Network conscious design of distributed real-time systems

Abstract

In this paper, we present a network conscious approach to designing distributed real-time systems. Given a task graph design of the system, the end-to-end constraints on the inputs and outputs, and the task allocation on a given distributed platform, we automatically generate task attributes (e.g., periods and deadlines) such that (i) the task set is schedulable, and (ii) the end-to-end constraints are satisfied. The method works by first transforming the end-to-end constraints into a set of intermediate constraints on task attributes, and then solving the intermediate constraints. The complexity of constraint solving is tackled by reducing the problem into more tractable parts, and then solving each subproblem using heuristics to enhance schedulability. The methodology presented in this process can be mostly automated, and provides useful feedback to a designer when it fails to find a solution. We expect that the techniques presented in this paper will help reduce the laborious process of designing a real-time system, by bringing resource contention and schedulability aspects early into the design process.