A Flash File System to Support Fast Mounting for NAND Flash Memory Based Embedded Systems
In embedded systems, NAND flash memory is typically used as a storage medium because of its non-volatility, fast access time and solid-state shock resistance. However, it suffers from out-place-update, limited erase cycles and page based read/write operations. Flash file systems such as JFFS2 and YAFFS, allocate memory spaces using LFS (Log-structured File System) to solve these problems. Because of this, many pieces of a file are scattered through out flash memory. Therefore, these file systems should scan entire flash memory to construct the data structures during the mounting. This means that it takes a long time to mount such file systems on a large chip. In this paper, we design and propose a new flash memory file system which targets mobile devices that require fast mounting. We experimented on the file system performance and the results show that we improve the mounting time by 64%–76% as flash usage compared to YAFFS.
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- 1.Bird, T.R.: Methods to Improve Bootup Time in Linux. In: Proc. of the Ottawa Linux Symposium (OLS), Sony Electronics (2004)Google Scholar
- 2.Two Technologies Compared: NOR vs. NAND, www.m-sys.com/NR/rdonlyres/24795A9E-16F9-404A-857C-C1DE21986D28/229/NOR_vs_NAND5.pdf
- 3.Chang, M.L., Lee, P.C.H., Chang, R.C.: Managing Flash Memory in Personal Communication Devices. In: Proc. of IEEE Symp. on Consumer Electronics (1997), Berlin, pp. 177–182 (1996)Google Scholar
- 4.Chiang, M.-L., Lee, P.C.H., Chang, R.-C.: Cleaning Policies in Mobile Computers Using Flash Memory. Journal of System and Software ibr 1, 108–121 (1997)Google Scholar
- 5.Woodhouse, D.: JFFS: The Journaling Flash File System. Technical Paper of RedHat inc. (2001)Google Scholar
- 6.YAFFS Spec., http://www.aleph1.co.uk/yaffs/yaffs.html
- 8.Samsung Electronics: Advantages of SLC NAND Flash Memory, http://www.samsungelectronics.com/
- 9.Flash Filesystems for Embedded Linux Systems, http://linuxjournal.com/node/4678/
- 10.JFFS3 Design Issue, http://www.linux-mtd.infradead.org/tech/JFFS3design/
- 12.Understanding the Flash Translation Layer(FTL) specification. Intel (1997)Google Scholar
- 13.Irlam, G.: Unix File Size Survey, http://www.base.com/gordoni/gordoni.html