The fastest supercomputers today

Measuring supercomputer speed

In general, the speed of a supercomputer is measured in "FLOPS" (FLoating Point Operations Per Second), commonly used with an SI prefix such as tera-, combined into the shorthand "TFLOPS" (10¹² FLOPS, pronounced teraflops), or peta-, combined into the shorthand "PFLOPS" (10¹⁵ FLOPS, pronounced petaflops.) This measurement is based on a particular benchmark, which does LU decomposition of a large matrix. This mimics a class of real-world problems, but is significantly easier to compute than a majority of actual real-world problems.
"Petascale" supercomputers can process one quadrilion (10¹⁵) (1000 trillion) FLOPS. Exascale is computing performance in the exaflops range. An exaflop is one quintillion (10¹⁸) FLOPS (one million teraflops).

The Top500 list

Main article: TOP500

Since 1993, the fastest supercomputers have been ranked on the Top500 list according to their LINPACK benchmark results. The list does not claim to be unbiased or definitive, but it is a widely cited current definition of the "fastest" supercomputer available at any given time.

Current fastest supercomputer system

A Blue Gene/P node card

In November 2009, the AMD Opteron-based Cray XT5 Jaguar at the Oak Ridge National Laboratory was announced as the fastest operational supercomputer, with a sustained processing rate of 1.759 PFLOPS.