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Petaflops? DARPA Seeks Quintillion-Flop Computers

CmdrTaco posted more than 3 years ago | from the that's-a-lotta-flops dept.

Supercomputing 185

coondoggie writes "Not known for taking the demure route, researchers at DARPA this week announced a program aimed at building computers that exceed current peta-scale computers to achieve the mind-altering speed of one quintillion (1,000,000,000,000,000,000) calculations per second. Dubbed extreme scale computing, such machines are needed, DARPA says, to 'meet the relentlessly increasing demands for greater performance, higher energy efficiency, ease of programmability, system dependability, and security.'"

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185 comments

Make sense, dammit (4, Informative)

Lord Grey (463613) | more than 3 years ago | (#32667618)

From TFA, written by Michael Cooney and propagated by the summary:

Dubbed extreme scale computing, such machines are needed DARPA says to "meet the relentlessly increasing demands for greater performance, higher energy efficiency, ease of programmability, system dependability and security."

It looks like these "extreme scale computing" systems are needed before things like "ease of programmability" can be acheived. I call bullshit.

The actual notice from DARPA is named Omnipresent High Performance Computing (OHPC) [fbo.gov] . From the first paragraph of that page:

... To meet the relentlessly increasing demands for greater performance, higher energy efficiency, ease of programmability, system dependability, and security, revolutionary new research, development, and design will be essential to enable new generations of advanced DoD computing system capabilities and new classes of computer applications. Current evolutionary approaches to progress in computer designs are inadequate. ...

That makes a lot more sense.

Now, will someone please go and smack Michael Cooney up the back of head for writing like that?

Re:Make sense, dammit (5, Informative)

Animats (122034) | more than 3 years ago | (#32667844)

Right. If you actually read the announcement, it's not that they want yet more boondoggle supercomputing centers. What they want is more crunch power in small boxes. Read the actual announcement [fbo.gov] (PDF). See page 17. What they want is 1 petaflop (peak) in one rack, including cooling gear. The rack gets to draw up to 57 kilowatts (!).

Re:Make sense, dammit (2, Informative)

Anonymous Coward | more than 3 years ago | (#32668832)

Quick napkin math:

Rack has 42U

SuperMicro servers (TwinX) have 2 "blades" per 1U rail slot.

Each blade has 2 6-core Intel Nehalem CPUs generating approximately 225 GFLOPS each, or 450 per U.

18.9 TFLOPS per rack and consuming a peak of over 78,000 BTU and 600 amps and 72KW (breaking the budget).

Yep, there's a long way to go. Guessing some sort of customizable GPU massively parallel system. It'll be a bitch to develop for, but probably what's required to reach these numbers.

Re:Make sense, dammit (1)

Yvanhoe (564877) | more than 3 years ago | (#32668572)

Translation : WPA2 is a bit harder to crack than expected but don't worry, we are giving our NSA kids all the tools they need !

how sweet and innocent of them! (5, Insightful)

zero.kalvin (1231372) | more than 3 years ago | (#32667644)

Call me tinfoil hat wearer, but me thinks they want a faster way of cracking encryption...

Re:how sweet and innocent of them! (4, Interesting)

Entropius (188861) | more than 3 years ago | (#32667676)

Good luck. I can encrypt something in polynomial time (quadratic, isn't it?) that it takes you exponential time to encrypt.

Re:how sweet and innocent of them! (2, Insightful)

John Hasler (414242) | more than 3 years ago | (#32667934)

But you'll have to fully deploy your longer keys long enough before they deploy their exaflop cracker that none of the inadequately-protected messages already in their possession are useful to them.

I suspect that simulations are more interesting to them, though. Think what they'd save on testing if they could fully simulate hypersonic flight and scramjet engines (not that I don't think they'll use this for cracking).

Re:how sweet and innocent of them! (1)

Cyberax (705495) | more than 3 years ago | (#32668194)

4096-bit RSA encryption and 256-bit symmetrical encryption are way outside of capabilities of any imaginable classical computer.

Now, the problem might be in a insecure passphrase used to generate AES keys...

Re:how sweet and innocent of them! (1)

Surt (22457) | more than 3 years ago | (#32668612)

Not outside the capabilities of a classical computer, outside the capabilities of known decryption algorithms on conventional computers. The fact that the NSA is still serving a purpose in spite of 'completely secure' key sizes should suggest a fairly obvious conclusion.

Re:how sweet and innocent of them! (1)

compro01 (777531) | more than 3 years ago | (#32668720)

The fact that the NSA is still serving a purpose in spite of 'completely secure' key sizes should suggest a fairly obvious conclusion./quote?

That people are too cheap/lazy/apathetic to bother encrypting stuff?

Re:how sweet and innocent of them! (0)

Anonymous Coward | more than 3 years ago | (#32668530)

Good luck. I can encrypt something in polynomial time (quadratic, isn't it?) that it takes you exponential time to encrypt.

Encrypt, decrypt, what's the difference, when you're talking out your ass?

How the fuck is this "informative"? Who does it "inform"? What does it "inform" them of? That the poster doesn't know the difference between encryption and decryption?

Re:how sweet and innocent of them! (2, Interesting)

SirGarlon (845873) | more than 3 years ago | (#32667680)

Actually, the military being able to crack encryption is in some sense a Good Thing. It enables them to conduct espionage and counter-espionage against adversaries such as North Korea and Al-Quaeda. Yeah that's kind of a Cold War mentality, but what is "cyber warfare" if not Cold War II?

Re:how sweet and innocent of them! (1, Insightful)

Anonymous Coward | more than 3 years ago | (#32667768)

It enables them to conduct espionage and counter-espionage against adversaries such as North Korea and Al-Quaeda.

...AND protect constitutional rights! More power to you!

Re:how sweet and innocent of them! (1)

stanlyb (1839382) | more than 3 years ago | (#32667772)

Since when the espionage is a GOOD thing!!!!! And please, don't tell me: Bond, James Bond.

Re:how sweet and innocent of them! (4, Insightful)

SirGarlon (845873) | more than 3 years ago | (#32668084)

Since when the espionage is a GOOD thing!!!!!

Since September 11, 2001.

Or you could go back further, to July 26, 1939 [wikipedia.org] . But the real answer is, espionage has been a good thing ever since there have been enemies.

I for one am all in favor of having fewer enemies. But for the ones that can't be ignored or reconciled, espionage is a Good Thing.

Re:how sweet and innocent of them! (1)

phantomfive (622387) | more than 3 years ago | (#32668130)

Uh, don't know if you consider it a good thing, but the computer science great Alan Turing helped with espionage that made a huge difference in WW2. Thanks to his (and others') work, the allies knew the position of almost all the german troops before D-day. That is important information. It was significant in a number of WW2 battles, check it out [wikipedia.org] .

Maybe you don't think that was a good thing, but you are definitely in a minority in your opinion. There have been lots of effective uses of espionage, including in the current Iraq/Afghanistan war.

Re:how sweet and innocent of them! (1)

stanlyb (1839382) | more than 3 years ago | (#32668772)

Let me say it this way: Since when the regular guy is considered a terrorist, lol.

Re:how sweet and innocent of them! (0)

Anonymous Coward | more than 3 years ago | (#32668778)

One could argue a distinction between wartime espionage and peacetime espionage. A lot of what peacetime espionage combats if you look through the timeline are the undesirable side effects of doing peacetime espionage in the first place.

Clearly it has uses, uses that can benefit various entities. The overarching question though is does espionage cause more harm to the larger society than the benefits it provides. I believe a pretty strong argument can be made that we'd all be better off dropping the whole enterprise and instead narrowly focusing on the smaller issues that can arise when you don't practice spycraft as a day in day out operation.

I've found that in most cases that supporters point to as a big benefit of running a large spy business are situations we never should have gotten ourselves into in the first place. Yes a garrote might be useful if you find yourself at a hated ex's house who has a restraining order against you and is trying to take away your custody rights, but perhaps you could have just not been a dick to her in the first place and treated her with respect?

Re:how sweet and innocent of them! (1)

AthleteMusicianNerd (1633805) | more than 3 years ago | (#32668328)

As long as they don't start using the technologies on the citizens of the US. Do you trust them?

Re:how sweet and innocent of them! (1)

SirGarlon (845873) | more than 3 years ago | (#32668476)

As long as they don't start using the technologies on the citizens of the US. Do you trust them?

No. But if you take away their technology to spy on citizens, you also take away their ability to spy on enemies. Technology is like that. People can use it for Good Things or Bad Things. We learned that in the 20th century.

Re:how sweet and innocent of them! (1)

stanlyb (1839382) | more than 3 years ago | (#32669054)

Please, tell me which amendment, or at least stature is using your words "for good and bad use of technology"???

Re:how sweet and innocent of them! (1)

stanlyb (1839382) | more than 3 years ago | (#32668952)

Exactly my point. Is there anyone naive enough to trust them? Do you know that in France it is forbidden to encrypt your mails? Mails, not e-mail.....

Re:how sweet and innocent of them! (2, Informative)

$RANDOMLUSER (804576) | more than 3 years ago | (#32669004)

If I'm North Korea or Al-Qaeda or "Red" China, or any one of a million other defined-as "bad guys", I'm not using RSA or some such, I'm using one-time-pads [wikipedia.org] or steganography [wikipedia.org] on any one of a billion different chat boards, probably one where I can post JPEGs. Places where the message location and encryption itself is all the sender signature it needs. It's the bankers and the private citizens (and possibly some foreign diplomatic services) who are using RSA and public-key type ciphers that (might maybe potentially could be) cracked by lots and lots of computing power.

Meanwhile, this is perfect paranoia-food for the "ECHELON is reading my e-mails and SMS!" types. Thing is, they're probably right.

Re:how sweet and innocent of them! (1)

Monkeedude1212 (1560403) | more than 3 years ago | (#32667764)

I think they want a faster way to preform a DOS attack. They plan to send so many pulses down the line at once that the ethernet cable vibrates so much it gets unplugged by your server.

Don't believe me? Send a letter to mythbusters.

Re:how sweet and innocent of them! (3, Funny)

maxwell demon (590494) | more than 3 years ago | (#32667828)

Sorry, but DOS attacks are utterly outdated. Today you use Windows for your attacks.

SCNR

Re:how sweet and innocent of them! (0, Troll)

BobMcD (601576) | more than 3 years ago | (#32667974)

Amen. They could have saved a lot of keystrokes...

Dubbed extreme scale computing, such machines are needed, DARPA says, to crack into the gmail accounts of millions of Americans and discern how to keep the wool firmly over their eyes.

Re:how sweet and innocent of them! (1)

mea37 (1201159) | more than 3 years ago | (#32668100)

You're conflating government agencies. If you want to worry that the government is reading your email, you want to talk about the NSA. DARPA is more likely to be building toys for the military.

Ever wonder how they test nuclear weapon designs these days?

Exaflops (5, Informative)

maxwell demon (590494) | more than 3 years ago | (#32667654)

Quintillion is not an SI prefix. The next step after Peta is Exa.

Re:Exaflops (3, Informative)

daveime (1253762) | more than 3 years ago | (#32667724)

Nope, Quintillion is a quantity, whereas Petaflops, Exaflops etc are rates of calculations per second. Please don't mix your units in your haste to appear smart.

Re:Exaflops (2, Funny)

Pojut (1027544) | more than 3 years ago | (#32667846)

Just like people complaining how in Star Wars, Han Solo said he made the Kessel Run in less than 12 parsecs...yes, we know that parsecs are a measure of distance, Solo was talking about being able to complete the race using a shorter route than the standard 18 parsecs, which is why a measure of distance makes sense.

Source [wikia.com] .

Disclaimer: some people may shout "retcon" at this explanation, but at this point singling out each instance retconning in the Star Wars universe is a wasted effort.

Re:Exaflops (1)

blair1q (305137) | more than 3 years ago | (#32668524)

1. Hyperspace: distance and time are merely four directions in an orthogonal 4-space. So saying you made it in 12 parsecs when using a hyperdrive is completely correct. It's x^2+y^2+z^2+t^2 = 12^2.

2. I thought everyone knew this.

3. Han shot first, goddammit.

Re:Exaflops (1)

Garble Snarky (715674) | more than 3 years ago | (#32668016)

"quintillion-flop" is also a rate of calculations per second, which is equivalent to the more concise "exaflop". What's the problem?

Re:Exaflops (0)

Anonymous Coward | more than 3 years ago | (#32668614)

One quintillion calculations per second is not a quintillion-flop, its an exaflop. Not very difficult.

Re:Exaflops (0)

Anonymous Coward | more than 3 years ago | (#32668820)

Describing a quantity of Floating point operations is meaningless. If you don't specify a rate, and use the term "FLOP", then you're talking about that many operations.

By this logic, my old Pentium III is a Quintillion-FLOP computer - it can complete one quintillion floating point operations, albeit very slowly.

Also, "one quintillion FLOPS" is like saying three billion hertz, correct but quite unusual.

Re:Exaflops (0)

Anonymous Coward | more than 3 years ago | (#32667746)

Warning: Common sense ahead [wikipedia.org] .

Re:Exaflops (2, Funny)

Chowderbags (847952) | more than 3 years ago | (#32667824)

FLOPS is not an SI unit.

Re:Exaflops (2, Informative)

DragonWriter (970822) | more than 3 years ago | (#32668602)

FLOPS is not an SI unit.

True, that: FLOPS communicates a combination of the SI unit (1/s = Hz) with the identity of the thing being measured (floating point operations). It's like if you had KOM as an abbreviation for kilograms of milk.

Re:Exaflops (1)

Pharmboy (216950) | more than 3 years ago | (#32668026)

Regardless, its a metric assload of processing power. The only obvious reason I can see for this type of computing power is to render encryption by the average computers useless.

Peta-flops (2, Funny)

Anonymous Coward | more than 3 years ago | (#32667664)

I'm glad DARPA is finally making a move to make their computing more animal friendly.

Translation (4, Funny)

Rik Sweeney (471717) | more than 3 years ago | (#32667668)

I want to run Crysis 2 in software rendering mode

Re:Translation (1)

gsgriffin (1195771) | more than 3 years ago | (#32667984)

I scrolled quickly down the page wondering how long it would take to get the gaming statement. Well!! Here it is!!

Next, queue porn comment...

Re:Translation (0)

Anonymous Coward | more than 3 years ago | (#32668774)

s/queue/cue/g

I, for one (0)

Anonymous Coward | more than 3 years ago | (#32667672)

I, for one, welcome our new Skynet overlords. :)

Missed one... (0)

Anonymous Coward | more than 3 years ago | (#32667700)

Domestic signals processing. All of them.

Computing for the next generation (1)

ch-chuck (9622) | more than 3 years ago | (#32667726)

X-tream scale, mind altering computing...

That was we can simulate nuking out enemies faster than they can simulate nuking us.

Or they could come up with climate models that are actually almost somewhat predictive.

Re:Computing for the next generation (2, Informative)

TheKidWho (705796) | more than 3 years ago | (#32668004)

You've been simulated to die in our ongoing war with Eastasia, please report to the gassing chambers promptly to prevent the simulation from experiencing temporal improbabilities.

Re:Computing for the next generation (1)

maxwell demon (590494) | more than 3 years ago | (#32668976)

You've been simulated to die in our ongoing war with Eastasia, please report to the gassing chambers promptly to prevent the simulation from experiencing temporal improbabilities.

I guess whoever moderated that comment informative is now searching the gassing chamber to report himself ... :-)

Two words: (0)

Anonymous Coward | more than 3 years ago | (#32667760)

Holodeck porn.

I Love DARPA (5, Insightful)

sonicmerlin (1505111) | more than 3 years ago | (#32667782)

They come up with ideas that only ultra-geeks and science fiction nerds could come up with, and then they get billions in funding for it! It's like paradise. The fact that they're actually successful at advancing human technology is just icing on the cake.

Re:I Love DARPA (4, Informative)

MozeeToby (1163751) | more than 3 years ago | (#32668116)

Most people don't realize it but DARPA can best be described as a few dozen scientists and engineers with large checkbooks and a big travel budget. They go around the country and around the world looking for technologies that are beyond what we can do today but might be possible with the right funding in the right places. Most importantly, they're aware that a large percentage of the projects that they fund will end in failure (or rather, will not meet all their goals), but the benefits of the ones that don't outweigh the costs.

Re:I Love DARPA (2, Interesting)

Courageous (228506) | more than 3 years ago | (#32668650)

It's even more interesting than that. If DARPA begins succeeding a lot, DARPA seniors end up having to explain to congress (yes, directly to congress) why it is they aren't forward-leaning enough. I.e., DARPA programs are expected to fail often, and congress uses this failure rate as pro forma information about how "researchy" DARPA is.

Joe.

What's the need? (2, Interesting)

Just Some Guy (3352) | more than 3 years ago | (#32667810)

First, I'm entirely ignorant of supercomputing. I don't know the first thing about it. I'm asking this out of sheer lack of knowledge in the field:

What do you need a computer that fast for?

I mean, specifically, what can you do on something that fast that you couldn't do on one 1,000 (or 1,000,000) times slower? What kind of tasks need that much processing power? For example, you normally hear about them being used for things like weather simulation. Well, what is it about weather simulation that requires so much work?

The whole idea is fascinating to me, but without ever having even been near the field, I can't imagine what a dataset or algorithm would look like that would take so much power to chew through.

Re:What's the need? (5, Informative)

Yoozer (1055188) | more than 3 years ago | (#32668072)

What do you need a computer that fast for?

Simulating exploding hydrogen bombs, weather simulation, brute-force cracking, etc. Basically any distributed project you can think of (see BOINC [berkeley.edu] ) can also be done with a supercomputer.

Well, what is it about weather simulation that requires so much work?

It's a scientific model with a boatload of variables and dependencies. Ask these guys [earthsystemmodeling.org] .

Re:What's the need? (4, Informative)

Hijacked Public (999535) | more than 3 years ago | (#32668086)

Well, what is it about weather simulation that requires so much work?

The enormous number of variables, mostly. Weather, nuclear bombs, ocean currents, cryptography, even things as seemingly simple as modeling air flow around an object. If you are looking to develop a model of a process that involves a few thousand variables and you need to know the interaction of those variables several levels deep....you need to make a lot of calculations.

It hasn't been all that long that computers have had the computational power to dominate humans in games as 'simple' as chess.

Re:What's the need? (3, Insightful)

Chowderbags (847952) | more than 3 years ago | (#32668102)

I mean, specifically, what can you do on something that fast that you couldn't do on one 1,000 (or 1,000,000) times slower? What kind of tasks need that much processing power? For example, you normally hear about them being used for things like weather simulation. Well, what is it about weather simulation that requires so much work?

Theoretically there's nothing you can't do on a supercomputer that you couldn't do with an ordinary desktop computer (except possibly for memory constraints), but for that matter you could also do everything by hand. The thing is, when your problem space is very large (i.e. calculating all interactions between X number of objects, where X is some huge number, or solving something like the Traveling Salesman Problem), you are limited in your options of what you can do to get results faster. If you're lucky, you can find some speedup of your problem (I.E. going to a better level of O-complexity [O(2^N)->O(n^2) would be a huge speedup, but doesn't happen often]), or tossing more resources at it. Yes, it'll still be slow, but if it takes you a year to do on a supercomputer, that's quite a bit better than spending 1000 years waiting on a regular computer.

Re:What's the need? (1)

TheKidWho (705796) | more than 3 years ago | (#32668146)

Well, what is it about weather simulation that requires so much work?

Might have something to do with the billions upon billions of billions of billions of atoms that need to be simulated.

The more processing power one has, the finer the simulation parameters.

Re:What's the need? (2, Informative)

John Hasler (414242) | more than 3 years ago | (#32668172)

I mean, specifically, what can you do on something that fast that you couldn't do on one 1,000 (or 1,000,000) times slower? What kind of tasks need that much processing power?

Detailed, 3-D simulation of things like nuclear explosions and scramjet engines.

For example, you normally hear about them being used for things like > weather simulation. Well, what is it about weather simulation that requires > so much work?

Accuracy. Weather Prediction [wikipedia.org]

Re:What's the need? (3, Informative)

maxwell demon (590494) | more than 3 years ago | (#32668180)

Imagine a simulation in 3D space. You model the space by a cube of 100x100x100 grid points. That's one million data points. Now say you have to do some calculation on them which scales quadratic in the number of data points. Say you manage to finish the calculation in one hour on some computer.

OK, but now you notice that those 100 data points in each direction are to inaccurate. You need 1000 points to be reasonably accurate. So now your data set is not one million, but one billion data points. And your O(N^2) algorithm makes sure that this factor 1000 in the number of grid points ends up as a factor one million in your computing time. So now the calculation would, on the same computer, need one million hours, or about 114 years. You almost certainly don't want to wait 114 years to get your results.

Re:What's the need? (1)

Just Some Guy (3352) | more than 3 years ago | (#32668318)

Thanks! That's what I was wondering about. So is that the problem they're trying to solve: current models are too coarse and scientists think they can get more accurate results by increasing the points/partitions/whatever?

Re:What's the need? (1)

maxwell demon (590494) | more than 3 years ago | (#32668632)

That's indeed the problem in many cases, especially for climate simulations, where the accuracy only grows logarithmically with the number of data points.

There are other reasons why you might need more data points, too, like you just want to calculate a larger system. For example, if you are not interested in simple molecules like water, but complicated ones like proteins.

Re:What's the need? (5, Informative)

Chris Burke (6130) | more than 3 years ago | (#32668234)

There are broad classes of algorithms where you can make good use of essentially arbitrary amounts of computing power to get better answers. When doing physical simulations of something like airflow over a jet wing, or the movement of a weather system, or the explosion of a hydrogen bomb, you'll break everything up into tiny units that you treat as monolithic elements whose behavior can be treated relatively simply, and calculate what happens to them over some tiny timescale, call the result the new state of the universe, and repeat. This is called "finite element analysis".

Because you're calculating everything in discreet steps, though, errors creep in and accumulate. The more processing power you have, the more elements you can use and the smaller time scales you can calculate over and get a more accurate answer in the same amount of time. The reason it's unacceptable to do the same calculation but have it go 1,000 or 1,000,000 times slower is that these simulations might already take hours, days, weeks, or even longer. Even the longest DoD contract needs an answer to the behavior of a proposed jet fighter wing in less than 1,000,000 days. :)

Scientific computing is an area where there will always be a use for more processing power.

There are other areas where it can be important, when you have real time constraints and can't just reduce your accuracy to make it work. I recall a story from advanced algorithms class where a bank was handling so many transactions per day that the time it took to process them all was more than 24 hours. Obviously this was a problem. The solution in that case was to modify the algorithm, but that's not always possible, and you need more computing. This is a little different in that you need the extra power to allow growth, as opposed to science where you could hand them an exaflop computer today and they'd be able to use it to its fullest.

Re:What's the need? (3, Insightful)

koxkoxkox (879667) | more than 3 years ago | (#32668236)

If you take weather simulation :

At a given point, you have a bunch of physical equations taking a set of parameters at time t and giving you these same parameters at time t+1. Of course, the smaller the time step, the better the result.

To have the best possible result, you should consider the whole globe at once (think phenomenon like thermohaline circulation for example). However, you should also consider the finest grid possible, to take into account the heterogeneity of the geography, the local variations due to rivers, etc. It is also important to consider a three-dimensional model if you want to transcribe the atmospheric circulation, the evaporation, etc.

I forgot the exact numbers, but Wikipedia gives an example of a current global climate models using a grid of 500,000 points (see http://en.wikipedia.org/wiki/Global_climate_model [wikipedia.org] ), which is a pretty coarse resolution, working with tiles of tens of thousands kilometer square.

With the current computing capabilities, we can not go much farther for a global model. This is already an impressive improvement compared the first models, which were two dimensional and used very simplified equations, overlooking a large number of important physical mechanism.

At the same time, we have satellite data several orders of magnitude more precise. Data from the satellite ASTER were computed to provide a complete altitude mapping of the globe with a theoretical resolution of 90 m. The vegetation cover can be obtained at a resolution of 8m using commercial satellite like FORMOSAT-2. Even the soil moisture can be measured at a resolution of around 50 km thanks to the new satellite SMOS.

These sets of data are already used at the local level, for example to model the transfer between the soil and the atmosphere, taking into account the vegetation (SVAT modelling). It makes no doubt that a global climate model using a more precise grid and these data would significantly improve its prediction.

Re:What's the need? (4, Informative)

chichilalescu (1647065) | more than 3 years ago | (#32668336)

In fluid dynamics simulations (which include weather stuff), there are huge computational problems. I work in the field, so bear with me a little.

The best model we have so far for fluids is to use balance equations (look up the Navier Stokes equations). This means that in order to describe the evolution of a fluid in a given domain, we need to split the domain into small cells, and then integrate numerically the balance equations. To put it simply, you have to integrate numerically a system of ordinary differential equations with many many variables (degrees of freedom).
For a simple but "correct" Navier Stokes simulation, the number of degrees of freedom is proportional to Re^(9/4), where Re is the Reynolds number (the memory requirements are proportional to the number of degrees of freedom). This Reynolds number, for typical systems (like the atmosphere) is of the order of at least 10^4-10^6 (you can look up typical values on wikipedia if you're interested). Furthermore, the number of timesteps needed for a "correct" simulation is proportional to Re^(3/4).

But these are not the most complicated simulations that are to be run on such machines. Research for issues like controled nuclear fusion needs to address much more demanding problems.

Numerical simulations of physical systems are inherently hard, because they scale polynomially with their complexity. However, they are generally cheaper than actual experiments, and you have access to more data.

Re:What's the need? (0)

Anonymous Coward | more than 3 years ago | (#32668390)

Weather simulations are sensitive to infinite digits of precision in their "input". Imagine a grid covering the whole earth. If you can have a grid of 100km x 100km "squares" you have a shitload of data. But your simulation would be more MUCH more precise if you could have a 10km x 10km grid - way way way bigger. Also, you can start a number of simulation with more or less different "input" data - discarding diverging ones and starting new ones with data from sensors. Take earth area, divide by area of your "square", multiply by a few (sizeof double). Do it a number of times. It's big.

I believe cryptology people always have need for more power. Ft Meade (NSA) maxs out their regional electrical grid - or, at least, used to.

Weapons (nuclear) simulations is other field that can always consume more processing power - more precision in simulations, more or less like the weather simulations. You always see DoE involved in HPC.

Datamining even bigger datasets. Tapping everyone in the US and analyzing it takes a lot of computing power ;)

Grossly (very grossly), that's the idea. For sure there's other options I didn't think of.

Re:What's the need? (1)

Surt (22457) | more than 3 years ago | (#32668422)

Imagine you are simulating weather with an accuracy narrowed down to 1000 cubic meters. That's a cube 10 meters on a side, consider it roughly the size of a house. Not very accurate, right? Because there is a lot of detail going on within those 1000 cubic meters that your simulation is ignoring.

But: it's also a vast quantity of data to consider, even at that level of inaccuracy. Just to simulate the weather over the united states you'd have about 20,740,933,333 cells to compute. 20 Billion cells to compute. And who knows how many cycles to compute a days worth of weather per cell? A few billion is probably a low-ball estimate for that. So multiply a few billion by a few billion and pretty soon you're getting into serious numbers.

Re:What's the need? (1)

Just Some Guy (3352) | more than 3 years ago | (#32668688)

Big thanks to everyone who replied! Those are the kinds of answers I was looking for. I have a friend who farms and he has some enormous machines in his fields. I felt the same way about supercomputers as I did about his farming equipment: "Good grief! That must be useful for something or he wouldn't have bought it, but I can't imagine what I'd ever use such a thing for."

Special thanks to everyone who didn't interpret that as an attack on supercomputing or make "640KB ought to be enough for everybody" jokes. I'm ignorant, not dumb. :-)

Re:What's the need? Deep Thought! (1)

redanzl (455100) | more than 3 years ago | (#32668818)

To build an even more powerful computer that will answer the ultimate question of life, the universe, and everything!

Old news (2, Informative)

jdb2 (800046) | more than 3 years ago | (#32667814)

The DOE as well as Oak Ridge, Los Alamos and Sandia National Laboratories already have programs in place to develop an "exascale" system by 2018. ( the date at which Moore's law predicts the possibility of such systems )
The top companies competing for the government funds are, not surprisingly, IBM and Cray.

See these two older /. stories here [slashdot.org] and here [slashdot.org] .

jdb2

The end of the world? (1)

sea4ever (1628181) | more than 3 years ago | (#32667856)

According to the article: "Specifically the outfit is looking for:
*skipped the first 4*
Self aware system software, including operating system, runtime system, I/O system, system management/administration, resource management and means of exposing resources, and external environments."

Uh-huh. This is it! Is it no coincidence that it's called Omnipresence high performance computing?

What's all this I hear about (0)

Anonymous Coward | more than 3 years ago | (#32667908)

pedoflops? How many priests equals one pedoflop?

They need to talk to Apple (0)

Anonymous Coward | more than 3 years ago | (#32668028)

Apple is the ONLY company that can bring the future of computing into reality.

Think different. Think better. Think Apple!

10^9 is not a billion (1)

Kitsune Inari (1801214) | more than 3 years ago | (#32668202)

[...] to achieve the mind-altering speed of one quintillion (1,000,000,000,000,000,000) calculations per second.

Say what you want, but here in the continent I live a million billions is still a trillion, not a quintillion.

Re:10^9 is not a billion (1)

Chris Burke (6130) | more than 3 years ago | (#32668342)

Yeah, different places use different standards.

What I've always wondered is -- what do you call one thousand billions? What do you call two hundred thousand billions? It just seems awkward to have to string so many sizes together, but that's obviously from my perspective of having grown up doing it our way.

Re:10^9 is not a billion (1)

91degrees (207121) | more than 3 years ago | (#32668838)

There are the numbers milliard and billiard for 1000 million and 1000 billion respectively, although I've typically heard the long winded version when it's used. In practice it doesn't matter that much. Values larger than a million aren't used that much except in finance. Science uses standard form and engineering uses SI units because they're less ambiguous.

Prefix Change (1)

pgn674 (995941) | more than 3 years ago | (#32668442)

That's a little odd, changing from SI prefix (metric), which uses mostly Greek words (Petaflops), to short scale, which uses Latin (Quintillion-Flop).

Salvage sale? (1)

gravis777 (123605) | more than 3 years ago | (#32668444)

Since their current petaflop systems are clearly not enough for them, can I pick up a few for $5 a piece at their next salvage sale?

Re:Salvage sale? (1)

Actually, I do RTFA (1058596) | more than 3 years ago | (#32668534)

Since their current petaflop systems are clearly not enough for them, can I pick up a few for $5 a piece at their next salvage sale?

Sure, just know that anything that ever could have held data ( Hard Drives, RAM, Registers on CPUs, etc. ) will be destroyed first.

America is bankrupt (-1, Troll)

Anonymous Coward | more than 3 years ago | (#32668668)

and yet we are still pissing away taxpayer dollars on evil techonology that will give the military more power over common man.

I hope somebody blows up their fagot ass computer.

yeah, right. (2, Funny)

Major Downtime (1840554) | more than 3 years ago | (#32668672)

Pfff, old news. It will produce 42 as final output, and then we'll have it build another machine capable of performing one peta-quazillion calculations per second.

FLOPS, not FLOP (3, Informative)

91degrees (207121) | more than 3 years ago | (#32668730)

You should realise that the "S" stands for seconds. Okay - it doesn't matter that much, but this is meant to be a technical site. The editors should really get this stuff right.
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