MLFS: A multiple layers share file system for cloud computing

Cloud computing systems offer computing and storage resources at a low price. The users only pay for it when the VM(short for Virtual Machine) is running. While after VMs shut down, the vendors also need disk space to store multi-gigabyte VM images. Past studies use deduplication to reduce the space requirements, but it needs to calculate hash values of each block and store them. It also causes performance overhead costs to find identical content. In this paper, We propose a multiple layers file sharing system(MLFS) designed for cloud computing. It stores OS data, Application data, and user data in different layers. Multiple users share OS data layers. Application data are constructed according to users' selection, and they are deleted after VM shut down. We compare our solution with ordinary storage systems, storage systems with deduplication, the results show that MLFS can save more space than others, while achieving reasonable performance in file system I/O operating.