Memory Controller Over-Sampling Read Recovery for Failed Stripe Pages
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current storage devices face challenges in efficiently recovering data from multiple memory devices when read operations fail, particularly due to errors in volatile memory, leading to data loss and reduced reliability.
Innovation Solution
A memory controller with a read operation controller, over-sampling read voltage determiner, error bit recovery, and error corrector is implemented to control multiple memory devices. This controller performs soft read operations, determines over-sampling read voltages, recovers error estimation bits, and performs error correction decoding on conversion data across different memory devices within a stripe.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If read operations are performed on multiple pages in different memory devices, then data retrieval capability is improved, but data loss occurs when read operations fail
Solution Approach 1:
The patent performs preliminary actions by conducting soft read operations and determining over-sampling read voltages before the actual read operation fails completely. This allows the system to proactively identify pages that may fail and prepare recovery strategies in advance, preventing data loss before it occurs.
Solution Approach 2:
The system implements feedback mechanisms by monitoring read operation results and using soft read data to determine whether pages have failed. Based on this feedback, the system dynamically adjusts by performing over-sampling read voltages and recovering error estimation bits, creating a closed-loop control system that prevents data loss.
2Reliability
If over-sampling read voltages are determined based on soft read data, then error recovery capability is improved, but system complexity increases
Solution Approach 1:
The system performs self-service by automatically determining over-sampling read voltages based on soft read data without requiring external intervention. The memory controller autonomously identifies failed pages, determines appropriate voltages, and recovers errors, reducing the need for complex external error correction mechanisms.
Solution Approach 2:
The patent changes physical parameters by adjusting read voltages dynamically based on soft read data characteristics. By modifying the voltage parameter in response to detected errors, the system improves error recovery capability without requiring fundamentally new hardware components, thus limiting the increase in system complexity.
3Measurement precision
If error estimation bits are recovered using over-sampling read data, then data accuracy is improved, but processing time increases
Solution Approach 1:
The system applies partial action by performing over-sampling read operations only on specific pages that are identified as failed through soft read data analysis, rather than re-reading all pages. This selective approach recovers error estimation bits accurately while minimizing the additional processing time required.
Solution Approach 2:
By performing soft read operations and identifying failed pages in advance, the system prepares a targeted list of pages requiring over-sampling read operations. This preliminary identification reduces the overall processing time by avoiding unnecessary re-reads of successful pages while still achieving high data accuracy for recovered pages.
Data Source
AI summary
A memory controller includes: a read operation controller for controlling the plurality of memory devices to perform read operation on a plurality of pages included in one stripe; an over-sampling read voltage determiner for determining over-sampling read voltages, based on soft read data of a selected page among at least two pages, when read operations on the at least two pages among the plurality of pages fail; an error bit recovery for recovering error estimation bits included in read data of the selected page, based on an over-sampling read data of the selected page, which is acquired using the over-sampling read voltages; and an error corrector for performing error correction decoding on conversion data obtained by recovering the error estimation bits included in the read data of the selected page. The plurality of pages included in one stripe is included in different memory devices among the plurality of memory devices.