A Dynamic Replica Factor Calculator for Weighted Dynamic Replication Management in Cloud Storage Systems

摘要

Data replication is a widely-used technique in cloud storage systems to ensure availability of data. In static replication policies, the number of replicas to be created is decided statically at the time of cloud system setup. The replication of data needs to be dynamic considering changing pattern in user request and storage capacity. This will ensure that storage space is not wasted by keeping unnecessary replicas for least used data. In this work, a strategy is proposed to dynamically set the replica factor for each data item considering the popularity of data, its current replication factor and the number of active nodes present in the cloud storage. The proposed strategy is implemented in Hadoop Distributed File System (HDFS) and the experimental results shows that proposed method maintains an optimal number of replicas for each data item based on its popularity, without compromising on the availability constraint of cloud storage.