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First Petaflop Supercomputer To Shut Down
An anonymous reader writes "In 2008 Roadrunner was the world's fastest supercomputer. Now that the first system to break the petaflop barrier has lost a step on today's leaders it will be shut down and dismantled. In its five years of operation, the Roadrunner was the 'workhorse' behind the National Nuclear Security Administration's Advanced Simulation and Computing program, providing key computer simulations for the Stockpile Stewardship Program."
RR must've spent too much time pecking on that Acme birdseed.
it's be interesting to see if this thing goes for scrap value, or if someone else'll pick it up for service elsewhere...
Operation Guillotine is in effect.
"Sound barrier" was and remains OK because there is a physical difference between flying slower than and faster than the speed of sound. But the word "barrier" is now (over)used to make things sound more dramatic. Raising a number from below to above some arbitrary (usually number base-dependent) threshold does not imply crossing a barrier, unless by barrier is meant "barrier to entry of another over-hyped tech piece".
I think that thing could host a kick-ass DOOM session!
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Rotate the pod, please, HAL....
At today's prices, I'd have it farming Bitcoins.
* Carthago Delenda Est *
I guess it's not new and shiny anymore, so we can just throw it away.
I did want to read the actual article, but the only link is to a 2008 article.
Fail or what?
http://news.sky.com/story/1071902/supercomputer-pioneer-roadrunner-to-shut-down
That is the article. And i see why they are getting rid of it, not as power efficient as new computers.
Be seeing you...
Also, they should use a proper car analogy and use "Milestone".
I've worked for the DOE for quite a few years now writing software for these supercomputers... and I can guarantee you that we use the hell out of them. There is usually quite a wait to just run a job on them.
They are used for national security, energy, environment, biology and a lot more.
If you want to see some of what we do with them see this video (it's me talking):
http://www.youtube.com/watch?v=V-2VfET8SNw
I don't get it are you looking for a Funny mod? You linked to a 2D heat transfer simulation done by Matlab. Did you even watch the video?
The second simulation (of a full nuclear fuel rod in 3D) was nearly 300 million degrees of freedom and the output alone was nearly 400GB to postprocess. It involves around 15 fully coupled, nonlinear PDEs all being solved simultaneously and fully implicitly (to model multiple years of a complex process you have to be able to take big timesteps) on ~12,000 processors.
Matlab isn't even close.
Are you somehow under the impression that these supercomputers are used to count nukes and keep track of their addresses?
Nuclear weapons have things like plutonium and uranium in them. The essential part of those is that they're radioactive. That means they decay. So yes, they do change over time. Since the US has agreed not to go firing the things off to see if they still work, the supercomputers are used to simulate the decay process and firing to see if they still work, what the yield is, and how long they're likely to keep working.
It's kind of embarrassing when the president says "turn them into a radioactive parking lot!" after North Korea nukes San Francisco, and the retaliatory strike is a bunch of duds.
The Coyote finally won
Yeah, that too, is possible !
Muchas Gracias, Señor Edward Snowden !
The problem is energy efficiency. In the past 5 years since it was first built, supercomputers have become far more energy-efficient. Roadrunner falls at 444 MFLOPS per Watt, while the current fastest supercomputer (and also a DOE project), Titan, is 2,143 MFLOPS per Watt. Roadrunner uses 2345 kW, and supporting equipment (cooling, backup power adds (on average) 80% more. Assume they get relatively cheap electricity (The Internets tell me the average price charged to industrial customers is 7/kWh), and that means that their electric bill is at least $295.50 PER HOUR. A computer with the same performance but Titan's efficiency would cost $61 per hour. That's the difference between your electric bill being $2.6 million per year and $500,000.
Assuming Titan's cost also scales ($60 million for 17 Petaflops -> ~$3.5 million for 1 Petaflop), then the payback for scrapping it and building a new computer is under 2 years. So yes, it IS saving money to scrap this one. They're not even replacing it with a new one (yet, anyway) - they're using one that was built in 2010.
And also, yes, you CAN use a computer to calculate how your nuclear arsenal is deteriorating. What makes you think they can't?
They rely on the resonant frequency of atoms in metal vapors (Cesium or Rubidium), or the output of a hydrogen maser.
http://en.wikipedia.org/wiki/Atomic_clock
Radioactive decay is a chaotic process. So chaotic that it can be used as the basis for a random number generator. Just what you DON'T want in a precise time/frequency reference.
http://www.fourmilab.ch/hotbits/
Remember "News for Nerds, Stuff that Matters"? Help make it a reality again! http://soylentnews.org
Atomic clocks have absolutely nothing to do with radioactive decay. http://en.wikipedia.org/wiki/Atomic_clock
The fact that the result was displayed on a graph of 200 pixels for a summary for the public has jack to do with the production use of the data. Do you think businesses only produce reports for the shareholder meetings and banks only look at pie charts for making decisions on billions of dollars of assets. Your criticism is disingenuous at best and has nothing to do with the working product of the supercomputer.
As for the degrees of freedom, you have to recall that their working needs are different from yours. They require greater accuracy and the ability to work within a given time frame in a logistically workable manner. They took advantage of the resources they had and got the greatest level of accuracy they could by using all of those resources. In other words they wrote their program to take full advantage of the supercomputer that they had at their disposal.
Your also assuming that the single given job you have chosen to criticize is the only job that the supercomputer runs, which is a foolish assumption when you would know that the supercomputer runs many types of jobs. In this case the job represented is one that can take advantage of the DOE's available resources for a given problem, and be safely declassified for public consumption. Do you think the people working on this are going to throw away their career and go to prison to make a point on Slashdot?
I get the impression you have never worked with large scale computing needs and have only ever worked in a math lab in a University somewhere.
I know I shouldn't respond to AC's but I'm going to anyway:
And it didn't need to be.
As far as geometry goes, it did need to be that detailed. Firstly, the pellets are round and to get the power and heat transfer correct you have to get the geometry correct. Also, pellets have small features on them (dishes on top and chamfers around the edges) that are put there on purpose and make a big difference in the overall response of the system (the dishes, in particular, reduce the axial expansion by a lot). So the detailed geometry is a very important part of this simulation. But that's not the only reason why it's large.
Your simulating a simple heat transfer and simple expansion, NOTHING MORE, no different that any other chemical process simulation in any other factory. Just with a lot more nodes.
I already explained how that is not the case. These are fully-coupled, fully-implicit multiphysics calculations. It is _not_ just heat conduction going on. Very complicated processes like fission gas creation, migration and release and fission induced and thermal creep, and fission product swelling are all involved. Plus the heat conduction and solid mechanics and thermal contact and mechanical contact and fluid flow model (on the outside of the pin) and conjugate heat transfer. All of these processes feed and are impacted by each other. These are NOT simple calculations.
It's also an arbitrary simulation serving no purpose. You said "what is that panel is broken right there' then ran a simulation with a stupid number of nodes to soak up a computer. But the pellet was made, it exists, it didn't need your simulation to be made and the simulation make zippo difference. You can run any number of similar simulations with the damage in an infinite number of places or combination of places, and it makes zip difference to the world because you don't know where each pellet is damaged. So NONE of your simulations apply to the actual pellet.
Actually, you are very wrong. Firstly, the Missing Pellet Surface problem is a huge problem in industry. What we can do with simulation is explore boundaries of how much tolerance there can be for such missing surfaces. We can vary the missing surface size and run thousands of calculations to determine the sizes that operators need to worry about. They can then adjust their QA practices to take this information into account. We can also run simulations of full reactors and stochastically sprinkle in defect pellets and show the overall response of the system which can help in understanding how to bring a reactor back up to full power in a safe way after refueling.
As for "that pellet exists"... firstly that's not true... but even if it did, doing experiments with nuclear fuel is _very_ costly and takes years (that is something else we do at INL) in order to better target our experimental money we do simulation to guide the experiments.
Their mission statement is absolutely clear. Turn cold war spending into security theatre spending and that's your job.
I don't work in security.... there are many national labs, all with different missions, but they _all_ do non-security work. They all work with US industry to solve some of the toughest problems on the planet. They are all full of extremely smart people and they are all working to add to the competitive advantage of the US. I'm sorry that you feel that way, but if you are interested in learning more about the national labs you should get a hold of me.