Timed Perturbation Analysis: An Approach for Non-Intrusive Monitoring of Real-Time Computations

A task which is a part of a real time application must not only perform a specific function but it must also execute under timing constraints specified in the form of deadlines by which the output results must be computed. Thus, any attempt to monitor the run-time behavior of a real time task through code instrumentation can potentially alter the program's timing behavior. In this paper we develop perturbation analysis techniques to identify the situations in which the run-time monitoring activities can be performed non-intrusively. The techniques identify the idle time available during the execution of a task and schedule the monitoring task during these times. Instead of treating a monitoring task as an indivisible unit, we partition the monitoring work among various points at which idle time is available. Keywords - monitoring, tracing, instrumentation, perturbation analysis, asynchronous communication. 1 Introduction Due to the complexity of both sequential and distribute..