Execution-time clocks and Ravenscar kernels

Abstract

The kind of high-integrity real-time systems to which the Ada Ravenscar profile is targeted often require overrun detection for enhanced reliability in the time domain Execution-time clocks and timers have been proposed to fulfill this need, but only programming patterns based on asynchronous transfer of control, and thus incompatible with the profile, have been provided up to now. In this paper an assessment of the compatibility of the proposed execution-time mechanisms with the Ravenscar profile is made, and some programming patters for using them are proposed. The patterns are intended to provide basic overrun detection and handling capabilities to high-integrity real-time systems.