High durability in NAND flash memory through effective page reuse mechanisms
Kwangyoon Lee, Alex Orailoğlu · 2010
In this paper, we introduce a highly effective page reuse mechanism to reduce the amount of block erasures and page programming in NAND based primary memory architectures. The proposed techniques provide a very high rate of page reuse by effectively incorporating bit differences in page updates along with a reduction in bit unprogrammability by minimizing programming interference among adjacent pages. We also propose an effective block reclamation scheme to alleviate overall programming stress in a block so as to reduce the probability of run-time cell defects. The page reordering scheme can further increase page reusability by reducing run-time programming disturbance. The experimental results show that our proposed techniques significantly diminish the amount of block reclamation and consequently enhance the durability of the NAND flash based storage systems. Furthermore, by alleviating overall bit stress in NAND flash memory, the probability of bit failure of each cell is also significantly reduced, enabling the construction of more reliable and durable NAND flash based memory.