Earliest Deadline Message Scheduling with Limited Priority Inversion

This paper presents an innovative approach for scheduling network messages with real-time dynamic algorithms. The solution described in this work takes advantage of the increased network utilization allowed by dynamic scheduling methods and bounds at the same time the priority invertion phenomena caused by the lack of a sufficient number of priority levels. We give a very simple formula for checking the schedulability of a set of real-time packetized messages, and we show that the penalty introduced by priority inversion can be bounded within a satisfactory predictable range. 1 Introduction It is commonly believed that distribution is a natural choice for most real-time systems, due to the advantages in robustness, cost, and the physical characteristics of most control architectures, where sensors and actuators are distributed in plants or large machines (for example aircrafts) and connected to a number of cooperating computers. Only in very recent times the need for predictable compu..