Despite growing alarm over spiraling datacenter power consumption, this spring's Green500 ranking of the world's most sustainable publicly known supercomputers shows that the same energy-hungry server accelerators behind the AI boom are also driving sizable improvements in efficiency.
In early 2022, the most efficient system on the Green500 was the Frontier TDS testbed, a smaller version of the Top500's number-one-ranked 1.2 exaFLOPS Frontier machine that made its debut that same year. In fact the full Frontier system ranked number two at 52.2 GFLOPS/watt behind its the testbed at 62.7 GFLOPS/Watt.
This spring's Green500 also sees AMD's Instinct-based systems slip further down the list. Just three of the top 10 most efficient supers are powered by AMD accelerators including Frontier TDS in seventh, Adastra in ninth, and Setonix GPU in tenth. This suggests we may see improvements in efficiency moving to faster networking gear. Until recently, PCIe 4.0 based CPUs limited interconnect bandwidth to 200 Gb/s per port. However with PCIe 5.