Efficient Supercomputing with Green Destiny

gManZboy writes: "Is it an oxymoron to have an efficient supercomputer? Wu-Chun Feng (Los Alamos National Laboratory) doesn't believe so - Green Destiny and its children are Transmeta-based supercomputers that Wu thinks are fast enough, at a fraction of the heat/energy/cost, according to ACM Queue." 240 processors running under 5.2kW (or less!) is nothing to sneeze at. The article offers up this question: might there be other metrics that might be important to supercomputing, rather than relying solely on processing speed?

Comments

Old age question for a new generation

[mrnick]

The MHZ war has been going on for soooo long that everyone just excepted that faster MHZ related to faster machines. Well, 64Bit computers are placing chip manufactures in a position where they have to market on a platform that declares that MHZ doesn't really matter.

I think the question is a bit naive though as everyone knows a hundred software tools to rate performance of CPUs rather than just relying on MHZ.

Nick Powers

Re:Old age question for a new generation

[SiliBelgian]

Now most people who buy a car are more concerned with other features - passenger comfort, style, efficiency.

What ever happened to safety?


Computer manufacturers are only just starting to see this, making smaller, quieter, cooler-running machines. Hopefully they'll continue to look at what their customers actually need rather than simply putting out chips with higher clock speeds.

You are talking about computer manufacturers as if they are all in the same business. It's the chipset manufacturers that continue to put out faster and (hopefully) more efficient chipsets and CPU's (which is exactly what they are supposed to do).
On the other hand there are the ready-made PC assemblers like Compaq, Dell, Fujitsu,... These are the ones deciding whether their products will become smaller, quieter, cooler-running or not. There's plenty of small, well-designed cases and silent coolers (or water-cooling systems) available out there for them, which are of course a bit more expensive then ordinary stuff. Untill recently however, most assemblers would simply choose to save as much money as possible on cables, coolers, cases and those other parts that keep a PC together, to spend it on the newest fastest Intel-CPU. In this way, they were (are) able to offer their customers a big ugly noisy power-draining PC that goes way too fast for their use anyway (MSN chatting mostly) for an affordable price.


I would guess this is a shift from car-oriented people buying cars to everyone buying cars as they became more of a necessity.

I'm not really old enough to remember car history (or computer history for that matter), but if that's true, you are 100% correct.

Does it really save that much power?

[toddestan]

I was talking to a friend the other day about a bunch of lab computers that my school is getting rid of - a bunch of old Pentium MMX's. He suggested turning them into a cluster. But after thinking about it, I realized that the group of about 10 old computers we had would consume more power - and would likely be considerably slower than a single one of the 2.4Ghz Dell's that replaced them. "What's the point?" I said.

Applying that here, the little VIA chips run at roughly the speed of a Celeron 500 or so, I'd say something like an AMD Athlon 3GHz would be just about as fast as about 6 of the VIA chips. So you are still saving some power, but as not as much as it would seem as first, as you need many low power chips to equal the speed of one faster chip. Not to mention power consumed by having more motherboards, network cards, switches, and other associated hardware.

Something to really look at is the cluster of G5's. The G5 chips use a lot less power than their x86 counterparts. I bet that cluster of G5's is probably right up there in terms of processing power per watt as this VIA super computer. And it's way more cool to boot.

Do the math

[InodoroPereyra]

This is very, very cool. For one thing, a bottleneck in supercomputers is in most cases the network. In this regard, dropping some per/node performance might not affect the overall performance for applications that need intensive interprocess communication.

The other point is: how expensive it is to support a cluster ? Not only the energy consumption, but also the infraestructure. It is pretty darn difficult to keep a thousand processors cold. You may need a special building, special power supply for it, etc.

A final point: as far as I know, the rule of thumb is that the floating point performance with these energy efficient processors is of the same order of magnitude as regular processor, may be a factor 2 difference.

You do the math ... :-)

Re:Do the math

[Jeff DeMaagd]

My question is whether this is more efficient per TFLOP than IBM's PPC unit, which is IIRC smaller than a rack and houses 1024 PPC chips.

I really can't tell now that the site is slashdotted. The CPU in this case can't be that much of a burden if they run around five watts. I am curious if 80% of the heat generated here is simply networking.

Re:Green Destiny

[ArgoTango]

Robert Cringely pointed out the benefits of this tradeoff (pure speed vs. low heat/hihg maintainability), pointing to Google's use of Pentium III-s for their server farms.

Nano-ITX

[PureFiction]

with the centaur C5P processor core. Draws about 8W for the chip @ 1Ghz. Lets assume 12W total for network boot.

[ see image here: peertech.org/hardware/viarng/image/nano-itx-c5p.jp g ]

With 5,200 Watts for Green Destiny, you could use 433 boards these boards for the same power consumption.

The on chip AES is clocked at 12.5Gbps, Entropy at 10Mbps (whitened). Thus you would have

422Ghz of C5 processor power
5.412TB/s of AES (yes, terabytes)
4.22Gbps of true random number generation.

Yeah, these are really rough estimates, but that is a long of bang for your kilowatt buck no matter how you slice it.

With a cutting edge P4 approaching 100W the efficiency of these less powerful but fully capable systems will become increasingly attractive.

I would not be surprised to find bleeding edge processors relegated to gamers and workstations as most computing tasks start migrating towards small, silent, low power systems that simply *work* without eating up desk space, filling a room with fan noise and driving the electricity bill higher with continuous 100's of W draw.

Memory Speed

[rf0]

Its not CPU speed that is important in supercomputer/clusters it is the speed at which you can get data from one node to esp memory access. If you havea 512 node system and node 3 needs a copy of node 40's memory it has to copy it over.

If its even just 512Mb of Gigabit ethernet and assuming 100% performace it would still take 5 seconds which is many orders of magniture. Just look at SGI machines which use NUMA and their Cray-Linux are 3.2 TeraBytes (bytes not bits). Now thats how you want to shift data

Rus

Re:WTF?

[Anonymous Coward]

No, supercomputers that can do a lot of image processing cannot waste power simply because it might be available.

Modest supercomputers are used in the military on airframes. Power consumption is important for at least two reasons. First is the wattage and power draw. Second, and more subtle, it that the cooling requirements while flying at high altitude become more important than simple fan noise. Pentiums burn up no matter what you do. PowerPCs@10Watts with conduction cooling will survive.

Less heating=Denser packing

[gabbarbhai]

If one can pack the processors more densely, it would cut down on the wiring etc, or allow much shorter paths between nodes (better still, one might be able to stuff many processors on the same board or something), thereby increasing bandwidths (when you try to increase bus speed, path length and related current leakages etc do pose problems). This in turn means computations that require more 'random' communication between nodes can speed up. I suppose that's definitely worth pursuing for the more fine-grain computation where communication bandwitdh is the bottleneck.

Why does a supercomputer need x86 compatibility?

[hoof]

That is the only advantage of using a Transmeta CPU. Wouldn't it be more efficient to just use a regular VLIW CPU without all the x86 code morphing stuff?

G5 = HOT

[TubeSteak]

Article

Running 1,100 computers in a 3,000-square-foot (280-sq-metres) area sends the air temperature well over 100 degrees Fahrenheit (38 Celsius).

The heat is so intense that ordinary air conditioning units would have resulted in 60-mph (95 km/h) winds. Specialised heat exchange cooling units were built that pipe chilled water into the facility.

"There are two chillers for this project," explained Kevin Shinpaugh, Director of Cluster Computing.

"They're rated 125 tonnes each in cooling capacity, and they pump 750 gallons per minute each. The water is at about 45 degrees Fahrenheit."

The power supply was another huge challenge. The supercomputer uses the same amount of electricity as 3,000 average sized homes.

I think the idea behind using low heat output CPUs is that you'll save money in other places. Its a trade off of sorts. More processors, but less expenses on cooling and power. I agree that power consumption by peripherals needs to be looked at too. To be fair to the G5, the AMD64 processors run about 2x as hot.

I'd like to see an analysis that allows you to cost (i'd say price, but its not just about money) the different components of a supercomputer and account for things like power, cooling, weight, size, infrastructure etc. The factors would have to be weightable so that you can assign varying levels of importance(like if space is more precious than money). It wouldn't need to be indepth or terribly exact, but i think it would help bring out the best possible choices.

Re:Money is finite too

[TubeSteak]

Commercial, Industrial & Institutional entities usually get a nice big fat discount on power and water. That said, your comments dovetail nicely with this article I just read.

At Penn State University, electrical consumption in October was 33 million kilowatt hours, up from 27 million in October 1996. The school's electric bill is about $1 million a month. Paul Ruskin, with the university's physical-plant office, said power use by the 13,000 student residents contributed to the increase. Some officials say higher energy costs, campus expansions, lighting and the addition of computer labs and other energy-eating facilities are more to blame for increased power demand than student appliances.

Later on they talk about the costs of upgrading the electrical systems in dorms/buildings built during the 1950s & 60s which can't handle the loads being placed on them. At some point, power consumption will have to stop increasing or massive upgrades to the basic infrastructures will be needed (see the blackout of 2003 for reference)

Re:Indeed...

[sam0ht]

I'm more curious about the heat output (I know the figures cited in the original article referred to power consumption, but heat was mentioned)

The heat output is precisely the same as the power input. All electrical power used by the PC is eventually converted into heat in the room, so a 450W PC consumes 450W of electricity and provides 450W of heat.

Incidentally, if you have a 500W heater in your room, you could replace it with a 500W PC for no extra electrical cost, and the same effect in terms of keeping you warm. Heat can be a good thing !