Supercomputers Get Eco-Aware

Twice a year, the computing world waits to hear whose processors and which vendors will claim the equivalent of a gold medal for building one of the world’s fastest supercomputers as measured by the Top 500 nonprofit. This year it was IBM’s $100 million Roadrunner machine, which can reach speeds of 1 petaflop (about 1,000 trillion calculations per second). It also consumes a whopping 3 megawatts of power.

But today’s is the first Top 500 list to ever track power consumption of these machines and the results are only semi-encouraging. The fastest computers, surprisingly, do not consume the most power. The average power consumption of a Top 10 system is 1.32 megawatt and the average power efficiency is 248 megaflops per watt.

Older machines on the list are using more less power, but are just not as efficient. The average supercomputer on the Top 500 list has a power efficiency of 122 megaflops per watt. (The press release also says the average consumption of a Top 500 supercomputer is 257 megawatts — we’re pretty sure they mean 2.57 megawatts, but we’re waiting to hear back on that.) Update: They got back to us to tell us that the average Top 500 power consumption is actually 257 kilowatts. That actually gives me hope that all the energy-efficient chips coming out recently can help this problem.

Ironically, many of these computers are engaged in the very types of climate modeling programs or protein folding operations that could one day help the environment. It’s encouraging to see that the number of calculations per watt is trending up and that average power consumption seems to be trending down with newer machines at the top of the list.

However, the demand for power in these computers is crazy high (for comparison, an average desktop consumes about 80 to 150 watts), which explains why scientists at the Department of Energy’s Lawrence Berkeley National Lab are hoping to figure out a more energy efficient way to build a supercomputer using embedded processors.