Data Dependent Sparing to Manage Better-Than-Bad Blocks

作者：Maddah Rakan^*; Cho Sangyeun; Melhem Rami

来源：IEEE Computer Architecture Letters, 2013, 12(2): 43-46.

DOI：10.1109/L-CA.2012.20

• Sparing
• phase-change memory (PCM)
• flash memory
• solid-state drive (SSD)
• stuck-at faults

We forecast that proper handling of unreliable storage blocks (e. g., "bad block management" in solid-state drives) will remain critical for future systems built with advanced and emerging memory technologies. This paper argues that the conventional block retirement and sparing approach-a block is retired as soon as it shows faulty behavior-is overly conservative and inefficient. We observe that it is highly unlikely that all faulty bits in a storage block manifest errors. Consequently, we propose data dependent sparing, a relaxed block retirement and sparing approach that recycles faulty storage blocks. At small management cost and with less than 1% sparing, data dependent sparing achieves the same lifetime as the conventional approach with 20% sparing.

• 出版日期2013-12