Adaptive Wear-Leveling in Flash-Based Memory

The paper presents an adaptive wear-leveling scheme based on several wear-thresholds in different periods. The basic idea behind this scheme is that blocks can have different wear-out speeds and the wear-leveling mechanism does not conduct data migration until the erasure counts of some hot blocks hit a threshold. Through a series of emulation experiments based on several realistic disk traces, we show that the proposed wear-leveling mechanism can reduce total erasure counts and yield uniform erasure counts among all blocks at the late lifetime of the storage devices. As a result, not only can the performance of storage systems be advanced, the lifespan of the flash-based memory can also be extended to a certain degree.