Design And Implementation Of Android Cloud Storage File System

In today's society,cloud storage technology has been developing vigorously,and has been widely applied in different fields around us.How to effectively use cloud storage technology on mobile devices has become the current concern.Most of the cloud storage mobile clients on the market are based on application layer development,which makes the cloud storage data access only through the software corresponding to the cloud client,and it is difficult to obtain cloud storage data between different applications.Moreover,the application layer based cloud storage method is decoupled from the operating system,and can not organize and manage data at the level of the file system.At the same time,the storage capacity of mobile terminals is limited,so the massive data stored in cloud storage is limited to the limited storage of mobile phones,so we need to deal with cold and hot data in a reasonable way.To solve these problems,we design and implement the Android cloud storage file system ACFS.The basic work is as follows:This paper designs a user space file system based on FUSE development and implements multiple file system calls,including creating and deleting directories,creating and deleting files,reading and writing files,and so on.ACFS chooses object storage as cloud back end,and user operation local file system is actually manipulate object storage on the back side of cloud.The two level caching model is designed and implemented to maintain the cold and hot data of the client's local system.The hot data of the client file system is maintained by the memory cache based on the LRU replacement algorithm,and the cold data of the client file system is saved by the disk cache composed of the SQLite database and the SD card.ACFS is a file system running under the Android operating system and can be mounted on a Android arbitrarily writable directory,with good compatibility and compatible with more than Android 2.3 versions.At present,ACFS has completed the development.This paper tests its file system function,performance,caching efficiency and compatibility,and analyzes the actual case.According to the test results and test cases,it shows that the system runs stably and can be applied to practice.