PROBABILISTIC EVALUATION OF ONLINE CHECKS IN FAULT-TOLERANT MULTIPROCESSOR SYSTEMS

The analysis of fault-tolerant multiprocessor systems that use concurrent error detection (CED) schemes is much more difficult than the analysis of conventional fault-tolerant architectures. Various analytical techniques have been proposed to evaluate CED schemes deterministically. However, these approaches are based on worst-case assumptions related to the failure of system components. Often, the evaluation results do not reflect the actual fault tolerance capabilities of the system. In this paper, we develop a probabilistic approach to evaluate the fault detecting and locating capabilities of on-line checks in a system. The various probabilities associated with the checking schemes are identified and used in the framework of the matrix-based model [1]. Based on these probabilistic matrices, estimates for the fault tolerance capabilities of various systems are derived analytically.