IBM-Based Systems Top List of 'Greenest' Supercomputers
The latest iteration of the Green500
was released at the SC08 supercomputing conference in Austin, Texas.
It is the first time high-performance computers have executed more than 500
million floating-point operations/sec (megaflops) for every watt of energy they
used, according to the list's compilers.
The most energy-efficient supercomputer is a 2,016-processor machine at the
University of Warsaw's Interdisciplinary Centre
for Mathematical and Computational Modeling. The system, based on IBM BladeCenter
QS22 servers, produced more than 536 megaflops per watt.
That system and the next six systems on the list run IBM's multicore Cell Broadband
Engine (Cell/B.E.) processor. Four of those systems use IBM's new QS22 blade
server. The top four machines all achieved more than 500 megaflops per watt.
Overall, the participating supercomputers showed a 17 percent increase in energy
efficiency since the last edition of the ranking, released in June.
Wu Feng and Kirk Cameron, associate professors at Virginia Tech, started the
Green500 in 2006 as a way to encourage supercomputer developers to think more
about the amount of energy their creations consume. In the past few years, supercomputer
managers have started to notice that the increasing size of their machines brought
about a corresponding increase in energy bills.
"For decades now, the notion of performance has been synonymous with speed,"
the Green500 Web site states. "This particular focus has led to the emergence
of supercomputers that consume egregious amounts of electrical power and produce
so much heat that extravagant cooling facilities must be constructed to ensure
The Green500 list is compiled from the biannual Top500 list of supercomputers,
the latest iteration of which was released earlier.
Top500 participants were encouraged to submit data on the average amount of
energy their systems used during a Linpack run, a benchmark that determines
their rankings on the Top500. Positions on the Green500 are calculated by dividing
the Linpack score, measured in flops, by the average amount of wattage used
during the testing.
In the latest Green500 compilation, 276 of the top 500 sites submitted their
energy usage, a 19.5 percent increase from the number of submissions in June.
The list's compilers estimated the rest of the scores.
Joab Jackson is the chief technology editor of Government Computing News (GCN.com).