Data Dependent Sparing to Manage Better-Than-Bad Blocks
The authors 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. They observe that it is highly unlikely that all faulty bits in storage block manifest errors. Consequently, they propose data dependent sparing, a relaxed block retirement and sparing approach that recycles faulty storage blocks.