ASCI Red run on different operating systems. For example, users of the computer work in an environment called "Teraflops OS", an operating system (once called Paragon OS) that was originally developed for the Intel Paragon XP/S Supercomputer. ASCI Red's Compute partition runs on an operating system named Cougar. Cougar is a Sandia Labs and University of New Mexico collaboration; it is a lightweight OS based on PUMA and SUNMOS, two systems that were also designed for use on the Paragon supercomputer. It consists of a light weight kernel, the Process Control Thread, and other utilities and libraries. The Linux 2.4 kernel was ported to the system and a custom CNIC driver was written, but the heavy weight OS did not perform as well as the Cougar lightweight kernel on many benchmarks. References X86 supercomputers Intel Sandia National Laboratories 32-bit computers