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Earth Simulator, G5 Cluster Drop In 'Top 500' List
daveschroeder writes "The November Top 500 supercomputer list has been published at SC2004. Topping the charts is IBM and the US Department of Energy's 'BlueGene/L DD2' beta system, at 70.72 TFlops, followed by NASA's 'Columbia' at 51.87.TFlops. For the first time in several publications of this list, Japan's Earth Simulator is no longer in the number one slot, falling to third. Virginia Tech's 'System X' Xserve G5 cluster, while 20% faster than the original cluster that debuted at number 3 last November, has fallen to number 7 due to the new entries, but remains the fastest supercomputer at an academic institution. Here's an excellent cost comparison (Google cache) of the top machines ('System X' is significantly cheaper than anything else in the top 20, not to mention cheaper than many things far below it in performance)."
It is actually 6 of the top 10, and 13 of the top 25.
I think it is interesting that 11% of the top 500 are Power architecture, and 64% of the top 500 are intel based systems. Yet 50% of the top 10 are Power architecture and only 20% of the top 10 are intel architecture. Also interesting is that the Power based systems seem to have twice the Mflop/dollar ratio over the intel systems.
That's easy...the Xserve G5s consume a LOT less power (and therefore generate less heat, resulting in lower cooling costs) than any competitive products (Xeon, Itanium2, Opteron)...and this was true even when they were using the 970 (as opposed to the 970fx they are using now).
Several of the researchers at Virginia Tech have referred to this in various news stories numerous times - one estimate was over two times less power than comparable systems.
It's not even technically on campus. Its at the nearby Virginia Tech Corporate Research Facility. And in any case, you can arrange a tour if you want.
A major cost is power and cooling requirements. According to Apple, a single drive, dual processor 2.0GHz XServe will use about 250W peak. Virginia Tech has 2.3GHz machines and Infiniband PCI-X cards. There's also networking gear and other support equipment to consider. So, we'll use a high figure of 350W per node, giving us a 40% overhead. As for heat production, same overhead, 1200BTU/h per node.
We're going to consider the worst-case scenario, under which we have a 100% load, year round, on all 1100 nodes. That gives us a power consumption of 385kW and 1320kBTU/h of heat generation.
Now, we need to get rid of that heat, and that's going to require a lot of power. My research indicates up to 300kW may be required, but that's a high number and actual requirements may be lower.
So, here we are, with 685kW required for power and cooling. That means a 6000MW/h a year.
Now, the cost of power is high, since you need to amortize and maintain the UPS equipment and the generators. We'll use a figure of 0.15$/kW/h, or 150$/MW/h. Very generous.
So here we are. The absolute worst case for power and cooling. Full load, year round, expensive cooling, overpriced power and amortized UPS and generators.
900 000$/yr. Below a million. It's not that bad, is it ? The real cost is likely below a half-million.
As for the rest, well, how much pizza is really required to entice graduate students and professors to work on that machine ?