Titan (United States)
One of the two Cray systems on the List, the Titan lives up to its name, utilizing Opteron 6274 16-core 2.2GHz processors along with NVIDIA GPUs to perform at an amazing 17.6 petaflops on around 561,000 cores. It's located at the Oak Ridge National Laboratory (ORNL) run by the Oak Ridge Leadership Computing Facility (OLCF). Titan nabbed the No. 1 spot on the Top500 the month after it was deployed in late 2012, but dropped down to No. 2 in the June 2013 rankings, where it remains.
Titan is technically a major upgrade to the ORNL's previous supercomputer, Jaguar. Due to its novel hybrid architecture, Titan fits into the same cabinets as Jaguar while achieving nine times Jaguar's speed with only around a 60 percent increase in energy consumption.
Titan is one of two supercomputers in the top 10 that incorporates NVIDIA GPUs to increase performance while keeping the power consumption lower than it would be for a similarly powerful all-CPU system. Utilizing the GPUs to run applications at the speed of which the system is capable requires a new approach to programming its software, however. To address this, the OLCF has partnered with Cray and NVIDIA to create the Center for Accelerated Application Readiness (CAAR), which is hard at work coming up with best practices for code development.
As with Mira, researchers can submit proposals through the U.S. Department of Energy's INCITE program to earn time on this workhorse.