Fault injection in the process descriptor of a Unix-based operating system

Transient faults in computer-based systems for which high availability is a strict requirement, originated from several sources, like high energy particles, are a major issue. Fault injection is a commonly used method to evaluate the sensitivity of such systems. The paper presents an evaluation of the effects of faults in the memory containing the process descriptor of a Unix-based Operating System. In particular the state field has been taken into consideration as the main target, changing the current state value into another one that could be valid or invalid. An experimental analysis has been conducted on a large set of different tasks, belonging to the operating system itself. Results of tests show that the state field in the process descriptor represents a critical variable as far as dependability is considered.