CN120164510A

CN120164510A - Method, device, equipment and medium for accelerating NAND Flash background inspection health detection

Info

Publication number: CN120164510A
Application number: CN202510334384.9A
Authority: CN
Inventors: 范浩东; 苟荣松; 宋世磊
Original assignee: Chengdu Xinyilian Information Technology Co Ltd
Current assignee: Chengdu Xinyilian Information Technology Co Ltd
Priority date: 2025-03-20
Filing date: 2025-03-20
Publication date: 2025-06-17

Abstract

The embodiment of the invention discloses a method, a device, equipment and a medium for accelerating NAND FLASH background inspection health detection, relating to the technical field of SSD health detection, wherein the method comprises the steps of screening target physical blocks to be detected from a solid state disk; dividing WL in the target physical block into a plurality of target groups, traversing all the target groups, issuing a read command to a page in each target group, and judging whether the target group corresponding to the page has data abnormality or not based on the data read from the page. According to the invention, through screening the target blocks, the full-disk scanning can be avoided, the efficiency is improved, and through dividing the target groups and checking only one page of the target groups every time, whether the whole target groups are abnormal or not is accurately judged based on the condition of the page, so that the full-disk scanning is avoided, the scanning quantity can be effectively reduced, and the efficiency is improved.

Description

Method, device, equipment and medium for accelerating NAND FLASH background inspection health detection

Technical Field

The invention relates to the technical field of SSD health detection, in particular to a method, a device, equipment and a medium for accelerating NAND FLASH background inspection health detection.

Background

Solid state disk (Solid STATE DRIVE, SSD) presents multiple challenges in terms of data reliability due to the physical characteristics of NAND FLASH. On the one hand, NAND FLASH units have the phenomenon of Read Disturb (Read Disturb), namely when a certain memory unit is frequently Read, the threshold voltages of adjacent units may deviate to cause data errors, on the other hand, in practical application, the access address range of a user to the memory space often presents uneven distribution, part of blocks bear high-frequency writing/erasing operations for a long time, and other blocks are idle for a long time, and the load unbalance can aggravate the aging rate of the memory unit. Together, the above problems lead to a significant risk of increasing the number of erroneous bits (Failure Bit Count, FBC) in SSDs, especially in high-volume enterprise-level SSDs, which further increases due to high storage density and high data throughput, may cause uncorrectable data errors, severely threatening the stability of the business system.

To address FBC risks, the prior art generally employs a background patrol mechanism to evaluate health status by scanning the full disk blocks. However, the conventional solution has significant drawbacks:

The scanning efficiency contradicts the resource occupation, namely the whole-disk scanning of the SSD of the large-capacity enterprise level needs to traverse massive physical blocks, and the traditional timing scanning strategy is easy to be operated by user data to occupy resources when the system is under high load due to lower IO priority, so that the inspection process is frequently interrupted, and the overall time consumption is greatly increased;

The risk detection real-time performance is insufficient, namely the uniform scanning mode cannot be dynamically focused on a high-error probability area (such as a frequently accessed block or a block close to the erasing service life), so that the identification of the risk block is delayed, and early warning or migration is difficult in time before the occurrence of data errors;

The resource competition causes performance fluctuation, namely the background inspection and the user IO operation share bandwidth and computational resources, especially in the error correction decoding (such as LDPC) link, access delay can be aggravated due to resource competition, and business service quality is affected.

Although the prior art attempts to improve the above problems by optimizing the scanning frequency or introducing a local scanning strategy, the core of the prior art still relies on static rules, and lacks the capability of dynamic sensing and adaptive adjustment of the running state of the SSD (such as real load, block error rate trend and temperature condition), which results in low resource scheduling efficiency and difficulty in balancing the contradiction between the timeliness of risk detection and the performance loss of the system. Therefore, how to design an efficient self-adaptive inspection mechanism, quickly locate potential risk blocks on the premise of minimizing resource occupation, avoid service read error data, and ensure user IO performance stability at the same time, has become a technical bottleneck to be broken through in the enterprise-level SSD field.

Disclosure of Invention

The embodiment of the invention provides a method, a device, equipment and a medium for accelerating NAND FLASH background inspection health detection, which aim to solve at least one technical problem in the background technology.

In a first aspect, an embodiment of the present invention provides a method for accelerating NAND FLASH background inspection health detection, including:

screening a target physical block to be detected from the solid state disk;

dividing WL (Word Line) in the target physical block into a plurality of target groups;

Traversing all target groups, and issuing a read command to one page in each target group;

And judging whether the target group corresponding to the page has data abnormality or not based on the data read from the page.

The further technical scheme is that the screening of the target physical block to be detected from the solid state disk comprises the following steps:

and selecting the physical block storing the effective data from the solid state disk as the target physical block.

The further technical scheme is that the dividing the WL in the target physical block into a plurality of target groups includes:

acquiring a test result of a medium test of WL in the target physical block;

WL in the target physical block is divided into a plurality of target groups based on the test result.

numbering the pages in the target group;

And correspondingly reading the data of the pages with corresponding numbers in each target group according to the times of traversing all the target groups.

The further technical scheme is that the judging whether the target group corresponding to the page has data abnormality based on the data read from the page comprises:

Counting the number of error bits in the page;

if the number of the error bits in the page is larger than a preset number threshold, judging that the target group corresponding to the page has data abnormality.

The method further comprises the following steps:

and if the target group has data abnormality, performing abnormality processing on the target group.

The further technical scheme is that the performing exception handling on the target group includes:

Carrying out full page scanning on the target group with the abnormality to confirm the abnormal page;

and migrating the abnormal page data to a normal physical block.

In a second aspect, an embodiment of the present invention further provides an apparatus for accelerating NAND FLASH background inspection health detection, which includes a unit for executing the above method.

In a third aspect, an embodiment of the present invention further provides a computer device, which includes a memory and a processor, where the memory stores a computer program, and the processor implements the method when executing the computer program.

In a fourth aspect, embodiments of the present invention also provide a computer readable storage medium storing a computer program which, when executed by a processor, implements the above method.

The embodiment of the invention provides a method, a device, equipment and a medium for accelerating NAND FLASH background inspection health detection. The method for accelerating NAND FLASH background inspection health detection comprises the steps of screening target physical blocks to be detected from a solid state disk, dividing WL in the target physical blocks into a plurality of target groups, traversing all the target groups, issuing a read command to one page in each target group, and judging whether the target group corresponding to the page is abnormal or not based on data read from the page. According to the invention, through screening the target blocks, the full-disk scanning can be avoided, the efficiency is improved, and through dividing the target groups and checking only one page of the target groups every time, whether the whole target groups are abnormal or not is accurately judged based on the condition of the page, so that the full-disk scanning is avoided, the scanning quantity can be effectively reduced, and the efficiency is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a flow chart of a method for accelerating NAND FLASH background inspection health detection according to an embodiment of the present invention;

Fig. 2 is a schematic block diagram of a computer device according to an embodiment of the present invention.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are some, but not all embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

It should be understood that the terms "comprises" and "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It is also to be understood that the terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in this specification and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It should be further understood that the term "and/or" as used in the present specification and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes such combinations.

As used in this specification and the appended claims, the term "if" may be interpreted as "when..once" or "in response to a determination" or "in response to detection" depending on the context. Similarly, the phrase "if a determination" or "if a [ described condition or event ] is detected" may be interpreted in the context of meaning "upon determination" or "in response to determination" or "upon detection of a [ described condition or event ]" or "in response to detection of a [ described condition or event ]".

Referring to fig. 1, an embodiment of the present invention provides a method for accelerating NAND FLASH background inspection health detection, which includes the following steps:

s1, screening target physical blocks to be detected from the solid state disk.

In the implementation, the physical block storing the effective data is selected from the solid state disk as the target physical block.

In the embodiment of the invention, only the physical blocks (blocks) storing valid data are traversed. Empty blocks (physical blocks without valid data) have no patrol value, and skipping such blocks can avoid invalid resource consumption. The area for actually storing the data is focused, so that the checking range can be effectively reduced, and the efficiency is improved.

S2, dividing WL in the target physical block into a plurality of target groups.

In particular implementations, there are differences in error rates due to different WL manufacturing differences or different frequency of use within the same block. WL with similar error risks are classified through grouping, so that a risk grade label is formed, and subsequent differential inspection is facilitated.

In some embodiments, for example, the step of dividing the WL in the target physical block into a plurality of target groups in the present embodiment specifically includes the steps of acquiring a test result of a media test of the WL in the target physical block, and dividing the WL in the target physical block into a plurality of target groups based on the test result.

In specific implementation, WL refers to the minimum unit of storage medium programming, and early medium test refers to systematic performance evaluation test performed on WL in storage medium (NAND flash) in SSD lifecycle (such as factory test, first initialization, and periodic background maintenance).

Core detection metrics include, but are not limited to:

Original error rate (Raw Bit Error Rate, RBER), the number of original error bits that were not corrected when the data was read;

program/erase delay (P/E Latency), the time-consuming write or erase operations;

Number of erasures (P/E Cycles) the WL experiences cumulative number of erasures;

data retention capability-stability of stored charge at a particular temperature/time.

The grouping logic based on the test results may be specifically as follows:

1. Data preprocessing

And (3) normalization processing, namely mapping each index to a 0-1 interval and eliminating unit difference.

Feature extraction-the risk score is calculated by weighting the test data for each WL, for example:

Risk score = α x RBER + β x P/E delay + γ x number of erasures + δ x retention decay rate

Wherein, alpha, beta, gamma and delta are weight coefficients which can be dynamically adjusted according to SSD model/use scene, and the invention is not particularly limited.

2. Grouping strategy

Principle, risk homogeneity (small intra-group differences) and inter-group heterogeneity (large inter-group differences). Based on the calculated risk scores of the WLs, the WLs are grouped, for example, the risk scores are divided into a plurality of ranges, and each range corresponds to one target group.

Dynamic adjustment:

after each inspection, recalculate each WL risk score

If a WL score deviates from the current group mean by more than a threshold (e.g., ±15%), it is migrated to the adjacent risk level group.

S3, traversing all target groups, and issuing a read command to one page in each target group.

In specific implementation, every time the inspection is performed, all target groups are traversed, and a read command is issued to one page in each target group. The repeated inspection of the same page is avoided, and the single inspection load is reduced by inspecting the pages covering different areas in the block in turn and inspecting only a small number of pages (such as 1 page in each group) of each group at a time.

It will be appreciated that step S3 is performed periodically, i.e. once per preset inspection cycle.

In some embodiments, for example, in the present embodiment, the step of "traversing all target groups and issuing a read command to one page in each target group" specifically includes the steps of numbering pages in the target groups, and correspondingly reading data of pages with corresponding numbers in each target group according to the number of times of traversing all target groups.

In particular implementations, pages in the target group are numbered, for example, with natural numbers 1, 2, 3.

First traversing, issuing a read command to a first Page (Page) of each target group;

and (3) sequentially increasing Page numbers of spot checks in each target group (such as 1 st check Page 1 and 2 nd check Page 2) in each subsequent inspection. After all pages within the target set have been read, the reading is restarted from the first page.

S4, judging whether the target group corresponding to the page has data abnormality or not based on the data read from the page.

In the implementation, if the data of the page is abnormal, the target group corresponding to the page is considered to be abnormal. In the embodiment of the invention, the overall risk in the group is inferred through sampling statistics, so that the overhead of full page scanning is avoided.

In some embodiments, for example, in the present embodiment, the step of determining whether the target group corresponding to the page has a data exception based on the data read from the page specifically includes the steps of counting the number of erroneous bits in the page, and if the number of erroneous bits in the page is greater than a preset number threshold, determining that the target group corresponding to the page has a data exception.

In particular, the number threshold may be set by a person skilled in the art, which is not particularly limited in this invention, and the setting of the number threshold may be dynamically adjusted (e.g. according to the life stage of the SSD) to balance the false alarm rate and the omission rate.

In some embodiments, for example, the method further includes performing exception handling on the target group if there is a data exception for the target group.

Specifically, the method comprises the steps of carrying out full page scanning on the target group with the abnormality to confirm the abnormal page, and migrating the abnormal page data to a normal (fault-free) physical block. Further, the block corresponding to the target group may also be marked as a high risk area.

In the embodiment of the invention, the resource waste of full-quantity scanning can be reduced by sampling early warning and accurate positioning, and all abnormal pages can be accurately found, and further, business IO is preferentially ensured not to be blocked by data migration and marking operation.

The embodiment of the invention provides a method for accelerating NAND FLASH background inspection health detection, which comprises the steps of screening target physical blocks to be detected from a solid state disk, dividing WL (WL) in the target physical blocks into a plurality of target groups, traversing all the target groups, issuing a read command to a page in each target group, and judging whether the target group corresponding to the page has data abnormality or not based on data read from the page. According to the invention, through screening the target blocks, the full-disk scanning can be avoided, the efficiency is improved, and through dividing the target groups and checking only one page of the target groups every time, whether the whole target groups are abnormal or not is accurately judged based on the condition of the page, so that the full-disk scanning is avoided, the scanning quantity can be effectively reduced, and the efficiency is improved.

Corresponding to the method for accelerating NAND FLASH background inspection health degree detection, the invention also provides a device for accelerating NAND FLASH background inspection health degree detection. The acceleration NAND FLASH background inspection health detection device includes a unit for executing the acceleration NAND FLASH background inspection health detection method, and the acceleration NAND FLASH background inspection health detection device can be configured in a desktop computer, a tablet computer, a portable computer, or the like. Specifically, the device for accelerating NAND FLASH background inspection health detection comprises:

The screening unit is used for screening the target physical blocks to be detected from the solid state disk;

A dividing unit for dividing WL in the target physical block into a plurality of target groups;

The traversing unit is used for traversing all target groups and issuing a read command to one page in each target group;

And the judging unit is used for judging whether the target group corresponding to the page has data abnormality or not based on the data read from the page.

In some embodiments, for example, in this embodiment, the screening the target physical block to be detected from the solid state disk includes:

In some embodiments, for example, the dividing WLs in the target physical block into a plurality of target groups includes:

acquiring a test result of a medium test of WL in the target physical block;

In some embodiments, for example, in this embodiment, the traversing all target groups issues a read command to one page in each target group;

numbering the pages in the target group;

In some embodiments, for example, in this embodiment, the determining whether the target group corresponding to the page has a data exception based on the data read from the page includes:

Counting the number of error bits in the page;

In some embodiments, for example, in this embodiment, the device for accelerating NAND FLASH background inspection health detection further includes:

and the exception handling unit is used for handling the exception of the target group if the target group has data exception.

In some embodiments, for example, the performing exception handling on the target group includes:

and migrating the abnormal page data to a normal physical block.

It should be noted that, it can be clearly understood by those skilled in the art that the device for accelerating NAND FLASH background inspection health detection and the specific implementation process of each unit can refer to the corresponding description in the foregoing method embodiment, and for convenience and brevity of description, the description is omitted here.

The means for accelerating NAND FLASH background inspection health detection described above may be implemented in the form of a computer program that can be run on a computer device as shown in fig. 2.

Referring to fig. 2, fig. 2 is a schematic block diagram of a computer device according to an embodiment of the present invention. The computer device 500 may be a terminal or a server, where the terminal may be an electronic device with a communication function, such as a smart phone, a tablet computer, a notebook computer, a desktop computer, a personal digital assistant, and a wearable device. The server may be an independent server or a server cluster formed by a plurality of servers.

The computer device 500 includes a processor 502, a memory, and a network interface 505, connected by a system bus 501, where the memory may include a non-volatile storage medium 503 and an internal memory 504.

The non-volatile storage medium 503 may store an operating system 5031 and a computer program 5032. The computer program 5032, when executed, causes the processor 502 to perform a method of accelerating NAND FLASH background inspection health checks.

The processor 502 is used to provide computing and control capabilities to support the operation of the overall computer device 500.

The internal memory 504 provides an environment for the execution of a computer program 5032 in the non-volatile storage medium 503, which computer program 5032, when executed by the processor 502, causes the processor 502 to perform a method of accelerating NAND FLASH background inspection health detection.

The network interface 505 is used for network communication with other devices. It will be appreciated by those skilled in the art that the foregoing structure is merely a block diagram of some of the structures associated with the present inventive arrangements and is not limiting of the computer device 500 to which the present inventive arrangements may be implemented, and that a particular computer device 500 may include more or less components than those shown, or may be combined with certain components, or have a different arrangement of components.

The processor 502 is configured to run a computer program 5032 stored in a memory, so as to implement a method for accelerating NAND FLASH background inspection health detection according to any one of the above embodiments, and specifically includes the following steps:

screening a target physical block to be detected from the solid state disk;

dividing WL in the target physical block into a plurality of target groups;

acquiring a test result of a medium test of WL in the target physical block;

numbering the pages in the target group;

Counting the number of error bits in the page;

In some embodiments, for example the present embodiment, the method further comprises:

and migrating the abnormal page data to a normal physical block.

It should be appreciated that in an embodiment of the invention, the Processor 502 may be a central processing unit (Central Processing Unit, CPU), the Processor 502 may also be other general purpose processors, digital signal processors (DIGITAL SIGNAL processors, DSPs), application SPECIFIC INTEGRATED Circuits (ASICs), field-Programmable gate arrays (Field-Programmable GATEARRAY, FPGA) or other Programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or the like. Wherein the general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

Those skilled in the art will appreciate that all or part of the flow in a method embodying the above described embodiments may be accomplished by computer programs instructing the relevant hardware. The computer program may be stored in a storage medium that is a computer readable storage medium. The computer program is executed by at least one processor in the computer system to implement the flow steps of the embodiments of the method described above.

Accordingly, the present invention also provides a storage medium. The storage medium may be a computer readable storage medium. The storage medium stores a computer program. The method for accelerating NAND FLASH background inspection health degree detection provided by any one of the embodiments specifically includes the following steps:

screening a target physical block to be detected from the solid state disk;

dividing WL in the target physical block into a plurality of target groups;

acquiring a test result of a medium test of WL in the target physical block;

numbering the pages in the target group;

Counting the number of error bits in the page;

And migrating the abnormal page data to a healthy physical block.

The storage medium is a physical, non-transitory storage medium, and may be, for example, a U-disk, a removable hard disk, a Read-Only Memory (ROM), a magnetic disk, or an optical disk. The computer readable storage medium may be nonvolatile or may be volatile.

Those of ordinary skill in the art will appreciate that the elements and algorithm steps described in connection with the embodiments disclosed herein may be embodied in electronic hardware, in computer software, or in a combination of the two, and that the elements and steps of the examples have been generally described in terms of function in the foregoing description to clearly illustrate the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

In the several embodiments provided by the present invention, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the device embodiments described above are merely illustrative. For example, the division of each unit is only one logic function division, and there may be another division manner in actual implementation. For example, multiple units or components may be combined or may be integrated into another system, or some features may be omitted, or not performed.

The steps in the method of the embodiment of the invention can be sequentially adjusted, combined and deleted according to actual needs. The units in the device of the embodiment of the invention can be combined, divided and deleted according to actual needs. In addition, each functional unit in the embodiments of the present invention may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit.

The integrated unit may be stored in a storage medium if implemented in the form of a software functional unit and sold or used as a stand-alone product. Based on such understanding, the technical solution of the present invention is essentially or part of what contributes to the prior art, or all or part of the technical solution may be embodied in the form of a software product stored in a storage medium, comprising several instructions for causing a computer device (which may be a personal computer, a terminal, a network device, etc.) to perform all or part of the steps of the method according to the embodiments of the present invention.

In the foregoing embodiments, the descriptions of the embodiments are focused on, and for those portions of one embodiment that are not described in detail, reference may be made to the related descriptions of other embodiments.

It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.

While the invention has been described with reference to certain preferred embodiments, it will be understood by those skilled in the art that various changes and substitutions of equivalents may be made and equivalents will be apparent to those skilled in the art without departing from the scope of the invention. Therefore, the protection scope of the invention is subject to the protection scope of the claims.

Claims

1. A method for accelerating NAND FLASH background inspection health detection, comprising:

screening a target physical block to be detected from the solid state disk;

dividing WL in the target physical block into a plurality of target groups;

2. The method for accelerating NAND FLASH background inspection health detection according to claim 1, wherein the screening the target physical block to be detected from the solid state disk includes:

3. The method of accelerating NAND FLASH background patrol health detection according to claim 1, the partitioning WLs in the target physical block into a plurality of target groups, comprising:

acquiring a test result of a medium test of WL in the target physical block;

4. The method for accelerating NAND FLASH background inspection health detection as set forth in claim 1, wherein the traversing all target groups issues a read command to one page in each target group;

numbering the pages in the target group;

5. The method for accelerating NAND FLASH background inspection health detection according to claim 1, wherein the determining whether the target group corresponding to the page has a data anomaly based on the data read from the page includes:

Counting the number of error bits in the page;

6. The method of accelerating NAND FLASH background inspection health detection as set forth in claim 5, further comprising:

7. The method for accelerating NAND FLASH background inspection health detection as set forth in claim 6, wherein the performing exception handling on the target group includes:

And migrating the abnormal page data to a healthy physical block.

8. An apparatus for accelerating NAND FLASH background inspection health detection, comprising means for performing the method of any one of claims 1-7.

9. A computer device, characterized in that it comprises a memory on which a computer program is stored and a processor which, when executing the computer program, implements the method according to any of claims 1-7.

10. A computer readable storage medium, characterized in that the storage medium stores a computer program which, when executed by a processor, implements the method according to any of claims 1-7.