Modeling the Propagation of Intermittent Hardware Faults in Programs

Intermittent hardware faults are bursts of errors that last from a few CPU cycles to a few seconds. Recent studies have shown that intermittent fault rates are increasing due to technology scaling and are likely to be a significant concern in future systems. We study the impact of intermittent hardware faults in programs. A simulation-based fault-injection campaign shows that the majority of the intermittent faults lead to program crashes. We build a crash model and a program model that represents the data dependencies in a fault-free execution of the program. We then use this model to glean information about when the program crashes and the extent of fault propagation. Empirical validation of our model using fault-injection experiment shows that it predicts almost all actual crash-causing intermittent faults, and in 93% of the considered faults the prediction is accurate within 100 instructions. Further, the model is found to be more than two orders of magnitude faster than equivalent fault-injection experiments performed with a microprocessor simulator.