No, not the candy bar (though I could really go for a Milky Way Midnight bar right now). I'm thinking of the Milky Way 2 (Tianhe-2) computer system at the National Supercomputing Center in Guangzhou China. This machine incorporates 32,000 12-core Intel Xeon processors (E5-2600 v2) and 48,000 Intel Xeon Phi coprocessors. It has been declared the fastest computer on the planet (maybe even the galaxy?) as it sits on top of the June 2013 TOP500 list of supercomputer systems released at the ISC2013 conference.
This is the second time a Chinese system has occupied the number one slot on a TOP500 list. The system achieved a computation speed of 33.2 Petaflops on the Linpack benchmark. The first China system to reach the number one position on the list was in November 2010 when the Tianhe-1A system was able to attain 2.57 petaflop/s. That system used over 14,000 Intel Xeon processors and over 7000 NVIDIA Tesla GPUs.
Comparing these two machines shows off the latest trend in achieving top-notch performance in HPC computations: the use of accelerators. There is an increase of 13X in the petaflop/s rate in the 31 months between the appearance of Tianhe-1A and Tianhe-2 on the lists. From the “rule of thumb” guidance attributed to Gordon Moore, one might have expected an increase around 4X. Between the two generations of Tianhe, there has been a doubling of the number of processors and almost a 7X increase in the number of accelerator resources incorporated. I think this has more to do with the performance differences than just the raw increase in number of processors and cores. As we march toward exascale machines, I believe the use of accelerator technology will become more common.
One other point I’d like to note is the energy efficiency of the top machines. The number 2 system on the most recent list, Titan at Oak Ridge National Laboratory, has a power rating of 8.2MW. The Tianhe-2 system uses about twice that much power and achieves almost two times the petaflop/s. I can only imagine that the flops per watt rating of future machines will increase as processor manufacturers release even more power efficient chips in the coming years.