A new online scheduling approach for enhancing QOS in cloud

Abstract

Quality-of-Services (QoS) is one of the most important requirements of cloud users. So, cloud providers continuously try to enhance cloud management tools to guarantee the required QoS and provide users the services with high quality. One of the most important management tools which play a vital role in enhancing QoS is scheduling. Scheduling is the process of assigning users’ tasks into available Virtual Machines (VMs). This paper presents a new task scheduling approach, called Online Potential Finish Time (OPFT), to enhance the cloud data-center broker, which is responsible for the scheduling process, and solve the QoS issue. The main idea of the new approach is inspired from the idea of passing vehicles through the highways. Whenever the width of the road increases, the number of passing vehicles increases. We apply this idea to assign different users’ tasks into the available VMs. The number of tasks that are allocated to a VM is in proportion to the processing power of this VM. Whenever the VM capacity increases, the number of tasks that are assigned into this VM increases. The proposed OPFT approach is evaluated using the CloudSim simulator considering real tasks and real cost model. The experimental results indicate that the proposed OPFT algorithm is more efficient than the FCFS, RR, Min-Min, and MCT algorithms in terms of schedule length, cost, balance degree, response time and resource utilization.