Online Scheduling to Maximize Resource Utilization of Deadline-Constrained Workflows on the Cloud

In this paper, we assume workflows under deadline constraints are submitted to the cloud from time to time. Every time a workflow is submitted, the cloud needs to determine whether it can agree with the specific constraint set by the user. If the cloud agrees to admit the workflow, cloud resources can be allocated for its execution in a way the deadline constraint can be met, while the existing load in the underlying resources is considered. The focus of this paper is how to schedule the tasks of each admitted workflow so that the resource utilization can be maximized. A variety of online scheduling algorithms have been proposed and evaluated using a simulator that manages to generate a stream of workflows for which an optimal schedule, with 100% resource utilization and without deadline violation, is guaranteed to exist.