State University Internet: nash@ucselx.sdsu.edu UUCP: ucsd!sdsu!ucselx!nash
neil@uninet.cpd.com (Neil Gorsuch) (02/25/90)
In article <long-id@ucselx.sdsu.edu> nash@ucselx.sdsu.edu (Ron Nash) writes: >I am throwing this to the collective net wisdom (:-). I am asking for >suggestions and any experiences good or bad to guide us in our search. >The main uses of the computer will be teaching Unix and programming, >and research. We have Macsyma and Lisp users and neural-network >research that can be quite a drain. >We are looking for a Unix engine that will support at least 100 >concurrent users. It would be nice if it could be expanded to support >more users if needed. The Unix should be BSD or be BSD compatible. A >major concern is compatability of BSD software. Here's one way to do it that will definitely save you big bucks. Instead of buying a single BIG machine for a BIG price, look to where the best deal is in (MIPS+Mbytes/$), which is currently desktop workstations, and buy some of those, TO BE USED AS MULTI-USER MACHINES. For instance, how about using 10 Sparcstations (or substitute your own favorite brand) as multi-user machines. Actually, I would only put in 5 and put 20 users per machine, but you might want to be more conservative and put in 10 with 10 users each. If you make each one a "dataless" client of an appropriate server, you will have a VERY peppy 10 (20) user machine. There's a nifty way to add a bunch of serial ports to desktop workstations without using the ethernet, so that shouldn't be a problem. Each Sparcstation is 12.5 MIPS or so, can have up to 64 Mbytes of memory, can have Gigabytes of 16 mS disk storage, and is BSD ported/compatible, so they should handle your needs. And with recent/upcoming announcements, you will probably be putting in 27 MIPS machines instead of 12.5 MIPS machines if you wait a few months 8-). Personally, I would even skip the server and sprinkle the user's files amoungst the workstations, with various NFS cross-mounts, while making sure to put as many user's files on the workstations that they mostly log onto as is possible. You should be able to do that with a lot of the students and most of the professors. You can be very creative in how you cross-mount user's home directories, while still backing everyone up each night over the network with a few Exabyte tapes. The entire "system" will be much more reliable, since you will have a number of machines so that one machine going down will not cripple all of your users. With the money that you save on a maintanence contract for a big machine, you could even have spare workstations lying around, and have users files duplicated on more than one disk, with automatic nightly duplication, so that in the event of a disk or workstations crash you could just switch around your NFS mountings for fast "repair". The system is very easily expandible, just add more workstations. In the case of the Sparcstations, you can even have 2 ethernet interfaces in each for ease of networking configuration. When researchers clamor for a workstation instead of a terminal, you can accomodate them without bogging down your primary "system" ethernet backbone by putting the private workstations on a second ethernet interface in the workstation that was their "login" computer. -- Neil Gorsuch INTERNET: neil@uninet.cpd.com UUCP: uunet!zardoz!neil MAIL: 1209 E. Warner, Santa Ana, CA, USA, 92705 PHONE: +1 714 546 1100 Uninet, a division of Custom Product Design, Inc. FAX: +1 714 546 3726 AKA: root, security-request, uuasc-request, postmaster, usenet, news
long@castor.csg.uiuc.edu (Junsheng Long) (03/03/90)
I would like to know the data segment layout of a C program on Unix (Sun OS). For the following example, I found some extra variables were inserted before the first global variables (marked as ? in the following figure). /* --- example.c ---*/ +----------+ int a = 0; | text | int b[32]; +----------+ <- etext | ? | main() +----------+ { | a | ... +----------+ <- edata } | b | +----------+ <- end | | Now my questions are: does anyone know what they are? Does they vary from program to program? Thank you very much. junsheng long
nash@ucselx.sdsu.edu (Ron Nash) (03/07/90)
> I am throwing this to the collective net wisdom (:-). I am asking for > suggestions and any experiences good or bad to guide us in our search. > The main uses of the computer will be teaching Unix and programming, > and research. We have Macsyma and Lisp users and neural-network > research that can be quite a drain. > > We are looking for a Unix engine that will support at least 100 > concurrent users. It would be nice if it could be expanded to support > more users if needed. The Unix should be BSD or be BSD compatible. A > major concern is compatability of BSD software. > Here is the summary of responses. Convex 1, Dec 1, Encore 1, Mips 1, Sequent's Symmetry 7, Pyramid 2, and two people are still looking. I would appreciate any additional comments. Thank all of you that responded! It has been very helpfull. -- Ron Nash San Diego State University Internet: nash@ucselx.sdsu.edu UUCP: ucsd!sdsu!ucselx!nash ############################################################################### We've been shopping recently for machines to replace our now-outdated VAX 8650's. This is what we've been looking at: Solbourne 20+ mips/processor, 4 max. Fast IPI disks on the way soon (can't give you figures, sorry). Just announced 40 mips/processor later this year. Sun 20+ mips - IPI disks now. MIPS 55 mips for their new ECL machines. Pyramid Current crop of machines based on a dual sysV/BSD universe and on the proprietary Pyramid processor with 9+ mips/processor, 14 max. Design is good, but on the way out. Other machines based on MIPS chips with 20+ mips/processor available in 4th quater. You might also want to look at HP and Silicon Graphics. Good luck. --- Name: Christopher J. Calabrese Brain loaned to: AT&T Bell Laboratories, Murray Hill, NJ att!ulysses!cjc cjc@ulysses.att.com Obligatory Quote: ``Anyone who would tell you that would also try and sell you the Brooklyn Bridge.'' ############################################################################### We are looking for the same kind of thing. At the moment, we are considering: Multiflow Trace 7/300 Encore Multimax (model 520, I think) DEC 5400 (2 of them, I think) Solbourne ??? MIPS RC6280 Sun 4/490 SGI Iris 4D (4 cpus) IBM RS/6000 530 The list is ordered from most to least BSD-like. We could live with anything above on the list above the SGI; it and IBM are too much SysV. I would be interested in any other information you can gather. We have to decide what to buy within three weeks or so. We have some benchmarks on some of these boxes. I will mail them to you if you like. -Guy Middleton, University of Waterloo gamiddleton@watmath.waterloo.edu (+1 519 885 1211 x3472) gamiddleton@watmath.uwaterloo.ca ############################################################################### Tough question, since most of the really big iron has a sysV fixation. The apps you mentioned are not floating point intensive, more on the symbolic side. I think you need something like a 4 cpu Solbourne or a ... uhm .... who is it that makes the vliw box? darn... Anyway, something like that with an FDDI link to your disk servers, say 3 or four sun4s. Put this monster in the center of your network as a cycle server and scatter smaller boxes -- sparcstation1s or something -- around for interactive junk. put the users on X terminals with their default sessions on the satellite cpus, have the cpu-intensive programs automagically run on the cycle server. -- Steve Nuchia South Coast Computing Services (713) 964-2462 "You have no scars on your face, and you cannot handle pressure." - Billy Joel ############################################################################### We have also just started a search for a similar box, so I would be very much interested in seeing a summary posted. We are currently looking at Convex (the "air-cooled Cray"). They have expandable models and are claiming POSIX compatiblity, rather than BSD or SYSV. Their compilers supposedly can vectorize and parallelize to take advantage of multiple processors. In the next week or so we will give them a number of programs/data-sets which they will run on different models with and without the vector/parallel options. Other features are high disk transfer rates and I/O processors (which they claim allows support of large numbers of interactive users). As may be obvious, the above info is from Convex's sales/marketing folks, so I am definitely interested in less biased opinions on the capabilities and reliability of this box and anything similar. -- Joe Hamlin <hamlin@blackbird.afit.af.mil> ############################################################################### Looking for a bix UNIX box ? Look at the DEC 6000 series machines. Wonderfull boxes, love them..can't say enough good about them, and I don't work for DEC. (or have much to do with them them either, just use the equipment...) Peter Theune. Johns Hopkins University, the Applied Physics Laboratory ############################################################################### You should probably speak to Encore for a configuration of that size. Boston University ... department of Computer Science has an installation fairly similar to what you describe. Encore builds MIMD parallel processors, which means they are sort of like Vaxes or other minis except that can have 2-20 CPUs (current architecture, 40 on their next system.) The CPU boards each have 2 CPUs. The company was founded by, among others, Gordon Bell who led design for, well, most of the systems DEC has produced in the last 30 years (PDP-10, PDP-11, Vax.) Rumor had it that the Encore was his design for the next generation of Vax but DEC wouldn't go for it, so he pulled Encore together. But that's just rumor. Their current system is based on the NS32532 which is about an 8 MIPS CPU, so the MIPS range is 16-160. To be honest, it's difficult to put 20 CPUs into their box although 16 should be fairly easy (the problem is just that memory goes in the same slots and there's some natural growth of memory for time-sharing systems as you add CPUs, not much of a limitation, 16*8 = 128MIPS.) Note that all MIPS ratings of course are aggregate. The system can be bought with either Mach, BSD or SYSV. I'd strongly recommend either Mach or BSD. Their Mach is being adopted for OSF's OSF/1 operating system release, so I would recommend looking very closely at Mach. They plan to move to the Motorola 88K, probably Mach will be the first release (ask them.) If I can be of any further assistance don't hesitate to get in touch. -Barry Shein Software Tool & Die | {xylogics,uunet}!world!bzs | bzs@world.std.com Purveyors to the Trade | Voice: 617-739-0202 | Login: 617-739-WRLD ############################################################################### Although neither is really available yet, I recommend the MIPS R6000-based box running 4.4BSD. Chris ############################################################################### Make sure you look at Sequent's Symmetry line. We have Dynix 3, a BSD 4.[23] port of UNIX, and Dynix/PTX, a SysV.3 version. It's all based on 80386 (ask them about 80486 if you care, though :->) processers, and the OS runs symmetric multiprocessing. The nice part about it as compared to discrete workstations of some sort is that on an idle system a single user gets the benefit of a whole lot more horsepower than any single workstation user is going to get. I can get our sales office to give you a call if you'd like. So much for my biased point of view. I hope I've at least interested you enough to take a look! Regards, Andy Valencia Dynix 3 kernel group ...!uunet!sequent!vandys ############################################################################### Take a look into getting a Sequent Symetry (one of our machines is an S27, purely development). It runs DYNIX which is sortof 4.2 level and allows you to use System V2.0 utilities if you choose. You can choose to be in either the bsd "universe" or att "universe." I have compiled a couple of large sources for bsd machines and had no difficulties, whatsoever. It is _supposed_ to be fully bsd'ish. As to power, you can put in up to twenty processor boards, each of which has two parallel 80386's. The text segment for the kernel is shared, they each have their own data segment and use semaphores and whatnot for synchronization. They are becomming quite popular with travel agencies (big, big, not boiler room, mind you). They run on a multibus, but you can use SCSI peripherials (standard if you buy it from UNISYS, I don''t know about from Sequent). It is a very fast and does not take up alot of space. The base unit is about 3.5'x3.5'x3.5'. The expansion cabinet is supposed to be a little bigger. The nifty thing is that you can let your students do driver work for a single processor environment, and then turn around and have them make the same driver work under parralel processing (they will love you for this :-) ). cbp ############################################################################### I suggest a Sequent symetry system like this one... System Configuration: type no slic flags revision MEM/1w 0 2 00000000 00.03.02 size=40.0Mb base=0x00000000 ileave-lo MEM/1w 1 20 00000000 00.03.02 size=40.0Mb base=0x00000000 ileave-hi MBAD 0 24 00000000 00.05.01 f/w version=6 MBAD 1 26 00000000 00.05.01 f/w version=6 SCED 0 28 00000000 02.12.00 ver=42 host=71 enet=080047000fa8 local ZDC 0 34 00000000 00.02.00 f/w version=14 ZDC 1 38 00000000 00.02.01 f/w version=16 ZDC 2 40 00000000 00.02.00 f/w version=14 CADM 0 0 00000000 01.03.00 sysid 0x000231 front panel type 0 PROC/386w 00000000 00.06.01 16MHz 2*32K FPA: no. 0(slic 4), 1(5), 2(8) PROC/386w 00000000 00.06.01 16MHz 2*32K FPA: no. 3(slic 9), 4(12), 5(13) PROC/386w 00000000 00.06.01 16MHz 2*32K FPA: no. 6(slic 16), 7(17), 8(18) PROC/386w 00000000 00.06.01 16MHz 2*32K FPA: no. 9(slic 19) [ Thats, 10 CPUS, 10 floating point units, 80Mb memory, 3 disk controllers ] We can put ~320 users on it all doing things.... kayessbee -- Lightning strikes! Maybe once, maybe twice. Oh, and it lights up the night! Kevin Braunsdorf, ksb@cc.purdue.edu, pur-ee!ksb, purdue!ksb ############################################################################### Look into Sequent. My company looked at them, but didn't have large enough processing needs to justify one. They are parallel Unix (Dynix) boxes capable of supporting 8 to 1000 users on from 2 to 30 80386 tightly coupled processors. What a Machine! -- Dewey Paciaffi eddjp@althea.UUCP ############################################################################### I'm not so sure a big central machine is the way to go for LISP and MacSyma users but; This machine (a Sequent) keeps about 100 rn users happy (I have yet to see it slow down). Not cutting edge and not straight BSD but it does seem to take a lot of I/O processing well. In an environment such as you describe I'd guess a cluster approach (where several identical processors share a common set of drives and each new process (or at least; each new user) gets thrown to whatever processor is least loaded at the time would be a reasonable approach. -- -dave fetrow- fetrow@bones.biostat.washington.edu dfetrow@uwalocke (bitnet) {uunet}!uw-beaver!uw-entropy!fetrow "CP/M: Remember when fast, small, useful and clean were good?" ############################################################################### Burlington Coat Factory has bought 4 Sequent Symmetry machines, and we're VERY happy with them. (We started out with 1, and liked it so much that we bought 3 more). Sequent's boxes are (coarse-grained) parallel processors. You can plug in more processor boards as system load increases. Our biggest machine has twenty '386 processors, and supports 200 users without even slowing down. (Right now we have 110 users coming in over an X.25 switch, and 30 more through telnet, and the machine is only using 20% of its processors). Parallism comes "for free" when a process forks. If you pipe the output of one program into the input of another, both programs will execute *simultaneously* on different processors. The operating system is dual-universe (like Pyramid) -- so you get your choice of BSD or SysV. The underlying kernel is BSD. We've never had any problems porting programs; they usually compile without modification. (The kernel is derived from BSD 4.2, not 4.3, if that's an issue). Call me if you have any questions you'd like to ask. -- "Live justly, love gently, walk humbly." Andy Behrens andyb@coat.com or: andyb%coat.com@dartmouth.edu or: {uunet,rutgers}!dartvax!coat.com!andyb Burlington Coat, HCI 61 Box 1B, Lebanon, N.H. 03766 (603) 448-5000 ############################################################################### You might want to check into Sequents. We have a Sequent Symmetry with over 200 logins, maybe 100 or so active at one time, plus at least one large database crunching away constantly, and the highest I've seen the load get is 2, when someone in QA fired up about 15 compiles in parallel, at the same time that someone had started up a second database. Happy computer hunting! --woodstock -- "What I like is when you're looking and thinking and looking and thinking...and suddenly you wake up." - Hobbes nhess@oracle.com or ...!uunet!oracle!nhess or (415) 598-3046 ############################################################################### Consider a system from Pyramid Technologies. We have an early 90x and it is a rock: with a single CPU configuration and about 30 users average we have had essentially no unscheduled downtime for almost three years. Their new MIServer systems can be configured with from 1 to 12 12 VUPS CPUs so the system has room to grow. The I/O controllers have a lot of smarts so they offload quite a lot of processing from the kernel. They have a "dual universe" system which is really BSD but provides a very handy and complete SysV environment (we use BSD almost exclusively except to compile SysV sources, which we then install under the BSD universe). UCSD has a bunch of them but the biggest local installation of the latest Pyramid models is a PacBell. Jerry -- / Gerald Hall, UNIX SysAdmin, (619) 587-3065 / Calma - A Division of Prime Computer Inc. / 9805 Scranton Road, San Diego, CA 92121 ############################################################################### I would suggest you take a look at machine by Pyramid Technology out of Mountain View, California, as well as those made by Sequent Systems out of Beaverton, Oregon. There are probably a few other manufacturers of such high-power, large capacity multi-user Unix systems. Maybe even the top end NCR Tower machines, and the similar top end machines from Unisys could handle that large a load, although both are System V oriented. Pyramid and Sequent both offer BSD compatible systems, I believe. I know Pyramid does. -- Chris Johnson DOMAIN: chris@c2s.mn.org Com Squared Systems, Inc. ATT: +1 612 452 9522 Mendota Heights, MN USA FAX: +1 612 452 3607 -- Ron Nash San Diego State University Internet: nash@ucselx.sdsu.edu UUCP: ucsd!sdsu!ucselx!nash