Storage Extent Mapping for Defective Sector Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hard disk drives (HDDs) face issues with primary and grown defective sectors, which are not efficiently managed, leading to waste and a shorter service life due to the limited availability of backup sectors.
Innovation Solution
A method and device for storage management that divides storage media into two groups of extents, where one group is reserved as backup, allowing defective extents to be mapped to backup extents, thereby extending the service life and reducing waste by reconstructing data using a redundant array of independent disks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If backup sectors are used to map defective sectors in traditional HDD management, then defective sectors can be handled, but the service life is limited due to the finite number of backup sectors
Solution Approach 1:
The storage medium is divided into multiple extents (logical continuous blocks), and a separate group of extents is allocated as backup extents. This segmentation allows the system to manage defective areas at the extent level rather than sector level, providing more granular control and extended backup capacity.
Solution Approach 2:
The patent introduces a new dimension of management by organizing storage into extents (groups of continuous blocks) rather than managing individual sectors. This dimensional change from sector-level to extent-level management enables more efficient use of backup resources and extends the overall service life.
2Reliability
If defective sectors are mapped to backup sectors using firmware, then data integrity is maintained, but storage capacity is wasted due to the hidden and limited backup sectors
Solution Approach 1:
By segmenting the storage medium into extents and creating a separate backup extent group, the system maintains data integrity through mapping while reducing waste. The extent-level segmentation allows for more efficient backup utilization compared to traditional sector-level mapping.
3Measurement precision
If the storage medium is divided into smaller units for defect management, then defect mapping precision is improved, but the number of management units increases leading to higher complexity
Solution Approach 1:
The patent applies segmentation at the extent level (groups of continuous blocks) rather than individual sector level. This provides sufficient precision for defect mapping while avoiding the excessive complexity that would result from managing every individual sector separately.
Solution Approach 2:
The system applies different management approaches to different parts of the storage medium: the first group of extents is managed for normal operations while the second group is reserved as backup. This local differentiation optimizes both precision and complexity by applying granular management only where needed.
Data Source
AI summary
Embodiments of the present disclosure provide a method for storage management and a storage device. The method for storage management comprises; dividing a first storage medium into a first group or extents and a second group of extents, each extent including a plurality of logically continuous blocks of the first storage medium, the second group being reserved as backup extents; detecting whether an extent in the first group of extents is a defective extent; and disabling the extent in the first group of extents and mapping a logical address of the extent in the first group of extents to an extent in the second group of extents, in response to detecting that the extent in the first group of extents is a defective extent. With the embodiments of the present disclosure, a service life of storage device may be prolonged.