LiveStack: OS Support for Cluster-Scale Full-Stack Live Simulation

Cluster-scale full-stack simulation is essential for evaluating distributed software stacks and emerging hardware components before deployment. Such simulation must achieve both full-stack fidelity for the unmodified production stack and the simulation performance required for iterative configuration exploration. However, no existing method achieves both. We present LiveStack, an OS-level approach to cluster-scale full-stack simulation built on top of the Linux virtualization stack. LiveStack comprises four subsystems: simulation-oriented scheduling, live memory hierarchy management, simulation-aware IPC, and distributed simulation orchestration. Together, they coordinate live and modeled components under shared simulated time while controlling interference among co-located live hosts. These mechanisms point toward simulation-native OS support, where simulation control and orchestration become core OS responsibilities.