by Michael Feldman, HPCwire Editor
With all the recent hoopla about GPGPU acceleration in high performance computing, it’s easy to forget that Roadrunner, the most powerful supercomputer in the world, is based on a different brand of accelerator. The machine at Los Alamos National Laboratory uses 12,960 IBM PowerXCell 8i CPUs hooked up to 6,480 AMD Opteron dual-core processors to deliver 1.1 petaflop performance on Linpack.
Because of the wide disparity in floating point performance between the PowerXCell 8i processor and the Opteron, the vast majority of Roadrunner’s floating point capability resides with the Cell processors. Each PowerXCell 8i delivers over 100 double precision gigaflops per chip, which means the Opteron only contributes about 3 percent of the FLOPS of the hybrid supercomputer.


