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Research of the file system of volume holographic storage based on virtual storage layer

Volume holographic storage (VHS) is currently the subject of widespread interest as a fast-readout-rate, high-capacity digital data-storage technology. To make need of characteristics of the VHS, the paper present the file system using a virtual storage layer (VSL) which can be compatible with the logic layer of the current used file system and accommodate the requirement of VHS in the physical layer. The VSL which is made of the super block, directory area, the metadata area and dynamic file area can connect directly to the storage media one side and implement compatible to the existing file system by providing the operating interfaces for the above logical file system. We produce the two layer storage structure which effectively reduces the number of disk accessed and improves the speed of file read and write. The allocation mode of 'hybrid of block and zone' and allocation strategy of 'block priority' greatly improve the space utilization rate of storage device and enforce the storage adaptability in VHS.