DOI: 10.2298/CSIS120712021M EasyFJP: Providing Hybrid Parallelism as a Concern for Divide and Conquer Java Applications

Abstract. Because of the increasing availability of multi-core machines, clusters, Grids, and combinations of these there is now plenty of compu-tational power, but today’s programmers are not fully prepared to exploit parallelism. In particular, Java has helped in handling the heterogeneity of such environments. However, there is a lot of ground to cover regard-ing facilities to easily and elegantly parallelizing applications. One path to this end seems to be the synthesis of semi-automatic parallelism and Parallelism as a Concern (PaaC). The former allows users to be mostly unaware of parallel exploitation problems and at the same time manually optimize parallelized applications whenever necessary, while the latter al-lows applications to be separated from parallel-related code. In this pa-per, we present EasyFJP, an approach that implicitly exploits parallelism in Java applications based on the concept of fork-join synchronization pat-tern, a simple but effective abstraction for creating and coordinating paral-lel tasks. In addition, EasyFJP lets users to explicitly optimize applications through policies, or user-provided rules to dynamically regulate task gran-ularity. Finally, EasyFJP relies on PaaC by means of source code gener-ation techniques to wire applications and parallel-specific code together. Experiments with real-world applications on an emulated Grid and a clus-ter evidence that EasyFJP delivers competitive performance compared to state-of-the-art Java parallel programming tools