TOSS (operating system)

The Tri-Lab Operating System Stack (TOSS) is a Linux distribution based on Red Hat Enterprise Linux (RHEL) that was created to provide a software stack^[1] for high performance computing (HPC) clusters^[2] for laboratories within the National Nuclear Security Administration (NNSA).^[3] The operating system allows multiple smaller systems to emulate a high-performance computing (HPC) platform.^[1]

Tri-Lab Operating System Stack

OS family	Unix-like
Working state	Current
Package manager	RPM Package Manager[1]

Linux distribution

The name "tri-lab" refers to the three major NNSA labs, the Lawrence Livermore National Laboratory, the Los Alamos National Laboratory, and the Sandia National Laboratories.^[4]

The OS is used by NNSA computers including the El Capitan supercomputer^[5] and systems using ARM architecture including the ThunderX2 system on a chip (SoC).^[6] In addition to being used by the National Nuclear Security Administration (NNSA),^[2] most of the systems in NASA's High-End Computing Capability Project, part of the NASA Advanced Supercomputing Division, were all migrated to TOSS in March 2022.^[7]

Many of the software packages included in TOSS are from the RHEL repository. Additional packages are built using Fedora's Koji build system to create RPM packages.^[1] The system also uses SLURM and Flux scheduling and resource management software.^[1]