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Big Mac Benchmark Drops to 7.4 TFlops

coolmacdude writes "Well it seems that the early estimates were a bit overzealous. According to preliminary test results (in postscript format) on the full range of CPUs at Virginia Tech, the Rmax score on Linpack comes in at around 7.4 TFlops. This puts it at number four on the Top 500 List. It also represents an efficiency of about 44 percent, down from the previous result of 80 achieved on a subset of the computers. Perhaps in light of this, apparantly VT is now planning to devote an additional two months to improve the stability and efficiency of the system before any research can begin. While these numbers will no doubt come as a disappointment for Mac zealots who wanted to blow away all the Intel machines, it should still be noted that this is the best price/performance ratio ever achieved on a supercomputer. In addition, the project was successful at meeting VT's goal of developing an inexpensive top 5 machine. The results have also been posted at Ars Technica's openforum."

4 of 417 comments (clear)

  1. Too good to be true... by mrtroy · · Score: 5, Insightful

    That 80% efficiency simply sounded too good to be true, and it was.

    Now its at 44%. Thats not a small drop, thats a MASSIVE drop.

    They didnt predict any loss in going from a small subset to the whole system? Or was it a publicity stunt (we can outperform everyone! our names are __________!)

    --
    [I can picture a world without war, without hate. I can picture us attacking that world, because they'd never expect it]
  2. This is NOT all that surprising. by dbirchall · · Score: 5, Insightful
    A single G5 FPU (each CPU has 2) can do 1 64-bit (double precision) FLOPs per cycle, or 2 if and only if those two are a MULTIPLY and an ADD.

    Apparently there are a lot of cases where a MULTIPLY and an ADD do come together like that, but I'm not surprised if LINPACK doesn't consist entirely of those pairs. ;)

    The 17.6 TFLOP theoretical peak assumed a perfect case consisting entirely of MULTIPLY-ADD pairs. In a case assuming no MULTIPLY-ADD pairs, the theoretical peak is 8.8 TFLOPs.

    7.4 TFLOPs is only 42% of 17.6 TFLOPs, but it's 84% of 8.8 TFLOPs. I suspect the actual "efficiency" of the machine lies somewhere in the middle.

    (As for me, I'm happy with just ONE dualie...)

  3. They didn't save the world AGAIN? by ianscot · · Score: 4, Insightful
    Yet another Apple product that failed to save the world. Lately they do nothing but disappoint us. Boo.

    First you have the iTunes store which doesn't do anything but give the average user basically anything he or she might have wanted to have in on online music store. Despite its being free, we're all cheesed off that it doesn't support OGG, or it's meant partly to push iPods (duh), or whatever.

    Now this -- a supercomputer that has, to quote that again, the "best price/performance ratio ever achieved on a supercomputer." But dang it all, it doesn't completely blow away every established precedent -- it's just in the top five on the usual list of comparisons. One more crushing disappointment.

    From Microsoft, we just want products that don't completely ream us. From Apple, we want the entire world to seem a little friendlier and cooler with every product release, every dot-incremenent OS update. They both disappoint us, but the expectations seem a little different...

    --
    "Fundamentalism" isn't about divine morality. It's about human authority.
  4. Re:Important items of note by Durinia · · Score: 4, Insightful

    On the other side of the issue is that it places 4th in the current Top 500 list, which was released in June. We won't really know where it places on this "moving target" until the next list is released in November.