Performance analysis of real-time software supporting fault-tolerant operation

Analyzing the performance of real-time control systems featuring mechanisms for online recovery from software faults is discussed. The application is assumed to consist of a number of interacting cyclic processes. The underlying hardware is assumed to be a multiprocessor, possibly with a separate control processor. The software structure is assumed to use design diversity along with forward and/or backward recovery. A detailed but efficiently solvable model for predicting various performance and reliability characteristics is developed. One of the key ideas used in modeling is hierarchical decomposition, which enables computation of level-oriented performance parameters in an efficient manner. The model is general, and adaptable for a number of useful special cases