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Cray X-MP Simulator Resurrects Piece of Computer History 55

An anonymous reader writes "If you have a fascination with old supercomputers, like I do, this project might tickle your interest: A functional simulation of a Cray X-MP supercomputer, which can boot to its old batch operating system, called COS. It's complete with hard drive and tape simulation (no punch card readers, sorry) and consoles. Source code and binaries are available. You can also read about the journey that got me there, like recovering the OS image from a 30 year old hard drive or reverse-engineering CRAY machine code to understand undocumented tape drive operation and disk file-systems."
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Cray X-MP Simulator Resurrects Piece of Computer History

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  • Anonymous? (Score:4, Funny)

    by Jmc23 ( 2353706 ) on Wednesday June 26, 2013 @12:45PM (#44114281) Journal
    If you want to be anonymous, linking to your blog with your full name probably isn't the way to go!
  • For the complete simulation, you need to use a generator load tester to burn the 100 or so kilowatts that the machine used.
    • using 2 inch copper bars, connect to a bridge with stainless steel bolts and lockwashers. use anti-oxide paste....

      • by hamjudo ( 64140 )
        You need a 3 phase load. That is going to take some careful bolt placement to get the 3 phases matched.

        Remind me never to visit your neighborhood.

  • by Chas ( 5144 ) on Wednesday June 26, 2013 @12:53PM (#44114403) Homepage Journal

    No punchcard readers? OMGWTFBBQ!!111eleventy


  • by Anonymous Coward on Wednesday June 26, 2013 @12:56PM (#44114443)

    if SGI wouldn't have deliberately destroyed all the old documentation and software when they bought Cray.

    • by Anonymous Coward

      Not to mention that it would be a whole lot easier to preserve the equivalent SGI mainframes via simulation and emulation if SGI would actually release their old internal documentation on the systems' chipsets. It's not like they're even making MIPS boxes anymore...

  • by Sponge Bath ( 413667 ) on Wednesday June 26, 2013 @12:56PM (#44114449)
    The plush toy in the photo makes the computations go faster.
  • by Anonymous Coward

    There are a bunch of other old computer emulators around such as the IBM 360/370/380/390 on which you can run OS\360, MVS and some other IBM OSes

    Also the TI990 minicomputer with the DX10 OS here

    It is great that people are preserving these things so that programmers of the future will have a chance to experience how things were in the early days. When you see the limitations that programmers had to work with,

    • by mendax ( 114116 ) on Wednesday June 26, 2013 @02:19PM (#44115447)

      A favorite is an emulation of another of Seymour Cray's earlier designs, the Control Data 6000 series monsters from 1964 and its successors the Cybers [], complete with screen shots [] of its then innovative console. I'd love to have this running on my iMac. I still have a copy of the old MIT Adventure game in FORTRAN for these beasts from my college days I wish I could play again. I'm too lazy to try to port it over to something else or get it to compile in a more modern FORTRAN compiler. However, the emulator does not include a copy of the NOS 2 dead start tape.

      • Control Data 6000 series monsters from 1964 and its successors the Cybers [], complete with screen shots [] of its then innovative console.

        I had to take a semester of assembly language at college. The choice was a PDP-11 in the CS lab (sign up, lowest priority for time => late nights and weekends) or one section that would learn CDC6600 (Cyber 74) assembly. Guess which one I picked? :-) I have totally forgotten all I learned, but it sure was fun while I was doing it!

        // eyes, lunar lander and baseball game on the dual vector displays

      • The MIT adventure game is on just about any freenix machine. It's part of the 'BSD Games' package on Slackware (at least it was on the last version I used) and is a default part of the system on NetBSD (the 'adventure' program in /usr/games). It would be a little silly to re-port it yet another time.

        Don't forget to pick up the lamp before typing 'xyzzy'

  • by peter303 ( 12292 ) on Wednesday June 26, 2013 @01:34PM (#44114927)
    and would it be faster than the original?
    • by EGSonikku ( 519478 ) < c o m> on Wednesday June 26, 2013 @02:36PM (#44115637)

      Considering the original Cray XMP ran at 105MHz and had 16MB RAM, yes. But in 1982, those specs were just wildly insane.

      • by Rich0 ( 548339 )

        The 105MHz is a bit deceptive in that this thing probably had much higher memory/IO/etc bandwidth and vector capability compared to a traditional desktop of that era running at that speed.

        I'm sure it still isn't that hard to emulate today, but the performance of the Cray shouldn't be dismissed out of hand with the clock speed.

        • Ya this was vector design, which was a massive pipeline thing, akin to an assembly line with stages. The ends, and overhead were no great shakes, but once it churned on a long batch of numbers, boom!

          The question is valid though. IIRC, in the late 90s, high-end PCs were about equal to the first Cray.

        • The 105MHz is a bit deceptive in that this thing probably had much higher memory/IO/etc bandwidth and vector capability compared to a traditional desktop of that era running at that speed.

          According to this popular mechanics article from 1982 [] the top 6 home computers were the IBM PC, the TSR-80, the Apple II, the Atari 800, the Commodore PET, and the TI 99/4a. The IBM PC ran at 4.77 MHz. If I recall correctly , "wait states" also played an important role-- something that Cray would have avoided.

          Then again, personal computers were designed to be affordable. Minicomputers, workstations and mainframes were quite a bit faster.

      • The Cray XMP-48 had up to 1 GB of RAM. That RAM subsystem was bigger than the CPU core. Apple had one back in the early 90's
        250K watts 230 tons including its cooling system. IT was fed data and storage from a herd of VAX 11/780s with wash-tub sized HD units. The residential neighbors to that building had lots of complaints about lights dimming when that machine started burning midnight oil.

  • Sweet! (Score:5, Funny)

    by Nidi62 ( 1525137 ) on Wednesday June 26, 2013 @02:13PM (#44115397)
    Now I can sequence that old dinosaur DNA I got from this chunk of amber sitting in my closet!
    • Joke I know, but couldn't resist a geek nitpick: weren't the supercomputers in Jurassic Park Thinking Machines what with all their awesomely photogenic blinkenlights?

      IIRC they used a Cray (XMP? YMP?) in Sneakers. I remember Ben Kingsley making a big deal of sitting on a red one, so I think it's a YMP. Still one of my favourite "Hollywood Hacking" movies as it bears a passing resemblance to reality. [] []

      • by Nidi62 ( 1525137 )

        Joke I know, but couldn't resist a geek nitpick: weren't the supercomputers in Jurassic Park Thinking Machines what with all their awesomely photogenic blinkenlights?

        You are correct in regards to the movie, but the book specifically states that they used 2 Cray XMPs to run the Hood sequencers. Trust, I am currently rereading the book :)

      • by Burdell ( 228580 )

        The color of a Cray doesn't tell you the model; you could get them in different colors. NASA's were "NASA blue" for example.

  • by Bearhouse ( 1034238 ) on Wednesday June 26, 2013 @02:23PM (#44115499)

    You will probably realise you're not even close. This is truly nerdy, and I love it.
    Stuff like this makes putting up with all the daily bitcoin etc crap worthwhile.

    • From the article, "I’ll only leave some of the most spectacular failures in for entertainment value."

      Beautiful. Reminds me of a test pilot of yore at Edwards, "In spite of all the damn fool things I did, the plane managed to land itself."

      A truly nerdy project done by a true nerd. Bravo.

  • I hope he sends a copy to the Computer History Museum. They already have an operational Babbage Difference Engine and a PDP-1. A Cray would be very neat. For extra credit, he needs to find the SE Test Pack...that should have all kinds of neat code on it.
    • by crgrace ( 220738 )

      The Computer History Museum already has a few Crays (including the mythic Cray 3), but it would be cool if they could add this emulator to their library.

  • Can't anyone cough up some disk images for this guy, or are copyright issues the crux of the matter? Admittedly, even though it doesn't do much other than boot up, it is still so very cool.

    John Francis

  • I saw X-MP and immediately thought they had a Cray simulate an XMP burst, and I rushed to open the article and read all about the latest #ingress news.

    Now I realize ... I have no life!

  • This area produced Plutonium for nuclear weapons; supplying the fuel for the Trinity and Fat Man atomic bombs.
    Plutonium production continued up to the late 1980's (or until Chernobyl); for peaceful purposes of course.

    The Hanford project as it was called; long as I can remember they had a small museum explaining the project.
    When they moved it from the recreational area (original location) to the the Federal Building a few Cray computers were added and used
    as seating areas. A small sign near them saying they were Crays but just circular seating if anybody needed to rest.

    I had a friend who programed the Cray's, sometimes he would call just to chat; but it could be a problem. He would always be near the cooling system
    so his phone had a receiver cut off button. He'd say something then hit the button so the cooling system wasn't heard in the back ground making
    a conversation possible. I don't know if he called on his rounds or he was located next to the coolers, but they were loud.

    At one of the Government auctions I had a chance to bid on and even of purchased a Cray, but it would be spendy as junk goes.
    An old Univac system was once auctioned (I thought about bidding on it - it would of taken up the entire house and a good part of the yard :} )
    never met it's lowest bid due to the precious metals involved.

    A Cray computer in my house, I imagine I'd of used it as a dysfunctional couch as well, but a hell of a conversation piece.

    I had a storage shed that was the wooden box shipped box for some multi million computer, lots of great stuff could be scavenged in this area while D.O.E.
    was spending money.

    *Many key words were used here, Hello again NSA.*

No amount of careful planning will ever replace dumb luck.