Bicriteria Service Scheduling with Dynamic Instantiation for Workflow Execution on Grids

Nowadays the grid is turning into a service-oriented environment. In this context, there exist solutions to the execution of workflows and most of them are web-service based. Additionally, services are considered to exist on a fixed host, limiting the resource alternatives when scheduling the workflow tasks. In this paper we address the problem of dynamic instantiation of grid services to schedule workflow applications. We propose an algorithm to select the best resources available to execute each task of the workflow on the already instantiated services or on services dynamically instantiated when necessary. The algorithm relies on the existence of a grid infrastructure which could provide dynamic service instantiation. Simulation results show that the scheduling algorithm associated with the dynamic service instantiation can bring more efficient workflow execution on the grid.