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Supercomputing Technology

The Problem With the Top500 Supercomputer List 175

angry tapir writes "The Top500 list of supercomputers is dutifully watched by high-performance computing participants and observers, even as they vocally doubt its fidelity to excellence. Many question the use of a single metric — Linpack — to rank the performance of something as mind-bogglingly complex as a supercomputer. During a panel at the SC2010 conference this week in New Orleans, one high-performance-computing vendor executive joked about stringing together 100,000 Android smartphones to get the largest Linpack number, thereby revealing the 'stupidity' of Linpack. While grumbling about Linpack is nothing new, the discontent was pronounced this year as more systems, such as the Tianhe-1A, used GPUs to boost Linpack ratings, in effect gaming the Top500 list." Fortunately, Sandia National Laboratories is heading an effort to develop a new set of benchmarks. In other supercomputer news, it turns out the Windows-based cluster that lost out to Linux stumbled because of a bug in Microsoft's software package. Several readers have also pointed out that IBM's Blue Gene/Q has taken the top spot in the Green500 for energy efficient supercomputing, while a team of students built the third-place system.
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The Problem With the Top500 Supercomputer List

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  • Quelle surprise! (Score:4, Insightful)

    by Elbart ( 1233584 ) on Friday November 19, 2010 @01:25PM (#34283128)
    Now that the Chinese are ahead, there's suddenly a problem with the list/benchmark.
    • Re: (Score:2, Insightful)

      by Daishiman ( 698845 )
      Agreed. It seems like the issue is "big enough" only now that other people are catching up.
      • by Z00L00K ( 682162 )

        And any number presented only has a meaning if it's applicable to the problem you have.

        If you have a problem that scales well to TPC-C it may be useless to go by Linpack numbers to find the solution you are after. And the other way around.

      • by natet ( 158905 ) on Friday November 19, 2010 @03:16PM (#34284360)

        Agreed. It seems like the issue is "big enough" only now that other people are catching up.

        I call bullsh*t on this comment. Around 8 years ago, the top computer on the list was a Japanese machine, and it rode atop the list for 3 years straight. Those of us who have worked in high performance computing have known for years that the top 500 list was a load of crap. It's something to write a press release about so that the people that give us money to build the big computers feel like their money is well spent. I worked on a top 5 computer at one time, but our focus was always the science that we wanted to do on the computer. Running the linpack benchmark for the top 500 list was an afterthought (though it was a pleasant surprise to score as well as we did).

    • Meh. Most of the computing world has confused speed for power for decades now, whether on the desktop, in the datacenter, or in most benchmarks. Any attempt to better quantify performance can only be a good thing. However, I share your skepticism of the timing.
      • It's not just this. These benchmarks are all just games, and people are powergaming the tests. Sure, the Chinese blew away this one specific test, but how powerful is that machine? IE9 cheated on SunSpider [slashdot.org] and got better results and better ad copy.

        What they have to do is come up with a new benchmarks each year. Have it based roughly on the old test so you know what's going to be tested but have different questions. Otherwise it'll be just like my classes at engineering school. Some students memorized l

        • Re:Quelle surprise! (Score:4, Informative)

          by KingMotley ( 944240 ) * on Friday November 19, 2010 @04:05PM (#34284922) Journal

          That makes a nice headline, but everything the article is based on has been proven to be untrue and sensationalist. My 8 year old son, when he lost, used to also accuse others of cheating as well. Usually he was wrong as well, but I didn't take his word for it and then try to pass off a news article on it.

          • Meh, I use IE7 at work and FF at home, so I didn't read into it.

            If it was some quirk of the test then I guess I owe MS an apology letter.

            • It is a bad test that did nothing useful. IE9 detects some simple cases where nothing is being done and skips it instead. Sunspider just happens to have a test that triggers it. It is a generic test, however, at the moment it is pretty primative but it will likely get better over time. Sunspider needs to actually do something with their results to prevent this from happening.

        • Some students memorized last year's tests and got artificially inflated grades. They couldn't figure out that e.g. 3.8V on the meter was, in fact, 4V when you add in the resistor tolerance.

          The easiest way to scramble questions is to use the same data structures you would use for sorting them.
          If you really want to mess things up, then scramble the answers.

      • by mcgrew ( 92797 ) *

        Most of the computing world has confused speed for power for decades now

        How is anything other than speed and storage "power" to a computer?

        • Speed boils down to cycles per second. Power is work over time. The megahertz myth is rooted in the ease with which the former mistakenly implies the latter. I've seen SPARC systems do more work than contemporary Intel systems, with the Intels running at a higher clock rate. Similarly, scoring high on one particular benchmark does not necessarily give a true indication of the actual power of this, or any other supercomputer.
          • by mcgrew ( 92797 ) *

            But if I've read the summary correctly, this doesn't measure clock speed, it measures the speed of actual, numerical, computer-intensive computations. A computer that can compute PI to the thousandth decimal in n seconds is twice a powerful as one that takes n*2 seconds. At least, for computing PI.

    • by Animats ( 122034 ) on Friday November 19, 2010 @02:14PM (#34283572) Homepage

      Yes, noticed that.

      Here's the actual benchmark used for Top500: [netlib.org] "HPL - A Portable Implementation of the High-Performance Linpack Benchmark for Distributed-Memory Computers". It solves linear equations spread across a cluster. The clustered machines have to communicate at a high rate, using MPI 1.1 message passing, to run this program. See this discussion of how the algorithm is parallelized. [netlib.org] You can't run this on a set of machines that don't talk much, like "Folding@home" or like cryptanalysis problems.

      Linpack is a reasonable approximation of computational fluid dynamics and structural analysis performance. Those are problems that are broken up into cells, with communication between machines about what's happening at the cell boundaries. Those are also the problems for which governments spend money on supercomputers. (The private market for supercomputers is very small.)

      So, quit whining. China built the biggest one. Why not? They have more cash right now.

    • by inhuman_4 ( 1294516 ) on Friday November 19, 2010 @02:54PM (#34284084)
      The Linpack complaining has been going on for years. I remember this coming up with the NEC earth simulator, and other ASIC based systems.

      Here are some interesting numbers:
      AMD Radeon HD 4870X2 ~2.4 teraFLOPS
      Intel Core i7 980 XE ~107.55 gigaFLOPS

      According to this the AMD is 20x faster then the Intel; and this is true, but only in some cases. If what is need is graphic processing the AMD will crush the Intel. But if you need anything else (I am ignoring GPGPU for simplification) the AMD doesn't just lose, it doesn't run. This is a problem for all ASIC based systems, GPU ones are just the newest to come out.

      So this new Chinese supercomputer (and other ASIC based supercomputers) score very high in Linpack because the ASICs are designed to be good at this type of task. This makes for a non-general purpose, but very cost effective solution.

      But this then means that a supercomputer that cannot use GPUs for its intended task, score very low because they are general purpose machines. Because the Top500 is based on one benchmark (Linpack) you end up with a car to pickup-truck comparison; sure the car is faster, but what about towing capacity?

      The end result is the supercomputer analog of the megahertz-myth, people like bigger numbers. A high score proves that is it faster at somethings, but not that it is faster in general.
    • your right. It takes some big metal to pump out the volume of ebay ads we have come to depend on here...They NEED a windows machine to do some critical MS Word grammar checking.
      XYZ Group is a global e-commerce leader and one of the largest e-commerce company in China. We manufacture present and jewelry have surpass 15 years history . Our unceasing improvement and enhances the product the quality.We have the confidence to do are better .Your request is our goal .
  • I have always wondered why being on the Top500 list of supercomputers that important for those on the list. I will be better served by being told the advantage(s) or edge those who've been on that list have gotten since they got onto the list. Thanks.

    • The advantage is that, contrary to the arguments of TFA, the test is very representative of scientific and engeneering problems. That way, if you want to be at the top at the available computing power, you'll very probably want to be at the top 500 list.

      • by natet ( 158905 )

        The advantage is that, contrary to the arguments of TFA, the test is very representative of scientific and engeneering problems. That way, if you want to be at the top at the available computing power, you'll very probably want to be at the top 500 list.

        Not necessarily true. It is representative of a CLASS of scientific and engineering problems. If the science that you want to run involves heavy use of vectors, then you want a computer that would be high on the top 500 list. Derivatives and integrals? Not as much. Problems that require a high degree of interaction between nodes? Get a computer with a faster interconnect. It all depends on the science you intend to do with that computer. The NEC Earth Simulator (mentioned in another thread) would do

      • by 1729 ( 581437 ) <slashdot1729 AT gmail DOT com> on Friday November 19, 2010 @03:54PM (#34284788)

        The advantage is that, contrary to the arguments of TFA, the test is very representative of scientific and engeneering problems.

        No, it really isn't. I work in HPC at a national lab, and our bureaucrats buy these computers based on these benchmark numbers and then expect us to adapt our codes to fit these machines, rather than buying machines that are better suited to the problems we are solving. For example, one of our machines peaked at #2 on the Top500 list, and was essentially useless for real codes. Another machine of ours held the #1 spot for quite a while, and worked well for a small class of problems, but was so limited in functionality that it couldn't even run many of our codes. I've heard similar stories from people using other machines near the top of the Top500.

        Real science codes often do not look anything like LINPACK, and the computers that run these benchmarks fast aren't necessarily good for true HPC.

        • Re: (Score:3, Insightful)

          by Jeremy Erwin ( 2054 )

          And that's why Top500 should use another benchmark. If the beancounters use Top500 to allocate resources, and the supercomputing companies use the beancounter's allocations to determine the future direction of their products, the scientists lose out. It's not so much that Tianhe-1 gamed the benchmark, it that's this gaming could lead to a machine that's not very useful.

        • The research I do is often done on HPC. We've got a little in-house cluster that can do our jobs at about 10% of the efficiency of a HPC, for less than 1% of the price. Why? Our computing requires massive data IO, so we just built our cluster around that. Drives, backplane, all geared to the highest IO we could do. Processors are wimpy, and the cheapest we could go. When I watch jobs, the IO is saturated, the processors are running at about 30-50%, the ram is nearly saturated.

          If we'd just bought HPC time,
        • Are you saying that you work in a place with highly incompetent management? That's hardly top500 benchmarks fault.

          What comes to the real codes you keep repeating is that there is no such thing as a standard for real codes. LINPACK provides one benchmark and is a good tool for that. Benchmarks are excellent for the true HPC where more and more tasks can be done extremely fast with highly specialized machines. If you need general purpose super computer you must not aim for a top spot in LINPACK.

    • Re: (Score:2, Insightful)

      by SnarfQuest ( 469614 )

      I have always wondered why being on the Top500 list of supercomputers that important for those on the list.

      I always choose my supercomputers from the Bottom500 list.

      I will be better served by being told the advantage(s) or edge those who've been on that list have gotten since they got onto the list. Thanks.

      At the price level these things cost, you can probably list your own requirements instead of accepting the vendors.

      If you are purchasing a SuperComputer, you are looking for something to do raw number crunching. You aren't worrying about how well it will run MicroSoft Word, or how many frames/second you'll get out of doom.

    • It's like trying to rank the most "intelligent" people by IQ. OK, you can score them on that test, and you can sort that list of scores, but what does it tell you when there are so many other kinds of intelligence, ad so many other ways to measure it?

    • There is another reason other than running the generic linear/non-linear algebraic apps.

      "If you build it, they will come." is true in this case. When you build a massive machine, you tend to attract minds that have big problems to solve. Looks good on paper when filing up the tree. Makes the institution look good. Makes the country look good. Compute plus minds make a good recipe for great results.

      Now, I'm not saying that those sort of minds absolutely need that machine, rather they have a piece of cod

  • I want the one with the bigger GPUs and the WiFis.
  • Missing the Point (Score:5, Insightful)

    by Lev13than ( 581686 ) on Friday November 19, 2010 @01:30PM (#34283178) Homepage

    As the article alludes, the big problem with ranking supercomputers via Linpack is that it doesn't advance supercomputer design. The net result is a pissing match over scalability, where winning is dependent upon who can cram the most cores into a single room. The real innovatiors should be recognized for their efforts to reduce space, power and cost, or finding new algorithms to crunch the numbers in more efficient or useful ways.

    • by Rob Kaper ( 5960 )

      Why shouldn't advancements in distributed efforts count as supercomputer design? Space, power and cost reduction are all there, cloud computing is not only about scalability but definitely also about efficiency.

    • by TheLink ( 130905 )
      Meh, did the Top500 list actually advance supercomputer design in the first place?

      I thought it has always been a mostly pointless pissing match "where winning is dependent upon who can cram the most cores into a single room" just like you stated.

      Or probably more accurately - "who has the most money to waste/spend on building a supercomputer".
      • Now, hold on. There is a positive impact on the technology. It's just diffuse.

        Score high on Top500. Work that into your marketing. Make better sales. Profit!!

        OK, no technology so far. Bear with me.

        Divert a tiny portion of your Profit!!, after executive compensation and high-priced lobbying and election-buying, after dividends, after management bonuses, after unwise merger and acquisition activity... After all that, divert a small portion of the Profit!! into R&D. The technology advances... a tiny bit. B

    • Normally I would agree with that kind of thing, but super-computers are custom deals. The people who buy them aren't going into Costco some afternoon to pick up a new desktop and choosing the thing with the highest number, they are paying a lot of cash for these things, and they better do some deep analysis to make sure it does what they want. You don't just go up and buy a top 500 computer.

      Linpack is for the rest of us, like me, who don't particularly care about super-computing, but like to look at shiny
    • You are allowed to use hardware-specific features and change the algorithm for this benchmark. That way, any optimization is used and innovation, as you call it, emerges. Besides, scalability *is* the most desired quality for a supercomputer that doesn't aim for space, power and cost... like the ones most likely to be in TOP500. You have Green500 for the other things you mentioned.
    • > The real innovatiors should be recognized for their efforts to reduce space, power and cost

      Trust me, to build a computer for the top of the top500, you have to be pretty good at these. Well, at least space and power. With over 100,000 cores, without an efficient (dense) packaging you'll need a room way too big. And a dense packaging leads to all kind of heat issues, so you have to be power-efficient.

      • by blair1q ( 305137 )

        Cost too. Otherwise each of these would have simply been specified to be 10 times the size it is. But cost and purpose come into play, so the total capability of the system gets limited.

        That said, 100,000 smartphones would cost about $40 million. Which isn't unreasonable. And it would indeed outperform all of these machines on LINPACK tasks. If I were selling smartphones, I'd be putting that in my ad copy today.

        • Maybe they'd cost 40 million bucks retail, but Smartphones cost maybe $30 to make.

        • by 1729 ( 581437 )

          That said, 100,000 smartphones would cost about $40 million. Which isn't unreasonable. And it would indeed outperform all of these machines on LINPACK tasks

          Yeah, right. Look at the number of cores on the current list: 200-300k. (By the end of next year, it will be approaching 2M cores.) You think your 100k ARM-powered, memory limited smartphones could compete? And with what interconnect? USB? Bluetooth? WiFi? Good luck with that.

    • by timeOday ( 582209 ) on Friday November 19, 2010 @02:24PM (#34283732)

      The real innovatiors should be recognized for their efforts to reduce space, power and cost, or finding new algorithms to crunch the numbers in more efficient or useful ways.

      And NHRA should start awarding drag-racing championships on fuel efficiency rather than quarter-mile times.

      Look, the Top500 is about performance, as in speed. There are other metrics for flops/watt or flops/dollar, or whatever. If those were the lists that managed to draw competitors and eyeballs, then nobody would care about Top500 and we wouldn't have to quibble about whether Linpack is a representative benchmark of what it claims to measure: speed.

      • And NHRA should start awarding drag-racing championships on fuel efficiency rather than quarter-mile times.

        If they did, I believe this car [youtube.com] would probably win...
        Hell, it might even win based only on quarter-mile times!

    • big problem with ranking supercomputers via Linpack is that it doesn't advance supercomputer design. The net result is a pissing match over scalability, where winning is dependent upon who can cram the most cores into a single room. The real innovatiors should be recognized for their efforts to reduce space, power and cost, or finding new algorithms to crunch the numbers in more efficient or useful ways

      Don't know about you but the sudden urgency to enter Linpack pissing matches has been suppressed since the

    • by mikael ( 484 )

      Figuring out how to make supercomputers superscalar was one of the research areas in the past. That was solved by figuring out to rack, stack and pack multi-core CPU's on standard boards that fitted into scalable rack units. Then there was the problem of inter-node communication. All sorts of topologies were considered; grid, cube, torus, hyper-torus, hyper-cube, then they figured out having a dynamically configurable topology adapted to the algorithm being run worked best. Once you've got those two sorted

  • by Monkeedude1212 ( 1560403 ) on Friday November 19, 2010 @01:31PM (#34283188) Journal

    int i = 0;
    while(i infinite)
    {
    i++;
    }

    ---

    Whatever computer finishes first is clearly the fastest supercomputer.

    • Re: (Score:3, Informative)

      Right. (Less than symbol didn't show up because I didn't choose plain text! Derr)

      • "Right. (Less than symbol didn't show up because I didn't choose plain text! Derr)"

        Actually, it didn't show up because you didn't preview it.

      • by mcgrew ( 92797 ) *

        You have to use the ampersand to get a <, even using the plain text mode. Do this: &lt; You get this:<

    • Sounds like a job for quantum computing.
    • Re: (Score:2, Funny)

      by atmtarzy ( 1267802 )

      We all know Linux is great... it does infinite loops in 5 seconds.

      - Linus Torvalds about the superiority of Linux on the Amterdam Linux Symposium

    • Any modern compiler will see that this code does nothing and simply remove it. Your benchmark is a no-op :-)

    • I've got something a bit better here:

      while(1) {
              system.exec('yes');
      }

      That way, instead of 1 infinite process doing nothing, you spin up an infinite number of infinite processes doing basically nothing.

      • WTF is system.exec?

        If you mean system(), it'll just launch one and block. If you mean exec*(), they'll launch one replacing the current process.

        • That wasn't meant to be 100% accurate code (I haven't written production C for a while now), just an approximate demonstration of what you could do.

          If I were doing the real thing, I'd probably do a fork and set the child process to exec something nice and useless like 'dd if=/dev/urandom of=/dev/null'.

    • int i = 0;
      while(i infinite)
      {
      i++;
      }

      ---

      Whatever computer finishes first is clearly the fastest supercomputer.

      ::Sigh:: the loop completes in 0 iterations.
      The code is equivalent to:
      while (0) { /* dead code */ }

      So, it would be an accurate test of how quickly you can load and unload a single program from memory.

    • by Bengie ( 1121981 )

      int i = 0;
      while(i infinite)
      {
      i++;
      }

      ---

      Whatever computer finishes first is clearly the fastest supercomputer.

      while(++i)

  • Is there a useful purpose for this list in the first place? It isn't likely to useful to THAT many people...
  • If it can't handle a Starcraft 2, 8 player, full army of all zerglings rush without choking with max settings at a 1080p resolution, it's not a supercomputer.
  • by Yvan256 ( 722131 ) on Friday November 19, 2010 @01:43PM (#34283294) Homepage Journal

    The guide has this to say about supercomputers: "Supercomputers," it says, "are big. Really big. You just won't believe how vastly, hugely, mindbogglingly big they are. I mean, you may think your SGI Challenge DM is big, but that's just peanuts to supercomputers, listen..."

  • Redefine all variables in LINPACK to be higher precision than available from any graphics processor. 128 bit floats, for example. (Requires writing a library to handle the new floats, obviously.)
    • It would hurt both the GPU and the CPU performance. Maybe not in the same way, but still.

      Plus the article complaining about the use of GPUs is stupid. GPUs can be and are used to solve real scientific problems. They are not as easy to efficiently use as the CPUs, but they are almost as versatile.

    • Since when are GPU's not a valid CPU design? In fact, many of the top 500 resemble a GPU much more than your favorite old x86. IBM's Blue Gene is made up of a huge pile of fairly low clocked (
      The part of GPU's that is general purpose is pretty much the same thing - a big pile of vector processors and a fat memory pipe.
      • Excuse me, slashdot ate my comment, but to finish the second sentence:
        IBM's Blue Gene is made up of a huge pile of fairly low clocked (less than 2ghz) dual core powerpc chips optimized for vectorized floating point operations.
    • by afidel ( 530433 )
      Uh, why? If the vector units on GPU's are now good for doing real scientific workloads why would you want to nerf the test? Remember the big NEC earth simulator that was on the top of the list for so long, it was nothing but a bunch of vector processors. If they can get information in and out of the GPU fast enough and have enough interconnect bandwidth with low enough latency then it's useful for doing most supercomputer type workloads.
  • Good to hear (Score:5, Informative)

    by Sycraft-fu ( 314770 ) on Friday November 19, 2010 @01:50PM (#34283350)

    The Top500 has the problem in that many of the systems on there aren't super computers, they are clusters. Now clusters are all well and good. There's lots of shit clusters do well, and if your application is one of them then by all means build and use a cluster. However they aren't supercomputers. What makes supercomputers "super" is their unified memory. A real supercomputer has high speed interconnects that allow direct memory access (non-uniform with respect to time but still) by CPUs to all the memory in the system. This is needed in situation where you have calculations that are highly interdependent, like particle physics simulations.

    So while you might find a $10,000,000 cluster gives you similar performance to a $50,000,000 supercomputer on Linpack, or other benchmark that is very distributed and doesn't rely on a lot of inter-node communication, you would find it falls flat when given certain tasks.

    If we want to have a cluster rating as well that's cool, but a supercomputer benchmark should be better focused on the tasks that make owning an actual supercomputer worth it. They are out there, that's why people continue to buy them.

    • by afidel ( 530433 )
      Interconnect topology definitely does affect Linpack performance, perhaps not to the degree that it affects some other hard cases, but it is definitely a factor and shows up in the ratio of Rpeak to Rmax. Even so a 2D mesh of Infiniband or 10GbE connections is sufficient for all but the most chatty of problems.
    • Re:Good to hear (Score:4, Insightful)

      by timeOday ( 582209 ) on Friday November 19, 2010 @02:36PM (#34283854)
      OK, so you think only algorithms requiring uniform memory access are valid benchmarks. How uniform does it have to be? Real world problems do have structure, they do have locality, and an architecture that fails to exploit that is going to lose out to those that do.

      Sure, your point is taken, otherwise you could say "my benchmarks is IOPS" and "my computer is every computer in the world" and win. But Linpack is not that; you can't score well without a fast interconnect, because what it measures is a set of computations that are actually useful. (Which is why the quip about a beowulf cluster of Android smartphones is stupid... because it couldn't actually be done. Go ahead and try to get on Top500 with a seti@home-type setup.)

  • Even with an hypothetical hyper-fast network, 100.000 android phones won't get you anywhere near the top of the list.

    Heck, even 100 000 Nehalem (core i7) cores won't get you in the top 5.

    So, android phones ? You'll need millions of them.

    • by Kvasio ( 127200 )

      Even with an hypothetical hyper-fast network, 100.000 android phones won't get you anywhere near the top of the list.

      Heck, even 100 000 Nehalem (core i7) cores won't get you in the top 5.

      So, android phones ? You'll need millions of them.

      But does it run Linux? Can You Imagine a Beowulf Cluster of These?

  • ...is that *no* single-figure-of-merit benchmark is going to be worth anything. Sandia's "Graph 500" Johnny-come-lately isn't going to be any better than Linpack that way, and will just skew the results towards a different not-generally-useful architecture. A far better idea has been around for over five years: the HPC Challenge [utk.edu] benchmark. It consists of seven different tests (Linpack is just one) which stress different aspects of system design. Anybody who knows anything about building big systems woul
  • by pushing-robot ( 1037830 ) on Friday November 19, 2010 @01:53PM (#34283384)

    Good news, everyone! Our supercomputer OS only lost because it's buggy!

    • Re: (Score:3, Interesting)

      Good news, everyone! Our supercomputer OS only lost because it's buggy!

      Leela: How is that good news, Professor?

      Professor Farnsworth: I still charge enough per seat to be feared.

  • by icannotthinkofaname ( 1480543 ) on Friday November 19, 2010 @01:54PM (#34283392) Journal

    In other supercomputer news, it turns out the Windows-based cluster that lost out to Linux stumbled because of a bug in Microsoft's software package.

    As it should. That's not news; that's how the game is played. If your software is buggy, and those bugs drag your performance far enough down, you don't deserve a top500 spot.

    If they fix their software, rerun the test, and perform better than Linux, then they will have won that battle (the battle for the top500 spot, not the battle for market share) fair and square.

    • by anss123 ( 985305 )
      In this case it was the benchmark software that was buggy, not the OS. The interesting bit, as noted by the article, was: Why did Windows perform better on small workloads compared to Linux?
      • Re: (Score:2, Informative)

        In this case it was the benchmark software that was buggy, not the OS.

        Yeah that's right, the LINPACK benchmark software that Microsoft strangely got to rewrite themselves. Yep that's apparently where the bug was.

        I wonder why MS was given the task of rewriting the benchmark in the first place. I guess it will always be a mystery... oh hold on, no wait... "It should be noted that Microsoft has helped fund the Tokyo Institute of Technology's supercomputing programs." Guess it helps to read the sentences they stick near the end of unrelated paragraphs at the end of the articles.

        • by jsac ( 71558 )
          Did you miss the part of the artlcle where the TITECH team working on the Linux Top500 run on Tsubame also had to rewrite their HPL stack?
        • I wonder why MS was given the task of rewriting the benchmark in the first place.

          I don't know anything about it, but one of the earlier posters remarked that LINPACK is specifically allowed to be tweaked for hardware and OS specific optimizations to squeeze every last bit out of it.

  • Speed is one thing, but how about normalizing the list by how well its owners are utilizing those transistors?
  • The single largest expense, over the lifetime of a supercomputer, is power consumption.

  • >But the Benchmark is in FLOPs which uses FLUs.(Like ALUs)
    So if they have problems then the only ones to blame are the Designers of the computer.
    A FLOP, is a FLOP, is a FLOP.

    The possible problems are:
    A. The aren't using the Math Libraries correctly.
    B. They aren't using the CPU's or GPU's FLU correctly.
    C. They configured the system bad. (I.e. Networking, etc)
  • > one high-performance-computing vendor executive joked about stringing together 100,000 Android smartphones to get...

    Now that's not entirely fair. I just looked at an Android smartphone at Best Buy, and the sales rep assured me that I should be buying the bigger, more expensive one, rather than the one I could fit in my pocket, because it was faster. It even has a snapdragon processor! (whatever that is) Surely it can't be that far away from a true supercomputer.

  • the reason they use GPU's is to run the simulation tasks much more efficient. You have a good compiler that can split-up the work load - I suspect something like an extended FORTRAN

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