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RMSS: an efficient recovery management scheme on NAND flash memory based solid state disk

In many consumer electronics such as digital camcorders, notebooks, and tablet PCs, hard disk drive (HDD) has been replaced with NAND flash memory based solid state disk (SSD) because of its fast speed and low power consumption. However, since SSD inherits the limitations of NAND flash memory such as erase-before-write architecture and asymmetric read, write, and erase speeds, it may result in severe performance degradation to implement a B-tree on SSD. To address these problems, several methods exploiting the buffer have been proposed so far. However, they have faced with the recovery problem because all index data in the buffer are lost when a sudden power-off occurs. In this paper, we introduce a method called RMSS (recovery management scheme on SSD) that supports an efficient recovery mechanism when a B-tree is built on SSD. Since RMSS flushes all index data and creates a checkpoint whenever updating the root node, it can stably restore the index structure into up-to-date and consistent state. Consequently, RMSS efficiently implements a B-tree on SSD by using a buffer, and also recovers the original B-tree when a power failure occurs. We show the performance of RMSS on SSD through various experiments.