12.7. Conclusion

This chapter has presented a systematic process for robustness evaluation of operating systems. Robustness is the ability of a system to withstand external perturbations arising in its environment. The key steps involved in evaluating the robustness of an OS are:

• Definition objectives and goals.

• Definition system model and the target of a study.

• Definition of fault models and workload.

• Definition of the robustness metrics.

A case study shows how each of the steps can be implemented for a real OS, and the last section shows that the results from such a study are very useful for comparing system components, in this case, device drivers.