Storage device management method based on failure prediction and automatic recovery

Abstract

This invention discloses a solid-state drive (SSD) management method based on fault prediction and automatic recovery. It dynamically calculates the health score of each storage module and automatically switches modules between normal mode, degraded mode, and isolation mode based on the score. When a module enters degraded mode, the controller divides the data into multiple independently movable data segments, which are then migrated sequentially to healthy modules according to risk priority. The local logical mapping table is updated immediately after each segment migration. During the migration process, the controller continuously evaluates the health score. If the score rises to a preset threshold, the remaining data segment migration and new data write rates are adjusted until the module recovers to normal mode. If the health score remains below the threshold, the module is permanently switched to isolation mode, writes are prohibited, and the data is logically mapped to other healthy modules. This method enables proactive protection and automatic recovery of SSD data security, improving the reliability and lifespan of the storage system.

Description

1. Description of a Storage Device Management Method Based on Fault Prediction and Automatic Recovery Technical Field This invention relates to data management technology for solid-state drives (SSDs), and more particularly to a storage device management method based on fault prediction and automatic recovery. This method aims to improve the reliability and lifespan of each storage module within an SSD. Through dynamic monitoring of health scores, segmented data migration, real-time logical mapping updates, and automatic isolation control, it reduces the risk of data loss, improves write performance, and ensures stable operation of the storage system. Background Art In the field of SSD data storage management, the system needs to continuously monitor the health status of each storage unit and take corresponding measures for possible faults or performance degradation. However, existing technologies do not adequately consider the dynamic changes in data distribution, local aging, and write load within storage units, and have limited overall coordination capabilities for data migration strategies and write operations, potentially leading to a trade-off between performance and reliability. Furthermore, existing methods often use static or preset conditions as the basis for health judgment, lacking strategies for automatically adjusting to the real-time health status of storage units. Especially when dealing with locally aged or high-risk data, they cannot flexibly adjust the data migration and write rhythm, potentially resulting in low migration efficiency or excessive interference with normal operations. Therefore, when dealing with dynamic changes in the health status of storage units, localized data aging, and the need for segmented data migration, existing technologies still suffer from the problem of balancing reliability and efficiency. Summary of the Invention: One objective of this invention is to provide a storage device management method based on fault prediction and automatic recovery. This method can assess the health status of each storage module in real time and dynamically adjust data migration and write operations based on the module's health score. Through segmented data migration and operation timing control, it improves module reliability and extends its lifespan while reducing the impact on normal data writing and improving the overall performance and stability of the storage system. To achieve the above objectives, the present invention proposes a storage device management method based on fault prediction and automatic recovery, applicable to solid-state drives, comprising: (A) a health assessment and state switching step: the controller of the computer system continuously monitors the trend changes of a plurality of storage behavior indicators, calculates a health score for a plurality of storage modules, and automatically switches the storage modules between three states: a normal mode, a degraded mode, and an isolation mode based on the health score; wherein, the storage behaviors include a write error event frequency, an erase / write latency offset, and a retention error increase, and the storage modules refer to storage units composed of at least one flash memory chip or its logical sub-region; wherein, the health score is dynamically calculated based on the distribution of valid data, local aging degree, and changes in write load within the storage modules, so that data migration can affect the health score in real time; (B) a segmented migration step: when any storage module enters the degraded mode,Perform actions b1 to b4; b1. The controller, based on logical address continuity, physical page clustering, or block correspondence, divides the existing valid data within the storage module entering the degraded mode into multiple independently movable data segments; wherein each data segment corresponds to at least one logical address range and at least one physical page group; b2. For each data segment, the controller determines the risk index of the data segment based on the local aging degree of its respective physical page group, and sorts them from high to low risk to form a segment migration sequence; b3. The controller migrates the data segment sequentially according to the segment migration sequence, starting with the data segment with the highest risk, to any other storage module belonging to the normal mode; b4. After each data segment migration is completed, the controller immediately updates the local logical mapping table corresponding to the data segment, so that the logical location of the data segment in the new module takes effect immediately, without waiting for all other data segments that have not yet been migrated to complete their migration; (C) Migration Real-Time Assessment Steps: When the abnormal storage module is at the beginning of the migration of data segments, new data writing is paused. After each data segment is migrated, the controller immediately recalculates the health score of the abnormal storage module. If the health score rises above a first preset threshold, the migration of the remaining data segments continues and new data writing is performed synchronously. The migration timing of the remaining data segments remains at the original speed, while the timing of new data writing is adjusted to twice the original timing to reduce instantaneous write speed. If the health score rises above a second preset threshold, the previously abnormal storage module is switched to normal mode, the migration of the remaining data segments is stopped, and the new data writing timing is restored to normal write speed. The second preset threshold is higher than the first preset threshold. The remaining data segments after the migration stops remain in the original storage module and are re-included in the subsequent relocation or isolation determination process based on the health score during subsequent state switches. (D) Permanent isolation steps: If the health score of any storage module is initially determined to be in the isolation mode, write operations are permanently prohibited, and the relevant logical mapping is replaced by another storage module in the normal mode; or if the health score of a storage module is initially determined to be in the degraded mode, and before reaching the first preset threshold, if the health score after moving N data segments is still lower than or equal to the health scores of (N-5) moved segments, the controller switches the storage module to the isolation mode, permanently prohibits write operations, and replaces the relevant logical mapping by another storage module in the normal mode; where N is an integer greater than or equal to 5. In summary, the storage device management method provided by this invention, through health score-driven segmented data migration and dynamic operation timing control, can not only adjust the data processing strategy of abnormal modules in real time to avoid data loss or premature module isolation, but also maintain the high-efficiency write performance of normal modules.This invention further improves the overall reliability, lifespan, and system performance of solid-state drives (SSDs), and reduces data access latency and system congestion caused by module aging or partial failures. HK 20134900 A 3 Figure 1 is a flowchart of a preferred embodiment of the invention. Detailed Description: To enable those skilled in the art to clearly understand the technical content of the invention, the following embodiments are described in conjunction with the accompanying drawings to further illustrate the storage device management method based on fault prediction and automatic recovery provided by the present invention. Please refer to Figure 1, which is a flowchart of a preferred embodiment of the invention. This embodiment of a storage device management method based on fault prediction and automatic recovery is applicable to solid-state drives (SSDs). First, the (A) health assessment and state switching step is performed. In this embodiment, the controller in the computer system of the SSD continuously monitors multiple storage behavior indicators for each storage module and calculates a module health score based on the changing trends of these indicators. The storage behavior indicators include write error event frequency, erase / write latency offset, and retention error increase, etc. The write error event frequency refers to the number of write failures occurring per unit time, which the controller can count using a counter. The erase / write latency offset represents the deviation of the actual erase / write time from the nominal specification; a large deviation may indicate partial aging of the flash memory or strain on the flash controller resources. The retention error increase refers to the increase in the tolerable errors in the retention area, reflecting a weakening of the module's fault tolerance. Each storage module can consist of a single flash memory die or be formed by logical sub-regions, serving as an independent storage unit. A logical sub-region refers to multiple independently manageable page groups divided on a physical die, each with independent erase / write counts and error records. Based on the calculated health score, the controller can automatically switch each storage module to one of three modes: normal mode, degraded mode, or isolation mode. Normal mode indicates that the storage module is in good health, and data can be freely read and written. Degraded mode indicates that the storage module's health is slightly lower, and the controller may limit simultaneous writes, adjust data migration strategies, or extend write intervals to prevent further deterioration. Isolation mode indicates that the storage module's health has severely deteriorated, and the controller will prohibit writes and transfer the original module's logical mapping to other healthy modules. Furthermore, the health score comprehensively considers the distribution of valid data within the storage module, the degree of local aging, and changes in write load, so that data migration or write operations can immediately affect the health score. For example, if a segment of the module is subjected to high-frequency writes for a long period and the erase / write cycle is close to the specification limit, the controller will include that segment in the health score calculation, reflecting the overall risk of the module; if the data is evenly distributed and the load is low, the health score will remain at a higher value, and the module can operate normally. The controller can use sliding windows, weighted averages, or other statistical methods to integrate various indicators and generate a single health score to provide a basis for automatic switching decisions. Through this mechanism,The health status of a module is reflected in the control strategy in real time, providing a basis for subsequent segmented data migration or isolation determination. Next, the segmented migration step (B) is executed. When any storage module enters degraded mode, the HK 20134900 A4 controller performs segmented migration of the existing valid data within that module. Valid data refers to data that is still referenced by the system or has practical use value, not deleted or marked as free areas. First, in detailed action b1, the controller divides the valid data within the degraded module into multiple independently movable data segments based on logical address continuity, physical page clustering, and block correspondence. Each data segment corresponds to at least one logical address range and at least one physical page group, allowing each data segment to be moved independently without affecting access to other data segments. For example, if a module contains 100 consecutive logical pages, with each 10 pages forming a physical page group, then 10 data segments can be formed, each of which can be moved independently to other healthy modules. Next, in detailed action b2, the controller assesses risk indicators for each data segment. Risk indicators are calculated based on the local aging level, cumulative write count, and error event frequency of the physical page group to which the data segment belongs. Local aging level can be determined by comparing the page group's erase / write cycle count with its preset durability; a page group nearing its durability limit carries a higher risk. All data segments are sorted from highest to lowest risk, forming a segmented migration sequence to ensure that high-risk data segments are moved first. For example, if data segments A, B, and C have local aging levels of 90%, 75%, and 60% respectively, the migration order is A → B → C. Following this, in detailed action b3, the controller sequentially moves the data segments to other storage modules in normal mode according to the segmented migration sequence. The migration can be completed using DMA or built-in instructions of the flash memory controller, ensuring data consistency and integrity during the migration process. Continuing on, in detailed action b4, after each data segment migration is completed, the controller immediately updates the local logical mapping table corresponding to that data segment, making the data effective immediately in the new module's logical location without waiting for other data segments to be migrated. For example, after the first data segment migration is completed, the system can immediately read and write that data segment from the new module. Subsequent data segments remain in the original module or are being migrated, without affecting existing access. Accordingly, through this segmented migration mechanism, the controller can precisely control the data migration order and speed, reducing the impact on normal data writing operations, and providing a basis for real-time adjustments when the health status of a degraded module improves or deteriorates. Compared to traditional full module migration, this strategy can effectively improve migration efficiency and reduce the impact on system performance. Following steps (A) and (B), step (C) of real-time migration evaluation is performed when an abnormal storage module begins data segment migration.The controller first suspends new data writing operations on the faulty storage module. This design primarily aims to prevent new write loads from further exacerbating the module's localized aging and to ensure data integrity during the initial relocation phase. During the pause, the module only relocates existing data segments and does not bear new write pressure. After each data segment migration is completed, the controller immediately recalculates the health score of the faulty module. The health score is based on a combination of factors, including the module's error rate, changes in recent write / erase cycles, reported internal device health parameters, and changes in heat or pressure caused by the relocation activity. Real-time calculation after migration accurately reflects whether the module shows signs of stabilization after partial data unloading. Specifically, if the health score rises above the first preset threshold, the controller initiates a synchronization operation, allowing the migration of remaining data segments to proceed simultaneously with new data writing operations. In this state, the migration timing of the remaining data segments remains unchanged, but the timing of new data writing operations is adjusted to twice the original cycle to reduce instantaneous write speed. For example, if the original write interval is 1ms, it will be extended to 2ms at this stage to prevent the module from being subjected to excessive load immediately after stabilizing and deteriorating again. Furthermore, if the health score continues to improve and rises above the second preset threshold (which is higher than the first threshold), the controller will switch the module from abnormal mode back to normal mode. At this time, the remaining unmigrated data segments stop migrating and remain in the original storage module. Since the module has returned to a normal operating state, the data does not need to be forcibly migrated to other modules. Subsequently, the new data write timing returns to normal speed and is no longer subject to speed-down control. As for the remaining data segments retained after the migration stops, the controller will determine in subsequent evaluations whether they need to be reintroduced into the migration process or returned to isolation state based on the health score. For example, if the module experiences abnormalities again in subsequent operation and its health score decreases, the previously retained data segments may be reinstated on the migration list; conversely, if the health remains stable, the retained data segments can continue to serve in the original module. Therefore, the above design allows for a highly flexible data migration strategy, preventing excessive migration and enabling modules to quickly return to normal operation after stabilization, effectively improving the overall system's durability and performance maintenance capabilities. Following steps (A), (B), and (C), step (D) permanent isolation is executed. When the controller determines during the initial evaluation phase that the health score of a storage module is in isolation mode, that module is considered unable to safely undertake any data write operations. In this case, the controller immediately permanently disables write operations on that module and reassigns all logical address ranges originally belonging to that module to other storage modules that are still in normal mode. This action also includes updating the logical mapping table, ensuring that subsequent data writes and reads no longer touch the abnormal module.To prevent data from falling into unreliable areas, if the storage module is initially classified as degraded, the controller will migrate the data in the module segment by segment according to the aforementioned segmented migration process. During this degrade period, the system observes its recovery trend through health scores after continuous migrations. Specifically, after migrating the Nth data segment, the controller obtains the health score at that point; simultaneously, the controller also backtracks to the health score when the (N-5)th data segment migration was completed and compares the changes between the two. If the module's health score is still lower than or equal to the health score when the (N-5)th data segment migration was completed after migrating N data segments, it indicates that the module has not shown any improvement after multiple migrations and may even continue to deteriorate. This situation means that the local aging of the module is not caused by a single pressure or instantaneous load, but may have comprehensive, irreversible, or unstable degradation characteristics. Therefore, continuing to migrate HK 20134900 A 6 will not only not help recovery, but may also delay the isolation time and increase data risk. Based on the above determination, the controller will switch the storage module from degraded mode to isolated mode at that time point and also apply a permanent write restriction. Simultaneously, all logical address mappings belonging to this module will be immediately transferred to other normal mode storage modules, preventing this module from participating in subsequent data writing and migration operations. Here, the parameter N is an integer greater than or equal to 5 to ensure that the health score comparison has a sufficient observation span to avoid fluctuations caused by a single or very short-term migration misleading the isolation determination. By comparing the health scores at time points N and (N-5), the overall trend of the module after multiple consecutive data segment migrations can be observed, distinguishing whether the module's health status shows a gradual recovery, remains stable, or continues to decline. The technical significance of this comparison method is that the module may temporarily reduce its load due to partial unloading during data migration, but a short-term increase in the health score does not mean that the module has fully recovered; conversely, a momentary decrease in write load may create a false recovery. By setting observation spans of N and (N-5), the interference of short-term fluctuations on judgment can be reduced, ensuring that isolation decisions reflect the long-term trend and true health status of the module. For example, in a practical case, if N=7, the system compares the health score after moving the 7th segment with the health score after moving the 2nd segment. If no significant improvement is observed, it indicates that the module's health status has not improved in the long term, and there may be comprehensive, irreversible, or unstable aging phenomena, thus requiring permanent isolation. This mechanism effectively distinguishes between "recoverable short-term anomalies" and "irreversible deep degradation," avoiding misjudgments of a module's continued usability due to a single instantaneous rebound, thereby improving data security, reducing system risk, and extending the reliable operating time of other healthy modules. Furthermore, this judgment method is applicable to storage systems of different sizes and configurations.This invention provides a consistent and predictable isolation strategy, enabling the system to maintain stability and data integrity under high load or long-term use. In summary, the storage device management method based on fault prediction and automatic recovery provided by this invention accurately reflects the health status of each storage module through real-time health score calculation and multi-level mode switching. It also provides a dynamic, segmented data migration and synchronous write strategy, effectively reducing the performance impact caused by full module relocation. Through segmented migration and risk prioritization, this method can prioritize high-risk data segments, ensuring data security and access consistency while maintaining system write performance. Utilizing health score threshold design and real-time monitoring, degraded modules can automatically adjust the data migration rhythm and new data write sequence according to the recovery rate, balancing module lifespan extension and system performance maintenance. When a module shows an irreversible or continuously deteriorating trend, it can be permanently isolated in a timely manner to prevent data loss or errors from spreading to normal modules, further improving the overall system reliability. Segmented relocation, real-time health score updates, and isolation judgment mechanisms enable the storage system to react quickly and accurately to localized aging, instantaneous high loads, or degradation caused by long-term use. This avoids excessive relocation or premature isolation, reduces resource waste, and extends module lifespan (HK 20134900 A 7), thereby improving the overall durability, data security, and operational stability of the storage system. It provides a reliable and predictable storage operation mode for multi-module, high-load environments. The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the invention; therefore, all equivalent changes and modifications made without departing from the scope of the invention should be covered within the patent scope of the present invention. Symbol Explanation (A)~(D) Step HK 20134900 A Claim 1. A storage device management method based on fault prediction and automatic recovery, applicable to solid-state drives, comprising: (A) Health assessment and state switching step: The controller of the computer system continuously monitors the trend changes of a plurality of storage behavior indicators, calculates a health score of a plurality of storage modules, and automatically switches the storage modules between three states: a normal mode, a degraded mode, and an isolation mode based on the health score; wherein, the storage behaviors include a write error event frequency, an erase / write delay time offset, and a retention error increase, and the storage modules refer to storage units composed of at least one flash memory chip or its logical sub-region; wherein, the health score is dynamically calculated based on the distribution of effective data, local aging degree, and changes in write load within the storage modules, so that data migration can affect the health score in real time; (B) Segmented migration step: When any storage module enters the degraded mode, actions b1 to b4 are executed; b1. The controller, based on logical address continuity, physical page clustering, or block correspondence, will retrieve the existing valid data within the storage module that has entered the degraded mode.b1. Divide the data segment into multiple independently movable segments; each data segment corresponds to at least one logical address range and at least one physical page group; b2. For each data segment, the controller determines the risk index of the data segment based on the local aging degree of the physical page group to which it belongs, and sorts them from high to low risk to form a segment migration sequence; b3. According to the segment migration sequence, the controller migrates the data segment with the highest risk sequentially to any other storage module belonging to the normal mode; b4. After each data segment migration is completed, the controller immediately updates the local logical mapping table corresponding to the data segment, so that the logical location of the data segment in the new module takes effect immediately, without waiting for all other data segments that have not yet been migrated to complete their migration; (C) Migration Real-Time Assessment Steps: When the abnormal storage module is at the beginning of the migration of data segments, new data writing is paused. After each data segment migration, the controller immediately recalculates the health score of the abnormal storage module. If the health score rises above a first preset threshold, the migration of the remaining data segments continues, and new data writing is performed synchronously. The migration timing of the remaining data segments remains at the original speed, while the timing of new data writing is adjusted to twice the original timing to reduce instantaneous write speed. If the health score rises above a second preset threshold, the previously abnormal storage module (HK 20134900 A) is switched to normal mode, the migration of the remaining data segments is stopped, and the new data writing timing is restored to normal write speed. The second preset threshold is higher than the first preset threshold. The remaining data segments after the migration stops remain in the original storage module and are re-included in the subsequent relocation or isolation determination process based on the health score during subsequent state changes. (D) Permanent isolation procedure: If the health score of any storage module is initially determined to be in the isolation mode, write operations are permanently disabled and the relevant logic mapping is replaced by another storage module in the normal mode; or if the health score of a storage module is initially determined to be in the downgrade mode, and before reaching the first preset threshold, if the health score after moving N data segments is still lower than or equal to the health score of (N-5) moved data segments, the controller switches the storage module to the isolation mode, permanently disables write operations, and replaces the relevant logic mapping by another storage module in the normal mode; where N is an integer greater than or equal to 5. 2 HK 20134900 A 1 Instruction Manual Drawings Figure 1 HK 20134900 A,

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