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Virginia Tech to Build Top 5 Supercomputer?
hype7 writes "ThinkSecret is running a story which might explain exactly why the Dual 2GHz G5 machines have been delayed to the customers that ordered them minutes after the keynote was delivered. Apparently, Virginia Tech has plans to build a G5 cluster of 1100 units. If it manages to complete the cluster before the cut-off date, it will score a Top 5 rank in the Linpack Top 500 Supercomputer List. Both Apple and the University are playing mum on the issue, but there's talk of it all over the campus."
Virginia Tech placed the dual-2GHz G5 order shortly after the G5 was announced. Multiple sources said Virginia Tech has ordered 1100 units
:-)
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Wow, that'll make Apple's quarter for sure
Seriously though, why PowerMacs ? I've always been under the impression that intelloid machines are the cheapest commodity hardware around for equivalent processing power, if not the most exciting. Would anybody know why Powermac G5s are a better choice here?
(Note to computer zealots: it's not a flamebait, it's a genuine question, from someone who is rigorously ignorant of the Mac world. And just in case, the first sentence is a joke, too
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
Who builds 2-8K processors in a box? Have you thought for a second what it might take to power or cool this? Or if it could be wired? The actual engineering of actually doing this are much more challenging than talking crap on Slashdot.
You win the moron of the article award. Congrats.
The article makes no mention of the operating system that will be running on this supercomputer. I for one would like to see them get this done w/ OS X rather than use GNU/Linux.
[Connection closed by foreign host]
Currently the top 5 consist of 4 machines that have a Therotical maximum speed (Rmax) the are larger then the 10TFLOPS this machine will have. Then you have to translate that into peak speed which is what matter and what this list uses to rank the machines. Peak will be a good deal less, but this mostly has to do with the way the systems are interconnected and not the machines themselves. Say what you may about the G5 but the interconnect is more important.
There is only one machine in the top 5 that this cluster could beat. The rest of the world has had 6 months to build machines too.
This should be a top 10 machine for sure. Good to see more fast machines being built every day.
Several years ago I did some work on some Virginia Tech "supercomputers" (actually, baby versions of ones on campus that were the same as huge ones they leased time on elsewhere), and I think the people talking about Altivec are on track. I never knew exactly what they did, but at that time the Math, CS, and Engineering groups were working together to simulate wing designs for the YF-22 jet figher prototype. Since I was more of a "sysadmin" (althoug h with a math and CS background) I ignored most of what was going on, but one thing I can tell you was vectors, vectors, and more vectors. The vector is king. It's an assumption, but I'll bet they are still working on similar type studies, and if built, this will be just the beast for it.
Actually, the amount of cache coherency checking needed in a large shared memory machine drives the latency right up. Besides, myrinet is ~15 usec latency. That's pretty goot for most things.
While the AltiVec unit is very impressive, The SSE2 unit on the P4 or the Opteron would have nearly the same performance and cost a whole heck of a lot less (I am betting if this rumor is true at all, then Apple has given the units to the school).
What I am wondering is, what OS is this cluster going to run? I mean, have the BSD folks figured out how to scale? No chance it will be OS X...maybe AIX?
[RIAA] says its concern is artists. That's true, in just the sense that a cattle rancher is concerned about its cattle.
The grant money that flows into a public research and occasionally teaching institution can be stagering, and absolutely dwarf the money students pay in tuition (sometimes by a factor of 10!). A better question might be, why don't the gradstudents donating their labor, possibly to patents that will be controlled by the university, recieve more consideration, and fair labor law protections.
But I would bet this will be not too dissimilar in use from the HP Itanium2 referenced earlier on slashdot. I would bet one of the paramount concerns this cluster would look at is the effect of farm runoff, and probably climatology too among other things.
--Jimmy has fancy plans; and pants to match.
With 1100 machines in the cluster, there must be _at least_ 2200 DIMMs. Since these must be 400MHz (PC3200) DDR, they can't be on a large 0.15 micron DRAM process, but most likely between 0.11 and 0.13u.
d /d imm_results.htm
Who cares?
APPLE G5'S DO NOT SUPPORT ECC.
The random bit error rate for 2200 DIMMs with 0.13u cells is roughly one '1' bit dropped to '0' every 9 hours. In other words: good luck getting any reliable, large-scale computation done with this cluster. (And I do mean "good luck" - they might get a run of two or three days without any problems once in a while.)
Now if only Apple would support PC3200 ECC DIMMS, which certainly do exist:
http://www.intel.com/technology/memory/ddr/vali
this cluster might be a bit more useful for real work.
I wonder if any universities have tried to write a distributed computing app along the lines of seti. Require it to connect to the university network, it grabs itself maybe 50 megs of hd space, and a fraction of all the new computers people bring to campus, in addition to all the computer lab gear belong to their massive number crunching problems. Make another version available to alumni, or even institutions as some form of corporate sponsorship.
Then if it got popular, and they were really clever, they could sell off a part of that computational power they amassed to solve other peoples problems providing for funding for new versions and new supercomputing clusters.
--Jimmy has fancy plans; and pants to match.
It's not just a campus rumor. I attended an informational meeting about it today (which was actually postponed when I got there, so there will be another one soon). Basically, they are recruiting a few computer geeks here at Tech to help set it up and all. Should be fun :P
Stephen
Fault loves the past, worry loves the future, but content enjoys the present.
Latency is paramount for some tasks, less important for those that *can* make a good distributed project over the Internet of today.
Now, since today's supercomputers are *all* massively parallel constructions, the difference between a commercial design and an off-the-shelf cluster is in the quality and speed of the interconnects. NEC's Earth Simulator, the prime example of 'custom' supercomputer architecture, puts many processor units on *ridiculously* fast 'local' buses, and its racks are all interconnected with still_pretty_insanely_fast (and rather expensive) custom links.
Meanwhile, more 'commercial' designs use various interconnects. IIRC, NEC's 'regular' supercomputers, which formed the design basis for the Earth Simulator architecture, use Fibre Channel 'mesh' networks between racks. The Opteron - sure to be an up-and-coming player in this market - offers HyperTransport, which it looks like Cray will be stretching to its limits on Red Storm; I'm not sure *how* long an HT bus can be, but one gets the impression they'll be stretching it as far as possible, and it's certainly high throughput/low-latency versus the technologies you'd usually find in use for 'networking.'
Anyhow, point is, those designs pack a lot of CPUs together with *very* fast interconnects (equivalent to 16, 32, 64+-way SMP), and have lots and lots of racks of those. (The Opteron/Red Storm approach sounds sexy to me, because I think Hypertransport should let them pack 'lots and lots' of CPUs together versus existing designs. I've yet to read anything about what they're actually doing with it, though.)
Now.. In contrast, an 'off the shelf' cluster is usually going to stick with Ethernet, and will only have 1 to perhaps 4 processors per [node-unit-where-the-CPUs-are-connected-on-a-fast- local-bus], depending how affordable 'cheap' multiprocessor systems are at the time. But *everyone* building supercomputers bumps up against the latency/routing problem; it's just a question of whether it's a problem for, say, 50 Earth Simulator racks (aren't there quite a few more?) vs. 1100 PowerMacs. Experimenting with 'lots of little nodes' has led us to better understand the problem, and learn how to produce tuned topologies that can compete favorably with 'purpose-built' hardware. See: http://aggregate.org/KASY0/
Now, the question *is* one of cost-benefit. Large supercomputers tend to be built with maintenance features and power efficiency in mind. In turn, a totally 'off the shelf' cluster like KASY0 has some advantages because each machine is a cheap, practically disposable 'module' unto itself, and can doubtless be downed off the cluster, pulled out and replaced with another while being easily bench-repaired (since, after all, it's a self-contained PC, rather than a CPU blade or some other random card that would require an expensive test rack to troubleshoot). Meanwhile, if you absolutely demand low-latency, you want one sort of design (Red Storm seems to be acheiving it 'on the cheap,' by combining off-the-shelf - and thus cheap - chips and buses with smart 'custom-design' engineering) while if you can sacrifice some for throughput (jobs with few conditionals), you want another... (like 1100 G5 Macs on a shelf, wired with 'boring' gigabit ethernet, especially if Apple is giving you a bulk discount on the hardware).
So what I'm trying to say is... this is a *combination* of PR stunt and intelligent planning, and there's certainly a lot of 'good science' they could do with the beast - both in number-crunching and 'computer science' a-la cluster topologies. Whether they'll actually *use* it for such, or if it'll be solely a topology toy is anyone's guess.
I think there's some hope that it'll be the "Real Thing," though, since this would explain some of the weird rumors about FC-on-the-mainboard Macs. So they get a Real Monster, made of what will be revealed as "the new G5 Xserves" at the unveiling. The best of COTS *and* fresh d
i would take this story to imply that a G5 powered Xserve is not going to be shipping anytime soon..... the Xserve is made to cluster and run in situations like this. i guess the rumor sites can speculate if it's G5 parts available or some other holdup on a G5 Xserve.
/. a year or so ago about a group that went from building a rack and unboxing their G4s to a running cluster in part of a day. i really don't remember the specifics but i think it was something like 30 G4s? i would guess the G5 is not that much harder... and they seem to have Apple helping. maybe they hooked up the optical cards from the Xserve...... we'll see i guess.
unless there is some reason the desktops are better for this project that i did not pick up on?
as for the above question about Macs.... depending on what they want to really do with this, Altivec is really efficient for some computations. all flame wars aside there have always been people clustering Macs for certain uses. i do not know how much of it was user preference or the software they wanted to run or the simplicity of getting the cluster running.
it is supposedly VERY simple to cluster Macs. there was a story on
Or how about this: your bandwidth is dependent upon the amount you contribute to the distributed processing.
Hopefully there would be some sort of minimum service level, maybe 64kbps; presumably people dropping tens of thousands expect at least a modicum of return on their investment. People who didn't want to install the client could trudge along at those speeds.
Eventually there would be a market system, whereby people would trade their completed blocks for other commodities, like food vouchers, prints, copies, cash, and sexual favours.
Good luck and godspeed,
Branch
It's just too darn hard to make a shared memory computer with 1000's of processors. So the common architecture is to make a cluster of smaller shared memory machines.
It's hard, but not too hard or impossible. The Silicon Graphics Origin 3000 supports 512 processors in a single image system with the stock IRIX kernel and 1024 processors with the "XXL" kernel.
Rumor has it Origin 4000 will support 2048 processors, as will Altix once SGI has done some major work with their kernel patches. (Altix is currently limited to 64 processors per system image).