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ABSTRACT

The use of NAND flash memory for building permanent storage has been increasing in many embedded systems due to properties such as non-volatility and low energy consumption. The persistent requirements for high storage capacity have given rise to the increase of bit density per cell as in multi-level cells but this has come at the expense of performance and has resulted in degradation of durability. In this paper, we introduce a complementary approach to boost the performance and durability of MLC-based storage systems by employing a non-volatile buffer that temporarily holds the data heading to MLCs. We also propose algorithms to efficiently eliminate unnecessary write and erase operations in MLCs by performing a pre-merge in the buffer. Our experiments show that the proposed approach can increase performance by up to 4 times and durability by 4 times by adding only a small hardware cost.

REFERENCES

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INDEX TERMS

Primary Classification:
  C. Computer Systems Organization
  C.3 SPECIAL-PURPOSE AND APPLICATION-BASED SYSTEMS

Additional Classification:
  D. Software
  D.4 OPERATING SYSTEMS
      D.4.2 Storage Management

General Terms:
Algorithms, Design, Management, Performance

Keywords:
flash memory, flash translation layer, storage systems