Abstract
Flash memory is being rapidly deployed as data storage for mobile devices such as PDAs, MP3 players, mobile phones, and digital cameras, mainly because of its low electronic power, nonvolatile storage, high performance, physical stability, and portability. One disadvantage of flash memory is that prewritten data cannot be dynamically overwritten. Before overwriting prewritten data, a time-consuming erase operation on the used blocks must precede, which significantly degrades the overall write performance of flash memory. In order to solve this “erase-before-write” problem, the flash memory controller can be integrated with a software module, called “flash translation layer (FTL).” Among many FTL schemes available, the log block buffer scheme is considered to be optimum. With this scheme, a small number of log blocks, a kind of write buffer, can improve the performance of write operations by reducing the number of erase operations. However, this scheme can suffer from low space utilization of log blocks. In this paper, we show that there is much room for performance improvement in the log buffer block scheme, and propose an enhanced log block buffer scheme, called FAST (full associative sector translation). Our FAST scheme improves the space utilization of log blocks using fully-associative sector translations for the log block sectors. We also show empirically that our FAST scheme outperforms the pure log block buffer scheme.
- Ban, A. 1995. Flash file system. United States Patent, No. 5,404,485, April.Google Scholar
- Chung, T. S., Park, D. J., Park, S. W., Lee, D. H., Lee, S. W., and Song, H. J. 2006. System software for flash memory: a survey. In Proceedings of the 2006 IFIP International Conference on Embedded And Ubiquitous Computing (EUC 2006). (Aug.) Seoul, Korea. Google ScholarDigital Library
- Douglis, F., Caceres, R., Kaashoek, M. F., Li, K., Marsh, B., and Tauber, J. A. 1994. Storage alternatives for mobile computers. In Proceedings of the 1st Symposium on Operation Systems Design and Implementation (OSDI), Monterey, CA, November 1994, J. Lepreau, Eds. Usenix Association, Berkeley, CA. 25--37. Google ScholarDigital Library
- Estakhri, P. and Iman, B. 1999. Moving sequential sectors within a block of information in a flash memory mass storage architecture, United States Patent, No. 5,930,815, July.Google Scholar
- Gal, E. and Toledo, S. 2005. Algorithms and data structures for flash memories. ACM Computing Surveys 37, 138--163. Google ScholarDigital Library
- Hennessy, J. L. and Patterson, D. A. 2003. Computer Architecture: A Quantitative Approach, 3rd ed. Morgan Kaufmann, San Mateo, CA. Google ScholarDigital Library
- Kim, B. S. and Lee, G. Y. 2002. Method of driving remapping in flash memory and flash memory architecture suitable therefore, United States Patent, No. 6,381,176, April.Google Scholar
- Kim, J. S., Kim, J. M., Noh, S. H., Min, S. L., and Cho, Y. K. 2002. A space-efficient flash translation layer for compactflash systems. IEEE Transactions on Consumer Electronics 48, 366--375. Google ScholarDigital Library
- Lawton, G. 2006. Improved flash memory grows in popularity. IEEE Computer 39, 1 (Jan.), 16--18. Google ScholarDigital Library
- Paulson, L. D. 2005. Will hard drivers finally stop shrinking? IEEE Computer 38, 5 (May), 14--16. Google ScholarDigital Library
- Samsung Electronics. 2005. Nand flash memory & smartmedia data book.Google Scholar
- Shinohara, T. 1999. Flash memory card with block memory address arrangement. United States Patent, No. 5,905,993, May.Google Scholar
Index Terms
- A log buffer-based flash translation layer using fully-associative sector translation
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