An Application-Based Adaptive Replica Consistency for Cloud Storage

The intrinsic characteristic heterogeneous of cloud applications makes their consistency requirements different. Furthermore, the consistency requirement of certain application changes continuously at runtime, so a fixed consistency strategy is not enough. An application-based adaptive mechanism of replica consistency is proposed in this paper. We divide the consistency of applications into four categories according to their read frequencies and update frequencies, and then design corresponding consistency strategies. Applications select the most suitable strategy automatically at runtime to achieve a dynamic balance between consistency, availability, and performance. Evaluation results show that the proposed mechanism decreases the amount of operations significantly while guaranteeing the application´s consistency requirement.