In the newest version of the semiannual Top500 list, Linux continues to dominate as the operating system of choice for the world's most advanced supercomputers. According to the latest list, compiled by compiled by Hans Meuer of the University of Mannheim, Germany; Erich Strohmaier and Horst Simon of NERSC/Lawrence Berkeley National Laboratory; and Jack Dongarra of the University of Tennessee, Knoxville, more than 90% of the Top500 fastest supercomputers run some version of Linux.

In further evidence pointing to the dominance of Linux in high-performance computing, the National Center for Supercomputing Applications (NCSA) has selected Linux as the operating system for the multi-petaflop IBM POWER7-based Blue Waters supercomputer that will come online in 2011. Blue Waters is based on the most advanced technologies under development at IBM, which are embodied in the PERCS (Productive, Easy-to-use, Reliable Computing System) system design. The development of PERCS is supported by the Defense Advanced Research Projects Agency (DARPA) High Productivity Computing Systems (HPCS) program.