Software Implemented Fault Insertion: An FTMP Example.

Abstract : This report presents a model for fault insertion through software, describes its implementation on a fault tolerant computer, FTMP, presents a summary of fault detection, identifications, and reconfiguration data collected with software implemented fault insertion and compares the results to hardware fault insertion data. The software fault insertion model assumes faults manifest to data errors at the output of a task. The implementation of the software fault insertion model on FTMP allows inserted faults to emulate faults in the processor data path, processor control path, system memory, and system transmit bus. The experimental results showed detection time there was no correlation between software inserted faults, and hardware inserted faults; this is because hardware inserted faults must manifest to errors before detection, whereas software inserted faults immediately exercise the error detection mechanisms. In summary, although software fault insertion does not map directly to hardware fault insertion, experiments indicate software fault insertion as a means to characterize the fault handling capabilities of a system in error detection, identification, and error recovery. Keywords: Debugging(Computers); Computer program reliability; Computer aided diagnosis.