| 摘要 |
Embodiments of the present invention use high granularity reliability information (e.g., from individual pages, blocks, etc.) in a solid state storage device to vary the number of elements in each RAID stripe and to combine the elements in a stripe to achieve a more homogenous reliability metric across the device. In one embodiment, a reliability metric of a stripe group of storage elements is calculated based on monitored conditions of the storage elements such as erase counts, number of bit errors encountered, calculated voltage reference values, etc. The reliability metrics of the stripe groups are used to decide how many storage elements and which storage elements should be combined in the redundant RAID stripes to achieve a desired probability of data loss for the overall device. The target error probability could be fixed for the life of the storage device or adjusted as the device wide error rates increase. |
