Profiling the Operational Behavior of OS Device Drivers

As the complexity of modern Operating Systems (OS) increases, testing key OS components such as device drivers(DD) becomes increasingly complex given the multitude of possible DD interactions. If representative operational activity profiles of DDs within an OS could be obtained, these could significantly improve the understanding of the actual operational DD state space towards guiding the test efforts. Focusing on characterizing DD operational activities, this paper proposes a quantitative technique for profiling the runtime behavior of DDs using a set of occurrence and temporal metrics obtained via I/O traffic characterization. Such profiles are used to improve test adequacy against real-world workloads by enabling similarity quantification across them. The profiles also reveal execution hotspots in terms of DD functionalities activated in the field, thus allowing for dedicated test campaigns. A case study on actual Windows drivers substantiates our proposed approach.