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An operating system course draws from a well-defined fundamental theory, but one needs to consider how more re- cent advances, not necessarily in the theory itself, can be applied to improve the course and the general body of knowledge of the student. The goal of this paper is to show how recent software engineering developments can be introduced to such a course to not only satisfy the theory requirements, but also make the theory more understandable. In particular, this paper focuses on how students can effectively learn the Unified Modeling Language, the object-oriented methodology, and the Java programming language in the context of an operating systems course. The goal is to form a systematic software engineering process for operating system design and implementation. [ABSTRACT FROM AUTHOR]

For the development of communications software com- posed of many modules, protocol validation is essential to detect errors in the interactions among the modules. A number of protocol validation techniques were proposed in the past, but the validation time required by these techniques is too long for many actual protocols. This paper proposes a new fast protocol validation technique to overcome this drawback. The proposed technique is to construct the minimum acyclic form of state transitions in individual processes of the protocol, and to detect protocol errors such as system deadlocks and channel overflows fast. This paper also presents a protocol validation system based on the proposed technique to confirm its feasibility and shows validation results for some actual protocols obtained with this system. As a result, the protocol validation system is expected to contribute to a great extent to the improvement of the productivity in development and maintenance of communications software. [ABSTRACT FROM AUTHOR]

Many modern software systems are designed to be highly configurable so they can run on and be optimized for a wide variety of platforms and usage scenarios. Testing such systems is difficult because, in effect, you are testing a multitude of systems, not just one. Moreover, bugs can and do appear in some configurations, but not in others. Our research focuses on a subset of these bugs that are "option-related"--those that manifest with high probability only when specific configuration options take on specific settings. Our goal is not only to detect these bugs, but also to automatically characterize the configuration subspaces (i.e., the options and their settings) in which they manifest. To improve efficiency, our process tests only a sample of the configuration space, which we obtain from mathematical objects called covering arrays. This paper compares two different kinds of covering arrays for this purpose and assesses the effect of sampling strategy on fault characterization accuracy. Our results strongly suggest that sampling via covering arrays allows us to characterize option-related failures nearly as well as if we had tested exhaustively, but at a much lower cost. We also provide guidelines for using our approach in practice. [ABSTRACT FROM AUTHOR]

In order to effectively optimize complex programs built in a layered or recursive fashion (possibly from reused general components), the programmer has a critical need for performance information connected directly to the design decisions and other optimization opportunities present in the code. Call path refinement profiles are novel tools for guiding the optimization of such programs, that: 1) provide detailed performance information about arbitrarily nested (direct or indirect) function call sequences, and 2) focus the user's attention on performance bottlenecks by limiting and aggregating the information presented. This paper discusses the motivation for such profiles, describes in detail their implementation in the CPPROF profiler, and relates them to previous profilers, showing how most widely available profilers can be expressed simply and efficiently in terms of call path refinements. [ABSTRACT FROM AUTHOR]

The formalism of temporal logic has been suggested to be an appropriate tool for expressing the semantics of concurrent programs. This paper is concerned with the application of temporal logic to the specification of factors affecting the synchronization of concurrent processes. Towards this end, we first introduce a model for synchronization and axiomatize its behavior. SYSL, a very high-level language for specifying synchronization properties, is then described. It is designed using the primitives of temporal logic and features constructs to express properties that affect synchronization in a fairly natural and modular fashion. Since the statements in the language have intuitive interpretations, specifications are humanly readable. In addition, since they possess appropriate formal semantics, unambiguous specifications result. [ABSTRACT FROM AUTHOR]