Efficient parallel edge-centric approach for relaxed graph pattern matching

Prior algorithms on graph simulation for distributed graphs are not scalable enough as they exhibit heavy message passing. Moreover, they are dependent on the graph partitioning quality that can be a bottleneck due to the natural skew present in real-world data. As a result, their degree of parallelism becomes limited. In this paper, we propose an efficient parallel edge-centric approach for distributed graph pattern matching. We design a novel distributed data structure called ST that allows a fine-grain parallelism, and hence guarantees linear scalability. Based on ST, we develop a parallel graph simulation algorithm called PGSim. Furthermore, we propose PDSim, an edge-centric algorithm that efficiently evaluates dual simulation in parallel. PDSim combines ST and PGSim in a Split-and-Combine approach to accelerate the computation stages. We prove the effectiveness and efficiency of these propositions through theoretical guarantees and extensive experiments on massive graphs. The achieved results confirm that our approach outperforms existing algorithms by more than an order of magnitude.

     

On performance evaluation and design of atomic commit protocols for mobile transactions

The challenges of wireless and mobile computing environments have attracted the attention of researchers to revisit the conventional transaction paradigm. Indeed, this paradigm is an indispensable asset in modern information systems. The atomicity property of a distributed transaction is ensured with the use of an atomic commit protocol (ACP). Due to their great importance for transaction systems, the recent advances in mobile computing development have renewed the interest in the design of ACPs for mobile systems. The work presented in this paper studies the impact of the various and fluctuant parameters of wireless and mobile systems on a set of ACPs for mobile environment. It highlights performance indices which give orientations to the design of an adaptable approach that supports different atomicity notions satisfying a wide range of applications and environment requirements.