zFTL: power-efficient data compression support for NAND flash-based consumer electronics devices

Flash translation layers play an important role in determining the storage performance and lifetime of NAND flash-based consumer electronics devices. In this paper, we present a flash translation layer called zFTL, which reduces the amount of data written to NAND flash memory by supporting on-line, transparent data compression based on the X-Match algorithm. To minimize compression overhead and power consumption, we also propose a novel prediction scheme that identifies incompressible data in advance without going through full compression. Our evaluations with five real-world workloads show that zFTL successfully enhances storage performance and lifetime by improving the write amplification factor (WAF) by a factor of 2.6 (geometric mean) compared to the case without compression support. In addition, we find that the proposed prediction scheme is effective in reducing power consumption by skipping compression for incompressible data.

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