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Preventing Fast Wear-out of Flash Cache with An Admission Control Policy

  • Received : 2015.04.22
  • Accepted : 2015.06.08
  • Published : 2015.10.30

Abstract

Recently, flash cache is widely adopted as the performance accelerator of legacy storage systems. Unlike other cache media, flash cache should be carefully managed as it has peculiar characteristics such as long write latency and limited P/E cycles. In particular, we make two prominent observations that can be utilized in managing flash cache. First, a serious worn-out problem happens when the working-set of a system is beyond the capacity of flash cache due to excessively frequent cache replacement. Second, more than 50% of data has no hit in flash cache as it is a second level cache. Based on these observations, we propose a cache admission control policy that does not cache data when it is first accessed, and inserts it into the cache only after its second access occurs within a certain time window. This allows the filtering of data disruptive to flash cache in terms of endurance and performance. With this policy, we prolong the lifetime of flash cache 2.3 times without any performance degradations.

Keywords

References

  1. Faloutsos, C., Ng, R., & Sellis, T., Flexible and adaptable buffer management techniques for database management systems, IEEE Transactions on Computers, vol. 44, no. 4, pp. 546-560, 1995. https://doi.org/10.1109/12.376169
  2. Johnson, T. & Shasha, D. 2Q: a low overhead high performance buffer management replacement algorithm. In Proceedings of the 20th International Conference on Very Large Data Bases (VLDB), pp. 439-450, 1994.
  3. O'Neil, E.J., O'Neil, P.E., & Weikum, G. The LRU-K page replacement algorithm for database disk buffering. In Proceedings of ACM SIGMOD International Conference on Management of Data, pp. 297-306, 1993,.
  4. Kim, J.M., Choi, J., Kim, J., Noh, S.H., Min, S.L., Cho, Y., & Kim, C.S. A low-overhead, highperformance unified buffer management scheme that exploits sequential and looping references, In Proceedings of USENIX Symposium on Operating System Design and Implementation (OSDI), pp. 119-134, 2000.
  5. Lee, D., Choi, J., Kim, J.H., Noh, S.H., Min, S.L., Cho, Y., & Kim, C.S. LRFU: a spectrum of policies that subsumes the least recently used and least frequently used policies. IEEE Transactions on Computers, vol. 50, no. 12, pp. 1352-1361, 2001. https://doi.org/10.1109/TC.2001.970573
  6. Jiang, S. & Zhang, X. Making LRU friendly to weak locality workloads: a novel replacement algorithm to improve buffer cache performance. IEEE Transactions on Computers, vol. 5, no. 8, pp. 939-952, 2005.
  7. Leventhal, A. Flash Storage Memory. Communications of the ACM, vol. 51, no. 7, pp. 47-51, 2008. https://doi.org/10.1145/1364782.1364796
  8. Megiddo, N. & ModhaHA, D.S. ARC: a self-tuning, low overhead replacement cache. In Proceedings of the 2nd USENIX Conference on File and Storage Technologies, pp. 115-130, 2003.
  9. Jiang, S. & Zhang, X. Making LRU friendly to weak locality workloads: a novel replacement algorithm to improve buffer cache performance. IEEE Transactions on Computers, vol. 5, no. 8, pp. 939-952, 2005.
  10. Park, S., Jung, D., Kang, J., Kim, J., & Lee, J. CFLRU: replacement algorithm for flash memory. In Proceedings of the 2006 international conference on Compilers, architecture and synthesis for embedded systems (CASES), pp. 234-241, 2006.
  11. Jung, H., Shim, H., Park, S., Kang, S., & Cha, J. LRU-WSR: integration of LRU and writes sequence reordering for flash memory. IEEE Trans. Consumer Electron., vol. 54, no. 3, pp. 1215-1223, 2008. https://doi.org/10.1109/TCE.2008.4637609
  12. Jo, H., Kang, J., Park, S., Kim, J., & Lee, J. FAB: flash-aware buffer management policy for portable media players. IEEE Trans. Consumer Electron., vol. 52, no. 2, pp. 485-493, 2006. https://doi.org/10.1109/TCE.2006.1649669
  13. Kim, H. & Ahn, S. BPLRU: a buffer management scheme for improving random writes in flash storage. In Proceedings of the 6th USENIX Conference File and Storage Technologies (FAST), 2008.
  14. Kang, S., Park, S., Jung, H., Shim, H., & Cha, J. Performance trade-offs in using NVRAM write buffer for flash memory-based storage devices. IEEE Trans. Consumer Electron., vol. 58, no. 6, pp. 744-758, 2009.