The Rearch Of Embedded File System KTFS Based On CAR Component

Embedded file system becoms more and more important,because many data resources should be managed in embedded applications along with the development of embedded technology.The difference between normal file system and embedded file system is that design of the latter should not only satisfy the various requests for data storage but also reduce the negative effect to entire system.The negative effect mainly expresses at the aspects of real-time response,portability and configurability.KTFS is embedded file system based on the elastos "agile" core technology,using FAT as storage structure and flash as storage equipment and implementing in CAR component.In this paper,we first research the relevant theoretical knowledge of the KTFS,then analyse the advantage and disadvantage of the component file system and set up the theoretical model and architecture,dividing the file system into four levels:flash block device driver,cache management, file system kernel and file system interface layer.KTFS can be dynamically loaded into the kernel or user state for system stability and efficiency through using the elastos "agile" core technology whereas traditional file system can only be loaded into the kernel or user state.In the meantime,abstract and implement file system interface according to the principle of interface design.Finally,results validate the completion and reliability of interface set according to the testing on functionality and performance after KTFS is attached to the elastos system.The main research achievements are sumarrized as follows:1.Demonstrate feasibility and necessity of component file system, and point out the key problem to solve;2.Design and implement the interface set of KTFS based on the principle of design at elastos;3.Improve LRU block replacement algorithm of the file system cache through using the combination of hash table and LRU list to enhance the efficiency of LRU;...