A Fault Tolerant Task Scheduling Method for Optimal use of Resources in Cloud Computing Environment

In recent years, cloud computing is becoming eminent in the field of information technology. In a cloud computing environment, there is a potential for faults. There are different methods for dealing with faults, but with regard to the features and characteristics of the cloud computing environment, the use of fault tolerance methods is the best choice for this environment.One of the biggest issues in fault tolerance methods is the efficient use of resources. The optimal use of resources is important for cloud providers and customers. Unfortunately, the optimal use of resources in fault tolerance methods has not been much considered by researchers and cloud service providers. In this paper taking into account the dependence between tasks, an attempt has been made to provide a fault tolerance method on virtual machines, which in addition to being tolerant of fault, achieves optimum use of resources. In this method, by using a priority scheduler, each task is assigned a priority, then tasks are sent by the order of priority to their virtual  machines for processing. The results of simulation by the cloudsim simulator show that the proposed method has been able to improve the use of resources more than other methods and with 95% confidence intervals it has achieved (29.15% and 22.74%) improvement in the number of processors, (30.76% and 22.34%) improvement in memory usage and (29.71% and 22.88%) improvement in the use of bandwidth.