Editing ASCI Red (section)

== Operating system ==

The different partitions of ASCI Red run on different [[operating system]]s. 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|Intel Paragon XP/S]] Supercomputer.<ref name=Sandia/> ASCI Red's Compute partition runs on an [[operating system]] named Cougar.<ref name="Brightwell"/> Cougar is a Sandia Labs and University of New Mexico collaboration; it is a [[lightweight kernel operating system|lightweight OS]] based on PUMA and [[SUNMOS]], two systems that were also designed for use on the Paragon supercomputer.<ref name="Brightwell"/> 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.<ref name=Brightwell />