Abstract
Today, flash memory is widely used for various kinds of products. Unlike a hard disk, it has neither mechanical parts nor seek-delay. Therefore, a user may expect steady performance under disk fragmentation in flash storage. However, most commercial products do not satisfy this expectation. For example, a SDMMC card can be written in 18.7Mbytes/sec speed sequentially, but its write speed is slowed down to 3.2Mbytes/sec when it is seriously fragmented. It is only 18% of the original performance.
In this paper, we analyze the reason for performance degradation in a flash disk, and propose an FTL level optimization technique, named the page padding method, to lessen the fragmentation effect. We applied the technique to the Log-block FTL algorithm and showed that it can enhance write performance by 150% in a severely fragmented flash disk.
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© 2007 Springer-Verlag Berlin Heidelberg
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Kim, H., Kim, JH., Choi, S., Jung, H., Jung, J. (2007). A Page Padding Method for Fragmented Flash Storage. In: Gervasi, O., Gavrilova, M.L. (eds) Computational Science and Its Applications – ICCSA 2007. ICCSA 2007. Lecture Notes in Computer Science, vol 4705. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-74472-6_13
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DOI: https://doi.org/10.1007/978-3-540-74472-6_13
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-74468-9
Online ISBN: 978-3-540-74472-6
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