Centre for Distributed Systems and Software Engineering, Monash University, 900 Dandenong Road, Caulfield East, Melbourne, VIC, Australia;Oak Ridge National Laboratory, Computational Sciences and Engineering Division, 900 Dandenong Road, Caulfield East, Oak Ridge, TN, Australia;Oak Ridge National Laboratory, Computational Sciences and Engineering Division, 900 Dandenong Road, Caulfield East, Oak Ridge, TN, Australia;Faculty of Economics, LIAAD-INESC Porto, University of Porto, L.A. Rua de Ceuta, 118, 6, Porto, TN, Portugal;Computer Science and Engineering Department, University of Notre Dame, 353 Fitzpatrick Hall, Notre Dame, IN, Portugal