Scattering and Placing Data Replicas to Enhance Long-Term Durability

Distributed storage systems have to ensure data availability and durability despite the occurrence of failures. To do so, many of them rely on replication mechanisms. We show that the layout of the data block copies on the nodes, chiefly the way the copies are scattered, has a major impact on the reparation speed and thus on the data loss ratio. In this paper, we propose an approach that provides the ability: (i) to finely tune the proportion of common content stored by the nodes, and (ii) to control the storage load distribution while creating new data block copies. We propose a simulation model that allows us to present a long-term study of the impact of the data block copies layout and the system's storage load on the data loss ratio.