With emerging "pay-as-you-go object storage" services, file system backup to object storage is an attractive option in terms of total cost of ownership. However, if a failure or a disaster occurs, a conventional backup system with object storage requires a long time to recover the necessary data since it must restore the entire directory structure of the file system from object storage before accessing the data. In this paper, "directory-aware backup" (DAB), which achieves on-demand restore as part of file system backup to object storage, is proposed. On-demand restore is a function that restores only a certain directory or file according to the request from an end user. The proposed method backs up relationships between a file and an object on a directory basis in order to efficiently handle the relationships in the restore. It is experimentally shown that the proposed method reduces the response time of file access involving restore by over an order of magnitude.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.