1. National Engineering Research Center for Big Data Technology and System, Services Computing Technology and System Laboratory and the Cluster and Grid Computing Laboratory, School of Computer Science and Technology, Huazhong University of Science and Technology, Wuhan, China
2. School of Electronic Information and Communications, Huazhong University of Science and Technology, Wuhan, China
3. College of Computer Science and Software Engineering, Shenzhen University, Shenzhen, China
4. Department of Computer Science and Software Engineering, Shenzhen University, 3688 Nanhai Avenue, Shenzhen, P.R. China