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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?
I knew that sword was beefy, but that's insane!
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 ... :-)
Why are supercomputers primarily benchmarked by their speed? The answer comes when you consider that almost all labour-saving devices are measured in the work they perform in a given period of time.
Time is the only truly finite resource from a human perspective. As technology has progressed, distances have been conquered, vast energies harnessed, but old Father Time is still inescapable.
As a result, we place great value on just how much time is taken to accomplish anything.
You're comparing apples to oranges, not to mention that your info's a little off...
1) A Nehemiah core C3 runs really close to the same performance of a comparably clocked Celeron, with the same general power consumption of a Samuel2 core (For those that don't know, part of how VIA's chip originally got it's low power is that the FPU was underclocked by a factor of 1/2). It's a nice chip overall, but it's not really intended (nor are they USING it that way) for scientific or gaming applications even though you can use it for that. The C3's winning usages is in something like a media PC, workgroup servers, and embedded systems where you need low power consumption, relatively low cost, and relatively high performance compared to other x86 embedded solutions.
2) The Crusoe and similar chips are very fast executing VLIW CPUs (very much like the Itanium...) that have code morphing that translates x86-32 instructions into comparable sets of instructions for the VLIW CPU- in fact it's very good at doing this sort of thing. The reason it's less desirable with a desktop or gaming application is that you're exceeding the VLIW code cache regularly, meaning you have to keep recompiling the x86 instructions into the native VLIW ones. For a scientific application, the same task gets executed time and time again and usually ends up with most, if not all, of the code in the pre-morphed code cache. At that point, you're now in the high-performance domain with very little power consumption. The Crusoe in this application would consume less power than the G5 and run just as fast. (Check the article that you're commenting on...)
Do some thinking outside of the box here, what's good or great on a desktop machine isn't always the optimal choice for supercomputing clusters or HA clusters. Depends on a bunch of factors, including what you're going to be running on the systems in question and what kind of environmental conditions you're going to be facing.
I am not merely a "consumer" or a "taxpayer". I am a Citizen of the State of Texas
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.