Work-in-Progress: Isochronous Execution Models for Mixed-Criticality Systems on Parallel Processors

We propose redundancy-based execution models to address the reliability and correctness of safety/time-critical applications, and in particular, mixed-criticality systems. In our models, every job has one or more (possibly identical) versions, and all versions of a job are to run isochronously on multiple parallel machines in a lockstep fashion. The redundant machines act as monitoring coprocessors, and the execution of a job is deemed successful as soon as one of its versions completes within its worst-case execution time estimate, at which point we may terminate all the other versions. Doing so e ectively increases the chance that a job completes successfully and thus provides timing guarantees in the form of increased predictability. We present several allocation and scheduling problems with varying levels of generality, with the objective of minimizing the maximum makespan across all processors.