Middleware and multicore architecture: Challenges and potential enhancements from software engineering perspective

An empirical study that examines challenges middleware software systems have to take full advantages of multicore technology is presented. The study is conducted on 9 open source middleware systems containing over 3.39 million lines of code. Each system is analyzed and the inhibitors to parallelization are detected and presented. Additionally, some challenges in analyzing, adapting, and re-engineering middleware systems to better utilize modern multi-core architectures are determined including function side effects. Function side effects categorized based on their types and the complexity they pose in conducting inter-procedural static analysis. The data shows that the most prevalent inhibitor by far is functions called within for-loops that have side effects. Moreover, the study shows that parameters by reference and global variables modification are the most prevalent side effects that poses the greatest challenges in re-engineering middleware systems to improve their parallelizability to better utilize multi-core architectures. That is, conducting accurate program analysis with existing software engineering tools becomes exigent and impractical with those side effects. The study suggests some software engineering techniques (e.g., refactoring) that have the potential to improve the parallelizability of middleware systems.